/* * BSD 3-Clause License * * Copyright (c) 2005-2008, Jelmer Vernooij * Copyright (c) 2006-2018, Stefan Metzmacher * Copyright (c) 2013-2018, Andreas Schneider * Copyright (c) 2014-2017, Michael Adam * Copyright (c) 2016-2018, Anoop C S * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. Neither the name of the author nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* Socket wrapper library. Passes all socket communication over unix domain sockets if the environment variable SOCKET_WRAPPER_DIR is set. */ #include "config.h" #include #include #include #include #include #ifdef HAVE_SYS_FILIO_H #include #endif #ifdef HAVE_SYS_SIGNALFD_H #include #endif #ifdef HAVE_SYS_EVENTFD_H #include #endif #ifdef HAVE_SYS_TIMERFD_H #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef HAVE_GNU_LIB_NAMES_H #include #endif #ifdef HAVE_RPC_RPC_H #include #endif #include enum swrap_dbglvl_e { SWRAP_LOG_ERROR = 0, SWRAP_LOG_WARN, SWRAP_LOG_DEBUG, SWRAP_LOG_TRACE }; /* GCC have printf type attribute check. */ #ifdef HAVE_FUNCTION_ATTRIBUTE_FORMAT #define PRINTF_ATTRIBUTE(a,b) __attribute__ ((__format__ (__printf__, a, b))) #else #define PRINTF_ATTRIBUTE(a,b) #endif /* HAVE_FUNCTION_ATTRIBUTE_FORMAT */ #ifdef HAVE_CONSTRUCTOR_ATTRIBUTE #define CONSTRUCTOR_ATTRIBUTE __attribute__ ((constructor)) #else #define CONSTRUCTOR_ATTRIBUTE #endif /* HAVE_CONSTRUCTOR_ATTRIBUTE */ #ifdef HAVE_DESTRUCTOR_ATTRIBUTE #define DESTRUCTOR_ATTRIBUTE __attribute__ ((destructor)) #else #define DESTRUCTOR_ATTRIBUTE #endif #ifndef FALL_THROUGH # ifdef HAVE_FALLTHROUGH_ATTRIBUTE # define FALL_THROUGH __attribute__ ((fallthrough)) # else /* HAVE_FALLTHROUGH_ATTRIBUTE */ # define FALL_THROUGH ((void)0) # endif /* HAVE_FALLTHROUGH_ATTRIBUTE */ #endif /* FALL_THROUGH */ #ifdef HAVE_ADDRESS_SANITIZER_ATTRIBUTE #define DO_NOT_SANITIZE_ADDRESS_ATTRIBUTE __attribute__((no_sanitize_address)) #else #define DO_NOT_SANITIZE_ADDRESS_ATTRIBUTE #endif #ifdef HAVE_GCC_THREAD_LOCAL_STORAGE # define SWRAP_THREAD __thread #else # define SWRAP_THREAD #endif #ifndef MIN #define MIN(a,b) ((a)<(b)?(a):(b)) #endif #ifndef ZERO_STRUCT #define ZERO_STRUCT(x) memset((char *)&(x), 0, sizeof(x)) #endif #ifndef ZERO_STRUCTP #define ZERO_STRUCTP(x) do { \ if ((x) != NULL) \ memset((char *)(x), 0, sizeof(*(x))); \ } while(0) #endif #ifndef SAFE_FREE #define SAFE_FREE(x) do { if ((x) != NULL) {free(x); (x)=NULL;} } while(0) #endif #ifndef discard_const #define discard_const(ptr) ((void *)((uintptr_t)(ptr))) #endif #ifndef discard_const_p #define discard_const_p(type, ptr) ((type *)discard_const(ptr)) #endif #define UNUSED(x) (void)(x) #ifdef IPV6_PKTINFO # ifndef IPV6_RECVPKTINFO # define IPV6_RECVPKTINFO IPV6_PKTINFO # endif /* IPV6_RECVPKTINFO */ #endif /* IPV6_PKTINFO */ /* * On BSD IP_PKTINFO has a different name because during * the time when they implemented it, there was no RFC. * The name for IPv6 is the same as on Linux. */ #ifndef IP_PKTINFO # ifdef IP_RECVDSTADDR # define IP_PKTINFO IP_RECVDSTADDR # endif #endif /* Add new global locks here please */ # define SWRAP_LOCK_ALL \ swrap_mutex_lock(&libc_symbol_binding_mutex); \ # define SWRAP_UNLOCK_ALL \ swrap_mutex_unlock(&libc_symbol_binding_mutex); \ #define SOCKET_INFO_CONTAINER(si) \ (struct socket_info_container *)(si) #define SWRAP_LOCK_SI(si) do { \ struct socket_info_container *sic = SOCKET_INFO_CONTAINER(si); \ swrap_mutex_lock(&sic->meta.mutex); \ } while(0) #define SWRAP_UNLOCK_SI(si) do { \ struct socket_info_container *sic = SOCKET_INFO_CONTAINER(si); \ swrap_mutex_unlock(&sic->meta.mutex); \ } while(0) #if defined(HAVE_GETTIMEOFDAY_TZ) || defined(HAVE_GETTIMEOFDAY_TZ_VOID) #define swrapGetTimeOfDay(tval) gettimeofday(tval,NULL) #else #define swrapGetTimeOfDay(tval) gettimeofday(tval) #endif /* we need to use a very terse format here as IRIX 6.4 silently truncates names to 16 chars, so if we use a longer name then we can't tell which port a packet came from with recvfrom() with this format we have 8 chars left for the directory name */ #define SOCKET_FORMAT "%c%02X%04X" #define SOCKET_TYPE_CHAR_TCP 'T' #define SOCKET_TYPE_CHAR_UDP 'U' #define SOCKET_TYPE_CHAR_TCP_V6 'X' #define SOCKET_TYPE_CHAR_UDP_V6 'Y' /* * Set the packet MTU to 1500 bytes for stream sockets to make it it easier to * format PCAP capture files (as the caller will simply continue from here). */ #define SOCKET_WRAPPER_MTU_DEFAULT 1500 #define SOCKET_WRAPPER_MTU_MIN 512 #define SOCKET_WRAPPER_MTU_MAX 32768 #define SOCKET_MAX_SOCKETS 1024 /* * Maximum number of socket_info structures that can * be used. Can be overriden by the environment variable * SOCKET_WRAPPER_MAX_SOCKETS. */ #define SOCKET_WRAPPER_MAX_SOCKETS_DEFAULT 65535 #define SOCKET_WRAPPER_MAX_SOCKETS_LIMIT 262140 /* This limit is to avoid broadcast sendto() needing to stat too many * files. It may be raised (with a performance cost) to up to 254 * without changing the format above */ #define MAX_WRAPPED_INTERFACES 64 struct swrap_address { socklen_t sa_socklen; union { struct sockaddr s; struct sockaddr_in in; #ifdef HAVE_IPV6 struct sockaddr_in6 in6; #endif struct sockaddr_un un; struct sockaddr_storage ss; } sa; }; int first_free; struct socket_info { int family; int type; int protocol; int bound; int bcast; int is_server; int connected; int defer_connect; int pktinfo; int tcp_nodelay; /* The unix path so we can unlink it on close() */ struct sockaddr_un un_addr; struct swrap_address bindname; struct swrap_address myname; struct swrap_address peername; struct { unsigned long pck_snd; unsigned long pck_rcv; } io; }; struct socket_info_meta { unsigned int refcount; int next_free; pthread_mutex_t mutex; }; struct socket_info_container { struct socket_info info; struct socket_info_meta meta; }; static struct socket_info_container *sockets; static size_t socket_info_max = 0; /* * Allocate the socket array always on the limit value. We want it to be * at least bigger than the default so if we reach the limit we can * still deal with duplicate fds pointing to the same socket_info. */ static size_t socket_fds_max = SOCKET_WRAPPER_MAX_SOCKETS_LIMIT; /* Hash table to map fds to corresponding socket_info index */ static int *socket_fds_idx; /* Mutex to synchronize access to global libc.symbols */ static pthread_mutex_t libc_symbol_binding_mutex = PTHREAD_MUTEX_INITIALIZER; /* Mutex for syncronizing port selection during swrap_auto_bind() */ static pthread_mutex_t autobind_start_mutex; /* Mutex to guard the initialization of array of socket_info structures */ static pthread_mutex_t sockets_mutex; /* Mutex to guard the socket reset in swrap_close() and swrap_remove_stale() */ static pthread_mutex_t socket_reset_mutex; /* Mutex to synchronize access to first free index in socket_info array */ static pthread_mutex_t first_free_mutex; /* Mutex to synchronize access to packet capture dump file */ static pthread_mutex_t pcap_dump_mutex; /* Mutex for synchronizing mtu value fetch*/ static pthread_mutex_t mtu_update_mutex; /* Function prototypes */ bool socket_wrapper_enabled(void); void swrap_constructor(void) CONSTRUCTOR_ATTRIBUTE; void swrap_destructor(void) DESTRUCTOR_ATTRIBUTE; #ifndef HAVE_GETPROGNAME static const char *getprogname(void) { #if defined(HAVE_PROGRAM_INVOCATION_SHORT_NAME) return program_invocation_short_name; #elif defined(HAVE_GETEXECNAME) return getexecname(); #else return NULL; #endif /* HAVE_PROGRAM_INVOCATION_SHORT_NAME */ } #endif /* HAVE_GETPROGNAME */ static void swrap_log(enum swrap_dbglvl_e dbglvl, const char *func, const char *format, ...) PRINTF_ATTRIBUTE(3, 4); # define SWRAP_LOG(dbglvl, ...) swrap_log((dbglvl), __func__, __VA_ARGS__) static void swrap_log(enum swrap_dbglvl_e dbglvl, const char *func, const char *format, ...) { char buffer[1024]; va_list va; const char *d; unsigned int lvl = 0; const char *prefix = "SWRAP"; const char *progname = getprogname(); d = getenv("SOCKET_WRAPPER_DEBUGLEVEL"); if (d != NULL) { lvl = atoi(d); } if (lvl < dbglvl) { return; } va_start(va, format); vsnprintf(buffer, sizeof(buffer), format, va); va_end(va); switch (dbglvl) { case SWRAP_LOG_ERROR: prefix = "SWRAP_ERROR"; break; case SWRAP_LOG_WARN: prefix = "SWRAP_WARN"; break; case SWRAP_LOG_DEBUG: prefix = "SWRAP_DEBUG"; break; case SWRAP_LOG_TRACE: prefix = "SWRAP_TRACE"; break; } if (progname == NULL) { progname = ""; } fprintf(stderr, "%s[%s (%u)] - %s: %s\n", prefix, progname, (unsigned int)getpid(), func, buffer); } /********************************************************* * SWRAP LOADING LIBC FUNCTIONS *********************************************************/ #include #ifdef HAVE_ACCEPT4 typedef int (*__libc_accept4)(int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags); #else typedef int (*__libc_accept)(int sockfd, struct sockaddr *addr, socklen_t *addrlen); #endif typedef int (*__libc_bind)(int sockfd, const struct sockaddr *addr, socklen_t addrlen); typedef int (*__libc_close)(int fd); typedef int (*__libc_connect)(int sockfd, const struct sockaddr *addr, socklen_t addrlen); typedef int (*__libc_dup)(int fd); typedef int (*__libc_dup2)(int oldfd, int newfd); typedef int (*__libc_fcntl)(int fd, int cmd, ...); typedef FILE *(*__libc_fopen)(const char *name, const char *mode); #ifdef HAVE_FOPEN64 typedef FILE *(*__libc_fopen64)(const char *name, const char *mode); #endif #ifdef HAVE_EVENTFD typedef int (*__libc_eventfd)(int count, int flags); #endif typedef int (*__libc_getpeername)(int sockfd, struct sockaddr *addr, socklen_t *addrlen); typedef int (*__libc_getsockname)(int sockfd, struct sockaddr *addr, socklen_t *addrlen); typedef int (*__libc_getsockopt)(int sockfd, int level, int optname, void *optval, socklen_t *optlen); typedef int (*__libc_ioctl)(int d, unsigned long int request, ...); typedef int (*__libc_listen)(int sockfd, int backlog); typedef int (*__libc_open)(const char *pathname, int flags, ...); #ifdef HAVE_OPEN64 typedef int (*__libc_open64)(const char *pathname, int flags, ...); #endif /* HAVE_OPEN64 */ typedef int (*__libc_openat)(int dirfd, const char *path, int flags, ...); typedef int (*__libc_pipe)(int pipefd[2]); typedef int (*__libc_read)(int fd, void *buf, size_t count); typedef ssize_t (*__libc_readv)(int fd, const struct iovec *iov, int iovcnt); typedef int (*__libc_recv)(int sockfd, void *buf, size_t len, int flags); typedef int (*__libc_recvfrom)(int sockfd, void *buf, size_t len, int flags, struct sockaddr *src_addr, socklen_t *addrlen); typedef int (*__libc_recvmsg)(int sockfd, const struct msghdr *msg, int flags); typedef int (*__libc_send)(int sockfd, const void *buf, size_t len, int flags); typedef int (*__libc_sendmsg)(int sockfd, const struct msghdr *msg, int flags); typedef int (*__libc_sendto)(int sockfd, const void *buf, size_t len, int flags, const struct sockaddr *dst_addr, socklen_t addrlen); typedef int (*__libc_setsockopt)(int sockfd, int level, int optname, const void *optval, socklen_t optlen); #ifdef HAVE_SIGNALFD typedef int (*__libc_signalfd)(int fd, const sigset_t *mask, int flags); #endif typedef int (*__libc_socket)(int domain, int type, int protocol); typedef int (*__libc_socketpair)(int domain, int type, int protocol, int sv[2]); #ifdef HAVE_TIMERFD_CREATE typedef int (*__libc_timerfd_create)(int clockid, int flags); #endif typedef ssize_t (*__libc_write)(int fd, const void *buf, size_t count); typedef ssize_t (*__libc_writev)(int fd, const struct iovec *iov, int iovcnt); #define SWRAP_SYMBOL_ENTRY(i) \ union { \ __libc_##i f; \ void *obj; \ } _libc_##i struct swrap_libc_symbols { #ifdef HAVE_ACCEPT4 SWRAP_SYMBOL_ENTRY(accept4); #else SWRAP_SYMBOL_ENTRY(accept); #endif SWRAP_SYMBOL_ENTRY(bind); SWRAP_SYMBOL_ENTRY(close); SWRAP_SYMBOL_ENTRY(connect); SWRAP_SYMBOL_ENTRY(dup); SWRAP_SYMBOL_ENTRY(dup2); SWRAP_SYMBOL_ENTRY(fcntl); SWRAP_SYMBOL_ENTRY(fopen); #ifdef HAVE_FOPEN64 SWRAP_SYMBOL_ENTRY(fopen64); #endif #ifdef HAVE_EVENTFD SWRAP_SYMBOL_ENTRY(eventfd); #endif SWRAP_SYMBOL_ENTRY(getpeername); SWRAP_SYMBOL_ENTRY(getsockname); SWRAP_SYMBOL_ENTRY(getsockopt); SWRAP_SYMBOL_ENTRY(ioctl); SWRAP_SYMBOL_ENTRY(listen); SWRAP_SYMBOL_ENTRY(open); #ifdef HAVE_OPEN64 SWRAP_SYMBOL_ENTRY(open64); #endif SWRAP_SYMBOL_ENTRY(openat); SWRAP_SYMBOL_ENTRY(pipe); SWRAP_SYMBOL_ENTRY(read); SWRAP_SYMBOL_ENTRY(readv); SWRAP_SYMBOL_ENTRY(recv); SWRAP_SYMBOL_ENTRY(recvfrom); SWRAP_SYMBOL_ENTRY(recvmsg); SWRAP_SYMBOL_ENTRY(send); SWRAP_SYMBOL_ENTRY(sendmsg); SWRAP_SYMBOL_ENTRY(sendto); SWRAP_SYMBOL_ENTRY(setsockopt); #ifdef HAVE_SIGNALFD SWRAP_SYMBOL_ENTRY(signalfd); #endif SWRAP_SYMBOL_ENTRY(socket); SWRAP_SYMBOL_ENTRY(socketpair); #ifdef HAVE_TIMERFD_CREATE SWRAP_SYMBOL_ENTRY(timerfd_create); #endif SWRAP_SYMBOL_ENTRY(write); SWRAP_SYMBOL_ENTRY(writev); }; struct swrap { struct { void *handle; void *socket_handle; struct swrap_libc_symbols symbols; } libc; }; static struct swrap swrap; /* prototypes */ static char *socket_wrapper_dir(void); #define LIBC_NAME "libc.so" enum swrap_lib { SWRAP_LIBC, SWRAP_LIBNSL, SWRAP_LIBSOCKET, }; static const char *swrap_str_lib(enum swrap_lib lib) { switch (lib) { case SWRAP_LIBC: return "libc"; case SWRAP_LIBNSL: return "libnsl"; case SWRAP_LIBSOCKET: return "libsocket"; } /* Compiler would warn us about unhandled enum value if we get here */ return "unknown"; } static void *swrap_load_lib_handle(enum swrap_lib lib) { int flags = RTLD_LAZY; void *handle = NULL; int i; #ifdef RTLD_DEEPBIND const char *env_preload = getenv("LD_PRELOAD"); const char *env_deepbind = getenv("SOCKET_WRAPPER_DISABLE_DEEPBIND"); bool enable_deepbind = true; /* Don't do a deepbind if we run with libasan */ if (env_preload != NULL && strlen(env_preload) < 1024) { const char *p = strstr(env_preload, "libasan.so"); if (p != NULL) { enable_deepbind = false; } } if (env_deepbind != NULL && strlen(env_deepbind) >= 1) { enable_deepbind = false; } if (enable_deepbind) { flags |= RTLD_DEEPBIND; } #endif switch (lib) { case SWRAP_LIBNSL: case SWRAP_LIBSOCKET: #ifdef HAVE_LIBSOCKET handle = swrap.libc.socket_handle; if (handle == NULL) { for (i = 10; i >= 0; i--) { char soname[256] = {0}; snprintf(soname, sizeof(soname), "libsocket.so.%d", i); handle = dlopen(soname, flags); if (handle != NULL) { break; } } swrap.libc.socket_handle = handle; } break; #endif case SWRAP_LIBC: handle = swrap.libc.handle; #ifdef LIBC_SO if (handle == NULL) { handle = dlopen(LIBC_SO, flags); swrap.libc.handle = handle; } #endif if (handle == NULL) { for (i = 10; i >= 0; i--) { char soname[256] = {0}; snprintf(soname, sizeof(soname), "libc.so.%d", i); handle = dlopen(soname, flags); if (handle != NULL) { break; } } swrap.libc.handle = handle; } break; } if (handle == NULL) { #ifdef RTLD_NEXT handle = swrap.libc.handle = swrap.libc.socket_handle = RTLD_NEXT; #else SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to dlopen library: %s\n", dlerror()); exit(-1); #endif } return handle; } static void *_swrap_bind_symbol(enum swrap_lib lib, const char *fn_name) { void *handle; void *func; handle = swrap_load_lib_handle(lib); func = dlsym(handle, fn_name); if (func == NULL) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to find %s: %s\n", fn_name, dlerror()); exit(-1); } SWRAP_LOG(SWRAP_LOG_TRACE, "Loaded %s from %s", fn_name, swrap_str_lib(lib)); return func; } static void swrap_mutex_lock(pthread_mutex_t *mutex) { int ret; ret = pthread_mutex_lock(mutex); if (ret != 0) { SWRAP_LOG(SWRAP_LOG_ERROR, "Couldn't lock pthread mutex - %s", strerror(ret)); } } static void swrap_mutex_unlock(pthread_mutex_t *mutex) { int ret; ret = pthread_mutex_unlock(mutex); if (ret != 0) { SWRAP_LOG(SWRAP_LOG_ERROR, "Couldn't unlock pthread mutex - %s", strerror(ret)); } } /* * These macros have a thread race condition on purpose! * * This is an optimization to avoid locking each time we check if the symbol is * bound. */ #define swrap_bind_symbol_libc(sym_name) \ if (swrap.libc.symbols._libc_##sym_name.obj == NULL) { \ swrap_mutex_lock(&libc_symbol_binding_mutex); \ if (swrap.libc.symbols._libc_##sym_name.obj == NULL) { \ swrap.libc.symbols._libc_##sym_name.obj = \ _swrap_bind_symbol(SWRAP_LIBC, #sym_name); \ } \ swrap_mutex_unlock(&libc_symbol_binding_mutex); \ } #define swrap_bind_symbol_libsocket(sym_name) \ if (swrap.libc.symbols._libc_##sym_name.obj == NULL) { \ swrap_mutex_lock(&libc_symbol_binding_mutex); \ if (swrap.libc.symbols._libc_##sym_name.obj == NULL) { \ swrap.libc.symbols._libc_##sym_name.obj = \ _swrap_bind_symbol(SWRAP_LIBSOCKET, #sym_name); \ } \ swrap_mutex_unlock(&libc_symbol_binding_mutex); \ } #define swrap_bind_symbol_libnsl(sym_name) \ if (swrap.libc.symbols._libc_##sym_name.obj == NULL) { \ swrap_mutex_lock(&libc_symbol_binding_mutex); \ if (swrap.libc.symbols._libc_##sym_name.obj == NULL) { \ swrap.libc.symbols._libc_##sym_name.obj = \ _swrap_bind_symbol(SWRAP_LIBNSL, #sym_name); \ } \ swrap_mutex_unlock(&libc_symbol_binding_mutex); \ } /**************************************************************************** * IMPORTANT **************************************************************************** * * Functions especially from libc need to be loaded individually, you can't * load all at once or gdb will segfault at startup. The same applies to * valgrind and has probably something todo with with the linker. So we need * load each function at the point it is called the first time. * ****************************************************************************/ #ifdef HAVE_ACCEPT4 static int libc_accept4(int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags) { swrap_bind_symbol_libsocket(accept4); return swrap.libc.symbols._libc_accept4.f(sockfd, addr, addrlen, flags); } #else /* HAVE_ACCEPT4 */ static int libc_accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen) { swrap_bind_symbol_libsocket(accept); return swrap.libc.symbols._libc_accept.f(sockfd, addr, addrlen); } #endif /* HAVE_ACCEPT4 */ static int libc_bind(int sockfd, const struct sockaddr *addr, socklen_t addrlen) { swrap_bind_symbol_libsocket(bind); return swrap.libc.symbols._libc_bind.f(sockfd, addr, addrlen); } static int libc_close(int fd) { swrap_bind_symbol_libc(close); return swrap.libc.symbols._libc_close.f(fd); } static int libc_connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen) { swrap_bind_symbol_libsocket(connect); return swrap.libc.symbols._libc_connect.f(sockfd, addr, addrlen); } static int libc_dup(int fd) { swrap_bind_symbol_libc(dup); return swrap.libc.symbols._libc_dup.f(fd); } static int libc_dup2(int oldfd, int newfd) { swrap_bind_symbol_libc(dup2); return swrap.libc.symbols._libc_dup2.f(oldfd, newfd); } #ifdef HAVE_EVENTFD static int libc_eventfd(int count, int flags) { swrap_bind_symbol_libc(eventfd); return swrap.libc.symbols._libc_eventfd.f(count, flags); } #endif DO_NOT_SANITIZE_ADDRESS_ATTRIBUTE static int libc_vfcntl(int fd, int cmd, va_list ap) { void *arg; int rc; swrap_bind_symbol_libc(fcntl); arg = va_arg(ap, void *); rc = swrap.libc.symbols._libc_fcntl.f(fd, cmd, arg); return rc; } static int libc_getpeername(int sockfd, struct sockaddr *addr, socklen_t *addrlen) { swrap_bind_symbol_libsocket(getpeername); return swrap.libc.symbols._libc_getpeername.f(sockfd, addr, addrlen); } static int libc_getsockname(int sockfd, struct sockaddr *addr, socklen_t *addrlen) { swrap_bind_symbol_libsocket(getsockname); return swrap.libc.symbols._libc_getsockname.f(sockfd, addr, addrlen); } static int libc_getsockopt(int sockfd, int level, int optname, void *optval, socklen_t *optlen) { swrap_bind_symbol_libsocket(getsockopt); return swrap.libc.symbols._libc_getsockopt.f(sockfd, level, optname, optval, optlen); } DO_NOT_SANITIZE_ADDRESS_ATTRIBUTE static int libc_vioctl(int d, unsigned long int request, va_list ap) { void *arg; int rc; swrap_bind_symbol_libc(ioctl); arg = va_arg(ap, void *); rc = swrap.libc.symbols._libc_ioctl.f(d, request, arg); return rc; } static int libc_listen(int sockfd, int backlog) { swrap_bind_symbol_libsocket(listen); return swrap.libc.symbols._libc_listen.f(sockfd, backlog); } static FILE *libc_fopen(const char *name, const char *mode) { swrap_bind_symbol_libc(fopen); return swrap.libc.symbols._libc_fopen.f(name, mode); } #ifdef HAVE_FOPEN64 static FILE *libc_fopen64(const char *name, const char *mode) { swrap_bind_symbol_libc(fopen64); return swrap.libc.symbols._libc_fopen64.f(name, mode); } #endif /* HAVE_FOPEN64 */ static int libc_vopen(const char *pathname, int flags, va_list ap) { int mode = 0; int fd; swrap_bind_symbol_libc(open); if (flags & O_CREAT) { mode = va_arg(ap, int); } fd = swrap.libc.symbols._libc_open.f(pathname, flags, (mode_t)mode); return fd; } static int libc_open(const char *pathname, int flags, ...) { va_list ap; int fd; va_start(ap, flags); fd = libc_vopen(pathname, flags, ap); va_end(ap); return fd; } #ifdef HAVE_OPEN64 static int libc_vopen64(const char *pathname, int flags, va_list ap) { int mode = 0; int fd; swrap_bind_symbol_libc(open64); if (flags & O_CREAT) { mode = va_arg(ap, int); } fd = swrap.libc.symbols._libc_open64.f(pathname, flags, (mode_t)mode); return fd; } #endif /* HAVE_OPEN64 */ static int libc_vopenat(int dirfd, const char *path, int flags, va_list ap) { int mode = 0; int fd; swrap_bind_symbol_libc(openat); if (flags & O_CREAT) { mode = va_arg(ap, int); } fd = swrap.libc.symbols._libc_openat.f(dirfd, path, flags, (mode_t)mode); return fd; } #if 0 static int libc_openat(int dirfd, const char *path, int flags, ...) { va_list ap; int fd; va_start(ap, flags); fd = libc_vopenat(dirfd, path, flags, ap); va_end(ap); return fd; } #endif static int libc_pipe(int pipefd[2]) { swrap_bind_symbol_libsocket(pipe); return swrap.libc.symbols._libc_pipe.f(pipefd); } static int libc_read(int fd, void *buf, size_t count) { swrap_bind_symbol_libc(read); return swrap.libc.symbols._libc_read.f(fd, buf, count); } static ssize_t libc_readv(int fd, const struct iovec *iov, int iovcnt) { swrap_bind_symbol_libsocket(readv); return swrap.libc.symbols._libc_readv.f(fd, iov, iovcnt); } static int libc_recv(int sockfd, void *buf, size_t len, int flags) { swrap_bind_symbol_libsocket(recv); return swrap.libc.symbols._libc_recv.f(sockfd, buf, len, flags); } static int libc_recvfrom(int sockfd, void *buf, size_t len, int flags, struct sockaddr *src_addr, socklen_t *addrlen) { swrap_bind_symbol_libsocket(recvfrom); return swrap.libc.symbols._libc_recvfrom.f(sockfd, buf, len, flags, src_addr, addrlen); } static int libc_recvmsg(int sockfd, struct msghdr *msg, int flags) { swrap_bind_symbol_libsocket(recvmsg); return swrap.libc.symbols._libc_recvmsg.f(sockfd, msg, flags); } static int libc_send(int sockfd, const void *buf, size_t len, int flags) { swrap_bind_symbol_libsocket(send); return swrap.libc.symbols._libc_send.f(sockfd, buf, len, flags); } static int libc_sendmsg(int sockfd, const struct msghdr *msg, int flags) { swrap_bind_symbol_libsocket(sendmsg); return swrap.libc.symbols._libc_sendmsg.f(sockfd, msg, flags); } static int libc_sendto(int sockfd, const void *buf, size_t len, int flags, const struct sockaddr *dst_addr, socklen_t addrlen) { swrap_bind_symbol_libsocket(sendto); return swrap.libc.symbols._libc_sendto.f(sockfd, buf, len, flags, dst_addr, addrlen); } static int libc_setsockopt(int sockfd, int level, int optname, const void *optval, socklen_t optlen) { swrap_bind_symbol_libsocket(setsockopt); return swrap.libc.symbols._libc_setsockopt.f(sockfd, level, optname, optval, optlen); } #ifdef HAVE_SIGNALFD static int libc_signalfd(int fd, const sigset_t *mask, int flags) { swrap_bind_symbol_libsocket(signalfd); return swrap.libc.symbols._libc_signalfd.f(fd, mask, flags); } #endif static int libc_socket(int domain, int type, int protocol) { swrap_bind_symbol_libsocket(socket); return swrap.libc.symbols._libc_socket.f(domain, type, protocol); } static int libc_socketpair(int domain, int type, int protocol, int sv[2]) { swrap_bind_symbol_libsocket(socketpair); return swrap.libc.symbols._libc_socketpair.f(domain, type, protocol, sv); } #ifdef HAVE_TIMERFD_CREATE static int libc_timerfd_create(int clockid, int flags) { swrap_bind_symbol_libc(timerfd_create); return swrap.libc.symbols._libc_timerfd_create.f(clockid, flags); } #endif static ssize_t libc_write(int fd, const void *buf, size_t count) { swrap_bind_symbol_libc(write); return swrap.libc.symbols._libc_write.f(fd, buf, count); } static ssize_t libc_writev(int fd, const struct iovec *iov, int iovcnt) { swrap_bind_symbol_libsocket(writev); return swrap.libc.symbols._libc_writev.f(fd, iov, iovcnt); } /* DO NOT call this function during library initialization! */ static void swrap_bind_symbol_all(void) { #ifdef HAVE_ACCEPT4 swrap_bind_symbol_libsocket(accept4); #else swrap_bind_symbol_libsocket(accept); #endif swrap_bind_symbol_libsocket(bind); swrap_bind_symbol_libc(close); swrap_bind_symbol_libsocket(connect); swrap_bind_symbol_libc(dup); swrap_bind_symbol_libc(dup2); swrap_bind_symbol_libc(fcntl); swrap_bind_symbol_libc(fopen); #ifdef HAVE_FOPEN64 swrap_bind_symbol_libc(fopen64); #endif #ifdef HAVE_EVENTFD swrap_bind_symbol_libc(eventfd); #endif swrap_bind_symbol_libsocket(getpeername); swrap_bind_symbol_libsocket(getsockname); swrap_bind_symbol_libsocket(getsockopt); swrap_bind_symbol_libc(ioctl); swrap_bind_symbol_libsocket(listen); swrap_bind_symbol_libc(open); #ifdef HAVE_OPEN64 swrap_bind_symbol_libc(open64); #endif swrap_bind_symbol_libc(openat); swrap_bind_symbol_libsocket(pipe); swrap_bind_symbol_libc(read); swrap_bind_symbol_libsocket(readv); swrap_bind_symbol_libsocket(recv); swrap_bind_symbol_libsocket(recvfrom); swrap_bind_symbol_libsocket(recvmsg); swrap_bind_symbol_libsocket(send); swrap_bind_symbol_libsocket(sendmsg); swrap_bind_symbol_libsocket(sendto); swrap_bind_symbol_libsocket(setsockopt); #ifdef HAVE_SIGNALFD swrap_bind_symbol_libsocket(signalfd); #endif swrap_bind_symbol_libsocket(socket); swrap_bind_symbol_libsocket(socketpair); #ifdef HAVE_TIMERFD_CREATE swrap_bind_symbol_libc(timerfd_create); #endif swrap_bind_symbol_libc(write); swrap_bind_symbol_libsocket(writev); } /********************************************************* * SWRAP HELPER FUNCTIONS *********************************************************/ #ifdef HAVE_IPV6 /* * FD00::5357:5FXX */ static const struct in6_addr *swrap_ipv6(void) { static struct in6_addr v; static int initialized; int ret; if (initialized) { return &v; } initialized = 1; ret = inet_pton(AF_INET6, "FD00::5357:5F00", &v); if (ret <= 0) { abort(); } return &v; } #endif static void set_port(int family, int prt, struct swrap_address *addr) { switch (family) { case AF_INET: addr->sa.in.sin_port = htons(prt); break; #ifdef HAVE_IPV6 case AF_INET6: addr->sa.in6.sin6_port = htons(prt); break; #endif } } static size_t socket_length(int family) { switch (family) { case AF_INET: return sizeof(struct sockaddr_in); #ifdef HAVE_IPV6 case AF_INET6: return sizeof(struct sockaddr_in6); #endif } return 0; } static struct socket_info *swrap_get_socket_info(int si_index) { return (struct socket_info *)(&(sockets[si_index].info)); } static int swrap_get_refcount(struct socket_info *si) { struct socket_info_container *sic = SOCKET_INFO_CONTAINER(si); return sic->meta.refcount; } static void swrap_inc_refcount(struct socket_info *si) { struct socket_info_container *sic = SOCKET_INFO_CONTAINER(si); sic->meta.refcount += 1; } static void swrap_dec_refcount(struct socket_info *si) { struct socket_info_container *sic = SOCKET_INFO_CONTAINER(si); sic->meta.refcount -= 1; } static int swrap_get_next_free(struct socket_info *si) { struct socket_info_container *sic = SOCKET_INFO_CONTAINER(si); return sic->meta.next_free; } static void swrap_set_next_free(struct socket_info *si, int next_free) { struct socket_info_container *sic = SOCKET_INFO_CONTAINER(si); sic->meta.next_free = next_free; } static char *socket_wrapper_dir(void) { char *swrap_dir = NULL; char *s = getenv("SOCKET_WRAPPER_DIR"); if (s == NULL) { SWRAP_LOG(SWRAP_LOG_WARN, "SOCKET_WRAPPER_DIR not set\n"); return NULL; } swrap_dir = realpath(s, NULL); if (swrap_dir == NULL) { SWRAP_LOG(SWRAP_LOG_ERROR, "Unable to resolve socket_wrapper dir path: %s", strerror(errno)); return NULL; } SWRAP_LOG(SWRAP_LOG_TRACE, "socket_wrapper_dir: %s", swrap_dir); return swrap_dir; } static unsigned int socket_wrapper_mtu(void) { static unsigned int max_mtu = 0; unsigned int tmp; const char *s; char *endp; swrap_mutex_lock(&mtu_update_mutex); if (max_mtu != 0) { goto done; } max_mtu = SOCKET_WRAPPER_MTU_DEFAULT; s = getenv("SOCKET_WRAPPER_MTU"); if (s == NULL) { goto done; } tmp = strtol(s, &endp, 10); if (s == endp) { goto done; } if (tmp < SOCKET_WRAPPER_MTU_MIN || tmp > SOCKET_WRAPPER_MTU_MAX) { goto done; } max_mtu = tmp; done: swrap_mutex_unlock(&mtu_update_mutex); return max_mtu; } static int socket_wrapper_init_mutex(pthread_mutex_t *m) { pthread_mutexattr_t ma; int ret; ret = pthread_mutexattr_init(&ma); if (ret != 0) { return ret; } ret = pthread_mutexattr_settype(&ma, PTHREAD_MUTEX_ERRORCHECK); if (ret != 0) { goto done; } ret = pthread_mutex_init(m, &ma); done: pthread_mutexattr_destroy(&ma); return ret; } static size_t socket_wrapper_max_sockets(void) { const char *s; size_t tmp; char *endp; if (socket_info_max != 0) { return socket_info_max; } socket_info_max = SOCKET_WRAPPER_MAX_SOCKETS_DEFAULT; s = getenv("SOCKET_WRAPPER_MAX_SOCKETS"); if (s == NULL || s[0] == '\0') { goto done; } tmp = strtoul(s, &endp, 10); if (s == endp) { goto done; } if (tmp == 0) { tmp = SOCKET_WRAPPER_MAX_SOCKETS_DEFAULT; SWRAP_LOG(SWRAP_LOG_ERROR, "Invalid number of sockets specified, " "using default (%zu)", tmp); } if (tmp > SOCKET_WRAPPER_MAX_SOCKETS_LIMIT) { tmp = SOCKET_WRAPPER_MAX_SOCKETS_LIMIT; SWRAP_LOG(SWRAP_LOG_ERROR, "Invalid number of sockets specified, " "using maximum (%zu).", tmp); } socket_info_max = tmp; done: return socket_info_max; } static void socket_wrapper_init_fds_idx(void) { int *tmp = NULL; size_t i; if (socket_fds_idx != NULL) { return; } tmp = (int *)calloc(socket_fds_max, sizeof(int)); if (tmp == NULL) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to allocate socket fds index array: %s", strerror(errno)); exit(-1); } for (i = 0; i < socket_fds_max; i++) { tmp[i] = -1; } socket_fds_idx = tmp; } static void socket_wrapper_init_sockets(void) { size_t max_sockets; size_t i; int ret; swrap_mutex_lock(&sockets_mutex); if (sockets != NULL) { swrap_mutex_unlock(&sockets_mutex); return; } socket_wrapper_init_fds_idx(); /* Needs to be called inside the sockets_mutex lock here. */ max_sockets = socket_wrapper_max_sockets(); sockets = (struct socket_info_container *)calloc(max_sockets, sizeof(struct socket_info_container)); if (sockets == NULL) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to allocate sockets array: %s", strerror(errno)); swrap_mutex_unlock(&sockets_mutex); exit(-1); } swrap_mutex_lock(&first_free_mutex); first_free = 0; for (i = 0; i < max_sockets; i++) { swrap_set_next_free(&sockets[i].info, i+1); ret = socket_wrapper_init_mutex(&sockets[i].meta.mutex); if (ret != 0) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to initialize pthread mutex"); goto done; } } /* mark the end of the free list */ swrap_set_next_free(&sockets[max_sockets-1].info, -1); ret = socket_wrapper_init_mutex(&autobind_start_mutex); if (ret != 0) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to initialize pthread mutex"); goto done; } ret = socket_wrapper_init_mutex(&pcap_dump_mutex); if (ret != 0) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to initialize pthread mutex"); goto done; } ret = socket_wrapper_init_mutex(&mtu_update_mutex); if (ret != 0) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to initialize pthread mutex"); goto done; } done: swrap_mutex_unlock(&first_free_mutex); swrap_mutex_unlock(&sockets_mutex); if (ret != 0) { exit(-1); } } bool socket_wrapper_enabled(void) { char *s = socket_wrapper_dir(); if (s == NULL) { return false; } SAFE_FREE(s); socket_wrapper_init_sockets(); return true; } static unsigned int socket_wrapper_default_iface(void) { const char *s = getenv("SOCKET_WRAPPER_DEFAULT_IFACE"); if (s) { unsigned int iface; if (sscanf(s, "%u", &iface) == 1) { if (iface >= 1 && iface <= MAX_WRAPPED_INTERFACES) { return iface; } } } return 1;/* 127.0.0.1 */ } static void set_socket_info_index(int fd, int idx) { socket_fds_idx[fd] = idx; /* This builtin issues a full memory barrier. */ __sync_synchronize(); } static void reset_socket_info_index(int fd) { set_socket_info_index(fd, -1); } static int find_socket_info_index(int fd) { if (fd < 0) { return -1; } if (socket_fds_idx == NULL) { return -1; } if ((size_t)fd >= socket_fds_max) { /* * Do not add a log here as some applications do stupid things * like: * * for (fd = 0; fd <= getdtablesize(); fd++) { * close(fd) * }; * * This would produce millions of lines of debug messages. */ #if 0 SWRAP_LOG(SWRAP_LOG_ERROR, "Looking for a socket info for the fd %d is over the " "max socket index limit of %zu.", fd, socket_fds_max); #endif return -1; } /* This builtin issues a full memory barrier. */ __sync_synchronize(); return socket_fds_idx[fd]; } static int swrap_add_socket_info(struct socket_info *si_input) { struct socket_info *si = NULL; int si_index = -1; if (si_input == NULL) { errno = EINVAL; return -1; } swrap_mutex_lock(&first_free_mutex); if (first_free == -1) { errno = ENFILE; goto out; } si_index = first_free; si = swrap_get_socket_info(si_index); SWRAP_LOCK_SI(si); first_free = swrap_get_next_free(si); *si = *si_input; swrap_inc_refcount(si); SWRAP_UNLOCK_SI(si); out: swrap_mutex_unlock(&first_free_mutex); return si_index; } static int swrap_create_socket(struct socket_info *si, int fd) { int idx; if ((size_t)fd >= socket_fds_max) { SWRAP_LOG(SWRAP_LOG_ERROR, "The max socket index limit of %zu has been reached, " "trying to add %d", socket_fds_max, fd); return -1; } idx = swrap_add_socket_info(si); if (idx == -1) { return -1; } set_socket_info_index(fd, idx); return idx; } static int convert_un_in(const struct sockaddr_un *un, struct sockaddr *in, socklen_t *len) { unsigned int iface; unsigned int prt; const char *p; char type; p = strrchr(un->sun_path, '/'); if (p) p++; else p = un->sun_path; if (sscanf(p, SOCKET_FORMAT, &type, &iface, &prt) != 3) { errno = EINVAL; return -1; } SWRAP_LOG(SWRAP_LOG_TRACE, "type %c iface %u port %u", type, iface, prt); if (iface == 0 || iface > MAX_WRAPPED_INTERFACES) { errno = EINVAL; return -1; } if (prt > 0xFFFF) { errno = EINVAL; return -1; } switch(type) { case SOCKET_TYPE_CHAR_TCP: case SOCKET_TYPE_CHAR_UDP: { struct sockaddr_in *in2 = (struct sockaddr_in *)(void *)in; if ((*len) < sizeof(*in2)) { errno = EINVAL; return -1; } memset(in2, 0, sizeof(*in2)); in2->sin_family = AF_INET; in2->sin_addr.s_addr = htonl((127<<24) | iface); in2->sin_port = htons(prt); *len = sizeof(*in2); break; } #ifdef HAVE_IPV6 case SOCKET_TYPE_CHAR_TCP_V6: case SOCKET_TYPE_CHAR_UDP_V6: { struct sockaddr_in6 *in2 = (struct sockaddr_in6 *)(void *)in; if ((*len) < sizeof(*in2)) { errno = EINVAL; return -1; } memset(in2, 0, sizeof(*in2)); in2->sin6_family = AF_INET6; in2->sin6_addr = *swrap_ipv6(); in2->sin6_addr.s6_addr[15] = iface; in2->sin6_port = htons(prt); *len = sizeof(*in2); break; } #endif default: errno = EINVAL; return -1; } return 0; } static int convert_in_un_remote(struct socket_info *si, const struct sockaddr *inaddr, struct sockaddr_un *un, int *bcast) { char type = '\0'; unsigned int prt; unsigned int iface; int is_bcast = 0; char *swrap_dir = NULL; if (bcast) *bcast = 0; switch (inaddr->sa_family) { case AF_INET: { const struct sockaddr_in *in = (const struct sockaddr_in *)(const void *)inaddr; unsigned int addr = ntohl(in->sin_addr.s_addr); char u_type = '\0'; char b_type = '\0'; char a_type = '\0'; switch (si->type) { case SOCK_STREAM: u_type = SOCKET_TYPE_CHAR_TCP; break; case SOCK_DGRAM: u_type = SOCKET_TYPE_CHAR_UDP; a_type = SOCKET_TYPE_CHAR_UDP; b_type = SOCKET_TYPE_CHAR_UDP; break; default: SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown socket type!\n"); errno = ESOCKTNOSUPPORT; return -1; } prt = ntohs(in->sin_port); if (a_type && addr == 0xFFFFFFFF) { /* 255.255.255.255 only udp */ is_bcast = 2; type = a_type; iface = socket_wrapper_default_iface(); } else if (b_type && addr == 0x7FFFFFFF) { /* 127.255.255.255 only udp */ is_bcast = 1; type = b_type; iface = socket_wrapper_default_iface(); } else if ((addr & 0xFFFFFF00) == 0x7F000000) { /* 127.0.0.X */ is_bcast = 0; type = u_type; iface = (addr & 0x000000FF); } else { errno = ENETUNREACH; return -1; } if (bcast) *bcast = is_bcast; break; } #ifdef HAVE_IPV6 case AF_INET6: { const struct sockaddr_in6 *in = (const struct sockaddr_in6 *)(const void *)inaddr; struct in6_addr cmp1, cmp2; switch (si->type) { case SOCK_STREAM: type = SOCKET_TYPE_CHAR_TCP_V6; break; case SOCK_DGRAM: type = SOCKET_TYPE_CHAR_UDP_V6; break; default: SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown socket type!\n"); errno = ESOCKTNOSUPPORT; return -1; } /* XXX no multicast/broadcast */ prt = ntohs(in->sin6_port); cmp1 = *swrap_ipv6(); cmp2 = in->sin6_addr; cmp2.s6_addr[15] = 0; if (IN6_ARE_ADDR_EQUAL(&cmp1, &cmp2)) { iface = in->sin6_addr.s6_addr[15]; } else { errno = ENETUNREACH; return -1; } break; } #endif default: SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown address family!\n"); errno = ENETUNREACH; return -1; } if (prt == 0) { SWRAP_LOG(SWRAP_LOG_WARN, "Port not set\n"); errno = EINVAL; return -1; } swrap_dir = socket_wrapper_dir(); if (swrap_dir == NULL) { errno = EINVAL; return -1; } if (is_bcast) { snprintf(un->sun_path, sizeof(un->sun_path), "%s/EINVAL", swrap_dir); SWRAP_LOG(SWRAP_LOG_DEBUG, "un path [%s]", un->sun_path); SAFE_FREE(swrap_dir); /* the caller need to do more processing */ return 0; } snprintf(un->sun_path, sizeof(un->sun_path), "%s/"SOCKET_FORMAT, swrap_dir, type, iface, prt); SWRAP_LOG(SWRAP_LOG_DEBUG, "un path [%s]", un->sun_path); SAFE_FREE(swrap_dir); return 0; } static int convert_in_un_alloc(struct socket_info *si, const struct sockaddr *inaddr, struct sockaddr_un *un, int *bcast) { char type = '\0'; unsigned int prt; unsigned int iface; struct stat st; int is_bcast = 0; char *swrap_dir = NULL; if (bcast) *bcast = 0; switch (si->family) { case AF_INET: { const struct sockaddr_in *in = (const struct sockaddr_in *)(const void *)inaddr; unsigned int addr = ntohl(in->sin_addr.s_addr); char u_type = '\0'; char d_type = '\0'; char b_type = '\0'; char a_type = '\0'; prt = ntohs(in->sin_port); switch (si->type) { case SOCK_STREAM: u_type = SOCKET_TYPE_CHAR_TCP; d_type = SOCKET_TYPE_CHAR_TCP; break; case SOCK_DGRAM: u_type = SOCKET_TYPE_CHAR_UDP; d_type = SOCKET_TYPE_CHAR_UDP; a_type = SOCKET_TYPE_CHAR_UDP; b_type = SOCKET_TYPE_CHAR_UDP; break; default: SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown socket type!\n"); errno = ESOCKTNOSUPPORT; return -1; } if (addr == 0) { /* 0.0.0.0 */ is_bcast = 0; type = d_type; iface = socket_wrapper_default_iface(); } else if (a_type && addr == 0xFFFFFFFF) { /* 255.255.255.255 only udp */ is_bcast = 2; type = a_type; iface = socket_wrapper_default_iface(); } else if (b_type && addr == 0x7FFFFFFF) { /* 127.255.255.255 only udp */ is_bcast = 1; type = b_type; iface = socket_wrapper_default_iface(); } else if ((addr & 0xFFFFFF00) == 0x7F000000) { /* 127.0.0.X */ is_bcast = 0; type = u_type; iface = (addr & 0x000000FF); } else { errno = EADDRNOTAVAIL; return -1; } /* Store the bind address for connect() */ if (si->bindname.sa_socklen == 0) { struct sockaddr_in bind_in; socklen_t blen = sizeof(struct sockaddr_in); ZERO_STRUCT(bind_in); bind_in.sin_family = in->sin_family; bind_in.sin_port = in->sin_port; bind_in.sin_addr.s_addr = htonl(0x7F000000 | iface); si->bindname.sa_socklen = blen; memcpy(&si->bindname.sa.in, &bind_in, blen); } break; } #ifdef HAVE_IPV6 case AF_INET6: { const struct sockaddr_in6 *in = (const struct sockaddr_in6 *)(const void *)inaddr; struct in6_addr cmp1, cmp2; switch (si->type) { case SOCK_STREAM: type = SOCKET_TYPE_CHAR_TCP_V6; break; case SOCK_DGRAM: type = SOCKET_TYPE_CHAR_UDP_V6; break; default: SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown socket type!\n"); errno = ESOCKTNOSUPPORT; return -1; } /* XXX no multicast/broadcast */ prt = ntohs(in->sin6_port); cmp1 = *swrap_ipv6(); cmp2 = in->sin6_addr; cmp2.s6_addr[15] = 0; if (IN6_IS_ADDR_UNSPECIFIED(&in->sin6_addr)) { iface = socket_wrapper_default_iface(); } else if (IN6_ARE_ADDR_EQUAL(&cmp1, &cmp2)) { iface = in->sin6_addr.s6_addr[15]; } else { errno = EADDRNOTAVAIL; return -1; } /* Store the bind address for connect() */ if (si->bindname.sa_socklen == 0) { struct sockaddr_in6 bind_in; socklen_t blen = sizeof(struct sockaddr_in6); ZERO_STRUCT(bind_in); bind_in.sin6_family = in->sin6_family; bind_in.sin6_port = in->sin6_port; bind_in.sin6_addr = *swrap_ipv6(); bind_in.sin6_addr.s6_addr[15] = iface; memcpy(&si->bindname.sa.in6, &bind_in, blen); si->bindname.sa_socklen = blen; } break; } #endif default: SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown address family\n"); errno = EADDRNOTAVAIL; return -1; } if (bcast) *bcast = is_bcast; if (iface == 0 || iface > MAX_WRAPPED_INTERFACES) { errno = EINVAL; return -1; } swrap_dir = socket_wrapper_dir(); if (swrap_dir == NULL) { errno = EINVAL; return -1; } if (prt == 0) { /* handle auto-allocation of ephemeral ports */ for (prt = 5001; prt < 10000; prt++) { snprintf(un->sun_path, sizeof(un->sun_path), "%s/"SOCKET_FORMAT, swrap_dir, type, iface, prt); if (stat(un->sun_path, &st) == 0) continue; set_port(si->family, prt, &si->myname); set_port(si->family, prt, &si->bindname); break; } if (prt == 10000) { errno = ENFILE; SAFE_FREE(swrap_dir); return -1; } } snprintf(un->sun_path, sizeof(un->sun_path), "%s/"SOCKET_FORMAT, swrap_dir, type, iface, prt); SWRAP_LOG(SWRAP_LOG_DEBUG, "un path [%s]", un->sun_path); SAFE_FREE(swrap_dir); return 0; } static struct socket_info *find_socket_info(int fd) { int idx = find_socket_info_index(fd); if (idx == -1) { return NULL; } return swrap_get_socket_info(idx); } #if 0 /* FIXME */ static bool check_addr_port_in_use(const struct sockaddr *sa, socklen_t len) { struct socket_info_fd *f; const struct socket_info *last_s = NULL; /* first catch invalid input */ switch (sa->sa_family) { case AF_INET: if (len < sizeof(struct sockaddr_in)) { return false; } break; #ifdef HAVE_IPV6 case AF_INET6: if (len < sizeof(struct sockaddr_in6)) { return false; } break; #endif default: return false; break; } for (f = socket_fds; f; f = f->next) { struct socket_info *s = swrap_get_socket_info(f->si_index); if (s == last_s) { continue; } last_s = s; if (s->myname == NULL) { continue; } if (s->myname->sa_family != sa->sa_family) { continue; } switch (s->myname->sa_family) { case AF_INET: { struct sockaddr_in *sin1, *sin2; sin1 = (struct sockaddr_in *)s->myname; sin2 = (struct sockaddr_in *)sa; if (sin1->sin_addr.s_addr == htonl(INADDR_ANY)) { continue; } if (sin1->sin_port != sin2->sin_port) { continue; } if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr) { continue; } /* found */ return true; break; } #ifdef HAVE_IPV6 case AF_INET6: { struct sockaddr_in6 *sin1, *sin2; sin1 = (struct sockaddr_in6 *)s->myname; sin2 = (struct sockaddr_in6 *)sa; if (sin1->sin6_port != sin2->sin6_port) { continue; } if (!IN6_ARE_ADDR_EQUAL(&sin1->sin6_addr, &sin2->sin6_addr)) { continue; } /* found */ return true; break; } #endif default: continue; break; } } return false; } #endif static void swrap_remove_stale(int fd) { struct socket_info *si; int si_index; SWRAP_LOG(SWRAP_LOG_TRACE, "remove stale wrapper for %d", fd); swrap_mutex_lock(&socket_reset_mutex); si_index = find_socket_info_index(fd); if (si_index == -1) { swrap_mutex_unlock(&socket_reset_mutex); return; } reset_socket_info_index(fd); si = swrap_get_socket_info(si_index); swrap_mutex_lock(&first_free_mutex); SWRAP_LOCK_SI(si); swrap_dec_refcount(si); if (swrap_get_refcount(si) > 0) { goto out; } if (si->un_addr.sun_path[0] != '\0') { unlink(si->un_addr.sun_path); } swrap_set_next_free(si, first_free); first_free = si_index; out: SWRAP_UNLOCK_SI(si); swrap_mutex_unlock(&first_free_mutex); swrap_mutex_unlock(&socket_reset_mutex); } static int sockaddr_convert_to_un(struct socket_info *si, const struct sockaddr *in_addr, socklen_t in_len, struct sockaddr_un *out_addr, int alloc_sock, int *bcast) { struct sockaddr *out = (struct sockaddr *)(void *)out_addr; (void) in_len; /* unused */ if (out_addr == NULL) { return 0; } out->sa_family = AF_UNIX; #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN out->sa_len = sizeof(*out_addr); #endif switch (in_addr->sa_family) { case AF_UNSPEC: { const struct sockaddr_in *sin; if (si->family != AF_INET) { break; } if (in_len < sizeof(struct sockaddr_in)) { break; } sin = (const struct sockaddr_in *)(const void *)in_addr; if(sin->sin_addr.s_addr != htonl(INADDR_ANY)) { break; } /* * Note: in the special case of AF_UNSPEC and INADDR_ANY, * AF_UNSPEC is mapped to AF_INET and must be treated here. */ FALL_THROUGH; } case AF_INET: #ifdef HAVE_IPV6 case AF_INET6: #endif switch (si->type) { case SOCK_STREAM: case SOCK_DGRAM: break; default: SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown socket type!\n"); errno = ESOCKTNOSUPPORT; return -1; } if (alloc_sock) { return convert_in_un_alloc(si, in_addr, out_addr, bcast); } else { return convert_in_un_remote(si, in_addr, out_addr, bcast); } default: break; } errno = EAFNOSUPPORT; SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown address family\n"); return -1; } static int sockaddr_convert_from_un(const struct socket_info *si, const struct sockaddr_un *in_addr, socklen_t un_addrlen, int family, struct sockaddr *out_addr, socklen_t *out_addrlen) { int ret; if (out_addr == NULL || out_addrlen == NULL) return 0; if (un_addrlen == 0) { *out_addrlen = 0; return 0; } switch (family) { case AF_INET: #ifdef HAVE_IPV6 case AF_INET6: #endif switch (si->type) { case SOCK_STREAM: case SOCK_DGRAM: break; default: SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown socket type!\n"); errno = ESOCKTNOSUPPORT; return -1; } ret = convert_un_in(in_addr, out_addr, out_addrlen); #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN out_addr->sa_len = *out_addrlen; #endif return ret; default: break; } SWRAP_LOG(SWRAP_LOG_ERROR, "Unknown address family\n"); errno = EAFNOSUPPORT; return -1; } enum swrap_packet_type { SWRAP_CONNECT_SEND, SWRAP_CONNECT_UNREACH, SWRAP_CONNECT_RECV, SWRAP_CONNECT_ACK, SWRAP_ACCEPT_SEND, SWRAP_ACCEPT_RECV, SWRAP_ACCEPT_ACK, SWRAP_RECVFROM, SWRAP_SENDTO, SWRAP_SENDTO_UNREACH, SWRAP_PENDING_RST, SWRAP_RECV, SWRAP_RECV_RST, SWRAP_SEND, SWRAP_SEND_RST, SWRAP_CLOSE_SEND, SWRAP_CLOSE_RECV, SWRAP_CLOSE_ACK, }; struct swrap_file_hdr { uint32_t magic; uint16_t version_major; uint16_t version_minor; int32_t timezone; uint32_t sigfigs; uint32_t frame_max_len; #define SWRAP_FRAME_LENGTH_MAX 0xFFFF uint32_t link_type; }; #define SWRAP_FILE_HDR_SIZE 24 struct swrap_packet_frame { uint32_t seconds; uint32_t micro_seconds; uint32_t recorded_length; uint32_t full_length; }; #define SWRAP_PACKET_FRAME_SIZE 16 union swrap_packet_ip { struct { uint8_t ver_hdrlen; uint8_t tos; uint16_t packet_length; uint16_t identification; uint8_t flags; uint8_t fragment; uint8_t ttl; uint8_t protocol; uint16_t hdr_checksum; uint32_t src_addr; uint32_t dest_addr; } v4; #define SWRAP_PACKET_IP_V4_SIZE 20 struct { uint8_t ver_prio; uint8_t flow_label_high; uint16_t flow_label_low; uint16_t payload_length; uint8_t next_header; uint8_t hop_limit; uint8_t src_addr[16]; uint8_t dest_addr[16]; } v6; #define SWRAP_PACKET_IP_V6_SIZE 40 }; #define SWRAP_PACKET_IP_SIZE 40 union swrap_packet_payload { struct { uint16_t source_port; uint16_t dest_port; uint32_t seq_num; uint32_t ack_num; uint8_t hdr_length; uint8_t control; uint16_t window; uint16_t checksum; uint16_t urg; } tcp; #define SWRAP_PACKET_PAYLOAD_TCP_SIZE 20 struct { uint16_t source_port; uint16_t dest_port; uint16_t length; uint16_t checksum; } udp; #define SWRAP_PACKET_PAYLOAD_UDP_SIZE 8 struct { uint8_t type; uint8_t code; uint16_t checksum; uint32_t unused; } icmp4; #define SWRAP_PACKET_PAYLOAD_ICMP4_SIZE 8 struct { uint8_t type; uint8_t code; uint16_t checksum; uint32_t unused; } icmp6; #define SWRAP_PACKET_PAYLOAD_ICMP6_SIZE 8 }; #define SWRAP_PACKET_PAYLOAD_SIZE 20 #define SWRAP_PACKET_MIN_ALLOC \ (SWRAP_PACKET_FRAME_SIZE + \ SWRAP_PACKET_IP_SIZE + \ SWRAP_PACKET_PAYLOAD_SIZE) static const char *swrap_pcap_init_file(void) { static int initialized = 0; static const char *s = NULL; static const struct swrap_file_hdr h; static const struct swrap_packet_frame f; static const union swrap_packet_ip i; static const union swrap_packet_payload p; if (initialized == 1) { return s; } initialized = 1; /* * TODO: don't use the structs use plain buffer offsets * and PUSH_U8(), PUSH_U16() and PUSH_U32() * * for now make sure we disable PCAP support * if the struct has alignment! */ if (sizeof(h) != SWRAP_FILE_HDR_SIZE) { return NULL; } if (sizeof(f) != SWRAP_PACKET_FRAME_SIZE) { return NULL; } if (sizeof(i) != SWRAP_PACKET_IP_SIZE) { return NULL; } if (sizeof(i.v4) != SWRAP_PACKET_IP_V4_SIZE) { return NULL; } if (sizeof(i.v6) != SWRAP_PACKET_IP_V6_SIZE) { return NULL; } if (sizeof(p) != SWRAP_PACKET_PAYLOAD_SIZE) { return NULL; } if (sizeof(p.tcp) != SWRAP_PACKET_PAYLOAD_TCP_SIZE) { return NULL; } if (sizeof(p.udp) != SWRAP_PACKET_PAYLOAD_UDP_SIZE) { return NULL; } if (sizeof(p.icmp4) != SWRAP_PACKET_PAYLOAD_ICMP4_SIZE) { return NULL; } if (sizeof(p.icmp6) != SWRAP_PACKET_PAYLOAD_ICMP6_SIZE) { return NULL; } s = getenv("SOCKET_WRAPPER_PCAP_FILE"); if (s == NULL) { return NULL; } if (strncmp(s, "./", 2) == 0) { s += 2; } return s; } static uint8_t *swrap_pcap_packet_init(struct timeval *tval, const struct sockaddr *src, const struct sockaddr *dest, int socket_type, const uint8_t *payload, size_t payload_len, unsigned long tcp_seqno, unsigned long tcp_ack, unsigned char tcp_ctl, int unreachable, size_t *_packet_len) { uint8_t *base = NULL; uint8_t *buf = NULL; union { uint8_t *ptr; struct swrap_packet_frame *frame; } f; union { uint8_t *ptr; union swrap_packet_ip *ip; } i; union swrap_packet_payload *pay; size_t packet_len; size_t alloc_len; size_t nonwire_len = sizeof(struct swrap_packet_frame); size_t wire_hdr_len = 0; size_t wire_len = 0; size_t ip_hdr_len = 0; size_t icmp_hdr_len = 0; size_t icmp_truncate_len = 0; uint8_t protocol = 0, icmp_protocol = 0; const struct sockaddr_in *src_in = NULL; const struct sockaddr_in *dest_in = NULL; #ifdef HAVE_IPV6 const struct sockaddr_in6 *src_in6 = NULL; const struct sockaddr_in6 *dest_in6 = NULL; #endif uint16_t src_port; uint16_t dest_port; switch (src->sa_family) { case AF_INET: src_in = (const struct sockaddr_in *)(const void *)src; dest_in = (const struct sockaddr_in *)(const void *)dest; src_port = src_in->sin_port; dest_port = dest_in->sin_port; ip_hdr_len = sizeof(i.ip->v4); break; #ifdef HAVE_IPV6 case AF_INET6: src_in6 = (const struct sockaddr_in6 *)(const void *)src; dest_in6 = (const struct sockaddr_in6 *)(const void *)dest; src_port = src_in6->sin6_port; dest_port = dest_in6->sin6_port; ip_hdr_len = sizeof(i.ip->v6); break; #endif default: return NULL; } switch (socket_type) { case SOCK_STREAM: protocol = 0x06; /* TCP */ wire_hdr_len = ip_hdr_len + sizeof(pay->tcp); wire_len = wire_hdr_len + payload_len; break; case SOCK_DGRAM: protocol = 0x11; /* UDP */ wire_hdr_len = ip_hdr_len + sizeof(pay->udp); wire_len = wire_hdr_len + payload_len; break; default: return NULL; } if (unreachable) { icmp_protocol = protocol; switch (src->sa_family) { case AF_INET: protocol = 0x01; /* ICMPv4 */ icmp_hdr_len = ip_hdr_len + sizeof(pay->icmp4); break; #ifdef HAVE_IPV6 case AF_INET6: protocol = 0x3A; /* ICMPv6 */ icmp_hdr_len = ip_hdr_len + sizeof(pay->icmp6); break; #endif } if (wire_len > 64 ) { icmp_truncate_len = wire_len - 64; } wire_len += icmp_hdr_len; } packet_len = nonwire_len + wire_len; alloc_len = packet_len; if (alloc_len < SWRAP_PACKET_MIN_ALLOC) { alloc_len = SWRAP_PACKET_MIN_ALLOC; } base = (uint8_t *)calloc(1, alloc_len); if (base == NULL) { return NULL; } buf = base; f.ptr = buf; f.frame->seconds = tval->tv_sec; f.frame->micro_seconds = tval->tv_usec; f.frame->recorded_length = wire_len - icmp_truncate_len; f.frame->full_length = wire_len - icmp_truncate_len; buf += SWRAP_PACKET_FRAME_SIZE; i.ptr = buf; switch (src->sa_family) { case AF_INET: if (src_in == NULL || dest_in == NULL) { SAFE_FREE(base); return NULL; } i.ip->v4.ver_hdrlen = 0x45; /* version 4 and 5 * 32 bit words */ i.ip->v4.tos = 0x00; i.ip->v4.packet_length = htons(wire_len - icmp_truncate_len); i.ip->v4.identification = htons(0xFFFF); i.ip->v4.flags = 0x40; /* BIT 1 set - means don't fragment */ i.ip->v4.fragment = htons(0x0000); i.ip->v4.ttl = 0xFF; i.ip->v4.protocol = protocol; i.ip->v4.hdr_checksum = htons(0x0000); i.ip->v4.src_addr = src_in->sin_addr.s_addr; i.ip->v4.dest_addr = dest_in->sin_addr.s_addr; buf += SWRAP_PACKET_IP_V4_SIZE; break; #ifdef HAVE_IPV6 case AF_INET6: if (src_in6 == NULL || dest_in6 == NULL) { SAFE_FREE(base); return NULL; } i.ip->v6.ver_prio = 0x60; /* version 4 and 5 * 32 bit words */ i.ip->v6.flow_label_high = 0x00; i.ip->v6.flow_label_low = 0x0000; i.ip->v6.payload_length = htons(wire_len - icmp_truncate_len); /* TODO */ i.ip->v6.next_header = protocol; memcpy(i.ip->v6.src_addr, src_in6->sin6_addr.s6_addr, 16); memcpy(i.ip->v6.dest_addr, dest_in6->sin6_addr.s6_addr, 16); buf += SWRAP_PACKET_IP_V6_SIZE; break; #endif } if (unreachable) { pay = (union swrap_packet_payload *)(void *)buf; switch (src->sa_family) { case AF_INET: pay->icmp4.type = 0x03; /* destination unreachable */ pay->icmp4.code = 0x01; /* host unreachable */ pay->icmp4.checksum = htons(0x0000); pay->icmp4.unused = htonl(0x00000000); buf += SWRAP_PACKET_PAYLOAD_ICMP4_SIZE; /* set the ip header in the ICMP payload */ i.ptr = buf; i.ip->v4.ver_hdrlen = 0x45; /* version 4 and 5 * 32 bit words */ i.ip->v4.tos = 0x00; i.ip->v4.packet_length = htons(wire_len - icmp_hdr_len); i.ip->v4.identification = htons(0xFFFF); i.ip->v4.flags = 0x40; /* BIT 1 set - means don't fragment */ i.ip->v4.fragment = htons(0x0000); i.ip->v4.ttl = 0xFF; i.ip->v4.protocol = icmp_protocol; i.ip->v4.hdr_checksum = htons(0x0000); i.ip->v4.src_addr = dest_in->sin_addr.s_addr; i.ip->v4.dest_addr = src_in->sin_addr.s_addr; buf += SWRAP_PACKET_IP_V4_SIZE; src_port = dest_in->sin_port; dest_port = src_in->sin_port; break; #ifdef HAVE_IPV6 case AF_INET6: pay->icmp6.type = 0x01; /* destination unreachable */ pay->icmp6.code = 0x03; /* address unreachable */ pay->icmp6.checksum = htons(0x0000); pay->icmp6.unused = htonl(0x00000000); buf += SWRAP_PACKET_PAYLOAD_ICMP6_SIZE; /* set the ip header in the ICMP payload */ i.ptr = buf; i.ip->v6.ver_prio = 0x60; /* version 4 and 5 * 32 bit words */ i.ip->v6.flow_label_high = 0x00; i.ip->v6.flow_label_low = 0x0000; i.ip->v6.payload_length = htons(wire_len - icmp_truncate_len); /* TODO */ i.ip->v6.next_header = protocol; memcpy(i.ip->v6.src_addr, dest_in6->sin6_addr.s6_addr, 16); memcpy(i.ip->v6.dest_addr, src_in6->sin6_addr.s6_addr, 16); buf += SWRAP_PACKET_IP_V6_SIZE; src_port = dest_in6->sin6_port; dest_port = src_in6->sin6_port; break; #endif } } pay = (union swrap_packet_payload *)(void *)buf; switch (socket_type) { case SOCK_STREAM: pay->tcp.source_port = src_port; pay->tcp.dest_port = dest_port; pay->tcp.seq_num = htonl(tcp_seqno); pay->tcp.ack_num = htonl(tcp_ack); pay->tcp.hdr_length = 0x50; /* 5 * 32 bit words */ pay->tcp.control = tcp_ctl; pay->tcp.window = htons(0x7FFF); pay->tcp.checksum = htons(0x0000); pay->tcp.urg = htons(0x0000); buf += SWRAP_PACKET_PAYLOAD_TCP_SIZE; break; case SOCK_DGRAM: pay->udp.source_port = src_port; pay->udp.dest_port = dest_port; pay->udp.length = htons(8 + payload_len); pay->udp.checksum = htons(0x0000); buf += SWRAP_PACKET_PAYLOAD_UDP_SIZE; break; } if (payload && payload_len > 0) { memcpy(buf, payload, payload_len); } *_packet_len = packet_len - icmp_truncate_len; return base; } static int swrap_pcap_get_fd(const char *fname) { static int fd = -1; if (fd != -1) { return fd; } fd = libc_open(fname, O_WRONLY|O_CREAT|O_EXCL|O_APPEND, 0644); if (fd != -1) { struct swrap_file_hdr file_hdr; file_hdr.magic = 0xA1B2C3D4; file_hdr.version_major = 0x0002; file_hdr.version_minor = 0x0004; file_hdr.timezone = 0x00000000; file_hdr.sigfigs = 0x00000000; file_hdr.frame_max_len = SWRAP_FRAME_LENGTH_MAX; file_hdr.link_type = 0x0065; /* 101 RAW IP */ if (write(fd, &file_hdr, sizeof(file_hdr)) != sizeof(file_hdr)) { close(fd); fd = -1; } return fd; } fd = libc_open(fname, O_WRONLY|O_APPEND, 0644); return fd; } static uint8_t *swrap_pcap_marshall_packet(struct socket_info *si, const struct sockaddr *addr, enum swrap_packet_type type, const void *buf, size_t len, size_t *packet_len) { const struct sockaddr *src_addr; const struct sockaddr *dest_addr; unsigned long tcp_seqno = 0; unsigned long tcp_ack = 0; unsigned char tcp_ctl = 0; int unreachable = 0; struct timeval tv; switch (si->family) { case AF_INET: break; #ifdef HAVE_IPV6 case AF_INET6: break; #endif default: return NULL; } switch (type) { case SWRAP_CONNECT_SEND: if (si->type != SOCK_STREAM) { return NULL; } src_addr = &si->myname.sa.s; dest_addr = addr; tcp_seqno = si->io.pck_snd; tcp_ack = si->io.pck_rcv; tcp_ctl = 0x02; /* SYN */ si->io.pck_snd += 1; break; case SWRAP_CONNECT_RECV: if (si->type != SOCK_STREAM) { return NULL; } dest_addr = &si->myname.sa.s; src_addr = addr; tcp_seqno = si->io.pck_rcv; tcp_ack = si->io.pck_snd; tcp_ctl = 0x12; /** SYN,ACK */ si->io.pck_rcv += 1; break; case SWRAP_CONNECT_UNREACH: if (si->type != SOCK_STREAM) { return NULL; } dest_addr = &si->myname.sa.s; src_addr = addr; /* Unreachable: resend the data of SWRAP_CONNECT_SEND */ tcp_seqno = si->io.pck_snd - 1; tcp_ack = si->io.pck_rcv; tcp_ctl = 0x02; /* SYN */ unreachable = 1; break; case SWRAP_CONNECT_ACK: if (si->type != SOCK_STREAM) { return NULL; } src_addr = &si->myname.sa.s; dest_addr = addr; tcp_seqno = si->io.pck_snd; tcp_ack = si->io.pck_rcv; tcp_ctl = 0x10; /* ACK */ break; case SWRAP_ACCEPT_SEND: if (si->type != SOCK_STREAM) { return NULL; } dest_addr = &si->myname.sa.s; src_addr = addr; tcp_seqno = si->io.pck_rcv; tcp_ack = si->io.pck_snd; tcp_ctl = 0x02; /* SYN */ si->io.pck_rcv += 1; break; case SWRAP_ACCEPT_RECV: if (si->type != SOCK_STREAM) { return NULL; } src_addr = &si->myname.sa.s; dest_addr = addr; tcp_seqno = si->io.pck_snd; tcp_ack = si->io.pck_rcv; tcp_ctl = 0x12; /* SYN,ACK */ si->io.pck_snd += 1; break; case SWRAP_ACCEPT_ACK: if (si->type != SOCK_STREAM) { return NULL; } dest_addr = &si->myname.sa.s; src_addr = addr; tcp_seqno = si->io.pck_rcv; tcp_ack = si->io.pck_snd; tcp_ctl = 0x10; /* ACK */ break; case SWRAP_SEND: src_addr = &si->myname.sa.s; dest_addr = &si->peername.sa.s; tcp_seqno = si->io.pck_snd; tcp_ack = si->io.pck_rcv; tcp_ctl = 0x18; /* PSH,ACK */ si->io.pck_snd += len; break; case SWRAP_SEND_RST: dest_addr = &si->myname.sa.s; src_addr = &si->peername.sa.s; if (si->type == SOCK_DGRAM) { return swrap_pcap_marshall_packet(si, &si->peername.sa.s, SWRAP_SENDTO_UNREACH, buf, len, packet_len); } tcp_seqno = si->io.pck_rcv; tcp_ack = si->io.pck_snd; tcp_ctl = 0x14; /** RST,ACK */ break; case SWRAP_PENDING_RST: dest_addr = &si->myname.sa.s; src_addr = &si->peername.sa.s; if (si->type == SOCK_DGRAM) { return NULL; } tcp_seqno = si->io.pck_rcv; tcp_ack = si->io.pck_snd; tcp_ctl = 0x14; /* RST,ACK */ break; case SWRAP_RECV: dest_addr = &si->myname.sa.s; src_addr = &si->peername.sa.s; tcp_seqno = si->io.pck_rcv; tcp_ack = si->io.pck_snd; tcp_ctl = 0x18; /* PSH,ACK */ si->io.pck_rcv += len; break; case SWRAP_RECV_RST: dest_addr = &si->myname.sa.s; src_addr = &si->peername.sa.s; if (si->type == SOCK_DGRAM) { return NULL; } tcp_seqno = si->io.pck_rcv; tcp_ack = si->io.pck_snd; tcp_ctl = 0x14; /* RST,ACK */ break; case SWRAP_SENDTO: src_addr = &si->myname.sa.s; dest_addr = addr; si->io.pck_snd += len; break; case SWRAP_SENDTO_UNREACH: dest_addr = &si->myname.sa.s; src_addr = addr; unreachable = 1; break; case SWRAP_RECVFROM: dest_addr = &si->myname.sa.s; src_addr = addr; si->io.pck_rcv += len; break; case SWRAP_CLOSE_SEND: if (si->type != SOCK_STREAM) { return NULL; } src_addr = &si->myname.sa.s; dest_addr = &si->peername.sa.s; tcp_seqno = si->io.pck_snd; tcp_ack = si->io.pck_rcv; tcp_ctl = 0x11; /* FIN, ACK */ si->io.pck_snd += 1; break; case SWRAP_CLOSE_RECV: if (si->type != SOCK_STREAM) { return NULL; } dest_addr = &si->myname.sa.s; src_addr = &si->peername.sa.s; tcp_seqno = si->io.pck_rcv; tcp_ack = si->io.pck_snd; tcp_ctl = 0x11; /* FIN,ACK */ si->io.pck_rcv += 1; break; case SWRAP_CLOSE_ACK: if (si->type != SOCK_STREAM) { return NULL; } src_addr = &si->myname.sa.s; dest_addr = &si->peername.sa.s; tcp_seqno = si->io.pck_snd; tcp_ack = si->io.pck_rcv; tcp_ctl = 0x10; /* ACK */ break; default: return NULL; } swrapGetTimeOfDay(&tv); return swrap_pcap_packet_init(&tv, src_addr, dest_addr, si->type, (const uint8_t *)buf, len, tcp_seqno, tcp_ack, tcp_ctl, unreachable, packet_len); } static void swrap_pcap_dump_packet(struct socket_info *si, const struct sockaddr *addr, enum swrap_packet_type type, const void *buf, size_t len) { const char *file_name; uint8_t *packet; size_t packet_len = 0; int fd; swrap_mutex_lock(&pcap_dump_mutex); file_name = swrap_pcap_init_file(); if (!file_name) { goto done; } packet = swrap_pcap_marshall_packet(si, addr, type, buf, len, &packet_len); if (packet == NULL) { goto done; } fd = swrap_pcap_get_fd(file_name); if (fd != -1) { if (write(fd, packet, packet_len) != (ssize_t)packet_len) { free(packet); goto done; } } free(packet); done: swrap_mutex_unlock(&pcap_dump_mutex); } /**************************************************************************** * SIGNALFD ***************************************************************************/ #ifdef HAVE_SIGNALFD static int swrap_signalfd(int fd, const sigset_t *mask, int flags) { int rc; rc = libc_signalfd(fd, mask, flags); if (rc != -1) { swrap_remove_stale(fd); } return rc; } int signalfd(int fd, const sigset_t *mask, int flags) { return swrap_signalfd(fd, mask, flags); } #endif /**************************************************************************** * SOCKET ***************************************************************************/ static int swrap_socket(int family, int type, int protocol) { struct socket_info *si = NULL; struct socket_info _si = { 0 }; int fd; int ret; int real_type = type; /* * Remove possible addition flags passed to socket() so * do not fail checking the type. * See https://lwn.net/Articles/281965/ */ #ifdef SOCK_CLOEXEC real_type &= ~SOCK_CLOEXEC; #endif #ifdef SOCK_NONBLOCK real_type &= ~SOCK_NONBLOCK; #endif if (!socket_wrapper_enabled()) { return libc_socket(family, type, protocol); } switch (family) { case AF_INET: #ifdef HAVE_IPV6 case AF_INET6: #endif break; #ifdef AF_NETLINK case AF_NETLINK: #endif /* AF_NETLINK */ #ifdef AF_PACKET case AF_PACKET: #endif /* AF_PACKET */ case AF_UNIX: return libc_socket(family, type, protocol); default: errno = EAFNOSUPPORT; return -1; } switch (real_type) { case SOCK_STREAM: break; case SOCK_DGRAM: break; default: errno = EPROTONOSUPPORT; return -1; } switch (protocol) { case 0: break; case 6: if (real_type == SOCK_STREAM) { break; } FALL_THROUGH; case 17: if (real_type == SOCK_DGRAM) { break; } FALL_THROUGH; default: errno = EPROTONOSUPPORT; return -1; } /* * We must call libc_socket with type, from the caller, not the version * we removed SOCK_CLOEXEC and SOCK_NONBLOCK from */ fd = libc_socket(AF_UNIX, type, 0); if (fd == -1) { return -1; } /* Check if we have a stale fd and remove it */ swrap_remove_stale(fd); si = &_si; si->family = family; /* however, the rest of the socket_wrapper code expects just * the type, not the flags */ si->type = real_type; si->protocol = protocol; /* * Setup myname so getsockname() can succeed to find out the socket * type. */ switch(si->family) { case AF_INET: { struct sockaddr_in sin = { .sin_family = AF_INET, }; si->myname.sa_socklen = sizeof(struct sockaddr_in); memcpy(&si->myname.sa.in, &sin, si->myname.sa_socklen); break; } #ifdef HAVE_IPV6 case AF_INET6: { struct sockaddr_in6 sin6 = { .sin6_family = AF_INET6, }; si->myname.sa_socklen = sizeof(struct sockaddr_in6); memcpy(&si->myname.sa.in6, &sin6, si->myname.sa_socklen); break; } #endif default: errno = EINVAL; return -1; } ret = swrap_create_socket(si, fd); if (ret == -1) { return -1; } SWRAP_LOG(SWRAP_LOG_TRACE, "Created %s socket for protocol %s, fd=%d", family == AF_INET ? "IPv4" : "IPv6", real_type == SOCK_DGRAM ? "UDP" : "TCP", fd); return fd; } int socket(int family, int type, int protocol) { return swrap_socket(family, type, protocol); } /**************************************************************************** * SOCKETPAIR ***************************************************************************/ static int swrap_socketpair(int family, int type, int protocol, int sv[2]) { int rc; rc = libc_socketpair(family, type, protocol, sv); if (rc != -1) { swrap_remove_stale(sv[0]); swrap_remove_stale(sv[1]); } return rc; } int socketpair(int family, int type, int protocol, int sv[2]) { return swrap_socketpair(family, type, protocol, sv); } /**************************************************************************** * SOCKETPAIR ***************************************************************************/ #ifdef HAVE_TIMERFD_CREATE static int swrap_timerfd_create(int clockid, int flags) { int fd; fd = libc_timerfd_create(clockid, flags); if (fd != -1) { swrap_remove_stale(fd); } return fd; } int timerfd_create(int clockid, int flags) { return swrap_timerfd_create(clockid, flags); } #endif /**************************************************************************** * PIPE ***************************************************************************/ static int swrap_pipe(int pipefd[2]) { int rc; rc = libc_pipe(pipefd); if (rc != -1) { swrap_remove_stale(pipefd[0]); swrap_remove_stale(pipefd[1]); } return rc; } int pipe(int pipefd[2]) { return swrap_pipe(pipefd); } /**************************************************************************** * ACCEPT ***************************************************************************/ static int swrap_accept(int s, struct sockaddr *addr, socklen_t *addrlen, int flags) { struct socket_info *parent_si, *child_si; struct socket_info new_si = { 0 }; int fd; int idx; struct swrap_address un_addr = { .sa_socklen = sizeof(struct sockaddr_un), }; struct swrap_address un_my_addr = { .sa_socklen = sizeof(struct sockaddr_un), }; struct swrap_address in_addr = { .sa_socklen = sizeof(struct sockaddr_storage), }; struct swrap_address in_my_addr = { .sa_socklen = sizeof(struct sockaddr_storage), }; int ret; parent_si = find_socket_info(s); if (!parent_si) { #ifdef HAVE_ACCEPT4 return libc_accept4(s, addr, addrlen, flags); #else UNUSED(flags); return libc_accept(s, addr, addrlen); #endif } /* * prevent parent_si from being altered / closed * while we read it */ SWRAP_LOCK_SI(parent_si); /* * assume out sockaddr have the same size as the in parent * socket family */ in_addr.sa_socklen = socket_length(parent_si->family); if (in_addr.sa_socklen <= 0) { SWRAP_UNLOCK_SI(parent_si); errno = EINVAL; return -1; } SWRAP_UNLOCK_SI(parent_si); #ifdef HAVE_ACCEPT4 ret = libc_accept4(s, &un_addr.sa.s, &un_addr.sa_socklen, flags); #else UNUSED(flags); ret = libc_accept(s, &un_addr.sa.s, &un_addr.sa_socklen); #endif if (ret == -1) { if (errno == ENOTSOCK) { /* Remove stale fds */ swrap_remove_stale(s); } return ret; } fd = ret; SWRAP_LOCK_SI(parent_si); ret = sockaddr_convert_from_un(parent_si, &un_addr.sa.un, un_addr.sa_socklen, parent_si->family, &in_addr.sa.s, &in_addr.sa_socklen); if (ret == -1) { SWRAP_UNLOCK_SI(parent_si); close(fd); return ret; } child_si = &new_si; child_si->family = parent_si->family; child_si->type = parent_si->type; child_si->protocol = parent_si->protocol; child_si->bound = 1; child_si->is_server = 1; child_si->connected = 1; SWRAP_UNLOCK_SI(parent_si); child_si->peername = (struct swrap_address) { .sa_socklen = in_addr.sa_socklen, }; memcpy(&child_si->peername.sa.ss, &in_addr.sa.ss, in_addr.sa_socklen); if (addr != NULL && addrlen != NULL) { size_t copy_len = MIN(*addrlen, in_addr.sa_socklen); if (copy_len > 0) { memcpy(addr, &in_addr.sa.ss, copy_len); } *addrlen = in_addr.sa_socklen; } ret = libc_getsockname(fd, &un_my_addr.sa.s, &un_my_addr.sa_socklen); if (ret == -1) { close(fd); return ret; } ret = sockaddr_convert_from_un(child_si, &un_my_addr.sa.un, un_my_addr.sa_socklen, child_si->family, &in_my_addr.sa.s, &in_my_addr.sa_socklen); if (ret == -1) { close(fd); return ret; } SWRAP_LOG(SWRAP_LOG_TRACE, "accept() path=%s, fd=%d", un_my_addr.sa.un.sun_path, s); child_si->myname = (struct swrap_address) { .sa_socklen = in_my_addr.sa_socklen, }; memcpy(&child_si->myname.sa.ss, &in_my_addr.sa.ss, in_my_addr.sa_socklen); idx = swrap_create_socket(&new_si, fd); if (idx == -1) { close (fd); return -1; } if (addr != NULL) { struct socket_info *si = swrap_get_socket_info(idx); SWRAP_LOCK_SI(si); swrap_pcap_dump_packet(si, addr, SWRAP_ACCEPT_SEND, NULL, 0); swrap_pcap_dump_packet(si, addr, SWRAP_ACCEPT_RECV, NULL, 0); swrap_pcap_dump_packet(si, addr, SWRAP_ACCEPT_ACK, NULL, 0); SWRAP_UNLOCK_SI(si); } return fd; } #ifdef HAVE_ACCEPT4 int accept4(int s, struct sockaddr *addr, socklen_t *addrlen, int flags) { return swrap_accept(s, addr, (socklen_t *)addrlen, flags); } #endif #ifdef HAVE_ACCEPT_PSOCKLEN_T int accept(int s, struct sockaddr *addr, Psocklen_t addrlen) #else int accept(int s, struct sockaddr *addr, socklen_t *addrlen) #endif { return swrap_accept(s, addr, (socklen_t *)addrlen, 0); } static int autobind_start_init; static int autobind_start; /* using sendto() or connect() on an unbound socket would give the recipient no way to reply, as unlike UDP and TCP, a unix domain socket can't auto-assign ephemeral port numbers, so we need to assign it here. Note: this might change the family from ipv6 to ipv4 */ static int swrap_auto_bind(int fd, struct socket_info *si, int family) { struct swrap_address un_addr = { .sa_socklen = sizeof(struct sockaddr_un), }; int i; char type; int ret; int port; struct stat st; char *swrap_dir = NULL; swrap_mutex_lock(&autobind_start_mutex); if (autobind_start_init != 1) { autobind_start_init = 1; autobind_start = getpid(); autobind_start %= 50000; autobind_start += 10000; } un_addr.sa.un.sun_family = AF_UNIX; switch (family) { case AF_INET: { struct sockaddr_in in; switch (si->type) { case SOCK_STREAM: type = SOCKET_TYPE_CHAR_TCP; break; case SOCK_DGRAM: type = SOCKET_TYPE_CHAR_UDP; break; default: errno = ESOCKTNOSUPPORT; ret = -1; goto done; } memset(&in, 0, sizeof(in)); in.sin_family = AF_INET; in.sin_addr.s_addr = htonl(127<<24 | socket_wrapper_default_iface()); si->myname = (struct swrap_address) { .sa_socklen = sizeof(in), }; memcpy(&si->myname.sa.in, &in, si->myname.sa_socklen); break; } #ifdef HAVE_IPV6 case AF_INET6: { struct sockaddr_in6 in6; if (si->family != family) { errno = ENETUNREACH; ret = -1; goto done; } switch (si->type) { case SOCK_STREAM: type = SOCKET_TYPE_CHAR_TCP_V6; break; case SOCK_DGRAM: type = SOCKET_TYPE_CHAR_UDP_V6; break; default: errno = ESOCKTNOSUPPORT; ret = -1; goto done; } memset(&in6, 0, sizeof(in6)); in6.sin6_family = AF_INET6; in6.sin6_addr = *swrap_ipv6(); in6.sin6_addr.s6_addr[15] = socket_wrapper_default_iface(); si->myname = (struct swrap_address) { .sa_socklen = sizeof(in6), }; memcpy(&si->myname.sa.in6, &in6, si->myname.sa_socklen); break; } #endif default: errno = ESOCKTNOSUPPORT; ret = -1; goto done; } if (autobind_start > 60000) { autobind_start = 10000; } swrap_dir = socket_wrapper_dir(); if (swrap_dir == NULL) { errno = EINVAL; ret = -1; goto done; } for (i = 0; i < SOCKET_MAX_SOCKETS; i++) { port = autobind_start + i; snprintf(un_addr.sa.un.sun_path, sizeof(un_addr.sa.un.sun_path), "%s/"SOCKET_FORMAT, swrap_dir, type, socket_wrapper_default_iface(), port); if (stat(un_addr.sa.un.sun_path, &st) == 0) continue; ret = libc_bind(fd, &un_addr.sa.s, un_addr.sa_socklen); if (ret == -1) { goto done; } si->un_addr = un_addr.sa.un; si->bound = 1; autobind_start = port + 1; break; } if (i == SOCKET_MAX_SOCKETS) { SWRAP_LOG(SWRAP_LOG_ERROR, "Too many open unix sockets (%u) for " "interface "SOCKET_FORMAT, SOCKET_MAX_SOCKETS, type, socket_wrapper_default_iface(), 0); errno = ENFILE; ret = -1; goto done; } si->family = family; set_port(si->family, port, &si->myname); ret = 0; done: SAFE_FREE(swrap_dir); swrap_mutex_unlock(&autobind_start_mutex); return ret; } /**************************************************************************** * CONNECT ***************************************************************************/ static int swrap_connect(int s, const struct sockaddr *serv_addr, socklen_t addrlen) { int ret; struct swrap_address un_addr = { .sa_socklen = sizeof(struct sockaddr_un), }; struct socket_info *si = find_socket_info(s); int bcast = 0; if (!si) { return libc_connect(s, serv_addr, addrlen); } SWRAP_LOCK_SI(si); if (si->bound == 0) { ret = swrap_auto_bind(s, si, serv_addr->sa_family); if (ret == -1) { goto done; } } if (si->family != serv_addr->sa_family) { errno = EINVAL; ret = -1; goto done; } ret = sockaddr_convert_to_un(si, serv_addr, addrlen, &un_addr.sa.un, 0, &bcast); if (ret == -1) { goto done; } if (bcast) { errno = ENETUNREACH; ret = -1; goto done; } if (si->type == SOCK_DGRAM) { si->defer_connect = 1; ret = 0; } else { swrap_pcap_dump_packet(si, serv_addr, SWRAP_CONNECT_SEND, NULL, 0); ret = libc_connect(s, &un_addr.sa.s, un_addr.sa_socklen); } SWRAP_LOG(SWRAP_LOG_TRACE, "connect() path=%s, fd=%d", un_addr.sa.un.sun_path, s); /* to give better errors */ if (ret == -1 && errno == ENOENT) { errno = EHOSTUNREACH; } if (ret == 0) { si->peername = (struct swrap_address) { .sa_socklen = addrlen, }; memcpy(&si->peername.sa.ss, serv_addr, addrlen); si->connected = 1; /* * When we connect() on a socket than we have to bind the * outgoing connection on the interface we use for the * transport. We already bound it on the right interface * but here we have to update the name so getsockname() * returns correct information. */ if (si->bindname.sa_socklen > 0) { si->myname = (struct swrap_address) { .sa_socklen = si->bindname.sa_socklen, }; memcpy(&si->myname.sa.ss, &si->bindname.sa.ss, si->bindname.sa_socklen); /* Cleanup bindname */ si->bindname = (struct swrap_address) { .sa_socklen = 0, }; } swrap_pcap_dump_packet(si, serv_addr, SWRAP_CONNECT_RECV, NULL, 0); swrap_pcap_dump_packet(si, serv_addr, SWRAP_CONNECT_ACK, NULL, 0); } else { swrap_pcap_dump_packet(si, serv_addr, SWRAP_CONNECT_UNREACH, NULL, 0); } done: SWRAP_UNLOCK_SI(si); return ret; } int connect(int s, const struct sockaddr *serv_addr, socklen_t addrlen) { return swrap_connect(s, serv_addr, addrlen); } /**************************************************************************** * BIND ***************************************************************************/ static int swrap_bind(int s, const struct sockaddr *myaddr, socklen_t addrlen) { int ret; struct swrap_address un_addr = { .sa_socklen = sizeof(struct sockaddr_un), }; struct socket_info *si = find_socket_info(s); int bind_error = 0; #if 0 /* FIXME */ bool in_use; #endif if (!si) { return libc_bind(s, myaddr, addrlen); } SWRAP_LOCK_SI(si); switch (si->family) { case AF_INET: { const struct sockaddr_in *sin; if (addrlen < sizeof(struct sockaddr_in)) { bind_error = EINVAL; break; } sin = (const struct sockaddr_in *)(const void *)myaddr; if (sin->sin_family != AF_INET) { bind_error = EAFNOSUPPORT; } /* special case for AF_UNSPEC */ if (sin->sin_family == AF_UNSPEC && (sin->sin_addr.s_addr == htonl(INADDR_ANY))) { bind_error = 0; } break; } #ifdef HAVE_IPV6 case AF_INET6: { const struct sockaddr_in6 *sin6; if (addrlen < sizeof(struct sockaddr_in6)) { bind_error = EINVAL; break; } sin6 = (const struct sockaddr_in6 *)(const void *)myaddr; if (sin6->sin6_family != AF_INET6) { bind_error = EAFNOSUPPORT; } break; } #endif default: bind_error = EINVAL; break; } if (bind_error != 0) { errno = bind_error; ret = -1; goto out; } #if 0 /* FIXME */ in_use = check_addr_port_in_use(myaddr, addrlen); if (in_use) { errno = EADDRINUSE; ret = -1; goto out; } #endif si->myname.sa_socklen = addrlen; memcpy(&si->myname.sa.ss, myaddr, addrlen); ret = sockaddr_convert_to_un(si, myaddr, addrlen, &un_addr.sa.un, 1, &si->bcast); if (ret == -1) { goto out; } unlink(un_addr.sa.un.sun_path); ret = libc_bind(s, &un_addr.sa.s, un_addr.sa_socklen); SWRAP_LOG(SWRAP_LOG_TRACE, "bind() path=%s, fd=%d", un_addr.sa.un.sun_path, s); if (ret == 0) { si->bound = 1; } out: SWRAP_UNLOCK_SI(si); return ret; } int bind(int s, const struct sockaddr *myaddr, socklen_t addrlen) { return swrap_bind(s, myaddr, addrlen); } /**************************************************************************** * BINDRESVPORT ***************************************************************************/ #ifdef HAVE_BINDRESVPORT static int swrap_getsockname(int s, struct sockaddr *name, socklen_t *addrlen); static int swrap_bindresvport_sa(int sd, struct sockaddr *sa) { struct swrap_address myaddr = { .sa_socklen = sizeof(struct sockaddr_storage), }; socklen_t salen; static uint16_t port; uint16_t i; int rc = -1; int af; #define SWRAP_STARTPORT 600 #define SWRAP_ENDPORT (IPPORT_RESERVED - 1) #define SWRAP_NPORTS (SWRAP_ENDPORT - SWRAP_STARTPORT + 1) if (port == 0) { port = (getpid() % SWRAP_NPORTS) + SWRAP_STARTPORT; } if (sa == NULL) { salen = myaddr.sa_socklen; sa = &myaddr.sa.s; rc = swrap_getsockname(sd, &myaddr.sa.s, &salen); if (rc < 0) { return -1; } af = sa->sa_family; memset(&myaddr.sa.ss, 0, salen); } else { af = sa->sa_family; } for (i = 0; i < SWRAP_NPORTS; i++, port++) { switch(af) { case AF_INET: { struct sockaddr_in *sinp = (struct sockaddr_in *)(void *)sa; salen = sizeof(struct sockaddr_in); sinp->sin_port = htons(port); break; } case AF_INET6: { struct sockaddr_in6 *sin6p = (struct sockaddr_in6 *)(void *)sa; salen = sizeof(struct sockaddr_in6); sin6p->sin6_port = htons(port); break; } default: errno = EAFNOSUPPORT; return -1; } sa->sa_family = af; if (port > SWRAP_ENDPORT) { port = SWRAP_STARTPORT; } rc = swrap_bind(sd, (struct sockaddr *)sa, salen); if (rc == 0 || errno != EADDRINUSE) { break; } } return rc; } int bindresvport(int sockfd, struct sockaddr_in *sinp) { return swrap_bindresvport_sa(sockfd, (struct sockaddr *)sinp); } #endif /**************************************************************************** * LISTEN ***************************************************************************/ static int swrap_listen(int s, int backlog) { int ret; struct socket_info *si = find_socket_info(s); if (!si) { return libc_listen(s, backlog); } SWRAP_LOCK_SI(si); if (si->bound == 0) { ret = swrap_auto_bind(s, si, si->family); if (ret == -1) { errno = EADDRINUSE; goto out; } } ret = libc_listen(s, backlog); out: SWRAP_UNLOCK_SI(si); return ret; } int listen(int s, int backlog) { return swrap_listen(s, backlog); } /**************************************************************************** * FOPEN ***************************************************************************/ static FILE *swrap_fopen(const char *name, const char *mode) { FILE *fp; fp = libc_fopen(name, mode); if (fp != NULL) { int fd = fileno(fp); swrap_remove_stale(fd); } return fp; } FILE *fopen(const char *name, const char *mode) { return swrap_fopen(name, mode); } /**************************************************************************** * FOPEN64 ***************************************************************************/ #ifdef HAVE_FOPEN64 static FILE *swrap_fopen64(const char *name, const char *mode) { FILE *fp; fp = libc_fopen64(name, mode); if (fp != NULL) { int fd = fileno(fp); swrap_remove_stale(fd); } return fp; } FILE *fopen64(const char *name, const char *mode) { return swrap_fopen64(name, mode); } #endif /* HAVE_FOPEN64 */ /**************************************************************************** * OPEN ***************************************************************************/ static int swrap_vopen(const char *pathname, int flags, va_list ap) { int ret; ret = libc_vopen(pathname, flags, ap); if (ret != -1) { /* * There are methods for closing descriptors (libc-internal code * paths, direct syscalls) which close descriptors in ways that * we can't intercept, so try to recover when we notice that * that's happened */ swrap_remove_stale(ret); } return ret; } int open(const char *pathname, int flags, ...) { va_list ap; int fd; va_start(ap, flags); fd = swrap_vopen(pathname, flags, ap); va_end(ap); return fd; } /**************************************************************************** * OPEN64 ***************************************************************************/ #ifdef HAVE_OPEN64 static int swrap_vopen64(const char *pathname, int flags, va_list ap) { int ret; ret = libc_vopen64(pathname, flags, ap); if (ret != -1) { /* * There are methods for closing descriptors (libc-internal code * paths, direct syscalls) which close descriptors in ways that * we can't intercept, so try to recover when we notice that * that's happened */ swrap_remove_stale(ret); } return ret; } int open64(const char *pathname, int flags, ...) { va_list ap; int fd; va_start(ap, flags); fd = swrap_vopen64(pathname, flags, ap); va_end(ap); return fd; } #endif /* HAVE_OPEN64 */ /**************************************************************************** * OPENAT ***************************************************************************/ static int swrap_vopenat(int dirfd, const char *path, int flags, va_list ap) { int ret; ret = libc_vopenat(dirfd, path, flags, ap); if (ret != -1) { /* * There are methods for closing descriptors (libc-internal code * paths, direct syscalls) which close descriptors in ways that * we can't intercept, so try to recover when we notice that * that's happened */ swrap_remove_stale(ret); } return ret; } int openat(int dirfd, const char *path, int flags, ...) { va_list ap; int fd; va_start(ap, flags); fd = swrap_vopenat(dirfd, path, flags, ap); va_end(ap); return fd; } /**************************************************************************** * GETPEERNAME ***************************************************************************/ static int swrap_getpeername(int s, struct sockaddr *name, socklen_t *addrlen) { struct socket_info *si = find_socket_info(s); socklen_t len; int ret = -1; if (!si) { return libc_getpeername(s, name, addrlen); } SWRAP_LOCK_SI(si); if (si->peername.sa_socklen == 0) { errno = ENOTCONN; goto out; } len = MIN(*addrlen, si->peername.sa_socklen); if (len == 0) { ret = 0; goto out; } memcpy(name, &si->peername.sa.ss, len); *addrlen = si->peername.sa_socklen; ret = 0; out: SWRAP_UNLOCK_SI(si); return ret; } #ifdef HAVE_ACCEPT_PSOCKLEN_T int getpeername(int s, struct sockaddr *name, Psocklen_t addrlen) #else int getpeername(int s, struct sockaddr *name, socklen_t *addrlen) #endif { return swrap_getpeername(s, name, (socklen_t *)addrlen); } /**************************************************************************** * GETSOCKNAME ***************************************************************************/ static int swrap_getsockname(int s, struct sockaddr *name, socklen_t *addrlen) { struct socket_info *si = find_socket_info(s); socklen_t len; int ret = -1; if (!si) { return libc_getsockname(s, name, addrlen); } SWRAP_LOCK_SI(si); len = MIN(*addrlen, si->myname.sa_socklen); if (len == 0) { ret = 0; goto out; } memcpy(name, &si->myname.sa.ss, len); *addrlen = si->myname.sa_socklen; ret = 0; out: SWRAP_UNLOCK_SI(si); return ret; } #ifdef HAVE_ACCEPT_PSOCKLEN_T int getsockname(int s, struct sockaddr *name, Psocklen_t addrlen) #else int getsockname(int s, struct sockaddr *name, socklen_t *addrlen) #endif { return swrap_getsockname(s, name, (socklen_t *)addrlen); } /**************************************************************************** * GETSOCKOPT ***************************************************************************/ #ifndef SO_PROTOCOL # ifdef SO_PROTOTYPE /* The Solaris name */ # define SO_PROTOCOL SO_PROTOTYPE # endif /* SO_PROTOTYPE */ #endif /* SO_PROTOCOL */ static int swrap_getsockopt(int s, int level, int optname, void *optval, socklen_t *optlen) { struct socket_info *si = find_socket_info(s); int ret; if (!si) { return libc_getsockopt(s, level, optname, optval, optlen); } SWRAP_LOCK_SI(si); if (level == SOL_SOCKET) { switch (optname) { #ifdef SO_DOMAIN case SO_DOMAIN: if (optval == NULL || optlen == NULL || *optlen < (socklen_t)sizeof(int)) { errno = EINVAL; ret = -1; goto done; } *optlen = sizeof(int); *(int *)optval = si->family; ret = 0; goto done; #endif /* SO_DOMAIN */ #ifdef SO_PROTOCOL case SO_PROTOCOL: if (optval == NULL || optlen == NULL || *optlen < (socklen_t)sizeof(int)) { errno = EINVAL; ret = -1; goto done; } *optlen = sizeof(int); *(int *)optval = si->protocol; ret = 0; goto done; #endif /* SO_PROTOCOL */ case SO_TYPE: if (optval == NULL || optlen == NULL || *optlen < (socklen_t)sizeof(int)) { errno = EINVAL; ret = -1; goto done; } *optlen = sizeof(int); *(int *)optval = si->type; ret = 0; goto done; default: ret = libc_getsockopt(s, level, optname, optval, optlen); goto done; } } else if (level == IPPROTO_TCP) { switch (optname) { #ifdef TCP_NODELAY case TCP_NODELAY: /* * This enables sending packets directly out over TCP. * As a unix socket is doing that any way, report it as * enabled. */ if (optval == NULL || optlen == NULL || *optlen < (socklen_t)sizeof(int)) { errno = EINVAL; ret = -1; goto done; } *optlen = sizeof(int); *(int *)optval = si->tcp_nodelay; ret = 0; goto done; #endif /* TCP_NODELAY */ default: break; } } errno = ENOPROTOOPT; ret = -1; done: SWRAP_UNLOCK_SI(si); return ret; } #ifdef HAVE_ACCEPT_PSOCKLEN_T int getsockopt(int s, int level, int optname, void *optval, Psocklen_t optlen) #else int getsockopt(int s, int level, int optname, void *optval, socklen_t *optlen) #endif { return swrap_getsockopt(s, level, optname, optval, (socklen_t *)optlen); } /**************************************************************************** * SETSOCKOPT ***************************************************************************/ static int swrap_setsockopt(int s, int level, int optname, const void *optval, socklen_t optlen) { struct socket_info *si = find_socket_info(s); int ret; if (!si) { return libc_setsockopt(s, level, optname, optval, optlen); } if (level == SOL_SOCKET) { return libc_setsockopt(s, level, optname, optval, optlen); } SWRAP_LOCK_SI(si); if (level == IPPROTO_TCP) { switch (optname) { #ifdef TCP_NODELAY case TCP_NODELAY: { int i; /* * This enables sending packets directly out over TCP. * A unix socket is doing that any way. */ if (optval == NULL || optlen == 0 || optlen < (socklen_t)sizeof(int)) { errno = EINVAL; ret = -1; goto done; } i = *discard_const_p(int, optval); if (i != 0 && i != 1) { errno = EINVAL; ret = -1; goto done; } si->tcp_nodelay = i; ret = 0; goto done; } #endif /* TCP_NODELAY */ default: break; } } switch (si->family) { case AF_INET: if (level == IPPROTO_IP) { #ifdef IP_PKTINFO if (optname == IP_PKTINFO) { si->pktinfo = AF_INET; } #endif /* IP_PKTINFO */ } ret = 0; goto done; #ifdef HAVE_IPV6 case AF_INET6: if (level == IPPROTO_IPV6) { #ifdef IPV6_RECVPKTINFO if (optname == IPV6_RECVPKTINFO) { si->pktinfo = AF_INET6; } #endif /* IPV6_PKTINFO */ } ret = 0; goto done; #endif default: errno = ENOPROTOOPT; ret = -1; goto done; } done: SWRAP_UNLOCK_SI(si); return ret; } int setsockopt(int s, int level, int optname, const void *optval, socklen_t optlen) { return swrap_setsockopt(s, level, optname, optval, optlen); } /**************************************************************************** * IOCTL ***************************************************************************/ static int swrap_vioctl(int s, unsigned long int r, va_list va) { struct socket_info *si = find_socket_info(s); va_list ap; int value; int rc; if (!si) { return libc_vioctl(s, r, va); } SWRAP_LOCK_SI(si); va_copy(ap, va); rc = libc_vioctl(s, r, va); switch (r) { case FIONREAD: value = *((int *)va_arg(ap, int *)); if (rc == -1 && errno != EAGAIN && errno != ENOBUFS) { swrap_pcap_dump_packet(si, NULL, SWRAP_PENDING_RST, NULL, 0); } else if (value == 0) { /* END OF FILE */ swrap_pcap_dump_packet(si, NULL, SWRAP_PENDING_RST, NULL, 0); } break; } va_end(ap); SWRAP_UNLOCK_SI(si); return rc; } #ifdef HAVE_IOCTL_INT int ioctl(int s, int r, ...) #else int ioctl(int s, unsigned long int r, ...) #endif { va_list va; int rc; va_start(va, r); rc = swrap_vioctl(s, (unsigned long int) r, va); va_end(va); return rc; } /***************** * CMSG *****************/ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL #ifndef CMSG_ALIGN # ifdef _ALIGN /* BSD */ #define CMSG_ALIGN _ALIGN # else #define CMSG_ALIGN(len) (((len) + sizeof(size_t) - 1) & ~(sizeof(size_t) - 1)) # endif /* _ALIGN */ #endif /* CMSG_ALIGN */ /** * @brief Add a cmsghdr to a msghdr. * * This is an function to add any type of cmsghdr. It will operate on the * msg->msg_control and msg->msg_controllen you pass in by adapting them to * the buffer position after the added cmsg element. Hence, this function is * intended to be used with an intermediate msghdr and not on the original * one handed in by the client. * * @param[in] msg The msghdr to which to add the cmsg. * * @param[in] level The cmsg level to set. * * @param[in] type The cmsg type to set. * * @param[in] data The cmsg data to set. * * @param[in] len the length of the data to set. */ static void swrap_msghdr_add_cmsghdr(struct msghdr *msg, int level, int type, const void *data, size_t len) { size_t cmlen = CMSG_LEN(len); size_t cmspace = CMSG_SPACE(len); uint8_t cmbuf[cmspace]; void *cast_ptr = (void *)cmbuf; struct cmsghdr *cm = (struct cmsghdr *)cast_ptr; uint8_t *p; memset(cmbuf, 0, cmspace); if (msg->msg_controllen < cmlen) { cmlen = msg->msg_controllen; msg->msg_flags |= MSG_CTRUNC; } if (msg->msg_controllen < cmspace) { cmspace = msg->msg_controllen; } /* * We copy the full input data into an intermediate cmsghdr first * in order to more easily cope with truncation. */ cm->cmsg_len = cmlen; cm->cmsg_level = level; cm->cmsg_type = type; memcpy(CMSG_DATA(cm), data, len); /* * We now copy the possibly truncated buffer. * We copy cmlen bytes, but consume cmspace bytes, * leaving the possible padding uninitialiazed. */ p = (uint8_t *)msg->msg_control; memcpy(p, cm, cmlen); p += cmspace; msg->msg_control = p; msg->msg_controllen -= cmspace; return; } static int swrap_msghdr_add_pktinfo(struct socket_info *si, struct msghdr *msg) { /* Add packet info */ switch (si->pktinfo) { #if defined(IP_PKTINFO) && (defined(HAVE_STRUCT_IN_PKTINFO) || defined(IP_RECVDSTADDR)) case AF_INET: { struct sockaddr_in *sin; #if defined(HAVE_STRUCT_IN_PKTINFO) struct in_pktinfo pkt; #elif defined(IP_RECVDSTADDR) struct in_addr pkt; #endif if (si->bindname.sa_socklen == sizeof(struct sockaddr_in)) { sin = &si->bindname.sa.in; } else { if (si->myname.sa_socklen != sizeof(struct sockaddr_in)) { return 0; } sin = &si->myname.sa.in; } ZERO_STRUCT(pkt); #if defined(HAVE_STRUCT_IN_PKTINFO) pkt.ipi_ifindex = socket_wrapper_default_iface(); pkt.ipi_addr.s_addr = sin->sin_addr.s_addr; #elif defined(IP_RECVDSTADDR) pkt = sin->sin_addr; #endif swrap_msghdr_add_cmsghdr(msg, IPPROTO_IP, IP_PKTINFO, &pkt, sizeof(pkt)); break; } #endif /* IP_PKTINFO */ #if defined(HAVE_IPV6) case AF_INET6: { #if defined(IPV6_PKTINFO) && defined(HAVE_STRUCT_IN6_PKTINFO) struct sockaddr_in6 *sin6; struct in6_pktinfo pkt6; if (si->bindname.sa_socklen == sizeof(struct sockaddr_in6)) { sin6 = &si->bindname.sa.in6; } else { if (si->myname.sa_socklen != sizeof(struct sockaddr_in6)) { return 0; } sin6 = &si->myname.sa.in6; } ZERO_STRUCT(pkt6); pkt6.ipi6_ifindex = socket_wrapper_default_iface(); pkt6.ipi6_addr = sin6->sin6_addr; swrap_msghdr_add_cmsghdr(msg, IPPROTO_IPV6, IPV6_PKTINFO, &pkt6, sizeof(pkt6)); #endif /* HAVE_STRUCT_IN6_PKTINFO */ break; } #endif /* IPV6_PKTINFO */ default: return -1; } return 0; } static int swrap_msghdr_add_socket_info(struct socket_info *si, struct msghdr *omsg) { int rc = 0; if (si->pktinfo > 0) { rc = swrap_msghdr_add_pktinfo(si, omsg); } return rc; } static int swrap_sendmsg_copy_cmsg(struct cmsghdr *cmsg, uint8_t **cm_data, size_t *cm_data_space); static int swrap_sendmsg_filter_cmsg_socket(struct cmsghdr *cmsg, uint8_t **cm_data, size_t *cm_data_space); static int swrap_sendmsg_filter_cmsghdr(struct msghdr *msg, uint8_t **cm_data, size_t *cm_data_space) { struct cmsghdr *cmsg; int rc = -1; /* Nothing to do */ if (msg->msg_controllen == 0 || msg->msg_control == NULL) { return 0; } for (cmsg = CMSG_FIRSTHDR(msg); cmsg != NULL; cmsg = CMSG_NXTHDR(msg, cmsg)) { switch (cmsg->cmsg_level) { case IPPROTO_IP: rc = swrap_sendmsg_filter_cmsg_socket(cmsg, cm_data, cm_data_space); break; default: rc = swrap_sendmsg_copy_cmsg(cmsg, cm_data, cm_data_space); break; } } return rc; } static int swrap_sendmsg_copy_cmsg(struct cmsghdr *cmsg, uint8_t **cm_data, size_t *cm_data_space) { size_t cmspace; uint8_t *p; cmspace = *cm_data_space + CMSG_ALIGN(cmsg->cmsg_len); p = realloc((*cm_data), cmspace); if (p == NULL) { return -1; } (*cm_data) = p; p = (*cm_data) + (*cm_data_space); *cm_data_space = cmspace; memcpy(p, cmsg, cmsg->cmsg_len); return 0; } static int swrap_sendmsg_filter_cmsg_pktinfo(struct cmsghdr *cmsg, uint8_t **cm_data, size_t *cm_data_space); static int swrap_sendmsg_filter_cmsg_socket(struct cmsghdr *cmsg, uint8_t **cm_data, size_t *cm_data_space) { int rc = -1; switch(cmsg->cmsg_type) { #ifdef IP_PKTINFO case IP_PKTINFO: rc = swrap_sendmsg_filter_cmsg_pktinfo(cmsg, cm_data, cm_data_space); break; #endif #ifdef IPV6_PKTINFO case IPV6_PKTINFO: rc = swrap_sendmsg_filter_cmsg_pktinfo(cmsg, cm_data, cm_data_space); break; #endif default: break; } return rc; } static int swrap_sendmsg_filter_cmsg_pktinfo(struct cmsghdr *cmsg, uint8_t **cm_data, size_t *cm_data_space) { (void)cmsg; /* unused */ (void)cm_data; /* unused */ (void)cm_data_space; /* unused */ /* * Passing a IP pktinfo to a unix socket might be rejected by the * Kernel, at least on FreeBSD. So skip this cmsg. */ return 0; } #endif /* HAVE_STRUCT_MSGHDR_MSG_CONTROL */ static ssize_t swrap_sendmsg_before(int fd, struct socket_info *si, struct msghdr *msg, struct iovec *tmp_iov, struct sockaddr_un *tmp_un, const struct sockaddr_un **to_un, const struct sockaddr **to, int *bcast) { size_t i, len = 0; ssize_t ret = -1; if (to_un) { *to_un = NULL; } if (to) { *to = NULL; } if (bcast) { *bcast = 0; } SWRAP_LOCK_SI(si); switch (si->type) { case SOCK_STREAM: { unsigned long mtu; if (!si->connected) { errno = ENOTCONN; goto out; } if (msg->msg_iovlen == 0) { break; } mtu = socket_wrapper_mtu(); for (i = 0; i < (size_t)msg->msg_iovlen; i++) { size_t nlen; nlen = len + msg->msg_iov[i].iov_len; if (nlen < len) { /* overflow */ errno = EMSGSIZE; goto out; } if (nlen > mtu) { break; } } msg->msg_iovlen = i; if (msg->msg_iovlen == 0) { *tmp_iov = msg->msg_iov[0]; tmp_iov->iov_len = MIN((size_t)tmp_iov->iov_len, (size_t)mtu); msg->msg_iov = tmp_iov; msg->msg_iovlen = 1; } break; } case SOCK_DGRAM: if (si->connected) { if (msg->msg_name != NULL) { /* * We are dealing with unix sockets and if we * are connected, we should only talk to the * connected unix path. Using the fd to send * to another server would be hard to achieve. */ msg->msg_name = NULL; msg->msg_namelen = 0; } } else { const struct sockaddr *msg_name; msg_name = (const struct sockaddr *)msg->msg_name; if (msg_name == NULL) { errno = ENOTCONN; goto out; } ret = sockaddr_convert_to_un(si, msg_name, msg->msg_namelen, tmp_un, 0, bcast); if (ret == -1) { goto out; } if (to_un) { *to_un = tmp_un; } if (to) { *to = msg_name; } msg->msg_name = tmp_un; msg->msg_namelen = sizeof(*tmp_un); } if (si->bound == 0) { ret = swrap_auto_bind(fd, si, si->family); if (ret == -1) { SWRAP_UNLOCK_SI(si); if (errno == ENOTSOCK) { swrap_remove_stale(fd); ret = -ENOTSOCK; } else { SWRAP_LOG(SWRAP_LOG_ERROR, "swrap_sendmsg_before failed"); } return ret; } } if (!si->defer_connect) { break; } ret = sockaddr_convert_to_un(si, &si->peername.sa.s, si->peername.sa_socklen, tmp_un, 0, NULL); if (ret == -1) { goto out; } ret = libc_connect(fd, (struct sockaddr *)(void *)tmp_un, sizeof(*tmp_un)); /* to give better errors */ if (ret == -1 && errno == ENOENT) { errno = EHOSTUNREACH; } if (ret == -1) { goto out; } si->defer_connect = 0; break; default: errno = EHOSTUNREACH; goto out; } #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL if (msg->msg_controllen > 0 && msg->msg_control != NULL) { uint8_t *cmbuf = NULL; size_t cmlen = 0; ret = swrap_sendmsg_filter_cmsghdr(msg, &cmbuf, &cmlen); if (ret < 0) { free(cmbuf); goto out; } if (cmlen == 0) { msg->msg_controllen = 0; msg->msg_control = NULL; } else if (cmlen < msg->msg_controllen && cmbuf != NULL) { memcpy(msg->msg_control, cmbuf, cmlen); msg->msg_controllen = cmlen; } free(cmbuf); } #endif ret = 0; out: SWRAP_UNLOCK_SI(si); return ret; } static void swrap_sendmsg_after(int fd, struct socket_info *si, struct msghdr *msg, const struct sockaddr *to, ssize_t ret) { int saved_errno = errno; size_t i, len = 0; uint8_t *buf; off_t ofs = 0; size_t avail = 0; size_t remain; /* to give better errors */ if (ret == -1) { if (saved_errno == ENOENT) { saved_errno = EHOSTUNREACH; } else if (saved_errno == ENOTSOCK) { /* If the fd is not a socket, remove it */ swrap_remove_stale(fd); } } for (i = 0; i < (size_t)msg->msg_iovlen; i++) { avail += msg->msg_iov[i].iov_len; } if (ret == -1) { remain = MIN(80, avail); } else { remain = ret; } /* we capture it as one single packet */ buf = (uint8_t *)malloc(remain); if (!buf) { /* we just not capture the packet */ errno = saved_errno; return; } for (i = 0; i < (size_t)msg->msg_iovlen; i++) { size_t this_time = MIN(remain, (size_t)msg->msg_iov[i].iov_len); memcpy(buf + ofs, msg->msg_iov[i].iov_base, this_time); ofs += this_time; remain -= this_time; } len = ofs; SWRAP_LOCK_SI(si); switch (si->type) { case SOCK_STREAM: if (ret == -1) { swrap_pcap_dump_packet(si, NULL, SWRAP_SEND, buf, len); swrap_pcap_dump_packet(si, NULL, SWRAP_SEND_RST, NULL, 0); } else { swrap_pcap_dump_packet(si, NULL, SWRAP_SEND, buf, len); } break; case SOCK_DGRAM: if (si->connected) { to = &si->peername.sa.s; } if (ret == -1) { swrap_pcap_dump_packet(si, to, SWRAP_SENDTO, buf, len); swrap_pcap_dump_packet(si, to, SWRAP_SENDTO_UNREACH, buf, len); } else { swrap_pcap_dump_packet(si, to, SWRAP_SENDTO, buf, len); } break; } SWRAP_UNLOCK_SI(si); free(buf); errno = saved_errno; } static int swrap_recvmsg_before(int fd, struct socket_info *si, struct msghdr *msg, struct iovec *tmp_iov) { size_t i, len = 0; int ret = -1; SWRAP_LOCK_SI(si); (void)fd; /* unused */ switch (si->type) { case SOCK_STREAM: { unsigned int mtu; if (!si->connected) { errno = ENOTCONN; goto out; } if (msg->msg_iovlen == 0) { break; } mtu = socket_wrapper_mtu(); for (i = 0; i < (size_t)msg->msg_iovlen; i++) { size_t nlen; nlen = len + msg->msg_iov[i].iov_len; if (nlen > mtu) { break; } } msg->msg_iovlen = i; if (msg->msg_iovlen == 0) { *tmp_iov = msg->msg_iov[0]; tmp_iov->iov_len = MIN((size_t)tmp_iov->iov_len, (size_t)mtu); msg->msg_iov = tmp_iov; msg->msg_iovlen = 1; } break; } case SOCK_DGRAM: if (msg->msg_name == NULL) { errno = EINVAL; goto out; } if (msg->msg_iovlen == 0) { break; } if (si->bound == 0) { ret = swrap_auto_bind(fd, si, si->family); if (ret == -1) { SWRAP_UNLOCK_SI(si); /* * When attempting to read or write to a * descriptor, if an underlying autobind fails * because it's not a socket, stop intercepting * uses of that descriptor. */ if (errno == ENOTSOCK) { swrap_remove_stale(fd); ret = -ENOTSOCK; } else { SWRAP_LOG(SWRAP_LOG_ERROR, "swrap_recvmsg_before failed"); } return ret; } } break; default: errno = EHOSTUNREACH; goto out; } ret = 0; out: SWRAP_UNLOCK_SI(si); return ret; } static int swrap_recvmsg_after(int fd, struct socket_info *si, struct msghdr *msg, const struct sockaddr_un *un_addr, socklen_t un_addrlen, ssize_t ret) { int saved_errno = errno; size_t i; uint8_t *buf = NULL; off_t ofs = 0; size_t avail = 0; size_t remain; int rc; /* to give better errors */ if (ret == -1) { if (saved_errno == ENOENT) { saved_errno = EHOSTUNREACH; } else if (saved_errno == ENOTSOCK) { /* If the fd is not a socket, remove it */ swrap_remove_stale(fd); } } for (i = 0; i < (size_t)msg->msg_iovlen; i++) { avail += msg->msg_iov[i].iov_len; } SWRAP_LOCK_SI(si); /* Convert the socket address before we leave */ if (si->type == SOCK_DGRAM && un_addr != NULL) { rc = sockaddr_convert_from_un(si, un_addr, un_addrlen, si->family, msg->msg_name, &msg->msg_namelen); if (rc == -1) { goto done; } } if (avail == 0) { rc = 0; goto done; } if (ret == -1) { remain = MIN(80, avail); } else { remain = ret; } /* we capture it as one single packet */ buf = (uint8_t *)malloc(remain); if (buf == NULL) { /* we just not capture the packet */ SWRAP_UNLOCK_SI(si); errno = saved_errno; return -1; } for (i = 0; i < (size_t)msg->msg_iovlen; i++) { size_t this_time = MIN(remain, (size_t)msg->msg_iov[i].iov_len); memcpy(buf + ofs, msg->msg_iov[i].iov_base, this_time); ofs += this_time; remain -= this_time; } switch (si->type) { case SOCK_STREAM: if (ret == -1 && saved_errno != EAGAIN && saved_errno != ENOBUFS) { swrap_pcap_dump_packet(si, NULL, SWRAP_RECV_RST, NULL, 0); } else if (ret == 0) { /* END OF FILE */ swrap_pcap_dump_packet(si, NULL, SWRAP_RECV_RST, NULL, 0); } else if (ret > 0) { swrap_pcap_dump_packet(si, NULL, SWRAP_RECV, buf, ret); } break; case SOCK_DGRAM: if (ret == -1) { break; } if (un_addr != NULL) { swrap_pcap_dump_packet(si, msg->msg_name, SWRAP_RECVFROM, buf, ret); } else { swrap_pcap_dump_packet(si, msg->msg_name, SWRAP_RECV, buf, ret); } break; } rc = 0; done: free(buf); errno = saved_errno; #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL if (rc == 0 && msg->msg_controllen > 0 && msg->msg_control != NULL) { rc = swrap_msghdr_add_socket_info(si, msg); if (rc < 0) { SWRAP_UNLOCK_SI(si); return -1; } } #endif SWRAP_UNLOCK_SI(si); return rc; } /**************************************************************************** * RECVFROM ***************************************************************************/ static ssize_t swrap_recvfrom(int s, void *buf, size_t len, int flags, struct sockaddr *from, socklen_t *fromlen) { struct swrap_address from_addr = { .sa_socklen = sizeof(struct sockaddr_un), }; ssize_t ret; struct socket_info *si = find_socket_info(s); struct swrap_address saddr = { .sa_socklen = sizeof(struct sockaddr_storage), }; struct msghdr msg; struct iovec tmp; int tret; if (!si) { return libc_recvfrom(s, buf, len, flags, from, fromlen); } tmp.iov_base = buf; tmp.iov_len = len; ZERO_STRUCT(msg); if (from != NULL && fromlen != NULL) { msg.msg_name = from; /* optional address */ msg.msg_namelen = *fromlen; /* size of address */ } else { msg.msg_name = &saddr.sa.s; /* optional address */ msg.msg_namelen = saddr.sa_socklen; /* size of address */ } msg.msg_iov = &tmp; /* scatter/gather array */ msg.msg_iovlen = 1; /* # elements in msg_iov */ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg.msg_control = NULL; /* ancillary data, see below */ msg.msg_controllen = 0; /* ancillary data buffer len */ msg.msg_flags = 0; /* flags on received message */ #endif tret = swrap_recvmsg_before(s, si, &msg, &tmp); if (tret < 0) { return -1; } buf = msg.msg_iov[0].iov_base; len = msg.msg_iov[0].iov_len; ret = libc_recvfrom(s, buf, len, flags, &from_addr.sa.s, &from_addr.sa_socklen); if (ret == -1) { return ret; } tret = swrap_recvmsg_after(s, si, &msg, &from_addr.sa.un, from_addr.sa_socklen, ret); if (tret != 0) { return tret; } if (from != NULL && fromlen != NULL) { *fromlen = msg.msg_namelen; } return ret; } #ifdef HAVE_ACCEPT_PSOCKLEN_T ssize_t recvfrom(int s, void *buf, size_t len, int flags, struct sockaddr *from, Psocklen_t fromlen) #else ssize_t recvfrom(int s, void *buf, size_t len, int flags, struct sockaddr *from, socklen_t *fromlen) #endif { return swrap_recvfrom(s, buf, len, flags, from, (socklen_t *)fromlen); } /**************************************************************************** * SENDTO ***************************************************************************/ static ssize_t swrap_sendto(int s, const void *buf, size_t len, int flags, const struct sockaddr *to, socklen_t tolen) { struct msghdr msg; struct iovec tmp; struct swrap_address un_addr = { .sa_socklen = sizeof(struct sockaddr_un), }; const struct sockaddr_un *to_un = NULL; ssize_t ret; int rc; struct socket_info *si = find_socket_info(s); int bcast = 0; if (!si) { return libc_sendto(s, buf, len, flags, to, tolen); } tmp.iov_base = discard_const_p(char, buf); tmp.iov_len = len; ZERO_STRUCT(msg); msg.msg_name = discard_const_p(struct sockaddr, to); /* optional address */ msg.msg_namelen = tolen; /* size of address */ msg.msg_iov = &tmp; /* scatter/gather array */ msg.msg_iovlen = 1; /* # elements in msg_iov */ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg.msg_control = NULL; /* ancillary data, see below */ msg.msg_controllen = 0; /* ancillary data buffer len */ msg.msg_flags = 0; /* flags on received message */ #endif rc = swrap_sendmsg_before(s, si, &msg, &tmp, &un_addr.sa.un, &to_un, &to, &bcast); if (rc < 0) { return -1; } buf = msg.msg_iov[0].iov_base; len = msg.msg_iov[0].iov_len; if (bcast) { struct stat st; unsigned int iface; unsigned int prt = ntohs(((const struct sockaddr_in *)(const void *)to)->sin_port); char type; char *swrap_dir = NULL; type = SOCKET_TYPE_CHAR_UDP; swrap_dir = socket_wrapper_dir(); if (swrap_dir == NULL) { return -1; } for(iface=0; iface <= MAX_WRAPPED_INTERFACES; iface++) { snprintf(un_addr.sa.un.sun_path, sizeof(un_addr.sa.un.sun_path), "%s/"SOCKET_FORMAT, swrap_dir, type, iface, prt); if (stat(un_addr.sa.un.sun_path, &st) != 0) continue; /* ignore the any errors in broadcast sends */ libc_sendto(s, buf, len, flags, &un_addr.sa.s, un_addr.sa_socklen); } SAFE_FREE(swrap_dir); SWRAP_LOCK_SI(si); swrap_pcap_dump_packet(si, to, SWRAP_SENDTO, buf, len); SWRAP_UNLOCK_SI(si); return len; } SWRAP_LOCK_SI(si); /* * If it is a dgram socket and we are connected, don't include the * 'to' address. */ if (si->type == SOCK_DGRAM && si->connected) { ret = libc_sendto(s, buf, len, flags, NULL, 0); } else { ret = libc_sendto(s, buf, len, flags, (struct sockaddr *)msg.msg_name, msg.msg_namelen); } SWRAP_UNLOCK_SI(si); swrap_sendmsg_after(s, si, &msg, to, ret); return ret; } ssize_t sendto(int s, const void *buf, size_t len, int flags, const struct sockaddr *to, socklen_t tolen) { return swrap_sendto(s, buf, len, flags, to, tolen); } /**************************************************************************** * READV ***************************************************************************/ static ssize_t swrap_recv(int s, void *buf, size_t len, int flags) { struct socket_info *si; struct msghdr msg; struct swrap_address saddr = { .sa_socklen = sizeof(struct sockaddr_storage), }; struct iovec tmp; ssize_t ret; int tret; si = find_socket_info(s); if (si == NULL) { return libc_recv(s, buf, len, flags); } tmp.iov_base = buf; tmp.iov_len = len; ZERO_STRUCT(msg); msg.msg_name = &saddr.sa.s; /* optional address */ msg.msg_namelen = saddr.sa_socklen; /* size of address */ msg.msg_iov = &tmp; /* scatter/gather array */ msg.msg_iovlen = 1; /* # elements in msg_iov */ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg.msg_control = NULL; /* ancillary data, see below */ msg.msg_controllen = 0; /* ancillary data buffer len */ msg.msg_flags = 0; /* flags on received message */ #endif tret = swrap_recvmsg_before(s, si, &msg, &tmp); if (tret < 0) { return -1; } buf = msg.msg_iov[0].iov_base; len = msg.msg_iov[0].iov_len; ret = libc_recv(s, buf, len, flags); tret = swrap_recvmsg_after(s, si, &msg, NULL, 0, ret); if (tret != 0) { return tret; } return ret; } ssize_t recv(int s, void *buf, size_t len, int flags) { return swrap_recv(s, buf, len, flags); } /**************************************************************************** * READ ***************************************************************************/ static ssize_t swrap_read(int s, void *buf, size_t len) { struct socket_info *si; struct msghdr msg; struct iovec tmp; struct swrap_address saddr = { .sa_socklen = sizeof(struct sockaddr_storage), }; ssize_t ret; int tret; si = find_socket_info(s); if (si == NULL) { return libc_read(s, buf, len); } tmp.iov_base = buf; tmp.iov_len = len; ZERO_STRUCT(msg); msg.msg_name = &saddr.sa.ss; /* optional address */ msg.msg_namelen = saddr.sa_socklen; /* size of address */ msg.msg_iov = &tmp; /* scatter/gather array */ msg.msg_iovlen = 1; /* # elements in msg_iov */ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg.msg_control = NULL; /* ancillary data, see below */ msg.msg_controllen = 0; /* ancillary data buffer len */ msg.msg_flags = 0; /* flags on received message */ #endif tret = swrap_recvmsg_before(s, si, &msg, &tmp); if (tret < 0) { if (tret == -ENOTSOCK) { return libc_read(s, buf, len); } return -1; } buf = msg.msg_iov[0].iov_base; len = msg.msg_iov[0].iov_len; ret = libc_read(s, buf, len); tret = swrap_recvmsg_after(s, si, &msg, NULL, 0, ret); if (tret != 0) { return tret; } return ret; } ssize_t read(int s, void *buf, size_t len) { return swrap_read(s, buf, len); } /**************************************************************************** * WRITE ***************************************************************************/ static ssize_t swrap_write(int s, const void *buf, size_t len) { struct msghdr msg; struct iovec tmp; struct sockaddr_un un_addr; ssize_t ret; int rc; struct socket_info *si; si = find_socket_info(s); if (si == NULL) { return libc_write(s, buf, len); } tmp.iov_base = discard_const_p(char, buf); tmp.iov_len = len; ZERO_STRUCT(msg); msg.msg_name = NULL; /* optional address */ msg.msg_namelen = 0; /* size of address */ msg.msg_iov = &tmp; /* scatter/gather array */ msg.msg_iovlen = 1; /* # elements in msg_iov */ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg.msg_control = NULL; /* ancillary data, see below */ msg.msg_controllen = 0; /* ancillary data buffer len */ msg.msg_flags = 0; /* flags on received message */ #endif rc = swrap_sendmsg_before(s, si, &msg, &tmp, &un_addr, NULL, NULL, NULL); if (rc < 0) { return -1; } buf = msg.msg_iov[0].iov_base; len = msg.msg_iov[0].iov_len; ret = libc_write(s, buf, len); swrap_sendmsg_after(s, si, &msg, NULL, ret); return ret; } ssize_t write(int s, const void *buf, size_t len) { return swrap_write(s, buf, len); } /**************************************************************************** * SEND ***************************************************************************/ static ssize_t swrap_send(int s, const void *buf, size_t len, int flags) { struct msghdr msg; struct iovec tmp; struct sockaddr_un un_addr; ssize_t ret; int rc; struct socket_info *si = find_socket_info(s); if (!si) { return libc_send(s, buf, len, flags); } tmp.iov_base = discard_const_p(char, buf); tmp.iov_len = len; ZERO_STRUCT(msg); msg.msg_name = NULL; /* optional address */ msg.msg_namelen = 0; /* size of address */ msg.msg_iov = &tmp; /* scatter/gather array */ msg.msg_iovlen = 1; /* # elements in msg_iov */ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg.msg_control = NULL; /* ancillary data, see below */ msg.msg_controllen = 0; /* ancillary data buffer len */ msg.msg_flags = 0; /* flags on received message */ #endif rc = swrap_sendmsg_before(s, si, &msg, &tmp, &un_addr, NULL, NULL, NULL); if (rc < 0) { return -1; } buf = msg.msg_iov[0].iov_base; len = msg.msg_iov[0].iov_len; ret = libc_send(s, buf, len, flags); swrap_sendmsg_after(s, si, &msg, NULL, ret); return ret; } ssize_t send(int s, const void *buf, size_t len, int flags) { return swrap_send(s, buf, len, flags); } /**************************************************************************** * RECVMSG ***************************************************************************/ static ssize_t swrap_recvmsg(int s, struct msghdr *omsg, int flags) { struct swrap_address from_addr = { .sa_socklen = sizeof(struct sockaddr_un), }; struct swrap_address convert_addr = { .sa_socklen = sizeof(struct sockaddr_storage), }; struct socket_info *si; struct msghdr msg; struct iovec tmp; #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL size_t msg_ctrllen_filled; size_t msg_ctrllen_left; #endif ssize_t ret; int rc; si = find_socket_info(s); if (si == NULL) { return libc_recvmsg(s, omsg, flags); } tmp.iov_base = NULL; tmp.iov_len = 0; ZERO_STRUCT(msg); msg.msg_name = &from_addr.sa; /* optional address */ msg.msg_namelen = from_addr.sa_socklen; /* size of address */ msg.msg_iov = omsg->msg_iov; /* scatter/gather array */ msg.msg_iovlen = omsg->msg_iovlen; /* # elements in msg_iov */ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg_ctrllen_filled = 0; msg_ctrllen_left = omsg->msg_controllen; msg.msg_control = omsg->msg_control; /* ancillary data, see below */ msg.msg_controllen = omsg->msg_controllen; /* ancillary data buffer len */ msg.msg_flags = omsg->msg_flags; /* flags on received message */ #endif rc = swrap_recvmsg_before(s, si, &msg, &tmp); if (rc < 0) { return -1; } ret = libc_recvmsg(s, &msg, flags); #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg_ctrllen_filled += msg.msg_controllen; msg_ctrllen_left -= msg.msg_controllen; if (omsg->msg_control != NULL) { uint8_t *p; p = omsg->msg_control; p += msg_ctrllen_filled; msg.msg_control = p; msg.msg_controllen = msg_ctrllen_left; } else { msg.msg_control = NULL; msg.msg_controllen = 0; } #endif /* * We convert the unix address to a IP address so we need a buffer * which can store the address in case of SOCK_DGRAM, see below. */ msg.msg_name = &convert_addr.sa; msg.msg_namelen = convert_addr.sa_socklen; rc = swrap_recvmsg_after(s, si, &msg, &from_addr.sa.un, from_addr.sa_socklen, ret); if (rc != 0) { return rc; } #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL if (omsg->msg_control != NULL) { /* msg.msg_controllen = space left */ msg_ctrllen_left = msg.msg_controllen; msg_ctrllen_filled = omsg->msg_controllen - msg_ctrllen_left; } /* Update the original message length */ omsg->msg_controllen = msg_ctrllen_filled; omsg->msg_flags = msg.msg_flags; #endif omsg->msg_iovlen = msg.msg_iovlen; SWRAP_LOCK_SI(si); /* * From the manpage: * * The msg_name field points to a caller-allocated buffer that is * used to return the source address if the socket is unconnected. The * caller should set msg_namelen to the size of this buffer before this * call; upon return from a successful call, msg_name will contain the * length of the returned address. If the application does not need * to know the source address, msg_name can be specified as NULL. */ if (si->type == SOCK_STREAM) { omsg->msg_namelen = 0; } else if (omsg->msg_name != NULL && omsg->msg_namelen != 0 && omsg->msg_namelen >= msg.msg_namelen) { memcpy(omsg->msg_name, msg.msg_name, msg.msg_namelen); omsg->msg_namelen = msg.msg_namelen; } SWRAP_UNLOCK_SI(si); return ret; } ssize_t recvmsg(int sockfd, struct msghdr *msg, int flags) { return swrap_recvmsg(sockfd, msg, flags); } /**************************************************************************** * SENDMSG ***************************************************************************/ static ssize_t swrap_sendmsg(int s, const struct msghdr *omsg, int flags) { struct msghdr msg; struct iovec tmp; struct sockaddr_un un_addr; const struct sockaddr_un *to_un = NULL; const struct sockaddr *to = NULL; ssize_t ret; int rc; struct socket_info *si = find_socket_info(s); int bcast = 0; if (!si) { return libc_sendmsg(s, omsg, flags); } ZERO_STRUCT(un_addr); tmp.iov_base = NULL; tmp.iov_len = 0; ZERO_STRUCT(msg); SWRAP_LOCK_SI(si); if (si->connected == 0) { msg.msg_name = omsg->msg_name; /* optional address */ msg.msg_namelen = omsg->msg_namelen; /* size of address */ } msg.msg_iov = omsg->msg_iov; /* scatter/gather array */ msg.msg_iovlen = omsg->msg_iovlen; /* # elements in msg_iov */ SWRAP_UNLOCK_SI(si); #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL if (msg.msg_controllen > 0 && msg.msg_control != NULL) { /* omsg is a const so use a local buffer for modifications */ uint8_t cmbuf[omsg->msg_controllen]; memcpy(cmbuf, omsg->msg_control, omsg->msg_controllen); msg.msg_control = cmbuf; /* ancillary data, see below */ msg.msg_controllen = omsg->msg_controllen; /* ancillary data buffer len */ } msg.msg_flags = omsg->msg_flags; /* flags on received message */ #endif rc = swrap_sendmsg_before(s, si, &msg, &tmp, &un_addr, &to_un, &to, &bcast); if (rc < 0) { return -1; } if (bcast) { struct stat st; unsigned int iface; unsigned int prt = ntohs(((const struct sockaddr_in *)(const void *)to)->sin_port); char type; size_t i, len = 0; uint8_t *buf; off_t ofs = 0; size_t avail = 0; size_t remain; char *swrap_dir = NULL; for (i = 0; i < (size_t)msg.msg_iovlen; i++) { avail += msg.msg_iov[i].iov_len; } len = avail; remain = avail; /* we capture it as one single packet */ buf = (uint8_t *)malloc(remain); if (!buf) { return -1; } for (i = 0; i < (size_t)msg.msg_iovlen; i++) { size_t this_time = MIN(remain, (size_t)msg.msg_iov[i].iov_len); memcpy(buf + ofs, msg.msg_iov[i].iov_base, this_time); ofs += this_time; remain -= this_time; } type = SOCKET_TYPE_CHAR_UDP; swrap_dir = socket_wrapper_dir(); if (swrap_dir == NULL) { return -1; } for(iface=0; iface <= MAX_WRAPPED_INTERFACES; iface++) { snprintf(un_addr.sun_path, sizeof(un_addr.sun_path), "%s/"SOCKET_FORMAT, swrap_dir, type, iface, prt); if (stat(un_addr.sun_path, &st) != 0) continue; msg.msg_name = &un_addr; /* optional address */ msg.msg_namelen = sizeof(un_addr); /* size of address */ /* ignore the any errors in broadcast sends */ libc_sendmsg(s, &msg, flags); } SAFE_FREE(swrap_dir); SWRAP_LOCK_SI(si); swrap_pcap_dump_packet(si, to, SWRAP_SENDTO, buf, len); free(buf); SWRAP_UNLOCK_SI(si); return len; } ret = libc_sendmsg(s, &msg, flags); swrap_sendmsg_after(s, si, &msg, to, ret); return ret; } ssize_t sendmsg(int s, const struct msghdr *omsg, int flags) { return swrap_sendmsg(s, omsg, flags); } /**************************************************************************** * READV ***************************************************************************/ static ssize_t swrap_readv(int s, const struct iovec *vector, int count) { struct socket_info *si; struct msghdr msg; struct iovec tmp; struct swrap_address saddr = { .sa_socklen = sizeof(struct sockaddr_storage) }; ssize_t ret; int rc; si = find_socket_info(s); if (si == NULL) { return libc_readv(s, vector, count); } tmp.iov_base = NULL; tmp.iov_len = 0; ZERO_STRUCT(msg); msg.msg_name = &saddr.sa.s; /* optional address */ msg.msg_namelen = saddr.sa_socklen; /* size of address */ msg.msg_iov = discard_const_p(struct iovec, vector); /* scatter/gather array */ msg.msg_iovlen = count; /* # elements in msg_iov */ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg.msg_control = NULL; /* ancillary data, see below */ msg.msg_controllen = 0; /* ancillary data buffer len */ msg.msg_flags = 0; /* flags on received message */ #endif rc = swrap_recvmsg_before(s, si, &msg, &tmp); if (rc < 0) { if (rc == -ENOTSOCK) { return libc_readv(s, vector, count); } return -1; } ret = libc_readv(s, msg.msg_iov, msg.msg_iovlen); rc = swrap_recvmsg_after(s, si, &msg, NULL, 0, ret); if (rc != 0) { return rc; } return ret; } ssize_t readv(int s, const struct iovec *vector, int count) { return swrap_readv(s, vector, count); } /**************************************************************************** * WRITEV ***************************************************************************/ static ssize_t swrap_writev(int s, const struct iovec *vector, int count) { struct msghdr msg; struct iovec tmp; struct sockaddr_un un_addr; ssize_t ret; int rc; struct socket_info *si = find_socket_info(s); if (!si) { return libc_writev(s, vector, count); } tmp.iov_base = NULL; tmp.iov_len = 0; ZERO_STRUCT(msg); msg.msg_name = NULL; /* optional address */ msg.msg_namelen = 0; /* size of address */ msg.msg_iov = discard_const_p(struct iovec, vector); /* scatter/gather array */ msg.msg_iovlen = count; /* # elements in msg_iov */ #ifdef HAVE_STRUCT_MSGHDR_MSG_CONTROL msg.msg_control = NULL; /* ancillary data, see below */ msg.msg_controllen = 0; /* ancillary data buffer len */ msg.msg_flags = 0; /* flags on received message */ #endif rc = swrap_sendmsg_before(s, si, &msg, &tmp, &un_addr, NULL, NULL, NULL); if (rc < 0) { if (rc == -ENOTSOCK) { return libc_readv(s, vector, count); } return -1; } ret = libc_writev(s, msg.msg_iov, msg.msg_iovlen); swrap_sendmsg_after(s, si, &msg, NULL, ret); return ret; } ssize_t writev(int s, const struct iovec *vector, int count) { return swrap_writev(s, vector, count); } /**************************** * CLOSE ***************************/ static int swrap_close(int fd) { struct socket_info *si = NULL; int si_index; int ret; swrap_mutex_lock(&socket_reset_mutex); si_index = find_socket_info_index(fd); if (si_index == -1) { swrap_mutex_unlock(&socket_reset_mutex); return libc_close(fd); } reset_socket_info_index(fd); si = swrap_get_socket_info(si_index); swrap_mutex_lock(&first_free_mutex); SWRAP_LOCK_SI(si); ret = libc_close(fd); swrap_dec_refcount(si); if (swrap_get_refcount(si) > 0) { /* there are still references left */ goto out; } if (si->myname.sa_socklen > 0 && si->peername.sa_socklen > 0) { swrap_pcap_dump_packet(si, NULL, SWRAP_CLOSE_SEND, NULL, 0); } if (si->myname.sa_socklen > 0 && si->peername.sa_socklen > 0) { swrap_pcap_dump_packet(si, NULL, SWRAP_CLOSE_RECV, NULL, 0); swrap_pcap_dump_packet(si, NULL, SWRAP_CLOSE_ACK, NULL, 0); } if (si->un_addr.sun_path[0] != '\0') { unlink(si->un_addr.sun_path); } swrap_set_next_free(si, first_free); first_free = si_index; out: SWRAP_UNLOCK_SI(si); swrap_mutex_unlock(&first_free_mutex); swrap_mutex_unlock(&socket_reset_mutex); return ret; } int close(int fd) { return swrap_close(fd); } /**************************** * DUP ***************************/ static int swrap_dup(int fd) { struct socket_info *si; int dup_fd, idx; idx = find_socket_info_index(fd); if (idx == -1) { return libc_dup(fd); } si = swrap_get_socket_info(idx); dup_fd = libc_dup(fd); if (dup_fd == -1) { int saved_errno = errno; errno = saved_errno; return -1; } SWRAP_LOCK_SI(si); swrap_inc_refcount(si); SWRAP_UNLOCK_SI(si); /* Make sure we don't have an entry for the fd */ swrap_remove_stale(dup_fd); set_socket_info_index(dup_fd, idx); return dup_fd; } int dup(int fd) { return swrap_dup(fd); } /**************************** * DUP2 ***************************/ static int swrap_dup2(int fd, int newfd) { struct socket_info *si; int dup_fd, idx; idx = find_socket_info_index(fd); if (idx == -1) { return libc_dup2(fd, newfd); } si = swrap_get_socket_info(idx); if (fd == newfd) { /* * According to the manpage: * * "If oldfd is a valid file descriptor, and newfd has the same * value as oldfd, then dup2() does nothing, and returns newfd." */ return newfd; } if (find_socket_info(newfd)) { /* dup2() does an implicit close of newfd, which we * need to emulate */ swrap_close(newfd); } dup_fd = libc_dup2(fd, newfd); if (dup_fd == -1) { int saved_errno = errno; errno = saved_errno; return -1; } SWRAP_LOCK_SI(si); swrap_inc_refcount(si); SWRAP_UNLOCK_SI(si); /* Make sure we don't have an entry for the fd */ swrap_remove_stale(dup_fd); set_socket_info_index(dup_fd, idx); return dup_fd; } int dup2(int fd, int newfd) { return swrap_dup2(fd, newfd); } /**************************** * FCNTL ***************************/ static int swrap_vfcntl(int fd, int cmd, va_list va) { struct socket_info *si; int rc, dup_fd, idx; idx = find_socket_info_index(fd); if (idx == -1) { return libc_vfcntl(fd, cmd, va); } si = swrap_get_socket_info(idx); switch (cmd) { case F_DUPFD: dup_fd = libc_vfcntl(fd, cmd, va); if (dup_fd == -1) { int saved_errno = errno; errno = saved_errno; return -1; } SWRAP_LOCK_SI(si); swrap_inc_refcount(si); SWRAP_UNLOCK_SI(si); /* Make sure we don't have an entry for the fd */ swrap_remove_stale(dup_fd); set_socket_info_index(dup_fd, idx); rc = dup_fd; break; default: rc = libc_vfcntl(fd, cmd, va); break; } return rc; } int fcntl(int fd, int cmd, ...) { va_list va; int rc; va_start(va, cmd); rc = swrap_vfcntl(fd, cmd, va); va_end(va); return rc; } /**************************** * EVENTFD ***************************/ #ifdef HAVE_EVENTFD static int swrap_eventfd(int count, int flags) { int fd; fd = libc_eventfd(count, flags); if (fd != -1) { swrap_remove_stale(fd); } return fd; } #ifdef HAVE_EVENTFD_UNSIGNED_INT int eventfd(unsigned int count, int flags) #else int eventfd(int count, int flags) #endif { return swrap_eventfd(count, flags); } #endif #ifdef HAVE_PLEDGE int pledge(const char *promises, const char *paths[]) { (void)promises; /* unused */ (void)paths; /* unused */ return 0; } #endif /* HAVE_PLEDGE */ static void swrap_thread_prepare(void) { /* * This function should only be called here!! * * We bind all symobls to avoid deadlocks of the fork is * interrupted by a signal handler using a symbol of this * library. */ swrap_bind_symbol_all(); SWRAP_LOCK_ALL; } static void swrap_thread_parent(void) { SWRAP_UNLOCK_ALL; } static void swrap_thread_child(void) { SWRAP_UNLOCK_ALL; } /**************************** * CONSTRUCTOR ***************************/ void swrap_constructor(void) { int ret; /* * If we hold a lock and the application forks, then the child * is not able to unlock the mutex and we are in a deadlock. * This should prevent such deadlocks. */ pthread_atfork(&swrap_thread_prepare, &swrap_thread_parent, &swrap_thread_child); ret = socket_wrapper_init_mutex(&sockets_mutex); if (ret != 0) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to initialize pthread mutex"); exit(-1); } ret = socket_wrapper_init_mutex(&socket_reset_mutex); if (ret != 0) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to initialize pthread mutex"); exit(-1); } ret = socket_wrapper_init_mutex(&first_free_mutex); if (ret != 0) { SWRAP_LOG(SWRAP_LOG_ERROR, "Failed to initialize pthread mutex"); exit(-1); } } /**************************** * DESTRUCTOR ***************************/ /* * This function is called when the library is unloaded and makes sure that * sockets get closed and the unix file for the socket are unlinked. */ void swrap_destructor(void) { size_t i; if (socket_fds_idx != NULL) { for (i = 0; i < socket_fds_max; ++i) { if (socket_fds_idx[i] != -1) { swrap_close(i); } } SAFE_FREE(socket_fds_idx); } SAFE_FREE(sockets); if (swrap.libc.handle != NULL) { dlclose(swrap.libc.handle); } if (swrap.libc.socket_handle) { dlclose(swrap.libc.socket_handle); } }