pwrap: Create two pwrap_init() functions

One for pam_start() and one for pam_start_confdir() support.

Signed-off-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>

1 files changed, 132 insertions, 13 deletions

diff --git a/src/pam_wrapper.c b/src/pam_wrapper.c
index 088754b..3e5ebbe 100644
--- a/src/pam_wrapper.c
+++ b/src/pam_wrapper.c
@@ -804,7 +804,137 @@ static void pwrap_clean_stale_dirs(const char *dir)
 	return;
 }
 
-#ifndef HAVE_PAM_START_CONFDIR
+#ifdef HAVE_PAM_START_CONFDIR
+static void pwrap_init(void)
+{
+	char tmp_config_dir[] = "/tmp/pam.X";
+	size_t len = strlen(tmp_config_dir);
+	const char *env;
+	struct stat sb;
+	int rc;
+	unsigned i;
+	ssize_t ret;
+	FILE *pidfile;
+	char pidfile_path[1024] = { 0 };
+	char letter;
+
+	if (!pam_wrapper_enabled()) {
+		return;
+	}
+
+	if (pwrap.initialised) {
+		return;
+	}
+
+	/*
+	 * The name is selected to match/replace /etc/pam.d
+	 * We start from a random alphanum trying letters until
+	 * an available directory is found.
+	 */
+	letter = 48 + (getpid() % 70);
+	for (i = 0; i < 127; i++) {
+		if (isalpha(letter) || isdigit(letter)) {
+			tmp_config_dir[len - 1] = letter;
+
+			rc = lstat(tmp_config_dir, &sb);
+			if (rc == 0) {
+				PWRAP_LOG(PWRAP_LOG_TRACE,
+					  "Check if pam_wrapper dir %s is a "
+					  "stale directory",
+					  tmp_config_dir);
+				pwrap_clean_stale_dirs(tmp_config_dir);
+			} else if (rc < 0) {
+				if (errno != ENOENT) {
+					continue;
+				}
+				break; /* found */
+			}
+		}
+
+		letter++;
+		letter %= 127;
+	}
+
+	if (i == 127) {
+		PWRAP_LOG(PWRAP_LOG_ERROR,
+			  "Failed to find a possible path to create "
+			  "pam_wrapper config dir: %s",
+			  tmp_config_dir);
+		exit(1);
+	}
+
+	PWRAP_LOG(PWRAP_LOG_DEBUG, "Initialize pam_wrapper");
+
+	pwrap.config_dir = strdup(tmp_config_dir);
+	if (pwrap.config_dir == NULL) {
+		PWRAP_LOG(PWRAP_LOG_ERROR,
+			  "No memory");
+		exit(1);
+	}
+	PWRAP_LOG(PWRAP_LOG_TRACE,
+		  "pam_wrapper config dir: %s",
+		  tmp_config_dir);
+
+	rc = mkdir(pwrap.config_dir, 0755);
+	if (rc != 0) {
+		PWRAP_LOG(PWRAP_LOG_ERROR,
+			  "Failed to create pam_wrapper config dir: %s - %s",
+			  tmp_config_dir, strerror(errno));
+	}
+
+	/* Create file with the PID of the the process */
+	ret = snprintf(pidfile_path, sizeof(pidfile_path),
+		       "%s/pid", pwrap.config_dir);
+	if (ret < 0) {
+		p_rmdirs(pwrap.config_dir);
+		exit(1);
+	}
+
+	pidfile = fopen(pidfile_path, "w");
+	if (pidfile == NULL) {
+		p_rmdirs(pwrap.config_dir);
+		exit(1);
+	}
+
+	rc = fprintf(pidfile, "%d", getpid());
+	fclose(pidfile);
+	if (rc <= 0) {
+		p_rmdirs(pwrap.config_dir);
+		exit(1);
+	}
+
+	pwrap.libpam_so = strdup(PAM_LIBRARY);
+	if (pwrap.libpam_so == NULL) {
+		PWRAP_LOG(PWRAP_LOG_ERROR, "No memory");
+		p_rmdirs(pwrap.config_dir);
+		exit(1);
+	}
+
+	PWRAP_LOG(PWRAP_LOG_TRACE, "Using libpam path: %s", pwrap.libpam_so);
+
+	pwrap.initialised = true;
+
+	env = getenv("PAM_WRAPPER_SERVICE_DIR");
+	if (env == NULL) {
+		PWRAP_LOG(PWRAP_LOG_ERROR, "No config file");
+		p_rmdirs(pwrap.config_dir);
+		exit(1);
+	}
+
+	rc = copy_confdir(env);
+	if (rc != 0) {
+		PWRAP_LOG(PWRAP_LOG_ERROR, "Failed to copy config files");
+		p_rmdirs(pwrap.config_dir);
+		exit(1);
+	}
+
+	setenv("PAM_WRAPPER_RUNTIME_DIR", pwrap.config_dir, 1);
+
+	PWRAP_LOG(PWRAP_LOG_DEBUG, "Successfully initialized pam_wrapper");
+}
+
+#else /* HAVE_PAM_START_CONFDIR */
+
 static int pso_copy(const char *src, const char *dst, const char *pdir, mode_t mode)
 {
 #define PSO_COPY_READ_SIZE 16
@@ -923,7 +1053,6 @@ out:
 	return rc;
 #undef PSO_COPY_READ_SIZE
 }
-#endif /* HAVE_PAM_START_CONFDIR */
 
 static void pwrap_init(void)
 {
@@ -933,10 +1062,8 @@ static void pwrap_init(void)
 	struct stat sb;
 	int rc;
 	unsigned i;
-#ifndef HAVE_PAM_START_CONFDIR
 	char pam_library[128] = { 0 };
 	char libpam_path[1024] = { 0 };
-#endif
 	ssize_t ret;
 	FILE *pidfile;
 	char pidfile_path[1024] = { 0 };
@@ -1027,14 +1154,6 @@ static void pwrap_init(void)
 		exit(1);
 	}
 
-#ifdef HAVE_PAM_START_CONFDIR
-	pwrap.libpam_so = strdup(PAM_LIBRARY);
-	if (pwrap.libpam_so == NULL) {
-		PWRAP_LOG(PWRAP_LOG_ERROR, "No memory");
-		p_rmdirs(pwrap.config_dir);
-		exit(1);
-	}
-#else /* HAVE_PAM_START_CONFDIR */
 	/* create lib subdirectory */
 	snprintf(libpam_path,
 		 sizeof(libpam_path),
@@ -1119,7 +1238,6 @@ static void pwrap_init(void)
 		p_rmdirs(pwrap.config_dir);
 		exit(1);
 	}
-#endif /* HAVE_PAM_START_CONFDIR */
 
 	PWRAP_LOG(PWRAP_LOG_TRACE, "Using libpam path: %s", pwrap.libpam_so);
 
@@ -1143,6 +1261,7 @@ static void pwrap_init(void)
 
 	PWRAP_LOG(PWRAP_LOG_DEBUG, "Successfully initialized pam_wrapper");
 }
+#endif /* HAVE_PAM_START_CONFDIR */
 
 bool pam_wrapper_enabled(void)
 {