1 files changed, 158 insertions, 0 deletions
diff --git a/modules/pam_motd/pam_motd.c b/modules/pam_motd/pam_motd.c
new file mode 100644
index 0000000..cc828d7
--- /dev/null
+++ b/modules/pam_motd/pam_motd.c
@@ -0,0 +1,158 @@
+/* pam_motd module */
+
+/*
+ * Modified for pam_motd by Ben Collins <bcollins@debian.org>
+ *
+ * Based off of:
+ * $Id$
+ *
+ * Written by Michael K. Johnson <johnsonm@redhat.com> 1996/10/24
+ *
+ */
+
+#include "config.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <pwd.h>
+#include <syslog.h>
+
+#include <security/_pam_macros.h>
+#include <security/pam_ext.h>
+/*
+ * here, we make a definition for the externally accessible function
+ * in this file (this definition is required for static a module
+ * but strongly encouraged generally) it is used to instruct the
+ * modules include file to define the function prototypes.
+ */
+
+#define PAM_SM_SESSION
+#define DEFAULT_MOTD	"/etc/motd"
+#define DEFAULT_MOTD_D	"/etc/motd.d"
+
+#include <security/pam_modules.h>
+#include <security/pam_modutil.h>
+
+/* --- session management functions (only) --- */
+
+int
+pam_sm_close_session (pam_handle_t *pamh UNUSED, int flags UNUSED,
+		      int argc UNUSED, const char **argv UNUSED)
+{
+     return PAM_IGNORE;
+}
+
+static char default_motd[] = DEFAULT_MOTD;
+static char default_motd_dir[] = DEFAULT_MOTD_D;
+
+static void try_to_display_fd(pam_handle_t *pamh, int fd)
+{
+    struct stat st;
+    char *mtmp = NULL;
+
+    /* fill in message buffer with contents of motd */
+    if ((fstat(fd, &st) < 0) || !st.st_size || st.st_size > 0x10000)
+	return;
+
+    if (!(mtmp = malloc(st.st_size+1)))
+	return;
+
+    if (pam_modutil_read(fd, mtmp, st.st_size) == st.st_size) {
+	if (mtmp[st.st_size-1] == '\n')
+	    mtmp[st.st_size-1] = '\0';
+	else
+	    mtmp[st.st_size] = '\0';
+
+	pam_info (pamh, "%s", mtmp);
+    }
+
+    _pam_drop(mtmp);
+}
+
+static void try_to_display_directory(pam_handle_t *pamh, const char *dirname)
+{
+    DIR *dirp;
+
+    dirp = opendir(dirname);
+
+    if (dirp != NULL) {
+	struct dirent *entry;
+
+	while ((entry = readdir(dirp))) {
+	    int fd = openat(dirfd(dirp), entry->d_name, O_RDONLY);
+
+	    if (fd >= 0) {
+		try_to_display_fd(pamh, fd);
+		close(fd);
+	    }
+	}
+
+	closedir(dirp);
+    }
+}
+
+int pam_sm_open_session(pam_handle_t *pamh, int flags,
+			int argc, const char **argv)
+{
+    int retval = PAM_IGNORE;
+    const char *motd_path = NULL;
+    const char *motd_dir_path = NULL;
+
+    if (flags & PAM_SILENT) {
+	return retval;
+    }
+
+    for (; argc-- > 0; ++argv) {
+        if (!strncmp(*argv,"motd=",5)) {
+
+            motd_path = 5 + *argv;
+            if (*motd_path != '\0') {
+                D(("set motd path: %s", motd_path));
+	    } else {
+		motd_path = NULL;
+		pam_syslog(pamh, LOG_ERR,
+			   "motd= specification missing argument - ignored");
+	    }
+	}
+	else if (!strncmp(*argv,"motd_dir=",9)) {
+
+            motd_dir_path = 9 + *argv;
+            if (*motd_dir_path != '\0') {
+                D(("set motd.d path: %s", motd_dir_path));
+	    } else {
+		motd_dir_path = NULL;
+		pam_syslog(pamh, LOG_ERR,
+			   "motd_dir= specification missing argument - ignored");
+	    }
+	}
+	else
+	    pam_syslog(pamh, LOG_ERR, "unknown option: %s", *argv);
+    }
+
+    if (motd_path == NULL && motd_dir_path == NULL) {
+	motd_path = default_motd;
+	motd_dir_path = default_motd_dir;
+    }
+
+    if (motd_path != NULL) {
+	int fd = open(motd_path, O_RDONLY, 0);
+
+	if (fd >= 0) {
+	    try_to_display_fd(pamh, fd);
+	    close(fd);
+	}
+    }
+
+    if (motd_dir_path != NULL)
+	try_to_display_directory(pamh, motd_dir_path);
+
+    return retval;
+}
+
+/* end of module definition */