[patch] Add support for creating a PAM session for daemons

start-stop-daemon.patch (text/plain), 5.25 KB, created by Scott Dial on 2005-03-21 17:33:25 UTC

--- start-stop-daemon.c.orig	2004-05-10 09:21:55.000000000 -0500
+++ start-stop-daemon.c	2005-03-21 20:31:56.000000000 -0500
@@ -21,20 +21,24 @@
  *
  * Modified for Gentoo rc-scripts by Donny Davies <[e-mail]>:
  *   I removed the BSD/Hurd/OtherOS stuff, added #include <stddef.h>
  *   and stuck in a #define VERSION "1.9.18".  Now it compiles without
  *   the whole automake/config.h dance.
  *
  * Updated by Aron Griffis <[e-mail]>:
  *   Fetched updates from Debian's dpkg-1.10.20, including fix for
  *   Gentoo bug 22686 (start-stop-daemon in baselayout doesn't allow
  *   altered nicelevel).
+ *
+ * Updated by Scott Dial <[e-mail]>:
+ *   Provides PAM support, Gentoo bug 64700 (start-stop-daemon doesn't use pam)
+ *
  */
 
 #define VERSION "1.10.20"
 #include <stddef.h>
 
 #define NONRETURNPRINTFFORMAT(x, y) \
 	__attribute__((noreturn, format(printf, x, y)))
 #define NONRETURNING \
 	__attribute__((noreturn))
 
@@ -95,20 +99,25 @@
 #include <pwd.h>
 #include <grp.h>
 #include <sys/ioctl.h>
 #include <sys/types.h>
 #include <sys/termios.h>
 #include <fcntl.h>
 #include <limits.h>
 #include <assert.h>
 #include <ctype.h>
 
+#ifdef USE_PAM
+#	include <security/pam_appl.h>
+#	include <security/pam_misc.h>
+#endif
+
 #ifdef HAVE_ERROR_H
 #  include <error.h>
 #endif
 #ifdef HURD_IHASH_H
   #include <hurd/ihash.h>
 #endif
 
 static int testmode = 0;
 static int quietmode = 0;
 static int exitnodo = 1;
@@ -283,20 +292,21 @@
 "  start-stop-daemon -K|--stop options ...\n"
 "  start-stop-daemon -H|--help\n"
 "  start-stop-daemon -V|--version\n"
 "\n"
 "Options (at least one of --exec|--pidfile|--user is required):\n"
 "  -x|--exec <executable>        program to start/check if it is running\n"
 "  -p|--pidfile <pid-file>       pid file to check\n"
 "  -c|--chuid <name|uid[:group|gid]>\n"
 "  		change to this user/group before starting process\n"
 "  -u|--user <username>|<uid>    stop processes owned by this user\n"
+"		user for PAM session\n"
 "  -g|--group <group|gid>        run process as this group\n"
 "  -n|--name <process-name>      stop processes with this name\n"
 "  -s|--signal <signal>          signal to send (default TERM)\n"
 "  -a|--startas <pathname>       program to start (default is <executable>)\n"
 "  -C|--chdir <directory>        Change to <directory>(default is /)\n"
 "  -N|--nicelevel <incr>         add incr to the process's nice level\n"
 "  -b|--background               force the process to detach\n"
 "  -m|--make-pidfile             create the pidfile before starting\n"
 "  -R|--retry <schedule>         check whether processes die, and retry\n"
 "  -t|--test                     test mode, don't do anything\n"
@@ -1131,25 +1141,33 @@
 x_finished:
 	if (!anykilled) {
 		if (quietmode <= 0)
 			printf("No %s found running; none killed.\n", what_stop);
 		return exitnodo;
 	} else {
 		return 0;
 	}
 }
 
+#ifdef USE_PAM
+// We are not supporting authentication conversations
+static struct pam_conv conv = {NULL, NULL };
+#endif
 
 int main(int argc, char **argv) NONRETURNING;
 int
 main(int argc, char **argv)
 {
+#ifdef USE_PAM
+    pam_handle_t *pamh=NULL;
+    int retval;
+#endif	
 	int devnull_fd = -1;
 #ifdef HAVE_TIOCNOTTY
 	int tty_fd = -1;
 #endif
 	progname = argv[0];
 
 	parse_options(argc, argv);
 	argc -= optind;
 	argv += optind;
 
@@ -1252,20 +1270,48 @@
 		fclose(pidf);
 	}
 	if (changeroot != NULL) {
 		if (chdir(changeroot) < 0)
 			fatal("Unable to chdir() to %s", changeroot);
 		if (chroot(changeroot) < 0)
 			fatal("Unable to chroot() to %s", changeroot);
 	}
 	if (changedir != NULL && chdir(changedir) < 0)
 		fatal("Unable to chdir() to %s", changedir);
+
+// Before we change users, we need to do PAM
+#ifdef USE_PAM
+		// -c	takes priority because it will be what the process ends up running as
+		// -u	comes in second to allow daemons to be started as root (as most require)
+		//			but use the effective session for another user
+		// else we use "nobody" to avoid promoting any daemon
+
+		if(changeuser != NULL)
+			retval = pam_start("start-stop-daemon", changeuser, &conv, &pamh);
+		else if (userspec != NULL)
+			retval = pam_start("start-stop-daemon", userspec, &conv, &pamh);
+		else
+			retval = pam_start("start-stop-daemon", "nobody", &conv, &pamh);
+
+		if(retval == PAM_SUCCESS)
+			retval = pam_authenticate(pamh, PAM_SILENT);
+	
+		if(retval == PAM_SUCCESS)
+			retval = pam_acct_mgmt(pamh, PAM_SILENT);
+			
+		if(retval == PAM_SUCCESS)
+			retval = pam_open_session(pamh, PAM_SILENT);
+			
+		if(retval != PAM_SUCCESS)
+			printf(pam_strerror(pamh, retval));
+#endif
+
 	if (changeuser != NULL) {
  		if (setgid(runas_gid))
  			fatal("Unable to set gid to %d", runas_gid);
 		if (initgroups(changeuser, runas_gid))
 			fatal("Unable to set initgroups() with gid %d", runas_gid);
 		if (setuid(runas_uid))
 			fatal("Unable to set uid to %s", changeuser);
 	}
 	if (background) { /* continue background setup */
 		int i;
@@ -1287,13 +1333,19 @@
 #endif
 
 		/* create a new session */
 #ifdef HAVE_SETSID
 		setsid();
 #else
 		setpgid(0,0);
 #endif
 	}
 	execv(startas, argv);
-	fatal("Unable to start %s: %s", startas, strerror(errno));
+#ifdef USE_PAM
+	if(retval == PAM_SUCCESS)
+		pam_close_session(pamh, PAM_SILENT);
+		
+	pam_end(pamh, retval);
+#endif
+	fatal("Unable to start %s: %s", startas, strerror(errno));	
 }