* src/su.c: environ is provided by <unistd.h>.

	* src/su.c: Added function prototypes.
	* src/su.c: Rename shellstr parameter to shellname to avoid
	collision with static variable.
	* NEWS, src/su.c: Added support for PAM modules which change
	PAM_USER.

diff --git a/ChangeLog b/ChangeLog
index 04cd67892f5a9897d66dc3384aeddb0c04bf0baa..0a62f68cf4c633d01a1329dd0c99ca63142ccaa2 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2011-06-16  Nicolas François  <nicolas.francois@centraliens.net>
+
+       * src/su.c: environ is provided by <unistd.h>.
+       * src/su.c: Added function prototypes.
+       * src/su.c: Rename shellstr parameter to shellname to avoid
+       collision with static variable.
+       * NEWS, src/su.c: Added support for PAM modules which change
+       PAM_USER.
+
 2011-06-13  Nicolas François  <nicolas.francois@centraliens.net>
 
        * src/su.c (prepare_pam_close_session): Extract the creation of a

diff --git a/NEWS b/NEWS
index 4a8c16088e251fc622b3cfda0226cc8338b80b3d..f544a851426042cdc1517e39ee094dfb4d91332d 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -48,6 +48,7 @@ shadow-4.1.4.3 -> shadow-4.1.5                                        UNRELEASED
     caller's privileges.
   * Close PAM sessions as root. This will be more friendly to PAM modules
     like pam_mount or pam_systemd.
+  * Added support for PAM modules which change PAM_USER.
 - newgrp, sg, groupmems
   * Fix parsing of gshadow entries.
 - useradd
@@ -67,6 +68,7 @@ shadow-4.1.4.3 -> shadow-4.1.5                                        UNRELEASED
   * Updated Czech translation.
   * Updated Danish translation.
   * Updated French translation.
+  * Updated French man pages translation.
   * Updated German translation.
   * Updated German man pages translation.
   * Updated Japanese translation.

diff --git a/src/su.c b/src/su.c
index 67c3e6a0ec4d771eac39c28749875ac47c2bbdb9..84ac42b9251efaa5fed35b94dfe13cd83e31be7e 100644 (file)
--- a/src/su.c
+++ b/src/su.c
@@ -115,13 +115,12 @@ static pid_t pid_child = 0;
  * External identifiers
  */
 
-extern char **newenvp;
-extern char **environ;
-extern size_t newenvc;
+extern char **newenvp; /* libmisc/env.c */
+extern size_t newenvc; /* libmisc/env.c */
 
 /* local function prototypes */
 
-static void execve_shell (const char *shellstr,
+static void execve_shell (const char *shellname,
                           char *args[],
                           char *const envp[]);
 #ifdef USE_PAM
@@ -131,6 +130,8 @@ static void prepare_pam_close_session (void);
 static RETSIGTYPE die (int);
 static bool iswheel (const char *);
 #endif                         /* !USE_PAM */
+static bool restricted_shell (const char *shellname);
+static void su_failure (const char *tty, bool su_to_root);
 static struct passwd * check_perms (void);
 #ifdef USE_PAM
 static void check_perms_pam (struct passwd *pw);
@@ -139,6 +140,7 @@ static void check_perms_nopam (struct passwd *pw);
 #endif                         /* !USE_PAM */
 static void save_caller_context (char **argv);
 static void process_flags (int argc, char **argv);
+static void set_environment (struct passwd *pw);
 
 #ifndef USE_PAM
 /*
@@ -190,13 +192,13 @@ static RETSIGTYPE kill_child (int unused(s))
 #endif                         /* USE_PAM */
 
 /* borrowed from GNU sh-utils' "su.c" */
-static bool restricted_shell (const char *shellstr)
+static bool restricted_shell (const char *shellname)
 {
        char *line;
 
        setusershell ();
        while ((line = getusershell ()) != NULL) {
-               if (('#' != *line) && (strcmp (line, shellstr) == 0)) {
+               if (('#' != *line) && (strcmp (line, shellname) == 0)) {
                        endusershell ();
                        return false;
                }
@@ -224,15 +226,15 @@ static void su_failure (const char *tty, bool su_to_root)
  * execve_shell - Execute a shell with execve, or interpret it with
  * /bin/sh
  */
-static void execve_shell (const char *shellstr,
+static void execve_shell (const char *shellname,
                           char *args[],
                           char *const envp[])
 {
        int err;
-       (void) execve (shellstr, (char **) args, envp);
+       (void) execve (shellname, (char **) args, envp);
        err = errno;
 
-       if (access (shellstr, R_OK|X_OK) == 0) {
+       if (access (shellname, R_OK|X_OK) == 0) {
                /*
                 * Assume this is a shell script (with no shebang).
                 * Interpret it with /bin/sh
@@ -245,7 +247,7 @@ static void execve_shell (const char *shellstr,
                targs = (char **) xmalloc ((n_args + 3) * sizeof (args[0]));
                targs[0] = "sh";
                targs[1] = "-";
-               targs[2] = xstrdup (shellstr);
+               targs[2] = xstrdup (shellname);
                targs[n_args+2] = NULL;
                while (1 != n_args) {
                        targs[n_args+1] = args[n_args - 1];
@@ -570,24 +572,57 @@ static void check_perms_nopam (struct passwd *pw)
  */
 static struct passwd * check_perms (void)
 {
+#ifdef USE_PAM
+       const char *tmp_name;
+       int ret;
+#endif                         /* !USE_PAM */
        /*
         * The password file entries for the user is gotten and the account
         * validated.
         */
        struct passwd *pw = xgetpwnam (name);
        if (NULL == pw) {
-               (void) fprintf (stderr, _("Unknown id: %s\n"), name);
-               closelog ();
-               exit (1);
+               (void) fprintf (stderr,
+                               _("No passwd entry for user '%s'\n"), name);
+               SYSLOG ((LOG_ERR, "No passwd entry for user '%s'", name));
+               su_failure (caller_tty, true);
        }
 
        (void) signal (SIGINT, SIG_IGN);
        (void) signal (SIGQUIT, SIG_IGN);
+
 #ifdef USE_PAM
        check_perms_pam (pw);
+       /* PAM authentication can request a change of account */
+       ret = pam_get_item(pamh, PAM_USER, (const void **) &tmp_name);
+       if (ret != PAM_SUCCESS) {
+               SYSLOG((LOG_ERR, "pam_get_item: internal PAM error\n"));
+               (void) fprintf (stderr,
+                               "%s: Internal PAM error retrieving username\n",
+                               Prog);
+               (void) pam_end (pamh, ret);
+               su_failure (caller_tty, 0 == pw->pw_uid);
+       }
+       if (strcmp (name, tmp_name) != 0) {
+               SYSLOG ((LOG_INFO,
+                        "Change user from '%s' to '%s' as requested by PAM",
+                        name, tmp_name));
+               strncpy (name, tmp_name, sizeof(name) - 1);
+               name[sizeof(name) - 1] = '\0';
+               pw = xgetpwnam (name);
+               if (NULL == pw) {
+                       (void) fprintf (stderr,
+                                       _("No passwd entry for user '%s'\n"),
+                                       name);
+                       SYSLOG ((LOG_ERR,
+                                "No passwd entry for user '%s'", name));
+                       su_failure (caller_tty, true);
+               }
+       }
 #else                          /* !USE_PAM */
        check_perms_nopam (pw);
 #endif                         /* !USE_PAM */
+
        (void) signal (SIGINT, SIG_DFL);
        (void) signal (SIGQUIT, SIG_DFL);
 
@@ -659,7 +694,7 @@ static void save_caller_context (char **argv)
                         Prog);
                SYSLOG ((LOG_WARN, "Cannot determine the user name of the caller (UID %lu)",
                         (unsigned long) caller_uid));
-               su_failure (caller_tty, true); // FIXME: at this time I do not know the target UID
+               su_failure (caller_tty, true); /* unknown target UID*/
        }
        STRFCPY (caller_name, pw->pw_name);