- djm@cvs.openbsd.org 2010/02/09 06:18:46

     [auth.c]
     unbreak ChrootDirectory+internal-sftp by skipping check for executable
     shell when chrooting; reported by danh AT wzrd.com; ok dtucker@

1 files changed, 21 insertions, 36 deletions

diff --git a/auth.c b/auth.c
index da87807a8..3005f815e 100644
--- a/auth.c
+++ b/auth.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth.c,v 1.83 2010/01/13 23:47:26 djm Exp $ */
+/* $OpenBSD: auth.c,v 1.84 2010/02/09 06:18:46 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  *
@@ -95,7 +95,6 @@ allowed_user(struct passwd * pw)
 {
         struct stat st;
         const char *hostname = NULL, *ipaddr = NULL, *passwd = NULL;
-        char *shell, *tmp, *chroot_path;
         u_int i;
 #ifdef USE_SHADOW
         struct spwd *spw = NULL;
@@ -153,43 +152,29 @@ allowed_user(struct passwd * pw)
         }
 
         /*
-         * Get the shell from the password data.  An empty shell field is
-         * legal, and means /bin/sh.
+         * Deny if shell does not exist or is not executable unless we
+         * are chrooting.
          */
-        shell = xstrdup((pw->pw_shell[0] == '\0') ?
-            _PATH_BSHELL : pw->pw_shell);
-
-        /*
-         * Amend shell if chroot is requested.
-         */
-        if (options.chroot_directory != NULL &&
-            strcasecmp(options.chroot_directory, "none") != 0) {
-                tmp = tilde_expand_filename(options.chroot_directory,
-                    pw->pw_uid);
-                chroot_path = percent_expand(tmp, "h", pw->pw_dir,
-                    "u", pw->pw_name, (char *)NULL);
-                xfree(tmp);
-                xasprintf(&tmp, "%s/%s", chroot_path, shell);
-                xfree(shell);
-                shell = tmp;
-                free(chroot_path);
-        }
-
-        /* deny if shell does not exists or is not executable */
-        if (stat(shell, &st) != 0) {
-                logit("User %.100s not allowed because shell %.100s does not exist",
-                    pw->pw_name, shell);
-                xfree(shell);
-                return 0;
-        }
-        if (S_ISREG(st.st_mode) == 0 ||
-            (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)) == 0) {
-                logit("User %.100s not allowed because shell %.100s is not executable",
-                    pw->pw_name, shell);
+        if (options.chroot_directory == NULL ||
+            strcasecmp(options.chroot_directory, "none") == 0) {
+                char *shell = xstrdup((pw->pw_shell[0] == '\0') ?
+                    _PATH_BSHELL : pw->pw_shell); /* empty = /bin/sh */
+
+                if (stat(shell, &st) != 0) {
+                        logit("User %.100s not allowed because shell %.100s "
+                            "does not exist", pw->pw_name, shell);
+                        xfree(shell);
+                        return 0;
+                }
+                if (S_ISREG(st.st_mode) == 0 ||
+                    (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP)) == 0) {
+                        logit("User %.100s not allowed because shell %.100s "
+                            "is not executable", pw->pw_name, shell);
+                        xfree(shell);
+                        return 0;
+                }
                 xfree(shell);
-                return 0;
         }
-        xfree(shell);
 
         if (options.num_deny_users > 0 || options.num_allow_users > 0 ||
             options.num_deny_groups > 0 || options.num_allow_groups > 0) {