- djm@cvs.openbsd.org 2010/05/07 11:30:30

     [auth-options.c auth-options.h auth.c auth.h auth2-pubkey.c]
     [key.c servconf.c servconf.h sshd.8 sshd_config.5]
     add some optional indirection to matching of principal names listed
     in certificates. Currently, a certificate must include the a user's name
     to be accepted for authentication. This change adds the ability to
     specify a list of certificate principal names that are acceptable.

     When authenticating using a CA trusted through ~/.ssh/authorized_keys,
     this adds a new principals="name1[,name2,...]" key option.

     For CAs listed through sshd_config's TrustedCAKeys option, a new config
     option "AuthorizedPrincipalsFile" specifies a per-user file containing
     the list of acceptable names.

     If either option is absent, the current behaviour of requiring the
     username to appear in principals continues to apply.

     These options are useful for role accounts, disjoint account namespaces
     and "user@realm"-style naming policies in certificates.

     feedback and ok markus@

1 files changed, 42 insertions, 1 deletions

diff --git a/auth-options.c b/auth-options.c
index 60d5f749b..57a67ec79 100644
--- a/auth-options.c
+++ b/auth-options.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth-options.c,v 1.50 2010/04/16 01:47:26 djm Exp $ */
+/* $OpenBSD: auth-options.c,v 1.51 2010/05/07 11:30:29 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -55,6 +55,9 @@ struct envstring *custom_environment = NULL;
 /* "tunnel=" option. */
 int forced_tun_device = -1;
 
+/* "principals=" option. */
+char *authorized_principals = NULL;
+
 extern ServerOptions options;
 
 void
@@ -76,6 +79,10 @@ auth_clear_options(void)
                 xfree(forced_command);
                 forced_command = NULL;
         }
+        if (authorized_principals) {
+                xfree(authorized_principals);
+                authorized_principals = NULL;
+        }
         forced_tun_device = -1;
         channel_clear_permitted_opens();
 }
@@ -141,6 +148,8 @@ auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum)
                 cp = "command=\"";
                 if (strncasecmp(opts, cp, strlen(cp)) == 0) {
                         opts += strlen(cp);
+                        if (forced_command != NULL)
+                                xfree(forced_command);
                         forced_command = xmalloc(strlen(opts) + 1);
                         i = 0;
                         while (*opts) {
@@ -167,6 +176,38 @@ auth_parse_options(struct passwd *pw, char *opts, char *file, u_long linenum)
                         opts++;
                         goto next_option;
                 }
+                cp = "principals=\"";
+                if (strncasecmp(opts, cp, strlen(cp)) == 0) {
+                        opts += strlen(cp);
+                        if (authorized_principals != NULL)
+                                xfree(authorized_principals);
+                        authorized_principals = xmalloc(strlen(opts) + 1);
+                        i = 0;
+                        while (*opts) {
+                                if (*opts == '"')
+                                        break;
+                                if (*opts == '\\' && opts[1] == '"') {
+                                        opts += 2;
+                                        authorized_principals[i++] = '"';
+                                        continue;
+                                }
+                                authorized_principals[i++] = *opts++;
+                        }
+                        if (!*opts) {
+                                debug("%.100s, line %lu: missing end quote",
+                                    file, linenum);
+                                auth_debug_add("%.100s, line %lu: missing end quote",
+                                    file, linenum);
+                                xfree(authorized_principals);
+                                authorized_principals = NULL;
+                                goto bad_option;
+                        }
+                        authorized_principals[i] = '\0';
+                        auth_debug_add("principals: %.900s",
+                            authorized_principals);
+                        opts++;
+                        goto next_option;
+                }
                 cp = "environment=\"";
                 if (options.permit_user_env &&
                     strncasecmp(opts, cp, strlen(cp)) == 0) {