upstream: allow sshd_config PermitUserEnvironment to accept a

pattern-list of whitelisted environment variable names in addition to yes|no.

bz#1800, feedback and ok markus@

OpenBSD-Commit-ID: 77dc2b468e0bf04b53f333434ba257008a1fdf24

1 files changed, 36 insertions, 4 deletions

diff --git a/servconf.c b/servconf.c
index cb5786583..a41fdc26a 100644
--- a/servconf.c
+++ b/servconf.c
@@ -1,5 +1,5 @@
 
-/* $OpenBSD: servconf.c,v 1.333 2018/06/19 02:59:41 djm Exp $ */
+/* $OpenBSD: servconf.c,v 1.334 2018/07/03 10:59:35 djm Exp $ */
 /*
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
  *                    All rights reserved
@@ -130,6 +130,7 @@ initialize_server_options(ServerOptions *options)
         options->challenge_response_authentication = -1;
         options->permit_empty_passwd = -1;
         options->permit_user_env = -1;
+        options->permit_user_env_whitelist = NULL;
         options->compression = -1;
         options->rekey_limit = -1;
         options->rekey_interval = -1;
@@ -329,8 +330,10 @@ fill_default_server_options(ServerOptions *options)
                 options->challenge_response_authentication = 1;
         if (options->permit_empty_passwd == -1)
                 options->permit_empty_passwd = 0;
-        if (options->permit_user_env == -1)
+        if (options->permit_user_env == -1) {
                 options->permit_user_env = 0;
+                options->permit_user_env_whitelist = NULL;
+        }
         if (options->compression == -1)
                 options->compression = COMP_DELAYED;
         if (options->rekey_limit == -1)
@@ -1514,7 +1517,29 @@ process_server_config_line(ServerOptions *options, char *line,
 
         case sPermitUserEnvironment:
                 intptr = &options->permit_user_env;
-                goto parse_flag;
+                charptr = &options->permit_user_env_whitelist;
+                arg = strdelim(&cp);
+                if (!arg || *arg == '\0')
+                        fatal("%s line %d: missing argument.",
+                            filename, linenum);
+                value = 0;
+                p = NULL;
+                if (strcmp(arg, "yes") == 0)
+                        value = 1;
+                else if (strcmp(arg, "no") == 0)
+                        value = 0;
+                else {
+                        /* Pattern-list specified */
+                        value = 1;
+                        p = xstrdup(arg);
+                }
+                if (*activep && *intptr == -1) {
+                        *intptr = value;
+                        *charptr = p;
+                        p = NULL;
+                }
+                free(p);
+                break;
 
         case sCompression:
                 intptr = &options->compression;
@@ -2528,7 +2553,6 @@ dump_config(ServerOptions *o)
         dump_cfg_fmtint(sStrictModes, o->strict_modes);
         dump_cfg_fmtint(sTCPKeepAlive, o->tcp_keep_alive);
         dump_cfg_fmtint(sEmptyPasswd, o->permit_empty_passwd);
-        dump_cfg_fmtint(sPermitUserEnvironment, o->permit_user_env);
         dump_cfg_fmtint(sCompression, o->compression);
         dump_cfg_fmtint(sGatewayPorts, o->fwd_opts.gateway_ports);
         dump_cfg_fmtint(sUseDNS, o->use_dns);
@@ -2628,4 +2652,12 @@ dump_config(ServerOptions *o)
                         printf(" %s", o->permitted_listens[i]);
         }
         printf("\n");
+
+        if (o->permit_user_env_whitelist == NULL) {
+                dump_cfg_fmtint(sPermitUserEnvironment, o->permit_user_env);
+        } else {
+                printf("permituserenvironment %s\n",
+                    o->permit_user_env_whitelist);
+        }
+
 }