[GNUnet-SVN] r19129 - in gnunet: . src/dht src/dns src/dv src/transport src/util src/vpn

[gnunet]

Author: grothoff
Date: 2012-01-13 23:10:16 +0100 (Fri, 13 Jan 2012)
New Revision: 19129

Modified:
   gnunet/configure.ac
   gnunet/src/dht/dht.conf.in
   gnunet/src/dns/Makefile.am
   gnunet/src/dns/dns.conf.in
   gnunet/src/dv/dv.conf.in
   gnunet/src/transport/transport.conf.in
   gnunet/src/util/service.c
   gnunet/src/vpn/vpn.conf.in
Log:
improving code and build system to be in line with gnunet access control model 
for services as described at https://gnunet.org/gnunet-access-control-model

Modified: gnunet/configure.ac
===================================================================
--- gnunet/configure.ac 2012-01-13 21:33:47 UTC (rev 19128)
+++ gnunet/configure.ac 2012-01-13 22:10:16 UTC (rev 19129)
@@ -751,6 +751,28 @@
 AC_SUBST(SUDO_BINARY)
 
 
+# test for gnunetdns group name
+GNUNETDNS_GROUP=gnunetdns
+AC_MSG_CHECKING(for gnunetdns group name)
+AC_ARG_WITH(gnunetdns,
+  [  --with-gnunetdns=GRPNAME       name for gnunetdns group],
+  [AC_MSG_RESULT("$with_gnunetdns")
+   case $with_gnunetdns in
+   no)
+     GNUNETDNS_GROUP=gnunet
+     ;;
+   yes)
+     GNUNETDNS_GROUP=gnunetdns
+     ;;
+   *)
+     GNUNETDNS_GROUP=$with_gnunetdns
+    ;;
+   esac
+  ],
+  [AC_MSG_RESULT([gnunetdns])])
+AC_SUBST(GNUNETDNS_GROUP)
+
+
 # should 'make check' run tests?
 AC_MSG_CHECKING(whether to run tests)
 AC_ARG_ENABLE([testruns],

Modified: gnunet/src/dht/dht.conf.in
===================================================================
--- gnunet/src/dht/dht.conf.in  2012-01-13 21:33:47 UTC (rev 19128)
+++ gnunet/src/dht/dht.conf.in  2012-01-13 22:10:16 UTC (rev 19129)
@@ -9,6 +9,7 @@
 ACCEPT_FROM6 = ::1;
 BUCKET_SIZE = 4
 UNIXPATH = /tmp/gnunet-service-dht.sock
+# This could be relaxed...
 UNIX_MATCH_UID = YES
 UNIX_MATCH_GID = YES
 # DISABLE_SOCKET_FORWARDING = NO

Modified: gnunet/src/dns/Makefile.am
===================================================================
--- gnunet/src/dns/Makefile.am  2012-01-13 21:33:47 UTC (rev 19128)
+++ gnunet/src/dns/Makefile.am  2012-01-13 22:10:16 UTC (rev 19129)
@@ -20,8 +20,11 @@
 install-exec-hook:
        $(SUDO_BINARY) chown root:root $(bindir)/gnunet-helper-hijack-dns || 
true
        $(SUDO_BINARY) chmod u+s $(bindir)/gnunet-helper-hijack-dns || true
-       $(SUDO_BINARY) chown root:root $(bindir)/gnunet-helper-dns || true
-       $(SUDO_BINARY) chmod u+s $(bindir)/gnunet-helper-dns || true
+       $(SUDO_BINARY) chown root $(bindir)/gnunet-helper-dns || true
+       $(SUDO_BINARY) chgrp $(GNUNETDNS_GROUP) $(bindir)/gnunet-helper-dns || 
true
+       $(SUDO_BINARY) chmod 4750 $(bindir)/gnunet-helper-dns || true
+       $(SUDO_BINARY) chgrp $(GNUNETDNS_GROUP) 
$(bindir)/gnunet-service-dns-new || true
+       $(SUDO_BINARY) chmod 2755 $(bindir)/gnunet-helper-dns || true
 else
 install-exec-hook:
 endif

Modified: gnunet/src/dns/dns.conf.in
===================================================================
--- gnunet/src/dns/dns.conf.in  2012-01-13 21:33:47 UTC (rev 19128)
+++ gnunet/src/dns/dns.conf.in  2012-01-13 22:10:16 UTC (rev 19129)
@@ -5,10 +5,9 @@
 HOME = $SERVICEHOME
 CONFIG = $DEFAULTCONFIG
 BINARY = gnunet-service-dns
-ACCEPT_FROM = 127.0.0.1;
-ACCEPT_FROM6 = ::1;
 UNIXPATH = /tmp/gnunet-service-dns.sock
-
+UNIX_MATCH_UID = YES
+UNIX_MATCH_GID = YES
 PROVIDE_EXIT = YES
 IFNAME = gnunet-dns
 

Modified: gnunet/src/dv/dv.conf.in
===================================================================
--- gnunet/src/dv/dv.conf.in    2012-01-13 21:33:47 UTC (rev 19128)
+++ gnunet/src/dv/dv.conf.in    2012-01-13 22:10:16 UTC (rev 19129)
@@ -9,6 +9,8 @@
 HOSTNAME = localhost
 @UNIXONLY@ PORT = 2571
 UNIXPATH = /tmp/gnunet-service-dv.sock
+UNIX_MATCH_UID = YES
+UNIX_MATCH_GID = YES
 # ACCEPT_FROM =
 # ACCEPT_FROM6 =
 # REJECT_FROM =

Modified: gnunet/src/transport/transport.conf.in
===================================================================
--- gnunet/src/transport/transport.conf.in      2012-01-13 21:33:47 UTC (rev 
19128)
+++ gnunet/src/transport/transport.conf.in      2012-01-13 22:10:16 UTC (rev 
19129)
@@ -12,6 +12,7 @@
 PLUGINS = tcp
 UNIXPATH = /tmp/gnunet-service-transport.sock
 BLACKLIST_FILE = $SERVICEHOME/blacklist
+# This could possibly be relaxed
 UNIX_MATCH_UID = YES
 UNIX_MATCH_GID = YES
 # DISABLE_SOCKET_FORWARDING = NO

Modified: gnunet/src/util/service.c
===================================================================
--- gnunet/src/util/service.c   2012-01-13 21:33:47 UTC (rev 19128)
+++ gnunet/src/util/service.c   2012-01-13 22:10:16 UTC (rev 19129)
@@ -501,14 +501,18 @@
   int require_found;
 
   /**
-   * Do we require a matching UID for UNIX domain socket
-   * connections?
+   * Do we require a matching UID for UNIX domain socket connections?
+   * GNUNET_NO means that the UID does not have to match (however,
+   * "match_gid" may still impose other access control checks).
    */
   int match_uid;
 
   /**
-   * Do we require a matching GID for UNIX domain socket
-   * connections?
+   * Do we require a matching GID for UNIX domain socket connections?
+   * Ignored if "match_uid" is GNUNET_YES.  Note that this is about
+   * checking that the client's UID is in our group OR that the
+   * client's GID is our GID.  If both "match_gid" and "match_uid" are
+   * "GNUNET_NO", all users on the local system have access.
    */
   int match_gid;
 
@@ -617,15 +621,50 @@
 #ifndef WINDOWS
   case AF_UNIX:
     ret = GNUNET_OK;            /* always OK for now */
-    if ((sctx->match_uid == GNUNET_YES) || (sctx->match_gid == GNUNET_YES))
-      ret = GNUNET_NO;
-    if ((uc != NULL) &&
-        ((sctx->match_uid != GNUNET_YES) || (uc->uid == geteuid ()) ||
-         (uc->uid == getuid ())) && ((sctx->match_gid != GNUNET_YES) ||
-                                     (uc->gid == getegid ()) ||
-                                     (uc->gid == getgid ())))
-      ret = GNUNET_YES;
-    else
+    if (sctx->match_uid == GNUNET_YES) 
+    {
+      /* UID match required */
+      ret = (uc != NULL) && (uc->uid == geteuid ());
+    }
+    else if (sctx->match_gid == GNUNET_YES) 
+    {
+      /* group match required */
+      if (uc == NULL) 
+      {
+       /* no credentials, group match not possible */
+       ret = GNUNET_NO;
+      }
+      else
+      {
+       struct group *grp;
+       unsigned int i;
+
+       if (uc->gid != getegid())
+       {
+         /* default group did not match, but maybe the user is in our group, 
let's check */
+         grp = getgrgid (getegid ());
+         if (NULL == grp)
+         {
+           GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "getgrgid");
+           return GNUNET_NO;
+         }
+         ret = GNUNET_NO;
+         for (i=0; NULL != grp->gr_mem[i]; i++)
+         {
+           struct passwd *nam = getpwnam (grp->gr_mem[i]);
+           if (NULL == nam)
+             continue; /* name in group that is not in user DB !? */
+           if (nam->pw_uid == uc->uid)
+           {
+             /* yes, uid is in our group, allow! */
+             ret = GNUNET_YES;
+             break;
+           }
+         }
+       }
+      }
+    }
+    if (GNUNET_NO == ret)
       LOG (GNUNET_ERROR_TYPE_WARNING, _("Access denied to UID %d / GID %d\n"),
            (uc == NULL) ? -1 : uc->uid, (uc == NULL) ? -1 : uc->gid);
     break;

Modified: gnunet/src/vpn/vpn.conf.in
===================================================================
--- gnunet/src/vpn/vpn.conf.in  2012-01-13 21:33:47 UTC (rev 19128)
+++ gnunet/src/vpn/vpn.conf.in  2012-01-13 22:10:16 UTC (rev 19129)
@@ -8,6 +8,8 @@
 ACCEPT_FROM = 127.0.0.1;
 ACCEPT_FROM6 = ::1;
 UNIXPATH = /tmp/gnunet-service-vpn.sock
+UNIX_MATCH_UID = YES
+UNIX_MATCH_GID = YES
 
 IPV6ADDR = 1234::1
 IPV6PREFIX = 32