gpg: Check gpg-agent version before 2.1 migration.

* g10/call-agent.c, g10/call-agent.h (agent_get_version): New.
* g10/migrate.c (migrate_secring): Abort migration if
agent_get_version returns not at least 2.1.0

--
GnuPG-bug-id: 1718

On the first installation of GnuPG 2.1 it is likely that an
old gpg-agent is still running in the environment. In that
case the migration would fail.

Signed-off-by: Andre Heinecke <[email protected]>

1 files changed, 23 insertions, 0 deletions

diff --git a/g10/migrate.c b/g10/migrate.c
index 9a21cfe8e..5cb3512d9 100644
--- a/g10/migrate.c
+++ b/g10/migrate.c
@@ -29,6 +29,7 @@
 #include "keydb.h"
 #include "util.h"
 #include "main.h"
+#include "call-agent.h"
 
 
 #ifdef HAVE_DOSISH_SYSTEM
@@ -46,6 +47,7 @@ migrate_secring (ctrl_t ctrl)
   dotlock_t lockhd = NULL;
   char *secring = NULL;
   char *flagfile = NULL;
+  char *agent_version = NULL;
 
   secring = make_filename (opt.homedir, "secring" EXTSEP_S "gpg", NULL);
   if (access (secring, F_OK))
@@ -72,6 +74,27 @@ migrate_secring (ctrl_t ctrl)
       goto leave;
     }
 
+  if (!agent_get_version (ctrl, &agent_version))
+    {
+      if (!gnupg_compare_version (agent_version, "2.1.0"))
+        {
+          log_error ("error: GnuPG agent version \"%s\" is too old. ",
+                     agent_version);
+          log_error ("Please install an updated GnuPG agent.\n");
+          log_error ("migration aborted\n");
+          xfree (agent_version);
+          goto leave;
+        }
+      xfree (agent_version);
+    }
+  else
+    {
+      log_error ("error: GnuPG agent unusable. "
+                 "Please check that a GnuPG agent can be started.\n");
+      log_error ("migration aborted\n");
+      goto leave;
+    }
+
   log_info ("porting secret keys from '%s' to gpg-agent\n", secring);
   if (!import_old_secring (ctrl, secring))
     {