Detect and bailo out on double plaintext messages.

NEWS

@@ -1,3 +1,9 @@
+Noteworthy changes in version 1.1.4
+------------------------------------------------
+
+ * Detect and bail out on double plaintext messages.
+
+
 Noteworthy changes in version 1.1.3 (2007-01-29)
 ------------------------------------------------
 

gpgme/ChangeLog

@@ -1,3 +1,11 @@
+2007-02-26  Werner Koch  <wk@g10code.com>
+
+	* verify.c (op_data_t): New element PLAINTEXT_SEEN.
+	(_gpgme_verify_status_handler): Return an error if more than one
+	plaintext has been seen.
+	(parse_error): New arg SET_STATUS. Also detect it based on an
+	ERROR status (gpg > 1.4.6).
+
 2007-01-26  Werner Koch  <wk@g10code.com>
 
 	* w32-io.c (build_commandline): Fixed stupid quoting bug.

gpgme/gpgme.h

@@ -72,7 +72,7 @@ extern "C" {
    AM_PATH_GPGME macro) check that this header matches the installed
    library.  Warning: Do not edit the next line.  configure will do
    that for you!  */
-#define GPGME_VERSION "1.1.3-cvs1202"
+#define GPGME_VERSION "1.1.3"
 
 
 

gpgme/verify.c

@@ -40,6 +40,7 @@ typedef struct
   gpgme_signature_t current_sig;
   int did_prepare_new_sig;
   int only_newsig_seen;
+  int plaintext_seen;
 } *op_data_t;
 
 
@@ -549,8 +550,11 @@ parse_trust (gpgme_signature_t sig, gpgme_status_code_t code, char *args)
 }
 
 
+/* Parse an error status line and if SET_STATUS is true update the
+   result status as appropriate.  With SET_STATUS being false, only
+   check for an error.  */
 static gpgme_error_t
-parse_error (gpgme_signature_t sig, char *args)
+parse_error (gpgme_signature_t sig, char *args, int set_status)
 {
   gpgme_error_t err;
   char *where = strchr (args, ' ');
@@ -572,7 +576,16 @@ parse_error (gpgme_signature_t sig, char *args)
 
   err = _gpgme_map_gnupg_error (which);
 
-  if (!strcmp (where, "verify.findkey"))
+  if (!strcmp (where, "proc_pkt.plaintext")
+      && gpg_err_code (err) == GPG_ERR_BAD_DATA)
+    {
+      /* This indicates a double plaintext.  The only solid way to
+         handle this is by failing the oepration.  */
+      return gpg_error (GPG_ERR_BAD_DATA);
+    }
+  else if (!set_status)
+    ;
+  else if (!strcmp (where, "verify.findkey"))
     sig->status = err;
   else if (!strcmp (where, "verify.keyusage")
 	   && gpg_err_code (err) == GPG_ERR_WRONG_KEY_USAGE)
@@ -670,9 +683,9 @@ _gpgme_verify_status_handler (void *priv, gpgme_status_code_t code, char *args)
 
     case GPGME_STATUS_ERROR:
       opd->only_newsig_seen = 0;
-      /* The error status is informational, so we don't return an
+      /* Some  error stati are informational, so we don't return an
          error code if we are not ready to process this status.  */
-      return sig ? parse_error (sig, args) : 0;
+      return parse_error (sig, args, !!sig );
 
     case GPGME_STATUS_EOF:
       if (sig && !opd->did_prepare_new_sig)
@@ -703,6 +716,8 @@ _gpgme_verify_status_handler (void *priv, gpgme_status_code_t code, char *args)
       break;
 
     case GPGME_STATUS_PLAINTEXT:
+      if (++opd->only_newsig_seen > 1)
+        return gpg_error (GPG_ERR_BAD_DATA);
       err = _gpgme_parse_plaintext (args, &opd->result.file_name);
       if (err)
 	return err;
@@ -816,7 +831,8 @@ gpgme_get_sig_key (gpgme_ctx_t ctx, int idx, gpgme_key_t *r_key)
    successful verify operation in R_STAT (if non-null).  The creation
    time stamp of the signature is returned in R_CREATED (if non-null).
    The function returns a string containing the fingerprint.  */
-const char *gpgme_get_sig_status (gpgme_ctx_t ctx, int idx,
+const char *
+gpgme_get_sig_status (gpgme_ctx_t ctx, int idx,
                       _gpgme_sig_stat_t *r_stat, time_t *r_created)
 {
   gpgme_verify_result_t result;
@@ -876,7 +892,8 @@ const char *gpgme_get_sig_status (gpgme_ctx_t ctx, int idx,
    number of the signature after a successful verify operation.  WHAT
    is an attribute where GPGME_ATTR_EXPIRE is probably the most useful
    one.  WHATIDX is to be passed as 0 for most attributes . */
-unsigned long gpgme_get_sig_ulong_attr (gpgme_ctx_t ctx, int idx,
+unsigned long 
+gpgme_get_sig_ulong_attr (gpgme_ctx_t ctx, int idx,
                           _gpgme_attr_t what, int whatidx)
 {
   gpgme_verify_result_t result;
@@ -939,7 +956,8 @@ unsigned long gpgme_get_sig_ulong_attr (gpgme_ctx_t ctx, int idx,
 }
 
 
-const char *gpgme_get_sig_string_attr (gpgme_ctx_t ctx, int idx,
+const char *
+gpgme_get_sig_string_attr (gpgme_ctx_t ctx, int idx,
                            _gpgme_attr_t what, int whatidx)
 {
   gpgme_verify_result_t result;

tests/ChangeLog

@@ -1,3 +1,8 @@
+2007-02-26  Werner Koch  <wk@g10code.com>
+
+	* gpg/t-verify.c (double_plaintext_sig): New.
+	(main): Check it.
+
 2006-12-02  Marcus Brinkmann  <marcus@g10code.de>
 
 	* gpgsm/t-keylist.c (main): Skip unknown keys.  Newer versions of

tests/gpg/t-verify.c

@@ -76,6 +76,20 @@ static const char test_sig2[] =
 "=Crq6\n"
 "-----END PGP MESSAGE-----\n";
 
+/* A message with a prepended but unsigned plaintext packet. */
+static const char double_plaintext_sig[] = 
+"-----BEGIN PGP MESSAGE-----\n"
+"\n"
+"rDRiCmZvb2Jhci50eHRF4pxNVGhpcyBpcyBteSBzbmVha3kgcGxhaW50ZXh0IG1l\n"
+"c3NhZ2UKowGbwMvMwCSoW1RzPCOz3IRxTWISa6JebnG666MFD1wzSzJSixQ81XMV\n"
+"UlITUxTyixRyKxXKE0uSMxQyEosVikvyCwpSU/S4FNCArq6Ce1F+aXJGvoJvYlGF\n"
+"erFCTmJxiUJ5flFKMVeHGwuDIBMDGysTyA4GLk4BmO036xgWzMgzt9V85jCtfDFn\n"
+"UqVooWlGXHwNw/xg/fVzt9VNbtjtJ/fhUqYo0/LyCGEA\n"
+"=6+AK\n"
+"-----END PGP MESSAGE-----\n";
+
+
+
 
 static void
 check_result (gpgme_verify_result_t result, unsigned int summary, char *fpr,
@@ -235,6 +249,23 @@ main (int argc, char *argv[])
   check_result (result, 0, "A0FF4590BB6122EDEF6E3C542D727CC768697734",
 		GPG_ERR_NO_ERROR, 0);
 
+
+  /* Checking an invalid message.  */
+  gpgme_data_release (sig);
+  gpgme_data_release (text);
+  err = gpgme_data_new_from_mem (&sig, double_plaintext_sig,
+                                 strlen (double_plaintext_sig), 0);
+  fail_if_err (err);
+  err = gpgme_data_new (&text);
+  fail_if_err (err);
+  err = gpgme_op_verify (ctx, sig, NULL, text);
+  if (gpg_err_code (err) != GPG_ERR_BAD_DATA)
+    {
+      fprintf (stderr, "%s:%i: Double plaintext message not detected\n",
+	       __FILE__, __LINE__);
+      exit (1);
+    }
+
   gpgme_data_release (sig);
   gpgme_data_release (text);
   gpgme_release (ctx);