New gpgsm server option no-encrypt-to.

Add caching for symkey encryption.
Minor cleanups.

4 files changed, 48 insertions, 21 deletions

diff --git a/g10/ChangeLog b/g10/ChangeLog
index ef6817037..c3f62394a 100644
--- a/g10/ChangeLog
+++ b/g10/ChangeLog
@@ -1,3 +1,15 @@
+2009-05-18  Daiki Ueno  <[email protected]>  (wk)
+
+	* encode.c (encode_simple): Tell passphrase_to_dek to cache
+	the passphrase.
+	(setup_symkey): Ditto.
+	* mainproc.c (proc_symkey_enc): Tell passphrase_to_dek to cache
+	the passphrase.
+	(proc_encrypted): Ditto.
+	* passphrase.c (hash_passphrase): Remove arg CREATE.
+	(passphrase_to_dek): New mode 3 and 4 for caching passphrase for
+	symmetric encryption.
+
 2009-05-17  Werner Koch  <[email protected]>
 
 	* keygen.c (ask_algo): Add arg R_SUBKEY_ALGO.  Change return value
diff --git a/g10/encode.c b/g10/encode.c
index 10c638f89..0c7dc4e22 100644
--- a/g10/encode.c
+++ b/g10/encode.c
@@ -216,7 +216,7 @@ encode_simple( const char *filename, int mode, int use_seskey )
 	s2k->mode = RFC1991? 0:opt.s2k_mode;
 	s2k->hash_algo=S2K_DIGEST_ALGO;
 	cfx.dek = passphrase_to_dek( NULL, 0,
-				     default_cipher_algo(), s2k, 2,
+				     default_cipher_algo(), s2k, 4,
                                      NULL, &canceled);
 	if( !cfx.dek || !cfx.dek->keylen ) {
 	    rc = gpg_error (canceled? GPG_ERR_CANCELED:GPG_ERR_INV_PASSPHRASE);
@@ -397,7 +397,7 @@ setup_symkey(STRING2KEY **symkey_s2k,DEK **symkey_dek)
   (*symkey_s2k)->hash_algo = S2K_DIGEST_ALGO;
 
   *symkey_dek=passphrase_to_dek(NULL,0,opt.s2k_cipher_algo,
-				*symkey_s2k,2,NULL, &canceled);
+				*symkey_s2k, 4, NULL, &canceled);
   if(!*symkey_dek || !(*symkey_dek)->keylen)
     {
       xfree(*symkey_dek);
diff --git a/g10/mainproc.c b/g10/mainproc.c
index 84a9de5f1..beab791b9 100644
--- a/g10/mainproc.c
+++ b/g10/mainproc.c
@@ -311,7 +311,7 @@ proc_symkey_enc( CTX c, PACKET *pkt )
 	  }
 	else
 	  {
-	    c->dek = passphrase_to_dek (NULL, 0, algo, &enc->s2k, 0,
+	    c->dek = passphrase_to_dek (NULL, 0, algo, &enc->s2k, 3,
                                         NULL, NULL);
 	    if(c->dek)
 	      {
@@ -548,7 +548,7 @@ proc_encrypted( CTX c, PACKET *pkt )
 		log_info (_("assuming %s encrypted data\n"), "IDEA");
 	      }
 
-	    c->dek = passphrase_to_dek ( NULL, 0, algo, s2k, 0, NULL, NULL );
+	    c->dek = passphrase_to_dek ( NULL, 0, algo, s2k, 3, NULL, NULL );
 	    if (c->dek)
 	      c->dek->algo_info_printed = 1;
 	  }
diff --git a/g10/passphrase.c b/g10/passphrase.c
index f5d301398..84eedc211 100644
--- a/g10/passphrase.c
+++ b/g10/passphrase.c
@@ -50,11 +50,10 @@ static char *next_pw = NULL;
 static char *last_pw = NULL;
 
 
-/* Hash a passphrase using the supplied s2k. If create is true, create
-   a new salt or what else must be filled into the s2k for a new key.
-   always needs: dek->algo, s2k->mode, s2k->hash_algo.  */
+/* Hash a passphrase using the supplied s2k. 
+   Always needs: dek->algo, s2k->mode, s2k->hash_algo.  */
 static void
-hash_passphrase ( DEK *dek, char *pw, STRING2KEY *s2k, int create )
+hash_passphrase ( DEK *dek, char *pw, STRING2KEY *s2k)
 {
   gcry_md_hd_t md;
   int pass, i;
@@ -82,13 +81,6 @@ hash_passphrase ( DEK *dek, char *pw, STRING2KEY *s2k, int create )
           int len2 = pwlen + 8;
           ulong count = len2;
           
-          if ( create && !pass )
-            {
-              gcry_randomize (s2k->salt, 8, GCRY_STRONG_RANDOM);
-              if ( s2k->mode == 3 )
-                s2k->count = opt.s2k_count;
-	    }
-
           if ( s2k->mode == 3 )
             {
               count = S2K_DECODE_COUNT(s2k->count);
@@ -441,7 +433,9 @@ passphrase_clear_cache ( u32 *keyid, const char *cacheid, int algo )
 
    MODE 0:  Allow cached passphrase
         1:  Ignore cached passphrase 
-        2:  Ditto, but change the text to "repeat entry"
+        2:  Ditto, but create a new key
+        3:  Allow cached passphrase; use the S2K salt as the cache ID
+        4:  Ditto, but create a new key
 */
 DEK *
 passphrase_to_dek_ext (u32 *keyid, int pubkey_algo,
@@ -461,6 +455,7 @@ passphrase_to_dek_ext (u32 *keyid, int pubkey_algo,
   
   if ( !s2k )
     {
+      assert (mode != 3 && mode != 4);
       /* This is used for the old rfc1991 mode 
        * Note: This must match the code in encode.c with opt.rfc1991 set */
       s2k = &help_s2k;
@@ -468,6 +463,15 @@ passphrase_to_dek_ext (u32 *keyid, int pubkey_algo,
       s2k->hash_algo = S2K_DIGEST_ALGO;
     }
 
+  /* Create a new salt or what else to be filled into the s2k for a
+     new key.  */
+  if ((mode == 2 || mode == 4) && (s2k->mode == 1 || s2k->mode == 3))
+    {
+      gcry_randomize (s2k->salt, 8, GCRY_STRONG_RANDOM);
+      if ( s2k->mode == 3 )
+        s2k->count = opt.s2k_count;
+    }
+
   /* If we do not have a passphrase available in NEXT_PW and status
      information are request, we print them now. */
   if ( !next_pw && is_status_enabled() ) 
@@ -565,10 +569,21 @@ passphrase_to_dek_ext (u32 *keyid, int pubkey_algo,
     }
   else 
     {
+      char *cacheid = NULL;
+      char buf[1+16+1];
+
+      if ((mode == 3 || mode == 4) && (s2k->mode == 1 || s2k->mode == 3))
+	{
+	  memset (buf, 0, sizeof buf);
+	  *buf = 'S';
+	  bin2hex (s2k->salt, 8, buf + 1);
+          cacheid = buf;
+	}
+
       /* Divert to the gpg-agent. */
-      pw = passphrase_get ( keyid, mode == 2, NULL,
-                            mode == 2? opt.passwd_repeat: 0,
-                            tryagain_text, custdesc, custprompt, canceled);
+      pw = passphrase_get (keyid, mode == 2, cacheid,
+                           (mode == 2 || mode == 4)? opt.passwd_repeat : 0,
+                           tryagain_text, custdesc, custprompt, canceled);
       if (*canceled)
         {
           xfree (pw);
@@ -585,10 +600,10 @@ passphrase_to_dek_ext (u32 *keyid, int pubkey_algo,
      get_last_passphrase(). */
   dek = xmalloc_secure_clear ( sizeof *dek );
   dek->algo = cipher_algo;
-  if ( !*pw && mode == 2 )
+  if ( !*pw && (mode == 2 || mode == 4))
     dek->keylen = 0;
   else
-    hash_passphrase( dek, pw, s2k, mode==2 );
+    hash_passphrase (dek, pw, s2k);
   xfree(last_pw);
   last_pw = pw;
   return dek;