Added support for CKSUMTYPE_RSA_MD5_DES3

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@7734 dc483132-0cff-0310-8789-dd5450dbe970

diff --git a/src/lib/crypto/md5/ChangeLog b/src/lib/crypto/md5/ChangeLog
index 5577fe94c940725ac7367f6ab1f9f5dcec7f8df3..e7f991a38353e3fa11c382cc2543a2b7d3643fa5 100644 (file)
--- a/src/lib/crypto/md5/ChangeLog
+++ b/src/lib/crypto/md5/ChangeLog
@@ -1,3 +1,7 @@
+Thu Mar 28 09:50:58 1996  Richard Basch  <basch@lehman.com>
+
+       * md5crypto.c: Added support for CKSUMTYPE_RSA_MD5_DES3
+
 Sat Jan 27 00:56:38 1996  Mark Eichin  <eichin@cygnus.com>
 
        * t_cksum.c (main): use proper old-style definition.

diff --git a/src/lib/crypto/md5/md5crypto.c b/src/lib/crypto/md5/md5crypto.c
index 4689bfcf1ab83dd33694f5c8b8655bd89b4ab2df..d993c22b5db2688c8bd576802ea96f10597cb7b7 100644 (file)
--- a/src/lib/crypto/md5/md5crypto.c
+++ b/src/lib/crypto/md5/md5crypto.c
@@ -283,6 +283,63 @@ size_t seed_length;
        else 
            retval = KRB5KRB_AP_ERR_BAD_INTEGRITY;
     }
+    else if (cksum->checksum_type == CKSUMTYPE_RSA_MD5_DES3) {
+       if (cksum->length == (RSA_MD5_DES_CKSUM_LENGTH +
+                             RSA_MD5_DES_CONFOUND_LENGTH)) {
+           /*
+            * If we're verifying the correct implementation, then we have
+            * to do a little more work because we must decrypt the checksum
+            * because it contains the confounder in it.  So, figure out
+            * what our key variant is and then do it!
+            */
+
+           /* Set up the variant of the key (see RFC 1510 section 6.4.5) */
+           memset((char *) tmpkey, 0, sizeof(mit_des_cblock));
+           for (i=0; (i<seed_length) && (i<sizeof(mit_des_cblock)); i++)
+               tmpkey[i] = (((krb5_octet *) seed)[i]) ^ 0xf0;
+
+           keyblock.length = sizeof(mit_des3_cblock);
+           keyblock.contents = (krb5_octet *) tmpkey;
+           keyblock.enctype = ENCTYPE_DES3_CBC_MD5;
+
+           if ((retval = mit_des3_process_key(&eblock, &keyblock)))
+               return retval;
+           /* now decrypt it */
+           retval = mit_des3_cbc_encrypt((mit_des_cblock *)cksum->contents,
+                                         (mit_des_cblock *)&outtmp[0],
+                                         RSA_MD5_DES_CKSUM_LENGTH +
+                                         RSA_MD5_DES_CONFOUND_LENGTH,
+                                         (struct mit_des_ks_struct *)
+                                               eblock.priv,
+                                         ((struct mit_des_ks_struct *)
+                                               eblock.priv) + 1,
+                                         ((struct mit_des_ks_struct *)
+                                               eblock.priv) + 2,
+                                         keyblock.contents,
+                                         MIT_DES_DECRYPT);
+           if (retval) {
+               (void) mit_des_finish_key(&eblock);
+               return retval;
+           }
+           if (retval = mit_des_finish_key(&eblock))
+               return(retval);
+
+           /* Now that we have the decrypted checksum, try to regenerate it */
+           md5_calculate_cksum(&working,
+                               (krb5_pointer) outtmp,
+                               (size_t) RSA_MD5_DES_CONFOUND_LENGTH,
+                               in,
+                               in_length);
+
+           /* Compare the checksums */
+           if (memcmp((char *) &outtmp[RSA_MD5_DES_CONFOUND_LENGTH],
+                      (char *) &working.digest[0],
+                      RSA_MD5_DES_CKSUM_LENGTH))
+               retval = KRB5KRB_AP_ERR_BAD_INTEGRITY;
+       }
+       else 
+           retval = KRB5KRB_AP_ERR_BAD_INTEGRITY;
+    }
     else
        retval = KRB5KRB_AP_ERR_INAPP_CKSUM;