From 66830aa4ab0c36b601581afe16a2f2f622cb0953 Mon Sep 17 00:00:00 2001
From: Johan Danielsson <joda@pdc.kth.se>
Date: Mon, 7 Jul 1997 00:51:50 +0000
Subject: [PATCH] Implement des-cbc-crc, and des-cbc-md5 in separate function.

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@1987 ec53bebd-3082-4978-b11e-865c3cabbd6b
---
 lib/krb5/decrypt.c | 88 ++++++++++++++++++++++++++++++++++------------
 1 file changed, 66 insertions(+), 22 deletions(-)

diff --git a/lib/krb5/decrypt.c b/lib/krb5/decrypt.c
index 234cdd01e..1e69cd3c2 100644
--- a/lib/krb5/decrypt.c
+++ b/lib/krb5/decrypt.c
@@ -1,35 +1,79 @@
 #include <krb5_locl.h>
 #include "crc.h"
+#include <md5.h>
 
 RCSID("$Id$");
 
+krb5_error_code
+krb5_des_cbc_decrypt(krb5_context context,
+		     void *ptr,
+		     size_t len,
+		     int etype,
+		     const krb5_keyblock *keyblock,
+		     krb5_data *result)
+{
+    u_char *p = (u_char *)ptr;
+    size_t offset;
+    des_cblock key;
+    des_key_schedule schedule;
+
+    memcpy (&key, keyblock->keyvalue.data, sizeof(key));
+    des_set_key (&key, schedule);
+    des_cbc_encrypt ((des_cblock *)ptr, (des_cblock *)ptr, len, 
+		     schedule, &key, DES_DECRYPT);
+    switch(etype){
+    case ETYPE_DES_CBC_MD5:
+	{
+	    struct md5 m;
+	    u_int32_t his_checksum[4];
+	    u_int32_t my_checksum[4];
+	    memcpy(his_checksum, p + 8, 16);
+	    memset(p + 8, 0, 16);
+	    md5init(&m);
+	    md5_update (&m, ptr, len);
+	    md5_finito(&m, my_checksum);
+	    if(memcmp(his_checksum, my_checksum, 16))
+		return KRB5KRB_AP_ERR_BAD_INTEGRITY;
+	    offset = 24;
+	}
+    break;
+	
+    case ETYPE_DES_CBC_CRC:
+	{
+	    u_int32_t my_crc, her_crc;
+	    her_crc = (p[11] << 24) | (p[10] << 16) | 
+		      (p[9] << 8) | (p[8] << 0);
+	    memset (p + 8, 0, sizeof(her_crc));
+	    crc_init_table ();
+	    my_crc = crc_update (ptr, len, 0);
+	    if (my_crc != her_crc)
+		return KRB5KRB_AP_ERR_BAD_INTEGRITY;
+	    offset = 12;
+	}
+    break;
+    default:
+	return KRB5_PROG_ETYPE_NOSUPP;
+    }
+    result->length = len - offset;
+    result->data = malloc(result->length);
+    if (result->data == NULL)
+	return ENOMEM;
+    memcpy(result->data, p + 12, result->length);
+    return 0;
+}
+		    
+
 krb5_error_code
 krb5_decrypt (krb5_context context,
 	      void *ptr,
 	      size_t len,
+	      int etype,
 	      const krb5_keyblock *keyblock,
 	      krb5_data *result)
 {
-  u_char *p = (u_char *)ptr;
-  u_int32_t my_crc, her_crc;
-  des_cblock key;
-  des_key_schedule schedule;
-
-  memcpy (&key, keyblock->keyvalue.data, sizeof(key));
-  des_set_key (&key, schedule);
-  des_cbc_encrypt ((des_cblock *)ptr, (des_cblock *)ptr, len, 
-		   schedule, &key, DES_DECRYPT);
-
-  her_crc = (p[11] << 24) | (p[10] << 16) | (p[9] << 8) | (p[8] << 0);
-  memset (p + 8, 0, sizeof(her_crc));
-  crc_init_table ();
-  my_crc = crc_update (ptr, len, 0);
-  if (my_crc != her_crc)
-    return KRB5KRB_AP_ERR_BAD_INTEGRITY;
-  result->length = len - 12;
-  result->data = malloc(result->length);
-  if (result->data == NULL)
-    return ENOMEM;
-  memcpy (result->data, (u_char *)ptr + 12, result->length);
-  return 0;
+    switch(etype){
+    case ETYPE_DES_CBC_CRC:
+	return des_cbc_crc_decrypt(context, ptr, len, etype, keyblock, result);
+    }
+    return KRB5_PROG_ETYPE_NOSUPP;
 }