import of heimdal 0.3e

1 files changed, 241 insertions, 25 deletions

diff --git a/crypto/heimdal/lib/gssapi/unwrap.c b/crypto/heimdal/lib/gssapi/unwrap.c
index 210bab1..588517e 100644
--- a/crypto/heimdal/lib/gssapi/unwrap.c
+++ b/crypto/heimdal/lib/gssapi/unwrap.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997 - 2000 Kungliga Tekniska Högskolan
+ * Copyright (c) 1997 - 2001 Kungliga Tekniska Högskolan
  * (Royal Institute of Technology, Stockholm, Sweden). 
  * All rights reserved. 
  *
@@ -33,11 +33,11 @@
 
 #include "gssapi_locl.h"
 
-RCSID("$Id: unwrap.c,v 1.11 2000/01/25 23:13:38 assar Exp $");
+RCSID("$Id: unwrap.c,v 1.15 2001/01/29 02:08:58 assar Exp $");
 
 OM_uint32
 gss_krb5_getsomekey(const gss_ctx_id_t context_handle,
-		    des_cblock *key)
+		    krb5_keyblock **key)
 {
     /* XXX this is ugly, and probably incorrect... */
     krb5_keyblock *skey;
@@ -54,18 +54,19 @@ gss_krb5_getsomekey(const gss_ctx_id_t context_handle,
 			     &skey);
     if(skey == NULL)
 	return GSS_S_FAILURE;
-    memcpy(key, skey->keyvalue.data, sizeof(*key));
-    krb5_free_keyblock(gssapi_krb5_context, skey);
+    *key = skey;
     return 0;
 }
 
-OM_uint32 gss_unwrap
+static OM_uint32
+unwrap_des
            (OM_uint32 * minor_status,
             const gss_ctx_id_t context_handle,
             const gss_buffer_t input_message_buffer,
             gss_buffer_t output_message_buffer,
             int * conf_state,
-            gss_qop_t * qop_state
+            gss_qop_t * qop_state,
+	    krb5_keyblock *key
            )
 {
   u_char *p, *pad;
@@ -73,7 +74,7 @@ OM_uint32 gss_unwrap
   MD5_CTX md5;
   u_char hash[16], seq_data[8];
   des_key_schedule schedule;
-  des_cblock key;
+  des_cblock deskey;
   des_cblock zero;
   int i;
   int32_t seq_number;
@@ -109,19 +110,20 @@ OM_uint32 gss_unwrap
 
   if(cstate) {
       /* decrypt data */
-      gss_krb5_getsomekey(context_handle, &key);
-      for (i = 0; i < sizeof(key); ++i)
-	  key[i] ^= 0xf0;
-      des_set_key (&key, schedule);
+      memcpy (&deskey, key->keyvalue.data, sizeof(deskey));
+
+      for (i = 0; i < sizeof(deskey); ++i)
+	  deskey[i] ^= 0xf0;
+      des_set_key (&deskey, schedule);
       memset (&zero, 0, sizeof(zero));
-      des_cbc_encrypt ((const void *)p,
+      des_cbc_encrypt ((void *)p,
 		       (void *)p,
 		       input_message_buffer->length - len,
 		       schedule,
 		       &zero,
 		       DES_DECRYPT);
       
-      memset (key, 0, sizeof(key));
+      memset (deskey, 0, sizeof(deskey));
       memset (schedule, 0, sizeof(schedule));
   }
   /* check pad */
@@ -134,15 +136,15 @@ OM_uint32 gss_unwrap
   if (i != 0)
     return GSS_S_BAD_MIC;
 
-  MD5Init (&md5);
-  MD5Update (&md5, p - 24, 8);
-  MD5Update (&md5, p, input_message_buffer->length - len);
-  MD5Final (hash, &md5);
+  MD5_Init (&md5);
+  MD5_Update (&md5, p - 24, 8);
+  MD5_Update (&md5, p, input_message_buffer->length - len);
+  MD5_Final (hash, &md5);
 
   memset (&zero, 0, sizeof(zero));
-  gss_krb5_getsomekey(context_handle, &key);
-  des_set_key (&key, schedule);
-  des_cbc_cksum ((const void *)hash, (void *)hash, sizeof(hash),
+  memcpy (&deskey, key->keyvalue.data, sizeof(deskey));
+  des_set_key (&deskey, schedule);
+  des_cbc_cksum ((void *)hash, (void *)hash, sizeof(hash),
 		 schedule, &zero);
   if (memcmp (p - 8, hash, 8) != 0)
     return GSS_S_BAD_MIC;
@@ -161,11 +163,11 @@ OM_uint32 gss_unwrap
 	  4);
 
   p -= 16;
-  des_set_key (&key, schedule);
-  des_cbc_encrypt ((const void *)p, (void *)p, 8,
+  des_set_key (&deskey, schedule);
+  des_cbc_encrypt ((void *)p, (void *)p, 8,
 		   schedule, (des_cblock *)hash, DES_DECRYPT);
 
-  memset (key, 0, sizeof(key));
+  memset (deskey, 0, sizeof(deskey));
   memset (schedule, 0, sizeof(schedule));
 
   if (memcmp (p, seq_data, 8) != 0) {
@@ -179,7 +181,7 @@ OM_uint32 gss_unwrap
   /* copy out data */
 
   output_message_buffer->length = input_message_buffer->length
-    - len - 8 - padlength;
+    - len - padlength - 8;
   output_message_buffer->value  = malloc(output_message_buffer->length);
   if(output_message_buffer->length != 0 && output_message_buffer->value == NULL)
       return GSS_S_FAILURE;
@@ -188,3 +190,217 @@ OM_uint32 gss_unwrap
 	  output_message_buffer->length);
   return GSS_S_COMPLETE;
 }
+
+static OM_uint32
+unwrap_des3
+           (OM_uint32 * minor_status,
+            const gss_ctx_id_t context_handle,
+            const gss_buffer_t input_message_buffer,
+            gss_buffer_t output_message_buffer,
+            int * conf_state,
+            gss_qop_t * qop_state,
+	    krb5_keyblock *key
+           )
+{
+  u_char *p, *pad;
+  size_t len;
+  u_char seq[8];
+  krb5_data seq_data;
+  u_char cksum[20];
+  int i;
+  int32_t seq_number;
+  size_t padlength;
+  OM_uint32 ret;
+  int cstate;
+  krb5_crypto crypto;
+  Checksum csum;
+  int cmp;
+
+  p = input_message_buffer->value;
+  ret = gssapi_krb5_verify_header (&p,
+				   input_message_buffer->length,
+				   "\x02\x01");
+  if (ret)
+      return ret;
+
+  if (memcmp (p, "\x04\x00", 2) != 0) /* HMAC SHA1 DES3_KD */
+    return GSS_S_BAD_SIG;
+  p += 2;
+  if (memcmp (p, "\x02\x00", 2) == 0) {
+    cstate = 1;
+  } else if (memcmp (p, "\xff\xff", 2) == 0) {
+    cstate = 0;
+  } else
+    return GSS_S_BAD_MIC;
+  p += 2;
+  if(conf_state != NULL)
+    *conf_state = cstate;
+  if (memcmp (p, "\xff\xff", 2) != 0)
+    return GSS_S_DEFECTIVE_TOKEN;
+  p += 2;
+  p += 28;
+
+  len = p - (u_char *)input_message_buffer->value;
+
+  if(cstate) {
+      /* decrypt data */
+      krb5_data tmp;
+
+      ret = krb5_crypto_init(gssapi_krb5_context, key,
+			     ETYPE_DES3_CBC_NONE, &crypto);
+      if (ret) {
+	  *minor_status = ret;
+	  return GSS_S_FAILURE;
+      }
+      ret = krb5_decrypt(gssapi_krb5_context, crypto, KRB5_KU_USAGE_SEAL,
+			 p, input_message_buffer->length - len, &tmp);
+      krb5_crypto_destroy(gssapi_krb5_context, crypto);
+      if (ret) {
+	  *minor_status = ret;
+	  return GSS_S_FAILURE;
+      }
+      assert (tmp.length == input_message_buffer->length - len);
+
+      memcpy (p, tmp.data, tmp.length);
+      krb5_data_free(&tmp);
+  }
+  /* check pad */
+
+  pad = (u_char *)input_message_buffer->value + input_message_buffer->length - 1;
+  padlength = *pad;
+
+  for (i = padlength; i > 0 && *pad == padlength; i--, pad--)
+    ;
+  if (i != 0)
+    return GSS_S_BAD_MIC;
+
+  /* verify sequence number */
+  
+  krb5_auth_getremoteseqnumber (gssapi_krb5_context,
+				context_handle->auth_context,
+				&seq_number);
+  seq[0] = (seq_number >> 0)  & 0xFF;
+  seq[1] = (seq_number >> 8)  & 0xFF;
+  seq[2] = (seq_number >> 16) & 0xFF;
+  seq[3] = (seq_number >> 24) & 0xFF;
+  memset (seq + 4,
+	  (context_handle->more_flags & LOCAL) ? 0xFF : 0,
+	  4);
+
+  p -= 28;
+
+  ret = krb5_crypto_init(gssapi_krb5_context, key,
+			 ETYPE_DES3_CBC_NONE_IVEC, &crypto);
+  if (ret) {
+      *minor_status = ret;
+      return GSS_S_FAILURE;
+  }
+  {
+      des_cblock ivec;
+
+      memcpy(&ivec, p + 8, 8);
+      ret = krb5_decrypt_ivec (gssapi_krb5_context,
+			       crypto,
+			       KRB5_KU_USAGE_SEQ,
+			       p, 8, &seq_data,
+			       &ivec);
+  }
+  krb5_crypto_destroy (gssapi_krb5_context, crypto);
+  if (ret) {
+      *minor_status = ret;
+      return GSS_S_FAILURE;
+  }
+  if (seq_data.length != 8) {
+      krb5_data_free (&seq_data);
+      return GSS_S_BAD_MIC;
+  }
+
+  cmp = memcmp (seq, seq_data.data, seq_data.length);
+  krb5_data_free (&seq_data);
+  if (cmp != 0) {
+      return GSS_S_BAD_MIC;
+  }
+
+  krb5_auth_setremoteseqnumber (gssapi_krb5_context,
+				context_handle->auth_context,
+				++seq_number);
+
+  /* verify checksum */
+
+  memcpy (cksum, p + 8, 20);
+
+  memcpy (p + 20, p - 8, 8);
+
+  csum.cksumtype = CKSUMTYPE_HMAC_SHA1_DES3;
+  csum.checksum.length = 20;
+  csum.checksum.data   = cksum;
+
+  ret = krb5_crypto_init(gssapi_krb5_context, key, 0, &crypto);
+  if (ret) {
+      *minor_status = ret;
+      return GSS_S_FAILURE;
+  }
+
+  ret = krb5_verify_checksum (gssapi_krb5_context, crypto,
+			      KRB5_KU_USAGE_SIGN,
+			      p + 20,
+			      input_message_buffer->length - len + 8,
+			      &csum);
+  krb5_crypto_destroy (gssapi_krb5_context, crypto);
+  if (ret) {
+      *minor_status = ret;
+      return GSS_S_FAILURE;
+  }
+
+  /* copy out data */
+
+  output_message_buffer->length = input_message_buffer->length
+    - len - padlength - 8;
+  output_message_buffer->value  = malloc(output_message_buffer->length);
+  if(output_message_buffer->length != 0 && output_message_buffer->value == NULL)
+      return GSS_S_FAILURE;
+  memcpy (output_message_buffer->value,
+	  p + 36,
+	  output_message_buffer->length);
+  return GSS_S_COMPLETE;
+}
+
+OM_uint32 gss_unwrap
+           (OM_uint32 * minor_status,
+            const gss_ctx_id_t context_handle,
+            const gss_buffer_t input_message_buffer,
+            gss_buffer_t output_message_buffer,
+            int * conf_state,
+            gss_qop_t * qop_state
+           )
+{
+  krb5_keyblock *key;
+  OM_uint32 ret;
+  krb5_keytype keytype;
+
+  ret = gss_krb5_getsomekey(context_handle, &key);
+  if (ret) {
+      *minor_status = ret;
+      return GSS_S_FAILURE;
+  }
+  krb5_enctype_to_keytype (gssapi_krb5_context, key->keytype, &keytype);
+
+  switch (keytype) {
+  case KEYTYPE_DES :
+      ret = unwrap_des (minor_status, context_handle,
+			input_message_buffer, output_message_buffer,
+			conf_state, qop_state, key);
+      break;
+  case KEYTYPE_DES3 :
+      ret = unwrap_des3 (minor_status, context_handle,
+			 input_message_buffer, output_message_buffer,
+			 conf_state, qop_state, key);
+      break;
+  default :
+      *minor_status = KRB5_PROG_ETYPE_NOSUPP;
+      ret = GSS_S_FAILURE;
+      break;
+  }
+  krb5_free_keyblock (gssapi_krb5_context, key);
+  return ret;
+}