do encrypt and add sequence number

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@1918 ec53bebd-3082-4978-b11e-865c3cabbd6b
This commit is contained in:
Assar Westerlund
1997-06-16 03:46:04 +00:00
parent 20bbef706b
commit d41212baa9
4 changed files with 262 additions and 28 deletions

View File

@@ -1,6 +1,4 @@
#include "gssapi_locl.h"
#include <des.h>
#include <md5.h>
RCSID("$Id$");
@@ -13,13 +11,16 @@ OM_uint32 gss_unwrap
gss_qop_t * qop_state
)
{
u_char *p;
u_char *p, *pad;
size_t len;
struct md5 md5;
u_char hash[16];
u_char hash[16], seq_data[8];
des_key_schedule schedule;
des_cblock key;
des_cblock zero;
int i;
int32_t seq_number;
size_t padlength;
p = input_message_buffer->value;
len = GSS_KRB5_MECHANISM->length + 28;
@@ -36,7 +37,7 @@ OM_uint32 gss_unwrap
if (memcmp (p, "\x00\x00", 2) != 0)
return GSS_S_BAD_SIG;
p += 2;
if (memcmp (p, "\xff\xff", 2) != 0)
if (memcmp (p, "\x0\x00", 2) != 0)
return GSS_S_BAD_MIC;
p += 2;
if (memcmp (p, "\xff\xff", 2) != 0)
@@ -58,12 +59,73 @@ OM_uint32 gss_unwrap
if (memcmp (p - 8, hash, 8) != 0)
return GSS_S_BAD_MIC;
output_message_buffer->length = input_message_buffer->length - len;
/* verify sequence number */
krb5_auth_getremoteseqnumber (gssapi_krb5_context,
context_handle->auth_context,
&seq_number);
seq_data[0] = (seq_number >> 0) & 0xFF;
seq_data[1] = (seq_number >> 8) & 0xFF;
seq_data[2] = (seq_number >> 16) & 0xFF;
seq_data[3] = (seq_number >> 24) & 0xFF;
memset (seq_data + 4,
(context_handle->more_flags & LOCAL) ? 0 : 0xFF,
4);
p -= 16;
des_set_key (&key, schedule);
des_cbc_encrypt (p, p, 8, schedule, hash, DES_DECRYPT);
memset (key, 0, sizeof(key));
memset (schedule, 0, sizeof(schedule));
if (memcmp (p, seq_data, 8) != 0) {
return GSS_S_BAD_MIC;
}
krb5_auth_setremoteseqnumber (gssapi_krb5_context,
context_handle->auth_context,
++seq_number);
/* decrypt data */
p += 16;
memset (&zero, 0, sizeof(zero));
memcpy (&key, context_handle->auth_context->key.keyvalue.data,
sizeof(key));
for (i = 0; i < sizeof(key); ++i)
key[i] ^= 0xf0;
des_set_key (&key, schedule);
des_cbc_encrypt ((des_cblock *)p,
(des_cblock *)p,
input_message_buffer->length - len,
schedule,
&zero,
DES_DECRYPT);
memset (key, 0, sizeof(key));
memset (schedule, 0, sizeof(schedule));
/* check pad */
pad = (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;
/* copy out data */
output_message_buffer->length = input_message_buffer->length
- len - 8 - padlength;
output_message_buffer->value = malloc(output_message_buffer->length);
if(output_message_buffer->value == NULL)
return GSS_S_FAILURE;
memcpy (output_message_buffer->value,
p,
p + 8,
output_message_buffer->length);
return GSS_S_COMPLETE;
}