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re-organize and add 3DES code

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git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@9004 ec53bebd-3082-4978-b11e-865c3cabbd6b
This commit is contained in:
Assar Westerlund
2000-08-27 04:26:12 +00:00
parent 2662f930e7
commit 8180bca1d4
6 changed files with 1288 additions and 106 deletions
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242
lib/gssapi/unwrap.c
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@@ -37,7 +37,7 @@ RCSID("$Id$");
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;
@@ -109,10 +110,11 @@ 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 ((void *)p,
(void *)p,
@@ -121,7 +123,7 @@ OM_uint32 gss_unwrap
&zero,
DES_DECRYPT);
memset (key, 0, sizeof(key));
memset (deskey, 0, sizeof(deskey));
memset (schedule, 0, sizeof(schedule));
}
/* check pad */
@@ -140,8 +142,8 @@ OM_uint32 gss_unwrap
MD5Final (hash, &md5);
memset (&zero, 0, sizeof(zero));
gss_krb5_getsomekey(context_handle, &key);
des_set_key (&key, schedule);
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)
@@ -161,11 +163,11 @@ OM_uint32 gss_unwrap
4);
p -= 16;
des_set_key (&key, schedule);
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 +190,211 @@ 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, &crypto);
if (ret) {
*minor_status = ret;
return GSS_S_FAILURE;
}
ret = krb5_decrypt (gssapi_krb5_context,
crypto,
KRB5_KU_USAGE_SEQ,
p, 8, &seq_data);
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;
}