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heimdal/lib/gssapi/krb5/arcfour.c
Nicolas Williams 5f63215d0d Always perform == or != operation on cmp function result 
Although not required to address bad code generation in
some versions of gcc 9 and 10, a coding style that requires
explicit comparison of the result to zero before use is
both clearer and would have avoided the generation of bad
code.

This change converts all use of cmp function usage from

```
    if (strcmp(a, b) || !strcmp(c, d)) ...
```

to

```
    if (strcmp(a, b) != 0 || strcmp(c, d)) == 0
```

for all C library cmp functions and related:

 - strcmp(), strncmp()
 - strcasecmp(), strncasecmp()
 - stricmp(), strnicmp()
 - memcmp()

Change-Id: Ic60c15e1e3a07e4faaf10648eefe3adae2543188
2021-11-24 22:30:44 -05:00

1384 lines
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/*
* Copyright (c) 2003 - 2006 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "gsskrb5_locl.h"
/*
* Implements draft-brezak-win2k-krb-rc4-hmac-04.txt
*
* The arcfour message have the following formats:
*
* MIC token
* TOK_ID[2] = 01 01
* SGN_ALG[2] = 11 00
* Filler[4]
* SND_SEQ[8]
* SGN_CKSUM[8]
*
* WRAP token
* TOK_ID[2] = 02 01
* SGN_ALG[2];
* SEAL_ALG[2]
* Filler[2]
* SND_SEQ[2]
* SGN_CKSUM[8]
* Confounder[8]
*/
/*
* WRAP in DCE-style have a fixed size header, the oid and length over
* the WRAP header is a total of
* GSS_ARCFOUR_WRAP_TOKEN_DCE_DER_HEADER_SIZE +
* GSS_ARCFOUR_WRAP_TOKEN_SIZE byte (ie total of 45 bytes overhead,
* remember the 2 bytes from APPL [0] SEQ).
*/
#define GSS_ARCFOUR_WRAP_TOKEN_SIZE 32
#define GSS_ARCFOUR_WRAP_TOKEN_DCE_DER_HEADER_SIZE 13
static krb5_error_code
arcfour_mic_key(krb5_context context, krb5_keyblock *key,
const void *cksum_data, size_t cksum_size,
void *key6_data, size_t key6_size)
{
krb5_error_code ret;
Checksum cksum_k5;
krb5_keyblock key5;
char k5_data[16];
Checksum cksum_k6;
char T[4];
memset(T, 0, 4);
cksum_k5.checksum.data = k5_data;
cksum_k5.checksum.length = sizeof(k5_data);
if (key->keytype == KRB5_ENCTYPE_ARCFOUR_HMAC_MD5_56) {
char L40[14] = "fortybits";
memcpy(L40 + 10, T, sizeof(T));
ret = krb5_hmac(context, CKSUMTYPE_RSA_MD5,
L40, 14, 0, key, &cksum_k5);
memset(&k5_data[7], 0xAB, 9);
} else {
ret = krb5_hmac(context, CKSUMTYPE_RSA_MD5,
T, 4, 0, key, &cksum_k5);
}
if (ret)
return ret;
key5.keytype = KRB5_ENCTYPE_ARCFOUR_HMAC_MD5;
key5.keyvalue = cksum_k5.checksum;
cksum_k6.checksum.data = key6_data;
cksum_k6.checksum.length = key6_size;
return krb5_hmac(context, CKSUMTYPE_RSA_MD5,
cksum_data, cksum_size, 0, &key5, &cksum_k6);
}
static krb5_error_code
arcfour_mic_cksum_iov(krb5_context context,
krb5_keyblock *key, unsigned usage,
u_char *sgn_cksum, size_t sgn_cksum_sz,
const u_char *v1, size_t l1,
const void *v2, size_t l2,
const gss_iov_buffer_desc *iov,
int iov_count,
const gss_iov_buffer_desc *padding)
{
Checksum CKSUM;
u_char *ptr;
size_t len;
size_t ofs = 0;
int i;
krb5_crypto crypto;
krb5_error_code ret;
assert(sgn_cksum_sz == 8);
len = l1 + l2;
for (i=0; i < iov_count; i++) {
switch (GSS_IOV_BUFFER_TYPE(iov[i].type)) {
case GSS_IOV_BUFFER_TYPE_DATA:
case GSS_IOV_BUFFER_TYPE_SIGN_ONLY:
break;
default:
continue;
}
len += iov[i].buffer.length;
}
if (padding) {
len += padding->buffer.length;
}
ptr = malloc(len);
if (ptr == NULL)
return ENOMEM;
memcpy(ptr + ofs, v1, l1);
ofs += l1;
memcpy(ptr + ofs, v2, l2);
ofs += l2;
for (i=0; i < iov_count; i++) {
switch (GSS_IOV_BUFFER_TYPE(iov[i].type)) {
case GSS_IOV_BUFFER_TYPE_DATA:
case GSS_IOV_BUFFER_TYPE_SIGN_ONLY:
break;
default:
continue;
}
memcpy(ptr + ofs,
iov[i].buffer.value,
iov[i].buffer.length);
ofs += iov[i].buffer.length;
}
if (padding) {
memcpy(ptr + ofs,
padding->buffer.value,
padding->buffer.length);
ofs += padding->buffer.length;
}
ret = krb5_crypto_init(context, key, 0, &crypto);
if (ret) {
free(ptr);
return ret;
}
ret = krb5_create_checksum(context,
crypto,
usage,
0,
ptr, len,
&CKSUM);
memset(ptr, 0, len);
free(ptr);
if (ret == 0) {
memcpy(sgn_cksum, CKSUM.checksum.data, sgn_cksum_sz);
free_Checksum(&CKSUM);
}
krb5_crypto_destroy(context, crypto);
return ret;
}
static krb5_error_code
arcfour_mic_cksum(krb5_context context,
krb5_keyblock *key, unsigned usage,
u_char *sgn_cksum, size_t sgn_cksum_sz,
const u_char *v1, size_t l1,
const void *v2, size_t l2,
const void *v3, size_t l3)
{
gss_iov_buffer_desc iov;
iov.type = GSS_IOV_BUFFER_TYPE_SIGN_ONLY;
iov.buffer.value = rk_UNCONST(v3);
iov.buffer.length = l3;
return arcfour_mic_cksum_iov(context, key, usage,
sgn_cksum, sgn_cksum_sz,
v1, l1, v2, l2,
&iov, 1, NULL);
}
OM_uint32
_gssapi_get_mic_arcfour(OM_uint32 * minor_status,
const gsskrb5_ctx context_handle,
krb5_context context,
gss_qop_t qop_req,
const gss_buffer_t message_buffer,
gss_buffer_t message_token,
krb5_keyblock *key)
{
krb5_error_code ret;
int32_t seq_number;
size_t len, total_len;
u_char k6_data[16], *p0, *p;
EVP_CIPHER_CTX rc4_key;
_gsskrb5_encap_length (22, &len, &total_len, GSS_KRB5_MECHANISM);
message_token->length = total_len;
message_token->value = malloc (total_len);
if (message_token->value == NULL) {
*minor_status = ENOMEM;
return GSS_S_FAILURE;
}
p0 = _gssapi_make_mech_header(message_token->value,
len,
GSS_KRB5_MECHANISM);
p = p0;
*p++ = 0x01; /* TOK_ID */
*p++ = 0x01;
*p++ = 0x11; /* SGN_ALG */
*p++ = 0x00;
*p++ = 0xff; /* Filler */
*p++ = 0xff;
*p++ = 0xff;
*p++ = 0xff;
p = NULL;
ret = arcfour_mic_cksum(context,
key, KRB5_KU_USAGE_SIGN,
p0 + 16, 8, /* SGN_CKSUM */
p0, 8, /* TOK_ID, SGN_ALG, Filer */
message_buffer->value, message_buffer->length,
NULL, 0);
if (ret) {
_gsskrb5_release_buffer(minor_status, message_token);
*minor_status = ret;
return GSS_S_FAILURE;
}
ret = arcfour_mic_key(context, key,
p0 + 16, 8, /* SGN_CKSUM */
k6_data, sizeof(k6_data));
if (ret) {
_gsskrb5_release_buffer(minor_status, message_token);
*minor_status = ret;
return GSS_S_FAILURE;
}
HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
krb5_auth_con_getlocalseqnumber (context,
context_handle->auth_context,
&seq_number);
p = p0 + 8; /* SND_SEQ */
_gsskrb5_encode_be_om_uint32(seq_number, p);
krb5_auth_con_setlocalseqnumber (context,
context_handle->auth_context,
++seq_number);
HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
memset (p + 4, (context_handle->more_flags & LOCAL) ? 0 : 0xff, 4);
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, k6_data, NULL, 1);
EVP_Cipher(&rc4_key, p, p, 8);
EVP_CIPHER_CTX_cleanup(&rc4_key);
memset_s(k6_data, sizeof(k6_data), 0, sizeof(k6_data));
*minor_status = 0;
return GSS_S_COMPLETE;
}
OM_uint32
_gssapi_verify_mic_arcfour(OM_uint32 * minor_status,
const gsskrb5_ctx context_handle,
krb5_context context,
const gss_buffer_t message_buffer,
const gss_buffer_t token_buffer,
gss_qop_t * qop_state,
krb5_keyblock *key,
const char *type)
{
krb5_error_code ret;
uint32_t seq_number;
OM_uint32 omret;
u_char SND_SEQ[8], cksum_data[8], *p;
char k6_data[16];
int cmp;
if (qop_state)
*qop_state = 0;
p = token_buffer->value;
omret = _gsskrb5_verify_header (&p,
token_buffer->length,
type,
GSS_KRB5_MECHANISM);
if (omret)
return omret;
if (memcmp(p, "\x11\x00", 2) != 0) /* SGN_ALG = HMAC MD5 ARCFOUR */
return GSS_S_BAD_SIG;
p += 2;
if (memcmp (p, "\xff\xff\xff\xff", 4) != 0)
return GSS_S_BAD_MIC;
p += 4;
ret = arcfour_mic_cksum(context,
key, KRB5_KU_USAGE_SIGN,
cksum_data, sizeof(cksum_data),
p - 8, 8,
message_buffer->value, message_buffer->length,
NULL, 0);
if (ret) {
*minor_status = ret;
return GSS_S_FAILURE;
}
ret = arcfour_mic_key(context, key,
cksum_data, sizeof(cksum_data),
k6_data, sizeof(k6_data));
if (ret) {
*minor_status = ret;
return GSS_S_FAILURE;
}
cmp = (ct_memcmp(cksum_data, p + 8, 8) != 0);
if (cmp) {
*minor_status = 0;
return GSS_S_BAD_MIC;
}
{
EVP_CIPHER_CTX rc4_key;
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, (void *)k6_data, NULL, 0);
EVP_Cipher(&rc4_key, SND_SEQ, p, 8);
EVP_CIPHER_CTX_cleanup(&rc4_key);
memset(k6_data, 0, sizeof(k6_data));
}
_gsskrb5_decode_be_om_uint32(SND_SEQ, &seq_number);
if (context_handle->more_flags & LOCAL)
cmp = (memcmp(&SND_SEQ[4], "\xff\xff\xff\xff", 4) != 0);
else
cmp = (memcmp(&SND_SEQ[4], "\x00\x00\x00\x00", 4) != 0);
memset_s(SND_SEQ, sizeof(SND_SEQ), 0, sizeof(SND_SEQ));
if (cmp != 0) {
*minor_status = 0;
return GSS_S_BAD_MIC;
}
HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
omret = _gssapi_msg_order_check(context_handle->order, seq_number);
HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
if (omret)
return omret;
*minor_status = 0;
return GSS_S_COMPLETE;
}
OM_uint32
_gssapi_wrap_arcfour(OM_uint32 * minor_status,
const gsskrb5_ctx context_handle,
krb5_context context,
int conf_req_flag,
gss_qop_t qop_req,
const gss_buffer_t input_message_buffer,
int * conf_state,
gss_buffer_t output_message_buffer,
krb5_keyblock *key)
{
u_char Klocaldata[16], k6_data[16], *p, *p0;
size_t len, total_len, datalen;
krb5_keyblock Klocal;
krb5_error_code ret;
int32_t seq_number;
if (conf_state)
*conf_state = 0;
datalen = input_message_buffer->length;
if (IS_DCE_STYLE(context_handle)) {
len = GSS_ARCFOUR_WRAP_TOKEN_SIZE;
_gssapi_encap_length(len, &len, &total_len, GSS_KRB5_MECHANISM);
total_len += datalen;
} else {
datalen += 1; /* padding */
len = datalen + GSS_ARCFOUR_WRAP_TOKEN_SIZE;
_gssapi_encap_length(len, &len, &total_len, GSS_KRB5_MECHANISM);
}
output_message_buffer->length = total_len;
output_message_buffer->value = malloc (total_len);
if (output_message_buffer->value == NULL) {
*minor_status = ENOMEM;
return GSS_S_FAILURE;
}
p0 = _gssapi_make_mech_header(output_message_buffer->value,
len,
GSS_KRB5_MECHANISM);
p = p0;
*p++ = 0x02; /* TOK_ID */
*p++ = 0x01;
*p++ = 0x11; /* SGN_ALG */
*p++ = 0x00;
if (conf_req_flag) {
*p++ = 0x10; /* SEAL_ALG */
*p++ = 0x00;
} else {
*p++ = 0xff; /* SEAL_ALG */
*p++ = 0xff;
}
*p++ = 0xff; /* Filler */
*p++ = 0xff;
p = NULL;
HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
krb5_auth_con_getlocalseqnumber (context,
context_handle->auth_context,
&seq_number);
_gsskrb5_encode_be_om_uint32(seq_number, p0 + 8);
krb5_auth_con_setlocalseqnumber (context,
context_handle->auth_context,
++seq_number);
HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
memset (p0 + 8 + 4,
(context_handle->more_flags & LOCAL) ? 0 : 0xff,
4);
krb5_generate_random_block(p0 + 24, 8); /* fill in Confounder */
/* p points to data */
p = p0 + GSS_ARCFOUR_WRAP_TOKEN_SIZE;
memcpy(p, input_message_buffer->value, input_message_buffer->length);
if (!IS_DCE_STYLE(context_handle))
p[input_message_buffer->length] = 1; /* padding */
ret = arcfour_mic_cksum(context,
key, KRB5_KU_USAGE_SEAL,
p0 + 16, 8, /* SGN_CKSUM */
p0, 8, /* TOK_ID, SGN_ALG, SEAL_ALG, Filler */
p0 + 24, 8, /* Confounder */
p0 + GSS_ARCFOUR_WRAP_TOKEN_SIZE,
datalen);
if (ret) {
*minor_status = ret;
_gsskrb5_release_buffer(minor_status, output_message_buffer);
return GSS_S_FAILURE;
}
{
int i;
Klocal.keytype = key->keytype;
Klocal.keyvalue.data = Klocaldata;
Klocal.keyvalue.length = sizeof(Klocaldata);
for (i = 0; i < 16; i++)
Klocaldata[i] = ((u_char *)key->keyvalue.data)[i] ^ 0xF0;
}
ret = arcfour_mic_key(context, &Klocal,
p0 + 8, 4, /* SND_SEQ */
k6_data, sizeof(k6_data));
memset_s(Klocaldata, sizeof(Klocaldata), 0, sizeof(Klocaldata));
if (ret) {
_gsskrb5_release_buffer(minor_status, output_message_buffer);
*minor_status = ret;
return GSS_S_FAILURE;
}
if(conf_req_flag) {
EVP_CIPHER_CTX rc4_key;
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, k6_data, NULL, 1);
EVP_Cipher(&rc4_key, p0 + 24, p0 + 24, 8 + datalen);
EVP_CIPHER_CTX_cleanup(&rc4_key);
}
memset(k6_data, 0, sizeof(k6_data));
ret = arcfour_mic_key(context, key,
p0 + 16, 8, /* SGN_CKSUM */
k6_data, sizeof(k6_data));
if (ret) {
_gsskrb5_release_buffer(minor_status, output_message_buffer);
*minor_status = ret;
return GSS_S_FAILURE;
}
{
EVP_CIPHER_CTX rc4_key;
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, k6_data, NULL, 1);
EVP_Cipher(&rc4_key, p0 + 8, p0 + 8 /* SND_SEQ */, 8);
EVP_CIPHER_CTX_cleanup(&rc4_key);
memset_s(k6_data, sizeof(k6_data), 0, sizeof(k6_data));
}
if (conf_state)
*conf_state = conf_req_flag;
*minor_status = 0;
return GSS_S_COMPLETE;
}
OM_uint32 _gssapi_unwrap_arcfour(OM_uint32 *minor_status,
const gsskrb5_ctx context_handle,
krb5_context context,
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 Klocaldata[16];
krb5_keyblock Klocal;
krb5_error_code ret;
uint32_t seq_number;
size_t datalen;
OM_uint32 omret;
u_char k6_data[16], SND_SEQ[8], Confounder[8];
u_char cksum_data[8];
u_char *p, *p0;
int cmp;
int conf_flag;
size_t padlen = 0, len;
if (conf_state)
*conf_state = 0;
if (qop_state)
*qop_state = 0;
p0 = input_message_buffer->value;
if (IS_DCE_STYLE(context_handle)) {
len = GSS_ARCFOUR_WRAP_TOKEN_SIZE +
GSS_ARCFOUR_WRAP_TOKEN_DCE_DER_HEADER_SIZE;
if (input_message_buffer->length < len)
return GSS_S_BAD_MECH;
} else {
len = input_message_buffer->length;
}
omret = _gssapi_verify_mech_header(&p0,
len,
GSS_KRB5_MECHANISM);
if (omret)
return omret;
/* length of mech header */
len = (p0 - (u_char *)input_message_buffer->value) +
GSS_ARCFOUR_WRAP_TOKEN_SIZE;
if (len > input_message_buffer->length)
return GSS_S_BAD_MECH;
/* length of data */
datalen = input_message_buffer->length - len;
p = p0;
if (memcmp(p, "\x02\x01", 2) != 0)
return GSS_S_BAD_SIG;
p += 2;
if (memcmp(p, "\x11\x00", 2) != 0) /* SGN_ALG = HMAC MD5 ARCFOUR */
return GSS_S_BAD_SIG;
p += 2;
if (memcmp (p, "\x10\x00", 2) == 0)
conf_flag = 1;
else if (memcmp (p, "\xff\xff", 2) == 0)
conf_flag = 0;
else
return GSS_S_BAD_SIG;
p += 2;
if (memcmp (p, "\xff\xff", 2) != 0)
return GSS_S_BAD_MIC;
p = NULL;
ret = arcfour_mic_key(context, key,
p0 + 16, 8, /* SGN_CKSUM */
k6_data, sizeof(k6_data));
if (ret) {
*minor_status = ret;
return GSS_S_FAILURE;
}
{
EVP_CIPHER_CTX rc4_key;
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, k6_data, NULL, 1);
EVP_Cipher(&rc4_key, SND_SEQ, p0 + 8, 8);
EVP_CIPHER_CTX_cleanup(&rc4_key);
memset_s(k6_data, sizeof(k6_data), 0, sizeof(k6_data));
}
_gsskrb5_decode_be_om_uint32(SND_SEQ, &seq_number);
if (context_handle->more_flags & LOCAL)
cmp = (memcmp(&SND_SEQ[4], "\xff\xff\xff\xff", 4) != 0);
else
cmp = (memcmp(&SND_SEQ[4], "\x00\x00\x00\x00", 4) != 0);
if (cmp != 0) {
*minor_status = 0;
return GSS_S_BAD_MIC;
}
{
int i;
Klocal.keytype = key->keytype;
Klocal.keyvalue.data = Klocaldata;
Klocal.keyvalue.length = sizeof(Klocaldata);
for (i = 0; i < 16; i++)
Klocaldata[i] = ((u_char *)key->keyvalue.data)[i] ^ 0xF0;
}
ret = arcfour_mic_key(context, &Klocal,
SND_SEQ, 4,
k6_data, sizeof(k6_data));
memset_s(Klocaldata, sizeof(Klocaldata), 0, sizeof(Klocaldata));
if (ret) {
*minor_status = ret;
return GSS_S_FAILURE;
}
output_message_buffer->value = malloc(datalen);
if (output_message_buffer->value == NULL) {
*minor_status = ENOMEM;
return GSS_S_FAILURE;
}
output_message_buffer->length = datalen;
if(conf_flag) {
EVP_CIPHER_CTX rc4_key;
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, k6_data, NULL, 1);
EVP_Cipher(&rc4_key, Confounder, p0 + 24, 8);
EVP_Cipher(&rc4_key, output_message_buffer->value, p0 + GSS_ARCFOUR_WRAP_TOKEN_SIZE, datalen);
EVP_CIPHER_CTX_cleanup(&rc4_key);
} else {
memcpy(Confounder, p0 + 24, 8); /* Confounder */
memcpy(output_message_buffer->value,
p0 + GSS_ARCFOUR_WRAP_TOKEN_SIZE,
datalen);
}
memset(k6_data, 0, sizeof(k6_data));
if (!IS_DCE_STYLE(context_handle)) {
ret = _gssapi_verify_pad(output_message_buffer, datalen, &padlen);
if (ret) {
_gsskrb5_release_buffer(minor_status, output_message_buffer);
*minor_status = 0;
return ret;
}
output_message_buffer->length -= padlen;
}
ret = arcfour_mic_cksum(context,
key, KRB5_KU_USAGE_SEAL,
cksum_data, sizeof(cksum_data),
p0, 8,
Confounder, sizeof(Confounder),
output_message_buffer->value,
output_message_buffer->length + padlen);
if (ret) {
_gsskrb5_release_buffer(minor_status, output_message_buffer);
*minor_status = ret;
return GSS_S_FAILURE;
}
cmp = ct_memcmp(cksum_data, p0 + 16, 8); /* SGN_CKSUM */
if (cmp) {
_gsskrb5_release_buffer(minor_status, output_message_buffer);
*minor_status = 0;
return GSS_S_BAD_MIC;
}
HEIMDAL_MUTEX_lock(&context_handle->ctx_id_mutex);
omret = _gssapi_msg_order_check(context_handle->order, seq_number);
HEIMDAL_MUTEX_unlock(&context_handle->ctx_id_mutex);
if (omret)
return omret;
if (conf_state)
*conf_state = conf_flag;
*minor_status = 0;
return GSS_S_COMPLETE;
}
static OM_uint32
max_wrap_length_arcfour(const gsskrb5_ctx ctx,
krb5_crypto crypto,
size_t input_length,
OM_uint32 *max_input_size)
{
/*
* if GSS_C_DCE_STYLE is in use:
* - we only need to encapsulate the WRAP token
* However, since this is a fixed since, we just
*/
if (IS_DCE_STYLE(ctx)) {
size_t len, total_len;
len = GSS_ARCFOUR_WRAP_TOKEN_SIZE;
_gssapi_encap_length(len, &len, &total_len, GSS_KRB5_MECHANISM);
if (input_length < len)
*max_input_size = 0;
else
*max_input_size = input_length - len;
} else {
size_t extrasize = GSS_ARCFOUR_WRAP_TOKEN_SIZE;
size_t blocksize = 8;
size_t len, total_len;
len = 8 + input_length + blocksize + extrasize;
_gsskrb5_encap_length(len, &len, &total_len, GSS_KRB5_MECHANISM);
total_len -= input_length; /* token length */
if (total_len < input_length) {
*max_input_size = (input_length - total_len);
(*max_input_size) &= (~(OM_uint32)(blocksize - 1));
} else {
*max_input_size = 0;
}
}
return GSS_S_COMPLETE;
}
OM_uint32
_gssapi_wrap_size_arcfour(OM_uint32 *minor_status,
const gsskrb5_ctx ctx,
krb5_context context,
int conf_req_flag,
gss_qop_t qop_req,
OM_uint32 req_output_size,
OM_uint32 *max_input_size,
krb5_keyblock *key)
{
krb5_error_code ret;
krb5_crypto crypto;
ret = krb5_crypto_init(context, key, 0, &crypto);
if (ret != 0) {
*minor_status = ret;
return GSS_S_FAILURE;
}
ret = max_wrap_length_arcfour(ctx, crypto,
req_output_size, max_input_size);
if (ret != 0) {
*minor_status = ret;
krb5_crypto_destroy(context, crypto);
return GSS_S_FAILURE;
}
krb5_crypto_destroy(context, crypto);
return GSS_S_COMPLETE;
}
OM_uint32
_gssapi_wrap_iov_length_arcfour(OM_uint32 *minor_status,
gsskrb5_ctx ctx,
krb5_context context,
int conf_req_flag,
gss_qop_t qop_req,
int *conf_state,
gss_iov_buffer_desc *iov,
int iov_count)
{
OM_uint32 major_status;
size_t data_len = 0;
int i;
gss_iov_buffer_desc *header = NULL;
gss_iov_buffer_desc *padding = NULL;
gss_iov_buffer_desc *trailer = NULL;
*minor_status = 0;
for (i = 0; i < iov_count; i++) {
switch(GSS_IOV_BUFFER_TYPE(iov[i].type)) {
case GSS_IOV_BUFFER_TYPE_EMPTY:
break;
case GSS_IOV_BUFFER_TYPE_DATA:
data_len += iov[i].buffer.length;
break;
case GSS_IOV_BUFFER_TYPE_HEADER:
if (header != NULL) {
*minor_status = EINVAL;
return GSS_S_FAILURE;
}
header = &iov[i];
break;
case GSS_IOV_BUFFER_TYPE_TRAILER:
if (trailer != NULL) {
*minor_status = EINVAL;
return GSS_S_FAILURE;
}
trailer = &iov[i];
break;
case GSS_IOV_BUFFER_TYPE_PADDING:
if (padding != NULL) {
*minor_status = EINVAL;
return GSS_S_FAILURE;
}
padding = &iov[i];
break;
case GSS_IOV_BUFFER_TYPE_SIGN_ONLY:
break;
default:
*minor_status = EINVAL;
return GSS_S_FAILURE;
}
}
major_status = _gk_verify_buffers(minor_status, ctx, header,
padding, trailer, FALSE);
if (major_status != GSS_S_COMPLETE) {
return major_status;
}
if (IS_DCE_STYLE(ctx)) {
size_t len = GSS_ARCFOUR_WRAP_TOKEN_SIZE;
size_t total_len;
_gssapi_encap_length(len, &len, &total_len, GSS_KRB5_MECHANISM);
header->buffer.length = total_len;
} else {
size_t len;
size_t total_len;
if (padding) {
data_len += 1; /* padding */
}
len = data_len + GSS_ARCFOUR_WRAP_TOKEN_SIZE;
_gssapi_encap_length(len, &len, &total_len, GSS_KRB5_MECHANISM);
header->buffer.length = total_len - data_len;
}
if (trailer) {
trailer->buffer.length = 0;
}
if (padding) {
padding->buffer.length = 1;
}
return GSS_S_COMPLETE;
}
OM_uint32
_gssapi_wrap_iov_arcfour(OM_uint32 *minor_status,
gsskrb5_ctx ctx,
krb5_context context,
int conf_req_flag,
int *conf_state,
gss_iov_buffer_desc *iov,
int iov_count,
krb5_keyblock *key)
{
OM_uint32 major_status, junk;
gss_iov_buffer_desc *header, *padding, *trailer;
krb5_error_code kret;
int32_t seq_number;
u_char Klocaldata[16], k6_data[16], *p, *p0;
size_t make_len = 0;
size_t header_len = 0;
size_t data_len = 0;
krb5_keyblock Klocal;
int i;
header = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_HEADER);
padding = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_PADDING);
trailer = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_TRAILER);
major_status = _gk_verify_buffers(minor_status, ctx, header,
padding, trailer, FALSE);
if (major_status != GSS_S_COMPLETE) {
return major_status;
}
for (i = 0; i < iov_count; i++) {
switch (GSS_IOV_BUFFER_TYPE(iov[i].type)) {
case GSS_IOV_BUFFER_TYPE_DATA:
break;
default:
continue;
}
data_len += iov[i].buffer.length;
}
if (padding) {
data_len += 1;
}
if (IS_DCE_STYLE(ctx)) {
size_t unwrapped_len;
unwrapped_len = GSS_ARCFOUR_WRAP_TOKEN_SIZE;
_gssapi_encap_length(unwrapped_len,
&make_len,
&header_len,
GSS_KRB5_MECHANISM);
} else {
size_t unwrapped_len;
unwrapped_len = GSS_ARCFOUR_WRAP_TOKEN_SIZE + data_len;
_gssapi_encap_length(unwrapped_len,
&make_len,
&header_len,
GSS_KRB5_MECHANISM);
header_len -= data_len;
}
if (GSS_IOV_BUFFER_FLAGS(header->type) & GSS_IOV_BUFFER_FLAG_ALLOCATE) {
major_status = _gk_allocate_buffer(minor_status, header,
header_len);
if (major_status != GSS_S_COMPLETE)
goto failure;
} else if (header->buffer.length < header_len) {
*minor_status = KRB5_BAD_MSIZE;
major_status = GSS_S_FAILURE;
goto failure;
} else {
header->buffer.length = header_len;
}
if (padding) {
if (GSS_IOV_BUFFER_FLAGS(padding->type) & GSS_IOV_BUFFER_FLAG_ALLOCATE) {
major_status = _gk_allocate_buffer(minor_status, padding, 1);
if (major_status != GSS_S_COMPLETE)
goto failure;
} else if (padding->buffer.length < 1) {
*minor_status = KRB5_BAD_MSIZE;
major_status = GSS_S_FAILURE;
goto failure;
} else {
padding->buffer.length = 1;
}
memset(padding->buffer.value, 1, 1);
}
if (trailer) {
trailer->buffer.length = 0;
trailer->buffer.value = NULL;
}
p0 = _gssapi_make_mech_header(header->buffer.value,
make_len,
GSS_KRB5_MECHANISM);
p = p0;
*p++ = 0x02; /* TOK_ID */
*p++ = 0x01;
*p++ = 0x11; /* SGN_ALG */
*p++ = 0x00;
if (conf_req_flag) {
*p++ = 0x10; /* SEAL_ALG */
*p++ = 0x00;
} else {
*p++ = 0xff; /* SEAL_ALG */
*p++ = 0xff;
}
*p++ = 0xff; /* Filler */
*p++ = 0xff;
p = NULL;
HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex);
krb5_auth_con_getlocalseqnumber(context,
ctx->auth_context,
&seq_number);
_gsskrb5_encode_be_om_uint32(seq_number, p0 + 8);
krb5_auth_con_setlocalseqnumber(context,
ctx->auth_context,
++seq_number);
HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
memset(p0 + 8 + 4,
(ctx->more_flags & LOCAL) ? 0 : 0xff,
4);
krb5_generate_random_block(p0 + 24, 8); /* fill in Confounder */
/* Sign Data */
kret = arcfour_mic_cksum_iov(context,
key, KRB5_KU_USAGE_SEAL,
p0 + 16, 8, /* SGN_CKSUM */
p0, 8, /* TOK_ID, SGN_ALG, SEAL_ALG, Filler */
p0 + 24, 8, /* Confounder */
iov, iov_count, /* Data + SignOnly */
padding); /* padding */
if (kret) {
*minor_status = kret;
major_status = GSS_S_FAILURE;
goto failure;
}
Klocal.keytype = key->keytype;
Klocal.keyvalue.data = Klocaldata;
Klocal.keyvalue.length = sizeof(Klocaldata);
for (i = 0; i < 16; i++) {
Klocaldata[i] = ((u_char *)key->keyvalue.data)[i] ^ 0xF0;
}
kret = arcfour_mic_key(context, &Klocal,
p0 + 8, 4, /* SND_SEQ */
k6_data, sizeof(k6_data));
memset_s(Klocaldata, sizeof(Klocaldata), 0, sizeof(Klocaldata));
if (kret) {
*minor_status = kret;
major_status = GSS_S_FAILURE;
goto failure;
}
if (conf_req_flag) {
EVP_CIPHER_CTX rc4_key;
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, k6_data, NULL, 1);
/* Confounder */
EVP_Cipher(&rc4_key, p0 + 24, p0 + 24, 8);
/* Seal Data */
for (i=0; i < iov_count; i++) {
switch (GSS_IOV_BUFFER_TYPE(iov[i].type)) {
case GSS_IOV_BUFFER_TYPE_DATA:
break;
default:
continue;
}
EVP_Cipher(&rc4_key, iov[i].buffer.value,
iov[i].buffer.value, iov[i].buffer.length);
}
/* Padding */
if (padding) {
EVP_Cipher(&rc4_key, padding->buffer.value,
padding->buffer.value, padding->buffer.length);
}
EVP_CIPHER_CTX_cleanup(&rc4_key);
}
memset(k6_data, 0, sizeof(k6_data));
kret = arcfour_mic_key(context, key,
p0 + 16, 8, /* SGN_CKSUM */
k6_data, sizeof(k6_data));
if (kret) {
*minor_status = kret;
major_status = GSS_S_FAILURE;
return major_status;
}
{
EVP_CIPHER_CTX rc4_key;
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, k6_data, NULL, 1);
EVP_Cipher(&rc4_key, p0 + 8, p0 + 8, 8); /* SND_SEQ */
EVP_CIPHER_CTX_cleanup(&rc4_key);
memset(k6_data, 0, sizeof(k6_data));
}
if (conf_state)
*conf_state = conf_req_flag;
*minor_status = 0;
return GSS_S_COMPLETE;
failure:
gss_release_iov_buffer(&junk, iov, iov_count);
return major_status;
}
OM_uint32
_gssapi_unwrap_iov_arcfour(OM_uint32 *minor_status,
gsskrb5_ctx ctx,
krb5_context context,
int *pconf_state,
gss_qop_t *pqop_state,
gss_iov_buffer_desc *iov,
int iov_count,
krb5_keyblock *key)
{
OM_uint32 major_status;
gss_iov_buffer_desc *header, *padding, *trailer;
krb5_keyblock Klocal;
uint8_t Klocaldata[16];
uint8_t k6_data[16], snd_seq[8], Confounder[8];
uint8_t cksum_data[8];
uint8_t *_p = NULL;
const uint8_t *p, *p0;
size_t verify_len = 0;
uint32_t seq_number;
size_t hlen = 0;
int conf_state;
int cmp;
size_t i;
krb5_error_code kret;
OM_uint32 ret;
if (pconf_state != NULL) {
*pconf_state = 0;
}
if (pqop_state != NULL) {
*pqop_state = 0;
}
header = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_HEADER);
padding = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_PADDING);
trailer = _gk_find_buffer(iov, iov_count, GSS_IOV_BUFFER_TYPE_TRAILER);
/* Check if the packet is correct */
major_status = _gk_verify_buffers(minor_status,
ctx,
header,
padding,
trailer,
FALSE); /* behaves as stream cipher */
if (major_status != GSS_S_COMPLETE) {
return major_status;
}
if (padding != NULL && padding->buffer.length != 1) {
*minor_status = EINVAL;
return GSS_S_FAILURE;
}
verify_len = header->buffer.length;
if (!IS_DCE_STYLE(ctx)) {
for (i = 0; i < iov_count; i++) {
/* length in header also includes data and padding */
if (GSS_IOV_BUFFER_TYPE(iov[i].type) == GSS_IOV_BUFFER_TYPE_DATA)
verify_len += iov[i].buffer.length;
}
if (padding)
verify_len += padding->buffer.length;
}
_p = header->buffer.value;
ret = _gssapi_verify_mech_header(&_p,
verify_len,
GSS_KRB5_MECHANISM);
if (ret) {
return ret;
}
p0 = _p;
/* length of mech header */
hlen = (p0 - (uint8_t *)header->buffer.value);
hlen += GSS_ARCFOUR_WRAP_TOKEN_SIZE;
if (hlen > header->buffer.length) {
return GSS_S_BAD_MECH;
}
p = p0;
if (memcmp(p, "\x02\x01", 2) != 0)
return GSS_S_BAD_SIG;
p += 2;
if (memcmp(p, "\x11\x00", 2) != 0) /* SGN_ALG = HMAC MD5 ARCFOUR */
return GSS_S_BAD_SIG;
p += 2;
if (memcmp (p, "\x10\x00", 2) == 0)
conf_state = 1;
else if (memcmp (p, "\xff\xff", 2) == 0)
conf_state = 0;
else
return GSS_S_BAD_SIG;
p += 2;
if (memcmp (p, "\xff\xff", 2) != 0)
return GSS_S_BAD_MIC;
p = NULL;
kret = arcfour_mic_key(context,
key,
p0 + 16, /* SGN_CKSUM */
8, /* SGN_CKSUM_LEN */
k6_data,
sizeof(k6_data));
if (kret) {
*minor_status = kret;
return GSS_S_FAILURE;
}
{
EVP_CIPHER_CTX rc4_key;
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, k6_data, NULL, 1);
EVP_Cipher(&rc4_key, snd_seq, p0 + 8, 8); /* SND_SEQ */
EVP_CIPHER_CTX_cleanup(&rc4_key);
memset(k6_data, 0, sizeof(k6_data));
}
_gsskrb5_decode_be_om_uint32(snd_seq, &seq_number);
if (ctx->more_flags & LOCAL) {
cmp = (memcmp(&snd_seq[4], "\xff\xff\xff\xff", 4) != 0);
} else {
cmp = (memcmp(&snd_seq[4], "\x00\x00\x00\x00", 4) != 0);
}
if (cmp != 0) {
*minor_status = 0;
return GSS_S_BAD_MIC;
}
/* keyblock */
Klocal.keytype = key->keytype;
Klocal.keyvalue.data = Klocaldata;
Klocal.keyvalue.length = sizeof(Klocaldata);
for (i = 0; i < 16; i++) {
Klocaldata[i] = ((u_char *)key->keyvalue.data)[i] ^ 0xF0;
}
kret = arcfour_mic_key(context,
&Klocal,
snd_seq,
4,
k6_data, sizeof(k6_data));
memset_s(Klocaldata, sizeof(Klocaldata), 0, sizeof(Klocaldata));
if (kret) {
*minor_status = kret;
return GSS_S_FAILURE;
}
if (conf_state == 1) {
EVP_CIPHER_CTX rc4_key;
EVP_CIPHER_CTX_init(&rc4_key);
EVP_CipherInit_ex(&rc4_key, EVP_rc4(), NULL, k6_data, NULL, 1);
/* Confounder */
EVP_Cipher(&rc4_key, Confounder, p0 + 24, 8);
/* Data */
for (i = 0; i < iov_count; i++) {
switch (GSS_IOV_BUFFER_TYPE(iov[i].type)) {
case GSS_IOV_BUFFER_TYPE_DATA:
break;
default:
continue;
}
EVP_Cipher(&rc4_key, iov[i].buffer.value,
iov[i].buffer.value, iov[i].buffer.length);
}
/* Padding */
if (padding) {
EVP_Cipher(&rc4_key, padding->buffer.value,
padding->buffer.value, padding->buffer.length);
}
EVP_CIPHER_CTX_cleanup(&rc4_key);
} else {
/* Confounder */
memcpy(Confounder, p0 + 24, 8);
}
memset(k6_data, 0, sizeof(k6_data));
/* Prepare the buffer for signing */
kret = arcfour_mic_cksum_iov(context,
key, KRB5_KU_USAGE_SEAL,
cksum_data, sizeof(cksum_data),
p0, 8,
Confounder, sizeof(Confounder),
iov, iov_count,
padding);
if (kret) {
*minor_status = kret;
return GSS_S_FAILURE;
}
cmp = (memcmp(cksum_data, p0 + 16, 8) != 0); /* SGN_CKSUM */
if (cmp) {
*minor_status = 0;
return GSS_S_BAD_MIC;
}
if (padding) {
size_t plen;
ret = _gssapi_verify_pad(&padding->buffer, 1, &plen);
if (ret) {
*minor_status = 0;
return ret;
}
}
HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex);
ret = _gssapi_msg_order_check(ctx->order, seq_number);
HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
if (ret != 0) {
return ret;
}
if (pconf_state) {
*pconf_state = conf_state;
}
*minor_status = 0;
return GSS_S_COMPLETE;
}
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