mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-06 02:24:14 +08:00
1474774a7f
This patch is to remove the typedef sctp_hmac_algo_param_t, and replace with struct sctp_hmac_algo_param in the places where it's using this typedef. It is also to use sizeof(variable) instead of sizeof(type). Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
959 lines
24 KiB
C
959 lines
24 KiB
C
/* SCTP kernel implementation
|
|
* (C) Copyright 2007 Hewlett-Packard Development Company, L.P.
|
|
*
|
|
* This file is part of the SCTP kernel implementation
|
|
*
|
|
* This SCTP implementation is free software;
|
|
* you can redistribute it and/or modify it under the terms of
|
|
* the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2, or (at your option)
|
|
* any later version.
|
|
*
|
|
* This SCTP implementation is distributed in the hope that it
|
|
* will be useful, but WITHOUT ANY WARRANTY; without even the implied
|
|
* ************************
|
|
* warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
|
|
* See the GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with GNU CC; see the file COPYING. If not, see
|
|
* <http://www.gnu.org/licenses/>.
|
|
*
|
|
* Please send any bug reports or fixes you make to the
|
|
* email address(es):
|
|
* lksctp developers <linux-sctp@vger.kernel.org>
|
|
*
|
|
* Written or modified by:
|
|
* Vlad Yasevich <vladislav.yasevich@hp.com>
|
|
*/
|
|
|
|
#include <crypto/hash.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/types.h>
|
|
#include <linux/scatterlist.h>
|
|
#include <net/sctp/sctp.h>
|
|
#include <net/sctp/auth.h>
|
|
|
|
static struct sctp_hmac sctp_hmac_list[SCTP_AUTH_NUM_HMACS] = {
|
|
{
|
|
/* id 0 is reserved. as all 0 */
|
|
.hmac_id = SCTP_AUTH_HMAC_ID_RESERVED_0,
|
|
},
|
|
{
|
|
.hmac_id = SCTP_AUTH_HMAC_ID_SHA1,
|
|
.hmac_name = "hmac(sha1)",
|
|
.hmac_len = SCTP_SHA1_SIG_SIZE,
|
|
},
|
|
{
|
|
/* id 2 is reserved as well */
|
|
.hmac_id = SCTP_AUTH_HMAC_ID_RESERVED_2,
|
|
},
|
|
#if IS_ENABLED(CONFIG_CRYPTO_SHA256)
|
|
{
|
|
.hmac_id = SCTP_AUTH_HMAC_ID_SHA256,
|
|
.hmac_name = "hmac(sha256)",
|
|
.hmac_len = SCTP_SHA256_SIG_SIZE,
|
|
}
|
|
#endif
|
|
};
|
|
|
|
|
|
void sctp_auth_key_put(struct sctp_auth_bytes *key)
|
|
{
|
|
if (!key)
|
|
return;
|
|
|
|
if (refcount_dec_and_test(&key->refcnt)) {
|
|
kzfree(key);
|
|
SCTP_DBG_OBJCNT_DEC(keys);
|
|
}
|
|
}
|
|
|
|
/* Create a new key structure of a given length */
|
|
static struct sctp_auth_bytes *sctp_auth_create_key(__u32 key_len, gfp_t gfp)
|
|
{
|
|
struct sctp_auth_bytes *key;
|
|
|
|
/* Verify that we are not going to overflow INT_MAX */
|
|
if (key_len > (INT_MAX - sizeof(struct sctp_auth_bytes)))
|
|
return NULL;
|
|
|
|
/* Allocate the shared key */
|
|
key = kmalloc(sizeof(struct sctp_auth_bytes) + key_len, gfp);
|
|
if (!key)
|
|
return NULL;
|
|
|
|
key->len = key_len;
|
|
refcount_set(&key->refcnt, 1);
|
|
SCTP_DBG_OBJCNT_INC(keys);
|
|
|
|
return key;
|
|
}
|
|
|
|
/* Create a new shared key container with a give key id */
|
|
struct sctp_shared_key *sctp_auth_shkey_create(__u16 key_id, gfp_t gfp)
|
|
{
|
|
struct sctp_shared_key *new;
|
|
|
|
/* Allocate the shared key container */
|
|
new = kzalloc(sizeof(struct sctp_shared_key), gfp);
|
|
if (!new)
|
|
return NULL;
|
|
|
|
INIT_LIST_HEAD(&new->key_list);
|
|
new->key_id = key_id;
|
|
|
|
return new;
|
|
}
|
|
|
|
/* Free the shared key structure */
|
|
static void sctp_auth_shkey_free(struct sctp_shared_key *sh_key)
|
|
{
|
|
BUG_ON(!list_empty(&sh_key->key_list));
|
|
sctp_auth_key_put(sh_key->key);
|
|
sh_key->key = NULL;
|
|
kfree(sh_key);
|
|
}
|
|
|
|
/* Destroy the entire key list. This is done during the
|
|
* associon and endpoint free process.
|
|
*/
|
|
void sctp_auth_destroy_keys(struct list_head *keys)
|
|
{
|
|
struct sctp_shared_key *ep_key;
|
|
struct sctp_shared_key *tmp;
|
|
|
|
if (list_empty(keys))
|
|
return;
|
|
|
|
key_for_each_safe(ep_key, tmp, keys) {
|
|
list_del_init(&ep_key->key_list);
|
|
sctp_auth_shkey_free(ep_key);
|
|
}
|
|
}
|
|
|
|
/* Compare two byte vectors as numbers. Return values
|
|
* are:
|
|
* 0 - vectors are equal
|
|
* < 0 - vector 1 is smaller than vector2
|
|
* > 0 - vector 1 is greater than vector2
|
|
*
|
|
* Algorithm is:
|
|
* This is performed by selecting the numerically smaller key vector...
|
|
* If the key vectors are equal as numbers but differ in length ...
|
|
* the shorter vector is considered smaller
|
|
*
|
|
* Examples (with small values):
|
|
* 000123456789 > 123456789 (first number is longer)
|
|
* 000123456789 < 234567891 (second number is larger numerically)
|
|
* 123456789 > 2345678 (first number is both larger & longer)
|
|
*/
|
|
static int sctp_auth_compare_vectors(struct sctp_auth_bytes *vector1,
|
|
struct sctp_auth_bytes *vector2)
|
|
{
|
|
int diff;
|
|
int i;
|
|
const __u8 *longer;
|
|
|
|
diff = vector1->len - vector2->len;
|
|
if (diff) {
|
|
longer = (diff > 0) ? vector1->data : vector2->data;
|
|
|
|
/* Check to see if the longer number is
|
|
* lead-zero padded. If it is not, it
|
|
* is automatically larger numerically.
|
|
*/
|
|
for (i = 0; i < abs(diff); i++) {
|
|
if (longer[i] != 0)
|
|
return diff;
|
|
}
|
|
}
|
|
|
|
/* lengths are the same, compare numbers */
|
|
return memcmp(vector1->data, vector2->data, vector1->len);
|
|
}
|
|
|
|
/*
|
|
* Create a key vector as described in SCTP-AUTH, Section 6.1
|
|
* The RANDOM parameter, the CHUNKS parameter and the HMAC-ALGO
|
|
* parameter sent by each endpoint are concatenated as byte vectors.
|
|
* These parameters include the parameter type, parameter length, and
|
|
* the parameter value, but padding is omitted; all padding MUST be
|
|
* removed from this concatenation before proceeding with further
|
|
* computation of keys. Parameters which were not sent are simply
|
|
* omitted from the concatenation process. The resulting two vectors
|
|
* are called the two key vectors.
|
|
*/
|
|
static struct sctp_auth_bytes *sctp_auth_make_key_vector(
|
|
struct sctp_random_param *random,
|
|
struct sctp_chunks_param *chunks,
|
|
struct sctp_hmac_algo_param *hmacs,
|
|
gfp_t gfp)
|
|
{
|
|
struct sctp_auth_bytes *new;
|
|
__u32 len;
|
|
__u32 offset = 0;
|
|
__u16 random_len, hmacs_len, chunks_len = 0;
|
|
|
|
random_len = ntohs(random->param_hdr.length);
|
|
hmacs_len = ntohs(hmacs->param_hdr.length);
|
|
if (chunks)
|
|
chunks_len = ntohs(chunks->param_hdr.length);
|
|
|
|
len = random_len + hmacs_len + chunks_len;
|
|
|
|
new = sctp_auth_create_key(len, gfp);
|
|
if (!new)
|
|
return NULL;
|
|
|
|
memcpy(new->data, random, random_len);
|
|
offset += random_len;
|
|
|
|
if (chunks) {
|
|
memcpy(new->data + offset, chunks, chunks_len);
|
|
offset += chunks_len;
|
|
}
|
|
|
|
memcpy(new->data + offset, hmacs, hmacs_len);
|
|
|
|
return new;
|
|
}
|
|
|
|
|
|
/* Make a key vector based on our local parameters */
|
|
static struct sctp_auth_bytes *sctp_auth_make_local_vector(
|
|
const struct sctp_association *asoc,
|
|
gfp_t gfp)
|
|
{
|
|
return sctp_auth_make_key_vector(
|
|
(struct sctp_random_param *)asoc->c.auth_random,
|
|
(struct sctp_chunks_param *)asoc->c.auth_chunks,
|
|
(struct sctp_hmac_algo_param *)asoc->c.auth_hmacs, gfp);
|
|
}
|
|
|
|
/* Make a key vector based on peer's parameters */
|
|
static struct sctp_auth_bytes *sctp_auth_make_peer_vector(
|
|
const struct sctp_association *asoc,
|
|
gfp_t gfp)
|
|
{
|
|
return sctp_auth_make_key_vector(asoc->peer.peer_random,
|
|
asoc->peer.peer_chunks,
|
|
asoc->peer.peer_hmacs,
|
|
gfp);
|
|
}
|
|
|
|
|
|
/* Set the value of the association shared key base on the parameters
|
|
* given. The algorithm is:
|
|
* From the endpoint pair shared keys and the key vectors the
|
|
* association shared keys are computed. This is performed by selecting
|
|
* the numerically smaller key vector and concatenating it to the
|
|
* endpoint pair shared key, and then concatenating the numerically
|
|
* larger key vector to that. The result of the concatenation is the
|
|
* association shared key.
|
|
*/
|
|
static struct sctp_auth_bytes *sctp_auth_asoc_set_secret(
|
|
struct sctp_shared_key *ep_key,
|
|
struct sctp_auth_bytes *first_vector,
|
|
struct sctp_auth_bytes *last_vector,
|
|
gfp_t gfp)
|
|
{
|
|
struct sctp_auth_bytes *secret;
|
|
__u32 offset = 0;
|
|
__u32 auth_len;
|
|
|
|
auth_len = first_vector->len + last_vector->len;
|
|
if (ep_key->key)
|
|
auth_len += ep_key->key->len;
|
|
|
|
secret = sctp_auth_create_key(auth_len, gfp);
|
|
if (!secret)
|
|
return NULL;
|
|
|
|
if (ep_key->key) {
|
|
memcpy(secret->data, ep_key->key->data, ep_key->key->len);
|
|
offset += ep_key->key->len;
|
|
}
|
|
|
|
memcpy(secret->data + offset, first_vector->data, first_vector->len);
|
|
offset += first_vector->len;
|
|
|
|
memcpy(secret->data + offset, last_vector->data, last_vector->len);
|
|
|
|
return secret;
|
|
}
|
|
|
|
/* Create an association shared key. Follow the algorithm
|
|
* described in SCTP-AUTH, Section 6.1
|
|
*/
|
|
static struct sctp_auth_bytes *sctp_auth_asoc_create_secret(
|
|
const struct sctp_association *asoc,
|
|
struct sctp_shared_key *ep_key,
|
|
gfp_t gfp)
|
|
{
|
|
struct sctp_auth_bytes *local_key_vector;
|
|
struct sctp_auth_bytes *peer_key_vector;
|
|
struct sctp_auth_bytes *first_vector,
|
|
*last_vector;
|
|
struct sctp_auth_bytes *secret = NULL;
|
|
int cmp;
|
|
|
|
|
|
/* Now we need to build the key vectors
|
|
* SCTP-AUTH , Section 6.1
|
|
* The RANDOM parameter, the CHUNKS parameter and the HMAC-ALGO
|
|
* parameter sent by each endpoint are concatenated as byte vectors.
|
|
* These parameters include the parameter type, parameter length, and
|
|
* the parameter value, but padding is omitted; all padding MUST be
|
|
* removed from this concatenation before proceeding with further
|
|
* computation of keys. Parameters which were not sent are simply
|
|
* omitted from the concatenation process. The resulting two vectors
|
|
* are called the two key vectors.
|
|
*/
|
|
|
|
local_key_vector = sctp_auth_make_local_vector(asoc, gfp);
|
|
peer_key_vector = sctp_auth_make_peer_vector(asoc, gfp);
|
|
|
|
if (!peer_key_vector || !local_key_vector)
|
|
goto out;
|
|
|
|
/* Figure out the order in which the key_vectors will be
|
|
* added to the endpoint shared key.
|
|
* SCTP-AUTH, Section 6.1:
|
|
* This is performed by selecting the numerically smaller key
|
|
* vector and concatenating it to the endpoint pair shared
|
|
* key, and then concatenating the numerically larger key
|
|
* vector to that. If the key vectors are equal as numbers
|
|
* but differ in length, then the concatenation order is the
|
|
* endpoint shared key, followed by the shorter key vector,
|
|
* followed by the longer key vector. Otherwise, the key
|
|
* vectors are identical, and may be concatenated to the
|
|
* endpoint pair key in any order.
|
|
*/
|
|
cmp = sctp_auth_compare_vectors(local_key_vector,
|
|
peer_key_vector);
|
|
if (cmp < 0) {
|
|
first_vector = local_key_vector;
|
|
last_vector = peer_key_vector;
|
|
} else {
|
|
first_vector = peer_key_vector;
|
|
last_vector = local_key_vector;
|
|
}
|
|
|
|
secret = sctp_auth_asoc_set_secret(ep_key, first_vector, last_vector,
|
|
gfp);
|
|
out:
|
|
sctp_auth_key_put(local_key_vector);
|
|
sctp_auth_key_put(peer_key_vector);
|
|
|
|
return secret;
|
|
}
|
|
|
|
/*
|
|
* Populate the association overlay list with the list
|
|
* from the endpoint.
|
|
*/
|
|
int sctp_auth_asoc_copy_shkeys(const struct sctp_endpoint *ep,
|
|
struct sctp_association *asoc,
|
|
gfp_t gfp)
|
|
{
|
|
struct sctp_shared_key *sh_key;
|
|
struct sctp_shared_key *new;
|
|
|
|
BUG_ON(!list_empty(&asoc->endpoint_shared_keys));
|
|
|
|
key_for_each(sh_key, &ep->endpoint_shared_keys) {
|
|
new = sctp_auth_shkey_create(sh_key->key_id, gfp);
|
|
if (!new)
|
|
goto nomem;
|
|
|
|
new->key = sh_key->key;
|
|
sctp_auth_key_hold(new->key);
|
|
list_add(&new->key_list, &asoc->endpoint_shared_keys);
|
|
}
|
|
|
|
return 0;
|
|
|
|
nomem:
|
|
sctp_auth_destroy_keys(&asoc->endpoint_shared_keys);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
|
|
/* Public interface to create the association shared key.
|
|
* See code above for the algorithm.
|
|
*/
|
|
int sctp_auth_asoc_init_active_key(struct sctp_association *asoc, gfp_t gfp)
|
|
{
|
|
struct sctp_auth_bytes *secret;
|
|
struct sctp_shared_key *ep_key;
|
|
struct sctp_chunk *chunk;
|
|
|
|
/* If we don't support AUTH, or peer is not capable
|
|
* we don't need to do anything.
|
|
*/
|
|
if (!asoc->ep->auth_enable || !asoc->peer.auth_capable)
|
|
return 0;
|
|
|
|
/* If the key_id is non-zero and we couldn't find an
|
|
* endpoint pair shared key, we can't compute the
|
|
* secret.
|
|
* For key_id 0, endpoint pair shared key is a NULL key.
|
|
*/
|
|
ep_key = sctp_auth_get_shkey(asoc, asoc->active_key_id);
|
|
BUG_ON(!ep_key);
|
|
|
|
secret = sctp_auth_asoc_create_secret(asoc, ep_key, gfp);
|
|
if (!secret)
|
|
return -ENOMEM;
|
|
|
|
sctp_auth_key_put(asoc->asoc_shared_key);
|
|
asoc->asoc_shared_key = secret;
|
|
|
|
/* Update send queue in case any chunk already in there now
|
|
* needs authenticating
|
|
*/
|
|
list_for_each_entry(chunk, &asoc->outqueue.out_chunk_list, list) {
|
|
if (sctp_auth_send_cid(chunk->chunk_hdr->type, asoc))
|
|
chunk->auth = 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Find the endpoint pair shared key based on the key_id */
|
|
struct sctp_shared_key *sctp_auth_get_shkey(
|
|
const struct sctp_association *asoc,
|
|
__u16 key_id)
|
|
{
|
|
struct sctp_shared_key *key;
|
|
|
|
/* First search associations set of endpoint pair shared keys */
|
|
key_for_each(key, &asoc->endpoint_shared_keys) {
|
|
if (key->key_id == key_id)
|
|
return key;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Initialize all the possible digest transforms that we can use. Right now
|
|
* now, the supported digests are SHA1 and SHA256. We do this here once
|
|
* because of the restrictiong that transforms may only be allocated in
|
|
* user context. This forces us to pre-allocated all possible transforms
|
|
* at the endpoint init time.
|
|
*/
|
|
int sctp_auth_init_hmacs(struct sctp_endpoint *ep, gfp_t gfp)
|
|
{
|
|
struct crypto_shash *tfm = NULL;
|
|
__u16 id;
|
|
|
|
/* If AUTH extension is disabled, we are done */
|
|
if (!ep->auth_enable) {
|
|
ep->auth_hmacs = NULL;
|
|
return 0;
|
|
}
|
|
|
|
/* If the transforms are already allocated, we are done */
|
|
if (ep->auth_hmacs)
|
|
return 0;
|
|
|
|
/* Allocated the array of pointers to transorms */
|
|
ep->auth_hmacs = kzalloc(sizeof(struct crypto_shash *) *
|
|
SCTP_AUTH_NUM_HMACS, gfp);
|
|
if (!ep->auth_hmacs)
|
|
return -ENOMEM;
|
|
|
|
for (id = 0; id < SCTP_AUTH_NUM_HMACS; id++) {
|
|
|
|
/* See is we support the id. Supported IDs have name and
|
|
* length fields set, so that we can allocated and use
|
|
* them. We can safely just check for name, for without the
|
|
* name, we can't allocate the TFM.
|
|
*/
|
|
if (!sctp_hmac_list[id].hmac_name)
|
|
continue;
|
|
|
|
/* If this TFM has been allocated, we are all set */
|
|
if (ep->auth_hmacs[id])
|
|
continue;
|
|
|
|
/* Allocate the ID */
|
|
tfm = crypto_alloc_shash(sctp_hmac_list[id].hmac_name, 0, 0);
|
|
if (IS_ERR(tfm))
|
|
goto out_err;
|
|
|
|
ep->auth_hmacs[id] = tfm;
|
|
}
|
|
|
|
return 0;
|
|
|
|
out_err:
|
|
/* Clean up any successful allocations */
|
|
sctp_auth_destroy_hmacs(ep->auth_hmacs);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Destroy the hmac tfm array */
|
|
void sctp_auth_destroy_hmacs(struct crypto_shash *auth_hmacs[])
|
|
{
|
|
int i;
|
|
|
|
if (!auth_hmacs)
|
|
return;
|
|
|
|
for (i = 0; i < SCTP_AUTH_NUM_HMACS; i++) {
|
|
crypto_free_shash(auth_hmacs[i]);
|
|
}
|
|
kfree(auth_hmacs);
|
|
}
|
|
|
|
|
|
struct sctp_hmac *sctp_auth_get_hmac(__u16 hmac_id)
|
|
{
|
|
return &sctp_hmac_list[hmac_id];
|
|
}
|
|
|
|
/* Get an hmac description information that we can use to build
|
|
* the AUTH chunk
|
|
*/
|
|
struct sctp_hmac *sctp_auth_asoc_get_hmac(const struct sctp_association *asoc)
|
|
{
|
|
struct sctp_hmac_algo_param *hmacs;
|
|
__u16 n_elt;
|
|
__u16 id = 0;
|
|
int i;
|
|
|
|
/* If we have a default entry, use it */
|
|
if (asoc->default_hmac_id)
|
|
return &sctp_hmac_list[asoc->default_hmac_id];
|
|
|
|
/* Since we do not have a default entry, find the first entry
|
|
* we support and return that. Do not cache that id.
|
|
*/
|
|
hmacs = asoc->peer.peer_hmacs;
|
|
if (!hmacs)
|
|
return NULL;
|
|
|
|
n_elt = (ntohs(hmacs->param_hdr.length) -
|
|
sizeof(struct sctp_paramhdr)) >> 1;
|
|
for (i = 0; i < n_elt; i++) {
|
|
id = ntohs(hmacs->hmac_ids[i]);
|
|
|
|
/* Check the id is in the supported range. And
|
|
* see if we support the id. Supported IDs have name and
|
|
* length fields set, so that we can allocate and use
|
|
* them. We can safely just check for name, for without the
|
|
* name, we can't allocate the TFM.
|
|
*/
|
|
if (id > SCTP_AUTH_HMAC_ID_MAX ||
|
|
!sctp_hmac_list[id].hmac_name) {
|
|
id = 0;
|
|
continue;
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
if (id == 0)
|
|
return NULL;
|
|
|
|
return &sctp_hmac_list[id];
|
|
}
|
|
|
|
static int __sctp_auth_find_hmacid(__be16 *hmacs, int n_elts, __be16 hmac_id)
|
|
{
|
|
int found = 0;
|
|
int i;
|
|
|
|
for (i = 0; i < n_elts; i++) {
|
|
if (hmac_id == hmacs[i]) {
|
|
found = 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return found;
|
|
}
|
|
|
|
/* See if the HMAC_ID is one that we claim as supported */
|
|
int sctp_auth_asoc_verify_hmac_id(const struct sctp_association *asoc,
|
|
__be16 hmac_id)
|
|
{
|
|
struct sctp_hmac_algo_param *hmacs;
|
|
__u16 n_elt;
|
|
|
|
if (!asoc)
|
|
return 0;
|
|
|
|
hmacs = (struct sctp_hmac_algo_param *)asoc->c.auth_hmacs;
|
|
n_elt = (ntohs(hmacs->param_hdr.length) -
|
|
sizeof(struct sctp_paramhdr)) >> 1;
|
|
|
|
return __sctp_auth_find_hmacid(hmacs->hmac_ids, n_elt, hmac_id);
|
|
}
|
|
|
|
|
|
/* Cache the default HMAC id. This to follow this text from SCTP-AUTH:
|
|
* Section 6.1:
|
|
* The receiver of a HMAC-ALGO parameter SHOULD use the first listed
|
|
* algorithm it supports.
|
|
*/
|
|
void sctp_auth_asoc_set_default_hmac(struct sctp_association *asoc,
|
|
struct sctp_hmac_algo_param *hmacs)
|
|
{
|
|
struct sctp_endpoint *ep;
|
|
__u16 id;
|
|
int i;
|
|
int n_params;
|
|
|
|
/* if the default id is already set, use it */
|
|
if (asoc->default_hmac_id)
|
|
return;
|
|
|
|
n_params = (ntohs(hmacs->param_hdr.length) -
|
|
sizeof(struct sctp_paramhdr)) >> 1;
|
|
ep = asoc->ep;
|
|
for (i = 0; i < n_params; i++) {
|
|
id = ntohs(hmacs->hmac_ids[i]);
|
|
|
|
/* Check the id is in the supported range */
|
|
if (id > SCTP_AUTH_HMAC_ID_MAX)
|
|
continue;
|
|
|
|
/* If this TFM has been allocated, use this id */
|
|
if (ep->auth_hmacs[id]) {
|
|
asoc->default_hmac_id = id;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/* Check to see if the given chunk is supposed to be authenticated */
|
|
static int __sctp_auth_cid(enum sctp_cid chunk, struct sctp_chunks_param *param)
|
|
{
|
|
unsigned short len;
|
|
int found = 0;
|
|
int i;
|
|
|
|
if (!param || param->param_hdr.length == 0)
|
|
return 0;
|
|
|
|
len = ntohs(param->param_hdr.length) - sizeof(struct sctp_paramhdr);
|
|
|
|
/* SCTP-AUTH, Section 3.2
|
|
* The chunk types for INIT, INIT-ACK, SHUTDOWN-COMPLETE and AUTH
|
|
* chunks MUST NOT be listed in the CHUNKS parameter. However, if
|
|
* a CHUNKS parameter is received then the types for INIT, INIT-ACK,
|
|
* SHUTDOWN-COMPLETE and AUTH chunks MUST be ignored.
|
|
*/
|
|
for (i = 0; !found && i < len; i++) {
|
|
switch (param->chunks[i]) {
|
|
case SCTP_CID_INIT:
|
|
case SCTP_CID_INIT_ACK:
|
|
case SCTP_CID_SHUTDOWN_COMPLETE:
|
|
case SCTP_CID_AUTH:
|
|
break;
|
|
|
|
default:
|
|
if (param->chunks[i] == chunk)
|
|
found = 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
return found;
|
|
}
|
|
|
|
/* Check if peer requested that this chunk is authenticated */
|
|
int sctp_auth_send_cid(enum sctp_cid chunk, const struct sctp_association *asoc)
|
|
{
|
|
if (!asoc)
|
|
return 0;
|
|
|
|
if (!asoc->ep->auth_enable || !asoc->peer.auth_capable)
|
|
return 0;
|
|
|
|
return __sctp_auth_cid(chunk, asoc->peer.peer_chunks);
|
|
}
|
|
|
|
/* Check if we requested that peer authenticate this chunk. */
|
|
int sctp_auth_recv_cid(enum sctp_cid chunk, const struct sctp_association *asoc)
|
|
{
|
|
if (!asoc)
|
|
return 0;
|
|
|
|
if (!asoc->ep->auth_enable)
|
|
return 0;
|
|
|
|
return __sctp_auth_cid(chunk,
|
|
(struct sctp_chunks_param *)asoc->c.auth_chunks);
|
|
}
|
|
|
|
/* SCTP-AUTH: Section 6.2:
|
|
* The sender MUST calculate the MAC as described in RFC2104 [2] using
|
|
* the hash function H as described by the MAC Identifier and the shared
|
|
* association key K based on the endpoint pair shared key described by
|
|
* the shared key identifier. The 'data' used for the computation of
|
|
* the AUTH-chunk is given by the AUTH chunk with its HMAC field set to
|
|
* zero (as shown in Figure 6) followed by all chunks that are placed
|
|
* after the AUTH chunk in the SCTP packet.
|
|
*/
|
|
void sctp_auth_calculate_hmac(const struct sctp_association *asoc,
|
|
struct sk_buff *skb,
|
|
struct sctp_auth_chunk *auth,
|
|
gfp_t gfp)
|
|
{
|
|
struct crypto_shash *tfm;
|
|
struct sctp_auth_bytes *asoc_key;
|
|
__u16 key_id, hmac_id;
|
|
__u8 *digest;
|
|
unsigned char *end;
|
|
int free_key = 0;
|
|
|
|
/* Extract the info we need:
|
|
* - hmac id
|
|
* - key id
|
|
*/
|
|
key_id = ntohs(auth->auth_hdr.shkey_id);
|
|
hmac_id = ntohs(auth->auth_hdr.hmac_id);
|
|
|
|
if (key_id == asoc->active_key_id)
|
|
asoc_key = asoc->asoc_shared_key;
|
|
else {
|
|
struct sctp_shared_key *ep_key;
|
|
|
|
ep_key = sctp_auth_get_shkey(asoc, key_id);
|
|
if (!ep_key)
|
|
return;
|
|
|
|
asoc_key = sctp_auth_asoc_create_secret(asoc, ep_key, gfp);
|
|
if (!asoc_key)
|
|
return;
|
|
|
|
free_key = 1;
|
|
}
|
|
|
|
/* set up scatter list */
|
|
end = skb_tail_pointer(skb);
|
|
|
|
tfm = asoc->ep->auth_hmacs[hmac_id];
|
|
|
|
digest = auth->auth_hdr.hmac;
|
|
if (crypto_shash_setkey(tfm, &asoc_key->data[0], asoc_key->len))
|
|
goto free;
|
|
|
|
{
|
|
SHASH_DESC_ON_STACK(desc, tfm);
|
|
|
|
desc->tfm = tfm;
|
|
desc->flags = 0;
|
|
crypto_shash_digest(desc, (u8 *)auth,
|
|
end - (unsigned char *)auth, digest);
|
|
shash_desc_zero(desc);
|
|
}
|
|
|
|
free:
|
|
if (free_key)
|
|
sctp_auth_key_put(asoc_key);
|
|
}
|
|
|
|
/* API Helpers */
|
|
|
|
/* Add a chunk to the endpoint authenticated chunk list */
|
|
int sctp_auth_ep_add_chunkid(struct sctp_endpoint *ep, __u8 chunk_id)
|
|
{
|
|
struct sctp_chunks_param *p = ep->auth_chunk_list;
|
|
__u16 nchunks;
|
|
__u16 param_len;
|
|
|
|
/* If this chunk is already specified, we are done */
|
|
if (__sctp_auth_cid(chunk_id, p))
|
|
return 0;
|
|
|
|
/* Check if we can add this chunk to the array */
|
|
param_len = ntohs(p->param_hdr.length);
|
|
nchunks = param_len - sizeof(struct sctp_paramhdr);
|
|
if (nchunks == SCTP_NUM_CHUNK_TYPES)
|
|
return -EINVAL;
|
|
|
|
p->chunks[nchunks] = chunk_id;
|
|
p->param_hdr.length = htons(param_len + 1);
|
|
return 0;
|
|
}
|
|
|
|
/* Add hmac identifires to the endpoint list of supported hmac ids */
|
|
int sctp_auth_ep_set_hmacs(struct sctp_endpoint *ep,
|
|
struct sctp_hmacalgo *hmacs)
|
|
{
|
|
int has_sha1 = 0;
|
|
__u16 id;
|
|
int i;
|
|
|
|
/* Scan the list looking for unsupported id. Also make sure that
|
|
* SHA1 is specified.
|
|
*/
|
|
for (i = 0; i < hmacs->shmac_num_idents; i++) {
|
|
id = hmacs->shmac_idents[i];
|
|
|
|
if (id > SCTP_AUTH_HMAC_ID_MAX)
|
|
return -EOPNOTSUPP;
|
|
|
|
if (SCTP_AUTH_HMAC_ID_SHA1 == id)
|
|
has_sha1 = 1;
|
|
|
|
if (!sctp_hmac_list[id].hmac_name)
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
if (!has_sha1)
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < hmacs->shmac_num_idents; i++)
|
|
ep->auth_hmacs_list->hmac_ids[i] =
|
|
htons(hmacs->shmac_idents[i]);
|
|
ep->auth_hmacs_list->param_hdr.length =
|
|
htons(sizeof(struct sctp_paramhdr) +
|
|
hmacs->shmac_num_idents * sizeof(__u16));
|
|
return 0;
|
|
}
|
|
|
|
/* Set a new shared key on either endpoint or association. If the
|
|
* the key with a same ID already exists, replace the key (remove the
|
|
* old key and add a new one).
|
|
*/
|
|
int sctp_auth_set_key(struct sctp_endpoint *ep,
|
|
struct sctp_association *asoc,
|
|
struct sctp_authkey *auth_key)
|
|
{
|
|
struct sctp_shared_key *cur_key = NULL;
|
|
struct sctp_auth_bytes *key;
|
|
struct list_head *sh_keys;
|
|
int replace = 0;
|
|
|
|
/* Try to find the given key id to see if
|
|
* we are doing a replace, or adding a new key
|
|
*/
|
|
if (asoc)
|
|
sh_keys = &asoc->endpoint_shared_keys;
|
|
else
|
|
sh_keys = &ep->endpoint_shared_keys;
|
|
|
|
key_for_each(cur_key, sh_keys) {
|
|
if (cur_key->key_id == auth_key->sca_keynumber) {
|
|
replace = 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* If we are not replacing a key id, we need to allocate
|
|
* a shared key.
|
|
*/
|
|
if (!replace) {
|
|
cur_key = sctp_auth_shkey_create(auth_key->sca_keynumber,
|
|
GFP_KERNEL);
|
|
if (!cur_key)
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* Create a new key data based on the info passed in */
|
|
key = sctp_auth_create_key(auth_key->sca_keylength, GFP_KERNEL);
|
|
if (!key)
|
|
goto nomem;
|
|
|
|
memcpy(key->data, &auth_key->sca_key[0], auth_key->sca_keylength);
|
|
|
|
/* If we are replacing, remove the old keys data from the
|
|
* key id. If we are adding new key id, add it to the
|
|
* list.
|
|
*/
|
|
if (replace)
|
|
sctp_auth_key_put(cur_key->key);
|
|
else
|
|
list_add(&cur_key->key_list, sh_keys);
|
|
|
|
cur_key->key = key;
|
|
return 0;
|
|
nomem:
|
|
if (!replace)
|
|
sctp_auth_shkey_free(cur_key);
|
|
|
|
return -ENOMEM;
|
|
}
|
|
|
|
int sctp_auth_set_active_key(struct sctp_endpoint *ep,
|
|
struct sctp_association *asoc,
|
|
__u16 key_id)
|
|
{
|
|
struct sctp_shared_key *key;
|
|
struct list_head *sh_keys;
|
|
int found = 0;
|
|
|
|
/* The key identifier MUST correst to an existing key */
|
|
if (asoc)
|
|
sh_keys = &asoc->endpoint_shared_keys;
|
|
else
|
|
sh_keys = &ep->endpoint_shared_keys;
|
|
|
|
key_for_each(key, sh_keys) {
|
|
if (key->key_id == key_id) {
|
|
found = 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (!found)
|
|
return -EINVAL;
|
|
|
|
if (asoc) {
|
|
asoc->active_key_id = key_id;
|
|
sctp_auth_asoc_init_active_key(asoc, GFP_KERNEL);
|
|
} else
|
|
ep->active_key_id = key_id;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int sctp_auth_del_key_id(struct sctp_endpoint *ep,
|
|
struct sctp_association *asoc,
|
|
__u16 key_id)
|
|
{
|
|
struct sctp_shared_key *key;
|
|
struct list_head *sh_keys;
|
|
int found = 0;
|
|
|
|
/* The key identifier MUST NOT be the current active key
|
|
* The key identifier MUST correst to an existing key
|
|
*/
|
|
if (asoc) {
|
|
if (asoc->active_key_id == key_id)
|
|
return -EINVAL;
|
|
|
|
sh_keys = &asoc->endpoint_shared_keys;
|
|
} else {
|
|
if (ep->active_key_id == key_id)
|
|
return -EINVAL;
|
|
|
|
sh_keys = &ep->endpoint_shared_keys;
|
|
}
|
|
|
|
key_for_each(key, sh_keys) {
|
|
if (key->key_id == key_id) {
|
|
found = 1;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (!found)
|
|
return -EINVAL;
|
|
|
|
/* Delete the shared key */
|
|
list_del_init(&key->key_list);
|
|
sctp_auth_shkey_free(key);
|
|
|
|
return 0;
|
|
}
|