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-rw-r--r--net/sctp/associola.c30
-rw-r--r--net/sctp/sm_statefuns.c86
2 files changed, 75 insertions, 41 deletions
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 837806dd5799..a47179da24e6 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -1024,8 +1024,9 @@ static void sctp_assoc_bh_rcv(struct work_struct *work)
struct sctp_endpoint *ep;
struct sctp_chunk *chunk;
struct sctp_inq *inqueue;
- int state;
+ int first_time = 1; /* is this the first time through the loop */
int error = 0;
+ int state;
/* The association should be held so we should be safe. */
ep = asoc->ep;
@@ -1036,6 +1037,30 @@ static void sctp_assoc_bh_rcv(struct work_struct *work)
state = asoc->state;
subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
+ /* If the first chunk in the packet is AUTH, do special
+ * processing specified in Section 6.3 of SCTP-AUTH spec
+ */
+ if (first_time && subtype.chunk == SCTP_CID_AUTH) {
+ struct sctp_chunkhdr *next_hdr;
+
+ next_hdr = sctp_inq_peek(inqueue);
+ if (!next_hdr)
+ goto normal;
+
+ /* If the next chunk is COOKIE-ECHO, skip the AUTH
+ * chunk while saving a pointer to it so we can do
+ * Authentication later (during cookie-echo
+ * processing).
+ */
+ if (next_hdr->type == SCTP_CID_COOKIE_ECHO) {
+ chunk->auth_chunk = skb_clone(chunk->skb,
+ GFP_ATOMIC);
+ chunk->auth = 1;
+ continue;
+ }
+ }
+
+normal:
/* SCTP-AUTH, Section 6.3:
* The receiver has a list of chunk types which it expects
* to be received only after an AUTH-chunk. This list has
@@ -1074,6 +1099,9 @@ static void sctp_assoc_bh_rcv(struct work_struct *work)
/* If there is an error on chunk, discard this packet. */
if (error && chunk)
chunk->pdiscard = 1;
+
+ if (first_time)
+ first_time = 0;
}
sctp_association_put(asoc);
}
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 28c070e187c2..c9ae3404b1bb 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -153,10 +153,7 @@ static enum sctp_disposition sctp_sf_violation_chunk(
struct sctp_cmd_seq *commands);
static enum sctp_ierror sctp_sf_authenticate(
- struct net *net,
- const struct sctp_endpoint *ep,
const struct sctp_association *asoc,
- const union sctp_subtype type,
struct sctp_chunk *chunk);
static enum sctp_disposition __sctp_sf_do_9_1_abort(
@@ -626,6 +623,38 @@ enum sctp_disposition sctp_sf_do_5_1C_ack(struct net *net,
return SCTP_DISPOSITION_CONSUME;
}
+static bool sctp_auth_chunk_verify(struct net *net, struct sctp_chunk *chunk,
+ const struct sctp_association *asoc)
+{
+ struct sctp_chunk auth;
+
+ if (!chunk->auth_chunk)
+ return true;
+
+ /* SCTP-AUTH: auth_chunk pointer is only set when the cookie-echo
+ * is supposed to be authenticated and we have to do delayed
+ * authentication. We've just recreated the association using
+ * the information in the cookie and now it's much easier to
+ * do the authentication.
+ */
+
+ /* Make sure that we and the peer are AUTH capable */
+ if (!net->sctp.auth_enable || !asoc->peer.auth_capable)
+ return false;
+
+ /* set-up our fake chunk so that we can process it */
+ auth.skb = chunk->auth_chunk;
+ auth.asoc = chunk->asoc;
+ auth.sctp_hdr = chunk->sctp_hdr;
+ auth.chunk_hdr = (struct sctp_chunkhdr *)
+ skb_push(chunk->auth_chunk,
+ sizeof(struct sctp_chunkhdr));
+ skb_pull(chunk->auth_chunk, sizeof(struct sctp_chunkhdr));
+ auth.transport = chunk->transport;
+
+ return sctp_sf_authenticate(asoc, &auth) == SCTP_IERROR_NO_ERROR;
+}
+
/*
* Respond to a normal COOKIE ECHO chunk.
* We are the side that is being asked for an association.
@@ -763,37 +792,9 @@ enum sctp_disposition sctp_sf_do_5_1D_ce(struct net *net,
if (error)
goto nomem_init;
- /* SCTP-AUTH: auth_chunk pointer is only set when the cookie-echo
- * is supposed to be authenticated and we have to do delayed
- * authentication. We've just recreated the association using
- * the information in the cookie and now it's much easier to
- * do the authentication.
- */
- if (chunk->auth_chunk) {
- struct sctp_chunk auth;
- enum sctp_ierror ret;
-
- /* Make sure that we and the peer are AUTH capable */
- if (!net->sctp.auth_enable || !new_asoc->peer.auth_capable) {
- sctp_association_free(new_asoc);
- return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
- }
-
- /* set-up our fake chunk so that we can process it */
- auth.skb = chunk->auth_chunk;
- auth.asoc = chunk->asoc;
- auth.sctp_hdr = chunk->sctp_hdr;
- auth.chunk_hdr = (struct sctp_chunkhdr *)
- skb_push(chunk->auth_chunk,
- sizeof(struct sctp_chunkhdr));
- skb_pull(chunk->auth_chunk, sizeof(struct sctp_chunkhdr));
- auth.transport = chunk->transport;
-
- ret = sctp_sf_authenticate(net, ep, new_asoc, type, &auth);
- if (ret != SCTP_IERROR_NO_ERROR) {
- sctp_association_free(new_asoc);
- return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
- }
+ if (!sctp_auth_chunk_verify(net, chunk, new_asoc)) {
+ sctp_association_free(new_asoc);
+ return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands);
}
repl = sctp_make_cookie_ack(new_asoc, chunk);
@@ -1797,13 +1798,15 @@ static enum sctp_disposition sctp_sf_do_dupcook_a(
if (sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC))
goto nomem;
+ if (!sctp_auth_chunk_verify(net, chunk, new_asoc))
+ return SCTP_DISPOSITION_DISCARD;
+
/* Make sure no new addresses are being added during the
* restart. Though this is a pretty complicated attack
* since you'd have to get inside the cookie.
*/
- if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, commands)) {
+ if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk, commands))
return SCTP_DISPOSITION_CONSUME;
- }
/* If the endpoint is in the SHUTDOWN-ACK-SENT state and recognizes
* the peer has restarted (Action A), it MUST NOT setup a new
@@ -1912,6 +1915,9 @@ static enum sctp_disposition sctp_sf_do_dupcook_b(
if (sctp_auth_asoc_init_active_key(new_asoc, GFP_ATOMIC))
goto nomem;
+ if (!sctp_auth_chunk_verify(net, chunk, new_asoc))
+ return SCTP_DISPOSITION_DISCARD;
+
/* Update the content of current association. */
sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc));
sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
@@ -2009,6 +2015,9 @@ static enum sctp_disposition sctp_sf_do_dupcook_d(
* a COOKIE ACK.
*/
+ if (!sctp_auth_chunk_verify(net, chunk, asoc))
+ return SCTP_DISPOSITION_DISCARD;
+
/* Don't accidentally move back into established state. */
if (asoc->state < SCTP_STATE_ESTABLISHED) {
sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
@@ -4171,10 +4180,7 @@ gen_shutdown:
* The return value is the disposition of the chunk.
*/
static enum sctp_ierror sctp_sf_authenticate(
- struct net *net,
- const struct sctp_endpoint *ep,
const struct sctp_association *asoc,
- const union sctp_subtype type,
struct sctp_chunk *chunk)
{
struct sctp_shared_key *sh_key = NULL;
@@ -4275,7 +4281,7 @@ enum sctp_disposition sctp_sf_eat_auth(struct net *net,
commands);
auth_hdr = (struct sctp_authhdr *)chunk->skb->data;
- error = sctp_sf_authenticate(net, ep, asoc, type, chunk);
+ error = sctp_sf_authenticate(asoc, chunk);
switch (error) {
case SCTP_IERROR_AUTH_BAD_HMAC:
/* Generate the ERROR chunk and discard the rest