| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 7 Nov 2007 12:46:28 -0500
From: Vlad Yasevich <vladislav.yasevich@...com>
To: davem@...emloft.net
Cc: netdev@...r.kernel.org, lksctp-developers@...ts.sourceforge.net,
Vlad Yasevich <vladislav.yasevich@...com>
Subject: [PATCH 10/13] SCTP: Make sctp_verify_param return multiple indications.
SCTP-AUTH and future ADD-IP updates have a requirement to
do additional verification of parameters and an ability to
ABORT the association if verification fails. So, introduce
additional return code so that we can clearly signal a required
action.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@...com>
---
include/net/sctp/constants.h | 2 +
net/sctp/sm_make_chunk.c | 149 +++++++++++++++++++++---------------------
2 files changed, 77 insertions(+), 74 deletions(-)
diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h
index 73fbdf6..f30b537 100644
--- a/include/net/sctp/constants.h
+++ b/include/net/sctp/constants.h
@@ -186,6 +186,8 @@ typedef enum {
SCTP_IERROR_AUTH_BAD_HMAC,
SCTP_IERROR_AUTH_BAD_KEYID,
SCTP_IERROR_PROTO_VIOLATION,
+ SCTP_IERROR_ERROR,
+ SCTP_IERROR_ABORT,
} sctp_ierror_t;
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 43e8de1..5a9783c 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -1788,9 +1788,14 @@ static int sctp_process_inv_paramlength(const struct sctp_association *asoc,
sizeof(sctp_paramhdr_t);
+ /* This is a fatal error. Any accumulated non-fatal errors are
+ * not reported.
+ */
+ if (*errp)
+ sctp_chunk_free(*errp);
+
/* Create an error chunk and fill it in with our payload. */
- if (!*errp)
- *errp = sctp_make_op_error_space(asoc, chunk, payload_len);
+ *errp = sctp_make_op_error_space(asoc, chunk, payload_len);
if (*errp) {
sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION,
@@ -1813,9 +1818,15 @@ static int sctp_process_hn_param(const struct sctp_association *asoc,
{
__u16 len = ntohs(param.p->length);
- /* Make an ERROR chunk. */
- if (!*errp)
- *errp = sctp_make_op_error_space(asoc, chunk, len);
+ /* Processing of the HOST_NAME parameter will generate an
+ * ABORT. If we've accumulated any non-fatal errors, they
+ * would be unrecognized parameters and we should not include
+ * them in the ABORT.
+ */
+ if (*errp)
+ sctp_chunk_free(*errp);
+
+ *errp = sctp_make_op_error_space(asoc, chunk, len);
if (*errp) {
sctp_init_cause(*errp, SCTP_ERROR_DNS_FAILED, len);
@@ -1862,56 +1873,40 @@ static void sctp_process_ext_param(struct sctp_association *asoc,
* taken if the processing endpoint does not recognize the
* Parameter Type.
*
- * 00 - Stop processing this SCTP chunk and discard it,
- * do not process any further chunks within it.
+ * 00 - Stop processing this parameter; do not process any further
+ * parameters within this chunk
*
- * 01 - Stop processing this SCTP chunk and discard it,
- * do not process any further chunks within it, and report
- * the unrecognized parameter in an 'Unrecognized
- * Parameter Type' (in either an ERROR or in the INIT ACK).
+ * 01 - Stop processing this parameter, do not process any further
+ * parameters within this chunk, and report the unrecognized
+ * parameter in an 'Unrecognized Parameter' ERROR chunk.
*
* 10 - Skip this parameter and continue processing.
*
* 11 - Skip this parameter and continue processing but
* report the unrecognized parameter in an
- * 'Unrecognized Parameter Type' (in either an ERROR or in
- * the INIT ACK).
+ * 'Unrecognized Parameter' ERROR chunk.
*
* Return value:
- * 0 - discard the chunk
- * 1 - continue with the chunk
+ * SCTP_IERROR_NO_ERROR - continue with the chunk
+ * SCTP_IERROR_ERROR - stop and report an error.
+ * SCTP_IERROR_NOMEME - out of memory.
*/
-static int sctp_process_unk_param(const struct sctp_association *asoc,
- union sctp_params param,
- struct sctp_chunk *chunk,
- struct sctp_chunk **errp)
+static sctp_ierror_t sctp_process_unk_param(const struct sctp_association *asoc,
+ union sctp_params param,
+ struct sctp_chunk *chunk,
+ struct sctp_chunk **errp)
{
- int retval = 1;
+ int retval = SCTP_IERROR_NO_ERROR;
switch (param.p->type & SCTP_PARAM_ACTION_MASK) {
case SCTP_PARAM_ACTION_DISCARD:
- retval = 0;
- break;
- case SCTP_PARAM_ACTION_DISCARD_ERR:
- retval = 0;
- /* Make an ERROR chunk, preparing enough room for
- * returning multiple unknown parameters.
- */
- if (NULL == *errp)
- *errp = sctp_make_op_error_space(asoc, chunk,
- ntohs(chunk->chunk_hdr->length));
-
- if (*errp) {
- sctp_init_cause(*errp, SCTP_ERROR_UNKNOWN_PARAM,
- WORD_ROUND(ntohs(param.p->length)));
- sctp_addto_chunk(*errp,
- WORD_ROUND(ntohs(param.p->length)),
- param.v);
- }
-
+ retval = SCTP_IERROR_ERROR;
break;
case SCTP_PARAM_ACTION_SKIP:
break;
+ case SCTP_PARAM_ACTION_DISCARD_ERR:
+ retval = SCTP_IERROR_ERROR;
+ /* Fall through */
case SCTP_PARAM_ACTION_SKIP_ERR:
/* Make an ERROR chunk, preparing enough room for
* returning multiple unknown parameters.
@@ -1932,9 +1927,8 @@ static int sctp_process_unk_param(const struct sctp_association *asoc,
* to the peer and the association won't be
* established.
*/
- retval = 0;
+ retval = SCTP_IERROR_NOMEM;
}
-
break;
default:
break;
@@ -1943,18 +1937,20 @@ static int sctp_process_unk_param(const struct sctp_association *asoc,
return retval;
}
-/* Find unrecognized parameters in the chunk.
+/* Verify variable length parameters
* Return values:
- * 0 - discard the chunk
- * 1 - continue with the chunk
+ * SCTP_IERROR_ABORT - trigger an ABORT
+ * SCTP_IERROR_NOMEM - out of memory (abort)
+ * SCTP_IERROR_ERROR - stop processing, trigger an ERROR
+ * SCTP_IERROR_NO_ERROR - continue with the chunk
*/
-static int sctp_verify_param(const struct sctp_association *asoc,
- union sctp_params param,
- sctp_cid_t cid,
- struct sctp_chunk *chunk,
- struct sctp_chunk **err_chunk)
+static sctp_ierror_t sctp_verify_param(const struct sctp_association *asoc,
+ union sctp_params param,
+ sctp_cid_t cid,
+ struct sctp_chunk *chunk,
+ struct sctp_chunk **err_chunk)
{
- int retval = 1;
+ int retval = SCTP_IERROR_NO_ERROR;
/* FIXME - This routine is not looking at each parameter per the
* chunk type, i.e., unrecognized parameters should be further
@@ -1976,7 +1972,9 @@ static int sctp_verify_param(const struct sctp_association *asoc,
case SCTP_PARAM_HOST_NAME_ADDRESS:
/* Tell the peer, we won't support this param. */
- return sctp_process_hn_param(asoc, param, chunk, err_chunk);
+ sctp_process_hn_param(asoc, param, chunk, err_chunk);
+ retval = SCTP_IERROR_ABORT;
+ break;
case SCTP_PARAM_FWD_TSN_SUPPORT:
if (sctp_prsctp_enable)
@@ -1993,9 +1991,11 @@ static int sctp_verify_param(const struct sctp_association *asoc,
* cause 'Protocol Violation'.
*/
if (SCTP_AUTH_RANDOM_LENGTH !=
- ntohs(param.p->length) - sizeof(sctp_paramhdr_t))
- return sctp_process_inv_paramlength(asoc, param.p,
+ ntohs(param.p->length) - sizeof(sctp_paramhdr_t)) {
+ sctp_process_inv_paramlength(asoc, param.p,
chunk, err_chunk);
+ retval = SCTP_IERROR_ABORT;
+ }
break;
case SCTP_PARAM_CHUNKS:
@@ -2007,9 +2007,11 @@ static int sctp_verify_param(const struct sctp_association *asoc,
* INIT-ACK chunk if the sender wants to receive authenticated
* chunks. Its maximum length is 260 bytes.
*/
- if (260 < ntohs(param.p->length))
- return sctp_process_inv_paramlength(asoc, param.p,
- chunk, err_chunk);
+ if (260 < ntohs(param.p->length)) {
+ sctp_process_inv_paramlength(asoc, param.p,
+ chunk, err_chunk);
+ retval = SCTP_IERROR_ABORT;
+ }
break;
case SCTP_PARAM_HMAC_ALGO:
@@ -2020,8 +2022,7 @@ fallthrough:
default:
SCTP_DEBUG_PRINTK("Unrecognized param: %d for chunk %d.\n",
ntohs(param.p->type), cid);
- return sctp_process_unk_param(asoc, param, chunk, err_chunk);
-
+ retval = sctp_process_unk_param(asoc, param, chunk, err_chunk);
break;
}
return retval;
@@ -2036,6 +2037,7 @@ int sctp_verify_init(const struct sctp_association *asoc,
{
union sctp_params param;
int has_cookie = 0;
+ int result;
/* Verify stream values are non-zero. */
if ((0 == peer_init->init_hdr.num_outbound_streams) ||
@@ -2043,8 +2045,7 @@ int sctp_verify_init(const struct sctp_association *asoc,
(0 == peer_init->init_hdr.init_tag) ||
(SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
- sctp_process_inv_mandatory(asoc, chunk, errp);
- return 0;
+ return sctp_process_inv_mandatory(asoc, chunk, errp);
}
/* Check for missing mandatory parameters. */
@@ -2062,29 +2063,29 @@ int sctp_verify_init(const struct sctp_association *asoc,
* VIOLATION error. We build the ERROR chunk here and let the normal
* error handling code build and send the packet.
*/
- if (param.v != (void*)chunk->chunk_end) {
- sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
- return 0;
- }
+ if (param.v != (void*)chunk->chunk_end)
+ return sctp_process_inv_paramlength(asoc, param.p, chunk, errp);
/* The only missing mandatory param possible today is
* the state cookie for an INIT-ACK chunk.
*/
- if ((SCTP_CID_INIT_ACK == cid) && !has_cookie) {
- sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
- chunk, errp);
- return 0;
- }
-
- /* Find unrecognized parameters. */
+ if ((SCTP_CID_INIT_ACK == cid) && !has_cookie)
+ return sctp_process_missing_param(asoc, SCTP_PARAM_STATE_COOKIE,
+ chunk, errp);
+ /* Verify all the variable length parameters */
sctp_walk_params(param, peer_init, init_hdr.params) {
- if (!sctp_verify_param(asoc, param, cid, chunk, errp)) {
- if (SCTP_PARAM_HOST_NAME_ADDRESS == param.p->type)
+ result = sctp_verify_param(asoc, param, cid, chunk, errp);
+ switch (result) {
+ case SCTP_IERROR_ABORT:
+ case SCTP_IERROR_NOMEM:
return 0;
- else
+ case SCTP_IERROR_ERROR:
return 1;
+ case SCTP_IERROR_NO_ERROR:
+ default:
+ break;
}
} /* for (loop through all parameters) */
--
1.5.2.4
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists