From: Vlad Yasevich Date: Fri, 9 Nov 2007 16:43:41 +0000 (-0500) Subject: SCTP: Make sctp_verify_param return multiple indications. X-Git-Tag: v2.6.24-rc3~145^2~27^2~4 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7ab9080467040054e27ae54d67cc185f24d881ae;p=linux-2.6 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 clear signal a required action. Signed-off-by: Vlad Yasevich --- diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h index 73fbdf6a24..f30b537d69 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 43e8de1228..5a9783c38d 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) */