From 131a47e31ab1a9defd50ff16b04008ab94c21c0d Mon Sep 17 00:00:00 2001 From: Vlad Yasevich Date: Sun, 16 Sep 2007 15:53:56 -0700 Subject: [PATCH] [SCTP]: Implement the Supported Extensions Parameter SCTP Supported Extenions parameter is specified in Section 4.2.7 of the ADD-IP draft (soon to be RFC). The parameter is encoded as: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Parameter Type = 0x8008 | Parameter Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | CHUNK TYPE 1 | CHUNK TYPE 2 | CHUNK TYPE 3 | CHUNK TYPE 4 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | .... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | CHUNK TYPE N | PAD | PAD | PAD | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ It contains a list of chunks that a particular SCTP extension uses. Current extensions supported are Partial Reliability (FWD-TSN) and ADD-IP (ASCONF and ASCONF-ACK). When implementing new extensions (AUTH, PKT-DROP, etc..), new chunks need to be added to this parameter. Parameter processing would be modified to negotiate support for these new features. Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- include/linux/sctp.h | 9 ++++ include/net/sctp/structs.h | 1 + net/sctp/sm_make_chunk.c | 91 +++++++++++++++++++++++++++++++++++++- 3 files changed, 99 insertions(+), 2 deletions(-) diff --git a/include/linux/sctp.h b/include/linux/sctp.h index d70df61a029..f4d717b72dd 100644 --- a/include/linux/sctp.h +++ b/include/linux/sctp.h @@ -180,6 +180,9 @@ typedef enum { SCTP_PARAM_SUPPORTED_ADDRESS_TYPES = __constant_htons(12), SCTP_PARAM_ECN_CAPABLE = __constant_htons(0x8000), + /* Add-IP: Supported Extensions, Section 4.2 */ + SCTP_PARAM_SUPPORTED_EXT = __constant_htons(0x8008), + /* PR-SCTP Sec 3.1 */ SCTP_PARAM_FWD_TSN_SUPPORT = __constant_htons(0xc000), @@ -296,6 +299,12 @@ typedef struct sctp_adaptation_ind_param { __be32 adaptation_ind; } __attribute__((packed)) sctp_adaptation_ind_param_t; +/* ADDIP Section 4.2.7 Supported Extensions Parameter */ +typedef struct sctp_supported_ext_param { + struct sctp_paramhdr param_hdr; + __u8 chunks[0]; +} __attribute__((packed)) sctp_supported_ext_param_t; + /* RFC 2960. Section 3.3.3 Initiation Acknowledgement (INIT ACK) (2): * The INIT ACK chunk is used to acknowledge the initiation of an SCTP * association. diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index 67c91d01b63..b4812a2d3bb 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.h @@ -440,6 +440,7 @@ union sctp_params { struct sctp_ipv6addr_param *v6; union sctp_addr_param *addr; struct sctp_adaptation_ind_param *aind; + struct sctp_supported_ext_param *ext; }; /* RFC 2960. Section 3.3.5 Heartbeat. diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index d84e575f740..71cc204a9ea 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -179,6 +179,9 @@ struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc, sctp_supported_addrs_param_t sat; __be16 types[2]; sctp_adaptation_ind_param_t aiparam; + sctp_supported_ext_param_t ext_param; + int num_ext = 0; + __u8 extensions[3]; /* RFC 2960 3.3.2 Initiation (INIT) (1) * @@ -202,11 +205,31 @@ struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc, chunksize = sizeof(init) + addrs_len + SCTP_SAT_LEN(num_types); chunksize += sizeof(ecap_param); - if (sctp_prsctp_enable) + if (sctp_prsctp_enable) { chunksize += sizeof(prsctp_param); + extensions[num_ext] = SCTP_CID_FWD_TSN; + num_ext += 1; + } + /* ADDIP: Section 4.2.7: + * An implementation supporting this extension [ADDIP] MUST list + * the ASCONF,the ASCONF-ACK, and the AUTH chunks in its INIT and + * INIT-ACK parameters. + * XXX: We don't support AUTH just yet, so don't list it. AUTH + * support should add it. + */ + if (sctp_addip_enable) { + extensions[num_ext] = SCTP_CID_ASCONF; + extensions[num_ext+1] = SCTP_CID_ASCONF_ACK; + num_ext += 2; + } + chunksize += sizeof(aiparam); chunksize += vparam_len; + /* If we have any extensions to report, account for that */ + if (num_ext) + chunksize += sizeof(sctp_supported_ext_param_t) + num_ext; + /* RFC 2960 3.3.2 Initiation (INIT) (1) * * Note 3: An INIT chunk MUST NOT contain more than one Host @@ -241,12 +264,27 @@ struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc, sctp_addto_chunk(retval, num_types * sizeof(__u16), &types); sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param); + + /* Add the supported extensions paramter. Be nice and add this + * fist before addiding the parameters for the extensions themselves + */ + if (num_ext) { + ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT; + ext_param.param_hdr.length = + htons(sizeof(sctp_supported_ext_param_t) + num_ext); + sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t), + &ext_param); + sctp_addto_chunk(retval, num_ext, extensions); + } + if (sctp_prsctp_enable) sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param); + aiparam.param_hdr.type = SCTP_PARAM_ADAPTATION_LAYER_IND; aiparam.param_hdr.length = htons(sizeof(aiparam)); aiparam.adaptation_ind = htonl(sp->adaptation_ind); sctp_addto_chunk(retval, sizeof(aiparam), &aiparam); + nodata: kfree(addrs.v); return retval; @@ -264,6 +302,9 @@ struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc, int cookie_len; size_t chunksize; sctp_adaptation_ind_param_t aiparam; + sctp_supported_ext_param_t ext_param; + int num_ext = 0; + __u8 extensions[3]; retval = NULL; @@ -294,9 +335,19 @@ struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc, chunksize += sizeof(ecap_param); /* Tell peer that we'll do PR-SCTP only if peer advertised. */ - if (asoc->peer.prsctp_capable) + if (asoc->peer.prsctp_capable) { chunksize += sizeof(prsctp_param); + extensions[num_ext] = SCTP_CID_FWD_TSN; + num_ext += 1; + } + if (sctp_addip_enable) { + extensions[num_ext] = SCTP_CID_ASCONF; + extensions[num_ext+1] = SCTP_CID_ASCONF_ACK; + num_ext += 2; + } + + chunksize += sizeof(ext_param) + num_ext; chunksize += sizeof(aiparam); /* Now allocate and fill out the chunk. */ @@ -314,6 +365,14 @@ struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc, sctp_addto_chunk(retval, cookie_len, cookie); if (asoc->peer.ecn_capable) sctp_addto_chunk(retval, sizeof(ecap_param), &ecap_param); + if (num_ext) { + ext_param.param_hdr.type = SCTP_PARAM_SUPPORTED_EXT; + ext_param.param_hdr.length = + htons(sizeof(sctp_supported_ext_param_t) + num_ext); + sctp_addto_chunk(retval, sizeof(sctp_supported_ext_param_t), + &ext_param); + sctp_addto_chunk(retval, num_ext, extensions); + } if (asoc->peer.prsctp_capable) sctp_addto_chunk(retval, sizeof(prsctp_param), &prsctp_param); @@ -1664,6 +1723,28 @@ static int sctp_process_hn_param(const struct sctp_association *asoc, return 0; } +static void sctp_process_ext_param(struct sctp_association *asoc, + union sctp_params param) +{ + __u16 num_ext = ntohs(param.p->length) - sizeof(sctp_paramhdr_t); + int i; + + for (i = 0; i < num_ext; i++) { + switch (param.ext->chunks[i]) { + case SCTP_CID_FWD_TSN: + if (sctp_prsctp_enable && + !asoc->peer.prsctp_capable) + asoc->peer.prsctp_capable = 1; + break; + case SCTP_CID_ASCONF: + case SCTP_CID_ASCONF_ACK: + /* don't need to do anything for ASCONF */ + default: + break; + } + } +} + /* RFC 3.2.1 & the Implementers Guide 2.2. * * The Parameter Types are encoded such that the @@ -1780,11 +1861,13 @@ static int sctp_verify_param(const struct sctp_association *asoc, case SCTP_PARAM_UNRECOGNIZED_PARAMETERS: case SCTP_PARAM_ECN_CAPABLE: case SCTP_PARAM_ADAPTATION_LAYER_IND: + case SCTP_PARAM_SUPPORTED_EXT: break; 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); + case SCTP_PARAM_FWD_TSN_SUPPORT: if (sctp_prsctp_enable) break; @@ -2129,6 +2212,10 @@ static int sctp_process_param(struct sctp_association *asoc, asoc->peer.adaptation_ind = param.aind->adaptation_ind; break; + case SCTP_PARAM_SUPPORTED_EXT: + sctp_process_ext_param(asoc, param); + break; + case SCTP_PARAM_FWD_TSN_SUPPORT: if (sctp_prsctp_enable) { asoc->peer.prsctp_capable = 1; -- 2.41.1