X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=net%2Fsctp%2Finput.c;h=ca6b022b1df247f93d058b5cdee5c5430f52e286;hb=eb6d42ea17329745d7d712d3aa3bb84ec1da9c85;hp=91ae463b079b13bf62c89fa7d8e7529e7af85685;hpb=41f81e88e01eb959f439f8537c58078e4bfc5291;p=linux-2.6 diff --git a/net/sctp/input.c b/net/sctp/input.c index 91ae463b07..ca6b022b1d 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -1,4 +1,4 @@ -/* SCTP kernel reference Implementation +/* SCTP kernel implementation * Copyright (c) 1999-2000 Cisco, Inc. * Copyright (c) 1999-2001 Motorola, Inc. * Copyright (c) 2001-2003 International Business Machines, Corp. @@ -6,17 +6,17 @@ * Copyright (c) 2001 Nokia, Inc. * Copyright (c) 2001 La Monte H.P. Yarroll * - * This file is part of the SCTP kernel reference Implementation + * This file is part of the SCTP kernel implementation * * These functions handle all input from the IP layer into SCTP. * - * The SCTP reference implementation is free software; + * 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. * - * The SCTP reference implementation is distributed in the hope that it + * 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. @@ -60,6 +60,7 @@ #include #include #include +#include /* Forward declarations for internal helpers. */ static int sctp_rcv_ootb(struct sk_buff *); @@ -408,7 +409,7 @@ void sctp_icmp_proto_unreachable(struct sock *sk, struct sctp_association *asoc, struct sctp_transport *t) { - SCTP_DEBUG_PRINTK("%s\n", __FUNCTION__); + SCTP_DEBUG_PRINTK("%s\n", __func__); sctp_do_sm(SCTP_EVENT_T_OTHER, SCTP_ST_OTHER(SCTP_EVENT_ICMP_PROTO_UNREACH), @@ -724,7 +725,6 @@ static struct sctp_endpoint *__sctp_rcv_lookup_endpoint(const union sctp_addr *l } ep = sctp_sk((sctp_get_ctl_sock()))->ep; - epb = &ep->base; hit: sctp_endpoint_hold(ep); @@ -890,14 +890,6 @@ static struct sctp_association *__sctp_rcv_init_lookup(struct sk_buff *skb, ch = (sctp_chunkhdr_t *) skb->data; - /* The code below will attempt to walk the chunk and extract - * parameter information. Before we do that, we need to verify - * that the chunk length doesn't cause overflow. Otherwise, we'll - * walk off the end. - */ - if (WORD_ROUND(ntohs(ch->length)) > skb->len) - return NULL; - /* * This code will NOT touch anything inside the chunk--it is * strictly READ-ONLY. @@ -934,6 +926,44 @@ static struct sctp_association *__sctp_rcv_init_lookup(struct sk_buff *skb, return NULL; } +/* ADD-IP, Section 5.2 + * When an endpoint receives an ASCONF Chunk from the remote peer + * special procedures may be needed to identify the association the + * ASCONF Chunk is associated with. To properly find the association + * the following procedures SHOULD be followed: + * + * D2) If the association is not found, use the address found in the + * Address Parameter TLV combined with the port number found in the + * SCTP common header. If found proceed to rule D4. + * + * D2-ext) If more than one ASCONF Chunks are packed together, use the + * address found in the ASCONF Address Parameter TLV of each of the + * subsequent ASCONF Chunks. If found, proceed to rule D4. + */ +static struct sctp_association *__sctp_rcv_asconf_lookup( + sctp_chunkhdr_t *ch, + const union sctp_addr *laddr, + __be16 peer_port, + struct sctp_transport **transportp) +{ + sctp_addip_chunk_t *asconf = (struct sctp_addip_chunk *)ch; + struct sctp_af *af; + union sctp_addr_param *param; + union sctp_addr paddr; + + /* Skip over the ADDIP header and find the Address parameter */ + param = (union sctp_addr_param *)(asconf + 1); + + af = sctp_get_af_specific(param_type2af(param->v4.param_hdr.type)); + if (unlikely(!af)) + return NULL; + + af->from_addr_param(&paddr, param, peer_port, 0); + + return __sctp_lookup_association(laddr, &paddr, transportp); +} + + /* SCTP-AUTH, Section 6.3: * If the receiver does not find a STCB for a packet containing an AUTH * chunk as the first chunk and not a COOKIE-ECHO chunk as the second @@ -942,20 +972,64 @@ static struct sctp_association *__sctp_rcv_init_lookup(struct sk_buff *skb, * * This means that any chunks that can help us identify the association need * to be looked at to find this assocation. -* -* TODO: The only chunk currently defined that can do that is ASCONF, but we -* don't support that functionality yet. */ -static struct sctp_association *__sctp_rcv_auth_lookup(struct sk_buff *skb, - const union sctp_addr *paddr, +static struct sctp_association *__sctp_rcv_walk_lookup(struct sk_buff *skb, const union sctp_addr *laddr, struct sctp_transport **transportp) { - /* XXX - walk through the chunks looking for something that can - * help us find the association. INIT, and INIT-ACK are not permitted. - * That leaves ASCONF, but we don't support that yet. + struct sctp_association *asoc = NULL; + sctp_chunkhdr_t *ch; + int have_auth = 0; + unsigned int chunk_num = 1; + __u8 *ch_end; + + /* Walk through the chunks looking for AUTH or ASCONF chunks + * to help us find the association. */ - return NULL; + ch = (sctp_chunkhdr_t *) skb->data; + do { + /* Break out if chunk length is less then minimal. */ + if (ntohs(ch->length) < sizeof(sctp_chunkhdr_t)) + break; + + ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length)); + if (ch_end > skb_tail_pointer(skb)) + break; + + switch(ch->type) { + case SCTP_CID_AUTH: + have_auth = chunk_num; + break; + + case SCTP_CID_COOKIE_ECHO: + /* If a packet arrives containing an AUTH chunk as + * a first chunk, a COOKIE-ECHO chunk as the second + * chunk, and possibly more chunks after them, and + * the receiver does not have an STCB for that + * packet, then authentication is based on + * the contents of the COOKIE- ECHO chunk. + */ + if (have_auth == 1 && chunk_num == 2) + return NULL; + break; + + case SCTP_CID_ASCONF: + if (have_auth || sctp_addip_noauth) + asoc = __sctp_rcv_asconf_lookup(ch, laddr, + sctp_hdr(skb)->source, + transportp); + default: + break; + } + + if (asoc) + break; + + ch = (sctp_chunkhdr_t *) ch_end; + chunk_num++; + } while (ch_end < skb_tail_pointer(skb)); + + return asoc; } /* @@ -965,7 +1039,6 @@ static struct sctp_association *__sctp_rcv_auth_lookup(struct sk_buff *skb, * chunks. */ static struct sctp_association *__sctp_rcv_lookup_harder(struct sk_buff *skb, - const union sctp_addr *paddr, const union sctp_addr *laddr, struct sctp_transport **transportp) { @@ -973,6 +1046,14 @@ static struct sctp_association *__sctp_rcv_lookup_harder(struct sk_buff *skb, ch = (sctp_chunkhdr_t *) skb->data; + /* The code below will attempt to walk the chunk and extract + * parameter information. Before we do that, we need to verify + * that the chunk length doesn't cause overflow. Otherwise, we'll + * walk off the end. + */ + if (WORD_ROUND(ntohs(ch->length)) > skb->len) + return NULL; + /* If this is INIT/INIT-ACK look inside the chunk too. */ switch (ch->type) { case SCTP_CID_INIT: @@ -980,11 +1061,12 @@ static struct sctp_association *__sctp_rcv_lookup_harder(struct sk_buff *skb, return __sctp_rcv_init_lookup(skb, laddr, transportp); break; - case SCTP_CID_AUTH: - return __sctp_rcv_auth_lookup(skb, paddr, laddr, transportp); + default: + return __sctp_rcv_walk_lookup(skb, laddr, transportp); break; } + return NULL; } @@ -1003,7 +1085,7 @@ static struct sctp_association *__sctp_rcv_lookup(struct sk_buff *skb, * parameters within the INIT or INIT-ACK. */ if (!asoc) - asoc = __sctp_rcv_lookup_harder(skb, paddr, laddr, transportp); + asoc = __sctp_rcv_lookup_harder(skb, laddr, transportp); return asoc; }