From b7e10c25b839c0c7579b2b402afc9883c107e09f Mon Sep 17 00:00:00 2001 From: Richard Haines Date: Sat, 24 Feb 2018 16:18:51 +0000 Subject: sctp: Add ip option support Add ip option support to allow LSM security modules to utilise CIPSO/IPv4 and CALIPSO/IPv6 services. Signed-off-by: Richard Haines Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: Paul Moore --- net/sctp/chunk.c | 10 +++++++--- net/sctp/ipv6.c | 45 ++++++++++++++++++++++++++++++++++++++------- net/sctp/output.c | 34 +++++++++++++++++++++------------- net/sctp/protocol.c | 43 +++++++++++++++++++++++++++++++++++++++++++ net/sctp/socket.c | 11 ++++++++--- 5 files changed, 117 insertions(+), 26 deletions(-) (limited to 'net/sctp') diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c index 991a530c6b31..d726d213de9a 100644 --- a/net/sctp/chunk.c +++ b/net/sctp/chunk.c @@ -171,6 +171,8 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc, struct list_head *pos, *temp; struct sctp_chunk *chunk; struct sctp_datamsg *msg; + struct sctp_sock *sp; + struct sctp_af *af; int err; msg = sctp_datamsg_new(GFP_KERNEL); @@ -189,9 +191,11 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc, /* This is the biggest possible DATA chunk that can fit into * the packet */ - max_data = asoc->pathmtu - - sctp_sk(asoc->base.sk)->pf->af->net_header_len - - sizeof(struct sctphdr) - sctp_datachk_len(&asoc->stream); + sp = sctp_sk(asoc->base.sk); + af = sp->pf->af; + max_data = asoc->pathmtu - af->net_header_len - + sizeof(struct sctphdr) - sctp_datachk_len(&asoc->stream) - + af->ip_options_len(asoc->base.sk); max_data = SCTP_TRUNC4(max_data); /* If the the peer requested that we authenticate DATA chunks diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c index e35d4f73d2df..30a05a80262e 100644 --- a/net/sctp/ipv6.c +++ b/net/sctp/ipv6.c @@ -427,6 +427,41 @@ static void sctp_v6_copy_addrlist(struct list_head *addrlist, rcu_read_unlock(); } +/* Copy over any ip options */ +static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk) +{ + struct ipv6_pinfo *newnp, *np = inet6_sk(sk); + struct ipv6_txoptions *opt; + + newnp = inet6_sk(newsk); + + rcu_read_lock(); + opt = rcu_dereference(np->opt); + if (opt) { + opt = ipv6_dup_options(newsk, opt); + if (!opt) + pr_err("%s: Failed to copy ip options\n", __func__); + } + RCU_INIT_POINTER(newnp->opt, opt); + rcu_read_unlock(); +} + +/* Account for the IP options */ +static int sctp_v6_ip_options_len(struct sock *sk) +{ + struct ipv6_pinfo *np = inet6_sk(sk); + struct ipv6_txoptions *opt; + int len = 0; + + rcu_read_lock(); + opt = rcu_dereference(np->opt); + if (opt) + len = opt->opt_flen + opt->opt_nflen; + + rcu_read_unlock(); + return len; +} + /* Initialize a sockaddr_storage from in incoming skb. */ static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb, int is_saddr) @@ -666,7 +701,6 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk, struct sock *newsk; struct ipv6_pinfo *newnp, *np = inet6_sk(sk); struct sctp6_sock *newsctp6sk; - struct ipv6_txoptions *opt; newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern); if (!newsk) @@ -689,12 +723,7 @@ static struct sock *sctp_v6_create_accept_sk(struct sock *sk, newnp->ipv6_ac_list = NULL; newnp->ipv6_fl_list = NULL; - rcu_read_lock(); - opt = rcu_dereference(np->opt); - if (opt) - opt = ipv6_dup_options(newsk, opt); - RCU_INIT_POINTER(newnp->opt, opt); - rcu_read_unlock(); + sctp_v6_copy_ip_options(sk, newsk); /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() * and getpeername(). @@ -1041,6 +1070,7 @@ static struct sctp_af sctp_af_inet6 = { .ecn_capable = sctp_v6_ecn_capable, .net_header_len = sizeof(struct ipv6hdr), .sockaddr_len = sizeof(struct sockaddr_in6), + .ip_options_len = sctp_v6_ip_options_len, #ifdef CONFIG_COMPAT .compat_setsockopt = compat_ipv6_setsockopt, .compat_getsockopt = compat_ipv6_getsockopt, @@ -1059,6 +1089,7 @@ static struct sctp_pf sctp_pf_inet6 = { .addr_to_user = sctp_v6_addr_to_user, .to_sk_saddr = sctp_v6_to_sk_saddr, .to_sk_daddr = sctp_v6_to_sk_daddr, + .copy_ip_options = sctp_v6_copy_ip_options, .af = &sctp_af_inet6, }; diff --git a/net/sctp/output.c b/net/sctp/output.c index 01a26ee051e3..a58d13c2d443 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -69,7 +69,11 @@ static enum sctp_xmit sctp_packet_will_fit(struct sctp_packet *packet, static void sctp_packet_reset(struct sctp_packet *packet) { + /* sctp_packet_transmit() relies on this to reset size to the + * current overhead after sending packets. + */ packet->size = packet->overhead; + packet->has_cookie_echo = 0; packet->has_sack = 0; packet->has_data = 0; @@ -87,6 +91,7 @@ void sctp_packet_config(struct sctp_packet *packet, __u32 vtag, struct sctp_transport *tp = packet->transport; struct sctp_association *asoc = tp->asoc; struct sock *sk; + size_t overhead = sizeof(struct ipv6hdr) + sizeof(struct sctphdr); pr_debug("%s: packet:%p vtag:0x%x\n", __func__, packet, vtag); packet->vtag = vtag; @@ -95,10 +100,22 @@ void sctp_packet_config(struct sctp_packet *packet, __u32 vtag, if (!sctp_packet_empty(packet)) return; - /* set packet max_size with pathmtu */ + /* set packet max_size with pathmtu, then calculate overhead */ packet->max_size = tp->pathmtu; - if (!asoc) + if (asoc) { + struct sctp_sock *sp = sctp_sk(asoc->base.sk); + struct sctp_af *af = sp->pf->af; + + overhead = af->net_header_len + + af->ip_options_len(asoc->base.sk); + overhead += sizeof(struct sctphdr); + packet->overhead = overhead; + packet->size = overhead; + } else { + packet->overhead = overhead; + packet->size = overhead; return; + } /* update dst or transport pathmtu if in need */ sk = asoc->base.sk; @@ -140,23 +157,14 @@ void sctp_packet_init(struct sctp_packet *packet, struct sctp_transport *transport, __u16 sport, __u16 dport) { - struct sctp_association *asoc = transport->asoc; - size_t overhead; - pr_debug("%s: packet:%p transport:%p\n", __func__, packet, transport); packet->transport = transport; packet->source_port = sport; packet->destination_port = dport; INIT_LIST_HEAD(&packet->chunk_list); - if (asoc) { - struct sctp_sock *sp = sctp_sk(asoc->base.sk); - overhead = sp->pf->af->net_header_len; - } else { - overhead = sizeof(struct ipv6hdr); - } - overhead += sizeof(struct sctphdr); - packet->overhead = overhead; + /* The overhead will be calculated by sctp_packet_config() */ + packet->overhead = 0; sctp_packet_reset(packet); packet->vtag = 0; } diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index 91813e686c67..02f23ad7160c 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -237,6 +237,45 @@ int sctp_copy_local_addr_list(struct net *net, struct sctp_bind_addr *bp, return error; } +/* Copy over any ip options */ +static void sctp_v4_copy_ip_options(struct sock *sk, struct sock *newsk) +{ + struct inet_sock *newinet, *inet = inet_sk(sk); + struct ip_options_rcu *inet_opt, *newopt = NULL; + + newinet = inet_sk(newsk); + + rcu_read_lock(); + inet_opt = rcu_dereference(inet->inet_opt); + if (inet_opt) { + newopt = sock_kmalloc(newsk, sizeof(*inet_opt) + + inet_opt->opt.optlen, GFP_ATOMIC); + if (newopt) + memcpy(newopt, inet_opt, sizeof(*inet_opt) + + inet_opt->opt.optlen); + else + pr_err("%s: Failed to copy ip options\n", __func__); + } + RCU_INIT_POINTER(newinet->inet_opt, newopt); + rcu_read_unlock(); +} + +/* Account for the IP options */ +static int sctp_v4_ip_options_len(struct sock *sk) +{ + struct inet_sock *inet = inet_sk(sk); + struct ip_options_rcu *inet_opt; + int len = 0; + + rcu_read_lock(); + inet_opt = rcu_dereference(inet->inet_opt); + if (inet_opt) + len = inet_opt->opt.optlen; + + rcu_read_unlock(); + return len; +} + /* Initialize a sctp_addr from in incoming skb. */ static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb, int is_saddr) @@ -588,6 +627,8 @@ static struct sock *sctp_v4_create_accept_sk(struct sock *sk, sctp_copy_sock(newsk, sk, asoc); sock_reset_flag(newsk, SOCK_ZAPPED); + sctp_v4_copy_ip_options(sk, newsk); + newinet = inet_sk(newsk); newinet->inet_daddr = asoc->peer.primary_addr.v4.sin_addr.s_addr; @@ -1006,6 +1047,7 @@ static struct sctp_pf sctp_pf_inet = { .addr_to_user = sctp_v4_addr_to_user, .to_sk_saddr = sctp_v4_to_sk_saddr, .to_sk_daddr = sctp_v4_to_sk_daddr, + .copy_ip_options = sctp_v4_copy_ip_options, .af = &sctp_af_inet }; @@ -1090,6 +1132,7 @@ static struct sctp_af sctp_af_inet = { .ecn_capable = sctp_v4_ecn_capable, .net_header_len = sizeof(struct iphdr), .sockaddr_len = sizeof(struct sockaddr_in), + .ip_options_len = sctp_v4_ip_options_len, #ifdef CONFIG_COMPAT .compat_setsockopt = compat_ip_setsockopt, .compat_getsockopt = compat_ip_getsockopt, diff --git a/net/sctp/socket.c b/net/sctp/socket.c index bf271f8c2dc9..eb55c63d1990 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -3138,6 +3138,7 @@ static int sctp_setsockopt_mappedv4(struct sock *sk, char __user *optval, unsign static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned int optlen) { struct sctp_sock *sp = sctp_sk(sk); + struct sctp_af *af = sp->pf->af; struct sctp_assoc_value params; struct sctp_association *asoc; int val; @@ -3162,7 +3163,8 @@ static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned if (val) { int min_len, max_len; - min_len = SCTP_DEFAULT_MINSEGMENT - sp->pf->af->net_header_len; + min_len = SCTP_DEFAULT_MINSEGMENT - af->net_header_len; + min_len -= af->ip_options_len(sk); min_len -= sizeof(struct sctphdr) + sizeof(struct sctp_data_chunk); @@ -3175,7 +3177,8 @@ static int sctp_setsockopt_maxseg(struct sock *sk, char __user *optval, unsigned asoc = sctp_id2assoc(sk, params.assoc_id); if (asoc) { if (val == 0) { - val = asoc->pathmtu - sp->pf->af->net_header_len; + val = asoc->pathmtu - af->net_header_len; + val -= af->ip_options_len(sk); val -= sizeof(struct sctphdr) + sctp_datachk_len(&asoc->stream); } @@ -5087,9 +5090,11 @@ int sctp_do_peeloff(struct sock *sk, sctp_assoc_t id, struct socket **sockp) sctp_copy_sock(sock->sk, sk, asoc); /* Make peeled-off sockets more like 1-1 accepted sockets. - * Set the daddr and initialize id to something more random + * Set the daddr and initialize id to something more random and also + * copy over any ip options. */ sp->pf->to_sk_daddr(&asoc->peer.primary_addr, sk); + sp->pf->copy_ip_options(sk, sock->sk); /* Populate the fields of the newsk from the oldsk and migrate the * asoc to the newsk. -- cgit v1.2.3 From 2277c7cd75e39783eeb7512a6c35f8b4abbe1039 Mon Sep 17 00:00:00 2001 From: Richard Haines Date: Tue, 13 Feb 2018 20:56:24 +0000 Subject: sctp: Add LSM hooks Add security hooks allowing security modules to exercise access control over SCTP. Signed-off-by: Richard Haines Signed-off-by: Paul Moore --- net/sctp/sm_make_chunk.c | 12 ++++++++++ net/sctp/sm_statefuns.c | 18 ++++++++++++++ net/sctp/socket.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++- 3 files changed, 91 insertions(+), 1 deletion(-) (limited to 'net/sctp') diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index d01475f5f710..70274ae5ac6f 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -3071,6 +3071,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc, if (af->is_any(&addr)) memcpy(&addr, &asconf->source, sizeof(addr)); + if (security_sctp_bind_connect(asoc->ep->base.sk, + SCTP_PARAM_ADD_IP, + (struct sockaddr *)&addr, + af->sockaddr_len)) + return SCTP_ERROR_REQ_REFUSED; + /* ADDIP 4.3 D9) If an endpoint receives an ADD IP address * request and does not have the local resources to add this * new address to the association, it MUST return an Error @@ -3137,6 +3143,12 @@ static __be16 sctp_process_asconf_param(struct sctp_association *asoc, if (af->is_any(&addr)) memcpy(&addr.v4, sctp_source(asconf), sizeof(addr)); + if (security_sctp_bind_connect(asoc->ep->base.sk, + SCTP_PARAM_SET_PRIMARY, + (struct sockaddr *)&addr, + af->sockaddr_len)) + return SCTP_ERROR_REQ_REFUSED; + peer = sctp_assoc_lookup_paddr(asoc, &addr); if (!peer) return SCTP_ERROR_DNS_FAILED; diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index eb7905ffe5f2..42659ab68c38 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -321,6 +321,11 @@ enum sctp_disposition sctp_sf_do_5_1B_init(struct net *net, struct sctp_packet *packet; int len; + /* Update socket peer label if first association. */ + if (security_sctp_assoc_request((struct sctp_endpoint *)ep, + chunk->skb)) + return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); + /* 6.10 Bundling * An endpoint MUST NOT bundle INIT, INIT ACK or * SHUTDOWN COMPLETE with any other chunks. @@ -908,6 +913,9 @@ enum sctp_disposition sctp_sf_do_5_1E_ca(struct net *net, */ sctp_add_cmd_sf(commands, SCTP_CMD_INIT_COUNTER_RESET, SCTP_NULL()); + /* Set peer label for connection. */ + security_inet_conn_established(ep->base.sk, chunk->skb); + /* RFC 2960 5.1 Normal Establishment of an Association * * E) Upon reception of the COOKIE ACK, endpoint "A" will move @@ -1436,6 +1444,11 @@ static enum sctp_disposition sctp_sf_do_unexpected_init( struct sctp_packet *packet; int len; + /* Update socket peer label if first association. */ + if (security_sctp_assoc_request((struct sctp_endpoint *)ep, + chunk->skb)) + return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); + /* 6.10 Bundling * An endpoint MUST NOT bundle INIT, INIT ACK or * SHUTDOWN COMPLETE with any other chunks. @@ -2106,6 +2119,11 @@ enum sctp_disposition sctp_sf_do_5_2_4_dupcook( } } + /* Update socket peer label if first association. */ + if (security_sctp_assoc_request((struct sctp_endpoint *)ep, + chunk->skb)) + return sctp_sf_pdiscard(net, ep, asoc, type, arg, commands); + /* Set temp so that it won't be added into hashtable */ new_asoc->temp = 1; diff --git a/net/sctp/socket.c b/net/sctp/socket.c index eb55c63d1990..73b34a6b5b09 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1043,6 +1043,12 @@ static int sctp_setsockopt_bindx(struct sock *sk, /* Do the work. */ switch (op) { case SCTP_BINDX_ADD_ADDR: + /* Allow security module to validate bindx addresses. */ + err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_BINDX_ADD, + (struct sockaddr *)kaddrs, + addrs_size); + if (err) + goto out; err = sctp_bindx_add(sk, kaddrs, addrcnt); if (err) goto out; @@ -1252,6 +1258,7 @@ static int __sctp_connect(struct sock *sk, if (assoc_id) *assoc_id = asoc->assoc_id; + err = sctp_wait_for_connect(asoc, &timeo); /* Note: the asoc may be freed after the return of * sctp_wait_for_connect. @@ -1347,7 +1354,16 @@ static int __sctp_setsockopt_connectx(struct sock *sk, if (unlikely(IS_ERR(kaddrs))) return PTR_ERR(kaddrs); + /* Allow security module to validate connectx addresses. */ + err = security_sctp_bind_connect(sk, SCTP_SOCKOPT_CONNECTX, + (struct sockaddr *)kaddrs, + addrs_size); + if (err) + goto out_free; + err = __sctp_connect(sk, kaddrs, addrs_size, assoc_id); + +out_free: kvfree(kaddrs); return err; @@ -1615,6 +1631,7 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len) struct sctp_transport *transport, *chunk_tp; struct sctp_chunk *chunk; union sctp_addr to; + struct sctp_af *af; struct sockaddr *msg_name = NULL; struct sctp_sndrcvinfo default_sinfo; struct sctp_sndrcvinfo *sinfo; @@ -1844,6 +1861,24 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len) } scope = sctp_scope(&to); + + /* Label connection socket for first association 1-to-many + * style for client sequence socket()->sendmsg(). This + * needs to be done before sctp_assoc_add_peer() as that will + * set up the initial packet that needs to account for any + * security ip options (CIPSO/CALIPSO) added to the packet. + */ + af = sctp_get_af_specific(to.sa.sa_family); + if (!af) { + err = -EINVAL; + goto out_unlock; + } + err = security_sctp_bind_connect(sk, SCTP_SENDMSG_CONNECT, + (struct sockaddr *)&to, + af->sockaddr_len); + if (err < 0) + goto out_unlock; + new_asoc = sctp_association_new(ep, sk, scope, GFP_KERNEL); if (!new_asoc) { err = -ENOMEM; @@ -2909,6 +2944,8 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval, { struct sctp_prim prim; struct sctp_transport *trans; + struct sctp_af *af; + int err; if (optlen != sizeof(struct sctp_prim)) return -EINVAL; @@ -2916,6 +2953,17 @@ static int sctp_setsockopt_primary_addr(struct sock *sk, char __user *optval, if (copy_from_user(&prim, optval, sizeof(struct sctp_prim))) return -EFAULT; + /* Allow security module to validate address but need address len. */ + af = sctp_get_af_specific(prim.ssp_addr.ss_family); + if (!af) + return -EINVAL; + + err = security_sctp_bind_connect(sk, SCTP_PRIMARY_ADDR, + (struct sockaddr *)&prim.ssp_addr, + af->sockaddr_len); + if (err) + return err; + trans = sctp_addr_id2transport(sk, &prim.ssp_addr, prim.ssp_assoc_id); if (!trans) return -EINVAL; @@ -3247,6 +3295,13 @@ static int sctp_setsockopt_peer_primary_addr(struct sock *sk, char __user *optva if (!sctp_assoc_lookup_laddr(asoc, (union sctp_addr *)&prim.sspp_addr)) return -EADDRNOTAVAIL; + /* Allow security module to validate address. */ + err = security_sctp_bind_connect(sk, SCTP_SET_PEER_PRIMARY_ADDR, + (struct sockaddr *)&prim.sspp_addr, + af->sockaddr_len); + if (err) + return err; + /* Create an ASCONF chunk with SET_PRIMARY parameter */ chunk = sctp_make_asconf_set_prim(asoc, (union sctp_addr *)&prim.sspp_addr); @@ -8346,6 +8401,8 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk, { struct inet_sock *inet = inet_sk(sk); struct inet_sock *newinet; + struct sctp_sock *sp = sctp_sk(sk); + struct sctp_endpoint *ep = sp->ep; newsk->sk_type = sk->sk_type; newsk->sk_bound_dev_if = sk->sk_bound_dev_if; @@ -8388,7 +8445,10 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk, if (newsk->sk_flags & SK_FLAGS_TIMESTAMP) net_enable_timestamp(); - security_sk_clone(sk, newsk); + /* Set newsk security attributes from orginal sk and connection + * security attribute from ep. + */ + security_sctp_sk_clone(ep, sk, newsk); } static inline void sctp_copy_descendant(struct sock *sk_to, -- cgit v1.2.3