/* SCTP kernel implementation * (C) Copyright Red Hat Inc. 2017 * * This file is part of the SCTP kernel implementation * * These functions implement sctp diag support. * * 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. * * 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. * See the GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with GNU CC; see the file COPYING. If not, see * <http://www.gnu.org/licenses/>. * * Please send any bug reports or fixes you make to the * email addresched(es): * lksctp developers <linux-sctp@vger.kernel.org> * * Written or modified by: * Xin Long <lucien.xin@gmail.com> */ #include <linux/module.h> #include <linux/inet_diag.h> #include <linux/sock_diag.h> #include <net/sctp/sctp.h> static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, void *info); /* define some functions to make asoc/ep fill look clean */ static void inet_diag_msg_sctpasoc_fill(struct inet_diag_msg *r, struct sock *sk, struct sctp_association *asoc) { union sctp_addr laddr, paddr; struct dst_entry *dst; struct timer_list *t3_rtx = &asoc->peer.primary_path->T3_rtx_timer; laddr = list_entry(asoc->base.bind_addr.address_list.next, struct sctp_sockaddr_entry, list)->a; paddr = asoc->peer.primary_path->ipaddr; dst = asoc->peer.primary_path->dst; r->idiag_family = sk->sk_family; r->id.idiag_sport = htons(asoc->base.bind_addr.port); r->id.idiag_dport = htons(asoc->peer.port); r->id.idiag_if = dst ? dst->dev->ifindex : 0; sock_diag_save_cookie(sk, r->id.idiag_cookie); #if IS_ENABLED(CONFIG_IPV6) if (sk->sk_family == AF_INET6) { *(struct in6_addr *)r->id.idiag_src = laddr.v6.sin6_addr; *(struct in6_addr *)r->id.idiag_dst = paddr.v6.sin6_addr; } else #endif { memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src)); memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst)); r->id.idiag_src[0] = laddr.v4.sin_addr.s_addr; r->id.idiag_dst[0] = paddr.v4.sin_addr.s_addr; } r->idiag_state = asoc->state; if (timer_pending(t3_rtx)) { r->idiag_timer = SCTP_EVENT_TIMEOUT_T3_RTX; r->idiag_retrans = asoc->rtx_data_chunks; r->idiag_expires = jiffies_to_msecs(t3_rtx->expires - jiffies); } else { r->idiag_timer = 0; r->idiag_retrans = 0; r->idiag_expires = 0; } } static int inet_diag_msg_sctpladdrs_fill(struct sk_buff *skb, struct list_head *address_list) { struct sctp_sockaddr_entry *laddr; int addrlen = sizeof(struct sockaddr_storage); int addrcnt = 0; struct nlattr *attr; void *info = NULL; list_for_each_entry_rcu(laddr, address_list, list) addrcnt++; attr = nla_reserve(skb, INET_DIAG_LOCALS, addrlen * addrcnt); if (!attr) return -EMSGSIZE; info = nla_data(attr); list_for_each_entry_rcu(laddr, address_list, list) { memcpy(info, &laddr->a, sizeof(laddr->a)); memset(info + sizeof(laddr->a), 0, addrlen - sizeof(laddr->a)); info += addrlen; } return 0; } static int inet_diag_msg_sctpaddrs_fill(struct sk_buff *skb, struct sctp_association *asoc) { int addrlen = sizeof(struct sockaddr_storage); struct sctp_transport *from; struct nlattr *attr; void *info = NULL; attr = nla_reserve(skb, INET_DIAG_PEERS, addrlen * asoc->peer.transport_count); if (!attr) return -EMSGSIZE; info = nla_data(attr); list_for_each_entry(from, &asoc->peer.transport_addr_list, transports) { memcpy(info, &from->ipaddr, sizeof(from->ipaddr)); memset(info + sizeof(from->ipaddr), 0, addrlen - sizeof(from->ipaddr)); info += addrlen; } return 0; } /* sctp asoc/ep fill*/ static int inet_sctp_diag_fill(struct sock *sk, struct sctp_association *asoc, struct sk_buff *skb, const struct inet_diag_req_v2 *req, struct user_namespace *user_ns, int portid, u32 seq, u16 nlmsg_flags, const struct nlmsghdr *unlh, bool net_admin) { struct sctp_endpoint *ep = sctp_sk(sk)->ep; struct list_head *addr_list; struct inet_diag_msg *r; struct nlmsghdr *nlh; int ext = req->idiag_ext; struct sctp_infox infox; void *info = NULL; nlh = nlmsg_put(skb, portid, seq, unlh->nlmsg_type, sizeof(*r), nlmsg_flags); if (!nlh) return -EMSGSIZE; r = nlmsg_data(nlh); BUG_ON(!sk_fullsock(sk)); if (asoc) { inet_diag_msg_sctpasoc_fill(r, sk, asoc); } else { inet_diag_msg_common_fill(r, sk); r->idiag_state = sk->sk_state; r->idiag_timer = 0; r->idiag_retrans = 0; } if (inet_diag_msg_attrs_fill(sk, skb, r, ext, user_ns, net_admin)) goto errout; if (ext & (1 << (INET_DIAG_SKMEMINFO - 1))) { u32 mem[SK_MEMINFO_VARS]; int amt; if (asoc && asoc->ep->sndbuf_policy) amt = asoc->sndbuf_used; else amt = sk_wmem_alloc_get(sk); mem[SK_MEMINFO_WMEM_ALLOC] = amt; if (asoc && asoc->ep->rcvbuf_policy) amt = atomic_read(&asoc->rmem_alloc); else amt = sk_rmem_alloc_get(sk); mem[SK_MEMINFO_RMEM_ALLOC] = amt; mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf; mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf; mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc; mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued; mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc); mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len; mem[SK_MEMINFO_DROPS] = atomic_read(&sk->sk_drops); if (nla_put(skb, INET_DIAG_SKMEMINFO, sizeof(mem), &mem) < 0) goto errout; } if (ext & (1 << (INET_DIAG_INFO - 1))) { struct nlattr *attr; attr = nla_reserve_64bit(skb, INET_DIAG_INFO, sizeof(struct sctp_info), INET_DIAG_PAD); if (!attr) goto errout; info = nla_data(attr); } infox.sctpinfo = (struct sctp_info *)info; infox.asoc = asoc; sctp_diag_get_info(sk, r, &infox); addr_list = asoc ? &asoc->base.bind_addr.address_list : &ep->base.bind_addr.address_list; if (inet_diag_msg_sctpladdrs_fill(skb, addr_list)) goto errout; if (asoc && (ext & (1 << (INET_DIAG_CONG - 1)))) if (nla_put_string(skb, INET_DIAG_CONG, "reno") < 0) goto errout; if (asoc && inet_diag_msg_sctpaddrs_fill(skb, asoc)) goto errout; nlmsg_end(skb, nlh); return 0; errout: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } /* callback and param */ struct sctp_comm_param { struct sk_buff *skb; struct netlink_callback *cb; const struct inet_diag_req_v2 *r; const struct nlmsghdr *nlh; bool net_admin; }; static size_t inet_assoc_attr_size(struct sctp_association *asoc) { int addrlen = sizeof(struct sockaddr_storage); int addrcnt = 0; struct sctp_sockaddr_entry *laddr; list_for_each_entry_rcu(laddr, &asoc->base.bind_addr.address_list, list) addrcnt++; return nla_total_size(sizeof(struct sctp_info)) + nla_total_size(1) /* INET_DIAG_SHUTDOWN */ + nla_total_size(1) /* INET_DIAG_TOS */ + nla_total_size(1) /* INET_DIAG_TCLASS */ + nla_total_size(4) /* INET_DIAG_MARK */ + nla_total_size(addrlen * asoc->peer.transport_count) + nla_total_size(addrlen * addrcnt) + nla_total_size(sizeof(struct inet_diag_meminfo)) + nla_total_size(sizeof(struct inet_diag_msg)) + 64; } static int sctp_tsp_dump_one(struct sctp_transport *tsp, void *p) { struct sctp_association *assoc = tsp->asoc; struct sock *sk = tsp->asoc->base.sk; struct sctp_comm_param *commp = p; struct sk_buff *in_skb = commp->skb; const struct inet_diag_req_v2 *req = commp->r; const struct nlmsghdr *nlh = commp->nlh; struct net *net = sock_net(in_skb->sk); struct sk_buff *rep; int err; err = sock_diag_check_cookie(sk, req->id.idiag_cookie); if (err) goto out; err = -ENOMEM; rep = nlmsg_new(inet_assoc_attr_size(assoc), GFP_KERNEL); if (!rep) goto out; lock_sock(sk); if (sk != assoc->base.sk) { release_sock(sk); sk = assoc->base.sk; lock_sock(sk); } err = inet_sctp_diag_fill(sk, assoc, rep, req, sk_user_ns(NETLINK_CB(in_skb).sk), NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, 0, nlh, commp->net_admin); release_sock(sk); if (err < 0) { WARN_ON(err == -EMSGSIZE); kfree_skb(rep); goto out; } err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid, MSG_DONTWAIT); if (err > 0) err = 0; out: return err; } static int sctp_sock_dump(struct sctp_transport *tsp, void *p) { struct sctp_endpoint *ep = tsp->asoc->ep; struct sctp_comm_param *commp = p; struct sock *sk = ep->base.sk; struct sk_buff *skb = commp->skb; struct netlink_callback *cb = commp->cb; const struct inet_diag_req_v2 *r = commp->r; struct sctp_association *assoc; int err = 0; lock_sock(sk); list_for_each_entry(assoc, &ep->asocs, asocs) { if (cb->args[4] < cb->args[1]) goto next; if (r->id.idiag_sport != htons(assoc->base.bind_addr.port) && r->id.idiag_sport) goto next; if (r->id.idiag_dport != htons(assoc->peer.port) && r->id.idiag_dport) goto next; if (!cb->args[3] && inet_sctp_diag_fill(sk, NULL, skb, r, sk_user_ns(NETLINK_CB(cb->skb).sk), NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, commp->net_admin) < 0) { err = 1; goto release; } cb->args[3] = 1; if (inet_sctp_diag_fill(sk, assoc, skb, r, sk_user_ns(NETLINK_CB(cb->skb).sk), NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, 0, cb->nlh, commp->net_admin) < 0) { err = 1; goto release; } next: cb->args[4]++; } cb->args[1] = 0; cb->args[3] = 0; cb->args[4] = 0; release: release_sock(sk); return err; } static int sctp_sock_filter(struct sctp_transport *tsp, void *p) { struct sctp_endpoint *ep = tsp->asoc->ep; struct sctp_comm_param *commp = p; struct sock *sk = ep->base.sk; const struct inet_diag_req_v2 *r = commp->r; struct sctp_association *assoc = list_entry(ep->asocs.next, struct sctp_association, asocs); /* find the ep only once through the transports by this condition */ if (tsp->asoc != assoc) return 0; if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family) return 0; return 1; } static int sctp_ep_dump(struct sctp_endpoint *ep, void *p) { struct sctp_comm_param *commp = p; struct sock *sk = ep->base.sk; struct sk_buff *skb = commp->skb; struct netlink_callback *cb = commp->cb; const struct inet_diag_req_v2 *r = commp->r; struct net *net = sock_net(skb->sk); struct inet_sock *inet = inet_sk(sk); int err = 0; if (!net_eq(sock_net(sk), net)) goto out; if (cb->args[4] < cb->args[1]) goto next; if (!(r->idiag_states & TCPF_LISTEN) && !list_empty(&ep->asocs)) goto next; if (r->sdiag_family != AF_UNSPEC && sk->sk_family != r->sdiag_family) goto next; if (r->id.idiag_sport != inet->inet_sport && r->id.idiag_sport) goto next; if (r->id.idiag_dport != inet->inet_dport && r->id.idiag_dport) goto next; if (inet_sctp_diag_fill(sk, NULL, skb, r, sk_user_ns(NETLINK_CB(cb->skb).sk), NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, commp->net_admin) < 0) { err = 2; goto out; } next: cb->args[4]++; out: return err; } /* define the functions for sctp_diag_handler*/ static void sctp_diag_get_info(struct sock *sk, struct inet_diag_msg *r, void *info) { struct sctp_infox *infox = (struct sctp_infox *)info; if (infox->asoc) { r->idiag_rqueue = atomic_read(&infox->asoc->rmem_alloc); r->idiag_wqueue = infox->asoc->sndbuf_used; } else { r->idiag_rqueue = sk->sk_ack_backlog; r->idiag_wqueue = sk->sk_max_ack_backlog; } if (infox->sctpinfo) sctp_get_sctp_info(sk, infox->asoc, infox->sctpinfo); } static int sctp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh, const struct inet_diag_req_v2 *req) { struct net *net = sock_net(in_skb->sk); union sctp_addr laddr, paddr; struct sctp_comm_param commp = { .skb = in_skb, .r = req, .nlh = nlh, .net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN), }; if (req->sdiag_family == AF_INET) { laddr.v4.sin_port = req->id.idiag_sport; laddr.v4.sin_addr.s_addr = req->id.idiag_src[0]; laddr.v4.sin_family = AF_INET; paddr.v4.sin_port = req->id.idiag_dport; paddr.v4.sin_addr.s_addr = req->id.idiag_dst[0]; paddr.v4.sin_family = AF_INET; } else { laddr.v6.sin6_port = req->id.idiag_sport; memcpy(&laddr.v6.sin6_addr, req->id.idiag_src, sizeof(laddr.v6.sin6_addr)); laddr.v6.sin6_family = AF_INET6; paddr.v6.sin6_port = req->id.idiag_dport; memcpy(&paddr.v6.sin6_addr, req->id.idiag_dst, sizeof(paddr.v6.sin6_addr)); paddr.v6.sin6_family = AF_INET6; } return sctp_transport_lookup_process(sctp_tsp_dump_one, net, &laddr, &paddr, &commp); } static void sctp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, const struct inet_diag_req_v2 *r, struct nlattr *bc) { u32 idiag_states = r->idiag_states; struct net *net = sock_net(skb->sk); struct sctp_comm_param commp = { .skb = skb, .cb = cb, .r = r, .net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN), }; int pos = cb->args[2]; /* eps hashtable dumps * args: * 0 : if it will traversal listen sock * 1 : to record the sock pos of this time's traversal * 4 : to work as a temporary variable to traversal list */ if (cb->args[0] == 0) { if (!(idiag_states & TCPF_LISTEN)) goto skip; if (sctp_for_each_endpoint(sctp_ep_dump, &commp)) goto done; skip: cb->args[0] = 1; cb->args[1] = 0; cb->args[4] = 0; } /* asocs by transport hashtable dump * args: * 1 : to record the assoc pos of this time's traversal * 2 : to record the transport pos of this time's traversal * 3 : to mark if we have dumped the ep info of the current asoc * 4 : to work as a temporary variable to traversal list * 5 : to save the sk we get from travelsing the tsp list. */ if (!(idiag_states & ~(TCPF_LISTEN | TCPF_CLOSE))) goto done; sctp_for_each_transport(sctp_sock_filter, sctp_sock_dump, net, &pos, &commp); cb->args[2] = pos; done: cb->args[1] = cb->args[4]; cb->args[4] = 0; } static const struct inet_diag_handler sctp_diag_handler = { .dump = sctp_diag_dump, .dump_one = sctp_diag_dump_one, .idiag_get_info = sctp_diag_get_info, .idiag_type = IPPROTO_SCTP, .idiag_info_size = sizeof(struct sctp_info), }; static int __init sctp_diag_init(void) { return inet_diag_register(&sctp_diag_handler); } static void __exit sctp_diag_exit(void) { inet_diag_unregister(&sctp_diag_handler); } module_init(sctp_diag_init); module_exit(sctp_diag_exit); MODULE_LICENSE("GPL"); MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-132);