// SPDX-License-Identifier: GPL-2.0 /* Multipath TCP * * Copyright (c) 2022, Intel Corporation. */ #include "protocol.h" #include "mib.h" #include "mptcp_pm_gen.h" void mptcp_free_local_addr_list(struct mptcp_sock *msk) { struct mptcp_pm_addr_entry *entry, *tmp; struct sock *sk = (struct sock *)msk; LIST_HEAD(free_list); if (!mptcp_pm_is_userspace(msk)) return; spin_lock_bh(&msk->pm.lock); list_splice_init(&msk->pm.userspace_pm_local_addr_list, &free_list); spin_unlock_bh(&msk->pm.lock); list_for_each_entry_safe(entry, tmp, &free_list, list) { sock_kfree_s(sk, entry, sizeof(*entry)); } } static int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk, struct mptcp_pm_addr_entry *entry, bool needs_id) { DECLARE_BITMAP(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); struct mptcp_pm_addr_entry *match = NULL; struct sock *sk = (struct sock *)msk; struct mptcp_pm_addr_entry *e; bool addr_match = false; bool id_match = false; int ret = -EINVAL; bitmap_zero(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1); spin_lock_bh(&msk->pm.lock); list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) { addr_match = mptcp_addresses_equal(&e->addr, &entry->addr, true); if (addr_match && entry->addr.id == 0 && needs_id) entry->addr.id = e->addr.id; id_match = (e->addr.id == entry->addr.id); if (addr_match && id_match) { match = e; break; } else if (addr_match || id_match) { break; } __set_bit(e->addr.id, id_bitmap); } if (!match && !addr_match && !id_match) { /* Memory for the entry is allocated from the * sock option buffer. */ e = sock_kmalloc(sk, sizeof(*e), GFP_ATOMIC); if (!e) { ret = -ENOMEM; goto append_err; } *e = *entry; if (!e->addr.id && needs_id) e->addr.id = find_next_zero_bit(id_bitmap, MPTCP_PM_MAX_ADDR_ID + 1, 1); list_add_tail_rcu(&e->list, &msk->pm.userspace_pm_local_addr_list); msk->pm.local_addr_used++; ret = e->addr.id; } else if (match) { ret = entry->addr.id; } append_err: spin_unlock_bh(&msk->pm.lock); return ret; } /* If the subflow is closed from the other peer (not via a * subflow destroy command then), we want to keep the entry * not to assign the same ID to another address and to be * able to send RM_ADDR after the removal of the subflow. */ static int mptcp_userspace_pm_delete_local_addr(struct mptcp_sock *msk, struct mptcp_pm_addr_entry *addr) { struct mptcp_pm_addr_entry *entry, *tmp; list_for_each_entry_safe(entry, tmp, &msk->pm.userspace_pm_local_addr_list, list) { if (mptcp_addresses_equal(&entry->addr, &addr->addr, false)) { /* TODO: a refcount is needed because the entry can * be used multiple times (e.g. fullmesh mode). */ list_del_rcu(&entry->list); kfree(entry); msk->pm.local_addr_used--; return 0; } } return -EINVAL; } static struct mptcp_pm_addr_entry * mptcp_userspace_pm_lookup_addr_by_id(struct mptcp_sock *msk, unsigned int id) { struct mptcp_pm_addr_entry *entry; list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { if (entry->addr.id == id) return entry; } return NULL; } int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id, u8 *flags, int *ifindex) { struct mptcp_pm_addr_entry *match; spin_lock_bh(&msk->pm.lock); match = mptcp_userspace_pm_lookup_addr_by_id(msk, id); spin_unlock_bh(&msk->pm.lock); if (match) { *flags = match->flags; *ifindex = match->ifindex; } return 0; } int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc) { struct mptcp_pm_addr_entry *entry = NULL, *e, new_entry; __be16 msk_sport = ((struct inet_sock *) inet_sk((struct sock *)msk))->inet_sport; spin_lock_bh(&msk->pm.lock); list_for_each_entry(e, &msk->pm.userspace_pm_local_addr_list, list) { if (mptcp_addresses_equal(&e->addr, skc, false)) { entry = e; break; } } spin_unlock_bh(&msk->pm.lock); if (entry) return entry->addr.id; memset(&new_entry, 0, sizeof(struct mptcp_pm_addr_entry)); new_entry.addr = *skc; new_entry.addr.id = 0; new_entry.flags = MPTCP_PM_ADDR_FLAG_IMPLICIT; if (new_entry.addr.port == msk_sport) new_entry.addr.port = 0; return mptcp_userspace_pm_append_new_local_addr(msk, &new_entry, true); } bool mptcp_userspace_pm_is_backup(struct mptcp_sock *msk, struct mptcp_addr_info *skc) { struct mptcp_pm_addr_entry *entry; bool backup = false; spin_lock_bh(&msk->pm.lock); list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { if (mptcp_addresses_equal(&entry->addr, skc, false)) { backup = !!(entry->flags & MPTCP_PM_ADDR_FLAG_BACKUP); break; } } spin_unlock_bh(&msk->pm.lock); return backup; } int mptcp_pm_nl_announce_doit(struct sk_buff *skb, struct genl_info *info) { struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; struct nlattr *addr = info->attrs[MPTCP_PM_ATTR_ADDR]; struct mptcp_pm_addr_entry addr_val; struct mptcp_sock *msk; int err = -EINVAL; struct sock *sk; u32 token_val; if (!addr || !token) { GENL_SET_ERR_MSG(info, "missing required inputs"); return err; } token_val = nla_get_u32(token); msk = mptcp_token_get_sock(sock_net(skb->sk), token_val); if (!msk) { NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); return err; } sk = (struct sock *)msk; if (!mptcp_pm_is_userspace(msk)) { GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); goto announce_err; } err = mptcp_pm_parse_entry(addr, info, true, &addr_val); if (err < 0) { GENL_SET_ERR_MSG(info, "error parsing local address"); goto announce_err; } if (addr_val.addr.id == 0 || !(addr_val.flags & MPTCP_PM_ADDR_FLAG_SIGNAL)) { GENL_SET_ERR_MSG(info, "invalid addr id or flags"); err = -EINVAL; goto announce_err; } err = mptcp_userspace_pm_append_new_local_addr(msk, &addr_val, false); if (err < 0) { GENL_SET_ERR_MSG(info, "did not match address and id"); goto announce_err; } lock_sock(sk); spin_lock_bh(&msk->pm.lock); if (mptcp_pm_alloc_anno_list(msk, &addr_val.addr)) { msk->pm.add_addr_signaled++; mptcp_pm_announce_addr(msk, &addr_val.addr, false); mptcp_pm_nl_addr_send_ack(msk); } spin_unlock_bh(&msk->pm.lock); release_sock(sk); err = 0; announce_err: sock_put(sk); return err; } static int mptcp_userspace_pm_remove_id_zero_address(struct mptcp_sock *msk, struct genl_info *info) { struct mptcp_rm_list list = { .nr = 0 }; struct mptcp_subflow_context *subflow; struct sock *sk = (struct sock *)msk; bool has_id_0 = false; int err = -EINVAL; lock_sock(sk); mptcp_for_each_subflow(msk, subflow) { if (READ_ONCE(subflow->local_id) == 0) { has_id_0 = true; break; } } if (!has_id_0) { GENL_SET_ERR_MSG(info, "address with id 0 not found"); goto remove_err; } list.ids[list.nr++] = 0; spin_lock_bh(&msk->pm.lock); mptcp_pm_remove_addr(msk, &list); spin_unlock_bh(&msk->pm.lock); err = 0; remove_err: release_sock(sk); return err; } int mptcp_pm_nl_remove_doit(struct sk_buff *skb, struct genl_info *info) { struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; struct nlattr *id = info->attrs[MPTCP_PM_ATTR_LOC_ID]; struct mptcp_pm_addr_entry *match; struct mptcp_pm_addr_entry *entry; struct mptcp_sock *msk; LIST_HEAD(free_list); int err = -EINVAL; struct sock *sk; u32 token_val; u8 id_val; if (!id || !token) { GENL_SET_ERR_MSG(info, "missing required inputs"); return err; } id_val = nla_get_u8(id); token_val = nla_get_u32(token); msk = mptcp_token_get_sock(sock_net(skb->sk), token_val); if (!msk) { NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); return err; } sk = (struct sock *)msk; if (!mptcp_pm_is_userspace(msk)) { GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); goto out; } if (id_val == 0) { err = mptcp_userspace_pm_remove_id_zero_address(msk, info); goto out; } lock_sock(sk); match = mptcp_userspace_pm_lookup_addr_by_id(msk, id_val); if (!match) { GENL_SET_ERR_MSG(info, "address with specified id not found"); release_sock(sk); goto out; } list_move(&match->list, &free_list); mptcp_pm_remove_addrs(msk, &free_list); release_sock(sk); list_for_each_entry_safe(match, entry, &free_list, list) { sock_kfree_s(sk, match, sizeof(*match)); } err = 0; out: sock_put(sk); return err; } int mptcp_pm_nl_subflow_create_doit(struct sk_buff *skb, struct genl_info *info) { struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR]; struct mptcp_pm_addr_entry local = { 0 }; struct mptcp_addr_info addr_r; struct mptcp_sock *msk; int err = -EINVAL; struct sock *sk; u32 token_val; if (!laddr || !raddr || !token) { GENL_SET_ERR_MSG(info, "missing required inputs"); return err; } token_val = nla_get_u32(token); msk = mptcp_token_get_sock(genl_info_net(info), token_val); if (!msk) { NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); return err; } sk = (struct sock *)msk; if (!mptcp_pm_is_userspace(msk)) { GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); goto create_err; } err = mptcp_pm_parse_entry(laddr, info, true, &local); if (err < 0) { NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr"); goto create_err; } if (local.flags & MPTCP_PM_ADDR_FLAG_SIGNAL) { GENL_SET_ERR_MSG(info, "invalid addr flags"); err = -EINVAL; goto create_err; } local.flags |= MPTCP_PM_ADDR_FLAG_SUBFLOW; err = mptcp_pm_parse_addr(raddr, info, &addr_r); if (err < 0) { NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr"); goto create_err; } if (!mptcp_pm_addr_families_match(sk, &local.addr, &addr_r)) { GENL_SET_ERR_MSG(info, "families mismatch"); err = -EINVAL; goto create_err; } err = mptcp_userspace_pm_append_new_local_addr(msk, &local, false); if (err < 0) { GENL_SET_ERR_MSG(info, "did not match address and id"); goto create_err; } lock_sock(sk); err = __mptcp_subflow_connect(sk, &local.addr, &addr_r); release_sock(sk); spin_lock_bh(&msk->pm.lock); if (err) mptcp_userspace_pm_delete_local_addr(msk, &local); else msk->pm.subflows++; spin_unlock_bh(&msk->pm.lock); create_err: sock_put(sk); return err; } static struct sock *mptcp_nl_find_ssk(struct mptcp_sock *msk, const struct mptcp_addr_info *local, const struct mptcp_addr_info *remote) { struct mptcp_subflow_context *subflow; if (local->family != remote->family) return NULL; mptcp_for_each_subflow(msk, subflow) { const struct inet_sock *issk; struct sock *ssk; ssk = mptcp_subflow_tcp_sock(subflow); if (local->family != ssk->sk_family) continue; issk = inet_sk(ssk); switch (ssk->sk_family) { case AF_INET: if (issk->inet_saddr != local->addr.s_addr || issk->inet_daddr != remote->addr.s_addr) continue; break; #if IS_ENABLED(CONFIG_MPTCP_IPV6) case AF_INET6: { const struct ipv6_pinfo *pinfo = inet6_sk(ssk); if (!ipv6_addr_equal(&local->addr6, &pinfo->saddr) || !ipv6_addr_equal(&remote->addr6, &ssk->sk_v6_daddr)) continue; break; } #endif default: continue; } if (issk->inet_sport == local->port && issk->inet_dport == remote->port) return ssk; } return NULL; } int mptcp_pm_nl_subflow_destroy_doit(struct sk_buff *skb, struct genl_info *info) { struct nlattr *raddr = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; struct nlattr *laddr = info->attrs[MPTCP_PM_ATTR_ADDR]; struct mptcp_addr_info addr_l; struct mptcp_addr_info addr_r; struct mptcp_sock *msk; struct sock *sk, *ssk; int err = -EINVAL; u32 token_val; if (!laddr || !raddr || !token) { GENL_SET_ERR_MSG(info, "missing required inputs"); return err; } token_val = nla_get_u32(token); msk = mptcp_token_get_sock(genl_info_net(info), token_val); if (!msk) { NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); return err; } sk = (struct sock *)msk; if (!mptcp_pm_is_userspace(msk)) { GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); goto destroy_err; } err = mptcp_pm_parse_addr(laddr, info, &addr_l); if (err < 0) { NL_SET_ERR_MSG_ATTR(info->extack, laddr, "error parsing local addr"); goto destroy_err; } err = mptcp_pm_parse_addr(raddr, info, &addr_r); if (err < 0) { NL_SET_ERR_MSG_ATTR(info->extack, raddr, "error parsing remote addr"); goto destroy_err; } #if IS_ENABLED(CONFIG_MPTCP_IPV6) if (addr_l.family == AF_INET && ipv6_addr_v4mapped(&addr_r.addr6)) { ipv6_addr_set_v4mapped(addr_l.addr.s_addr, &addr_l.addr6); addr_l.family = AF_INET6; } if (addr_r.family == AF_INET && ipv6_addr_v4mapped(&addr_l.addr6)) { ipv6_addr_set_v4mapped(addr_r.addr.s_addr, &addr_r.addr6); addr_r.family = AF_INET6; } #endif if (addr_l.family != addr_r.family) { GENL_SET_ERR_MSG(info, "address families do not match"); err = -EINVAL; goto destroy_err; } if (!addr_l.port || !addr_r.port) { GENL_SET_ERR_MSG(info, "missing local or remote port"); err = -EINVAL; goto destroy_err; } lock_sock(sk); ssk = mptcp_nl_find_ssk(msk, &addr_l, &addr_r); if (ssk) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); struct mptcp_pm_addr_entry entry = { .addr = addr_l }; spin_lock_bh(&msk->pm.lock); mptcp_userspace_pm_delete_local_addr(msk, &entry); spin_unlock_bh(&msk->pm.lock); mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN); mptcp_close_ssk(sk, ssk, subflow); MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW); err = 0; } else { err = -ESRCH; } release_sock(sk); destroy_err: sock_put(sk); return err; } int mptcp_userspace_pm_set_flags(struct sk_buff *skb, struct genl_info *info) { struct mptcp_pm_addr_entry loc = { .addr = { .family = AF_UNSPEC }, }; struct mptcp_pm_addr_entry rem = { .addr = { .family = AF_UNSPEC }, }; struct nlattr *attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE]; struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR]; struct net *net = sock_net(skb->sk); struct mptcp_sock *msk; int ret = -EINVAL; struct sock *sk; u32 token_val; u8 bkup = 0; token_val = nla_get_u32(token); msk = mptcp_token_get_sock(net, token_val); if (!msk) { NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); return ret; } sk = (struct sock *)msk; if (!mptcp_pm_is_userspace(msk)) { GENL_SET_ERR_MSG(info, "userspace PM not selected"); goto set_flags_err; } ret = mptcp_pm_parse_entry(attr, info, false, &loc); if (ret < 0) goto set_flags_err; if (attr_rem) { ret = mptcp_pm_parse_entry(attr_rem, info, false, &rem); if (ret < 0) goto set_flags_err; } if (loc.addr.family == AF_UNSPEC || rem.addr.family == AF_UNSPEC) { GENL_SET_ERR_MSG(info, "invalid address families"); ret = -EINVAL; goto set_flags_err; } if (loc.flags & MPTCP_PM_ADDR_FLAG_BACKUP) bkup = 1; lock_sock(sk); ret = mptcp_pm_nl_mp_prio_send_ack(msk, &loc.addr, &rem.addr, bkup); release_sock(sk); set_flags_err: sock_put(sk); return ret; } int mptcp_userspace_pm_dump_addr(struct sk_buff *msg, struct netlink_callback *cb) { struct id_bitmap { DECLARE_BITMAP(map, MPTCP_PM_MAX_ADDR_ID + 1); } *bitmap; const struct genl_info *info = genl_info_dump(cb); struct net *net = sock_net(msg->sk); struct mptcp_pm_addr_entry *entry; struct mptcp_sock *msk; struct nlattr *token; int ret = -EINVAL; struct sock *sk; void *hdr; bitmap = (struct id_bitmap *)cb->ctx; token = info->attrs[MPTCP_PM_ATTR_TOKEN]; msk = mptcp_token_get_sock(net, nla_get_u32(token)); if (!msk) { NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); return ret; } sk = (struct sock *)msk; if (!mptcp_pm_is_userspace(msk)) { GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); goto out; } lock_sock(sk); spin_lock_bh(&msk->pm.lock); list_for_each_entry(entry, &msk->pm.userspace_pm_local_addr_list, list) { if (test_bit(entry->addr.id, bitmap->map)) continue; hdr = genlmsg_put(msg, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, &mptcp_genl_family, NLM_F_MULTI, MPTCP_PM_CMD_GET_ADDR); if (!hdr) break; if (mptcp_nl_fill_addr(msg, entry) < 0) { genlmsg_cancel(msg, hdr); break; } __set_bit(entry->addr.id, bitmap->map); genlmsg_end(msg, hdr); } spin_unlock_bh(&msk->pm.lock); release_sock(sk); ret = msg->len; out: sock_put(sk); return ret; } int mptcp_userspace_pm_get_addr(struct sk_buff *skb, struct genl_info *info) { struct nlattr *attr = info->attrs[MPTCP_PM_ENDPOINT_ADDR]; struct nlattr *token = info->attrs[MPTCP_PM_ATTR_TOKEN]; struct mptcp_pm_addr_entry addr, *entry; struct net *net = sock_net(skb->sk); struct mptcp_sock *msk; struct sk_buff *msg; int ret = -EINVAL; struct sock *sk; void *reply; msk = mptcp_token_get_sock(net, nla_get_u32(token)); if (!msk) { NL_SET_ERR_MSG_ATTR(info->extack, token, "invalid token"); return ret; } sk = (struct sock *)msk; if (!mptcp_pm_is_userspace(msk)) { GENL_SET_ERR_MSG(info, "invalid request; userspace PM not selected"); goto out; } ret = mptcp_pm_parse_entry(attr, info, false, &addr); if (ret < 0) goto out; msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); if (!msg) { ret = -ENOMEM; goto out; } reply = genlmsg_put_reply(msg, info, &mptcp_genl_family, 0, info->genlhdr->cmd); if (!reply) { GENL_SET_ERR_MSG(info, "not enough space in Netlink message"); ret = -EMSGSIZE; goto fail; } lock_sock(sk); spin_lock_bh(&msk->pm.lock); entry = mptcp_userspace_pm_lookup_addr_by_id(msk, addr.addr.id); if (!entry) { GENL_SET_ERR_MSG(info, "address not found"); ret = -EINVAL; goto unlock_fail; } ret = mptcp_nl_fill_addr(msg, entry); if (ret) goto unlock_fail; genlmsg_end(msg, reply); ret = genlmsg_reply(msg, info); spin_unlock_bh(&msk->pm.lock); release_sock(sk); sock_put(sk); return ret; unlock_fail: spin_unlock_bh(&msk->pm.lock); release_sock(sk); fail: nlmsg_free(msg); out: sock_put(sk); return ret; }