/net/mctp/af_mctp.c
C | 689 lines | 519 code | 134 blank | 36 comment | 87 complexity | 1b86ee00a2ef1143a12f3e2c862fb615 MD5 | raw file
- // SPDX-License-Identifier: GPL-2.0
- /*
- * Management Component Transport Protocol (MCTP)
- *
- * Copyright (c) 2021 Code Construct
- * Copyright (c) 2021 Google
- */
- #include <linux/compat.h>
- #include <linux/if_arp.h>
- #include <linux/net.h>
- #include <linux/mctp.h>
- #include <linux/module.h>
- #include <linux/socket.h>
- #include <net/mctp.h>
- #include <net/mctpdevice.h>
- #include <net/sock.h>
- #define CREATE_TRACE_POINTS
- #include <trace/events/mctp.h>
- /* socket implementation */
- static void mctp_sk_expire_keys(struct timer_list *timer);
- static int mctp_release(struct socket *sock)
- {
- struct sock *sk = sock->sk;
- if (sk) {
- sock->sk = NULL;
- sk->sk_prot->close(sk, 0);
- }
- return 0;
- }
- /* Generic sockaddr checks, padding checks only so far */
- static bool mctp_sockaddr_is_ok(const struct sockaddr_mctp *addr)
- {
- return !addr->__smctp_pad0 && !addr->__smctp_pad1;
- }
- static bool mctp_sockaddr_ext_is_ok(const struct sockaddr_mctp_ext *addr)
- {
- return !addr->__smctp_pad0[0] &&
- !addr->__smctp_pad0[1] &&
- !addr->__smctp_pad0[2];
- }
- static int mctp_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
- {
- struct sock *sk = sock->sk;
- struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
- struct sockaddr_mctp *smctp;
- int rc;
- if (addrlen < sizeof(*smctp))
- return -EINVAL;
- if (addr->sa_family != AF_MCTP)
- return -EAFNOSUPPORT;
- if (!capable(CAP_NET_BIND_SERVICE))
- return -EACCES;
- /* it's a valid sockaddr for MCTP, cast and do protocol checks */
- smctp = (struct sockaddr_mctp *)addr;
- if (!mctp_sockaddr_is_ok(smctp))
- return -EINVAL;
- lock_sock(sk);
- /* TODO: allow rebind */
- if (sk_hashed(sk)) {
- rc = -EADDRINUSE;
- goto out_release;
- }
- msk->bind_net = smctp->smctp_network;
- msk->bind_addr = smctp->smctp_addr.s_addr;
- msk->bind_type = smctp->smctp_type & 0x7f; /* ignore the IC bit */
- rc = sk->sk_prot->hash(sk);
- out_release:
- release_sock(sk);
- return rc;
- }
- static int mctp_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
- {
- DECLARE_SOCKADDR(struct sockaddr_mctp *, addr, msg->msg_name);
- int rc, addrlen = msg->msg_namelen;
- struct sock *sk = sock->sk;
- struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
- struct mctp_skb_cb *cb;
- struct mctp_route *rt;
- struct sk_buff *skb = NULL;
- int hlen;
- if (addr) {
- const u8 tagbits = MCTP_TAG_MASK | MCTP_TAG_OWNER |
- MCTP_TAG_PREALLOC;
- if (addrlen < sizeof(struct sockaddr_mctp))
- return -EINVAL;
- if (addr->smctp_family != AF_MCTP)
- return -EINVAL;
- if (!mctp_sockaddr_is_ok(addr))
- return -EINVAL;
- if (addr->smctp_tag & ~tagbits)
- return -EINVAL;
- /* can't preallocate a non-owned tag */
- if (addr->smctp_tag & MCTP_TAG_PREALLOC &&
- !(addr->smctp_tag & MCTP_TAG_OWNER))
- return -EINVAL;
- } else {
- /* TODO: connect()ed sockets */
- return -EDESTADDRREQ;
- }
- if (!capable(CAP_NET_RAW))
- return -EACCES;
- if (addr->smctp_network == MCTP_NET_ANY)
- addr->smctp_network = mctp_default_net(sock_net(sk));
- /* direct addressing */
- if (msk->addr_ext && addrlen >= sizeof(struct sockaddr_mctp_ext)) {
- DECLARE_SOCKADDR(struct sockaddr_mctp_ext *,
- extaddr, msg->msg_name);
- struct net_device *dev;
- rc = -EINVAL;
- rcu_read_lock();
- dev = dev_get_by_index_rcu(sock_net(sk), extaddr->smctp_ifindex);
- /* check for correct halen */
- if (dev && extaddr->smctp_halen == dev->addr_len) {
- hlen = LL_RESERVED_SPACE(dev) + sizeof(struct mctp_hdr);
- rc = 0;
- }
- rcu_read_unlock();
- if (rc)
- goto err_free;
- rt = NULL;
- } else {
- rt = mctp_route_lookup(sock_net(sk), addr->smctp_network,
- addr->smctp_addr.s_addr);
- if (!rt) {
- rc = -EHOSTUNREACH;
- goto err_free;
- }
- hlen = LL_RESERVED_SPACE(rt->dev->dev) + sizeof(struct mctp_hdr);
- }
- skb = sock_alloc_send_skb(sk, hlen + 1 + len,
- msg->msg_flags & MSG_DONTWAIT, &rc);
- if (!skb)
- return rc;
- skb_reserve(skb, hlen);
- /* set type as fist byte in payload */
- *(u8 *)skb_put(skb, 1) = addr->smctp_type;
- rc = memcpy_from_msg((void *)skb_put(skb, len), msg, len);
- if (rc < 0)
- goto err_free;
- /* set up cb */
- cb = __mctp_cb(skb);
- cb->net = addr->smctp_network;
- if (!rt) {
- /* fill extended address in cb */
- DECLARE_SOCKADDR(struct sockaddr_mctp_ext *,
- extaddr, msg->msg_name);
- if (!mctp_sockaddr_ext_is_ok(extaddr) ||
- extaddr->smctp_halen > sizeof(cb->haddr)) {
- rc = -EINVAL;
- goto err_free;
- }
- cb->ifindex = extaddr->smctp_ifindex;
- /* smctp_halen is checked above */
- cb->halen = extaddr->smctp_halen;
- memcpy(cb->haddr, extaddr->smctp_haddr, cb->halen);
- }
- rc = mctp_local_output(sk, rt, skb, addr->smctp_addr.s_addr,
- addr->smctp_tag);
- return rc ? : len;
- err_free:
- kfree_skb(skb);
- return rc;
- }
- static int mctp_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
- int flags)
- {
- DECLARE_SOCKADDR(struct sockaddr_mctp *, addr, msg->msg_name);
- struct sock *sk = sock->sk;
- struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
- struct sk_buff *skb;
- size_t msglen;
- u8 type;
- int rc;
- if (flags & ~(MSG_DONTWAIT | MSG_TRUNC | MSG_PEEK))
- return -EOPNOTSUPP;
- skb = skb_recv_datagram(sk, flags, &rc);
- if (!skb)
- return rc;
- if (!skb->len) {
- rc = 0;
- goto out_free;
- }
- /* extract message type, remove from data */
- type = *((u8 *)skb->data);
- msglen = skb->len - 1;
- if (len < msglen)
- msg->msg_flags |= MSG_TRUNC;
- else
- len = msglen;
- rc = skb_copy_datagram_msg(skb, 1, msg, len);
- if (rc < 0)
- goto out_free;
- sock_recv_cmsgs(msg, sk, skb);
- if (addr) {
- struct mctp_skb_cb *cb = mctp_cb(skb);
- /* TODO: expand mctp_skb_cb for header fields? */
- struct mctp_hdr *hdr = mctp_hdr(skb);
- addr = msg->msg_name;
- addr->smctp_family = AF_MCTP;
- addr->__smctp_pad0 = 0;
- addr->smctp_network = cb->net;
- addr->smctp_addr.s_addr = hdr->src;
- addr->smctp_type = type;
- addr->smctp_tag = hdr->flags_seq_tag &
- (MCTP_HDR_TAG_MASK | MCTP_HDR_FLAG_TO);
- addr->__smctp_pad1 = 0;
- msg->msg_namelen = sizeof(*addr);
- if (msk->addr_ext) {
- DECLARE_SOCKADDR(struct sockaddr_mctp_ext *, ae,
- msg->msg_name);
- msg->msg_namelen = sizeof(*ae);
- ae->smctp_ifindex = cb->ifindex;
- ae->smctp_halen = cb->halen;
- memset(ae->__smctp_pad0, 0x0, sizeof(ae->__smctp_pad0));
- memset(ae->smctp_haddr, 0x0, sizeof(ae->smctp_haddr));
- memcpy(ae->smctp_haddr, cb->haddr, cb->halen);
- }
- }
- rc = len;
- if (flags & MSG_TRUNC)
- rc = msglen;
- out_free:
- skb_free_datagram(sk, skb);
- return rc;
- }
- /* We're done with the key; invalidate, stop reassembly, and remove from lists.
- */
- static void __mctp_key_remove(struct mctp_sk_key *key, struct net *net,
- unsigned long flags, unsigned long reason)
- __releases(&key->lock)
- __must_hold(&net->mctp.keys_lock)
- {
- struct sk_buff *skb;
- trace_mctp_key_release(key, reason);
- skb = key->reasm_head;
- key->reasm_head = NULL;
- key->reasm_dead = true;
- key->valid = false;
- mctp_dev_release_key(key->dev, key);
- spin_unlock_irqrestore(&key->lock, flags);
- hlist_del(&key->hlist);
- hlist_del(&key->sklist);
- /* unref for the lists */
- mctp_key_unref(key);
- kfree_skb(skb);
- }
- static int mctp_setsockopt(struct socket *sock, int level, int optname,
- sockptr_t optval, unsigned int optlen)
- {
- struct mctp_sock *msk = container_of(sock->sk, struct mctp_sock, sk);
- int val;
- if (level != SOL_MCTP)
- return -EINVAL;
- if (optname == MCTP_OPT_ADDR_EXT) {
- if (optlen != sizeof(int))
- return -EINVAL;
- if (copy_from_sockptr(&val, optval, sizeof(int)))
- return -EFAULT;
- msk->addr_ext = val;
- return 0;
- }
- return -ENOPROTOOPT;
- }
- static int mctp_getsockopt(struct socket *sock, int level, int optname,
- char __user *optval, int __user *optlen)
- {
- struct mctp_sock *msk = container_of(sock->sk, struct mctp_sock, sk);
- int len, val;
- if (level != SOL_MCTP)
- return -EINVAL;
- if (get_user(len, optlen))
- return -EFAULT;
- if (optname == MCTP_OPT_ADDR_EXT) {
- if (len != sizeof(int))
- return -EINVAL;
- val = !!msk->addr_ext;
- if (copy_to_user(optval, &val, len))
- return -EFAULT;
- return 0;
- }
- return -EINVAL;
- }
- static int mctp_ioctl_alloctag(struct mctp_sock *msk, unsigned long arg)
- {
- struct net *net = sock_net(&msk->sk);
- struct mctp_sk_key *key = NULL;
- struct mctp_ioc_tag_ctl ctl;
- unsigned long flags;
- u8 tag;
- if (copy_from_user(&ctl, (void __user *)arg, sizeof(ctl)))
- return -EFAULT;
- if (ctl.tag)
- return -EINVAL;
- if (ctl.flags)
- return -EINVAL;
- key = mctp_alloc_local_tag(msk, ctl.peer_addr, MCTP_ADDR_ANY,
- true, &tag);
- if (IS_ERR(key))
- return PTR_ERR(key);
- ctl.tag = tag | MCTP_TAG_OWNER | MCTP_TAG_PREALLOC;
- if (copy_to_user((void __user *)arg, &ctl, sizeof(ctl))) {
- spin_lock_irqsave(&key->lock, flags);
- __mctp_key_remove(key, net, flags, MCTP_TRACE_KEY_DROPPED);
- mctp_key_unref(key);
- return -EFAULT;
- }
- mctp_key_unref(key);
- return 0;
- }
- static int mctp_ioctl_droptag(struct mctp_sock *msk, unsigned long arg)
- {
- struct net *net = sock_net(&msk->sk);
- struct mctp_ioc_tag_ctl ctl;
- unsigned long flags, fl2;
- struct mctp_sk_key *key;
- struct hlist_node *tmp;
- int rc;
- u8 tag;
- if (copy_from_user(&ctl, (void __user *)arg, sizeof(ctl)))
- return -EFAULT;
- if (ctl.flags)
- return -EINVAL;
- /* Must be a local tag, TO set, preallocated */
- if ((ctl.tag & ~MCTP_TAG_MASK) != (MCTP_TAG_OWNER | MCTP_TAG_PREALLOC))
- return -EINVAL;
- tag = ctl.tag & MCTP_TAG_MASK;
- rc = -EINVAL;
- spin_lock_irqsave(&net->mctp.keys_lock, flags);
- hlist_for_each_entry_safe(key, tmp, &msk->keys, sklist) {
- /* we do an irqsave here, even though we know the irq state,
- * so we have the flags to pass to __mctp_key_remove
- */
- spin_lock_irqsave(&key->lock, fl2);
- if (key->manual_alloc &&
- ctl.peer_addr == key->peer_addr &&
- tag == key->tag) {
- __mctp_key_remove(key, net, fl2,
- MCTP_TRACE_KEY_DROPPED);
- rc = 0;
- } else {
- spin_unlock_irqrestore(&key->lock, fl2);
- }
- }
- spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
- return rc;
- }
- static int mctp_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
- {
- struct mctp_sock *msk = container_of(sock->sk, struct mctp_sock, sk);
- switch (cmd) {
- case SIOCMCTPALLOCTAG:
- return mctp_ioctl_alloctag(msk, arg);
- case SIOCMCTPDROPTAG:
- return mctp_ioctl_droptag(msk, arg);
- }
- return -EINVAL;
- }
- #ifdef CONFIG_COMPAT
- static int mctp_compat_ioctl(struct socket *sock, unsigned int cmd,
- unsigned long arg)
- {
- void __user *argp = compat_ptr(arg);
- switch (cmd) {
- /* These have compatible ptr layouts */
- case SIOCMCTPALLOCTAG:
- case SIOCMCTPDROPTAG:
- return mctp_ioctl(sock, cmd, (unsigned long)argp);
- }
- return -ENOIOCTLCMD;
- }
- #endif
- static const struct proto_ops mctp_dgram_ops = {
- .family = PF_MCTP,
- .release = mctp_release,
- .bind = mctp_bind,
- .connect = sock_no_connect,
- .socketpair = sock_no_socketpair,
- .accept = sock_no_accept,
- .getname = sock_no_getname,
- .poll = datagram_poll,
- .ioctl = mctp_ioctl,
- .gettstamp = sock_gettstamp,
- .listen = sock_no_listen,
- .shutdown = sock_no_shutdown,
- .setsockopt = mctp_setsockopt,
- .getsockopt = mctp_getsockopt,
- .sendmsg = mctp_sendmsg,
- .recvmsg = mctp_recvmsg,
- .mmap = sock_no_mmap,
- .sendpage = sock_no_sendpage,
- #ifdef CONFIG_COMPAT
- .compat_ioctl = mctp_compat_ioctl,
- #endif
- };
- static void mctp_sk_expire_keys(struct timer_list *timer)
- {
- struct mctp_sock *msk = container_of(timer, struct mctp_sock,
- key_expiry);
- struct net *net = sock_net(&msk->sk);
- unsigned long next_expiry, flags, fl2;
- struct mctp_sk_key *key;
- struct hlist_node *tmp;
- bool next_expiry_valid = false;
- spin_lock_irqsave(&net->mctp.keys_lock, flags);
- hlist_for_each_entry_safe(key, tmp, &msk->keys, sklist) {
- /* don't expire. manual_alloc is immutable, no locking
- * required.
- */
- if (key->manual_alloc)
- continue;
- spin_lock_irqsave(&key->lock, fl2);
- if (!time_after_eq(key->expiry, jiffies)) {
- __mctp_key_remove(key, net, fl2,
- MCTP_TRACE_KEY_TIMEOUT);
- continue;
- }
- if (next_expiry_valid) {
- if (time_before(key->expiry, next_expiry))
- next_expiry = key->expiry;
- } else {
- next_expiry = key->expiry;
- next_expiry_valid = true;
- }
- spin_unlock_irqrestore(&key->lock, fl2);
- }
- spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
- if (next_expiry_valid)
- mod_timer(timer, next_expiry);
- }
- static int mctp_sk_init(struct sock *sk)
- {
- struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
- INIT_HLIST_HEAD(&msk->keys);
- timer_setup(&msk->key_expiry, mctp_sk_expire_keys, 0);
- return 0;
- }
- static void mctp_sk_close(struct sock *sk, long timeout)
- {
- struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
- del_timer_sync(&msk->key_expiry);
- sk_common_release(sk);
- }
- static int mctp_sk_hash(struct sock *sk)
- {
- struct net *net = sock_net(sk);
- mutex_lock(&net->mctp.bind_lock);
- sk_add_node_rcu(sk, &net->mctp.binds);
- mutex_unlock(&net->mctp.bind_lock);
- return 0;
- }
- static void mctp_sk_unhash(struct sock *sk)
- {
- struct mctp_sock *msk = container_of(sk, struct mctp_sock, sk);
- struct net *net = sock_net(sk);
- unsigned long flags, fl2;
- struct mctp_sk_key *key;
- struct hlist_node *tmp;
- /* remove from any type-based binds */
- mutex_lock(&net->mctp.bind_lock);
- sk_del_node_init_rcu(sk);
- mutex_unlock(&net->mctp.bind_lock);
- /* remove tag allocations */
- spin_lock_irqsave(&net->mctp.keys_lock, flags);
- hlist_for_each_entry_safe(key, tmp, &msk->keys, sklist) {
- spin_lock_irqsave(&key->lock, fl2);
- __mctp_key_remove(key, net, fl2, MCTP_TRACE_KEY_CLOSED);
- }
- spin_unlock_irqrestore(&net->mctp.keys_lock, flags);
- }
- static struct proto mctp_proto = {
- .name = "MCTP",
- .owner = THIS_MODULE,
- .obj_size = sizeof(struct mctp_sock),
- .init = mctp_sk_init,
- .close = mctp_sk_close,
- .hash = mctp_sk_hash,
- .unhash = mctp_sk_unhash,
- };
- static int mctp_pf_create(struct net *net, struct socket *sock,
- int protocol, int kern)
- {
- const struct proto_ops *ops;
- struct proto *proto;
- struct sock *sk;
- int rc;
- if (protocol)
- return -EPROTONOSUPPORT;
- /* only datagram sockets are supported */
- if (sock->type != SOCK_DGRAM)
- return -ESOCKTNOSUPPORT;
- proto = &mctp_proto;
- ops = &mctp_dgram_ops;
- sock->state = SS_UNCONNECTED;
- sock->ops = ops;
- sk = sk_alloc(net, PF_MCTP, GFP_KERNEL, proto, kern);
- if (!sk)
- return -ENOMEM;
- sock_init_data(sock, sk);
- rc = 0;
- if (sk->sk_prot->init)
- rc = sk->sk_prot->init(sk);
- if (rc)
- goto err_sk_put;
- return 0;
- err_sk_put:
- sock_orphan(sk);
- sock_put(sk);
- return rc;
- }
- static struct net_proto_family mctp_pf = {
- .family = PF_MCTP,
- .create = mctp_pf_create,
- .owner = THIS_MODULE,
- };
- static __init int mctp_init(void)
- {
- int rc;
- /* ensure our uapi tag definitions match the header format */
- BUILD_BUG_ON(MCTP_TAG_OWNER != MCTP_HDR_FLAG_TO);
- BUILD_BUG_ON(MCTP_TAG_MASK != MCTP_HDR_TAG_MASK);
- pr_info("mctp: management component transport protocol core\n");
- rc = sock_register(&mctp_pf);
- if (rc)
- return rc;
- rc = proto_register(&mctp_proto, 0);
- if (rc)
- goto err_unreg_sock;
- rc = mctp_routes_init();
- if (rc)
- goto err_unreg_proto;
- rc = mctp_neigh_init();
- if (rc)
- goto err_unreg_proto;
- mctp_device_init();
- return 0;
- err_unreg_proto:
- proto_unregister(&mctp_proto);
- err_unreg_sock:
- sock_unregister(PF_MCTP);
- return rc;
- }
- static __exit void mctp_exit(void)
- {
- mctp_device_exit();
- mctp_neigh_exit();
- mctp_routes_exit();
- proto_unregister(&mctp_proto);
- sock_unregister(PF_MCTP);
- }
- subsys_initcall(mctp_init);
- module_exit(mctp_exit);
- MODULE_DESCRIPTION("MCTP core");
- MODULE_LICENSE("GPL v2");
- MODULE_AUTHOR("Jeremy Kerr <jk@codeconstruct.com.au>");
- MODULE_ALIAS_NETPROTO(PF_MCTP);