1 #include <linux/module.h>
2 #include <linux/version.h>
4 #include <net/protocol.h>
11 MODULE_DESCRIPTION("Multi-Party Transport Protocol");
12 MODULE_AUTHOR("Adrian Bondrescu/Cornel Mercan");
13 MODULE_LICENSE("GPL");
16 struct inet_sock sock;
17 /* mptp socket speciffic data */
22 static struct mptp_sock * sock_port_map[MAX_MPTP_PORT];
24 static inline struct mptp_sock * mptp_sk(struct sock * sock)
26 return (struct mptp_sock *)(sock);
29 static inline struct mptphdr * mptp_hdr(const struct sk_buff * skb)
31 return (struct mptphdr *) skb_transport_header(skb);
34 static inline uint16_t get_next_free_port(void)
37 for (i = MIN_MPTP_PORT; i < MAX_MPTP_PORT; i ++)
38 if (sock_port_map[i] == NULL)
43 static inline void mptp_unhash(uint16_t port)
45 sock_port_map[port] = NULL;
48 static inline void mptp_hash(uint16_t port, struct mptp_sock *ssh)
50 sock_port_map[port] = ssh;
53 static inline struct mptp_sock * mptp_lookup(uint16_t port)
55 return sock_port_map[port];
58 static int mptp_release(struct socket *sock)
60 struct sock *sk = sock->sk;
61 struct mptp_sock * ssk = mptp_sk(sk);
66 mptp_unhash(ssk->src);
68 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
75 skb_queue_purge(&sk->sk_receive_queue);
77 log_debug("mptp_release sock=%p\n", sk);
83 static int mptp_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
85 struct sockaddr_mptp *mptp_addr;
86 struct mptp_sock *ssk;
90 if (unlikely(addr_len < sizeof(struct sockaddr_mptp) + sizeof(struct mptp_dest))) {
91 log_error("Invalid size for sockaddr (%d)\n", addr_len);
96 mptp_addr = (struct sockaddr_mptp *) addr;
98 log_debug("Bind received port=%u (network order)\n", mptp_addr->dests[0].port);
99 port = ntohs(mptp_addr->dests[0].port);
101 port = get_next_free_port();
103 if (unlikely(port == 0 || port >= MAX_MPTP_PORT)) {
104 log_error("Invalid value for sockaddr port (%u)\n", port);
109 if (unlikely(mptp_lookup(port) != NULL)) {
110 log_error("Port %u already in use\n", port);
115 ssk = mptp_sk(sock->sk);
116 sock->sk->sk_rcvbuf = 10 * 1024 * 1024;
119 mptp_hash(port, ssk);
121 log_debug("Socket %p bound to port %u\n", ssk, port);
129 static int mptp_connect(struct socket *sock, struct sockaddr *addr, int addr_len, int flags)
133 struct inet_sock * isk;
134 struct mptp_sock * ssk;
136 log_debug("mptp_connect\n");
138 if (unlikely(sock == NULL)) {
139 log_error("Sock is NULL\n");
145 if (unlikely(sk == NULL)) {
146 log_error("Sock->sk is NULL\n");
154 if (unlikely(ssk->src != 0)) {
155 log_error("ssk->src is not NULL\n");
161 struct sockaddr_mptp * mptp_addr = (struct sockaddr_mptp *) addr;
163 if (unlikely(addr_len < sizeof(*mptp_addr) ||
164 addr_len < mptp_addr->count * sizeof(struct mptp_dest) ||
165 mptp_addr->count <= 0)) {
166 log_error("Invalid size or address family\n");
170 ssk->dst = ntohs(mptp_addr->dests[0].port);
171 if (unlikely(ssk->dst == 0 || ssk->dst >= MAX_MPTP_PORT)) {
172 log_error("Invalid value for destination port(%u)\n", ssk->dst);
177 isk->inet_daddr = mptp_addr->dests[0].addr;
178 log_debug("Received from user space destination port=%u and address=%u\n", ssk->dst, isk->inet_daddr);
180 log_error("Invalid mptp_addr (NULL)\n");
185 ssk->src = get_next_free_port();
186 if (unlikely(ssk->src == 0)) {
187 log_error("No free ports\n");
192 mptp_hash(ssk->src, ssk);
200 static int mptp_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len)
206 struct sk_buff * skb;
208 struct inet_sock * isk;
209 struct mptp_sock * ssk;
210 struct mptphdr * shdr;
213 struct rtable * rt = NULL;
216 struct sockaddr_mptp * mptp_addr = NULL;
219 if (unlikely(sock == NULL)) {
220 log_error("Sock is NULL\n");
226 if (unlikely(sk == NULL)) {
227 log_error("Sock->sk is NULL\n");
237 sport = get_next_free_port();
238 if (unlikely(sport == 0)) {
239 log_error("No free ports\n");
246 mptp_addr = (struct sockaddr_mptp *) msg->msg_name;
248 if (unlikely(msg->msg_namelen < sizeof(*mptp_addr) + mptp_addr->count * sizeof(struct mptp_dest) ||
249 mptp_addr->count <= 0)) {
250 log_error("Invalid size for msg_name (size=%u, addr_count=%u)\n", msg->msg_namelen, mptp_addr->count);
255 dests = mptp_addr->count;
258 if (unlikely(!ssk->dst || !isk->inet_daddr)) {
259 log_error("No destination port/address\n");
264 daddr = isk->inet_daddr;
266 log_debug("Got from socket destination port=%u and address=%u\n", dport, daddr);
270 if (msg->msg_iovlen < dests)
271 dests = msg->msg_iovlen;
273 for (i = 0; i < dests; i++) {
274 struct mptp_dest *dest = &mptp_addr->dests[i];
275 struct iovec *iov = &msg->msg_iov[i];
278 dport = ntohs(dest->port);
279 if (unlikely(dport == 0 || dport >= MAX_MPTP_PORT)) {
280 log_error("Invalid value for destination port(%u)\n", dport);
286 log_debug("Received from user space destination port=%u and address=%u\n", dport, daddr);
289 totlen = len + sizeof(struct mptphdr) + sizeof(struct iphdr);
290 skb = sock_alloc_send_skb(sk, totlen, msg->msg_flags & MSG_DONTWAIT, &err);
291 if (unlikely(!skb)) {
292 log_error("sock_alloc_send_skb failed\n");
295 log_debug("Allocated %u bytes for skb (payload size=%u)\n", totlen, len);
297 skb_reset_network_header(skb);
298 skb_reserve(skb, sizeof(struct iphdr));
299 log_debug("Reseted network header\n");
300 skb_reset_transport_header(skb);
301 skb_put(skb, sizeof(struct mptphdr));
302 log_debug("Reseted transport header\n");
304 shdr = (struct mptphdr *) skb_transport_header(skb);
305 shdr->dst = htons(dport);
306 shdr->src = htons(sport);
307 shdr->len = htons(len + sizeof(struct mptphdr));
309 payload = skb_put(skb, len);
310 log_debug("payload=%p\n", payload);
312 err = skb_copy_datagram_from_iovec(skb, sizeof(struct mptphdr), iov, 0, len);
314 log_error("skb_copy_datagram_from_iovec failed\n");
317 log_debug("Copied %u bytes into the skb\n", len);
320 rt = (struct rtable *) __sk_dst_check(sk, 0);
323 struct flowi fl = { .fl4_dst = daddr,
324 .proto = sk->sk_protocol,
325 .flags = inet_sk_flowi_flags(sk),
327 err = ip_route_output_flow(sock_net(sk), &rt, &fl, sk, 0);
329 log_error("Route lookup failed\n");
332 #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 36)
333 sk_dst_set(sk, dst_clone(&rt->u.dst));
335 sk_dst_set(sk, dst_clone(&rt->dst));
340 err = ip_queue_xmit(skb);
342 log_debug("Sent %u bytes on wire\n", len);
346 log_error("ip_queue_xmit failed\n");
360 static int mptp_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t len, int flags)
363 struct sockaddr_mptp *mptp_addr;
364 struct sock * sk = sock->sk;
367 struct sockaddr_mptp *ret_addr = (struct sockaddr_mptp *) msg->msg_name;
370 log_debug("Trying to receive sock=%p sk=%p flags=%d\n", sock, sk, flags);
372 skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
373 if (unlikely(!skb)) {
374 log_error("skb_recv_datagram failed with %d\n", err);
378 for (i = 0; i < msg->msg_iovlen; i++) {
379 log_debug("Received skb %p\n", skb);
381 mptp_addr = (struct sockaddr_mptp *) skb->cb;
384 if (copied > msg->msg_iov[i].iov_len) {
385 copied = msg->msg_iov[i].iov_len;
386 msg->msg_flags |= MSG_TRUNC;
389 err = skb_copy_datagram_iovec(skb, 0, &msg->msg_iov[i], copied);
391 log_error("skb_copy_datagram_iovec\n");
394 log_debug("Received %d bytes\n", copied);
396 sock_recv_ts_and_drops(msg, sk, skb);
399 memcpy(&ret_addr->dests[i], &mptp_addr->dests[0], sizeof(ret_addr->dests[i]));
400 ret_addr->dests[i].bytes = copied;
406 skb_free_datagram(sk, skb);
408 if (i == msg->msg_iovlen - 1)
411 skb = skb_recv_datagram(sk, flags, 1, &err);
412 if (likely(err == -EAGAIN)) {
413 log_debug("No more skbs in the queue, returning...\n");
419 ret_addr->count = i + 1;
420 msg->msg_namelen = sizeof(struct sockaddr_mptp) + (i + 1) * sizeof(struct mptp_dest);
426 static int mptp_rcv(struct sk_buff *skb)
428 struct mptphdr *shdr;
429 struct mptp_sock *ssk;
432 struct sockaddr_mptp * mptp_addr;
434 int addr_size = sizeof(struct sockaddr_mptp) + sizeof(struct mptp_dest);
436 if (unlikely(!pskb_may_pull(skb, sizeof(struct mptphdr)))) {
437 log_error("Insufficient space for header\n");
441 shdr = (struct mptphdr *) skb->data;
442 len = ntohs(shdr->len);
444 if (unlikely(skb->len < len)) {
445 log_error("Malformed packet (packet_len=%u, skb_len=%u)\n", len, skb->len);
449 if (unlikely(len < sizeof(struct mptphdr))) {
450 log_error("Malformed packet (packet_len=%u sizeof(mptphdr)=%u\n", len, sizeof(struct mptphdr));
454 src = ntohs(shdr->src);
455 dst = ntohs(shdr->dst);
456 if (unlikely(src == 0 || dst == 0 || src >= MAX_MPTP_PORT || dst >= MAX_MPTP_PORT)) {
457 log_error("Malformed packet (src=%u, dst=%u)\n", shdr->src, shdr->dst);
461 skb_pull(skb, sizeof(struct mptphdr));
462 len -= sizeof(struct mptphdr);
466 log_debug("Received %u bytes from from port=%u to port=%u\n", len - sizeof(struct mptphdr), src, dst);
468 ssk = mptp_lookup(dst);
470 log_error("MPTP lookup failed for port %u\n", dst);
474 BUG_ON(addr_size > sizeof(skb->cb));
476 mptp_addr = (struct sockaddr_mptp *) skb->cb;
477 mptp_addr->dests[0].port = shdr->src;
478 mptp_addr->dests[0].addr = ip_hdr(skb)->saddr;
480 log_debug("Setting sin_port=%u, sin_addr=%u\n", ntohs(shdr->src), mptp_addr->dests[0].addr);
482 err = ip_queue_rcv_skb((struct sock *) &ssk->sock, skb);
484 log_error("ip_queue_rcv_skb failed with %d\n", err);
487 return NET_RX_SUCCESS;
494 static struct proto mptp_prot = {
495 .obj_size = sizeof(struct mptp_sock),
496 .owner = THIS_MODULE,
500 static const struct proto_ops mptp_ops = {
502 .owner = THIS_MODULE,
503 .release = mptp_release,
505 .connect = mptp_connect,
506 .socketpair = sock_no_socketpair,
507 .accept = sock_no_accept,
508 .getname = sock_no_getname,
509 .poll = datagram_poll,
510 .ioctl = sock_no_ioctl,
511 .listen = sock_no_listen,
512 .shutdown = sock_no_shutdown,
513 .setsockopt = sock_no_setsockopt,
514 .getsockopt = sock_no_getsockopt,
515 .sendmsg = mptp_sendmsg,
516 .recvmsg = mptp_recvmsg,
517 .mmap = sock_no_mmap,
518 .sendpage = sock_no_sendpage,
521 static const struct net_protocol mptp_protocol = {
527 static struct inet_protosw mptp_protosw = {
529 .protocol = IPPROTO_MPTP,
535 static int __init mptp_init(void)
539 rc = proto_register(&mptp_prot, 1);
541 log_error("Error registering mptp protocol\n");
545 rc = inet_add_protocol(&mptp_protocol, IPPROTO_MPTP);
547 log_error("Error adding mptp protocol\n");
551 inet_register_protosw(&mptp_protosw);
552 log_debug("MPTP entered\n");
557 proto_unregister(&mptp_prot);
563 static void __exit mptp_exit(void)
565 inet_unregister_protosw(&mptp_protosw);
567 inet_del_protocol(&mptp_protocol, IPPROTO_MPTP);
569 proto_unregister(&mptp_prot);
571 log_debug("MPTP exited\n");
574 module_init(mptp_init);
575 module_exit(mptp_exit);