/* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * RAW - implementation of IP "raw" sockets. * * Version: $Id: raw.c,v 1.64 2002/02/01 22:01:04 davem Exp $ * * Authors: Ross Biro * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> * * Fixes: * Alan Cox : verify_area() fixed up * Alan Cox : ICMP error handling * Alan Cox : EMSGSIZE if you send too big a packet * Alan Cox : Now uses generic datagrams and shared * skbuff library. No more peek crashes, * no more backlogs * Alan Cox : Checks sk->broadcast. * Alan Cox : Uses skb_free_datagram/skb_copy_datagram * Alan Cox : Raw passes ip options too * Alan Cox : Setsocketopt added * Alan Cox : Fixed error return for broadcasts * Alan Cox : Removed wake_up calls * Alan Cox : Use ttl/tos * Alan Cox : Cleaned up old debugging * Alan Cox : Use new kernel side addresses * Arnt Gulbrandsen : Fixed MSG_DONTROUTE in raw sockets. * Alan Cox : BSD style RAW socket demultiplexing. * Alan Cox : Beginnings of mrouted support. * Alan Cox : Added IP_HDRINCL option. * Alan Cox : Skip broadcast check if BSDism set. * David S. Miller : New socket lookup architecture. * * This program 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 of the License, or (at your option) any later version. */ #include <linux/config.h> #include <asm/atomic.h> #include <asm/byteorder.h> #include <asm/current.h> #include <asm/uaccess.h> #include <asm/ioctls.h> #include <linux/types.h> #include <linux/stddef.h> #include <linux/slab.h> #include <linux/errno.h> #include <linux/aio.h> #include <linux/kernel.h> #include <linux/spinlock.h> #include <linux/sockios.h> #include <linux/socket.h> #include <linux/in.h> #include <linux/mroute.h> #include <linux/netdevice.h> #include <linux/in_route.h> #include <linux/route.h> #include <linux/tcp.h> #include <linux/skbuff.h> #include <net/dst.h> #include <net/sock.h> #include <linux/gfp.h> #include <linux/ip.h> #include <linux/net.h> #include <net/ip.h> #include <net/icmp.h> #include <net/udp.h> #include <net/raw.h> #include <net/snmp.h> #include <net/inet_common.h> #include <net/checksum.h> #include <net/xfrm.h> #include <linux/rtnetlink.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/netfilter.h> #include <linux/netfilter_ipv4.h> struct hlist_head raw_v4_htable[RAWV4_HTABLE_SIZE]; DEFINE_RWLOCK(raw_v4_lock); static void raw_v4_hash(struct sock *sk) { struct hlist_head *head = &raw_v4_htable[inet_sk(sk)->num & (RAWV4_HTABLE_SIZE - 1)]; write_lock_bh(&raw_v4_lock); sk_add_node(sk, head); sock_prot_inc_use(sk->sk_prot); write_unlock_bh(&raw_v4_lock); } static void raw_v4_unhash(struct sock *sk) { write_lock_bh(&raw_v4_lock); if (sk_del_node_init(sk)) sock_prot_dec_use(sk->sk_prot); write_unlock_bh(&raw_v4_lock); } struct sock *__raw_v4_lookup(struct sock *sk, unsigned short num, unsigned long raddr, unsigned long laddr, int dif) { struct hlist_node *node; sk_for_each_from(sk, node) { struct inet_sock *inet = inet_sk(sk); if (inet->num == num && !(inet->daddr && inet->daddr != raddr) && !(inet->rcv_saddr && inet->rcv_saddr != laddr) && !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif)) goto found; /* gotcha */ } sk = NULL; found: return sk; } /* * 0 - deliver * 1 - block */ static __inline__ int icmp_filter(struct sock *sk, struct sk_buff *skb) { int type; if (!pskb_may_pull(skb, sizeof(struct icmphdr))) return 1; type = skb->h.icmph->type; if (type < 32) { __u32 data = raw_sk(sk)->filter.data; return ((1 << type) & data) != 0; } /* Do not block unknown ICMP types */ return 0; } /* IP input processing comes here for RAW socket delivery. * Caller owns SKB, so we must make clones. * * RFC 1122: SHOULD pass TOS value up to the transport layer. * -> It does. And not only TOS, but all IP header. */ void raw_v4_input(struct sk_buff *skb, struct iphdr *iph, int hash) { struct sock *sk; struct hlist_head *head; read_lock(&raw_v4_lock); head = &raw_v4_htable[hash]; if (hlist_empty(head)) goto out; sk = __raw_v4_lookup(__sk_head(head), iph->protocol, iph->saddr, iph->daddr, skb->dev->ifindex); while (sk) { if (iph->protocol != IPPROTO_ICMP || !icmp_filter(sk, skb)) { struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC); /* Not releasing hash table! */ if (clone) raw_rcv(sk, clone); } sk = __raw_v4_lookup(sk_next(sk), iph->protocol, iph->saddr, iph->daddr, skb->dev->ifindex); } out: read_unlock(&raw_v4_lock); } void raw_err (struct sock *sk, struct sk_buff *skb, u32 info) { struct inet_sock *inet = inet_sk(sk); int type = skb->h.icmph->type; int code = skb->h.icmph->code; int err = 0; int harderr = 0; /* Report error on raw socket, if: 1. User requested ip_recverr. 2. Socket is connected (otherwise the error indication is useless without ip_recverr and error is hard. */ if (!inet->recverr && sk->sk_state != TCP_ESTABLISHED) return; switch (type) { default: case ICMP_TIME_EXCEEDED: err = EHOSTUNREACH; break; case ICMP_SOURCE_QUENCH: return; case ICMP_PARAMETERPROB: err = EPROTO; harderr = 1; break; case ICMP_DEST_UNREACH: err = EHOSTUNREACH; if (code > NR_ICMP_UNREACH) break; err = icmp_err_convert[code].errno; harderr = icmp_err_convert[code].fatal; if (code == ICMP_FRAG_NEEDED) { harderr = inet->pmtudisc != IP_PMTUDISC_DONT; err = EMSGSIZE; } } if (inet->recverr) { struct iphdr *iph = (struct iphdr*)skb->data; u8 *payload = skb->data + (iph->ihl << 2); if (inet->hdrincl) payload = skb->data; ip_icmp_error(sk, skb, err, 0, info, payload); } if (inet->recverr || harderr) { sk->sk_err = err; sk->sk_error_report(sk); } } static int raw_rcv_skb(struct sock * sk, struct sk_buff * skb) { /* Charge it to the socket. */ if (sock_queue_rcv_skb(sk, skb) < 0) { /* FIXME: increment a raw drops counter here */ kfree_skb(skb); return NET_RX_DROP; } return NET_RX_SUCCESS; } int raw_rcv(struct sock *sk, struct sk_buff *skb) { if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) { kfree_skb(skb); return NET_RX_DROP; } skb_push(skb, skb->data - skb->nh.raw); raw_rcv_skb(sk, skb); return 0; } static int raw_send_hdrinc(struct sock *sk, void *from, size_t length, struct rtable *rt, unsigned int flags) { struct inet_sock *inet = inet_sk(sk); int hh_len; struct iphdr *iph; struct sk_buff *skb; int err; if (length > rt->u.dst.dev->mtu) { ip_local_error(sk, EMSGSIZE, rt->rt_dst, inet->dport, rt->u.dst.dev->mtu); return -EMSGSIZE; } if (flags&MSG_PROBE) goto out; hh_len = LL_RESERVED_SPACE(rt->u.dst.dev); skb = sock_alloc_send_skb(sk, length+hh_len+15, flags&MSG_DONTWAIT, &err); if (skb == NULL) goto error; skb_reserve(skb, hh_len); skb->priority = sk->sk_priority; skb->dst = dst_clone(&rt->u.dst); skb->nh.iph = iph = (struct iphdr *)skb_put(skb, length); skb->ip_summed = CHECKSUM_NONE; skb->h.raw = skb->nh.raw; err = memcpy_fromiovecend((void *)iph, from, 0, length); if (err) goto error_fault; /* We don't modify invalid header */ if (length >= sizeof(*iph) && iph->ihl * 4U <= length) { if (!iph->saddr) iph->saddr = rt->rt_src; iph->check = 0; iph->tot_len = htons(length); if (!iph->id) ip_select_ident(iph, &rt->u.dst, NULL); iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); } err = NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev, dst_output); if (err > 0) err = inet->recverr ? net_xmit_errno(err) : 0; if (err) goto error; out: return 0; error_fault: err = -EFAULT; kfree_skb(skb); error: IP_INC_STATS(IPSTATS_MIB_OUTDISCARDS); return err; } static void raw_probe_proto_opt(struct flowi *fl, struct msghdr *msg) { struct iovec *iov; u8 __user *type = NULL; u8 __user *code = NULL; int probed = 0; unsigned int i; if (!msg->msg_iov) return; for (i = 0; i < msg->msg_iovlen; i++) { iov = &msg->msg_iov[i]; if (!iov) continue; switch (fl->proto) { case IPPROTO_ICMP: /* check if one-byte field is readable or not. */ if (iov->iov_base && iov->iov_len < 1) break; if (!type) { type = iov->iov_base; /* check if code field is readable or not. */ if (iov->iov_len > 1) code = type + 1; } else if (!code) code = iov->iov_base; if (type && code) { get_user(fl->fl_icmp_type, type); __get_user(fl->fl_icmp_code, code); probed = 1; } break; default: probed = 1; break; } if (probed) break; } } static int raw_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len) { struct inet_sock *inet = inet_sk(sk); struct ipcm_cookie ipc; struct rtable *rt = NULL; int free = 0; u32 daddr; u32 saddr; u8 tos; int err; err = -EMSGSIZE; if (len > 0xFFFF) goto out; /* * Check the flags. */ err = -EOPNOTSUPP; if (msg->msg_flags & MSG_OOB) /* Mirror BSD error message */ goto out; /* compatibility */ /* * Get and verify the address. */ if (msg->msg_namelen) { struct sockaddr_in *usin = (struct sockaddr_in*)msg->msg_name; err = -EINVAL; if (msg->msg_namelen < sizeof(*usin)) goto out; if (usin->sin_family != AF_INET) { static int complained; if (!complained++) printk(KERN_INFO "%s forgot to set AF_INET in " "raw sendmsg. Fix it!\n", current->comm); err = -EAFNOSUPPORT; if (usin->sin_family) goto out; } daddr = usin->sin_addr.s_addr; /* ANK: I did not forget to get protocol from port field. * I just do not know, who uses this weirdness. * IP_HDRINCL is much more convenient. */ } else { err = -EDESTADDRREQ; if (sk->sk_state != TCP_ESTABLISHED) goto out; daddr = inet->daddr; } ipc.addr = inet->saddr; ipc.opt = NULL; ipc.oif = sk->sk_bound_dev_if; if (msg->msg_controllen) { err = ip_cmsg_send(msg, &ipc); if (err) goto out; if (ipc.opt) free = 1; } saddr = ipc.addr; ipc.addr = daddr; if (!ipc.opt) ipc.opt = inet->opt; if (ipc.opt) { err = -EINVAL; /* Linux does not mangle headers on raw sockets, * so that IP options + IP_HDRINCL is non-sense. */ if (inet->hdrincl) goto done; if (ipc.opt->srr) { if (!daddr) goto done; daddr = ipc.opt->faddr; } } tos = RT_CONN_FLAGS(sk); if (msg->msg_flags & MSG_DONTROUTE) tos |= RTO_ONLINK; if (MULTICAST(daddr)) { if (!ipc.oif) ipc.oif = inet->mc_index; if (!saddr) saddr = inet->mc_addr; } { struct flowi fl = { .oif = ipc.oif, .nl_u = { .ip4_u = { .daddr = daddr, .saddr = saddr, .tos = tos } }, .proto = inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol, }; if (!inet->hdrincl) raw_probe_proto_opt(&fl, msg); err = ip_route_output_flow(&rt, &fl, sk, !(msg->msg_flags&MSG_DONTWAIT)); } if (err) goto done; err = -EACCES; if (rt->rt_flags & RTCF_BROADCAST && !sock_flag(sk, SOCK_BROADCAST)) goto done; if (msg->msg_flags & MSG_CONFIRM) goto do_confirm; back_from_confirm: if (inet->hdrincl) err = raw_send_hdrinc(sk, msg->msg_iov, len, rt, msg->msg_flags); else { if (!ipc.addr) ipc.addr = rt->rt_dst; lock_sock(sk); err = ip_append_data(sk, ip_generic_getfrag, msg->msg_iov, len, 0, &ipc, rt, msg->msg_flags); if (err) ip_flush_pending_frames(sk); else if (!(msg->msg_flags & MSG_MORE)) err = ip_push_pending_frames(sk); release_sock(sk); } done: if (free) kfree(ipc.opt); ip_rt_put(rt); out: if (err < 0) return err; return len; do_confirm: dst_confirm(&rt->u.dst); if (!(msg->msg_flags & MSG_PROBE) || len) goto back_from_confirm; err = 0; goto done; } static void raw_close(struct sock *sk, long timeout) { /* * Raw sockets may have direct kernel refereneces. Kill them. */ ip_ra_control(sk, 0, NULL); sk_common_release(sk); } /* This gets rid of all the nasties in af_inet. -DaveM */ static int raw_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len) { struct inet_sock *inet = inet_sk(sk); struct sockaddr_in *addr = (struct sockaddr_in *) uaddr; int ret = -EINVAL; int chk_addr_ret; if (sk->sk_state != TCP_CLOSE || addr_len < sizeof(struct sockaddr_in)) goto out; chk_addr_ret = inet_addr_type(addr->sin_addr.s_addr); ret = -EADDRNOTAVAIL; if (addr->sin_addr.s_addr && chk_addr_ret != RTN_LOCAL && chk_addr_ret != RTN_MULTICAST && chk_addr_ret != RTN_BROADCAST) goto out; inet->rcv_saddr = inet->saddr = addr->sin_addr.s_addr; if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST) inet->saddr = 0; /* Use device */ sk_dst_reset(sk); ret = 0; out: return ret; } /* * This should be easy, if there is something there * we return it, otherwise we block. */ static int raw_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, size_t len, int noblock, int flags, int *addr_len) { struct inet_sock *inet = inet_sk(sk); size_t copied = 0; int err = -EOPNOTSUPP; struct sockaddr_in *sin = (struct sockaddr_in *)msg->msg_name; struct sk_buff *skb; if (flags & MSG_OOB) goto out; if (addr_len) *addr_len = sizeof(*sin); if (flags & MSG_ERRQUEUE) { err = ip_recv_error(sk, msg, len); goto out; } skb = skb_recv_datagram(sk, flags, noblock, &err); if (!skb) goto out; copied = skb->len; if (len < copied) { msg->msg_flags |= MSG_TRUNC; copied = len; } err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied); if (err) goto done; sock_recv_timestamp(msg, sk, skb); /* Copy the address. */ if (sin) { sin->sin_family = AF_INET; sin->sin_addr.s_addr = skb->nh.iph->saddr; memset(&sin->sin_zero, 0, sizeof(sin->sin_zero)); } if (inet->cmsg_flags) ip_cmsg_recv(msg, skb); if (flags & MSG_TRUNC) copied = skb->len; done: skb_free_datagram(sk, skb); out: if (err) return err; return copied; } static int raw_init(struct sock *sk) { struct raw_sock *rp = raw_sk(sk); if (inet_sk(sk)->num == IPPROTO_ICMP) memset(&rp->filter, 0, sizeof(rp->filter)); return 0; } static int raw_seticmpfilter(struct sock *sk, char __user *optval, int optlen) { if (optlen > sizeof(struct icmp_filter)) optlen = sizeof(struct icmp_filter); if (copy_from_user(&raw_sk(sk)->filter, optval, optlen)) return -EFAULT; return 0; } static int raw_geticmpfilter(struct sock *sk, char __user *optval, int __user *optlen) { int len, ret = -EFAULT; if (get_user(len, optlen)) goto out; ret = -EINVAL; if (len < 0) goto out; if (len > sizeof(struct icmp_filter)) len = sizeof(struct icmp_filter); ret = -EFAULT; if (put_user(len, optlen) || copy_to_user(optval, &raw_sk(sk)->filter, len)) goto out; ret = 0; out: return ret; } static int raw_setsockopt(struct sock *sk, int level, int optname, char __user *optval, int optlen) { if (level != SOL_RAW) return ip_setsockopt(sk, level, optname, optval, optlen); if (optname == ICMP_FILTER) { if (inet_sk(sk)->num != IPPROTO_ICMP) return -EOPNOTSUPP; else return raw_seticmpfilter(sk, optval, optlen); } return -ENOPROTOOPT; } static int raw_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { if (level != SOL_RAW) return ip_getsockopt(sk, level, optname, optval, optlen); if (optname == ICMP_FILTER) { if (inet_sk(sk)->num != IPPROTO_ICMP) return -EOPNOTSUPP; else return raw_geticmpfilter(sk, optval, optlen); } return -ENOPROTOOPT; } static int raw_ioctl(struct sock *sk, int cmd, unsigned long arg) { switch (cmd) { case SIOCOUTQ: { int amount = atomic_read(&sk->sk_wmem_alloc); return put_user(amount, (int __user *)arg); } case SIOCINQ: { struct sk_buff *skb; int amount = 0; spin_lock_bh(&sk->sk_receive_queue.lock); skb = skb_peek(&sk->sk_receive_queue); if (skb != NULL) amount = skb->len; spin_unlock_bh(&sk->sk_receive_queue.lock); return put_user(amount, (int __user *)arg); } default: #ifdef CONFIG_IP_MROUTE return ipmr_ioctl(sk, cmd, (void __user *)arg); #else return -ENOIOCTLCMD; #endif } } struct proto raw_prot = { .name = "RAW", .owner = THIS_MODULE, .close = raw_close, .connect = ip4_datagram_connect, .disconnect = udp_disconnect, .ioctl = raw_ioctl, .init = raw_init, .setsockopt = raw_setsockopt, .getsockopt = raw_getsockopt, .sendmsg = raw_sendmsg, .recvmsg = raw_recvmsg, .bind = raw_bind, .backlog_rcv = raw_rcv_skb, .hash = raw_v4_hash, .unhash = raw_v4_unhash, .obj_size = sizeof(struct raw_sock), }; #ifdef CONFIG_PROC_FS struct raw_iter_state { int bucket; }; #define raw_seq_private(seq) ((struct raw_iter_state *)(seq)->private) static struct sock *raw_get_first(struct seq_file *seq) { struct sock *sk; struct raw_iter_state* state = raw_seq_private(seq); for (state->bucket = 0; state->bucket < RAWV4_HTABLE_SIZE; ++state->bucket) { struct hlist_node *node; sk_for_each(sk, node, &raw_v4_htable[state->bucket]) if (sk->sk_family == PF_INET) goto found; } sk = NULL; found: return sk; } static struct sock *raw_get_next(struct seq_file *seq, struct sock *sk) { struct raw_iter_state* state = raw_seq_private(seq); do { sk = sk_next(sk); try_again: ; } while (sk && sk->sk_family != PF_INET); if (!sk && ++state->bucket < RAWV4_HTABLE_SIZE) { sk = sk_head(&raw_v4_htable[state->bucket]); goto try_again; } return sk; } static struct sock *raw_get_idx(struct seq_file *seq, loff_t pos) { struct sock *sk = raw_get_first(seq); if (sk) while (pos && (sk = raw_get_next(seq, sk)) != NULL) --pos; return pos ? NULL : sk; } static void *raw_seq_start(struct seq_file *seq, loff_t *pos) { read_lock(&raw_v4_lock); return *pos ? raw_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; } static void *raw_seq_next(struct seq_file *seq, void *v, loff_t *pos) { struct sock *sk; if (v == SEQ_START_TOKEN) sk = raw_get_first(seq); else sk = raw_get_next(seq, v); ++*pos; return sk; } static void raw_seq_stop(struct seq_file *seq, void *v) { read_unlock(&raw_v4_lock); } static __inline__ char *get_raw_sock(struct sock *sp, char *tmpbuf, int i) { struct inet_sock *inet = inet_sk(sp); unsigned int dest = inet->daddr, src = inet->rcv_saddr; __u16 destp = 0, srcp = inet->num; sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X" " %02X %08X:%08X %02X:%08lX %08X %5d %8d %lu %d %p", i, src, srcp, dest, destp, sp->sk_state, atomic_read(&sp->sk_wmem_alloc), atomic_read(&sp->sk_rmem_alloc), 0, 0L, 0, sock_i_uid(sp), 0, sock_i_ino(sp), atomic_read(&sp->sk_refcnt), sp); return tmpbuf; } static int raw_seq_show(struct seq_file *seq, void *v) { char tmpbuf[129]; if (v == SEQ_START_TOKEN) seq_printf(seq, "%-127s\n", " sl local_address rem_address st tx_queue " "rx_queue tr tm->when retrnsmt uid timeout " "inode"); else { struct raw_iter_state *state = raw_seq_private(seq); seq_printf(seq, "%-127s\n", get_raw_sock(v, tmpbuf, state->bucket)); } return 0; } static struct seq_operations raw_seq_ops = { .start = raw_seq_start, .next = raw_seq_next, .stop = raw_seq_stop, .show = raw_seq_show, }; static int raw_seq_open(struct inode *inode, struct file *file) { struct seq_file *seq; int rc = -ENOMEM; struct raw_iter_state *s = kmalloc(sizeof(*s), GFP_KERNEL); if (!s) goto out; rc = seq_open(file, &raw_seq_ops); if (rc) goto out_kfree; seq = file->private_data; seq->private = s; memset(s, 0, sizeof(*s)); out: return rc; out_kfree: kfree(s); goto out; } static struct file_operations raw_seq_fops = { .owner = THIS_MODULE, .open = raw_seq_open, .read = seq_read, .llseek = seq_lseek, .release = seq_release_private, }; int __init raw_proc_init(void) { if (!proc_net_fops_create("raw", S_IRUGO, &raw_seq_fops)) return -ENOMEM; return 0; } void __init raw_proc_exit(void) { proc_net_remove("raw"); } #endif /* CONFIG_PROC_FS */