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/*
* 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 1.63 2001/07/10 04:29:01 davem Exp $
*
* Authors: Ross Biro, <bir7@leland.Stanford.Edu>
* 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/system.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/fcntl.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/inet.h>
#include <linux/netdevice.h>
#include <linux/mroute.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/icmp.h>
#include <net/udp.h>
#include <net/raw.h>
#include <net/inet_common.h>
#include <net/checksum.h>
struct sock *raw_v4_htable[RAWV4_HTABLE_SIZE];
rwlock_t raw_v4_lock = RW_LOCK_UNLOCKED;
static void raw_v4_hash(struct sock *sk)
{
struct sock **skp = &raw_v4_htable[sk->num & (RAWV4_HTABLE_SIZE - 1)];
write_lock_bh(&raw_v4_lock);
if ((sk->next = *skp) != NULL)
(*skp)->pprev = &sk->next;
*skp = sk;
sk->pprev = skp;
sock_prot_inc_use(sk->prot);
sock_hold(sk);
write_unlock_bh(&raw_v4_lock);
}
static void raw_v4_unhash(struct sock *sk)
{
write_lock_bh(&raw_v4_lock);
if (sk->pprev) {
if (sk->next)
sk->next->pprev = sk->pprev;
*sk->pprev = sk->next;
sk->pprev = NULL;
sock_prot_dec_use(sk->prot);
__sock_put(sk);
}
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 sock *s = sk;
for (s = sk; s; s = s->next) {
if (s->num == num &&
!(s->daddr && s->daddr != raddr) &&
!(s->rcv_saddr && s->rcv_saddr != laddr) &&
!(s->bound_dev_if && s->bound_dev_if != dif))
break; /* gotcha */
}
return s;
}
/*
* 0 - deliver
* 1 - block
*/
static __inline__ int icmp_filter(struct sock *sk, struct sk_buff *skb)
{
int type;
type = skb->h.icmph->type;
if (type < 32) {
__u32 data = sk->tp_pinfo.tp_raw4.filter.data;
return ((1 << type) & data) != 0;
}
/* Do not block unknown ICMP types */
return 0;
}
/* IP input processing comes here for RAW socket delivery.
* This is fun as to avoid copies we want to make no surplus
* copies.
*
* RFC 1122: SHOULD pass TOS value up to the transport layer.
* -> It does. And not only TOS, but all IP header.
*/
struct sock *raw_v4_input(struct sk_buff *skb, struct iphdr *iph, int hash)
{
struct sock *sk;
read_lock(&raw_v4_lock);
if ((sk = raw_v4_htable[hash]) == NULL)
goto out;
sk = __raw_v4_lookup(sk, iph->protocol,
iph->saddr, iph->daddr,
skb->dev->ifindex);
while (sk) {
struct sock *sknext = __raw_v4_lookup(sk->next, iph->protocol,
iph->saddr, iph->daddr,
skb->dev->ifindex);
if (iph->protocol != IPPROTO_ICMP ||
!icmp_filter(sk, skb)) {
struct sk_buff *clone;
if (!sknext)
break;
clone = skb_clone(skb, GFP_ATOMIC);
/* Not releasing hash table! */
if (clone)
raw_rcv(sk, clone);
}
sk = sknext;
}
out:
if (sk)
sock_hold(sk);
read_unlock(&raw_v4_lock);
return sk;
}
void raw_err (struct sock *sk, struct sk_buff *skb, u32 info)
{
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 (!sk->protinfo.af_inet.recverr && 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 = sk->protinfo.af_inet.pmtudisc !=
IP_PMTUDISC_DONT;
err = EMSGSIZE;
}
}
if (sk->protinfo.af_inet.recverr) {
struct iphdr *iph = (struct iphdr*)skb->data;
u8 *payload = skb->data + (iph->ihl << 2);
if (sk->protinfo.af_inet.hdrincl)
payload = skb->data;
ip_icmp_error(sk, skb, err, 0, info, payload);
}
if (sk->protinfo.af_inet.recverr || harderr) {
sk->err = err;
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) {
IP_INC_STATS(IpInDiscards);
kfree_skb(skb);
return NET_RX_DROP;
}
IP_INC_STATS(IpInDelivers);
return NET_RX_SUCCESS;
}
int raw_rcv(struct sock *sk, struct sk_buff *skb)
{
skb_push(skb, skb->data - skb->nh.raw);
raw_rcv_skb(sk, skb);
return 0;
}
struct rawfakehdr
{
struct iovec *iov;
u32 saddr;
struct dst_entry *dst;
};
/*
* Send a RAW IP packet.
*/
/*
* Callback support is trivial for SOCK_RAW
*/
static int raw_getfrag(const void *p, char *to, unsigned int offset,
unsigned int fraglen)
{
struct rawfakehdr *rfh = (struct rawfakehdr *) p;
return memcpy_fromiovecend(to, rfh->iov, offset, fraglen);
}
/*
* IPPROTO_RAW needs extra work.
*/
static int raw_getrawfrag(const void *p, char *to, unsigned int offset,
unsigned int fraglen)
{
struct rawfakehdr *rfh = (struct rawfakehdr *) p;
if (memcpy_fromiovecend(to, rfh->iov, offset, fraglen))
return -EFAULT;
if (!offset) {
struct iphdr *iph = (struct iphdr *)to;
if (!iph->saddr)
iph->saddr = rfh->saddr;
iph->check = 0;
iph->tot_len = htons(fraglen); /* This is right as you can't
frag RAW packets */
/*
* Deliberate breach of modularity to keep
* ip_build_xmit clean (well less messy).
*/
if (!iph->id)
ip_select_ident(iph, rfh->dst, NULL);
iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
}
return 0;
}
static int raw_sendmsg(struct sock *sk, struct msghdr *msg, int len)
{
struct ipcm_cookie ipc;
struct rawfakehdr rfh;
struct rtable *rt = NULL;
int free = 0;
u32 daddr;
u8 tos;
int err;
/* This check is ONLY to check for arithmetic overflow
on integer(!) len. Not more! Real check will be made
in ip_build_xmit --ANK
BTW socket.c -> af_*.c -> ... make multiple
invalid conversions size_t -> int. We MUST repair it f.e.
by replacing all of them with size_t and revise all
the places sort of len += sizeof(struct iphdr)
If len was ULONG_MAX-10 it would be cathastrophe --ANK
*/
err = -EMSGSIZE;
if (len < 0 || 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 = -EINVAL;
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 = -EINVAL;
if (sk->state != TCP_ESTABLISHED)
goto out;
daddr = sk->daddr;
}
ipc.addr = sk->saddr;
ipc.opt = NULL;
ipc.oif = sk->bound_dev_if;
if (msg->msg_controllen) {
err = ip_cmsg_send(msg, &ipc);
if (err)
goto out;
if (ipc.opt)
free = 1;
}
rfh.saddr = ipc.addr;
ipc.addr = daddr;
if (!ipc.opt)
ipc.opt = sk->protinfo.af_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 (sk->protinfo.af_inet.hdrincl)
goto done;
if (ipc.opt->srr) {
if (!daddr)
goto done;
daddr = ipc.opt->faddr;
}
}
tos = RT_TOS(sk->protinfo.af_inet.tos) | sk->localroute;
if (msg->msg_flags & MSG_DONTROUTE)
tos |= RTO_ONLINK;
if (MULTICAST(daddr)) {
if (!ipc.oif)
ipc.oif = sk->protinfo.af_inet.mc_index;
if (!rfh.saddr)
rfh.saddr = sk->protinfo.af_inet.mc_addr;
}
err = ip_route_output(&rt, daddr, rfh.saddr, tos, ipc.oif);
if (err)
goto done;
err = -EACCES;
if (rt->rt_flags & RTCF_BROADCAST && !sk->broadcast)
goto done;
if (msg->msg_flags & MSG_CONFIRM)
goto do_confirm;
back_from_confirm:
rfh.iov = msg->msg_iov;
rfh.saddr = rt->rt_src;
rfh.dst = &rt->u.dst;
if (!ipc.addr)
ipc.addr = rt->rt_dst;
err = ip_build_xmit(sk, sk->protinfo.af_inet.hdrincl ? raw_getrawfrag :
raw_getfrag, &rfh, len, &ipc, rt, msg->msg_flags);
done:
if (free)
kfree(ipc.opt);
ip_rt_put(rt);
out: return err < 0 ? err : 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);
inet_sock_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 sockaddr_in *addr = (struct sockaddr_in *) uaddr;
int ret = -EINVAL;
int chk_addr_ret;
if (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;
sk->rcv_saddr = sk->saddr = addr->sin_addr.s_addr;
if (chk_addr_ret == RTN_MULTICAST || chk_addr_ret == RTN_BROADCAST)
sk->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.
*/
int raw_recvmsg(struct sock *sk, struct msghdr *msg, int len,
int noblock, int flags, int *addr_len)
{
int 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 (sk->protinfo.af_inet.cmsg_flags)
ip_cmsg_recv(msg, skb);
done:
skb_free_datagram(sk, skb);
out: return err ? : copied;
}
static int raw_init(struct sock *sk)
{
struct raw_opt *tp = &(sk->tp_pinfo.tp_raw4);
if (sk->num == IPPROTO_ICMP)
memset(&tp->filter, 0, sizeof(tp->filter));
return 0;
}
static int raw_seticmpfilter(struct sock *sk, char *optval, int optlen)
{
if (optlen > sizeof(struct icmp_filter))
optlen = sizeof(struct icmp_filter);
if (copy_from_user(&sk->tp_pinfo.tp_raw4.filter, optval, optlen))
return -EFAULT;
return 0;
}
static int raw_geticmpfilter(struct sock *sk, char *optval, int *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, &sk->tp_pinfo.tp_raw4.filter, len))
goto out;
ret = 0;
out: return ret;
}
static int raw_setsockopt(struct sock *sk, int level, int optname,
char *optval, int optlen)
{
if (level != SOL_RAW)
return ip_setsockopt(sk, level, optname, optval, optlen);
if (optname == ICMP_FILTER) {
if (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 *optval, int *optlen)
{
if (level != SOL_RAW)
return ip_getsockopt(sk, level, optname, optval, optlen);
if (optname == ICMP_FILTER) {
if (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->wmem_alloc);
return put_user(amount, (int *)arg);
}
case SIOCINQ: {
struct sk_buff *skb;
int amount = 0;
spin_lock_irq(&sk->receive_queue.lock);
skb = skb_peek(&sk->receive_queue);
if (skb != NULL)
amount = skb->len;
spin_unlock_irq(&sk->receive_queue.lock);
return put_user(amount, (int *)arg);
}
default:
#ifdef CONFIG_IP_MROUTE
return ipmr_ioctl(sk, cmd, arg);
#else
return -ENOIOCTLCMD;
#endif
}
}
static void get_raw_sock(struct sock *sp, char *tmpbuf, int i)
{
unsigned int dest = sp->daddr,
src = sp->rcv_saddr;
__u16 destp = 0,
srcp = sp->num;
sprintf(tmpbuf, "%4d: %08X:%04X %08X:%04X"
" %02X %08X:%08X %02X:%08lX %08X %5d %8d %ld %d %p",
i, src, srcp, dest, destp, sp->state,
atomic_read(&sp->wmem_alloc), atomic_read(&sp->rmem_alloc),
0, 0L, 0,
sock_i_uid(sp), 0,
sock_i_ino(sp),
atomic_read(&sp->refcnt), sp);
}
int raw_get_info(char *buffer, char **start, off_t offset, int length)
{
int len = 0, num = 0, i;
off_t pos = 128;
off_t begin;
char tmpbuf[129];
if (offset < 128)
len += sprintf(buffer, "%-127s\n",
" sl local_address rem_address st tx_queue "
"rx_queue tr tm->when retrnsmt uid timeout "
"inode");
read_lock(&raw_v4_lock);
for (i = 0; i < RAWV4_HTABLE_SIZE; i++) {
struct sock *sk;
for (sk = raw_v4_htable[i]; sk; sk = sk->next, num++) {
if (sk->family != PF_INET)
continue;
pos += 128;
if (pos <= offset)
continue;
get_raw_sock(sk, tmpbuf, i);
len += sprintf(buffer + len, "%-127s\n", tmpbuf);
if (len >= length)
goto out;
}
}
out:
read_unlock(&raw_v4_lock);
begin = len - (pos - offset);
*start = buffer + begin;
len -= begin;
if (len > length)
len = length;
if (len < 0)
len = 0;
return len;
}
struct proto raw_prot = {
name: "RAW",
close: raw_close,
connect: udp_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,
};
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