Release 4.11 net/ipv4/raw.c

/*
 * 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.
 *
 * 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/types.h>
#include <linux/atomic.h>
#include <asm/byteorder.h>
#include <asm/current.h>
#include <linux/uaccess.h>
#include <asm/ioctls.h>
#include <linux/stddef.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/export.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/skbuff.h>
#include <linux/igmp.h>
#include <net/net_namespace.h>
#include <net/dst.h>
#include <net/sock.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/tcp_states.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>
#include <linux/compat.h>
#include <linux/uio.h>


struct raw_frag_vec {
	
struct msghdr *msg;
	union {
		
struct icmphdr icmph;
		
char c[1];
	} 
hdr;
	
int hlen;
};


struct raw_hashinfo raw_v4_hashinfo = {
	.lock = __RW_LOCK_UNLOCKED(raw_v4_hashinfo.lock),
};

EXPORT_SYMBOL_GPL(raw_v4_hashinfo);



int raw_hash_sk(struct sock *sk)
{
	struct raw_hashinfo *h = sk->sk_prot->h.raw_hash;
	struct hlist_head *head;

	head = &h->ht[inet_sk(sk)->inet_num & (RAW_HTABLE_SIZE - 1)];

	write_lock_bh(&h->lock);
	sk_add_node(sk, head);
	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
	write_unlock_bh(&h->lock);

	return 0;
}
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Pavel Emelyanov
35
39.33%
4
28.57%
Linus Torvalds (pre-git)
35
39.33%
4
28.57%
Arnaldo Carvalho de Melo
8
8.99%
2
14.29%
Craig Gallek
4
4.49%
1
7.14%
Eric Dumazet
4
4.49%
2
14.29%
David S. Miller
3
3.37%
1
7.14%
Total
89
100.00%
14
100.00%


EXPORT_SYMBOL_GPL(raw_hash_sk);



void raw_unhash_sk(struct sock *sk)
{
	struct raw_hashinfo *h = sk->sk_prot->h.raw_hash;

	write_lock_bh(&h->lock);
	if (sk_del_node_init(sk))
		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
	write_unlock_bh(&h->lock);
}
Contributors
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Pavel Emelyanov
57
93.44%
3
75.00%
Eric Dumazet
4
6.56%
1
25.00%
Total
61
100.00%
4
100.00%


EXPORT_SYMBOL_GPL(raw_unhash_sk);



struct sock *__raw_v4_lookup(struct net *net, struct sock *sk,
		unsigned short num, __be32 raddr, __be32 laddr, int dif)
{
	sk_for_each_from(sk) {
		struct inet_sock *inet = inet_sk(sk);

		if (net_eq(sock_net(sk), net) && inet->inet_num == num	&&
		    !(inet->inet_daddr && inet->inet_daddr != raddr) 	&&
		    !(inet->inet_rcv_saddr && inet->inet_rcv_saddr != laddr) &&
		    !(sk->sk_bound_dev_if && sk->sk_bound_dev_if != dif))
			goto found; /* gotcha */
	}
	sk = NULL;
found:
	return sk;
}
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Linus Torvalds (pre-git)
61
52.59%
4
30.77%
Arnaldo Carvalho de Melo
20
17.24%
3
23.08%
David S. Miller
13
11.21%
1
7.69%
Pavel Emelyanov
8
6.90%
1
7.69%
Hideaki Yoshifuji / 吉藤英明
7
6.03%
2
15.38%
Eric Dumazet
5
4.31%
1
7.69%
Alexey Dobriyan
2
1.72%
1
7.69%
Total
116
100.00%
13
100.00%


EXPORT_SYMBOL_GPL(__raw_v4_lookup);

/*
 *      0 - deliver
 *      1 - block
 */


static int icmp_filter(const struct sock *sk, const struct sk_buff *skb)
{
	struct icmphdr _hdr;
	const struct icmphdr *hdr;

	hdr = skb_header_pointer(skb, skb_transport_offset(skb),
				 sizeof(_hdr), &_hdr);
	if (!hdr)
		return 1;

	if (hdr->type < 32) {
		__u32 data = raw_sk(sk)->filter.data;

		return ((1U << hdr->type) & data) != 0;
	}

	/* Do not block unknown ICMP types */
	return 0;
}

Contributors
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CommitProp
Eric Dumazet
33
34.02%
1
16.67%
Linus Torvalds (pre-git)
31
31.96%
1
16.67%
Linus Torvalds
19
19.59%
1
16.67%
Ian Pratt
11
11.34%
1
16.67%
David S. Miller
2
2.06%
1
16.67%
Arnaldo Carvalho de Melo
1
1.03%
1
16.67%
Total
97
100.00%
6
100.00%

/* 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.
 */


static int raw_v4_input(struct sk_buff *skb, const struct iphdr *iph, int hash)
{
	struct sock *sk;
	struct hlist_head *head;
	int delivered = 0;
	struct net *net;

	read_lock(&raw_v4_hashinfo.lock);
	head = &raw_v4_hashinfo.ht[hash];
	if (hlist_empty(head))
		goto out;

	net = dev_net(skb->dev);
	sk = __raw_v4_lookup(net, __sk_head(head), iph->protocol,
			     iph->saddr, iph->daddr,
			     skb->dev->ifindex);

	while (sk) {
		delivered = 1;
		if ((iph->protocol != IPPROTO_ICMP || !icmp_filter(sk, skb)) &&
		    ip_mc_sf_allow(sk, iph->daddr, iph->saddr,
				   skb->dev->ifindex)) {
			struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);

			/* Not releasing hash table! */
			if (clone)
				raw_rcv(sk, clone);
		}
		sk = __raw_v4_lookup(net, sk_next(sk), iph->protocol,
				     iph->saddr, iph->daddr,
				     skb->dev->ifindex);
	}
out:
	read_unlock(&raw_v4_hashinfo.lock);
	return delivered;
}

Contributors
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CommitProp
Linus Torvalds (pre-git)
114
51.12%
3
23.08%
Pavel Emelyanov
25
11.21%
3
23.08%
David S. Miller
24
10.76%
1
7.69%
Arnaldo Carvalho de Melo
22
9.87%
2
15.38%
Quentin Armitage
21
9.42%
1
7.69%
Patrick McHardy
13
5.83%
1
7.69%
Hideaki Yoshifuji / 吉藤英明
3
1.35%
1
7.69%
Eric Dumazet
1
0.45%
1
7.69%
Total
223
100.00%
13
100.00%



int raw_local_deliver(struct sk_buff *skb, int protocol)
{
	int hash;
	struct sock *raw_sk;

	hash = protocol & (RAW_HTABLE_SIZE - 1);
	raw_sk = sk_head(&raw_v4_hashinfo.ht[hash]);

	/* If there maybe a raw socket we must check - if not we
         * don't care less
         */
	if (raw_sk && !raw_v4_input(skb, ip_hdr(skb), hash))
		raw_sk = NULL;

	return raw_sk != NULL;

}

Contributors
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Pavel Emelyanov
71
100.00%
2
100.00%
Total
71
100.00%
2
100.00%



static void raw_err(struct sock *sk, struct sk_buff *skb, u32 info)
{
	struct inet_sock *inet = inet_sk(sk);
	const int type = icmp_hdr(skb)->type;
	const int code = icmp_hdr(skb)->code;
	int err = 0;
	int harderr = 0;

	if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED)
		ipv4_sk_update_pmtu(skb, sk, info);
	else if (type == ICMP_REDIRECT) {
		ipv4_sk_redirect(skb, sk);
		return;
	}

	/* 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) {
		const struct iphdr *iph = (const 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);
	}
}

Contributors
Person
Tokens
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Commits
CommitProp
Linus Torvalds (pre-git)
173
60.70%
10
50.00%
Linus Torvalds
47
16.49%
1
5.00%
David S. Miller
47
16.49%
3
15.00%
Arnaldo Carvalho de Melo
12
4.21%
3
15.00%
Duan Jiong
3
1.05%
1
5.00%
Eric Dumazet
2
0.70%
1
5.00%
Pavel Emelyanov
1
0.35%
1
5.00%
Total
285
100.00%
20
100.00%



void raw_icmp_error(struct sk_buff *skb, int protocol, u32 info)
{
	int hash;
	struct sock *raw_sk;
	const struct iphdr *iph;
	struct net *net;

	hash = protocol & (RAW_HTABLE_SIZE - 1);

	read_lock(&raw_v4_hashinfo.lock);
	raw_sk = sk_head(&raw_v4_hashinfo.ht[hash]);
	if (raw_sk) {
		iph = (const struct iphdr *)skb->data;
		net = dev_net(skb->dev);

		while ((raw_sk = __raw_v4_lookup(net, raw_sk, protocol,
						iph->daddr, iph->saddr,
						skb->dev->ifindex)) != NULL) {
			raw_err(raw_sk, skb, info);
			raw_sk = sk_next(raw_sk);
			iph = (const struct iphdr *)skb->data;
		}
	}
	read_unlock(&raw_v4_hashinfo.lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Pavel Emelyanov
156
96.30%
3
60.00%
Eric Dumazet
3
1.85%
1
20.00%
Hideaki Yoshifuji / 吉藤英明
3
1.85%
1
20.00%
Total
162
100.00%
5
100.00%



static int raw_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
	/* Charge it to the socket. */

	ipv4_pktinfo_prepare(sk, skb);
	if (sock_queue_rcv_skb(sk, skb) < 0) {
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	return NET_RX_SUCCESS;
}

Contributors
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CommitProp
Linus Torvalds (pre-git)
40
83.33%
3
60.00%
Eric Dumazet
6
12.50%
1
20.00%
Shawn Bohrer
2
4.17%
1
20.00%
Total
48
100.00%
5
100.00%



int raw_rcv(struct sock *sk, struct sk_buff *skb)
{
	if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) {
		atomic_inc(&sk->sk_drops);
		kfree_skb(skb);
		return NET_RX_DROP;
	}
	nf_reset(skb);

	skb_push(skb, skb->data - skb_network_header(skb));

	raw_rcv_skb(sk, skb);
	return 0;
}

Contributors
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Tokens
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CommitProp
Linus Torvalds (pre-git)
32
43.24%
8
53.33%
Alexey Kuznetsov
20
27.03%
1
6.67%
Wang Chen
8
10.81%
1
6.67%
Patrick McHardy
5
6.76%
1
6.67%
Linus Torvalds
4
5.41%
1
6.67%
Arnaldo Carvalho de Melo
3
4.05%
1
6.67%
Hideaki Yoshifuji / 吉藤英明
1
1.35%
1
6.67%
David S. Miller
1
1.35%
1
6.67%
Total
74
100.00%
15
100.00%



static int raw_send_hdrinc(struct sock *sk, struct flowi4 *fl4,
			   struct msghdr *msg, size_t length,
			   struct rtable **rtp, unsigned int flags,
			   const struct sockcm_cookie *sockc)
{
	struct inet_sock *inet = inet_sk(sk);
	struct net *net = sock_net(sk);
	struct iphdr *iph;
	struct sk_buff *skb;
	unsigned int iphlen;
	int err;
	struct rtable *rt = *rtp;
	int hlen, tlen;

	if (length > rt->dst.dev->mtu) {
		ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport,
			       rt->dst.dev->mtu);
		return -EMSGSIZE;
	}
	if (flags&MSG_PROBE)
		goto out;

	hlen = LL_RESERVED_SPACE(rt->dst.dev);
	tlen = rt->dst.dev->needed_tailroom;
	skb = sock_alloc_send_skb(sk,
				  length + hlen + tlen + 15,
				  flags & MSG_DONTWAIT, &err);
	if (!skb)
		goto error;
	skb_reserve(skb, hlen);

	skb->priority = sk->sk_priority;
	skb->mark = sk->sk_mark;
	skb_dst_set(skb, &rt->dst);
	*rtp = NULL;

	skb_reset_network_header(skb);
	iph = ip_hdr(skb);
	skb_put(skb, length);

	skb->ip_summed = CHECKSUM_NONE;

	sock_tx_timestamp(sk, sockc->tsflags, &skb_shinfo(skb)->tx_flags);

	if (flags & MSG_CONFIRM)
		skb_set_dst_pending_confirm(skb, 1);

	skb->transport_header = skb->network_header;
	err = -EFAULT;
	if (memcpy_from_msg(iph, msg, length))
		goto error_free;

	iphlen = iph->ihl * 4;

	/*
         * We don't want to modify the ip header, but we do need to
         * be sure that it won't cause problems later along the network
         * stack.  Specifically we want to make sure that iph->ihl is a
         * sane value.  If ihl points beyond the length of the buffer passed
         * in, reject the frame as invalid
         */
	err = -EINVAL;
	if (iphlen > length)
		goto error_free;

	if (iphlen >= sizeof(*iph)) {
		if (!iph->saddr)
			iph->saddr = fl4->saddr;
		iph->check   = 0;
		iph->tot_len = htons(length);
		if (!iph->id)
			ip_select_ident(net, skb, NULL);

		iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
		skb->transport_header += iphlen;
		if (iph->protocol == IPPROTO_ICMP &&
		    length >= iphlen + sizeof(struct icmphdr))
			icmp_out_count(net, ((struct icmphdr *)
				skb_transport_header(skb))->type);
	}

	err = NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_OUT,
		      net, sk, skb, NULL, rt->dst.dev,
		      dst_output);
	if (err > 0)
		err = net_xmit_errno(err);
	if (err)
		goto error;
out:
	return 0;

error_free:
	kfree_skb(skb);
error:
	IP_INC_STATS(net, IPSTATS_MIB_OUTDISCARDS);
	if (err == -ENOBUFS && !inet->recverr)
		err = 0;
	return err;
}

Contributors
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CommitProp
Alexey Kuznetsov
208
38.66%
3
6.67%
Linus Torvalds (pre-git)
88
16.36%
8
17.78%
Herbert Xu
43
7.99%
2
4.44%
Eric Dumazet
35
6.51%
4
8.89%
David L Stevens
25
4.65%
1
2.22%
Neil Horman
22
4.09%
1
2.22%
Ben Cartwright-Cox
17
3.16%
1
2.22%
Arnaldo Carvalho de Melo
15
2.79%
5
11.11%
Pavel Emelyanov
14
2.60%
2
4.44%
Willem de Bruijn
13
2.42%
1
2.22%
Julian Anastasov
13
2.42%
1
2.22%
David S. Miller
11
2.04%
2
4.44%
Soheil Hassas Yeganeh
10
1.86%
1
2.22%
Tóth László Attila
7
1.30%
1
2.22%
Al Viro
5
0.93%
2
4.44%
Eric W. Biedermann
3
0.56%
2
4.44%
Hannes Frederic Sowa
2
0.37%
1
2.22%
Jan Engelhardt
1
0.19%
1
2.22%
Ansis Atteka
1
0.19%
1
2.22%
Linus Torvalds
1
0.19%
1
2.22%
Ian Morris
1
0.19%
1
2.22%
Hideaki Yoshifuji / 吉藤英明
1
0.19%
1
2.22%
Patrick McHardy
1
0.19%
1
2.22%
Jesper Juhl
1
0.19%
1
2.22%
Total
538
100.00%
45
100.00%



static int raw_probe_proto_opt(struct raw_frag_vec *rfv, struct flowi4 *fl4)
{
	int err;

	if (fl4->flowi4_proto != IPPROTO_ICMP)
		return 0;

	/* We only need the first two bytes. */
	rfv->hlen = 2;

	err = memcpy_from_msg(rfv->hdr.c, rfv->msg, rfv->hlen);
	if (err)
		return err;

	fl4->fl4_icmp_type = rfv->hdr.icmph.type;
	fl4->fl4_icmp_code = rfv->hdr.icmph.code;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Herbert Xu
48
53.33%
2
28.57%
Masahide Nakamura
30
33.33%
1
14.29%
Heiko Carstens
7
7.78%
1
14.29%
David S. Miller
3
3.33%
2
28.57%
Al Viro
2
2.22%
1
14.29%
Total
90
100.00%
7
100.00%



static int raw_getfrag(void *from, char *to, int offset, int len, int odd,
		       struct sk_buff *skb)
{
	struct raw_frag_vec *rfv = from;

	if (offset < rfv->hlen) {
		int copy = min(rfv->hlen - offset, len);

		if (skb->ip_summed == CHECKSUM_PARTIAL)
			memcpy(to, rfv->hdr.c + offset, copy);
		else
			skb->csum = csum_block_add(
				skb->csum,
				csum_partial_copy_nocheck(rfv->hdr.c + offset,
							  to, copy, 0),
				odd);

		odd = 0;
		offset += copy;
		to += copy;
		len -= copy;

		if (!len)
			return 0;
	}

	offset -= rfv->hlen;

	return ip_generic_getfrag(rfv->msg, to, offset, len, odd, skb);
}

Contributors
Person
Tokens
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Commits
CommitProp
Herbert Xu
160
99.38%
1
50.00%
Al Viro
1
0.62%
1
50.00%
Total
161
100.00%
2
100.00%



static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
{
	struct inet_sock *inet = inet_sk(sk);
	struct net *net = sock_net(sk);
	struct ipcm_cookie ipc;
	struct rtable *rt = NULL;
	struct flowi4 fl4;
	int free = 0;
	__be32 daddr;
	__be32 saddr;
	u8  tos;
	int err;
	struct ip_options_data opt_copy;
	struct raw_frag_vec rfv;

	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) {
		DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
		err = -EINVAL;
		if (msg->msg_namelen < sizeof(*usin))
			goto out;
		if (usin->sin_family != AF_INET) {
			pr_info_once("%s: %s forgot to set AF_INET. Fix it!\n",
				     __func__, 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->inet_daddr;
	}

	ipc.sockc.tsflags = sk->sk_tsflags;
	ipc.addr = inet->inet_saddr;
	ipc.opt = NULL;
	ipc.tx_flags = 0;
	ipc.ttl = 0;
	ipc.tos = -1;
	ipc.oif = sk->sk_bound_dev_if;

	if (msg->msg_controllen) {
		err = ip_cmsg_send(sk, msg, &ipc, false);
		if (unlikely(err)) {
			kfree(ipc.opt);
			goto out;
		}
		if (ipc.opt)
			free = 1;
	}

	saddr = ipc.addr;
	ipc.addr = daddr;

	if (!ipc.opt) {
		struct ip_options_rcu *inet_opt;

		rcu_read_lock();
		inet_opt = rcu_dereference(inet->inet_opt);
		if (inet_opt) {
			memcpy(&opt_copy, inet_opt,
			       sizeof(*inet_opt) + inet_opt->opt.optlen);
			ipc.opt = &opt_copy.opt;
		}
		rcu_read_unlock();
	}

	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->opt.srr) {
			if (!daddr)
				goto done;
			daddr = ipc.opt->opt.faddr;
		}
	}
	tos = get_rtconn_flags(&ipc, sk);
	if (msg->msg_flags & MSG_DONTROUTE)
		tos |= RTO_ONLINK;

	if (ipv4_is_multicast(daddr)) {
		if (!ipc.oif)
			ipc.oif = inet->mc_index;
		if (!saddr)
			saddr = inet->mc_addr;
	} else if (!ipc.oif)
		ipc.oif = inet->uc_index;

	flowi4_init_output(&fl4, ipc.oif, sk->sk_mark, tos,
			   RT_SCOPE_UNIVERSE,
			   inet->hdrincl ? IPPROTO_RAW : sk->sk_protocol,
			   inet_sk_flowi_flags(sk) |
			    (inet->hdrincl ? FLOWI_FLAG_KNOWN_NH : 0),
			   daddr, saddr, 0, 0, sk->sk_uid);

	if (!inet->hdrincl) {
		rfv.msg = msg;
		rfv.hlen = 0;

		err = raw_probe_proto_opt(&rfv, &fl4);
		if (err)
			goto done;
	}

	security_sk_classify_flow(sk, flowi4_to_flowi(&fl4));
	rt = ip_route_output_flow(net, &fl4, sk);
	if (IS_ERR(rt)) {
		err = PTR_ERR(rt);
		rt = NULL;
		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