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ip_sockglue.c
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ip_sockglue.c
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// SPDX-License-Identifier: GPL-2.0
/*
* 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.
*
* The IP to API glue.
*
* Authors: see ip.c
*
* Fixes:
* Many : Split from ip.c , see ip.c for history.
* Martin Mares : TOS setting fixed.
* Alan Cox : Fixed a couple of oopses in Martin's
* TOS tweaks.
* Mike McLagan : Routing by source
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/icmp.h>
#include <linux/inetdevice.h>
#include <linux/netdevice.h>
#include <linux/slab.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/tcp_states.h>
#include <linux/udp.h>
#include <linux/igmp.h>
#include <linux/netfilter.h>
#include <linux/route.h>
#include <linux/mroute.h>
#include <net/inet_ecn.h>
#include <net/route.h>
#include <net/xfrm.h>
#include <net/compat.h>
#include <net/checksum.h>
#if IS_ENABLED(CONFIG_IPV6)
#include <net/transp_v6.h>
#endif
#include <net/ip_fib.h>
#include <linux/errqueue.h>
#include <linux/uaccess.h>
#include <linux/bpfilter.h>
/*
* SOL_IP control messages.
*/
static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)
{
struct in_pktinfo info = *PKTINFO_SKB_CB(skb);
info.ipi_addr.s_addr = ip_hdr(skb)->daddr;
put_cmsg(msg, SOL_IP, IP_PKTINFO, sizeof(info), &info);
}
static void ip_cmsg_recv_ttl(struct msghdr *msg, struct sk_buff *skb)
{
int ttl = ip_hdr(skb)->ttl;
put_cmsg(msg, SOL_IP, IP_TTL, sizeof(int), &ttl);
}
static void ip_cmsg_recv_tos(struct msghdr *msg, struct sk_buff *skb)
{
put_cmsg(msg, SOL_IP, IP_TOS, 1, &ip_hdr(skb)->tos);
}
static void ip_cmsg_recv_opts(struct msghdr *msg, struct sk_buff *skb)
{
if (IPCB(skb)->opt.optlen == 0)
return;
put_cmsg(msg, SOL_IP, IP_RECVOPTS, IPCB(skb)->opt.optlen,
ip_hdr(skb) + 1);
}
static void ip_cmsg_recv_retopts(struct net *net, struct msghdr *msg,
struct sk_buff *skb)
{
unsigned char optbuf[sizeof(struct ip_options) + 40];
struct ip_options *opt = (struct ip_options *)optbuf;
if (IPCB(skb)->opt.optlen == 0)
return;
if (ip_options_echo(net, opt, skb)) {
msg->msg_flags |= MSG_CTRUNC;
return;
}
ip_options_undo(opt);
put_cmsg(msg, SOL_IP, IP_RETOPTS, opt->optlen, opt->__data);
}
static void ip_cmsg_recv_fragsize(struct msghdr *msg, struct sk_buff *skb)
{
int val;
if (IPCB(skb)->frag_max_size == 0)
return;
val = IPCB(skb)->frag_max_size;
put_cmsg(msg, SOL_IP, IP_RECVFRAGSIZE, sizeof(val), &val);
}
static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
int tlen, int offset)
{
__wsum csum = skb->csum;
if (skb->ip_summed != CHECKSUM_COMPLETE)
return;
if (offset != 0) {
int tend_off = skb_transport_offset(skb) + tlen;
csum = csum_sub(csum, skb_checksum(skb, tend_off, offset, 0));
}
put_cmsg(msg, SOL_IP, IP_CHECKSUM, sizeof(__wsum), &csum);
}
static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
{
char *secdata;
u32 seclen, secid;
int err;
err = security_socket_getpeersec_dgram(NULL, skb, &secid);
if (err)
return;
err = security_secid_to_secctx(secid, &secdata, &seclen);
if (err)
return;
put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
security_release_secctx(secdata, seclen);
}
static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
{
__be16 _ports[2], *ports;
struct sockaddr_in sin;
/* All current transport protocols have the port numbers in the
* first four bytes of the transport header and this function is
* written with this assumption in mind.
*/
ports = skb_header_pointer(skb, skb_transport_offset(skb),
sizeof(_ports), &_ports);
if (!ports)
return;
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = ip_hdr(skb)->daddr;
sin.sin_port = ports[1];
memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
put_cmsg(msg, SOL_IP, IP_ORIGDSTADDR, sizeof(sin), &sin);
}
void ip_cmsg_recv_offset(struct msghdr *msg, struct sock *sk,
struct sk_buff *skb, int tlen, int offset)
{
struct inet_sock *inet = inet_sk(sk);
unsigned int flags = inet->cmsg_flags;
/* Ordered by supposed usage frequency */
if (flags & IP_CMSG_PKTINFO) {
ip_cmsg_recv_pktinfo(msg, skb);
flags &= ~IP_CMSG_PKTINFO;
if (!flags)
return;
}
if (flags & IP_CMSG_TTL) {
ip_cmsg_recv_ttl(msg, skb);
flags &= ~IP_CMSG_TTL;
if (!flags)
return;
}
if (flags & IP_CMSG_TOS) {
ip_cmsg_recv_tos(msg, skb);
flags &= ~IP_CMSG_TOS;
if (!flags)
return;
}
if (flags & IP_CMSG_RECVOPTS) {
ip_cmsg_recv_opts(msg, skb);
flags &= ~IP_CMSG_RECVOPTS;
if (!flags)
return;
}
if (flags & IP_CMSG_RETOPTS) {
ip_cmsg_recv_retopts(sock_net(sk), msg, skb);
flags &= ~IP_CMSG_RETOPTS;
if (!flags)
return;
}
if (flags & IP_CMSG_PASSSEC) {
ip_cmsg_recv_security(msg, skb);
flags &= ~IP_CMSG_PASSSEC;
if (!flags)
return;
}
if (flags & IP_CMSG_ORIGDSTADDR) {
ip_cmsg_recv_dstaddr(msg, skb);
flags &= ~IP_CMSG_ORIGDSTADDR;
if (!flags)
return;
}
if (flags & IP_CMSG_CHECKSUM)
ip_cmsg_recv_checksum(msg, skb, tlen, offset);
if (flags & IP_CMSG_RECVFRAGSIZE)
ip_cmsg_recv_fragsize(msg, skb);
}
EXPORT_SYMBOL(ip_cmsg_recv_offset);
int ip_cmsg_send(struct sock *sk, struct msghdr *msg, struct ipcm_cookie *ipc,
bool allow_ipv6)
{
int err, val;
struct cmsghdr *cmsg;
struct net *net = sock_net(sk);
for_each_cmsghdr(cmsg, msg) {
if (!CMSG_OK(msg, cmsg))
return -EINVAL;
#if IS_ENABLED(CONFIG_IPV6)
if (allow_ipv6 &&
cmsg->cmsg_level == SOL_IPV6 &&
cmsg->cmsg_type == IPV6_PKTINFO) {
struct in6_pktinfo *src_info;
if (cmsg->cmsg_len < CMSG_LEN(sizeof(*src_info)))
return -EINVAL;
src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
if (!ipv6_addr_v4mapped(&src_info->ipi6_addr))
return -EINVAL;
if (src_info->ipi6_ifindex)
ipc->oif = src_info->ipi6_ifindex;
ipc->addr = src_info->ipi6_addr.s6_addr32[3];
continue;
}
#endif
if (cmsg->cmsg_level == SOL_SOCKET) {
err = __sock_cmsg_send(sk, msg, cmsg, &ipc->sockc);
if (err)
return err;
continue;
}
if (cmsg->cmsg_level != SOL_IP)
continue;
switch (cmsg->cmsg_type) {
case IP_RETOPTS:
err = cmsg->cmsg_len - sizeof(struct cmsghdr);
/* Our caller is responsible for freeing ipc->opt */
err = ip_options_get(net, &ipc->opt,
KERNEL_SOCKPTR(CMSG_DATA(cmsg)),
err < 40 ? err : 40);
if (err)
return err;
break;
case IP_PKTINFO:
{
struct in_pktinfo *info;
if (cmsg->cmsg_len != CMSG_LEN(sizeof(struct in_pktinfo)))
return -EINVAL;
info = (struct in_pktinfo *)CMSG_DATA(cmsg);
if (info->ipi_ifindex)
ipc->oif = info->ipi_ifindex;
ipc->addr = info->ipi_spec_dst.s_addr;
break;
}
case IP_TTL:
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
return -EINVAL;
val = *(int *)CMSG_DATA(cmsg);
if (val < 1 || val > 255)
return -EINVAL;
ipc->ttl = val;
break;
case IP_TOS:
if (cmsg->cmsg_len == CMSG_LEN(sizeof(int)))
val = *(int *)CMSG_DATA(cmsg);
else if (cmsg->cmsg_len == CMSG_LEN(sizeof(u8)))
val = *(u8 *)CMSG_DATA(cmsg);
else
return -EINVAL;
if (val < 0 || val > 255)
return -EINVAL;
ipc->tos = val;
ipc->priority = rt_tos2priority(ipc->tos);
break;
case IP_PROTOCOL:
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
return -EINVAL;
val = *(int *)CMSG_DATA(cmsg);
if (val < 1 || val > 255)
return -EINVAL;
ipc->protocol = val;
break;
default:
return -EINVAL;
}
}
return 0;
}
static void ip_ra_destroy_rcu(struct rcu_head *head)
{
struct ip_ra_chain *ra = container_of(head, struct ip_ra_chain, rcu);
sock_put(ra->saved_sk);
kfree(ra);
}
int ip_ra_control(struct sock *sk, unsigned char on,
void (*destructor)(struct sock *))
{
struct ip_ra_chain *ra, *new_ra;
struct ip_ra_chain __rcu **rap;
struct net *net = sock_net(sk);
if (sk->sk_type != SOCK_RAW || inet_sk(sk)->inet_num == IPPROTO_RAW)
return -EINVAL;
new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL;
if (on && !new_ra)
return -ENOMEM;
mutex_lock(&net->ipv4.ra_mutex);
for (rap = &net->ipv4.ra_chain;
(ra = rcu_dereference_protected(*rap,
lockdep_is_held(&net->ipv4.ra_mutex))) != NULL;
rap = &ra->next) {
if (ra->sk == sk) {
if (on) {
mutex_unlock(&net->ipv4.ra_mutex);
kfree(new_ra);
return -EADDRINUSE;
}
/* dont let ip_call_ra_chain() use sk again */
ra->sk = NULL;
RCU_INIT_POINTER(*rap, ra->next);
mutex_unlock(&net->ipv4.ra_mutex);
if (ra->destructor)
ra->destructor(sk);
/*
* Delay sock_put(sk) and kfree(ra) after one rcu grace
* period. This guarantee ip_call_ra_chain() dont need
* to mess with socket refcounts.
*/
ra->saved_sk = sk;
call_rcu(&ra->rcu, ip_ra_destroy_rcu);
return 0;
}
}
if (!new_ra) {
mutex_unlock(&net->ipv4.ra_mutex);
return -ENOBUFS;
}
new_ra->sk = sk;
new_ra->destructor = destructor;
RCU_INIT_POINTER(new_ra->next, ra);
rcu_assign_pointer(*rap, new_ra);
sock_hold(sk);
mutex_unlock(&net->ipv4.ra_mutex);
return 0;
}
static void ipv4_icmp_error_rfc4884(const struct sk_buff *skb,
struct sock_ee_data_rfc4884 *out)
{
switch (icmp_hdr(skb)->type) {
case ICMP_DEST_UNREACH:
case ICMP_TIME_EXCEEDED:
case ICMP_PARAMETERPROB:
ip_icmp_error_rfc4884(skb, out, sizeof(struct icmphdr),
icmp_hdr(skb)->un.reserved[1] * 4);
}
}
void ip_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
__be16 port, u32 info, u8 *payload)
{
struct sock_exterr_skb *serr;
skb = skb_clone(skb, GFP_ATOMIC);
if (!skb)
return;
serr = SKB_EXT_ERR(skb);
serr->ee.ee_errno = err;
serr->ee.ee_origin = SO_EE_ORIGIN_ICMP;
serr->ee.ee_type = icmp_hdr(skb)->type;
serr->ee.ee_code = icmp_hdr(skb)->code;
serr->ee.ee_pad = 0;
serr->ee.ee_info = info;
serr->ee.ee_data = 0;
serr->addr_offset = (u8 *)&(((struct iphdr *)(icmp_hdr(skb) + 1))->daddr) -
skb_network_header(skb);
serr->port = port;
if (skb_pull(skb, payload - skb->data)) {
if (inet_sk(sk)->recverr_rfc4884)
ipv4_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884);
skb_reset_transport_header(skb);
if (sock_queue_err_skb(sk, skb) == 0)
return;
}
kfree_skb(skb);
}
void ip_local_error(struct sock *sk, int err, __be32 daddr, __be16 port, u32 info)
{
struct inet_sock *inet = inet_sk(sk);
struct sock_exterr_skb *serr;
struct iphdr *iph;
struct sk_buff *skb;
if (!inet->recverr)
return;
skb = alloc_skb(sizeof(struct iphdr), GFP_ATOMIC);
if (!skb)
return;
skb_put(skb, sizeof(struct iphdr));
skb_reset_network_header(skb);
iph = ip_hdr(skb);
iph->daddr = daddr;
serr = SKB_EXT_ERR(skb);
serr->ee.ee_errno = err;
serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
serr->ee.ee_type = 0;
serr->ee.ee_code = 0;
serr->ee.ee_pad = 0;
serr->ee.ee_info = info;
serr->ee.ee_data = 0;
serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
serr->port = port;
__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
skb_reset_transport_header(skb);
if (sock_queue_err_skb(sk, skb))
kfree_skb(skb);
}
/* For some errors we have valid addr_offset even with zero payload and
* zero port. Also, addr_offset should be supported if port is set.
*/
static inline bool ipv4_datagram_support_addr(struct sock_exterr_skb *serr)
{
return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
}
/* IPv4 supports cmsg on all imcp errors and some timestamps
*
* Timestamp code paths do not initialize the fields expected by cmsg:
* the PKTINFO fields in skb->cb[]. Fill those in here.
*/
static bool ipv4_datagram_support_cmsg(const struct sock *sk,
struct sk_buff *skb,
int ee_origin)
{
struct in_pktinfo *info;
if (ee_origin == SO_EE_ORIGIN_ICMP)
return true;
if (ee_origin == SO_EE_ORIGIN_LOCAL)
return false;
/* Support IP_PKTINFO on tstamp packets if requested, to correlate
* timestamp with egress dev. Not possible for packets without iif
* or without payload (SOF_TIMESTAMPING_OPT_TSONLY).
*/
info = PKTINFO_SKB_CB(skb);
if (!(sk->sk_tsflags & SOF_TIMESTAMPING_OPT_CMSG) ||
!info->ipi_ifindex)
return false;
info->ipi_spec_dst.s_addr = ip_hdr(skb)->saddr;
return true;
}
/*
* Handle MSG_ERRQUEUE
*/
int ip_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
{
struct sock_exterr_skb *serr;
struct sk_buff *skb;
DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
struct {
struct sock_extended_err ee;
struct sockaddr_in offender;
} errhdr;
int err;
int copied;
err = -EAGAIN;
skb = sock_dequeue_err_skb(sk);
if (!skb)
goto out;
copied = skb->len;
if (copied > len) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
err = skb_copy_datagram_msg(skb, 0, msg, copied);
if (unlikely(err)) {
kfree_skb(skb);
return err;
}
sock_recv_timestamp(msg, sk, skb);
serr = SKB_EXT_ERR(skb);
if (sin && ipv4_datagram_support_addr(serr)) {
sin->sin_family = AF_INET;
sin->sin_addr.s_addr = *(__be32 *)(skb_network_header(skb) +
serr->addr_offset);
sin->sin_port = serr->port;
memset(&sin->sin_zero, 0, sizeof(sin->sin_zero));
*addr_len = sizeof(*sin);
}
memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
sin = &errhdr.offender;
memset(sin, 0, sizeof(*sin));
if (ipv4_datagram_support_cmsg(sk, skb, serr->ee.ee_origin)) {
sin->sin_family = AF_INET;
sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
if (inet_sk(sk)->cmsg_flags)
ip_cmsg_recv(msg, skb);
}
put_cmsg(msg, SOL_IP, IP_RECVERR, sizeof(errhdr), &errhdr);
/* Now we could try to dump offended packet options */
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
consume_skb(skb);
out:
return err;
}
static void __ip_sock_set_tos(struct sock *sk, int val)
{
if (sk->sk_type == SOCK_STREAM) {
val &= ~INET_ECN_MASK;
val |= inet_sk(sk)->tos & INET_ECN_MASK;
}
if (inet_sk(sk)->tos != val) {
inet_sk(sk)->tos = val;
sk->sk_priority = rt_tos2priority(val);
sk_dst_reset(sk);
}
}
void ip_sock_set_tos(struct sock *sk, int val)
{
lock_sock(sk);
__ip_sock_set_tos(sk, val);
release_sock(sk);
}
EXPORT_SYMBOL(ip_sock_set_tos);
void ip_sock_set_freebind(struct sock *sk)
{
lock_sock(sk);
inet_sk(sk)->freebind = true;
release_sock(sk);
}
EXPORT_SYMBOL(ip_sock_set_freebind);
void ip_sock_set_recverr(struct sock *sk)
{
lock_sock(sk);
inet_sk(sk)->recverr = true;
release_sock(sk);
}
EXPORT_SYMBOL(ip_sock_set_recverr);
int ip_sock_set_mtu_discover(struct sock *sk, int val)
{
if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_OMIT)
return -EINVAL;
lock_sock(sk);
inet_sk(sk)->pmtudisc = val;
release_sock(sk);
return 0;
}
EXPORT_SYMBOL(ip_sock_set_mtu_discover);
void ip_sock_set_pktinfo(struct sock *sk)
{
lock_sock(sk);
inet_sk(sk)->cmsg_flags |= IP_CMSG_PKTINFO;
release_sock(sk);
}
EXPORT_SYMBOL(ip_sock_set_pktinfo);
/*
* Socket option code for IP. This is the end of the line after any
* TCP,UDP etc options on an IP socket.
*/
static bool setsockopt_needs_rtnl(int optname)
{
switch (optname) {
case IP_ADD_MEMBERSHIP:
case IP_ADD_SOURCE_MEMBERSHIP:
case IP_BLOCK_SOURCE:
case IP_DROP_MEMBERSHIP:
case IP_DROP_SOURCE_MEMBERSHIP:
case IP_MSFILTER:
case IP_UNBLOCK_SOURCE:
case MCAST_BLOCK_SOURCE:
case MCAST_MSFILTER:
case MCAST_JOIN_GROUP:
case MCAST_JOIN_SOURCE_GROUP:
case MCAST_LEAVE_GROUP:
case MCAST_LEAVE_SOURCE_GROUP:
case MCAST_UNBLOCK_SOURCE:
return true;
}
return false;
}
static int set_mcast_msfilter(struct sock *sk, int ifindex,
int numsrc, int fmode,
struct sockaddr_storage *group,
struct sockaddr_storage *list)
{
struct ip_msfilter *msf;
struct sockaddr_in *psin;
int err, i;
msf = kmalloc(IP_MSFILTER_SIZE(numsrc), GFP_KERNEL);
if (!msf)
return -ENOBUFS;
psin = (struct sockaddr_in *)group;
if (psin->sin_family != AF_INET)
goto Eaddrnotavail;
msf->imsf_multiaddr = psin->sin_addr.s_addr;
msf->imsf_interface = 0;
msf->imsf_fmode = fmode;
msf->imsf_numsrc = numsrc;
for (i = 0; i < numsrc; ++i) {
psin = (struct sockaddr_in *)&list[i];
if (psin->sin_family != AF_INET)
goto Eaddrnotavail;
msf->imsf_slist_flex[i] = psin->sin_addr.s_addr;
}
err = ip_mc_msfilter(sk, msf, ifindex);
kfree(msf);
return err;
Eaddrnotavail:
kfree(msf);
return -EADDRNOTAVAIL;
}
static int copy_group_source_from_sockptr(struct group_source_req *greqs,
sockptr_t optval, int optlen)
{
if (in_compat_syscall()) {
struct compat_group_source_req gr32;
if (optlen != sizeof(gr32))
return -EINVAL;
if (copy_from_sockptr(&gr32, optval, sizeof(gr32)))
return -EFAULT;
greqs->gsr_interface = gr32.gsr_interface;
greqs->gsr_group = gr32.gsr_group;
greqs->gsr_source = gr32.gsr_source;
} else {
if (optlen != sizeof(*greqs))
return -EINVAL;
if (copy_from_sockptr(greqs, optval, sizeof(*greqs)))
return -EFAULT;
}
return 0;
}
static int do_mcast_group_source(struct sock *sk, int optname,
sockptr_t optval, int optlen)
{
struct group_source_req greqs;
struct ip_mreq_source mreqs;
struct sockaddr_in *psin;
int omode, add, err;
err = copy_group_source_from_sockptr(&greqs, optval, optlen);
if (err)
return err;
if (greqs.gsr_group.ss_family != AF_INET ||
greqs.gsr_source.ss_family != AF_INET)
return -EADDRNOTAVAIL;
psin = (struct sockaddr_in *)&greqs.gsr_group;
mreqs.imr_multiaddr = psin->sin_addr.s_addr;
psin = (struct sockaddr_in *)&greqs.gsr_source;
mreqs.imr_sourceaddr = psin->sin_addr.s_addr;
mreqs.imr_interface = 0; /* use index for mc_source */
if (optname == MCAST_BLOCK_SOURCE) {
omode = MCAST_EXCLUDE;
add = 1;
} else if (optname == MCAST_UNBLOCK_SOURCE) {
omode = MCAST_EXCLUDE;
add = 0;
} else if (optname == MCAST_JOIN_SOURCE_GROUP) {
struct ip_mreqn mreq;
psin = (struct sockaddr_in *)&greqs.gsr_group;
mreq.imr_multiaddr = psin->sin_addr;
mreq.imr_address.s_addr = 0;
mreq.imr_ifindex = greqs.gsr_interface;
err = ip_mc_join_group_ssm(sk, &mreq, MCAST_INCLUDE);
if (err && err != -EADDRINUSE)
return err;
greqs.gsr_interface = mreq.imr_ifindex;
omode = MCAST_INCLUDE;
add = 1;
} else /* MCAST_LEAVE_SOURCE_GROUP */ {
omode = MCAST_INCLUDE;
add = 0;
}
return ip_mc_source(add, omode, sk, &mreqs, greqs.gsr_interface);
}
static int ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval, int optlen)
{
struct group_filter *gsf = NULL;
int err;
if (optlen < GROUP_FILTER_SIZE(0))
return -EINVAL;
if (optlen > READ_ONCE(sysctl_optmem_max))
return -ENOBUFS;
gsf = memdup_sockptr(optval, optlen);
if (IS_ERR(gsf))
return PTR_ERR(gsf);
/* numsrc >= (4G-140)/128 overflow in 32 bits */
err = -ENOBUFS;
if (gsf->gf_numsrc >= 0x1ffffff ||
gsf->gf_numsrc > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf))
goto out_free_gsf;
err = -EINVAL;
if (GROUP_FILTER_SIZE(gsf->gf_numsrc) > optlen)
goto out_free_gsf;
err = set_mcast_msfilter(sk, gsf->gf_interface, gsf->gf_numsrc,
gsf->gf_fmode, &gsf->gf_group,
gsf->gf_slist_flex);
out_free_gsf:
kfree(gsf);
return err;
}
static int compat_ip_set_mcast_msfilter(struct sock *sk, sockptr_t optval,
int optlen)
{
const int size0 = offsetof(struct compat_group_filter, gf_slist_flex);
struct compat_group_filter *gf32;
unsigned int n;
void *p;
int err;
if (optlen < size0)
return -EINVAL;
if (optlen > READ_ONCE(sysctl_optmem_max) - 4)
return -ENOBUFS;
p = kmalloc(optlen + 4, GFP_KERNEL);
if (!p)
return -ENOMEM;
gf32 = p + 4; /* we want ->gf_group and ->gf_slist_flex aligned */
err = -EFAULT;
if (copy_from_sockptr(gf32, optval, optlen))
goto out_free_gsf;
/* numsrc >= (4G-140)/128 overflow in 32 bits */
n = gf32->gf_numsrc;
err = -ENOBUFS;
if (n >= 0x1ffffff)
goto out_free_gsf;
err = -EINVAL;
if (offsetof(struct compat_group_filter, gf_slist_flex[n]) > optlen)
goto out_free_gsf;
/* numsrc >= (4G-140)/128 overflow in 32 bits */
err = -ENOBUFS;
if (n > READ_ONCE(sock_net(sk)->ipv4.sysctl_igmp_max_msf))
goto out_free_gsf;
err = set_mcast_msfilter(sk, gf32->gf_interface, n, gf32->gf_fmode,
&gf32->gf_group, gf32->gf_slist_flex);
out_free_gsf:
kfree(p);
return err;
}
static int ip_mcast_join_leave(struct sock *sk, int optname,
sockptr_t optval, int optlen)
{
struct ip_mreqn mreq = { };
struct sockaddr_in *psin;
struct group_req greq;
if (optlen < sizeof(struct group_req))
return -EINVAL;
if (copy_from_sockptr(&greq, optval, sizeof(greq)))
return -EFAULT;
psin = (struct sockaddr_in *)&greq.gr_group;
if (psin->sin_family != AF_INET)
return -EINVAL;
mreq.imr_multiaddr = psin->sin_addr;
mreq.imr_ifindex = greq.gr_interface;
if (optname == MCAST_JOIN_GROUP)
return ip_mc_join_group(sk, &mreq);
return ip_mc_leave_group(sk, &mreq);
}
static int compat_ip_mcast_join_leave(struct sock *sk, int optname,
sockptr_t optval, int optlen)
{
struct compat_group_req greq;
struct ip_mreqn mreq = { };
struct sockaddr_in *psin;
if (optlen < sizeof(struct compat_group_req))
return -EINVAL;
if (copy_from_sockptr(&greq, optval, sizeof(greq)))
return -EFAULT;
psin = (struct sockaddr_in *)&greq.gr_group;
if (psin->sin_family != AF_INET)
return -EINVAL;
mreq.imr_multiaddr = psin->sin_addr;
mreq.imr_ifindex = greq.gr_interface;
if (optname == MCAST_JOIN_GROUP)
return ip_mc_join_group(sk, &mreq);
return ip_mc_leave_group(sk, &mreq);
}
static int do_ip_setsockopt(struct sock *sk, int level, int optname,
sockptr_t optval, unsigned int optlen)
{
struct inet_sock *inet = inet_sk(sk);
struct net *net = sock_net(sk);
int val = 0, err;
bool needs_rtnl = setsockopt_needs_rtnl(optname);
switch (optname) {
case IP_PKTINFO:
case IP_RECVTTL:
case IP_RECVOPTS:
case IP_RECVTOS:
case IP_RETOPTS:
case IP_TOS:
case IP_TTL:
case IP_HDRINCL:
case IP_MTU_DISCOVER:
case IP_RECVERR:
case IP_ROUTER_ALERT:
case IP_FREEBIND:
case IP_PASSSEC:
case IP_TRANSPARENT:
case IP_MINTTL:
case IP_NODEFRAG:
case IP_BIND_ADDRESS_NO_PORT:
case IP_UNICAST_IF:
case IP_MULTICAST_TTL:
case IP_MULTICAST_ALL:
case IP_MULTICAST_LOOP:
case IP_RECVORIGDSTADDR:
case IP_CHECKSUM:
case IP_RECVFRAGSIZE:
case IP_RECVERR_RFC4884:
if (optlen >= sizeof(int)) {
if (copy_from_sockptr(&val, optval, sizeof(val)))
return -EFAULT;
} else if (optlen >= sizeof(char)) {
unsigned char ucval;
if (copy_from_sockptr(&ucval, optval, sizeof(ucval)))
return -EFAULT;
val = (int) ucval;
}
}
/* If optlen==0, it is equivalent to val == 0 */
if (optname == IP_ROUTER_ALERT)
return ip_ra_control(sk, val ? 1 : 0, NULL);
if (ip_mroute_opt(optname))
return ip_mroute_setsockopt(sk, optname, optval, optlen);
err = 0;
if (needs_rtnl)
rtnl_lock();
lock_sock(sk);
switch (optname) {
case IP_OPTIONS:
{
struct ip_options_rcu *old, *opt = NULL;
if (optlen > 40)
goto e_inval;
err = ip_options_get(sock_net(sk), &opt, optval, optlen);
if (err)
break;
old = rcu_dereference_protected(inet->inet_opt,
lockdep_sock_is_held(sk));
if (inet->is_icsk) {
struct inet_connection_sock *icsk = inet_csk(sk);
#if IS_ENABLED(CONFIG_IPV6)
if (sk->sk_family == PF_INET ||
(!((1 << sk->sk_state) &
(TCPF_LISTEN | TCPF_CLOSE)) &&
inet->inet_daddr != LOOPBACK4_IPV6)) {
#endif
if (old)
icsk->icsk_ext_hdr_len -= old->opt.optlen;
if (opt)
icsk->icsk_ext_hdr_len += opt->opt.optlen;
icsk->icsk_sync_mss(sk, icsk->icsk_pmtu_cookie);
#if IS_ENABLED(CONFIG_IPV6)
}
#endif
}
rcu_assign_pointer(inet->inet_opt, opt);
if (old)
kfree_rcu(old, rcu);
break;
}
case IP_PKTINFO:
if (val)
inet->cmsg_flags |= IP_CMSG_PKTINFO;
else
inet->cmsg_flags &= ~IP_CMSG_PKTINFO;
break;
case IP_RECVTTL:
if (val)
inet->cmsg_flags |= IP_CMSG_TTL;
else
inet->cmsg_flags &= ~IP_CMSG_TTL;
break;
case IP_RECVTOS: