/* setsockopt functions
* Copyright (C) 1999 Kunihiro Ishiguro
*
* This file is part of GNU Zebra.
*
* GNU Zebra 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, or (at your option) any
* later version.
*
* GNU Zebra is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; see the file COPYING; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <zebra.h>
#ifdef SUNOS_5
#include <ifaddrs.h>
#endif
#include "log.h"
#include "sockopt.h"
#include "sockunion.h"
#include "lib_errors.h"
void setsockopt_so_recvbuf(int sock, int size)
{
int orig_req = size;
while (setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &size, sizeof(size))
== -1)
size /= 2;
if (size != orig_req)
flog_err(EC_LIB_SOCKET,
"%s: fd %d: SO_RCVBUF set to %d (requested %d)",
__func__, sock, size, orig_req);
}
void setsockopt_so_sendbuf(const int sock, int size)
{
int orig_req = size;
while (setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &size, sizeof(size))
== -1)
size /= 2;
if (size != orig_req)
flog_err(EC_LIB_SOCKET,
"%s: fd %d: SO_SNDBUF set to %d (requested %d)",
__func__, sock, size, orig_req);
}
int getsockopt_so_sendbuf(const int sock)
{
uint32_t optval;
socklen_t optlen = sizeof(optval);
int ret = getsockopt(sock, SOL_SOCKET, SO_SNDBUF, (char *)&optval,
&optlen);
if (ret < 0) {
flog_err_sys(EC_LIB_SYSTEM_CALL,
"fd %d: can't getsockopt SO_SNDBUF: %d (%s)", sock,
errno, safe_strerror(errno));
return ret;
}
return optval;
}
int getsockopt_so_recvbuf(const int sock)
{
uint32_t optval;
socklen_t optlen = sizeof(optval);
int ret = getsockopt(sock, SOL_SOCKET, SO_RCVBUF, (char *)&optval,
&optlen);
if (ret < 0) {
flog_err_sys(EC_LIB_SYSTEM_CALL,
"fd %d: can't getsockopt SO_RCVBUF: %d (%s)", sock,
errno, safe_strerror(errno));
return ret;
}
return optval;
}
static void *getsockopt_cmsg_data(struct msghdr *msgh, int level, int type)
{
struct cmsghdr *cmsg;
for (cmsg = CMSG_FIRSTHDR(msgh); cmsg != NULL;
cmsg = CMSG_NXTHDR(msgh, cmsg))
if (cmsg->cmsg_level == level && cmsg->cmsg_type == type)
return CMSG_DATA(cmsg);
return NULL;
}
/* Set IPv6 packet info to the socket. */
int setsockopt_ipv6_pktinfo(int sock, int val)
{
int ret;
#ifdef IPV6_RECVPKTINFO /*2292bis-01*/
ret = setsockopt(sock, IPPROTO_IPV6, IPV6_RECVPKTINFO, &val,
sizeof(val));
if (ret < 0)
flog_err(EC_LIB_SOCKET,
"can't setsockopt IPV6_RECVPKTINFO : %s",
safe_strerror(errno));
#else /*RFC2292*/
ret = setsockopt(sock, IPPROTO_IPV6, IPV6_PKTINFO, &val, sizeof(val));
if (ret < 0)
flog_err(EC_LIB_SOCKET, "can't setsockopt IPV6_PKTINFO : %s",
safe_strerror(errno));
#endif /* INIA_IPV6 */
return ret;
}
/* Set multicast hops val to the socket. */
int setsockopt_ipv6_multicast_hops(int sock, int val)
{
int ret;
ret = setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val,
sizeof(val));
if (ret < 0)
flog_err(EC_LIB_SOCKET, "can't setsockopt IPV6_MULTICAST_HOPS");
return ret;
}
/* Set multicast hops val to the socket. */
int setsockopt_ipv6_unicast_hops(int sock, int val)
{
int ret;
ret = setsockopt(sock, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &val,
sizeof(val));
if (ret < 0)
flog_err(EC_LIB_SOCKET, "can't setsockopt IPV6_UNICAST_HOPS");
return ret;
}
int setsockopt_ipv6_hoplimit(int sock, int val)
{
int ret;
#ifdef IPV6_RECVHOPLIMIT /*2292bis-01*/
ret = setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, &val,
sizeof(val));
if (ret < 0)
flog_err(EC_LIB_SOCKET, "can't setsockopt IPV6_RECVHOPLIMIT");
#else /*RFC2292*/
ret = setsockopt(sock, IPPROTO_IPV6, IPV6_HOPLIMIT, &val, sizeof(val));
if (ret < 0)
flog_err(EC_LIB_SOCKET, "can't setsockopt IPV6_HOPLIMIT");
#endif
return ret;
}
/* Set multicast loop zero to the socket. */
int setsockopt_ipv6_multicast_loop(int sock, int val)
{
int ret;
ret = setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, &val,
sizeof(val));
if (ret < 0)
flog_err(EC_LIB_SOCKET, "can't setsockopt IPV6_MULTICAST_LOOP");
return ret;
}
static int getsockopt_ipv6_ifindex(struct msghdr *msgh)
{
struct in6_pktinfo *pktinfo;
pktinfo = getsockopt_cmsg_data(msgh, IPPROTO_IPV6, IPV6_PKTINFO);
return pktinfo->ipi6_ifindex;
}
int setsockopt_ipv6_tclass(int sock, int tclass)
{
int ret = 0;
#ifdef IPV6_TCLASS /* RFC3542 */
ret = setsockopt(sock, IPPROTO_IPV6, IPV6_TCLASS, &tclass,
sizeof(tclass));
if (ret < 0)
flog_err(EC_LIB_SOCKET,
"Can't set IPV6_TCLASS option for fd %d to %#x: %s",
sock, tclass, safe_strerror(errno));
#endif
return ret;
}
/*
* Process multicast socket options for IPv4 in an OS-dependent manner.
* Supported options are IP_{ADD,DROP}_MEMBERSHIP.
*
* Many operating systems have a limit on the number of groups that
* can be joined per socket (where each group and local address
* counts). This impacts OSPF, which joins groups on each interface
* using a single socket. The limit is typically 20, derived from the
* original BSD multicast implementation. Some systems have
* mechanisms for increasing this limit.
*
* In many 4.4BSD-derived systems, multicast group operations are not
* allowed on interfaces that are not UP. Thus, a previous attempt to
* leave the group may have failed, leaving it still joined, and we
* drop/join quietly to recover. This may not be necessary, but aims to
* defend against unknown behavior in that we will still return an error
* if the second join fails. It is not clear how other systems
* (e.g. Linux, Solaris) behave when leaving groups on down interfaces,
* but this behavior should not be harmful if they behave the same way,
* allow leaves, or implicitly leave all groups joined to down interfaces.
*/
int setsockopt_ipv4_multicast(int sock, int optname, struct in_addr if_addr,
unsigned int mcast_addr, ifindex_t ifindex)
{
#ifdef HAVE_RFC3678
struct group_req gr;
struct sockaddr_in *si;
int ret;
memset(&gr, 0, sizeof(gr));
si = (struct sockaddr_in *)&gr.gr_group;
gr.gr_interface = ifindex;
si->sin_family = AF_INET;
#ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
si->sin_len = sizeof(struct sockaddr_in);
#endif /* HAVE_STRUCT_SOCKADDR_IN_SIN_LEN */
si->sin_addr.s_addr = mcast_addr;
ret = setsockopt(sock, IPPROTO_IP,
(optname == IP_ADD_MEMBERSHIP) ? MCAST_JOIN_GROUP
: MCAST_LEAVE_GROUP,
(void *)&gr, sizeof(gr));
if ((ret < 0) && (optname == IP_ADD_MEMBERSHIP)
&& (errno == EADDRINUSE)) {
setsockopt(sock, IPPROTO_IP, MCAST_LEAVE_GROUP, (void *)&gr,
sizeof(gr));
ret = setsockopt(sock, IPPROTO_IP, MCAST_JOIN_GROUP,
(void *)&gr, sizeof(gr));
}
return ret;
#elif defined(HAVE_STRUCT_IP_MREQN_IMR_IFINDEX) && !defined(__FreeBSD__)
struct ip_mreqn mreqn;
int ret;
assert(optname == IP_ADD_MEMBERSHIP || optname == IP_DROP_MEMBERSHIP);
memset(&mreqn, 0, sizeof(mreqn));
mreqn.imr_multiaddr.s_addr = mcast_addr;
mreqn.imr_ifindex = ifindex;
ret = setsockopt(sock, IPPROTO_IP, optname, (void *)&mreqn,
sizeof(mreqn));
if ((ret < 0) && (optname == IP_ADD_MEMBERSHIP)
&& (errno == EADDRINUSE)) {
/* see above: handle possible problem when interface comes back
* up */
char buf[1][INET_ADDRSTRLEN];
zlog_info(
"setsockopt_ipv4_multicast attempting to drop and re-add (fd %d, mcast %s, ifindex %u)",
sock, inet_ntop(AF_INET, &mreqn.imr_multiaddr, buf[0],
sizeof(buf[0])),
ifindex);
setsockopt(sock, IPPROTO_IP, IP_DROP_MEMBERSHIP, (void *)&mreqn,
sizeof(mreqn));
ret = setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP,
(void *)&mreqn, sizeof(mreqn));
}
return ret;
/* Example defines for another OS, boilerplate off other code in this
function, AND handle optname as per other sections for consistency !! */
/* #elif defined(BOGON_NIX) && EXAMPLE_VERSION_CODE > -100000 */
/* Add your favourite OS here! */
#elif defined(HAVE_BSD_STRUCT_IP_MREQ_HACK) /* #if OS_TYPE */
/* standard BSD API */
struct ip_mreq mreq;
int ret;
assert(optname == IP_ADD_MEMBERSHIP || optname == IP_DROP_MEMBERSHIP);
memset(&mreq, 0, sizeof(mreq));
mreq.imr_multiaddr.s_addr = mcast_addr;
#if !defined __OpenBSD__
mreq.imr_interface.s_addr = htonl(ifindex);
#else
mreq.imr_interface.s_addr = if_addr.s_addr;
#endif
ret = setsockopt(sock, IPPROTO_IP, optname, (void *)&mreq,
sizeof(mreq));
if ((ret < 0) && (optname == IP_ADD_MEMBERSHIP)
&& (errno == EADDRINUSE)) {
/* see above: handle possible problem when interface comes back
* up */
char buf[1][INET_ADDRSTRLEN];
zlog_info(
"setsockopt_ipv4_multicast attempting to drop and re-add (fd %d, mcast %s, ifindex %u)",
sock, inet_ntop(AF_INET, &mreq.imr_multiaddr, buf[0],
sizeof(buf[0])),
ifindex);
setsockopt(sock, IPPROTO_IP, IP_DROP_MEMBERSHIP, (void *)&mreq,
sizeof(mreq));
ret = setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP,
(void *)&mreq, sizeof(mreq));
}
return ret;
#else
#error "Unsupported multicast API"
#endif /* #if OS_TYPE */
}
/*
* Set IP_MULTICAST_IF socket option in an OS-dependent manner.
*/
int setsockopt_ipv4_multicast_if(int sock, struct in_addr if_addr,
ifindex_t ifindex)
{
#ifdef HAVE_STRUCT_IP_MREQN_IMR_IFINDEX
struct ip_mreqn mreqn;
memset(&mreqn, 0, sizeof(mreqn));
mreqn.imr_ifindex = ifindex;
return setsockopt(sock, IPPROTO_IP, IP_MULTICAST_IF, (void *)&mreqn,
sizeof(mreqn));
/* Example defines for another OS, boilerplate off other code in this
function */
/* #elif defined(BOGON_NIX) && EXAMPLE_VERSION_CODE > -100000 */
/* Add your favourite OS here! */
#elif defined(HAVE_BSD_STRUCT_IP_MREQ_HACK)
struct in_addr m;
#if !defined __OpenBSD__
m.s_addr = htonl(ifindex);
#else
m.s_addr = if_addr.s_addr;
#endif
return setsockopt(sock, IPPROTO_IP, IP_MULTICAST_IF, (void *)&m,
sizeof(m));
#elif defined(SUNOS_5)
char ifname[IF_NAMESIZE];
struct ifaddrs *ifa, *ifap;
struct in_addr ifaddr;
if (if_indextoname(ifindex, ifname) == NULL)
return -1;
if (getifaddrs(&ifa) != 0)
return -1;
for (ifap = ifa; ifap != NULL; ifap = ifap->ifa_next) {
struct sockaddr_in *sa;
if (strcmp(ifap->ifa_name, ifname) != 0)
continue;
if (ifap->ifa_addr->sa_family != AF_INET)
continue;
sa = (struct sockaddr_in *)ifap->ifa_addr;
memcpy(&ifaddr, &sa->sin_addr, sizeof(ifaddr));
break;
}
freeifaddrs(ifa);
if (!ifap) /* This means we did not find an IP */
return -1;
return setsockopt(sock, IPPROTO_IP, IP_MULTICAST_IF, (void *)&ifaddr,
sizeof(ifaddr));
#else
#error "Unsupported multicast API"
#endif
}
int setsockopt_ipv4_multicast_loop(int sock, uint8_t val)
{
int ret;
ret = setsockopt(sock, IPPROTO_IP, IP_MULTICAST_LOOP, (void *)&val,
sizeof(val));
if (ret < 0)
flog_err(EC_LIB_SOCKET, "can't setsockopt IP_MULTICAST_LOOP");
return ret;
}
static int setsockopt_ipv4_ifindex(int sock, ifindex_t val)
{
int ret;
#if defined(IP_PKTINFO)
if ((ret = setsockopt(sock, IPPROTO_IP, IP_PKTINFO, &val, sizeof(val)))
< 0)
flog_err(EC_LIB_SOCKET,
"Can't set IP_PKTINFO option for fd %d to %d: %s",
sock, val, safe_strerror(errno));
#elif defined(IP_RECVIF)
if ((ret = setsockopt(sock, IPPROTO_IP, IP_RECVIF, &val, sizeof(val)))
< 0)
flog_err(EC_LIB_SOCKET,
"Can't set IP_RECVIF option for fd %d to %d: %s", sock,
val, safe_strerror(errno));
#else
#warning "Neither IP_PKTINFO nor IP_RECVIF is available."
#warning "Will not be able to receive link info."
#warning "Things might be seriously broken.."
/* XXX Does this ever happen? Should there be a zlog_warn message here?
*/
ret = -1;
#endif
return ret;
}
int setsockopt_ipv4_tos(int sock, int tos)
{
int ret;
ret = setsockopt(sock, IPPROTO_IP, IP_TOS, &tos, sizeof(tos));
if (ret < 0)
flog_err(EC_LIB_SOCKET,
"Can't set IP_TOS option for fd %d to %#x: %s", sock,
tos, safe_strerror(errno));
return ret;
}
int setsockopt_ifindex(int af, int sock, ifindex_t val)
{
int ret = -1;
switch (af) {
case AF_INET:
ret = setsockopt_ipv4_ifindex(sock, val);
break;
case AF_INET6:
ret = setsockopt_ipv6_pktinfo(sock, val);
break;
default:
flog_err(EC_LIB_DEVELOPMENT,
"setsockopt_ifindex: unknown address family %d", af);
}
return ret;
}
/*
* Requires: msgh is not NULL and points to a valid struct msghdr, which
* may or may not have control data about the incoming interface.
*
* Returns the interface index (small integer >= 1) if it can be
* determined, or else 0.
*/
static ifindex_t getsockopt_ipv4_ifindex(struct msghdr *msgh)
{
ifindex_t ifindex;
#if defined(IP_PKTINFO)
/* Linux pktinfo based ifindex retrieval */
struct in_pktinfo *pktinfo;
pktinfo = (struct in_pktinfo *)getsockopt_cmsg_data(msgh, IPPROTO_IP,
IP_PKTINFO);
/* getsockopt_ifindex() will forward this, being 0 "not found" */
if (pktinfo == NULL)
return 0;
ifindex = pktinfo->ipi_ifindex;
#elif defined(IP_RECVIF)
/* retrieval based on IP_RECVIF */
#ifndef SUNOS_5
/* BSD systems use a sockaddr_dl as the control message payload. */
struct sockaddr_dl *sdl;
#else
/* SUNOS_5 uses an integer with the index. */
ifindex_t *ifindex_p;
#endif /* SUNOS_5 */
#ifndef SUNOS_5
/* BSD */
sdl = (struct sockaddr_dl *)getsockopt_cmsg_data(msgh, IPPROTO_IP,
IP_RECVIF);
if (sdl != NULL)
ifindex = sdl->sdl_index;
else
ifindex = 0;
#else
/*
* Solaris. On Solaris 8, IP_RECVIF is defined, but the call to
* enable it fails with errno=99, and the struct msghdr has
* controllen 0.
*/
ifindex_p = (uint_t *)getsockopt_cmsg_data(msgh, IPPROTO_IP, IP_RECVIF);
if (ifindex_p != NULL)
ifindex = *ifindex_p;
else
ifindex = 0;
#endif /* SUNOS_5 */
#else
/*
* Neither IP_PKTINFO nor IP_RECVIF defined - warn at compile time.
* XXX Decide if this is a core service, or if daemons have to cope.
* Since Solaris 8 and OpenBSD seem not to provide it, it seems that
* daemons have to cope.
*/
#warning "getsockopt_ipv4_ifindex: Neither IP_PKTINFO nor IP_RECVIF defined."
#warning "Some daemons may fail to operate correctly!"
ifindex = 0;
#endif /* IP_PKTINFO */
return ifindex;
}
/* return ifindex, 0 if none found */
ifindex_t getsockopt_ifindex(int af, struct msghdr *msgh)
{
switch (af) {
case AF_INET:
return (getsockopt_ipv4_ifindex(msgh));
case AF_INET6:
return (getsockopt_ipv6_ifindex(msgh));
default:
flog_err(EC_LIB_DEVELOPMENT,
"getsockopt_ifindex: unknown address family %d", af);
return 0;
}
}
/* swab iph between order system uses for IP_HDRINCL and host order */
void sockopt_iphdrincl_swab_htosys(struct ip *iph)
{
/* BSD and derived take iph in network order, except for
* ip_len and ip_off
*/
#ifndef HAVE_IP_HDRINCL_BSD_ORDER
iph->ip_len = htons(iph->ip_len);
iph->ip_off = htons(iph->ip_off);
#endif /* HAVE_IP_HDRINCL_BSD_ORDER */
iph->ip_id = htons(iph->ip_id);
}
void sockopt_iphdrincl_swab_systoh(struct ip *iph)
{
#ifndef HAVE_IP_HDRINCL_BSD_ORDER
iph->ip_len = ntohs(iph->ip_len);
iph->ip_off = ntohs(iph->ip_off);
#endif /* HAVE_IP_HDRINCL_BSD_ORDER */
iph->ip_id = ntohs(iph->ip_id);
}
int sockopt_tcp_rtt(int sock)
{
#ifdef TCP_INFO
struct tcp_info ti;
socklen_t len = sizeof(ti);
if (getsockopt(sock, IPPROTO_TCP, TCP_INFO, &ti, &len) != 0)
return 0;
return ti.tcpi_rtt / 1000;
#else
return 0;
#endif
}
int sockopt_tcp_signature_ext(int sock, union sockunion *su, uint16_t prefixlen,
const char *password)
{
#ifndef HAVE_DECL_TCP_MD5SIG
/*
* We have been asked to enable MD5 auth for an address, but our
* platform doesn't support that
*/
return -2;
#endif
#ifndef TCP_MD5SIG_EXT
/*
* We have been asked to enable MD5 auth for a prefix, but our platform
* doesn't support that
*/
if (prefixlen > 0)
return -2;
#endif
#if HAVE_DECL_TCP_MD5SIG
int ret;
int optname = TCP_MD5SIG;
#ifndef GNU_LINUX
/*
* XXX Need to do PF_KEY operation here to add/remove an SA entry,
* and add/remove an SP entry for this peer's packet flows also.
*/
int md5sig = password && *password ? 1 : 0;
#else
int keylen = password ? strlen(password) : 0;
struct tcp_md5sig md5sig;
union sockunion *su2, *susock;
/* Figure out whether the socket and the sockunion are the same family..
* adding AF_INET to AF_INET6 needs to be v4 mapped, you'd think..
*/
if (!(susock = sockunion_getsockname(sock)))
return -1;
if (susock->sa.sa_family == su->sa.sa_family)
su2 = su;
else {
/* oops.. */
su2 = susock;
if (su2->sa.sa_family == AF_INET) {
sockunion_free(susock);
return 0;
}
/* If this does not work, then all users of this sockopt will
* need to
* differentiate between IPv4 and IPv6, and keep seperate
* sockets for
* each.
*
* Sadly, it doesn't seem to work at present. It's unknown
* whether
* this is a bug or not.
*/
if (su2->sa.sa_family == AF_INET6
&& su->sa.sa_family == AF_INET) {
su2->sin6.sin6_family = AF_INET6;
/* V4Map the address */
memset(&su2->sin6.sin6_addr, 0,
sizeof(struct in6_addr));
su2->sin6.sin6_addr.s6_addr32[2] = htonl(0xffff);
memcpy(&su2->sin6.sin6_addr.s6_addr32[3],
&su->sin.sin_addr, 4);
}
}
memset(&md5sig, 0, sizeof(md5sig));
memcpy(&md5sig.tcpm_addr, su2, sizeof(*su2));
md5sig.tcpm_keylen = keylen;
if (keylen)
memcpy(md5sig.tcpm_key, password, keylen);
sockunion_free(susock);
/*
* Handle support for MD5 signatures on prefixes, if available and
* requested. Technically the #ifdef check below is not needed because
* if prefixlen > 0 and we don't have support for this feature we would
* have already returned by now, but leaving it there to be explicit.
*/
#ifdef TCP_MD5SIG_EXT
if (prefixlen > 0) {
md5sig.tcpm_prefixlen = prefixlen;
md5sig.tcpm_flags = TCP_MD5SIG_FLAG_PREFIX;
optname = TCP_MD5SIG_EXT;
}
#endif /* TCP_MD5SIG_EXT */
#endif /* GNU_LINUX */
if ((ret = setsockopt(sock, IPPROTO_TCP, optname, &md5sig,
sizeof(md5sig)))
< 0) {
/* ENOENT is harmless. It is returned when we clear a password
for which
one was not previously set. */
if (ENOENT == errno)
ret = 0;
else
flog_err_sys(
EC_LIB_SYSTEM_CALL,
"sockopt_tcp_signature: setsockopt(%d): %s",
sock, safe_strerror(errno));
}
return ret;
#endif /* HAVE_TCP_MD5SIG */
/*
* Making compiler happy. If we get to this point we probably
* have done something really really wrong.
*/
return -2;
}
int sockopt_tcp_signature(int sock, union sockunion *su, const char *password)
{
return sockopt_tcp_signature_ext(sock, su, 0, password);
}