miniupnp/minissdpd/ifacewatch.c

322 lines
8.9 KiB
C

/* $Id: ifacewatch.c,v 1.13 2012/05/21 17:13:11 nanard Exp $ */
/* MiniUPnP project
* (c) 2011-2012 Thomas Bernard
* website : http://miniupnp.free.fr/ or http://miniupnp.tuxfamily.org/
* This software is subject to the conditions detailed
* in the LICENCE file provided within the distribution */
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <net/if.h>
#ifdef __linux__
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#else /* __linux__ */
#include <net/route.h>
#ifdef AF_LINK
#include <net/if_dl.h>
#endif
#endif /* __linux__ */
#include <syslog.h>
#include "openssdpsocket.h"
#include "upnputils.h"
#ifndef __linux__
#if defined(__OpenBSD__) || defined(__FreeBSD__)
#define SALIGN (sizeof(long) - 1)
#else
#define SALIGN (sizeof(int32_t) - 1)
#endif
#define SA_RLEN(sa) ((sa)->sa_len ? (((sa)->sa_len + SALIGN) & ~SALIGN) : (SALIGN + 1))
#endif
int
OpenAndConfInterfaceWatchSocket(void)
{
int s;
#ifdef __linux__
struct sockaddr_nl addr;
s = socket(PF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
#else /* __linux__*/
/*s = socket(PF_ROUTE, SOCK_RAW, AF_INET);*/
s = socket(PF_ROUTE, SOCK_RAW, AF_UNSPEC);
/* The family parameter may be AF_UNSPEC which will provide routing informa-
* tion for all address families, or can be restricted to a specific address
* family by specifying which one is desired. There can be more than one
* routing socket open per system. */
#endif
if(s < 0) {
syslog(LOG_ERR, "%s socket: %m",
"OpenAndConfInterfaceWatchSocket");
return -1;
}
if(!set_non_blocking(s)) {
syslog(LOG_WARNING, "%s failed to set socket non blocking : %m",
"OpenAndConfInterfaceWatchSocket");
}
#ifdef __linux__
memset(&addr, 0, sizeof(addr));
addr.nl_family = AF_NETLINK;
addr.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR | RTMGRP_IPV6_IFADDR;
if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
syslog(LOG_ERR, "bind(netlink): %m");
close(s);
return -1;
}
#endif
return s;
}
/**
* Process the message and add/drop multicast membership if needed
*/
int
ProcessInterfaceWatch(int s, int s_ssdp, int s_ssdp6,
int n_if_addr, const char * * if_addr)
{
ssize_t len;
int i;
char buffer[4096];
#ifdef __linux__
struct iovec iov;
struct msghdr hdr;
struct nlmsghdr *nlhdr;
struct ifaddrmsg *ifa;
struct rtattr *rta;
int ifa_len;
iov.iov_base = buffer;
iov.iov_len = sizeof(buffer);
memset(&hdr, 0, sizeof(hdr));
hdr.msg_iov = &iov;
hdr.msg_iovlen = 1;
len = recvmsg(s, &hdr, 0);
if(len < 0) {
syslog(LOG_ERR, "recvmsg(s, &hdr, 0): %m");
return -1;
}
for(nlhdr = (struct nlmsghdr *)buffer;
NLMSG_OK(nlhdr, len);
nlhdr = NLMSG_NEXT(nlhdr, len)) {
int is_del = 0;
char address[48];
char ifname[IFNAMSIZ];
address[0] = '\0';
ifname[0] = '\0';
if(nlhdr->nlmsg_type == NLMSG_DONE)
break;
switch(nlhdr->nlmsg_type) {
/* case RTM_NEWLINK: */
/* case RTM_DELLINK: */
case RTM_DELADDR:
is_del = 1;
case RTM_NEWADDR:
/* http://linux-hacks.blogspot.fr/2009/01/sample-code-to-learn-netlink.html */
ifa = (struct ifaddrmsg *)NLMSG_DATA(nlhdr);
rta = (struct rtattr *)IFA_RTA(ifa);
ifa_len = IFA_PAYLOAD(nlhdr);
syslog(LOG_DEBUG, "%s %s index=%d fam=%d prefixlen=%d flags=%d scope=%d",
"ProcessInterfaceWatchNotify", is_del ? "RTM_DELADDR" : "RTM_NEWADDR",
ifa->ifa_index, ifa->ifa_family, ifa->ifa_prefixlen,
ifa->ifa_flags, ifa->ifa_scope);
for(;RTA_OK(rta, ifa_len); rta = RTA_NEXT(rta, ifa_len)) {
/*RTA_DATA(rta)*/
/*rta_type : IFA_ADDRESS, IFA_LOCAL, etc. */
char tmp[128];
memset(tmp, 0, sizeof(tmp));
switch(rta->rta_type) {
case IFA_ADDRESS:
case IFA_LOCAL:
case IFA_BROADCAST:
case IFA_ANYCAST:
inet_ntop(ifa->ifa_family, RTA_DATA(rta), tmp, sizeof(tmp));
if(rta->rta_type == IFA_ADDRESS)
strncpy(address, tmp, sizeof(address));
break;
case IFA_LABEL:
strncpy(tmp, RTA_DATA(rta), sizeof(tmp));
strncpy(ifname, tmp, sizeof(ifname));
break;
case IFA_CACHEINFO:
{
struct ifa_cacheinfo *cache_info;
cache_info = RTA_DATA(rta);
snprintf(tmp, sizeof(tmp), "valid=%u prefered=%u",
cache_info->ifa_valid, cache_info->ifa_prefered);
}
break;
default:
strncpy(tmp, "*unknown*", sizeof(tmp));
}
syslog(LOG_DEBUG, " rta_len=%d rta_type=%d '%s'", rta->rta_len, rta->rta_type, tmp);
}
syslog(LOG_INFO, "%s: %s/%d %s",
is_del ? "RTM_DELADDR" : "RTM_NEWADDR",
address, ifa->ifa_prefixlen, ifname);
for(i = 0; i < n_if_addr; i++) {
if((0 == strcmp(address, if_addr[i])) ||
(0 == strcmp(ifname, if_addr[i])) ||
(ifa->ifa_index == if_nametoindex(if_addr[i]))) {
if(ifa->ifa_family == AF_INET && address[0] != '\0')
AddDropMulticastMembership(s_ssdp, address, 0, is_del);
else if(ifa->ifa_family == AF_INET6)
AddDropMulticastMembership(s_ssdp6, if_addr[i], 1, is_del);
break;
}
}
break;
default:
syslog(LOG_DEBUG, "unknown nlmsg_type=%d", nlhdr->nlmsg_type);
}
}
#else /* __linux__ */
struct rt_msghdr * rtm;
struct ifa_msghdr * ifam;
int is_del = 0;
char tmp[64];
char * p;
struct sockaddr * sa;
int addr;
char address[48];
char ifname[IFNAMSIZ];
int family = AF_UNSPEC;
int prefixlen = 0;
address[0] = '\0';
ifname[0] = '\0';
len = recv(s, buffer, sizeof(buffer), 0);
if(len < 0) {
syslog(LOG_ERR, "%s recv: %m", "ProcessInterfaceWatchNotify");
return -1;
}
rtm = (struct rt_msghdr *)buffer;
switch(rtm->rtm_type) {
case RTM_DELADDR:
is_del = 1;
case RTM_NEWADDR:
ifam = (struct ifa_msghdr *)buffer;
syslog(LOG_DEBUG, "%s %s len=%d/%hu index=%hu addrs=%x flags=%x",
"ProcessInterfaceWatchNotify", is_del?"RTM_DELADDR":"RTM_NEWADDR",
(int)len, ifam->ifam_msglen,
ifam->ifam_index, ifam->ifam_addrs, ifam->ifam_flags);
p = buffer + sizeof(struct ifa_msghdr);
addr = 1;
while(p < buffer + len) {
sa = (struct sockaddr *)p;
while(!(addr & ifam->ifam_addrs) && (addr <= ifam->ifam_addrs))
addr = addr << 1;
sockaddr_to_string(sa, tmp, sizeof(tmp));
syslog(LOG_DEBUG, " %s", tmp);
switch(addr) {
case RTA_DST:
case RTA_GATEWAY:
break;
case RTA_NETMASK:
if(sa->sa_family == AF_INET
#if defined(__OpenBSD__)
|| (sa->sa_family == 0 &&
sa->sa_len <= sizeof(struct sockaddr_in))
#endif
) {
uint32_t sin_addr = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
while((prefixlen < 32) &&
((sin_addr & (1 << (31 - prefixlen))) != 0))
prefixlen++;
} else if(sa->sa_family == AF_INET6
#if defined(__OpenBSD__)
|| (sa->sa_family == 0 &&
sa->sa_len == sizeof(struct sockaddr_in6))
#endif
) {
int i = 0;
uint8_t * q = ((struct sockaddr_in6 *)sa)->sin6_addr.s6_addr;
while((*q == 0xff) && (i < 16)) {
prefixlen += 8;
q++; i++;
}
if(i < 16) {
i = 0;
while((i < 8) &&
((*q & (1 << (7 - i))) != 0))
i++;
prefixlen += i;
}
}
break;
case RTA_GENMASK:
break;
case RTA_IFP:
#ifdef AF_LINK
if(sa->sa_family == AF_LINK) {
struct sockaddr_dl * sdl = (struct sockaddr_dl *)sa;
memset(ifname, 0, sizeof(ifname));
memcpy(ifname, sdl->sdl_data, sdl->sdl_nlen);
}
#endif
break;
case RTA_IFA:
family = sa->sa_family;
if(sa->sa_family == AF_INET) {
inet_ntop(sa->sa_family,
&((struct sockaddr_in *)sa)->sin_addr,
address, sizeof(address));
} else if(sa->sa_family == AF_INET6) {
inet_ntop(sa->sa_family,
&((struct sockaddr_in6 *)sa)->sin6_addr,
address, sizeof(address));
}
break;
case RTA_AUTHOR:
break;
case RTA_BRD:
break;
}
#if 0
syslog(LOG_DEBUG, " %d.%d.%d.%d %02x%02x%02x%02x",
(uint8_t)p[0], (uint8_t)p[1], (uint8_t)p[2], (uint8_t)p[3],
(uint8_t)p[0], (uint8_t)p[1], (uint8_t)p[2], (uint8_t)p[3]);
syslog(LOG_DEBUG, " %d.%d.%d.%d %02x%02x%02x%02x",
(uint8_t)p[4], (uint8_t)p[5], (uint8_t)p[6], (uint8_t)p[7],
(uint8_t)p[4], (uint8_t)p[5], (uint8_t)p[6], (uint8_t)p[7]);
#endif
p += SA_RLEN(sa);
addr = addr << 1;
}
syslog(LOG_INFO, "%s: %s/%d %s",
is_del ? "RTM_DELADDR" : "RTM_NEWADDR",
address, prefixlen, ifname);
for(i = 0; i < n_if_addr; i++) {
if(0 == strcmp(address, if_addr[i]) ||
0 == strcmp(ifname, if_addr[i]) ||
ifam->ifam_index == if_nametoindex(if_addr[i])) {
if(family == AF_INET && address[0] != '\0')
AddDropMulticastMembership(s_ssdp, address, 0, is_del);
else if(family == AF_INET6)
AddDropMulticastMembership(s_ssdp6, if_addr[i], 1, is_del);
break;
}
}
break;
default:
syslog(LOG_DEBUG, "Unknown RTM message : rtm->rtm_type=%d len=%d",
rtm->rtm_type, (int)len);
}
#endif
return 0;
}