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Correct behaviour for TCP queries to allowed address via banned interface.

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This commit is contained in:
Simon Kelley
2013-01-22 13:53:04 +00:00
parent 30393100c1
commit 22ce550e53
4 changed files with 125 additions and 20 deletions
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71
src/network.c
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@@ -459,6 +459,77 @@ int set_ipv6pktinfo(int fd)
return 0;
}
#endif
/* Find the interface on which a TCP connection arrived, if possible, or zero otherwise. */
int tcp_interface(int fd, int af)
{
int if_index = 0;
#ifdef HAVE_LINUX_NETWORK
int opt = 1;
struct cmsghdr *cmptr;
struct msghdr msg;
/* use mshdr do that the CMSDG_* macros are available */
msg.msg_control = daemon->packet;
msg.msg_controllen = daemon->packet_buff_sz;
/* we overwrote the buffer... */
daemon->srv_save = NULL;
if (af == AF_INET)
{
if (setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &opt, sizeof(opt)) != -1 &&
getsockopt(fd, IPPROTO_IP, IP_PKTOPTIONS, msg.msg_control, (socklen_t *)&msg.msg_controllen) != -1)
for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
if (cmptr->cmsg_level == IPPROTO_IP && cmptr->cmsg_type == IP_PKTINFO)
{
union {
unsigned char *c;
struct in_pktinfo *p;
} p;
p.c = CMSG_DATA(cmptr);
if_index = p.p->ipi_ifindex;
}
}
#ifdef HAVE_IPV6
else
{
/* Only the RFC-2292 API has the ability to find the interface for TCP connections,
it was removed in RFC-3542 !!!!
Fortunately, Linux kept the 2292 ABI when it moved to 3542. The following code always
uses the old ABI, and should work with pre- and post-3542 kernel headers */
#ifdef IPV6_2292PKTOPTIONS
# define PKTOPTIONS IPV6_2292PKTOPTIONS
#else
# define PKTOPTIONS IPV6_PKTOPTIONS
#endif
if (set_ipv6pktinfo(fd) &&
getsockopt(fd, IPPROTO_IPV6, PKTOPTIONS, msg.msg_control, (socklen_t *)&msg.msg_controllen) != -1)
{
for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
if (cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == daemon->v6pktinfo)
{
union {
unsigned char *c;
struct in6_pktinfo *p;
} p;
p.c = CMSG_DATA(cmptr);
if_index = p.p->ipi6_ifindex;
}
}
}
#endif /* IPV6 */
#endif /* Linux */
return if_index;
}
static struct listener *create_listeners(union mysockaddr *addr, int do_tftp, int dienow)
{