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/*
* BIRD Internet Routing Daemon -- Linux Multicasting and Network Includes
*
* (c) 1998--2000 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef IPV6_MINHOPCOUNT
#define IPV6_MINHOPCOUNT 73
#endif
#ifndef TCP_MD5SIG_EXT
#define TCP_MD5SIG_EXT 32
#endif
#ifndef TCP_MD5SIG_FLAG_PREFIX
#define TCP_MD5SIG_FLAG_PREFIX 1
#endif
/* We redefine the tcp_md5sig structure with different name to avoid collision with older headers */
struct tcp_md5sig_ext {
struct sockaddr_storage tcpm_addr; /* Address associated */
u8 tcpm_flags; /* Extension flags */
u8 tcpm_prefixlen; /* Address prefix */
u16 tcpm_keylen; /* Key length */
u32 __tcpm_pad2; /* Zero */
u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN]; /* Key (binary) */
};
/* Linux does not care if sa_len is larger than needed */
#define SA_LEN(x) sizeof(sockaddr)
/*
* Linux IPv4 multicast syscalls
*/
#define INIT_MREQ4(maddr,ifa) \
{ .imr_multiaddr = ipa_to_in4(maddr), .imr_ifindex = ifa->index }
static inline int
sk_setup_multicast4(sock *s)
{
struct ip_mreqn mr = { .imr_ifindex = s->iface->index };
int ttl = s->ttl;
int n = 0;
/* This defines where should we send _outgoing_ multicasts */
if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_IF, &mr, sizeof(mr)) < 0)
ERR("IP_MULTICAST_IF");
if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
ERR("IP_MULTICAST_TTL");
if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_LOOP, &n, sizeof(n)) < 0)
ERR("IP_MULTICAST_LOOP");
return 0;
}
static inline int
sk_join_group4(sock *s, ip_addr maddr)
{
struct ip_mreqn mr = INIT_MREQ4(maddr, s->iface);
if (setsockopt(s->fd, SOL_IP, IP_ADD_MEMBERSHIP, &mr, sizeof(mr)) < 0)
ERR("IP_ADD_MEMBERSHIP");
return 0;
}
static inline int
sk_leave_group4(sock *s, ip_addr maddr)
{
struct ip_mreqn mr = INIT_MREQ4(maddr, s->iface);
if (setsockopt(s->fd, SOL_IP, IP_DROP_MEMBERSHIP, &mr, sizeof(mr)) < 0)
ERR("IP_DROP_MEMBERSHIP");
return 0;
}
/*
* Linux IPv4 packet control messages
*/
/* Mostly similar to standardized IPv6 code */
#define CMSG4_SPACE_PKTINFO CMSG_SPACE(sizeof(struct in_pktinfo))
#define CMSG4_SPACE_TTL CMSG_SPACE(sizeof(int))
static inline int
sk_request_cmsg4_pktinfo(sock *s)
{
int y = 1;
if (setsockopt(s->fd, SOL_IP, IP_PKTINFO, &y, sizeof(y)) < 0)
ERR("IP_PKTINFO");
return 0;
}
static inline int
sk_request_cmsg4_ttl(sock *s)
{
int y = 1;
if (setsockopt(s->fd, SOL_IP, IP_RECVTTL, &y, sizeof(y)) < 0)
ERR("IP_RECVTTL");
return 0;
}
static inline void
sk_process_cmsg4_pktinfo(sock *s, struct cmsghdr *cm)
{
if (cm->cmsg_type == IP_PKTINFO)
{
struct in_pktinfo *pi = (struct in_pktinfo *) CMSG_DATA(cm);
s->laddr = ipa_from_in4(pi->ipi_addr);
s->lifindex = pi->ipi_ifindex;
}
}
static inline void
sk_process_cmsg4_ttl(sock *s, struct cmsghdr *cm)
{
if (cm->cmsg_type == IP_TTL)
s->rcv_ttl = * (int *) CMSG_DATA(cm);
}
static inline void
sk_prepare_cmsgs4(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
{
struct cmsghdr *cm;
struct in_pktinfo *pi;
int controllen = 0;
msg->msg_control = cbuf;
msg->msg_controllen = cbuflen;
cm = CMSG_FIRSTHDR(msg);
cm->cmsg_level = SOL_IP;
cm->cmsg_type = IP_PKTINFO;
cm->cmsg_len = CMSG_LEN(sizeof(*pi));
controllen += CMSG_SPACE(sizeof(*pi));
pi = (struct in_pktinfo *) CMSG_DATA(cm);
pi->ipi_ifindex = s->iface ? s->iface->index : 0;
pi->ipi_spec_dst = ipa_to_in4(s->saddr);
pi->ipi_addr = ipa_to_in4(IPA_NONE);
msg->msg_controllen = controllen;
}
/*
* Miscellaneous Linux socket syscalls
*/
int
sk_set_md5_auth(sock *s, ip_addr local UNUSED, ip_addr remote, int pxlen, struct iface *ifa, char *passwd, int setkey UNUSED)
{
struct tcp_md5sig_ext md5;
memset(&md5, 0, sizeof(md5));
sockaddr_fill((sockaddr *) &md5.tcpm_addr, s->af, remote, ifa, 0);
if (passwd)
{
int len = strlen(passwd);
if (len > TCP_MD5SIG_MAXKEYLEN)
ERR_MSG("The password for TCP MD5 Signature is too long");
md5.tcpm_keylen = len;
memcpy(&md5.tcpm_key, passwd, len);
}
if (pxlen < 0)
{
if (setsockopt(s->fd, SOL_TCP, TCP_MD5SIG, &md5, sizeof(md5)) < 0)
if (errno == ENOPROTOOPT)
ERR_MSG("Kernel does not support TCP MD5 signatures");
else
ERR("TCP_MD5SIG");
}
else
{
md5.tcpm_flags = TCP_MD5SIG_FLAG_PREFIX;
md5.tcpm_prefixlen = pxlen;
if (setsockopt(s->fd, SOL_TCP, TCP_MD5SIG_EXT, &md5, sizeof(md5)) < 0)
{
if (errno == ENOPROTOOPT)
ERR_MSG("Kernel does not support extended TCP MD5 signatures");
else
ERR("TCP_MD5SIG_EXT");
}
}
return 0;
}
static inline int
sk_set_min_ttl4(sock *s, int ttl)
{
if (setsockopt(s->fd, SOL_IP, IP_MINTTL, &ttl, sizeof(ttl)) < 0)
{
if (errno == ENOPROTOOPT)
ERR_MSG("Kernel does not support IPv4 TTL security");
else
ERR("IP_MINTTL");
}
return 0;
}
static inline int
sk_set_min_ttl6(sock *s, int ttl)
{
if (setsockopt(s->fd, SOL_IPV6, IPV6_MINHOPCOUNT, &ttl, sizeof(ttl)) < 0)
{
if (errno == ENOPROTOOPT)
ERR_MSG("Kernel does not support IPv6 TTL security");
else
ERR("IPV6_MINHOPCOUNT");
}
return 0;
}
static inline int
sk_disable_mtu_disc4(sock *s)
{
int dont = IP_PMTUDISC_DONT;
if (setsockopt(s->fd, SOL_IP, IP_MTU_DISCOVER, &dont, sizeof(dont)) < 0)
ERR("IP_MTU_DISCOVER");
return 0;
}
static inline int
sk_disable_mtu_disc6(sock *s)
{
int dont = IPV6_PMTUDISC_DONT;
if (setsockopt(s->fd, SOL_IPV6, IPV6_MTU_DISCOVER, &dont, sizeof(dont)) < 0)
ERR("IPV6_MTU_DISCOVER");
return 0;
}
int sk_priority_control = 7;
static inline int
sk_set_priority(sock *s, int prio)
{
if (setsockopt(s->fd, SOL_SOCKET, SO_PRIORITY, &prio, sizeof(prio)) < 0)
ERR("SO_PRIORITY");
return 0;
}
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