/*
* link_gre.c gre driver module
*
* This program 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 of the License, or (at your option) any later version.
*
* Authors: Herbert Xu <herbert@gondor.apana.org.au>
*
*/
#include <string.h>
#include <net/if.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <linux/ip.h>
#include <linux/if_tunnel.h>
#include "rt_names.h"
#include "utils.h"
#include "ip_common.h"
#include "tunnel.h"
static void usage(void) __attribute__((noreturn));
static void usage(void)
{
fprintf(stderr, "Usage: ip link { add | set | change | replace | del } NAME\n");
fprintf(stderr, " type { gre | gretap } [ remote ADDR ] [ local ADDR ]\n");
fprintf(stderr, " [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n");
fprintf(stderr, " [ ttl TTL ] [ tos TOS ] [ [no]pmtudisc ] [ dev PHYS_DEV ]\n");
fprintf(stderr, "\n");
fprintf(stderr, "Where: NAME := STRING\n");
fprintf(stderr, " ADDR := { IP_ADDRESS | any }\n");
fprintf(stderr, " TOS := { NUMBER | inherit }\n");
fprintf(stderr, " TTL := { 1..255 | inherit }\n");
fprintf(stderr, " KEY := { DOTTED_QUAD | NUMBER }\n");
exit(-1);
}
static int gre_parse_opt(struct link_util *lu, int argc, char **argv,
struct nlmsghdr *n)
{
struct {
struct nlmsghdr n;
struct ifinfomsg i;
char buf[1024];
} req;
struct ifinfomsg *ifi = (struct ifinfomsg *)(n + 1);
struct rtattr *tb[IFLA_MAX + 1];
struct rtattr *linkinfo[IFLA_INFO_MAX+1];
struct rtattr *greinfo[IFLA_GRE_MAX + 1];
__u16 iflags = 0;
__u16 oflags = 0;
unsigned ikey = 0;
unsigned okey = 0;
unsigned saddr = 0;
unsigned daddr = 0;
unsigned link = 0;
__u8 pmtudisc = 1;
__u8 ttl = 0;
__u8 tos = 0;
int len;
if (!(n->nlmsg_flags & NLM_F_CREATE)) {
memset(&req, 0, sizeof(req));
req.n.nlmsg_len = NLMSG_LENGTH(sizeof(*ifi));
req.n.nlmsg_flags = NLM_F_REQUEST;
req.n.nlmsg_type = RTM_GETLINK;
req.i.ifi_family = preferred_family;
req.i.ifi_index = ifi->ifi_index;
if (rtnl_talk(&rth, &req.n, 0, 0, &req.n) < 0) {
get_failed:
fprintf(stderr,
"Failed to get existing tunnel info.\n");
return -1;
}
len = req.n.nlmsg_len;
len -= NLMSG_LENGTH(sizeof(*ifi));
if (len < 0)
goto get_failed;
parse_rtattr(tb, IFLA_MAX, IFLA_RTA(&req.i), len);
if (!tb[IFLA_LINKINFO])
goto get_failed;
parse_rtattr_nested(linkinfo, IFLA_INFO_MAX, tb[IFLA_LINKINFO]);
if (!linkinfo[IFLA_INFO_DATA])
goto get_failed;
parse_rtattr_nested(greinfo, IFLA_GRE_MAX,
linkinfo[IFLA_INFO_DATA]);
if (greinfo[IFLA_GRE_IKEY])
ikey = rta_getattr_u32(greinfo[IFLA_GRE_IKEY]);
if (greinfo[IFLA_GRE_OKEY])
okey = rta_getattr_u32(greinfo[IFLA_GRE_OKEY]);
if (greinfo[IFLA_GRE_IFLAGS])
iflags = rta_getattr_u16(greinfo[IFLA_GRE_IFLAGS]);
if (greinfo[IFLA_GRE_OFLAGS])
oflags = rta_getattr_u16(greinfo[IFLA_GRE_OFLAGS]);
if (greinfo[IFLA_GRE_LOCAL])
saddr = rta_getattr_u32(greinfo[IFLA_GRE_LOCAL]);
if (greinfo[IFLA_GRE_REMOTE])
daddr = rta_getattr_u32(greinfo[IFLA_GRE_REMOTE]);
if (greinfo[IFLA_GRE_PMTUDISC])
pmtudisc = rta_getattr_u8(
greinfo[IFLA_GRE_PMTUDISC]);
if (greinfo[IFLA_GRE_TTL])
ttl = rta_getattr_u8(greinfo[IFLA_GRE_TTL]);
if (greinfo[IFLA_GRE_TOS])
tos = rta_getattr_u8(greinfo[IFLA_GRE_TOS]);
if (greinfo[IFLA_GRE_LINK])
link = rta_getattr_u8(greinfo[IFLA_GRE_LINK]);
}
while (argc > 0) {
if (!matches(*argv, "key")) {
unsigned uval;
NEXT_ARG();
iflags |= GRE_KEY;
oflags |= GRE_KEY;
if (strchr(*argv, '.'))
uval = get_addr32(*argv);
else {
if (get_unsigned(&uval, *argv, 0) < 0) {
fprintf(stderr,
"Invalid value for \"key\"\n");
exit(-1);
}
uval = htonl(uval);
}
ikey = okey = uval;
} else if (!matches(*argv, "ikey")) {
unsigned uval;
NEXT_ARG();
iflags |= GRE_KEY;
if (strchr(*argv, '.'))
uval = get_addr32(*argv);
else {
if (get_unsigned(&uval, *argv, 0)<0) {
fprintf(stderr, "invalid value of \"ikey\"\n");
exit(-1);
}
uval = htonl(uval);
}
ikey = uval;
} else if (!matches(*argv, "okey")) {
unsigned uval;
NEXT_ARG();
oflags |= GRE_KEY;
if (strchr(*argv, '.'))
uval = get_addr32(*argv);
else {
if (get_unsigned(&uval, *argv, 0)<0) {
fprintf(stderr, "invalid value of \"okey\"\n");
exit(-1);
}
uval = htonl(uval);
}
okey = uval;
} else if (!matches(*argv, "seq")) {
iflags |= GRE_SEQ;
oflags |= GRE_SEQ;
} else if (!matches(*argv, "iseq")) {
iflags |= GRE_SEQ;
} else if (!matches(*argv, "oseq")) {
oflags |= GRE_SEQ;
} else if (!matches(*argv, "csum")) {
iflags |= GRE_CSUM;
oflags |= GRE_CSUM;
} else if (!matches(*argv, "icsum")) {
iflags |= GRE_CSUM;
} else if (!matches(*argv, "ocsum")) {
oflags |= GRE_CSUM;
} else if (!matches(*argv, "nopmtudisc")) {
pmtudisc = 0;
} else if (!matches(*argv, "pmtudisc")) {
pmtudisc = 1;
} else if (!matches(*argv, "remote")) {
NEXT_ARG();
if (strcmp(*argv, "any"))
daddr = get_addr32(*argv);
} else if (!matches(*argv, "local")) {
NEXT_ARG();
if (strcmp(*argv, "any"))
saddr = get_addr32(*argv);
} else if (!matches(*argv, "dev")) {
NEXT_ARG();
link = if_nametoindex(*argv);
if (link == 0)
exit(-1);
} else if (!matches(*argv, "ttl") ||
!matches(*argv, "hoplimit")) {
unsigned uval;
NEXT_ARG();
if (strcmp(*argv, "inherit") != 0) {
if (get_unsigned(&uval, *argv, 0))
invarg("invalid TTL\n", *argv);
if (uval > 255)
invarg("TTL must be <= 255\n", *argv);
ttl = uval;
}
} else if (!matches(*argv, "tos") ||
!matches(*argv, "tclass") ||
!matches(*argv, "dsfield")) {
__u32 uval;
NEXT_ARG();
if (strcmp(*argv, "inherit") != 0) {
if (rtnl_dsfield_a2n(&uval, *argv))
invarg("bad TOS value", *argv);
tos = uval;
} else
tos = 1;
} else
usage();
argc--; argv++;
}
if (!ikey && IN_MULTICAST(ntohl(daddr))) {
ikey = daddr;
iflags |= GRE_KEY;
}
if (!okey && IN_MULTICAST(ntohl(daddr))) {
okey = daddr;
oflags |= GRE_KEY;
}
if (IN_MULTICAST(ntohl(daddr)) && !saddr) {
fprintf(stderr, "Broadcast tunnel requires a source address.\n");
return -1;
}
addattr32(n, 1024, IFLA_GRE_IKEY, ikey);
addattr32(n, 1024, IFLA_GRE_OKEY, okey);
addattr_l(n, 1024, IFLA_GRE_IFLAGS, &iflags, 2);
addattr_l(n, 1024, IFLA_GRE_OFLAGS, &oflags, 2);
addattr_l(n, 1024, IFLA_GRE_LOCAL, &saddr, 4);
addattr_l(n, 1024, IFLA_GRE_REMOTE, &daddr, 4);
addattr_l(n, 1024, IFLA_GRE_PMTUDISC, &pmtudisc, 1);
if (link)
addattr32(n, 1024, IFLA_GRE_LINK, link);
addattr_l(n, 1024, IFLA_GRE_TTL, &ttl, 1);
addattr_l(n, 1024, IFLA_GRE_TOS, &tos, 1);
return 0;
}
static void gre_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
{
char s1[1024];
char s2[64];
const char *local = "any";
const char *remote = "any";
unsigned iflags = 0;
unsigned oflags = 0;
if (!tb)
return;
if (tb[IFLA_GRE_REMOTE]) {
unsigned addr = rta_getattr_u32(tb[IFLA_GRE_REMOTE]);
if (addr)
remote = format_host(AF_INET, 4, &addr, s1, sizeof(s1));
}
fprintf(f, "remote %s ", remote);
if (tb[IFLA_GRE_LOCAL]) {
unsigned addr = rta_getattr_u32(tb[IFLA_GRE_LOCAL]);
if (addr)
local = format_host(AF_INET, 4, &addr, s1, sizeof(s1));
}
fprintf(f, "local %s ", local);
if (tb[IFLA_GRE_LINK] && rta_getattr_u32(tb[IFLA_GRE_LINK])) {
unsigned link = rta_getattr_u32(tb[IFLA_GRE_LINK]);
const char *n = if_indextoname(link, s2);
if (n)
fprintf(f, "dev %s ", n);
else
fprintf(f, "dev %u ", link);
}
if (tb[IFLA_GRE_TTL] && rta_getattr_u8(tb[IFLA_GRE_TTL]))
fprintf(f, "ttl %d ", rta_getattr_u8(tb[IFLA_GRE_TTL]));
else
fprintf(f, "ttl inherit ");
if (tb[IFLA_GRE_TOS] && rta_getattr_u8(tb[IFLA_GRE_TOS])) {
int tos = rta_getattr_u8(tb[IFLA_GRE_TOS]);
fputs("tos ", f);
if (tos == 1)
fputs("inherit ", f);
else
fprintf(f, "0x%x ", tos);
}
if (tb[IFLA_GRE_PMTUDISC] &&
!rta_getattr_u8(tb[IFLA_GRE_PMTUDISC]))
fputs("nopmtudisc ", f);
if (tb[IFLA_GRE_IFLAGS])
iflags = rta_getattr_u16(tb[IFLA_GRE_IFLAGS]);
if (tb[IFLA_GRE_OFLAGS])
oflags = rta_getattr_u16(tb[IFLA_GRE_OFLAGS]);
if ((iflags & GRE_KEY) && tb[IFLA_GRE_IKEY]) {
inet_ntop(AF_INET, RTA_DATA(tb[IFLA_GRE_IKEY]), s2, sizeof(s2));
fprintf(f, "ikey %s ", s2);
}
if ((oflags & GRE_KEY) && tb[IFLA_GRE_OKEY]) {
inet_ntop(AF_INET, RTA_DATA(tb[IFLA_GRE_OKEY]), s2, sizeof(s2));
fprintf(f, "okey %s ", s2);
}
if (iflags & GRE_SEQ)
fputs("iseq ", f);
if (oflags & GRE_SEQ)
fputs("oseq ", f);
if (iflags & GRE_CSUM)
fputs("icsum ", f);
if (oflags & GRE_CSUM)
fputs("ocsum ", f);
}
struct link_util gre_link_util = {
.id = "gre",
.maxattr = IFLA_GRE_MAX,
.parse_opt = gre_parse_opt,
.print_opt = gre_print_opt,
};
struct link_util gretap_link_util = {
.id = "gretap",
.maxattr = IFLA_GRE_MAX,
.parse_opt = gre_parse_opt,
.print_opt = gre_print_opt,
};