/*
* iptunnel.c "ip tunnel"
*
* 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: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <net/if_arp.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 tunnel { add | change | del | show | prl | 6rd } [ NAME ]\n"
" [ mode { ipip | gre | sit | isatap | vti } ] [ remote ADDR ] [ local ADDR ]\n"
" [ [i|o]seq ] [ [i|o]key KEY ] [ [i|o]csum ]\n"
" [ prl-default ADDR ] [ prl-nodefault ADDR ] [ prl-delete ADDR ]\n"
" [ 6rd-prefix ADDR ] [ 6rd-relay_prefix ADDR ] [ 6rd-reset ]\n"
" [ ttl TTL ] [ tos TOS ] [ [no]pmtudisc ] [ dev PHYS_DEV ]\n"
"\n"
"Where: NAME := STRING\n"
" ADDR := { IP_ADDRESS | any }\n"
" TOS := { STRING | 00..ff | inherit | inherit/STRING | inherit/00..ff }\n"
" TTL := { 1..255 | inherit }\n"
" KEY := { DOTTED_QUAD | NUMBER }\n");
exit(-1);
}
static void set_tunnel_proto(struct ip_tunnel_parm *p, int proto)
{
if (p->iph.protocol && p->iph.protocol != proto) {
fprintf(stderr,
"You managed to ask for more than one tunnel mode.\n");
exit(-1);
}
p->iph.protocol = proto;
}
static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
{
int count = 0;
const char *medium = NULL;
int isatap = 0;
memset(p, 0, sizeof(*p));
p->iph.version = 4;
p->iph.ihl = 5;
#ifndef IP_DF
#define IP_DF 0x4000 /* Flag: "Don't Fragment" */
#endif
p->iph.frag_off = htons(IP_DF);
while (argc > 0) {
if (strcmp(*argv, "mode") == 0) {
NEXT_ARG();
if (strcmp(*argv, "ipip") == 0 ||
strcmp(*argv, "ip/ip") == 0) {
set_tunnel_proto(p, IPPROTO_IPIP);
} else if (strcmp(*argv, "gre") == 0 ||
strcmp(*argv, "gre/ip") == 0) {
set_tunnel_proto(p, IPPROTO_GRE);
} else if (strcmp(*argv, "sit") == 0 ||
strcmp(*argv, "ipv6/ip") == 0) {
set_tunnel_proto(p, IPPROTO_IPV6);
} else if (strcmp(*argv, "isatap") == 0) {
set_tunnel_proto(p, IPPROTO_IPV6);
isatap++;
} else if (strcmp(*argv, "vti") == 0) {
set_tunnel_proto(p, IPPROTO_IPIP);
p->i_flags |= VTI_ISVTI;
} else {
fprintf(stderr,
"Unknown tunnel mode \"%s\"\n", *argv);
exit(-1);
}
} else if (strcmp(*argv, "key") == 0) {
NEXT_ARG();
p->i_flags |= GRE_KEY;
p->o_flags |= GRE_KEY;
p->i_key = p->o_key = tnl_parse_key("key", *argv);
} else if (strcmp(*argv, "ikey") == 0) {
NEXT_ARG();
p->i_flags |= GRE_KEY;
p->i_key = tnl_parse_key("ikey", *argv);
} else if (strcmp(*argv, "okey") == 0) {
NEXT_ARG();
p->o_flags |= GRE_KEY;
p->o_key = tnl_parse_key("okey", *argv);
} else if (strcmp(*argv, "seq") == 0) {
p->i_flags |= GRE_SEQ;
p->o_flags |= GRE_SEQ;
} else if (strcmp(*argv, "iseq") == 0) {
p->i_flags |= GRE_SEQ;
} else if (strcmp(*argv, "oseq") == 0) {
p->o_flags |= GRE_SEQ;
} else if (strcmp(*argv, "csum") == 0) {
p->i_flags |= GRE_CSUM;
p->o_flags |= GRE_CSUM;
} else if (strcmp(*argv, "icsum") == 0) {
p->i_flags |= GRE_CSUM;
} else if (strcmp(*argv, "ocsum") == 0) {
p->o_flags |= GRE_CSUM;
} else if (strcmp(*argv, "nopmtudisc") == 0) {
p->iph.frag_off = 0;
} else if (strcmp(*argv, "pmtudisc") == 0) {
p->iph.frag_off = htons(IP_DF);
} else if (strcmp(*argv, "remote") == 0) {
NEXT_ARG();
p->iph.daddr = get_addr32(*argv);
} else if (strcmp(*argv, "local") == 0) {
NEXT_ARG();
p->iph.saddr = get_addr32(*argv);
} else if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
medium = *argv;
} else if (strcmp(*argv, "ttl") == 0 ||
strcmp(*argv, "hoplimit") == 0 ||
strcmp(*argv, "hlim") == 0) {
__u8 uval;
NEXT_ARG();
if (strcmp(*argv, "inherit") != 0) {
if (get_u8(&uval, *argv, 0))
invarg("invalid TTL\n", *argv);
p->iph.ttl = uval;
}
} else if (strcmp(*argv, "tos") == 0 ||
strcmp(*argv, "tclass") == 0 ||
matches(*argv, "dsfield") == 0) {
char *dsfield;
__u32 uval;
NEXT_ARG();
dsfield = *argv;
strsep(&dsfield, "/");
if (strcmp(*argv, "inherit") != 0) {
dsfield = *argv;
p->iph.tos = 0;
} else
p->iph.tos = 1;
if (dsfield) {
if (rtnl_dsfield_a2n(&uval, dsfield))
invarg("bad TOS value", *argv);
p->iph.tos |= uval;
}
} else {
if (strcmp(*argv, "name") == 0)
NEXT_ARG();
else if (matches(*argv, "help") == 0)
usage();
if (p->name[0])
duparg2("name", *argv);
if (get_ifname(p->name, *argv))
invarg("\"name\" not a valid ifname", *argv);
if (cmd == SIOCCHGTUNNEL && count == 0) {
struct ip_tunnel_parm old_p = {};
if (tnl_get_ioctl(*argv, &old_p))
return -1;
*p = old_p;
}
}
count++;
argc--; argv++;
}
if (p->iph.protocol == 0) {
if (memcmp(p->name, "gre", 3) == 0)
p->iph.protocol = IPPROTO_GRE;
else if (memcmp(p->name, "ipip", 4) == 0)
p->iph.protocol = IPPROTO_IPIP;
else if (memcmp(p->name, "sit", 3) == 0)
p->iph.protocol = IPPROTO_IPV6;
else if (memcmp(p->name, "isatap", 6) == 0) {
p->iph.protocol = IPPROTO_IPV6;
isatap++;
} else if (memcmp(p->name, "vti", 3) == 0) {
p->iph.protocol = IPPROTO_IPIP;
p->i_flags |= VTI_ISVTI;
}
}
if ((p->i_flags & GRE_KEY) || (p->o_flags & GRE_KEY)) {
if (!(p->i_flags & VTI_ISVTI) &&
(p->iph.protocol != IPPROTO_GRE)) {
fprintf(stderr, "Keys are not allowed with ipip and sit tunnels\n");
return -1;
}
}
if (medium) {
p->link = ll_name_to_index(medium);
if (!p->link)
return nodev(medium);
}
if (p->i_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
p->i_key = p->iph.daddr;
p->i_flags |= GRE_KEY;
}
if (p->o_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
p->o_key = p->iph.daddr;
p->o_flags |= GRE_KEY;
}
if (IN_MULTICAST(ntohl(p->iph.daddr)) && !p->iph.saddr) {
fprintf(stderr, "A broadcast tunnel requires a source address\n");
return -1;
}
if (isatap)
p->i_flags |= SIT_ISATAP;
return 0;
}
static const char *tnl_defname(const struct ip_tunnel_parm *p)
{
switch (p->iph.protocol) {
case IPPROTO_IPIP:
if (p->i_flags & VTI_ISVTI)
return "ip_vti0";
else
return "tunl0";
case IPPROTO_GRE:
return "gre0";
case IPPROTO_IPV6:
return "sit0";
}
return NULL;
}
static int do_add(int cmd, int argc, char **argv)
{
struct ip_tunnel_parm p;
const char *basedev;
if (parse_args(argc, argv, cmd, &p) < 0)
return -1;
if (p.iph.ttl && p.iph.frag_off == 0) {
fprintf(stderr, "ttl != 0 and nopmtudisc are incompatible\n");
return -1;
}
basedev = tnl_defname(&p);
if (!basedev) {
fprintf(stderr,
"cannot determine tunnel mode (ipip, gre, vti or sit)\n");
return -1;
}
return tnl_add_ioctl(cmd, basedev, p.name, &p);
}
static int do_del(int argc, char **argv)
{
struct ip_tunnel_parm p;
if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0)
return -1;
return tnl_del_ioctl(tnl_defname(&p) ? : p.name, p.name, &p);
}
static void print_tunnel(const void *t)
{
const struct ip_tunnel_parm *p = t;
struct ip_tunnel_6rd ip6rd = {};
SPRINT_BUF(b1);
/* Do not use format_host() for local addr,
* symbolic name will not be useful.
*/
open_json_object(NULL);
print_color_string(PRINT_ANY, COLOR_IFNAME, "ifname", "%s: ", p->name);
snprintf(b1, sizeof(b1), "%s/ip", tnl_strproto(p->iph.protocol));
print_string(PRINT_ANY, "mode", "%s ", b1);
print_null(PRINT_FP, NULL, "remote ", NULL);
print_color_string(PRINT_ANY, COLOR_INET, "remote", "%s ",
p->iph.daddr || is_json_context()
? format_host_r(AF_INET, 4, &p->iph.daddr, b1, sizeof(b1))
: "any");
print_null(PRINT_FP, NULL, "local ", NULL);
print_color_string(PRINT_ANY, COLOR_INET, "local", "%s",
p->iph.saddr || is_json_context()
? rt_addr_n2a_r(AF_INET, 4, &p->iph.saddr, b1, sizeof(b1))
: "any");
if (p->iph.protocol == IPPROTO_IPV6 && (p->i_flags & SIT_ISATAP)) {
struct ip_tunnel_prl prl[16] = {};
int i;
prl[0].datalen = sizeof(prl) - sizeof(prl[0]);
prl[0].addr = htonl(INADDR_ANY);
if (!tnl_prl_ioctl(SIOCGETPRL, p->name, prl)) {
for (i = 1; i < ARRAY_SIZE(prl); i++) {
if (prl[i].addr == htonl(INADDR_ANY))
continue;
if (prl[i].flags & PRL_DEFAULT)
print_string(PRINT_ANY, "pdr",
" pdr %s",
format_host(AF_INET, 4, &prl[i].addr));
else
print_string(PRINT_ANY, "pr", " pr %s",
format_host(AF_INET, 4, &prl[i].addr));
}
}
}
if (p->link) {
const char *n = ll_index_to_name(p->link);
if (n)
print_string(PRINT_ANY, "dev", " dev %s", n);
}
if (p->iph.ttl)
print_uint(PRINT_ANY, "ttl", " ttl %u", p->iph.ttl);
else
print_string(PRINT_FP, "ttl", " ttl %s", "inherit");
if (p->iph.tos) {
SPRINT_BUF(b2);
if (p->iph.tos != 1) {
if (!is_json_context() && p->iph.tos & 1)
snprintf(b2, sizeof(b2), "%s%s",
p->iph.tos & 1 ? "inherit/" : "",
rtnl_dsfield_n2a(p->iph.tos & ~1, b1, sizeof(b1)));
else
snprintf(b2, sizeof(b2), "%s",
rtnl_dsfield_n2a(p->iph.tos, b1, sizeof(b1)));
print_string(PRINT_ANY, "tos", " tos %s", b2);
} else {
print_string(PRINT_FP, NULL, " tos %s", "inherit");
}
}
if (!(p->iph.frag_off & htons(IP_DF)))
print_null(PRINT_ANY, "nopmtudisc", " nopmtudisc", NULL);
if (p->iph.protocol == IPPROTO_IPV6 && !tnl_ioctl_get_6rd(p->name, &ip6rd) && ip6rd.prefixlen) {
print_string(PRINT_ANY, "6rd-prefix", " 6rd-prefix %s",
inet_ntop(AF_INET6, &ip6rd.prefix, b1, sizeof(b1)));
print_uint(PRINT_ANY, "6rd-prefixlen", "/%u", ip6rd.prefixlen);
if (ip6rd.relay_prefix) {
print_string(PRINT_ANY, "6rd-relay_prefix",
" 6rd-relay_prefix %s",
format_host(AF_INET, 4, &ip6rd.relay_prefix));
print_uint(PRINT_ANY, "6rd-relay_prefixlen", "/%u",
ip6rd.relay_prefixlen);
}
}
tnl_print_gre_flags(p->iph.protocol, p->i_flags, p->o_flags,
p->i_key, p->o_key);
close_json_object();
}
static void ip_tunnel_parm_initialize(const struct tnl_print_nlmsg_info *info)
{
struct ip_tunnel_parm *p2 = info->p2;
memset(p2, 0, sizeof(*p2));
}
static bool ip_tunnel_parm_match(const struct tnl_print_nlmsg_info *info)
{
const struct ip_tunnel_parm *p1 = info->p1;
const struct ip_tunnel_parm *p2 = info->p2;
return ((!p1->link || p1->link == p2->link) &&
(!p1->name[0] || strcmp(p1->name, p2->name) == 0) &&
(!p1->iph.daddr || p1->iph.daddr == p2->iph.daddr) &&
(!p1->iph.saddr || p1->iph.saddr == p2->iph.saddr) &&
(!p1->i_key || p1->i_key == p2->i_key));
}
static int do_show(int argc, char **argv)
{
struct ip_tunnel_parm p, p1;
const char *basedev;
if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0)
return -1;
basedev = tnl_defname(&p);
if (!basedev) {
struct tnl_print_nlmsg_info info = {
.p1 = &p,
.p2 = &p1,
.init = ip_tunnel_parm_initialize,
.match = ip_tunnel_parm_match,
.print = print_tunnel,
};
return do_tunnels_list(&info);
}
if (tnl_get_ioctl(p.name[0] ? p.name : basedev, &p))
return -1;
print_tunnel(&p);
fputc('\n', stdout);
return 0;
}
static int do_prl(int argc, char **argv)
{
struct ip_tunnel_prl p = {};
int count = 0;
int cmd = 0;
const char *medium = NULL;
while (argc > 0) {
if (strcmp(*argv, "prl-default") == 0) {
NEXT_ARG();
cmd = SIOCADDPRL;
p.addr = get_addr32(*argv);
p.flags |= PRL_DEFAULT;
count++;
} else if (strcmp(*argv, "prl-nodefault") == 0) {
NEXT_ARG();
cmd = SIOCADDPRL;
p.addr = get_addr32(*argv);
count++;
} else if (strcmp(*argv, "prl-delete") == 0) {
NEXT_ARG();
cmd = SIOCDELPRL;
p.addr = get_addr32(*argv);
count++;
} else if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
if (check_ifname(*argv))
invarg("\"dev\" not a valid ifname", *argv);
medium = *argv;
} else {
fprintf(stderr,
"Invalid PRL parameter \"%s\"\n", *argv);
exit(-1);
}
if (count > 1) {
fprintf(stderr,
"One PRL entry at a time\n");
exit(-1);
}
argc--; argv++;
}
if (!medium) {
fprintf(stderr, "Must specify device\n");
exit(-1);
}
return tnl_prl_ioctl(cmd, medium, &p);
}
static int do_6rd(int argc, char **argv)
{
struct ip_tunnel_6rd ip6rd = {};
int cmd = 0;
const char *medium = NULL;
inet_prefix prefix;
while (argc > 0) {
if (strcmp(*argv, "6rd-prefix") == 0) {
NEXT_ARG();
if (get_prefix(&prefix, *argv, AF_INET6))
invarg("invalid 6rd_prefix\n", *argv);
cmd = SIOCADD6RD;
memcpy(&ip6rd.prefix, prefix.data, 16);
ip6rd.prefixlen = prefix.bitlen;
} else if (strcmp(*argv, "6rd-relay_prefix") == 0) {
NEXT_ARG();
if (get_prefix(&prefix, *argv, AF_INET))
invarg("invalid 6rd-relay_prefix\n", *argv);
cmd = SIOCADD6RD;
memcpy(&ip6rd.relay_prefix, prefix.data, 4);
ip6rd.relay_prefixlen = prefix.bitlen;
} else if (strcmp(*argv, "6rd-reset") == 0) {
cmd = SIOCDEL6RD;
} else if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
if (check_ifname(*argv))
invarg("\"dev\" not a valid ifname", *argv);
medium = *argv;
} else {
fprintf(stderr,
"Invalid 6RD parameter \"%s\"\n", *argv);
exit(-1);
}
argc--; argv++;
}
if (!medium) {
fprintf(stderr, "Must specify device\n");
exit(-1);
}
return tnl_6rd_ioctl(cmd, medium, &ip6rd);
}
static int tunnel_mode_is_ipv6(char *tunnel_mode)
{
static const char * const ipv6_modes[] = {
"ipv6/ipv6", "ip6ip6",
"vti6",
"ip/ipv6", "ipv4/ipv6", "ipip6", "ip4ip6",
"ip6gre", "gre/ipv6",
"any/ipv6", "any"
};
int i;
for (i = 0; i < ARRAY_SIZE(ipv6_modes); i++) {
if (strcmp(ipv6_modes[i], tunnel_mode) == 0)
return 1;
}
return 0;
}
int do_iptunnel(int argc, char **argv)
{
int i;
for (i = 0; i < argc - 1; i++) {
if (strcmp(argv[i], "mode") == 0) {
if (tunnel_mode_is_ipv6(argv[i + 1]))
preferred_family = AF_INET6;
break;
}
}
switch (preferred_family) {
case AF_UNSPEC:
preferred_family = AF_INET;
break;
case AF_INET:
break;
/*
* This is silly enough but we have no easy way to make it
* protocol-independent because of unarranged structure between
* IPv4 and IPv6.
*/
case AF_INET6:
return do_ip6tunnel(argc, argv);
default:
fprintf(stderr, "Unsupported protocol family: %d\n", preferred_family);
exit(-1);
}
if (argc > 0) {
if (matches(*argv, "add") == 0)
return do_add(SIOCADDTUNNEL, argc - 1, argv + 1);
if (matches(*argv, "change") == 0)
return do_add(SIOCCHGTUNNEL, argc - 1, argv + 1);
if (matches(*argv, "delete") == 0)
return do_del(argc - 1, argv + 1);
if (matches(*argv, "show") == 0 ||
matches(*argv, "lst") == 0 ||
matches(*argv, "list") == 0)
return do_show(argc - 1, argv + 1);
if (matches(*argv, "prl") == 0)
return do_prl(argc - 1, argv + 1);
if (matches(*argv, "6rd") == 0)
return do_6rd(argc - 1, argv + 1);
if (matches(*argv, "help") == 0)
usage();
} else
return do_show(0, NULL);
fprintf(stderr, "Command \"%s\" is unknown, try \"ip tunnel help\"\n", *argv);
exit(-1);
}