/*
* iprule.c "ip rule".
*
* 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 <unistd.h>
#include <syslog.h>
#include <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <string.h>
#include <linux/fib_rules.h>
#include "rt_names.h"
#include "utils.h"
#include "ip_common.h"
extern struct rtnl_handle rth;
static void usage(void) __attribute__((noreturn));
static void usage(void)
{
fprintf(stderr, "Usage: ip rule [ list | add | del | flush ] SELECTOR ACTION\n");
fprintf(stderr, "SELECTOR := [ not ] [ from PREFIX ] [ to PREFIX ] [ tos TOS ] [ fwmark FWMARK[/MASK] ]\n");
fprintf(stderr, " [ dev STRING ] [ pref NUMBER ]\n");
fprintf(stderr, "ACTION := [ table TABLE_ID ]\n");
fprintf(stderr, " [ prohibit | reject | unreachable ]\n");
fprintf(stderr, " [ realms [SRCREALM/]DSTREALM ]\n");
fprintf(stderr, " [ goto NUMBER ]\n");
fprintf(stderr, "TABLE_ID := [ local | main | default | NUMBER ]\n");
exit(-1);
}
int print_rule(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
{
FILE *fp = (FILE*)arg;
struct rtmsg *r = NLMSG_DATA(n);
int len = n->nlmsg_len;
int host_len = -1;
__u32 table;
struct rtattr * tb[FRA_MAX+1];
char abuf[256];
SPRINT_BUF(b1);
if (n->nlmsg_type != RTM_NEWRULE && n->nlmsg_type != RTM_DELRULE)
return 0;
len -= NLMSG_LENGTH(sizeof(*r));
if (len < 0)
return -1;
parse_rtattr(tb, FRA_MAX, RTM_RTA(r), len);
if (r->rtm_family == AF_INET)
host_len = 32;
else if (r->rtm_family == AF_INET6)
host_len = 128;
else if (r->rtm_family == AF_DECnet)
host_len = 16;
else if (r->rtm_family == AF_IPX)
host_len = 80;
if (n->nlmsg_type == RTM_DELRULE)
fprintf(fp, "Deleted ");
if (tb[FRA_PRIORITY])
fprintf(fp, "%u:\t", *(unsigned*)RTA_DATA(tb[FRA_PRIORITY]));
else
fprintf(fp, "0:\t");
if (r->rtm_flags & FIB_RULE_INVERT)
fprintf(fp, "not ");
if (tb[FRA_SRC]) {
if (r->rtm_src_len != host_len) {
fprintf(fp, "from %s/%u ", rt_addr_n2a(r->rtm_family,
RTA_PAYLOAD(tb[FRA_SRC]),
RTA_DATA(tb[FRA_SRC]),
abuf, sizeof(abuf)),
r->rtm_src_len
);
} else {
fprintf(fp, "from %s ", format_host(r->rtm_family,
RTA_PAYLOAD(tb[FRA_SRC]),
RTA_DATA(tb[FRA_SRC]),
abuf, sizeof(abuf))
);
}
} else if (r->rtm_src_len) {
fprintf(fp, "from 0/%d ", r->rtm_src_len);
} else {
fprintf(fp, "from all ");
}
if (tb[FRA_DST]) {
if (r->rtm_dst_len != host_len) {
fprintf(fp, "to %s/%u ", rt_addr_n2a(r->rtm_family,
RTA_PAYLOAD(tb[FRA_DST]),
RTA_DATA(tb[FRA_DST]),
abuf, sizeof(abuf)),
r->rtm_dst_len
);
} else {
fprintf(fp, "to %s ", format_host(r->rtm_family,
RTA_PAYLOAD(tb[FRA_DST]),
RTA_DATA(tb[FRA_DST]),
abuf, sizeof(abuf)));
}
} else if (r->rtm_dst_len) {
fprintf(fp, "to 0/%d ", r->rtm_dst_len);
}
if (r->rtm_tos) {
SPRINT_BUF(b1);
fprintf(fp, "tos %s ", rtnl_dsfield_n2a(r->rtm_tos, b1, sizeof(b1)));
}
if (tb[FRA_FWMARK] || tb[FRA_FWMASK]) {
__u32 mark = 0, mask = 0;
if (tb[FRA_FWMARK])
mark = *(__u32*)RTA_DATA(tb[FRA_FWMARK]);
if (tb[FRA_FWMASK] &&
(mask = *(__u32*)RTA_DATA(tb[FRA_FWMASK])) != 0xFFFFFFFF)
fprintf(fp, "fwmark 0x%x/0x%x ", mark, mask);
else
fprintf(fp, "fwmark 0x%x ", mark);
}
if (tb[FRA_IFNAME]) {
fprintf(fp, "iif %s ", (char*)RTA_DATA(tb[FRA_IFNAME]));
if (r->rtm_flags & FIB_RULE_DEV_DETACHED)
fprintf(fp, "[detached] ");
}
table = rtm_get_table(r, tb);
if (table)
fprintf(fp, "lookup %s ", rtnl_rttable_n2a(table, b1, sizeof(b1)));
if (tb[FRA_FLOW]) {
__u32 to = *(__u32*)RTA_DATA(tb[FRA_FLOW]);
__u32 from = to>>16;
to &= 0xFFFF;
if (from) {
fprintf(fp, "realms %s/",
rtnl_rtrealm_n2a(from, b1, sizeof(b1)));
}
fprintf(fp, "%s ",
rtnl_rtrealm_n2a(to, b1, sizeof(b1)));
}
if (r->rtm_type == RTN_NAT) {
if (tb[RTA_GATEWAY]) {
fprintf(fp, "map-to %s ",
format_host(r->rtm_family,
RTA_PAYLOAD(tb[RTA_GATEWAY]),
RTA_DATA(tb[RTA_GATEWAY]),
abuf, sizeof(abuf)));
} else
fprintf(fp, "masquerade");
} else if (r->rtm_type == FR_ACT_GOTO) {
fprintf(fp, "goto ");
if (tb[FRA_GOTO])
fprintf(fp, "%u", *(__u32 *) RTA_DATA(tb[FRA_GOTO]));
else
fprintf(fp, "none");
if (r->rtm_flags & FIB_RULE_UNRESOLVED)
fprintf(fp, " [unresolved]");
} else if (r->rtm_type == FR_ACT_NOP)
fprintf(fp, "nop");
else if (r->rtm_type != RTN_UNICAST)
fprintf(fp, "%s", rtnl_rtntype_n2a(r->rtm_type, b1, sizeof(b1)));
fprintf(fp, "\n");
fflush(fp);
return 0;
}
static int iprule_list(int argc, char **argv)
{
int af = preferred_family;
if (af == AF_UNSPEC)
af = AF_INET;
if (argc > 0) {
fprintf(stderr, "\"ip rule show\" does not take any arguments.\n");
return -1;
}
if (rtnl_wilddump_request(&rth, af, RTM_GETRULE) < 0) {
perror("Cannot send dump request");
return 1;
}
if (rtnl_dump_filter(&rth, print_rule, stdout, NULL, NULL) < 0) {
fprintf(stderr, "Dump terminated\n");
return 1;
}
return 0;
}
static int iprule_modify(int cmd, int argc, char **argv)
{
int table_ok = 0;
struct {
struct nlmsghdr n;
struct rtmsg r;
char buf[1024];
} req;
memset(&req, 0, sizeof(req));
req.n.nlmsg_type = cmd;
req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct rtmsg));
req.n.nlmsg_flags = NLM_F_REQUEST;
req.r.rtm_family = preferred_family;
req.r.rtm_protocol = RTPROT_BOOT;
req.r.rtm_scope = RT_SCOPE_UNIVERSE;
req.r.rtm_table = 0;
req.r.rtm_type = RTN_UNSPEC;
req.r.rtm_flags = 0;
if (cmd == RTM_NEWRULE) {
req.n.nlmsg_flags |= NLM_F_CREATE|NLM_F_EXCL;
req.r.rtm_type = RTN_UNICAST;
}
while (argc > 0) {
if (strcmp(*argv, "not") == 0) {
req.r.rtm_flags |= FIB_RULE_INVERT;
} else if (strcmp(*argv, "from") == 0) {
inet_prefix dst;
NEXT_ARG();
get_prefix(&dst, *argv, req.r.rtm_family);
req.r.rtm_src_len = dst.bitlen;
addattr_l(&req.n, sizeof(req), FRA_SRC, &dst.data, dst.bytelen);
} else if (strcmp(*argv, "to") == 0) {
inet_prefix dst;
NEXT_ARG();
get_prefix(&dst, *argv, req.r.rtm_family);
req.r.rtm_dst_len = dst.bitlen;
addattr_l(&req.n, sizeof(req), FRA_DST, &dst.data, dst.bytelen);
} else if (matches(*argv, "preference") == 0 ||
matches(*argv, "order") == 0 ||
matches(*argv, "priority") == 0) {
__u32 pref;
NEXT_ARG();
if (get_u32(&pref, *argv, 0))
invarg("preference value is invalid\n", *argv);
addattr32(&req.n, sizeof(req), FRA_PRIORITY, pref);
} else if (strcmp(*argv, "tos") == 0) {
__u32 tos;
NEXT_ARG();
if (rtnl_dsfield_a2n(&tos, *argv))
invarg("TOS value is invalid\n", *argv);
req.r.rtm_tos = tos;
} else if (strcmp(*argv, "fwmark") == 0) {
char *slash;
__u32 fwmark, fwmask;
NEXT_ARG();
if ((slash = strchr(*argv, '/')) != NULL)
*slash = '\0';
if (get_u32(&fwmark, *argv, 0))
invarg("fwmark value is invalid\n", *argv);
addattr32(&req.n, sizeof(req), FRA_FWMARK, fwmark);
if (slash) {
if (get_u32(&fwmask, slash+1, 0))
invarg("fwmask value is invalid\n", slash+1);
addattr32(&req.n, sizeof(req), FRA_FWMASK, fwmask);
}
} else if (matches(*argv, "realms") == 0) {
__u32 realm;
NEXT_ARG();
if (get_rt_realms(&realm, *argv))
invarg("invalid realms\n", *argv);
addattr32(&req.n, sizeof(req), FRA_FLOW, realm);
} else if (matches(*argv, "table") == 0 ||
strcmp(*argv, "lookup") == 0) {
__u32 tid;
NEXT_ARG();
if (rtnl_rttable_a2n(&tid, *argv))
invarg("invalid table ID\n", *argv);
if (tid < 256)
req.r.rtm_table = tid;
else {
req.r.rtm_table = RT_TABLE_UNSPEC;
addattr32(&req.n, sizeof(req), FRA_TABLE, tid);
}
table_ok = 1;
} else if (strcmp(*argv, "dev") == 0 ||
strcmp(*argv, "iif") == 0) {
NEXT_ARG();
addattr_l(&req.n, sizeof(req), FRA_IFNAME, *argv, strlen(*argv)+1);
} else if (strcmp(*argv, "nat") == 0 ||
matches(*argv, "map-to") == 0) {
NEXT_ARG();
fprintf(stderr, "Warning: route NAT is deprecated\n");
addattr32(&req.n, sizeof(req), RTA_GATEWAY, get_addr32(*argv));
req.r.rtm_type = RTN_NAT;
} else {
int type;
if (strcmp(*argv, "type") == 0) {
NEXT_ARG();
}
if (matches(*argv, "help") == 0)
usage();
else if (matches(*argv, "goto") == 0) {
__u32 target;
type = FR_ACT_GOTO;
NEXT_ARG();
if (get_u32(&target, *argv, 0))
invarg("invalid target\n", *argv);
addattr32(&req.n, sizeof(req), FRA_GOTO, target);
} else if (matches(*argv, "nop") == 0)
type = FR_ACT_NOP;
else if (rtnl_rtntype_a2n(&type, *argv))
invarg("Failed to parse rule type", *argv);
req.r.rtm_type = type;
table_ok = 1;
}
argc--;
argv++;
}
if (req.r.rtm_family == AF_UNSPEC)
req.r.rtm_family = AF_INET;
if (!table_ok && cmd == RTM_NEWRULE)
req.r.rtm_table = RT_TABLE_MAIN;
if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0)
return 2;
return 0;
}
static int flush_rule(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
{
struct rtnl_handle rth2;
struct rtmsg *r = NLMSG_DATA(n);
int len = n->nlmsg_len;
struct rtattr * tb[FRA_MAX+1];
len -= NLMSG_LENGTH(sizeof(*r));
if (len < 0)
return -1;
parse_rtattr(tb, FRA_MAX, RTM_RTA(r), len);
if (tb[FRA_PRIORITY]) {
n->nlmsg_type = RTM_DELRULE;
n->nlmsg_flags = NLM_F_REQUEST;
if (rtnl_open(&rth2, 0) < 0)
return -1;
if (rtnl_talk(&rth2, n, 0, 0, NULL, NULL, NULL) < 0)
return -2;
rtnl_close(&rth2);
}
return 0;
}
static int iprule_flush(int argc, char **argv)
{
int af = preferred_family;
if (af == AF_UNSPEC)
af = AF_INET;
if (argc > 0) {
fprintf(stderr, "\"ip rule flush\" does not allow arguments\n");
return -1;
}
if (rtnl_wilddump_request(&rth, af, RTM_GETRULE) < 0) {
perror("Cannot send dump request");
return 1;
}
if (rtnl_dump_filter(&rth, flush_rule, NULL, NULL, NULL) < 0) {
fprintf(stderr, "Flush terminated\n");
return 1;
}
return 0;
}
int do_iprule(int argc, char **argv)
{
if (argc < 1) {
return iprule_list(0, NULL);
} else if (matches(argv[0], "list") == 0 ||
matches(argv[0], "lst") == 0 ||
matches(argv[0], "show") == 0) {
return iprule_list(argc-1, argv+1);
} else if (matches(argv[0], "add") == 0) {
return iprule_modify(RTM_NEWRULE, argc-1, argv+1);
} else if (matches(argv[0], "delete") == 0) {
return iprule_modify(RTM_DELRULE, argc-1, argv+1);
} else if (matches(argv[0], "flush") == 0) {
return iprule_flush(argc-1, argv+1);
} else if (matches(argv[0], "help") == 0)
usage();
fprintf(stderr, "Command \"%s\" is unknown, try \"ip rule help\".\n", *argv);
exit(-1);
}