mirror_iproute2/ip/ipneigh.c
Hangbin Liu 86bf43c7c2 lib/libnetlink: update rtnl_talk to support malloc buff at run time
This is an update for 460c03f3f3 ("iplink: double the buffer size also in
iplink_get()"). After update, we will not need to double the buffer size
every time when VFs number increased.

With call like rtnl_talk(&rth, &req.n, NULL, 0), we can simply remove the
length parameter.

With call like rtnl_talk(&rth, nlh, nlh, sizeof(req), I add a new variable
answer to avoid overwrite data in nlh, because it may has more info after
nlh. also this will avoid nlh buffer not enough issue.

We need to free answer after using.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Phil Sutter <phil@nwl.cc>
2017-10-26 12:29:29 +02:00

526 lines
13 KiB
C

/*
* ipneigh.c "ip neigh".
*
* 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 <string.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include "rt_names.h"
#include "utils.h"
#include "ip_common.h"
#define NUD_VALID (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE|NUD_PROBE|NUD_STALE|NUD_DELAY)
#define MAX_ROUNDS 10
static struct
{
int family;
int index;
int state;
int unused_only;
inet_prefix pfx;
int flushed;
char *flushb;
int flushp;
int flushe;
int master;
} filter;
static void usage(void) __attribute__((noreturn));
static void usage(void)
{
fprintf(stderr, "Usage: ip neigh { add | del | change | replace }\n"
" { ADDR [ lladdr LLADDR ] [ nud STATE ] | proxy ADDR } [ dev DEV ]\n");
fprintf(stderr, " ip neigh { show | flush } [ proxy ] [ to PREFIX ] [ dev DEV ] [ nud STATE ]\n");
fprintf(stderr, " [ vrf NAME ]\n\n");
fprintf(stderr, "STATE := { permanent | noarp | stale | reachable | none |\n"
" incomplete | delay | probe | failed }\n");
exit(-1);
}
static int nud_state_a2n(unsigned int *state, const char *arg)
{
if (matches(arg, "permanent") == 0)
*state = NUD_PERMANENT;
else if (matches(arg, "reachable") == 0)
*state = NUD_REACHABLE;
else if (strcmp(arg, "noarp") == 0)
*state = NUD_NOARP;
else if (strcmp(arg, "none") == 0)
*state = NUD_NONE;
else if (strcmp(arg, "stale") == 0)
*state = NUD_STALE;
else if (strcmp(arg, "incomplete") == 0)
*state = NUD_INCOMPLETE;
else if (strcmp(arg, "delay") == 0)
*state = NUD_DELAY;
else if (strcmp(arg, "probe") == 0)
*state = NUD_PROBE;
else if (matches(arg, "failed") == 0)
*state = NUD_FAILED;
else {
if (get_unsigned(state, arg, 0))
return -1;
if (*state >= 0x100 || (*state&((*state)-1)))
return -1;
}
return 0;
}
static int flush_update(void)
{
if (rtnl_send_check(&rth, filter.flushb, filter.flushp) < 0) {
perror("Failed to send flush request");
return -1;
}
filter.flushp = 0;
return 0;
}
static int ipneigh_modify(int cmd, int flags, int argc, char **argv)
{
struct {
struct nlmsghdr n;
struct ndmsg ndm;
char buf[256];
} req = {
.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
.n.nlmsg_flags = NLM_F_REQUEST | flags,
.n.nlmsg_type = cmd,
.ndm.ndm_family = preferred_family,
.ndm.ndm_state = NUD_PERMANENT,
};
char *dev = NULL;
int dst_ok = 0;
int dev_ok = 0;
int lladdr_ok = 0;
char *lla = NULL;
inet_prefix dst;
while (argc > 0) {
if (matches(*argv, "lladdr") == 0) {
NEXT_ARG();
if (lladdr_ok)
duparg("lladdr", *argv);
lla = *argv;
lladdr_ok = 1;
} else if (strcmp(*argv, "nud") == 0) {
unsigned int state;
NEXT_ARG();
if (nud_state_a2n(&state, *argv))
invarg("nud state is bad", *argv);
req.ndm.ndm_state = state;
} else if (matches(*argv, "proxy") == 0) {
NEXT_ARG();
if (matches(*argv, "help") == 0)
usage();
if (dst_ok)
duparg("address", *argv);
get_addr(&dst, *argv, preferred_family);
dst_ok = 1;
dev_ok = 1;
req.ndm.ndm_flags |= NTF_PROXY;
} else if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
dev = *argv;
dev_ok = 1;
} else {
if (strcmp(*argv, "to") == 0) {
NEXT_ARG();
}
if (matches(*argv, "help") == 0) {
NEXT_ARG();
}
if (dst_ok)
duparg2("to", *argv);
get_addr(&dst, *argv, preferred_family);
dst_ok = 1;
}
argc--; argv++;
}
if (!dev_ok || !dst_ok || dst.family == AF_UNSPEC) {
fprintf(stderr, "Device and destination are required arguments.\n");
exit(-1);
}
req.ndm.ndm_family = dst.family;
if (addattr_l(&req.n, sizeof(req), NDA_DST, &dst.data, dst.bytelen) < 0)
return -1;
if (lla && strcmp(lla, "null")) {
char llabuf[20];
int l;
l = ll_addr_a2n(llabuf, sizeof(llabuf), lla);
if (l < 0)
return -1;
if (addattr_l(&req.n, sizeof(req), NDA_LLADDR, llabuf, l) < 0)
return -1;
}
ll_init_map(&rth);
if (dev && (req.ndm.ndm_ifindex = ll_name_to_index(dev)) == 0) {
fprintf(stderr, "Cannot find device \"%s\"\n", dev);
return -1;
}
if (rtnl_talk(&rth, &req.n, NULL) < 0)
exit(2);
return 0;
}
int print_neigh(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
{
FILE *fp = (FILE *)arg;
struct ndmsg *r = NLMSG_DATA(n);
int len = n->nlmsg_len;
struct rtattr *tb[NDA_MAX+1];
static int logit = 1;
if (n->nlmsg_type != RTM_NEWNEIGH && n->nlmsg_type != RTM_DELNEIGH &&
n->nlmsg_type != RTM_GETNEIGH) {
fprintf(stderr, "Not RTM_NEWNEIGH: %08x %08x %08x\n",
n->nlmsg_len, n->nlmsg_type, n->nlmsg_flags);
return 0;
}
len -= NLMSG_LENGTH(sizeof(*r));
if (len < 0) {
fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
return -1;
}
if (filter.flushb && n->nlmsg_type != RTM_NEWNEIGH)
return 0;
if (filter.family && filter.family != r->ndm_family)
return 0;
if (filter.index && filter.index != r->ndm_ifindex)
return 0;
if (!(filter.state&r->ndm_state) &&
!(r->ndm_flags & NTF_PROXY) &&
(r->ndm_state || !(filter.state&0x100)) &&
(r->ndm_family != AF_DECnet))
return 0;
if (filter.master && !(n->nlmsg_flags & NLM_F_DUMP_FILTERED)) {
if (logit) {
logit = 0;
fprintf(fp,
"\nWARNING: Kernel does not support filtering by master device\n\n");
}
}
parse_rtattr(tb, NDA_MAX, NDA_RTA(r), n->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));
if (tb[NDA_DST]) {
if (filter.pfx.family) {
inet_prefix dst = { .family = r->ndm_family };
memcpy(&dst.data, RTA_DATA(tb[NDA_DST]), RTA_PAYLOAD(tb[NDA_DST]));
if (inet_addr_match(&dst, &filter.pfx, filter.pfx.bitlen))
return 0;
}
}
if (filter.unused_only && tb[NDA_CACHEINFO]) {
struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
if (ci->ndm_refcnt)
return 0;
}
if (filter.flushb) {
struct nlmsghdr *fn;
if (NLMSG_ALIGN(filter.flushp) + n->nlmsg_len > filter.flushe) {
if (flush_update())
return -1;
}
fn = (struct nlmsghdr *)(filter.flushb + NLMSG_ALIGN(filter.flushp));
memcpy(fn, n, n->nlmsg_len);
fn->nlmsg_type = RTM_DELNEIGH;
fn->nlmsg_flags = NLM_F_REQUEST;
fn->nlmsg_seq = ++rth.seq;
filter.flushp = (((char *)fn) + n->nlmsg_len) - filter.flushb;
filter.flushed++;
if (show_stats < 2)
return 0;
}
if (n->nlmsg_type == RTM_DELNEIGH)
fprintf(fp, "Deleted ");
else if (n->nlmsg_type == RTM_GETNEIGH)
fprintf(fp, "miss ");
if (tb[NDA_DST]) {
fprintf(fp, "%s ",
format_host_rta(r->ndm_family, tb[NDA_DST]));
}
if (!filter.index && r->ndm_ifindex)
fprintf(fp, "dev %s ", ll_index_to_name(r->ndm_ifindex));
if (tb[NDA_LLADDR]) {
SPRINT_BUF(b1);
fprintf(fp, "lladdr %s", ll_addr_n2a(RTA_DATA(tb[NDA_LLADDR]),
RTA_PAYLOAD(tb[NDA_LLADDR]),
ll_index_to_type(r->ndm_ifindex),
b1, sizeof(b1)));
}
if (r->ndm_flags & NTF_ROUTER) {
fprintf(fp, " router");
}
if (r->ndm_flags & NTF_PROXY) {
fprintf(fp, " proxy");
}
if (tb[NDA_CACHEINFO] && show_stats) {
struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
int hz = get_user_hz();
if (ci->ndm_refcnt)
printf(" ref %d", ci->ndm_refcnt);
fprintf(fp, " used %d/%d/%d", ci->ndm_used/hz,
ci->ndm_confirmed/hz, ci->ndm_updated/hz);
}
if (tb[NDA_PROBES] && show_stats) {
__u32 p = rta_getattr_u32(tb[NDA_PROBES]);
fprintf(fp, " probes %u", p);
}
if (r->ndm_state) {
int nud = r->ndm_state;
fprintf(fp, " ");
#define PRINT_FLAG(f) if (nud & NUD_##f) { \
nud &= ~NUD_##f; fprintf(fp, #f "%s", nud ? "," : ""); }
PRINT_FLAG(INCOMPLETE);
PRINT_FLAG(REACHABLE);
PRINT_FLAG(STALE);
PRINT_FLAG(DELAY);
PRINT_FLAG(PROBE);
PRINT_FLAG(FAILED);
PRINT_FLAG(NOARP);
PRINT_FLAG(PERMANENT);
#undef PRINT_FLAG
}
fprintf(fp, "\n");
fflush(fp);
return 0;
}
void ipneigh_reset_filter(int ifindex)
{
memset(&filter, 0, sizeof(filter));
filter.state = ~0;
filter.index = ifindex;
}
static int do_show_or_flush(int argc, char **argv, int flush)
{
struct {
struct nlmsghdr n;
struct ndmsg ndm;
char buf[256];
} req = {
.n.nlmsg_type = RTM_GETNEIGH,
.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg)),
};
char *filter_dev = NULL;
int state_given = 0;
ipneigh_reset_filter(0);
if (!filter.family)
filter.family = preferred_family;
if (flush) {
if (argc <= 0) {
fprintf(stderr, "Flush requires arguments.\n");
return -1;
}
filter.state = ~(NUD_PERMANENT|NUD_NOARP);
} else
filter.state = 0xFF & ~NUD_NOARP;
while (argc > 0) {
if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
if (filter_dev)
duparg("dev", *argv);
filter_dev = *argv;
} else if (strcmp(*argv, "master") == 0) {
int ifindex;
NEXT_ARG();
ifindex = ll_name_to_index(*argv);
if (!ifindex)
invarg("Device does not exist\n", *argv);
addattr32(&req.n, sizeof(req), NDA_MASTER, ifindex);
filter.master = ifindex;
} else if (strcmp(*argv, "vrf") == 0) {
int ifindex;
NEXT_ARG();
ifindex = ll_name_to_index(*argv);
if (!ifindex)
invarg("Not a valid VRF name\n", *argv);
if (!name_is_vrf(*argv))
invarg("Not a valid VRF name\n", *argv);
addattr32(&req.n, sizeof(req), NDA_MASTER, ifindex);
filter.master = ifindex;
} else if (strcmp(*argv, "unused") == 0) {
filter.unused_only = 1;
} else if (strcmp(*argv, "nud") == 0) {
unsigned int state;
NEXT_ARG();
if (!state_given) {
state_given = 1;
filter.state = 0;
}
if (nud_state_a2n(&state, *argv)) {
if (strcmp(*argv, "all") != 0)
invarg("nud state is bad", *argv);
state = ~0;
if (flush)
state &= ~NUD_NOARP;
}
if (state == 0)
state = 0x100;
filter.state |= state;
} else if (strcmp(*argv, "proxy") == 0)
req.ndm.ndm_flags = NTF_PROXY;
else {
if (strcmp(*argv, "to") == 0) {
NEXT_ARG();
}
if (matches(*argv, "help") == 0)
usage();
get_prefix(&filter.pfx, *argv, filter.family);
if (filter.family == AF_UNSPEC)
filter.family = filter.pfx.family;
}
argc--; argv++;
}
ll_init_map(&rth);
if (filter_dev) {
if ((filter.index = ll_name_to_index(filter_dev)) == 0) {
fprintf(stderr, "Cannot find device \"%s\"\n", filter_dev);
return -1;
}
addattr32(&req.n, sizeof(req), NDA_IFINDEX, filter.index);
}
req.ndm.ndm_family = filter.family;
if (flush) {
int round = 0;
char flushb[4096-512];
filter.flushb = flushb;
filter.flushp = 0;
filter.flushe = sizeof(flushb);
while (round < MAX_ROUNDS) {
if (rtnl_dump_request_n(&rth, &req.n) < 0) {
perror("Cannot send dump request");
exit(1);
}
filter.flushed = 0;
if (rtnl_dump_filter(&rth, print_neigh, stdout) < 0) {
fprintf(stderr, "Flush terminated\n");
exit(1);
}
if (filter.flushed == 0) {
if (show_stats) {
if (round == 0)
printf("Nothing to flush.\n");
else
printf("*** Flush is complete after %d round%s ***\n", round, round > 1?"s":"");
}
fflush(stdout);
return 0;
}
round++;
if (flush_update() < 0)
exit(1);
if (show_stats) {
printf("\n*** Round %d, deleting %d entries ***\n", round, filter.flushed);
fflush(stdout);
}
filter.state &= ~NUD_FAILED;
}
printf("*** Flush not complete bailing out after %d rounds\n",
MAX_ROUNDS);
return 1;
}
if (rtnl_dump_request_n(&rth, &req.n) < 0) {
perror("Cannot send dump request");
exit(1);
}
if (rtnl_dump_filter(&rth, print_neigh, stdout) < 0) {
fprintf(stderr, "Dump terminated\n");
exit(1);
}
return 0;
}
int do_ipneigh(int argc, char **argv)
{
if (argc > 0) {
if (matches(*argv, "add") == 0)
return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_EXCL, argc-1, argv+1);
if (matches(*argv, "change") == 0 ||
strcmp(*argv, "chg") == 0)
return ipneigh_modify(RTM_NEWNEIGH, NLM_F_REPLACE, argc-1, argv+1);
if (matches(*argv, "replace") == 0)
return ipneigh_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_REPLACE, argc-1, argv+1);
if (matches(*argv, "delete") == 0)
return ipneigh_modify(RTM_DELNEIGH, 0, argc-1, argv+1);
if (matches(*argv, "get") == 0) {
fprintf(stderr, "Sorry, \"neigh get\" is not implemented :-(\n");
return -1;
}
if (matches(*argv, "show") == 0 ||
matches(*argv, "lst") == 0 ||
matches(*argv, "list") == 0)
return do_show_or_flush(argc-1, argv+1, 0);
if (matches(*argv, "flush") == 0)
return do_show_or_flush(argc-1, argv+1, 1);
if (matches(*argv, "help") == 0)
usage();
} else
return do_show_or_flush(0, NULL, 0);
fprintf(stderr, "Command \"%s\" is unknown, try \"ip neigh help\".\n", *argv);
exit(-1);
}