iproute2/ip/ipmonitor.c
Benjamin Poirier 683a8b8d64 ip-monitor: Do not error out when RTNLGRP_STATS is not available
Following commit 4e8a9914c4 ("ip-monitor: Include stats events in default
and "all" cases"), `ip monitor` fails to start on kernels which do not
contain linux.git commit 5fd0b838efac ("net: rtnetlink: Add UAPI toggle for
IFLA_OFFLOAD_XSTATS_L3_STATS") because the netlink group RTNLGRP_STATS
doesn't exist:

 $ ip monitor
 Failed to add stats group to list

When "stats" is not explicitly requested, ignore the error so that `ip
monitor` and `ip monitor all` continue to work on older kernels.

Note that the same change is not done for RTNLGRP_NEXTHOP because its value
is 32 and group numbers <= 32 are always supported; see the comment above
netlink_change_ngroups() in the kernel source. Therefore
NETLINK_ADD_MEMBERSHIP 32 does not error out even on kernels which do not
support RTNLGRP_NEXTHOP.

v2:
* Silently ignore a failure to implicitly add the stats group, instead of
  printing a warning.

Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Fixes: 4e8a9914c4 ("ip-monitor: Include stats events in default and "all" cases")
Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
2022-10-26 08:53:24 -07:00

351 lines
8.3 KiB
C

/*
* ipmonitor.c "ip monitor".
*
* 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 <fcntl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <time.h>
#include "utils.h"
#include "ip_common.h"
#include "nh_common.h"
static void usage(void) __attribute__((noreturn));
static int prefix_banner;
int listen_all_nsid;
static void usage(void)
{
fprintf(stderr,
"Usage: ip monitor [ all | OBJECTS ] [ FILE ] [ label ] [ all-nsid ]\n"
" [ dev DEVICE ]\n"
"OBJECTS := address | link | mroute | neigh | netconf |\n"
" nexthop | nsid | prefix | route | rule | stats\n"
"FILE := file FILENAME\n");
exit(-1);
}
static void print_headers(FILE *fp, char *label, struct rtnl_ctrl_data *ctrl)
{
if (timestamp)
print_timestamp(fp);
if (listen_all_nsid) {
if (ctrl == NULL || ctrl->nsid < 0)
fprintf(fp, "[nsid current]");
else
fprintf(fp, "[nsid %d]", ctrl->nsid);
}
if (prefix_banner)
fprintf(fp, "%s", label);
}
static int accept_msg(struct rtnl_ctrl_data *ctrl,
struct nlmsghdr *n, void *arg)
{
FILE *fp = (FILE *)arg;
switch (n->nlmsg_type) {
case RTM_NEWROUTE:
case RTM_DELROUTE: {
struct rtmsg *r = NLMSG_DATA(n);
int len = n->nlmsg_len - NLMSG_LENGTH(sizeof(*r));
if (len < 0) {
fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
return -1;
}
if (r->rtm_flags & RTM_F_CLONED)
return 0;
if (r->rtm_family == RTNL_FAMILY_IPMR ||
r->rtm_family == RTNL_FAMILY_IP6MR) {
print_headers(fp, "[MROUTE]", ctrl);
print_mroute(n, arg);
return 0;
} else {
print_headers(fp, "[ROUTE]", ctrl);
print_route(n, arg);
return 0;
}
}
case RTM_NEWNEXTHOP:
case RTM_DELNEXTHOP:
print_headers(fp, "[NEXTHOP]", ctrl);
print_cache_nexthop(n, arg, true);
return 0;
case RTM_NEWNEXTHOPBUCKET:
case RTM_DELNEXTHOPBUCKET:
print_headers(fp, "[NEXTHOPBUCKET]", ctrl);
print_nexthop_bucket(n, arg);
return 0;
case RTM_NEWLINK:
case RTM_DELLINK:
ll_remember_index(n, NULL);
print_headers(fp, "[LINK]", ctrl);
print_linkinfo(n, arg);
return 0;
case RTM_NEWADDR:
case RTM_DELADDR:
print_headers(fp, "[ADDR]", ctrl);
print_addrinfo(n, arg);
return 0;
case RTM_NEWADDRLABEL:
case RTM_DELADDRLABEL:
print_headers(fp, "[ADDRLABEL]", ctrl);
print_addrlabel(n, arg);
return 0;
case RTM_NEWNEIGH:
case RTM_DELNEIGH:
case RTM_GETNEIGH:
if (preferred_family) {
struct ndmsg *r = NLMSG_DATA(n);
if (r->ndm_family != preferred_family)
return 0;
}
print_headers(fp, "[NEIGH]", ctrl);
print_neigh(n, arg);
return 0;
case RTM_NEWPREFIX:
print_headers(fp, "[PREFIX]", ctrl);
print_prefix(n, arg);
return 0;
case RTM_NEWRULE:
case RTM_DELRULE:
print_headers(fp, "[RULE]", ctrl);
print_rule(n, arg);
return 0;
case NLMSG_TSTAMP:
print_nlmsg_timestamp(fp, n);
return 0;
case RTM_NEWNETCONF:
case RTM_DELNETCONF:
print_headers(fp, "[NETCONF]", ctrl);
print_netconf(ctrl, n, arg);
return 0;
case RTM_DELNSID:
case RTM_NEWNSID:
print_headers(fp, "[NSID]", ctrl);
print_nsid(n, arg);
return 0;
case RTM_NEWSTATS:
print_headers(fp, "[STATS]", ctrl);
ipstats_print(n, arg);
return 0;
case NLMSG_ERROR:
case NLMSG_NOOP:
case NLMSG_DONE:
break; /* ignore */
default:
fprintf(stderr,
"Unknown message: type=0x%08x(%d) flags=0x%08x(%d) len=0x%08x(%d)\n",
n->nlmsg_type, n->nlmsg_type,
n->nlmsg_flags, n->nlmsg_flags, n->nlmsg_len,
n->nlmsg_len);
}
return 0;
}
#define IPMON_LLINK BIT(0)
#define IPMON_LADDR BIT(1)
#define IPMON_LROUTE BIT(2)
#define IPMON_LMROUTE BIT(3)
#define IPMON_LPREFIX BIT(4)
#define IPMON_LNEIGH BIT(5)
#define IPMON_LNETCONF BIT(6)
#define IPMON_LSTATS BIT(7)
#define IPMON_LRULE BIT(8)
#define IPMON_LNSID BIT(9)
#define IPMON_LNEXTHOP BIT(10)
#define IPMON_L_ALL (~0)
int do_ipmonitor(int argc, char **argv)
{
unsigned int groups = 0, lmask = 0;
/* "needed" mask, failure to enable is an error */
unsigned int nmask;
char *file = NULL;
int ifindex = 0;
rtnl_close(&rth);
while (argc > 0) {
if (matches(*argv, "file") == 0) {
NEXT_ARG();
file = *argv;
} else if (matches(*argv, "label") == 0) {
prefix_banner = 1;
} else if (matches(*argv, "link") == 0) {
lmask |= IPMON_LLINK;
} else if (matches(*argv, "address") == 0) {
lmask |= IPMON_LADDR;
} else if (matches(*argv, "route") == 0) {
lmask |= IPMON_LROUTE;
} else if (matches(*argv, "mroute") == 0) {
lmask |= IPMON_LMROUTE;
} else if (matches(*argv, "prefix") == 0) {
lmask |= IPMON_LPREFIX;
} else if (matches(*argv, "neigh") == 0) {
lmask |= IPMON_LNEIGH;
} else if (matches(*argv, "netconf") == 0) {
lmask |= IPMON_LNETCONF;
} else if (matches(*argv, "rule") == 0) {
lmask |= IPMON_LRULE;
} else if (matches(*argv, "nsid") == 0) {
lmask |= IPMON_LNSID;
} else if (matches(*argv, "nexthop") == 0) {
lmask |= IPMON_LNEXTHOP;
} else if (strcmp(*argv, "stats") == 0) {
lmask |= IPMON_LSTATS;
} else if (strcmp(*argv, "all") == 0) {
prefix_banner = 1;
} else if (matches(*argv, "all-nsid") == 0) {
listen_all_nsid = 1;
} else if (matches(*argv, "help") == 0) {
usage();
} else if (strcmp(*argv, "dev") == 0) {
NEXT_ARG();
ifindex = ll_name_to_index(*argv);
if (!ifindex)
invarg("Device does not exist\n", *argv);
} else {
fprintf(stderr, "Argument \"%s\" is unknown, try \"ip monitor help\".\n", *argv);
exit(-1);
}
argc--; argv++;
}
ipaddr_reset_filter(1, ifindex);
iproute_reset_filter(ifindex);
ipmroute_reset_filter(ifindex);
ipneigh_reset_filter(ifindex);
ipnetconf_reset_filter(ifindex);
nmask = lmask;
if (!lmask)
lmask = IPMON_L_ALL;
if (lmask & IPMON_LLINK)
groups |= nl_mgrp(RTNLGRP_LINK);
if (lmask & IPMON_LADDR) {
if (!preferred_family || preferred_family == AF_INET)
groups |= nl_mgrp(RTNLGRP_IPV4_IFADDR);
if (!preferred_family || preferred_family == AF_INET6)
groups |= nl_mgrp(RTNLGRP_IPV6_IFADDR);
}
if (lmask & IPMON_LROUTE) {
if (!preferred_family || preferred_family == AF_INET)
groups |= nl_mgrp(RTNLGRP_IPV4_ROUTE);
if (!preferred_family || preferred_family == AF_INET6)
groups |= nl_mgrp(RTNLGRP_IPV6_ROUTE);
if (!preferred_family || preferred_family == AF_MPLS)
groups |= nl_mgrp(RTNLGRP_MPLS_ROUTE);
}
if (lmask & IPMON_LMROUTE) {
if (!preferred_family || preferred_family == AF_INET)
groups |= nl_mgrp(RTNLGRP_IPV4_MROUTE);
if (!preferred_family || preferred_family == AF_INET6)
groups |= nl_mgrp(RTNLGRP_IPV6_MROUTE);
}
if (lmask & IPMON_LPREFIX) {
if (!preferred_family || preferred_family == AF_INET6)
groups |= nl_mgrp(RTNLGRP_IPV6_PREFIX);
}
if (lmask & IPMON_LNEIGH) {
groups |= nl_mgrp(RTNLGRP_NEIGH);
}
if (lmask & IPMON_LNETCONF) {
if (!preferred_family || preferred_family == AF_INET)
groups |= nl_mgrp(RTNLGRP_IPV4_NETCONF);
if (!preferred_family || preferred_family == AF_INET6)
groups |= nl_mgrp(RTNLGRP_IPV6_NETCONF);
if (!preferred_family || preferred_family == AF_MPLS)
groups |= nl_mgrp(RTNLGRP_MPLS_NETCONF);
}
if (lmask & IPMON_LRULE) {
if (!preferred_family || preferred_family == AF_INET)
groups |= nl_mgrp(RTNLGRP_IPV4_RULE);
if (!preferred_family || preferred_family == AF_INET6)
groups |= nl_mgrp(RTNLGRP_IPV6_RULE);
}
if (lmask & IPMON_LNSID) {
groups |= nl_mgrp(RTNLGRP_NSID);
}
if (file) {
FILE *fp;
int err;
fp = fopen(file, "r");
if (fp == NULL) {
perror("Cannot fopen");
exit(-1);
}
err = rtnl_from_file(fp, accept_msg, stdout);
fclose(fp);
return err;
}
if (rtnl_open(&rth, groups) < 0)
exit(1);
if (lmask & IPMON_LNEXTHOP &&
rtnl_add_nl_group(&rth, RTNLGRP_NEXTHOP) < 0) {
fprintf(stderr, "Failed to add nexthop group to list\n");
exit(1);
}
if (lmask & IPMON_LSTATS &&
rtnl_add_nl_group(&rth, RTNLGRP_STATS) < 0 &&
nmask & IPMON_LSTATS) {
fprintf(stderr, "Failed to add stats group to list\n");
exit(1);
}
if (listen_all_nsid && rtnl_listen_all_nsid(&rth) < 0)
exit(1);
ll_init_map(&rth);
netns_nsid_socket_init();
netns_map_init();
if (rtnl_listen(&rth, accept_msg, stdout) < 0)
exit(2);
return 0;
}