freebsd-dev/usr.bin/netstat/route.c
Alexander V. Chernikov 64dfea8651 netlink: add NETLINK/NETLINK_SUPPORT userland options.
Make userland tools such as netstat, route, arp and ndp use
 either netlink or rtsock interfaces based on the NETLINK_SUPPORT
 options.
Both NETLINK and NETLINK_SUPPORT options are turned on by default.

Reviewed By: eugen
Differential Revision: https://reviews.freebsd.org/D39148
2023-03-26 08:59:58 +00:00

737 lines
17 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1983, 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if 0
#ifndef lint
static char sccsid[] = "From: @(#)route.c 8.6 (Berkeley) 4/28/95";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netgraph/ng_socket.h>
#include <arpa/inet.h>
#include <ifaddrs.h>
#include <libutil.h>
#include <netdb.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include <err.h>
#include <libxo/xo.h>
#include "netstat.h"
#include "common.h"
#include "nl_defs.h"
/*
* Definitions for showing gateway flags.
*/
struct bits rt_bits[] = {
{ RTF_UP, 'U', "up" },
{ RTF_GATEWAY, 'G', "gateway" },
{ RTF_HOST, 'H', "host" },
{ RTF_REJECT, 'R', "reject" },
{ RTF_DYNAMIC, 'D', "dynamic" },
{ RTF_MODIFIED, 'M', "modified" },
{ RTF_DONE, 'd', "done" }, /* Completed -- for routing msgs only */
{ RTF_XRESOLVE, 'X', "xresolve" },
{ RTF_STATIC, 'S', "static" },
{ RTF_PROTO1, '1', "proto1" },
{ RTF_PROTO2, '2', "proto2" },
{ RTF_PROTO3, '3', "proto3" },
{ RTF_BLACKHOLE,'B', "blackhole" },
{ RTF_BROADCAST,'b', "broadcast" },
#ifdef RTF_LLINFO
{ RTF_LLINFO, 'L', "llinfo" },
#endif
{ 0 , 0, NULL }
};
#ifdef WITHOUT_NETLINK
static struct ifmap_entry *ifmap;
static size_t ifmap_size;
#endif
static struct timespec uptime;
static const char *netname4(in_addr_t, in_addr_t);
#ifdef INET6
static const char *netname6(struct sockaddr_in6 *, struct sockaddr_in6 *);
#endif
#ifdef WITHOUT_NETLINK
static void p_rtable_sysctl(int, int);
static void p_rtentry_sysctl(const char *name, struct rt_msghdr *);
#endif
static void domask(char *, size_t, u_long);
const uint32_t rt_default_weight = RT_DEFAULT_WEIGHT;
/*
* Print routing tables.
*/
void
routepr(int fibnum, int af)
{
size_t intsize;
int numfibs;
if (live == 0)
return;
intsize = sizeof(int);
if (fibnum == -1 &&
sysctlbyname("net.my_fibnum", &fibnum, &intsize, NULL, 0) == -1)
fibnum = 0;
if (sysctlbyname("net.fibs", &numfibs, &intsize, NULL, 0) == -1)
numfibs = 1;
if (fibnum < 0 || fibnum > numfibs - 1)
errx(EX_USAGE, "%d: invalid fib", fibnum);
/*
* Since kernel & userland use different timebase
* (time_uptime vs time_second) and we are reading kernel memory
* directly we should do rt_expire --> expire_time conversion.
*/
if (clock_gettime(CLOCK_UPTIME, &uptime) < 0)
err(EX_OSERR, "clock_gettime() failed");
xo_open_container("route-information");
xo_emit("{T:Routing tables}");
if (fibnum)
xo_emit(" ({L:fib}: {:fib/%d})", fibnum);
xo_emit("\n");
#ifdef WITHOUT_NETLINK
p_rtable_sysctl(fibnum, af);
#else
p_rtable_netlink(fibnum, af);
#endif
xo_close_container("route-information");
}
/*
* Print address family header before a section of the routing table.
*/
void
pr_family(int af1)
{
const char *afname;
switch (af1) {
case AF_INET:
afname = "Internet";
break;
#ifdef INET6
case AF_INET6:
afname = "Internet6";
break;
#endif /*INET6*/
case AF_ISO:
afname = "ISO";
break;
case AF_CCITT:
afname = "X.25";
break;
case AF_NETGRAPH:
afname = "Netgraph";
break;
default:
afname = NULL;
break;
}
if (afname)
xo_emit("\n{k:address-family/%s}:\n", afname);
else
xo_emit("\n{L:Protocol Family} {k:address-family/%d}:\n", af1);
}
/* column widths; each followed by one space */
#ifndef INET6
#define WID_DST_DEFAULT(af) 18 /* width of destination column */
#define WID_GW_DEFAULT(af) 18 /* width of gateway column */
#define WID_IF_DEFAULT(af) (Wflag ? 10 : 8) /* width of netif column */
#else
#define WID_DST_DEFAULT(af) \
((af) == AF_INET6 ? (numeric_addr ? 33: 18) : 18)
#define WID_GW_DEFAULT(af) \
((af) == AF_INET6 ? (numeric_addr ? 29 : 18) : 18)
#define WID_IF_DEFAULT(af) ((af) == AF_INET6 ? 8 : (Wflag ? 10 : 8))
#endif /*INET6*/
struct _wid wid;
/*
* Print header for routing table columns.
*/
void
pr_rthdr(int af1 __unused)
{
if (Wflag) {
xo_emit("{T:/%-*.*s} {T:/%-*.*s} {T:/%-*.*s} {T:/%*.*s} "
"{T:/%*.*s} {T:/%*.*s} {T:/%*s}\n",
wid.dst, wid.dst, "Destination",
wid.gw, wid.gw, "Gateway",
wid.flags, wid.flags, "Flags",
wid.mtu, wid.mtu, "Nhop#",
wid.mtu, wid.mtu, "Mtu",
wid.iface, wid.iface, "Netif",
wid.expire, "Expire");
} else {
xo_emit("{T:/%-*.*s} {T:/%-*.*s} {T:/%-*.*s} {T:/%*.*s} "
"{T:/%*s}\n",
wid.dst, wid.dst, "Destination",
wid.gw, wid.gw, "Gateway",
wid.flags, wid.flags, "Flags",
wid.iface, wid.iface, "Netif",
wid.expire, "Expire");
}
}
void
set_wid(int fam)
{
wid.dst = WID_DST_DEFAULT(fam);
wid.gw = WID_GW_DEFAULT(fam);
wid.flags = 6;
wid.pksent = 8;
wid.mtu = 6;
wid.iface = WID_IF_DEFAULT(fam);
wid.expire = 6;
}
#ifdef WITHOUT_NETLINK
static void
p_rtable_sysctl(int fibnum, int af)
{
size_t needed;
int mib[7];
char *buf, *next, *lim;
struct rt_msghdr *rtm;
struct sockaddr *sa;
int fam = AF_UNSPEC;
int need_table_close = false;
ifmap = prepare_ifmap(&ifmap_size);
mib[0] = CTL_NET;
mib[1] = PF_ROUTE;
mib[2] = 0;
mib[3] = af;
mib[4] = NET_RT_DUMP;
mib[5] = 0;
mib[6] = fibnum;
if (sysctl(mib, nitems(mib), NULL, &needed, NULL, 0) < 0)
err(EX_OSERR, "sysctl: net.route.0.%d.dump.%d estimate", af,
fibnum);
if ((buf = malloc(needed)) == NULL)
errx(2, "malloc(%lu)", (unsigned long)needed);
if (sysctl(mib, nitems(mib), buf, &needed, NULL, 0) < 0)
err(1, "sysctl: net.route.0.%d.dump.%d", af, fibnum);
lim = buf + needed;
xo_open_container("route-table");
xo_open_list("rt-family");
for (next = buf; next < lim; next += rtm->rtm_msglen) {
rtm = (struct rt_msghdr *)next;
if (rtm->rtm_version != RTM_VERSION)
continue;
/*
* Peek inside header to determine AF
*/
sa = (struct sockaddr *)(rtm + 1);
/* Only print family first time. */
if (fam != sa->sa_family) {
if (need_table_close) {
xo_close_list("rt-entry");
xo_close_instance("rt-family");
}
need_table_close = true;
fam = sa->sa_family;
set_wid(fam);
xo_open_instance("rt-family");
pr_family(fam);
xo_open_list("rt-entry");
pr_rthdr(fam);
}
p_rtentry_sysctl("rt-entry", rtm);
}
if (need_table_close) {
xo_close_list("rt-entry");
xo_close_instance("rt-family");
}
xo_close_list("rt-family");
xo_close_container("route-table");
free(buf);
}
static void
p_rtentry_sysctl(const char *name, struct rt_msghdr *rtm)
{
struct sockaddr *sa, *addr[RTAX_MAX];
char buffer[128];
char prettyname[128];
int i, protrusion;
xo_open_instance(name);
sa = (struct sockaddr *)(rtm + 1);
for (i = 0; i < RTAX_MAX; i++) {
if (rtm->rtm_addrs & (1 << i)) {
addr[i] = sa;
sa = (struct sockaddr *)((char *)sa + SA_SIZE(sa));
}
}
protrusion = p_sockaddr("destination", addr[RTAX_DST],
addr[RTAX_NETMASK],
rtm->rtm_flags, wid.dst);
protrusion = p_sockaddr("gateway", addr[RTAX_GATEWAY], NULL, RTF_HOST,
wid.gw - protrusion);
snprintf(buffer, sizeof(buffer), "{[:-%d}{:flags/%%s}{]:} ",
wid.flags - protrusion);
p_flags(rtm->rtm_flags, buffer);
/* Output path weight as non-visual property */
xo_emit("{e:weight/%u}", rtm->rtm_rmx.rmx_weight);
if (Wflag) {
/* XXX: use=0? */
xo_emit("{t:nhop/%*lu} ", wid.mtu, rtm->rtm_rmx.rmx_nhidx);
if (rtm->rtm_rmx.rmx_mtu != 0)
xo_emit("{t:mtu/%*lu} ", wid.mtu, rtm->rtm_rmx.rmx_mtu);
else
xo_emit("{P:/%*s} ", wid.mtu, "");
}
memset(prettyname, 0, sizeof(prettyname));
if (rtm->rtm_index < ifmap_size) {
strlcpy(prettyname, ifmap[rtm->rtm_index].ifname,
sizeof(prettyname));
if (*prettyname == '\0')
strlcpy(prettyname, "---", sizeof(prettyname));
}
if (Wflag)
xo_emit("{t:interface-name/%*s}", wid.iface, prettyname);
else
xo_emit("{t:interface-name/%*.*s}", wid.iface, wid.iface,
prettyname);
if (rtm->rtm_rmx.rmx_expire) {
time_t expire_time;
if ((expire_time = rtm->rtm_rmx.rmx_expire - uptime.tv_sec) > 0)
xo_emit(" {:expire-time/%*d}", wid.expire,
(int)expire_time);
}
xo_emit("\n");
xo_close_instance(name);
}
#endif
int
p_sockaddr(const char *name, struct sockaddr *sa, struct sockaddr *mask,
int flags, int width)
{
const char *cp;
char buf[128];
int protrusion;
cp = fmt_sockaddr(sa, mask, flags);
if (width < 0) {
snprintf(buf, sizeof(buf), "{:%s/%%s} ", name);
xo_emit(buf, cp);
protrusion = 0;
} else {
if (Wflag != 0 || numeric_addr) {
snprintf(buf, sizeof(buf), "{[:%d}{:%s/%%s}{]:} ",
-width, name);
xo_emit(buf, cp);
protrusion = strlen(cp) - width;
if (protrusion < 0)
protrusion = 0;
} else {
snprintf(buf, sizeof(buf), "{[:%d}{:%s/%%-.*s}{]:} ",
-width, name);
xo_emit(buf, width, cp);
protrusion = 0;
}
}
return (protrusion);
}
const char *
fmt_sockaddr(struct sockaddr *sa, struct sockaddr *mask, int flags)
{
static char buf[128];
const char *cp;
if (sa == NULL)
return ("null");
switch(sa->sa_family) {
#ifdef INET6
case AF_INET6:
/*
* The sa6->sin6_scope_id must be filled here because
* this sockaddr is extracted from kmem(4) directly
* and has KAME-specific embedded scope id in
* sa6->sin6_addr.s6_addr[2].
*/
in6_fillscopeid(satosin6(sa));
/* FALLTHROUGH */
#endif /*INET6*/
case AF_INET:
if (flags & RTF_HOST)
cp = routename(sa, numeric_addr);
else if (mask)
cp = netname(sa, mask);
else
cp = netname(sa, NULL);
break;
case AF_NETGRAPH:
{
strlcpy(buf, ((struct sockaddr_ng *)sa)->sg_data,
sizeof(buf));
cp = buf;
break;
}
case AF_LINK:
{
#if 0
struct sockaddr_dl *sdl = (struct sockaddr_dl *)sa;
/* Interface route. */
if (sdl->sdl_nlen)
cp = sdl->sdl_data;
else
#endif
cp = routename(sa, 1);
break;
}
default:
{
u_char *s = (u_char *)sa->sa_data, *slim;
char *cq, *cqlim;
cq = buf;
slim = sa->sa_len + (u_char *) sa;
cqlim = cq + sizeof(buf) - sizeof(" ffff");
snprintf(cq, sizeof(buf), "(%d)", sa->sa_family);
cq += strlen(cq);
while (s < slim && cq < cqlim) {
snprintf(cq, sizeof(" ff"), " %02x", *s++);
cq += strlen(cq);
if (s < slim) {
snprintf(cq, sizeof("ff"), "%02x", *s++);
cq += strlen(cq);
}
}
cp = buf;
}
}
return (cp);
}
void
p_flags(int f, const char *format)
{
print_flags_generic(f, rt_bits, format, "flags_pretty");
}
char *
routename(struct sockaddr *sa, int flags)
{
static char line[NI_MAXHOST];
int error, f;
f = (flags) ? NI_NUMERICHOST : 0;
error = getnameinfo(sa, sa->sa_len, line, sizeof(line),
NULL, 0, f);
if (error) {
const void *src;
switch (sa->sa_family) {
#ifdef INET
case AF_INET:
src = &satosin(sa)->sin_addr;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
src = &satosin6(sa)->sin6_addr;
break;
#endif /* INET6 */
default:
return(line);
}
inet_ntop(sa->sa_family, src, line, sizeof(line) - 1);
return (line);
}
trimdomain(line, strlen(line));
return (line);
}
#define NSHIFT(m) ( \
(m) == IN_CLASSA_NET ? IN_CLASSA_NSHIFT : \
(m) == IN_CLASSB_NET ? IN_CLASSB_NSHIFT : \
(m) == IN_CLASSC_NET ? IN_CLASSC_NSHIFT : \
0)
static void
domask(char *dst, size_t buflen, u_long mask)
{
int b, i;
if (mask == 0) {
*dst = '\0';
return;
}
i = 0;
for (b = 0; b < 32; b++)
if (mask & (1 << b)) {
int bb;
i = b;
for (bb = b+1; bb < 32; bb++)
if (!(mask & (1 << bb))) {
i = -1; /* noncontig */
break;
}
break;
}
if (i == -1)
snprintf(dst, buflen, "&0x%lx", mask);
else
snprintf(dst, buflen, "/%d", 32-i);
}
/*
* Return the name of the network whose address is given.
*/
const char *
netname(struct sockaddr *sa, struct sockaddr *mask)
{
switch (sa->sa_family) {
case AF_INET:
if (mask != NULL)
return (netname4(satosin(sa)->sin_addr.s_addr,
satosin(mask)->sin_addr.s_addr));
else
return (netname4(satosin(sa)->sin_addr.s_addr,
INADDR_ANY));
break;
#ifdef INET6
case AF_INET6:
return (netname6(satosin6(sa), satosin6(mask)));
#endif /* INET6 */
default:
return (NULL);
}
}
static const char *
netname4(in_addr_t in, in_addr_t mask)
{
char *cp = 0;
static char line[MAXHOSTNAMELEN + sizeof("&0xffffffff")];
char nline[INET_ADDRSTRLEN];
struct netent *np = 0;
in_addr_t i;
if (in == INADDR_ANY && mask == 0) {
strlcpy(line, "default", sizeof(line));
return (line);
}
/* It is ok to supply host address. */
in &= mask;
i = ntohl(in);
if (!numeric_addr && i) {
np = getnetbyaddr(i >> NSHIFT(ntohl(mask)), AF_INET);
if (np != NULL) {
cp = np->n_name;
trimdomain(cp, strlen(cp));
}
}
if (cp != NULL)
strlcpy(line, cp, sizeof(line));
else {
inet_ntop(AF_INET, &in, nline, sizeof(nline));
strlcpy(line, nline, sizeof(line));
domask(line + strlen(line), sizeof(line) - strlen(line), ntohl(mask));
}
return (line);
}
#undef NSHIFT
#ifdef INET6
void
in6_fillscopeid(struct sockaddr_in6 *sa6)
{
#if defined(__KAME__)
/*
* XXX: This is a special workaround for KAME kernels.
* sin6_scope_id field of SA should be set in the future.
*/
if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr) ||
IN6_IS_ADDR_MC_NODELOCAL(&sa6->sin6_addr) ||
IN6_IS_ADDR_MC_LINKLOCAL(&sa6->sin6_addr)) {
if (sa6->sin6_scope_id == 0)
sa6->sin6_scope_id =
ntohs(*(u_int16_t *)&sa6->sin6_addr.s6_addr[2]);
sa6->sin6_addr.s6_addr[2] = sa6->sin6_addr.s6_addr[3] = 0;
}
#endif
}
/* Mask to length table. To check an invalid value, (length + 1) is used. */
static const u_char masktolen[256] = {
[0xff] = 8 + 1,
[0xfe] = 7 + 1,
[0xfc] = 6 + 1,
[0xf8] = 5 + 1,
[0xf0] = 4 + 1,
[0xe0] = 3 + 1,
[0xc0] = 2 + 1,
[0x80] = 1 + 1,
[0x00] = 0 + 1,
};
static const char *
netname6(struct sockaddr_in6 *sa6, struct sockaddr_in6 *mask)
{
static char line[NI_MAXHOST + sizeof("/xxx") - 1];
struct sockaddr_in6 addr;
char nline[NI_MAXHOST];
char maskbuf[sizeof("/xxx")];
u_char *p, *lim;
u_char masklen;
int i;
bool illegal = false;
if (mask) {
p = (u_char *)&mask->sin6_addr;
for (masklen = 0, lim = p + 16; p < lim; p++) {
if (masktolen[*p] > 0) {
/* -1 is required. */
masklen += (masktolen[*p] - 1);
} else
illegal = true;
}
if (illegal)
xo_error("illegal prefixlen\n");
memcpy(&addr, sa6, sizeof(addr));
for (i = 0; i < 16; ++i)
addr.sin6_addr.s6_addr[i] &=
mask->sin6_addr.s6_addr[i];
sa6 = &addr;
}
else
masklen = 128;
if (masklen == 0 && IN6_IS_ADDR_UNSPECIFIED(&sa6->sin6_addr))
return("default");
getnameinfo((struct sockaddr *)sa6, sa6->sin6_len, nline, sizeof(nline),
NULL, 0, NI_NUMERICHOST);
if (numeric_addr)
strlcpy(line, nline, sizeof(line));
else
getnameinfo((struct sockaddr *)sa6, sa6->sin6_len, line,
sizeof(line), NULL, 0, 0);
if (numeric_addr || strcmp(line, nline) == 0) {
snprintf(maskbuf, sizeof(maskbuf), "/%d", masklen);
strlcat(line, maskbuf, sizeof(line));
}
return (line);
}
#endif /*INET6*/
/*
* Print routing statistics
*/
void
rt_stats(void)
{
struct rtstat rtstat;
u_long rtsaddr;
if ((rtsaddr = nl[N_RTSTAT].n_value) == 0) {
xo_emit("{W:rtstat: symbol not in namelist}\n");
return;
}
kread_counters(rtsaddr, (char *)&rtstat, sizeof (rtstat));
xo_emit("{T:routing}:\n");
#define p(f, m) if (rtstat.f || sflag <= 1) \
xo_emit(m, rtstat.f, plural(rtstat.f))
p(rts_badredirect, "\t{:bad-redirects/%ju} "
"{N:/bad routing redirect%s}\n");
p(rts_dynamic, "\t{:dynamically-created/%ju} "
"{N:/dynamically created route%s}\n");
p(rts_newgateway, "\t{:new-gateways/%ju} "
"{N:/new gateway%s due to redirects}\n");
p(rts_unreach, "\t{:unreachable-destination/%ju} "
"{N:/destination%s found unreachable}\n");
p(rts_wildcard, "\t{:wildcard-uses/%ju} "
"{N:/use%s of a wildcard route}\n");
#undef p
}