freebsd-dev/sys/net/route/route_ddb.c
Alexander V. Chernikov da187ddb3d * Add rib_<add|del|change>_route() functions to manipulate the routing table.
The main driver for the change is the need to improve notification mechanism.
Currently callers guess the operation data based on the rtentry structure
 returned in case of successful operation result. There are two problems with
 this appoach. First is that it doesn't provide enough information for the
 upcoming multipath changes, where rtentry refers to a new nexthop group,
 and there is no way of guessing which paths were added during the change.
 Second is that some rtentry fields can change during notification and
 protecting from it by requiring customers to unlock rtentry is not desired.

Additionally, as the consumers such as rtsock do know which operation they
 request in advance, making explicit add/change/del versions of the functions
 makes sense, especially given the functions don't share a lot of code.

With that in mind, introduce rib_cmd_info notification structure and
 rib_<add|del|change>_route() functions, with mandatory rib_cmd_info pointer.
 It will be used in upcoming generalized notifications.

* Move definitions of the new functions and some other functions/structures
 used for the routing table manipulation to a separate header file,
 net/route/route_ctl.h. net/route.h is a frequently used file included in
 ~140 places in kernel, and 90% of the users don't need these definitions.

Reviewed by:		ae
Differential Revision:	https://reviews.freebsd.org/D25067
2020-06-01 20:49:42 +00:00

272 lines
6.4 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright 2019 Conrad Meyer <cem@FreeBSD.org>
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/ctype.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/syslog.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/rmlock.h>
#include <ddb/ddb.h>
#include <ddb/db_lex.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <net/route/nhop.h>
#include <net/route/route_ctl.h>
#include <net/route/route_var.h>
/*
* Unfortunately, RTF_ values are expressed as raw masks rather than powers of
* 2, so we cannot use them as nice C99 initializer indices below.
*/
static const char * const rtf_flag_strings[] = {
"UP",
"GATEWAY",
"HOST",
"REJECT",
"DYNAMIC",
"MODIFIED",
"DONE",
"UNUSED_0x80",
"UNUSED_0x100",
"XRESOLVE",
"LLDATA",
"STATIC",
"BLACKHOLE",
"UNUSED_0x2000",
"PROTO2",
"PROTO1",
"UNUSED_0x10000",
"UNUSED_0x20000",
"PROTO3",
"FIXEDMTU",
"PINNED",
"LOCAL",
"BROADCAST",
"MULTICAST",
/* Big gap. */
[28] = "STICKY",
[30] = "RNH_LOCKED",
[31] = "GWFLAG_COMPAT",
};
static const char * __pure
rt_flag_name(unsigned idx)
{
if (idx >= nitems(rtf_flag_strings))
return ("INVALID_FLAG");
if (rtf_flag_strings[idx] == NULL)
return ("UNKNOWN");
return (rtf_flag_strings[idx]);
}
static void
rt_dumpaddr_ddb(const char *name, const struct sockaddr *sa)
{
char buf[INET6_ADDRSTRLEN], *res;
res = NULL;
if (sa == NULL)
res = "NULL";
else if (sa->sa_family == AF_INET) {
res = inet_ntop(AF_INET,
&((const struct sockaddr_in *)sa)->sin_addr,
buf, sizeof(buf));
} else if (sa->sa_family == AF_INET6) {
res = inet_ntop(AF_INET6,
&((const struct sockaddr_in6 *)sa)->sin6_addr,
buf, sizeof(buf));
} else if (sa->sa_family == AF_LINK) {
res = "on link";
}
if (res != NULL) {
db_printf("%s <%s> ", name, res);
return;
}
db_printf("%s <af:%d> ", name, sa->sa_family);
}
static int
rt_dumpentry_ddb(struct radix_node *rn, void *arg __unused)
{
struct sockaddr_storage ss;
struct rtentry *rt;
struct nhop_object *nh;
int flags, idx;
/* If RNTORT is important, put it in a header. */
rt = (void *)rn;
nh = (struct nhop_object *)rt->rt_nhop;
rt_dumpaddr_ddb("dst", rt_key(rt));
rt_dumpaddr_ddb("gateway", &rt->rt_nhop->gw_sa);
rt_dumpaddr_ddb("netmask", rtsock_fix_netmask(rt_key(rt), rt_mask(rt),
&ss));
if ((nh->nh_ifp->if_flags & IFF_DYING) == 0) {
rt_dumpaddr_ddb("ifp", nh->nh_ifp->if_addr->ifa_addr);
rt_dumpaddr_ddb("ifa", nh->nh_ifa->ifa_addr);
}
db_printf("flags ");
flags = rt->rt_flags;
if (flags == 0)
db_printf("none");
while ((idx = ffs(flags)) > 0) {
idx--;
if (flags != rt->rt_flags)
db_printf(",");
db_printf("%s", rt_flag_name(idx));
flags &= ~(1ul << idx);
}
db_printf("\n");
return (0);
}
DB_SHOW_COMMAND(routetable, db_show_routetable_cmd)
{
struct rib_head *rnh;
int error, i, lim;
if (have_addr)
i = lim = addr;
else {
i = 1;
lim = AF_MAX;
}
for (; i <= lim; i++) {
rnh = rt_tables_get_rnh(0, i);
if (rnh == NULL) {
if (have_addr) {
db_printf("%s: AF %d not supported?\n",
__func__, i);
break;
}
continue;
}
if (!have_addr && i > 1)
db_printf("\n");
db_printf("Route table for AF %d%s%s%s:\n", i,
(i == AF_INET || i == AF_INET6) ? " (" : "",
(i == AF_INET) ? "INET" : (i == AF_INET6) ? "INET6" : "",
(i == AF_INET || i == AF_INET6) ? ")" : "");
error = rnh->rnh_walktree(&rnh->head, rt_dumpentry_ddb, NULL);
if (error != 0)
db_printf("%s: walktree(%d): %d\n", __func__, i,
error);
}
}
_DB_FUNC(_show, route, db_show_route_cmd, db_show_table, CS_OWN, NULL)
{
char abuf[INET6_ADDRSTRLEN], *buf, *end;
struct rib_head *rh;
struct radix_node *rn;
void *dst_addrp;
struct rtentry *rt;
union {
struct sockaddr_in dest_sin;
struct sockaddr_in6 dest_sin6;
} u;
int af;
buf = db_get_line();
/* Remove whitespaces from both ends */
end = buf + strlen(buf) - 1;
for (; (end >= buf) && (*end=='\n' || isspace(*end)); end--)
*end = '\0';
while (isspace(*buf))
buf++;
/* Determine AF */
if (strchr(buf, ':') != NULL) {
af = AF_INET6;
u.dest_sin6.sin6_family = af;
u.dest_sin6.sin6_len = sizeof(struct sockaddr_in6);
dst_addrp = &u.dest_sin6.sin6_addr;
} else {
af = AF_INET;
u.dest_sin.sin_family = af;
u.dest_sin.sin_len = sizeof(struct sockaddr_in);
dst_addrp = &u.dest_sin.sin_addr;
}
if (inet_pton(af, buf, dst_addrp) != 1)
goto usage;
if (inet_ntop(af, dst_addrp, abuf, sizeof(abuf)) != NULL)
db_printf("Looking up route to destination '%s'\n", abuf);
rt = NULL;
CURVNET_SET(vnet0);
rh = rt_tables_get_rnh(RT_DEFAULT_FIB, af);
rn = rh->rnh_matchaddr(&u, &rh->head);
if (rn && ((rn->rn_flags & RNF_ROOT) == 0))
rt = (struct rtentry *)rn;
CURVNET_RESTORE();
if (rt == NULL) {
db_printf("Could not get route for that server.\n");
return;
}
rt_dumpentry_ddb((void *)rt, NULL);
return;
usage:
db_printf("Usage: 'show route <address>'\n"
" Currently accepts only IPv4 and IPv6 addresses\n");
db_skip_to_eol();
}