freebsd-nq/sbin/ipfw/ipv6.c
Andrey V. Elsukov 8f47ad010c Do not print "ip6" keyword in print_icmp6types() for O_ICMP6TYPE opcode.
It produces incompatibility when rules listing is used again to
restore saved ruleset, because "ip6" keyword produces separate opcode.
The kernel already has the check and only IPv6 packets will be checked
for matching.

PR:		232939
MFC after:	3 days
2018-11-06 07:41:32 +00:00

524 lines
12 KiB
C

/*-
* Copyright (c) 2002-2003 Luigi Rizzo
* Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
* Copyright (c) 1994 Ugen J.S.Antsilevich
*
* Idea and grammar partially left from:
* Copyright (c) 1993 Daniel Boulet
*
* Redistribution and use in source forms, with and without modification,
* are permitted provided that this entire comment appears intact.
*
* Redistribution in binary form may occur without any restrictions.
* Obviously, it would be nice if you gave credit where credit is due
* but requiring it would be too onerous.
*
* This software is provided ``AS IS'' without any warranties of any kind.
*
* NEW command line interface for IP firewall facility
*
* $FreeBSD$
*
* ipv6 support
*/
#include <sys/types.h>
#include <sys/socket.h>
#include "ipfw2.h"
#include <err.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <net/if.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/icmp6.h>
#include <netinet/ip_fw.h>
#include <arpa/inet.h>
#define CHECK_LENGTH(v, len) do { \
if ((v) < (len)) \
errx(EX_DATAERR, "Rule too long"); \
} while (0)
static struct _s_x icmp6codes[] = {
{ "no-route", ICMP6_DST_UNREACH_NOROUTE },
{ "admin-prohib", ICMP6_DST_UNREACH_ADMIN },
{ "address", ICMP6_DST_UNREACH_ADDR },
{ "port", ICMP6_DST_UNREACH_NOPORT },
{ NULL, 0 }
};
void
fill_unreach6_code(u_short *codep, char *str)
{
int val;
char *s;
val = strtoul(str, &s, 0);
if (s == str || *s != '\0' || val >= 0x100)
val = match_token(icmp6codes, str);
if (val < 0)
errx(EX_DATAERR, "unknown ICMPv6 unreachable code ``%s''", str);
*codep = val;
return;
}
void
print_unreach6_code(struct buf_pr *bp, uint16_t code)
{
char const *s = match_value(icmp6codes, code);
if (s != NULL)
bprintf(bp, "unreach6 %s", s);
else
bprintf(bp, "unreach6 %u", code);
}
/*
* Print the ip address contained in a command.
*/
void
print_ip6(struct buf_pr *bp, ipfw_insn_ip6 *cmd)
{
char trad[255];
struct hostent *he = NULL;
struct in6_addr *a = &(cmd->addr6);
int len, mb;
len = F_LEN((ipfw_insn *) cmd) - 1;
if (cmd->o.opcode == O_IP6_SRC_ME || cmd->o.opcode == O_IP6_DST_ME) {
bprintf(bp, " me6");
return;
}
if (cmd->o.opcode == O_IP6) {
bprintf(bp, " ip6");
return;
}
/*
* len == 4 indicates a single IP, whereas lists of 1 or more
* addr/mask pairs have len = (2n+1). We convert len to n so we
* use that to count the number of entries.
*/
bprintf(bp, " ");
for (len = len / 4; len > 0; len -= 2, a += 2) {
/* mask length */
mb = (cmd->o.opcode == O_IP6_SRC ||
cmd->o.opcode == O_IP6_DST) ? 128:
contigmask((uint8_t *)&(a[1]), 128);
if (mb == 128 && co.do_resolv)
he = gethostbyaddr((char *)a, sizeof(*a), AF_INET6);
if (he != NULL) /* resolved to name */
bprintf(bp, "%s", he->h_name);
else if (mb == 0) /* any */
bprintf(bp, "any");
else { /* numeric IP followed by some kind of mask */
if (inet_ntop(AF_INET6, a, trad,
sizeof(trad)) == NULL)
bprintf(bp, "Error ntop in print_ip6\n");
bprintf(bp, "%s", trad );
if (mb < 0) /* mask not contiguous */
bprintf(bp, "/%s", inet_ntop(AF_INET6, &a[1],
trad, sizeof(trad)));
else if (mb < 128)
bprintf(bp, "/%d", mb);
}
if (len > 2)
bprintf(bp, ",");
}
}
void
fill_icmp6types(ipfw_insn_icmp6 *cmd, char *av, int cblen)
{
uint8_t type;
CHECK_LENGTH(cblen, F_INSN_SIZE(ipfw_insn_icmp6));
while (*av) {
if (*av == ',')
av++;
type = strtoul(av, &av, 0);
if (*av != ',' && *av != '\0')
errx(EX_DATAERR, "invalid ICMP6 type");
/*
* XXX: shouldn't this be 0xFF? I can't see any reason why
* we shouldn't be able to filter all possiable values
* regardless of the ability of the rest of the kernel to do
* anything useful with them.
*/
if (type > ICMP6_MAXTYPE)
errx(EX_DATAERR, "ICMP6 type out of range");
cmd->d[type / 32] |= ( 1 << (type % 32));
}
cmd->o.opcode = O_ICMP6TYPE;
cmd->o.len |= F_INSN_SIZE(ipfw_insn_icmp6);
}
void
print_icmp6types(struct buf_pr *bp, ipfw_insn_u32 *cmd)
{
int i, j;
char sep= ' ';
bprintf(bp, " icmp6types");
for (i = 0; i < 7; i++)
for (j=0; j < 32; ++j) {
if ( (cmd->d[i] & (1 << (j))) == 0)
continue;
bprintf(bp, "%c%d", sep, (i*32 + j));
sep = ',';
}
}
void
print_flow6id(struct buf_pr *bp, ipfw_insn_u32 *cmd)
{
uint16_t i, limit = cmd->o.arg1;
char sep = ',';
bprintf(bp, " flow-id ");
for( i=0; i < limit; ++i) {
if (i == limit - 1)
sep = ' ';
bprintf(bp, "%d%c", cmd->d[i], sep);
}
}
/* structure and define for the extension header in ipv6 */
static struct _s_x ext6hdrcodes[] = {
{ "frag", EXT_FRAGMENT },
{ "hopopt", EXT_HOPOPTS },
{ "route", EXT_ROUTING },
{ "dstopt", EXT_DSTOPTS },
{ "ah", EXT_AH },
{ "esp", EXT_ESP },
{ "rthdr0", EXT_RTHDR0 },
{ "rthdr2", EXT_RTHDR2 },
{ NULL, 0 }
};
/* fills command for the extension header filtering */
int
fill_ext6hdr( ipfw_insn *cmd, char *av)
{
int tok;
char *s = av;
cmd->arg1 = 0;
while(s) {
av = strsep( &s, ",") ;
tok = match_token(ext6hdrcodes, av);
switch (tok) {
case EXT_FRAGMENT:
cmd->arg1 |= EXT_FRAGMENT;
break;
case EXT_HOPOPTS:
cmd->arg1 |= EXT_HOPOPTS;
break;
case EXT_ROUTING:
cmd->arg1 |= EXT_ROUTING;
break;
case EXT_DSTOPTS:
cmd->arg1 |= EXT_DSTOPTS;
break;
case EXT_AH:
cmd->arg1 |= EXT_AH;
break;
case EXT_ESP:
cmd->arg1 |= EXT_ESP;
break;
case EXT_RTHDR0:
cmd->arg1 |= EXT_RTHDR0;
break;
case EXT_RTHDR2:
cmd->arg1 |= EXT_RTHDR2;
break;
default:
errx(EX_DATAERR,
"invalid option for ipv6 exten header");
break;
}
}
if (cmd->arg1 == 0)
return (0);
cmd->opcode = O_EXT_HDR;
cmd->len |= F_INSN_SIZE(ipfw_insn);
return (1);
}
void
print_ext6hdr(struct buf_pr *bp, ipfw_insn *cmd )
{
char sep = ' ';
bprintf(bp, " extension header:");
if (cmd->arg1 & EXT_FRAGMENT) {
bprintf(bp, "%cfragmentation", sep);
sep = ',';
}
if (cmd->arg1 & EXT_HOPOPTS) {
bprintf(bp, "%chop options", sep);
sep = ',';
}
if (cmd->arg1 & EXT_ROUTING) {
bprintf(bp, "%crouting options", sep);
sep = ',';
}
if (cmd->arg1 & EXT_RTHDR0) {
bprintf(bp, "%crthdr0", sep);
sep = ',';
}
if (cmd->arg1 & EXT_RTHDR2) {
bprintf(bp, "%crthdr2", sep);
sep = ',';
}
if (cmd->arg1 & EXT_DSTOPTS) {
bprintf(bp, "%cdestination options", sep);
sep = ',';
}
if (cmd->arg1 & EXT_AH) {
bprintf(bp, "%cauthentication header", sep);
sep = ',';
}
if (cmd->arg1 & EXT_ESP) {
bprintf(bp, "%cencapsulated security payload", sep);
}
}
/* Try to find ipv6 address by hostname */
static int
lookup_host6 (char *host, struct in6_addr *ip6addr)
{
struct hostent *he;
if (!inet_pton(AF_INET6, host, ip6addr)) {
if ((he = gethostbyname2(host, AF_INET6)) == NULL)
return(-1);
memcpy(ip6addr, he->h_addr_list[0], sizeof( struct in6_addr));
}
return (0);
}
/*
* fill the addr and mask fields in the instruction as appropriate from av.
* Update length as appropriate.
* The following formats are allowed:
* any matches any IP6. Actually returns an empty instruction.
* me returns O_IP6_*_ME
*
* 03f1::234:123:0342 single IP6 address
* 03f1::234:123:0342/24 address/masklen
* 03f1::234:123:0342/ffff::ffff:ffff address/mask
* 03f1::234:123:0342/24,03f1::234:123:0343/ List of address
*
* Set of address (as in ipv6) not supported because ipv6 address
* are typically random past the initial prefix.
* Return 1 on success, 0 on failure.
*/
static int
fill_ip6(ipfw_insn_ip6 *cmd, char *av, int cblen, struct tidx *tstate)
{
int len = 0;
struct in6_addr *d = &(cmd->addr6);
char *oav;
/*
* Needed for multiple address.
* Note d[1] points to struct in6_add r mask6 of cmd
*/
cmd->o.len &= ~F_LEN_MASK; /* zero len */
if (strcmp(av, "any") == 0)
return (1);
if (strcmp(av, "me") == 0) { /* Set the data for "me" opt*/
cmd->o.len |= F_INSN_SIZE(ipfw_insn);
return (1);
}
if (strcmp(av, "me6") == 0) { /* Set the data for "me" opt*/
cmd->o.len |= F_INSN_SIZE(ipfw_insn);
return (1);
}
if (strncmp(av, "table(", 6) == 0) {
fill_table(&cmd->o, av, O_IP_DST_LOOKUP, tstate);
return (1);
}
oav = av = strdup(av);
while (av) {
/*
* After the address we can have '/' indicating a mask,
* or ',' indicating another address follows.
*/
char *p, *q;
int masklen;
char md = '\0';
CHECK_LENGTH(cblen, 1 + len + 2 * F_INSN_SIZE(struct in6_addr));
if ((q = strchr(av, ',')) ) {
*q = '\0';
q++;
}
if ((p = strchr(av, '/')) ) {
md = *p; /* save the separator */
*p = '\0'; /* terminate address string */
p++; /* and skip past it */
}
/* now p points to NULL, mask or next entry */
/* lookup stores address in *d as a side effect */
if (lookup_host6(av, d) != 0) {
/* XXX: failed. Free memory and go */
errx(EX_DATAERR, "bad address \"%s\"", av);
}
/* next, look at the mask, if any */
if (md == '/' && strchr(p, ':')) {
if (!inet_pton(AF_INET6, p, &d[1]))
errx(EX_DATAERR, "bad mask \"%s\"", p);
masklen = contigmask((uint8_t *)&(d[1]), 128);
} else {
masklen = (md == '/') ? atoi(p) : 128;
if (masklen > 128 || masklen < 0)
errx(EX_DATAERR, "bad width \"%s\''", p);
else
n2mask(&d[1], masklen);
}
APPLY_MASK(d, &d[1]) /* mask base address with mask */
av = q;
/* Check this entry */
if (masklen == 0) {
/*
* 'any' turns the entire list into a NOP.
* 'not any' never matches, so it is removed from the
* list unless it is the only item, in which case we
* report an error.
*/
if (cmd->o.len & F_NOT && av == NULL && len == 0)
errx(EX_DATAERR, "not any never matches");
continue;
}
/*
* A single IP can be stored alone
*/
if (masklen == 128 && av == NULL && len == 0) {
len = F_INSN_SIZE(struct in6_addr);
break;
}
/* Update length and pointer to arguments */
len += F_INSN_SIZE(struct in6_addr)*2;
d += 2;
} /* end while */
/*
* Total length of the command, remember that 1 is the size of
* the base command.
*/
if (len + 1 > F_LEN_MASK)
errx(EX_DATAERR, "address list too long");
cmd->o.len |= len+1;
free(oav);
return (1);
}
/*
* fills command for ipv6 flow-id filtering
* note that the 20 bit flow number is stored in a array of u_int32_t
* it's supported lists of flow-id, so in the o.arg1 we store how many
* additional flow-id we want to filter, the basic is 1
*/
void
fill_flow6( ipfw_insn_u32 *cmd, char *av, int cblen)
{
u_int32_t type; /* Current flow number */
u_int16_t nflow = 0; /* Current flow index */
char *s = av;
cmd->d[0] = 0; /* Initializing the base number*/
while (s) {
CHECK_LENGTH(cblen, F_INSN_SIZE(ipfw_insn_u32) + nflow + 1);
av = strsep( &s, ",") ;
type = strtoul(av, &av, 0);
if (*av != ',' && *av != '\0')
errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
if (type > 0xfffff)
errx(EX_DATAERR, "flow number out of range %s", av);
cmd->d[nflow] |= type;
nflow++;
}
if( nflow > 0 ) {
cmd->o.opcode = O_FLOW6ID;
cmd->o.len |= F_INSN_SIZE(ipfw_insn_u32) + nflow;
cmd->o.arg1 = nflow;
}
else {
errx(EX_DATAERR, "invalid ipv6 flow number %s", av);
}
}
ipfw_insn *
add_srcip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
{
fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
if (cmd->opcode == O_IP_DST_SET) /* set */
cmd->opcode = O_IP_SRC_SET;
else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */
cmd->opcode = O_IP_SRC_LOOKUP;
else if (F_LEN(cmd) == 0) { /* any */
} else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */
cmd->opcode = O_IP6_SRC_ME;
} else if (F_LEN(cmd) ==
(F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
/* single IP, no mask*/
cmd->opcode = O_IP6_SRC;
} else { /* addr/mask opt */
cmd->opcode = O_IP6_SRC_MASK;
}
return cmd;
}
ipfw_insn *
add_dstip6(ipfw_insn *cmd, char *av, int cblen, struct tidx *tstate)
{
fill_ip6((ipfw_insn_ip6 *)cmd, av, cblen, tstate);
if (cmd->opcode == O_IP_DST_SET) /* set */
;
else if (cmd->opcode == O_IP_DST_LOOKUP) /* table */
;
else if (F_LEN(cmd) == 0) { /* any */
} else if (F_LEN(cmd) == F_INSN_SIZE(ipfw_insn)) { /* "me" */
cmd->opcode = O_IP6_DST_ME;
} else if (F_LEN(cmd) ==
(F_INSN_SIZE(struct in6_addr) + F_INSN_SIZE(ipfw_insn))) {
/* single IP, no mask*/
cmd->opcode = O_IP6_DST;
} else { /* addr/mask opt */
cmd->opcode = O_IP6_DST_MASK;
}
return cmd;
}