freebsd-dev/lib/libc/net/name6.c
Jilles Tjoelker 7253197882 libc: Use SOCK_CLOEXEC for various internal file descriptors.
This change avoids undesirably passing some internal file descriptors to a
process created (fork+exec) by another thread.

Kernel support for SOCK_CLOEXEC was added in r248534, March 19, 2013.
2013-09-06 21:02:06 +00:00

1115 lines
28 KiB
C

/* $KAME: name6.c,v 1.25 2000/06/26 16:44:40 itojun Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, 1998, and 1999 WIDE Project.
* 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 project 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 PROJECT 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 PROJECT 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.
*/
/*
* ++Copyright++ 1985, 1988, 1993
* -
* Copyright (c) 1985, 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.
* -
* Portions Copyright (c) 1993 by Digital Equipment Corporation.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies, and that
* the name of Digital Equipment Corporation not be used in advertising or
* publicity pertaining to distribution of the document or software without
* specific, written prior permission.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
* WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
* CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
* -
* --Copyright--
*/
/*
* Atsushi Onoe <onoe@sm.sony.co.jp>
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "namespace.h"
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <sys/queue.h>
#include <netinet/in.h>
#ifdef INET6
#include <net/if.h>
#include <net/if_var.h>
#include <sys/sysctl.h>
#include <sys/ioctl.h>
#include <netinet6/in6_var.h> /* XXX */
#endif
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <errno.h>
#include <netdb.h>
#include <resolv.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <nsswitch.h>
#include <unistd.h>
#include "un-namespace.h"
#include "netdb_private.h"
#include "res_private.h"
#ifndef MAXALIASES
#define MAXALIASES 10
#endif
#ifndef MAXADDRS
#define MAXADDRS 20
#endif
#ifndef MAXDNAME
#define MAXDNAME 1025
#endif
#ifdef INET6
#define ADDRLEN(af) ((af) == AF_INET6 ? sizeof(struct in6_addr) : \
sizeof(struct in_addr))
#else
#define ADDRLEN(af) sizeof(struct in_addr)
#endif
#define MAPADDR(ab, ina) \
do { \
memcpy(&(ab)->map_inaddr, ina, sizeof(struct in_addr)); \
memset((ab)->map_zero, 0, sizeof((ab)->map_zero)); \
memset((ab)->map_one, 0xff, sizeof((ab)->map_one)); \
} while (0)
#define MAPADDRENABLED(flags) \
(((flags) & AI_V4MAPPED) || \
(((flags) & AI_V4MAPPED_CFG)))
union inx_addr {
struct in_addr in_addr;
#ifdef INET6
struct in6_addr in6_addr;
#endif
struct {
u_char mau_zero[10];
u_char mau_one[2];
struct in_addr mau_inaddr;
} map_addr_un;
#define map_zero map_addr_un.mau_zero
#define map_one map_addr_un.mau_one
#define map_inaddr map_addr_un.mau_inaddr
};
struct policyqueue {
TAILQ_ENTRY(policyqueue) pc_entry;
#ifdef INET6
struct in6_addrpolicy pc_policy;
#endif
};
TAILQ_HEAD(policyhead, policyqueue);
#define AIO_SRCFLAG_DEPRECATED 0x1
struct hp_order {
union {
struct sockaddr_storage aiou_ss;
struct sockaddr aiou_sa;
} aio_src_un;
#define aio_srcsa aio_src_un.aiou_sa
u_int32_t aio_srcflag;
int aio_srcscope;
int aio_dstscope;
struct policyqueue *aio_srcpolicy;
struct policyqueue *aio_dstpolicy;
union {
struct sockaddr_storage aiou_ss;
struct sockaddr aiou_sa;
} aio_un;
#define aio_sa aio_un.aiou_sa
int aio_matchlen;
char *aio_h_addr;
};
static struct hostent *_hpcopy(struct hostent *, int *);
static struct hostent *_hpaddr(int, const char *, void *, int *);
#ifdef INET6
static struct hostent *_hpmerge(struct hostent *, struct hostent *, int *);
static struct hostent *_hpmapv6(struct hostent *, int *);
#endif
static struct hostent *_hpsort(struct hostent *, res_state);
#ifdef INET6
static struct hostent *_hpreorder(struct hostent *);
static int get_addrselectpolicy(struct policyhead *);
static void free_addrselectpolicy(struct policyhead *);
static struct policyqueue *match_addrselectpolicy(struct sockaddr *,
struct policyhead *);
static void set_source(struct hp_order *, struct policyhead *);
static int matchlen(struct sockaddr *, struct sockaddr *);
static int comp_dst(const void *, const void *);
static int gai_addr2scopetype(struct sockaddr *);
#endif
/*
* Functions defined in RFC2553
* getipnodebyname, getipnodebyaddr, freehostent
*/
struct hostent *
getipnodebyname(const char *name, int af, int flags, int *errp)
{
struct hostent *hp;
union inx_addr addrbuf;
res_state statp;
u_long options;
switch (af) {
case AF_INET:
#ifdef INET6
case AF_INET6:
#endif
break;
default:
*errp = NO_RECOVERY;
return NULL;
}
if (flags & AI_ADDRCONFIG) {
int s;
if ((s = _socket(af, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0)
return NULL;
/*
* TODO:
* Note that implementation dependent test for address
* configuration should be done everytime called
* (or apropriate interval),
* because addresses will be dynamically assigned or deleted.
*/
_close(s);
}
#ifdef INET6
/* special case for literal address */
if (inet_pton(AF_INET6, name, &addrbuf) == 1) {
if (af != AF_INET6) {
*errp = HOST_NOT_FOUND;
return NULL;
}
return _hpaddr(af, name, &addrbuf, errp);
}
#endif
if (inet_aton(name, (struct in_addr *)&addrbuf) == 1) {
if (af != AF_INET) {
if (MAPADDRENABLED(flags)) {
MAPADDR(&addrbuf, &addrbuf.in_addr);
} else {
*errp = HOST_NOT_FOUND;
return NULL;
}
}
return _hpaddr(af, name, &addrbuf, errp);
}
statp = __res_state();
if ((statp->options & RES_INIT) == 0) {
if (res_ninit(statp) < 0) {
*errp = NETDB_INTERNAL;
return NULL;
}
}
options = statp->options;
statp->options &= ~RES_USE_INET6;
hp = gethostbyname2(name, af);
hp = _hpcopy(hp, errp);
#ifdef INET6
if (af == AF_INET6)
hp = _hpreorder(hp);
if (af == AF_INET6 && ((flags & AI_ALL) || hp == NULL) &&
MAPADDRENABLED(flags)) {
struct hostent *hp2 = gethostbyname2(name, AF_INET);
if (hp == NULL)
if (hp2 == NULL)
*errp = statp->res_h_errno;
else
hp = _hpmapv6(hp2, errp);
else {
if (hp2 && strcmp(hp->h_name, hp2->h_name) == 0) {
struct hostent *hpb = hp;
hp = _hpmerge(hpb, hp2, errp);
freehostent(hpb);
}
}
}
#endif
if (hp == NULL)
*errp = statp->res_h_errno;
statp->options = options;
return _hpsort(hp, statp);
}
struct hostent *
getipnodebyaddr(const void *src, size_t len, int af, int *errp)
{
struct hostent *hp;
res_state statp;
u_long options;
#ifdef INET6
struct in6_addr addrbuf;
#else
struct in_addr addrbuf;
#endif
switch (af) {
case AF_INET:
if (len != sizeof(struct in_addr)) {
*errp = NO_RECOVERY;
return NULL;
}
if ((long)src & ~(sizeof(struct in_addr) - 1)) {
memcpy(&addrbuf, src, len);
src = &addrbuf;
}
if (((struct in_addr *)src)->s_addr == 0)
return NULL;
break;
#ifdef INET6
case AF_INET6:
if (len != sizeof(struct in6_addr)) {
*errp = NO_RECOVERY;
return NULL;
}
if ((long)src & ~(sizeof(struct in6_addr) / 2 - 1)) { /*XXX*/
memcpy(&addrbuf, src, len);
src = &addrbuf;
}
if (IN6_IS_ADDR_UNSPECIFIED((struct in6_addr *)src))
return NULL;
if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)src)
|| IN6_IS_ADDR_V4COMPAT((struct in6_addr *)src)) {
src = (char *)src +
(sizeof(struct in6_addr) - sizeof(struct in_addr));
af = AF_INET;
len = sizeof(struct in_addr);
}
break;
#endif
default:
*errp = NO_RECOVERY;
return NULL;
}
statp = __res_state();
if ((statp->options & RES_INIT) == 0) {
if (res_ninit(statp) < 0) {
RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
return NULL;
}
}
options = statp->options;
statp->options &= ~RES_USE_INET6;
hp = gethostbyaddr(src, len, af);
if (hp == NULL)
*errp = statp->res_h_errno;
statp->options = options;
return (_hpcopy(hp, errp));
}
void
freehostent(struct hostent *ptr)
{
free(ptr);
}
/*
* Private utility functions
*/
/*
* _hpcopy: allocate and copy hostent structure
*/
static struct hostent *
_hpcopy(struct hostent *hp, int *errp)
{
struct hostent *nhp;
char *cp, **pp;
int size, addrsize;
int nalias = 0, naddr = 0;
int al_off;
int i;
if (hp == NULL)
return hp;
/* count size to be allocated */
size = sizeof(struct hostent);
if (hp->h_name != NULL)
size += strlen(hp->h_name) + 1;
if ((pp = hp->h_aliases) != NULL) {
for (i = 0; *pp != NULL; i++, pp++) {
if (**pp != '\0') {
size += strlen(*pp) + 1;
nalias++;
}
}
}
/* adjust alignment */
size = ALIGN(size);
al_off = size;
size += sizeof(char *) * (nalias + 1);
addrsize = ALIGN(hp->h_length);
if ((pp = hp->h_addr_list) != NULL) {
while (*pp++ != NULL)
naddr++;
}
size += addrsize * naddr;
size += sizeof(char *) * (naddr + 1);
/* copy */
if ((nhp = (struct hostent *)malloc(size)) == NULL) {
*errp = TRY_AGAIN;
return NULL;
}
cp = (char *)&nhp[1];
if (hp->h_name != NULL) {
nhp->h_name = cp;
strcpy(cp, hp->h_name);
cp += strlen(cp) + 1;
} else
nhp->h_name = NULL;
nhp->h_aliases = (char **)((char *)nhp + al_off);
if ((pp = hp->h_aliases) != NULL) {
for (i = 0; *pp != NULL; pp++) {
if (**pp != '\0') {
nhp->h_aliases[i++] = cp;
strcpy(cp, *pp);
cp += strlen(cp) + 1;
}
}
}
nhp->h_aliases[nalias] = NULL;
cp = (char *)&nhp->h_aliases[nalias + 1];
nhp->h_addrtype = hp->h_addrtype;
nhp->h_length = hp->h_length;
nhp->h_addr_list = (char **)cp;
if ((pp = hp->h_addr_list) != NULL) {
cp = (char *)&nhp->h_addr_list[naddr + 1];
for (i = 0; *pp != NULL; pp++) {
nhp->h_addr_list[i++] = cp;
memcpy(cp, *pp, hp->h_length);
cp += addrsize;
}
}
nhp->h_addr_list[naddr] = NULL;
return nhp;
}
/*
* _hpaddr: construct hostent structure with one address
*/
static struct hostent *
_hpaddr(int af, const char *name, void *addr, int *errp)
{
struct hostent *hp, hpbuf;
char *addrs[2];
hp = &hpbuf;
hp->h_name = (char *)name;
hp->h_aliases = NULL;
hp->h_addrtype = af;
hp->h_length = ADDRLEN(af);
hp->h_addr_list = addrs;
addrs[0] = (char *)addr;
addrs[1] = NULL;
return (_hpcopy(hp, errp));
}
#ifdef INET6
/*
* _hpmerge: merge 2 hostent structure, arguments will be freed
*/
static struct hostent *
_hpmerge(struct hostent *hp1, struct hostent *hp2, int *errp)
{
int i, j;
int naddr, nalias;
char **pp;
struct hostent *hp, hpbuf;
char *aliases[MAXALIASES + 1], *addrs[MAXADDRS + 1];
union inx_addr addrbuf[MAXADDRS];
if (hp1 == NULL)
return _hpcopy(hp2, errp);
if (hp2 == NULL)
return _hpcopy(hp1, errp);
#define HP(i) (i == 1 ? hp1 : hp2)
hp = &hpbuf;
hp->h_name = (hp1->h_name != NULL ? hp1->h_name : hp2->h_name);
hp->h_aliases = aliases;
nalias = 0;
for (i = 1; i <= 2; i++) {
if ((pp = HP(i)->h_aliases) == NULL)
continue;
for (; nalias < MAXALIASES && *pp != NULL; pp++) {
/* check duplicates */
for (j = 0; j < nalias; j++)
if (strcasecmp(*pp, aliases[j]) == 0)
break;
if (j == nalias)
aliases[nalias++] = *pp;
}
}
aliases[nalias] = NULL;
if (hp1->h_length != hp2->h_length) {
hp->h_addrtype = AF_INET6;
hp->h_length = sizeof(struct in6_addr);
} else {
hp->h_addrtype = hp1->h_addrtype;
hp->h_length = hp1->h_length;
}
hp->h_addr_list = addrs;
naddr = 0;
for (i = 1; i <= 2; i++) {
if ((pp = HP(i)->h_addr_list) == NULL)
continue;
if (HP(i)->h_length == hp->h_length) {
while (naddr < MAXADDRS && *pp != NULL)
addrs[naddr++] = *pp++;
} else {
/* copy IPv4 addr as mapped IPv6 addr */
while (naddr < MAXADDRS && *pp != NULL) {
MAPADDR(&addrbuf[naddr], *pp++);
addrs[naddr] = (char *)&addrbuf[naddr];
naddr++;
}
}
}
addrs[naddr] = NULL;
return (_hpcopy(hp, errp));
}
#endif
/*
* _hpmapv6: convert IPv4 hostent into IPv4-mapped IPv6 addresses
*/
#ifdef INET6
static struct hostent *
_hpmapv6(struct hostent *hp, int *errp)
{
struct hostent hp6;
if (hp == NULL)
return NULL;
if (hp->h_addrtype == AF_INET6)
return _hpcopy(hp, errp);
memset(&hp6, 0, sizeof(struct hostent));
hp6.h_addrtype = AF_INET6;
hp6.h_length = sizeof(struct in6_addr);
return _hpmerge(&hp6, hp, errp);
}
#endif
/*
* _hpsort: sort address by sortlist
*/
static struct hostent *
_hpsort(struct hostent *hp, res_state statp)
{
int i, j, n;
u_char *ap, *sp, *mp, **pp;
char t;
char order[MAXADDRS];
int nsort = statp->nsort;
if (hp == NULL || hp->h_addr_list[1] == NULL || nsort == 0)
return hp;
for (i = 0; (ap = (u_char *)hp->h_addr_list[i]); i++) {
for (j = 0; j < nsort; j++) {
#ifdef INET6
if (statp->_u._ext.ext->sort_list[j].af !=
hp->h_addrtype)
continue;
sp = (u_char *)&statp->_u._ext.ext->sort_list[j].addr;
mp = (u_char *)&statp->_u._ext.ext->sort_list[j].mask;
#else
sp = (u_char *)&statp->sort_list[j].addr;
mp = (u_char *)&statp->sort_list[j].mask;
#endif
for (n = 0; n < hp->h_length; n++) {
if ((ap[n] & mp[n]) != sp[n])
break;
}
if (n == hp->h_length)
break;
}
order[i] = j;
}
n = i;
pp = (u_char **)hp->h_addr_list;
for (i = 0; i < n - 1; i++) {
for (j = i + 1; j < n; j++) {
if (order[i] > order[j]) {
ap = pp[i];
pp[i] = pp[j];
pp[j] = ap;
t = order[i];
order[i] = order[j];
order[j] = t;
}
}
}
return hp;
}
#ifdef INET6
/*
* _hpreorder: sort address by default address selection
*/
static struct hostent *
_hpreorder(struct hostent *hp)
{
struct hp_order *aio;
int i, n;
char *ap;
struct sockaddr *sa;
struct policyhead policyhead;
if (hp == NULL)
return hp;
switch (hp->h_addrtype) {
case AF_INET:
#ifdef INET6
case AF_INET6:
#endif
break;
default:
free_addrselectpolicy(&policyhead);
return hp;
}
/* count the number of addrinfo elements for sorting. */
for (n = 0; hp->h_addr_list[n] != NULL; n++)
;
/*
* If the number is small enough, we can skip the reordering process.
*/
if (n <= 1)
return hp;
/* allocate a temporary array for sort and initialization of it. */
if ((aio = malloc(sizeof(*aio) * n)) == NULL)
return hp; /* give up reordering */
memset(aio, 0, sizeof(*aio) * n);
/* retrieve address selection policy from the kernel */
TAILQ_INIT(&policyhead);
if (!get_addrselectpolicy(&policyhead)) {
/* no policy is installed into kernel, we don't sort. */
free(aio);
return hp;
}
for (i = 0; i < n; i++) {
ap = hp->h_addr_list[i];
aio[i].aio_h_addr = ap;
sa = &aio[i].aio_sa;
switch (hp->h_addrtype) {
case AF_INET:
sa->sa_family = AF_INET;
sa->sa_len = sizeof(struct sockaddr_in);
memcpy(&((struct sockaddr_in *)sa)->sin_addr, ap,
sizeof(struct in_addr));
break;
#ifdef INET6
case AF_INET6:
if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) {
sa->sa_family = AF_INET;
sa->sa_len = sizeof(struct sockaddr_in);
memcpy(&((struct sockaddr_in *)sa)->sin_addr,
&ap[12], sizeof(struct in_addr));
} else {
sa->sa_family = AF_INET6;
sa->sa_len = sizeof(struct sockaddr_in6);
memcpy(&((struct sockaddr_in6 *)sa)->sin6_addr,
ap, sizeof(struct in6_addr));
}
break;
#endif
}
aio[i].aio_dstscope = gai_addr2scopetype(sa);
aio[i].aio_dstpolicy = match_addrselectpolicy(sa, &policyhead);
set_source(&aio[i], &policyhead);
}
/* perform sorting. */
qsort(aio, n, sizeof(*aio), comp_dst);
/* reorder the h_addr_list. */
for (i = 0; i < n; i++)
hp->h_addr_list[i] = aio[i].aio_h_addr;
/* cleanup and return */
free(aio);
free_addrselectpolicy(&policyhead);
return hp;
}
static int
get_addrselectpolicy(struct policyhead *head)
{
#ifdef INET6
int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
size_t l;
char *buf;
struct in6_addrpolicy *pol, *ep;
if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0)
return (0);
if ((buf = malloc(l)) == NULL)
return (0);
if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) {
free(buf);
return (0);
}
ep = (struct in6_addrpolicy *)(buf + l);
for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) {
struct policyqueue *new;
if ((new = malloc(sizeof(*new))) == NULL) {
free_addrselectpolicy(head); /* make the list empty */
break;
}
new->pc_policy = *pol;
TAILQ_INSERT_TAIL(head, new, pc_entry);
}
free(buf);
return (1);
#else
return (0);
#endif
}
static void
free_addrselectpolicy(struct policyhead *head)
{
struct policyqueue *ent, *nent;
for (ent = TAILQ_FIRST(head); ent; ent = nent) {
nent = TAILQ_NEXT(ent, pc_entry);
TAILQ_REMOVE(head, ent, pc_entry);
free(ent);
}
}
static struct policyqueue *
match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head)
{
#ifdef INET6
struct policyqueue *ent, *bestent = NULL;
struct in6_addrpolicy *pol;
int matchlen, bestmatchlen = -1;
u_char *mp, *ep, *k, *p, m;
struct sockaddr_in6 key;
switch(addr->sa_family) {
case AF_INET6:
key = *(struct sockaddr_in6 *)addr;
break;
case AF_INET:
/* convert the address into IPv4-mapped IPv6 address. */
memset(&key, 0, sizeof(key));
key.sin6_family = AF_INET6;
key.sin6_len = sizeof(key);
key.sin6_addr.s6_addr[10] = 0xff;
key.sin6_addr.s6_addr[11] = 0xff;
memcpy(&key.sin6_addr.s6_addr[12],
&((struct sockaddr_in *)addr)->sin_addr, 4);
break;
default:
return(NULL);
}
for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) {
pol = &ent->pc_policy;
matchlen = 0;
mp = (u_char *)&pol->addrmask.sin6_addr;
ep = mp + 16; /* XXX: scope field? */
k = (u_char *)&key.sin6_addr;
p = (u_char *)&pol->addr.sin6_addr;
for (; mp < ep && *mp; mp++, k++, p++) {
m = *mp;
if ((*k & m) != *p)
goto next; /* not match */
if (m == 0xff) /* short cut for a typical case */
matchlen += 8;
else {
while (m >= 0x80) {
matchlen++;
m <<= 1;
}
}
}
/* matched. check if this is better than the current best. */
if (matchlen > bestmatchlen) {
bestent = ent;
bestmatchlen = matchlen;
}
next:
continue;
}
return(bestent);
#else
return(NULL);
#endif
}
static void
set_source(struct hp_order *aio, struct policyhead *ph)
{
struct sockaddr_storage ss = aio->aio_un.aiou_ss;
socklen_t srclen;
int s;
/* set unspec ("no source is available"), just in case */
aio->aio_srcsa.sa_family = AF_UNSPEC;
aio->aio_srcscope = -1;
switch(ss.ss_family) {
case AF_INET:
((struct sockaddr_in *)&ss)->sin_port = htons(1);
break;
#ifdef INET6
case AF_INET6:
((struct sockaddr_in6 *)&ss)->sin6_port = htons(1);
break;
#endif
default: /* ignore unsupported AFs explicitly */
return;
}
/* open a socket to get the source address for the given dst */
if ((s = _socket(ss.ss_family, SOCK_DGRAM | SOCK_CLOEXEC,
IPPROTO_UDP)) < 0)
return; /* give up */
if (_connect(s, (struct sockaddr *)&ss, ss.ss_len) < 0)
goto cleanup;
srclen = ss.ss_len;
if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) {
aio->aio_srcsa.sa_family = AF_UNSPEC;
goto cleanup;
}
aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa);
aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph);
aio->aio_matchlen = matchlen(&aio->aio_srcsa, (struct sockaddr *)&ss);
#ifdef INET6
if (ss.ss_family == AF_INET6) {
struct in6_ifreq ifr6;
u_int32_t flags6;
memset(&ifr6, 0, sizeof(ifr6));
memcpy(&ifr6.ifr_addr, &ss, ss.ss_len);
if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) {
flags6 = ifr6.ifr_ifru.ifru_flags6;
if ((flags6 & IN6_IFF_DEPRECATED))
aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED;
}
}
#endif
cleanup:
_close(s);
return;
}
static int
matchlen(struct sockaddr *src, struct sockaddr *dst)
{
int match = 0;
u_char *s, *d;
u_char *lim, r;
int addrlen;
switch (src->sa_family) {
#ifdef INET6
case AF_INET6:
s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr;
d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr;
addrlen = sizeof(struct in6_addr);
lim = s + addrlen;
break;
#endif
case AF_INET:
s = (u_char *)&((struct sockaddr_in *)src)->sin_addr;
d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr;
addrlen = sizeof(struct in_addr);
lim = s + addrlen;
break;
default:
return(0);
}
while (s < lim)
if ((r = (*d++ ^ *s++)) != 0) {
while (r < addrlen * 8) {
match++;
r <<= 1;
}
break;
} else
match += 8;
return(match);
}
static int
comp_dst(const void *arg1, const void *arg2)
{
const struct hp_order *dst1 = arg1, *dst2 = arg2;
/*
* Rule 1: Avoid unusable destinations.
* XXX: we currently do not consider if an appropriate route exists.
*/
if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
dst2->aio_srcsa.sa_family == AF_UNSPEC) {
return(-1);
}
if (dst1->aio_srcsa.sa_family == AF_UNSPEC &&
dst2->aio_srcsa.sa_family != AF_UNSPEC) {
return(1);
}
/* Rule 2: Prefer matching scope. */
if (dst1->aio_dstscope == dst1->aio_srcscope &&
dst2->aio_dstscope != dst2->aio_srcscope) {
return(-1);
}
if (dst1->aio_dstscope != dst1->aio_srcscope &&
dst2->aio_dstscope == dst2->aio_srcscope) {
return(1);
}
/* Rule 3: Avoid deprecated addresses. */
if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
dst2->aio_srcsa.sa_family != AF_UNSPEC) {
if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
return(-1);
}
if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
!(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
return(1);
}
}
/* Rule 4: Prefer home addresses. */
/* XXX: not implemented yet */
/* Rule 5: Prefer matching label. */
#ifdef INET6
if (dst1->aio_srcpolicy && dst1->aio_dstpolicy &&
dst1->aio_srcpolicy->pc_policy.label ==
dst1->aio_dstpolicy->pc_policy.label &&
(dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL ||
dst2->aio_srcpolicy->pc_policy.label !=
dst2->aio_dstpolicy->pc_policy.label)) {
return(-1);
}
if (dst2->aio_srcpolicy && dst2->aio_dstpolicy &&
dst2->aio_srcpolicy->pc_policy.label ==
dst2->aio_dstpolicy->pc_policy.label &&
(dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL ||
dst1->aio_srcpolicy->pc_policy.label !=
dst1->aio_dstpolicy->pc_policy.label)) {
return(1);
}
#endif
/* Rule 6: Prefer higher precedence. */
#ifdef INET6
if (dst1->aio_dstpolicy &&
(dst2->aio_dstpolicy == NULL ||
dst1->aio_dstpolicy->pc_policy.preced >
dst2->aio_dstpolicy->pc_policy.preced)) {
return(-1);
}
if (dst2->aio_dstpolicy &&
(dst1->aio_dstpolicy == NULL ||
dst2->aio_dstpolicy->pc_policy.preced >
dst1->aio_dstpolicy->pc_policy.preced)) {
return(1);
}
#endif
/* Rule 7: Prefer native transport. */
/* XXX: not implemented yet */
/* Rule 8: Prefer smaller scope. */
if (dst1->aio_dstscope >= 0 &&
dst1->aio_dstscope < dst2->aio_dstscope) {
return(-1);
}
if (dst2->aio_dstscope >= 0 &&
dst2->aio_dstscope < dst1->aio_dstscope) {
return(1);
}
/*
* Rule 9: Use longest matching prefix.
* We compare the match length in a same AF only.
*/
if (dst1->aio_sa.sa_family == dst2->aio_sa.sa_family) {
if (dst1->aio_matchlen > dst2->aio_matchlen) {
return(-1);
}
if (dst1->aio_matchlen < dst2->aio_matchlen) {
return(1);
}
}
/* Rule 10: Otherwise, leave the order unchanged. */
return(-1);
}
/*
* Copy from scope.c.
* XXX: we should standardize the functions and link them as standard
* library.
*/
static int
gai_addr2scopetype(struct sockaddr *sa)
{
#ifdef INET6
struct sockaddr_in6 *sa6;
#endif
struct sockaddr_in *sa4;
switch(sa->sa_family) {
#ifdef INET6
case AF_INET6:
sa6 = (struct sockaddr_in6 *)sa;
if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
/* just use the scope field of the multicast address */
return(sa6->sin6_addr.s6_addr[2] & 0x0f);
}
/*
* Unicast addresses: map scope type to corresponding scope
* value defined for multcast addresses.
* XXX: hardcoded scope type values are bad...
*/
if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr))
return(1); /* node local scope */
if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr))
return(2); /* link-local scope */
if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr))
return(5); /* site-local scope */
return(14); /* global scope */
break;
#endif
case AF_INET:
/*
* IPv4 pseudo scoping according to RFC 3484.
*/
sa4 = (struct sockaddr_in *)sa;
/* IPv4 autoconfiguration addresses have link-local scope. */
if (((u_char *)&sa4->sin_addr)[0] == 169 &&
((u_char *)&sa4->sin_addr)[1] == 254)
return(2);
/* Private addresses have site-local scope. */
if (((u_char *)&sa4->sin_addr)[0] == 10 ||
(((u_char *)&sa4->sin_addr)[0] == 172 &&
(((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) ||
(((u_char *)&sa4->sin_addr)[0] == 192 &&
((u_char *)&sa4->sin_addr)[1] == 168))
return(14); /* XXX: It should be 5 unless NAT */
/* Loopback addresses have link-local scope. */
if (((u_char *)&sa4->sin_addr)[0] == 127)
return(2);
return(14);
break;
default:
errno = EAFNOSUPPORT; /* is this a good error? */
return(-1);
}
}
#endif