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in_selsrc.c revision 1.8.12.2
      1  1.8.12.2      yamt /*	$NetBSD: in_selsrc.c,v 1.8.12.2 2014/05/22 11:41:09 yamt Exp $	*/
      2       1.1    dyoung 
      3       1.1    dyoung /*-
      4       1.1    dyoung  * Copyright (c) 2005 David Young.  All rights reserved.
      5       1.1    dyoung  *
      6       1.1    dyoung  * This code was written by David Young.
      7       1.1    dyoung  *
      8       1.1    dyoung  * Redistribution and use in source and binary forms, with or without
      9       1.1    dyoung  * modification, are permitted provided that the following conditions
     10       1.1    dyoung  * are met:
     11       1.1    dyoung  * 1. Redistributions of source code must retain the above copyright
     12       1.1    dyoung  *    notice, this list of conditions and the following disclaimer.
     13       1.1    dyoung  * 2. Redistributions in binary form must reproduce the above copyright
     14       1.1    dyoung  *    notice, this list of conditions and the following disclaimer in the
     15       1.1    dyoung  *    documentation and/or other materials provided with the distribution.
     16       1.1    dyoung  *
     17       1.1    dyoung  * THIS SOFTWARE IS PROVIDED BY DAVID YOUNG ``AS IS'' AND ANY
     18       1.1    dyoung  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
     19       1.1    dyoung  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
     20       1.1    dyoung  * PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
     21       1.1    dyoung  * FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
     22       1.1    dyoung  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     23       1.1    dyoung  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     24       1.1    dyoung  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     25       1.1    dyoung  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
     26       1.1    dyoung  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     27       1.1    dyoung  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     28       1.1    dyoung  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29       1.1    dyoung  */
     30       1.1    dyoung 
     31       1.1    dyoung #include <sys/cdefs.h>
     32  1.8.12.2      yamt __KERNEL_RCSID(0, "$NetBSD: in_selsrc.c,v 1.8.12.2 2014/05/22 11:41:09 yamt Exp $");
     33       1.1    dyoung 
     34       1.1    dyoung #include "opt_inet.h"
     35       1.1    dyoung #include "opt_inet_conf.h"
     36       1.1    dyoung 
     37       1.1    dyoung #include <lib/libkern/libkern.h>
     38       1.1    dyoung 
     39       1.1    dyoung #include <sys/param.h>
     40       1.1    dyoung #include <sys/ioctl.h>
     41       1.1    dyoung #include <sys/errno.h>
     42       1.1    dyoung #include <sys/malloc.h>
     43       1.1    dyoung #include <sys/socket.h>
     44       1.1    dyoung #include <sys/socketvar.h>
     45       1.1    dyoung #include <sys/sysctl.h>
     46       1.1    dyoung #include <sys/systm.h>
     47       1.1    dyoung #include <sys/proc.h>
     48       1.1    dyoung #include <sys/syslog.h>
     49       1.1    dyoung 
     50       1.1    dyoung #include <net/if.h>
     51       1.1    dyoung 
     52       1.1    dyoung #include <net/if_ether.h>
     53       1.1    dyoung 
     54       1.1    dyoung #include <netinet/in_systm.h>
     55       1.1    dyoung #include <netinet/in.h>
     56       1.1    dyoung #include <netinet/in_var.h>
     57       1.1    dyoung #include <netinet/ip.h>
     58       1.1    dyoung #include <netinet/ip_var.h>
     59       1.1    dyoung #include <netinet/in_ifattach.h>
     60       1.1    dyoung #include <netinet/in_pcb.h>
     61       1.1    dyoung #include <netinet/if_inarp.h>
     62       1.1    dyoung #include <netinet/ip_mroute.h>
     63       1.1    dyoung #include <netinet/igmp_var.h>
     64       1.1    dyoung #include <netinet/in_selsrc.h>
     65       1.1    dyoung 
     66       1.1    dyoung #ifdef INET
     67       1.1    dyoung struct score_src_name {
     68       1.1    dyoung 	const char		*sn_name;
     69       1.1    dyoung 	const in_score_src_t	sn_score_src;
     70       1.1    dyoung };
     71       1.1    dyoung 
     72       1.1    dyoung static const struct sysctlnode *in_domifattach_sysctl(struct in_ifsysctl *);
     73       1.1    dyoung static int in_preference(const struct in_addr *, int, int,
     74       1.1    dyoung     const struct in_addr *);
     75       1.1    dyoung static int in_index(const struct in_addr *, int, int, const struct in_addr *);
     76       1.1    dyoung static int in_matchlen(const struct in_addr *, int, int,
     77       1.1    dyoung     const struct in_addr *);
     78       1.1    dyoung static int in_match_category(const struct in_addr *, int, int,
     79       1.1    dyoung     const struct in_addr *);
     80       1.1    dyoung static size_t in_get_selectsrc(const struct in_ifselsrc *, char *,
     81       1.1    dyoung     const size_t);
     82       1.1    dyoung static int in_set_selectsrc(struct in_ifselsrc *, char *buf);
     83       1.1    dyoung static int in_sysctl_selectsrc(SYSCTLFN_PROTO);
     84       1.1    dyoung static in_score_src_t name_to_score_src(const char *);
     85       1.1    dyoung static const char *score_src_to_name(const in_score_src_t);
     86       1.1    dyoung static void in_score(const in_score_src_t *, int *, int *,
     87       1.1    dyoung     const struct in_addr *, int, int, const struct in_addr *);
     88       1.1    dyoung 
     89       1.1    dyoung static const struct score_src_name score_src_names[] = {
     90       1.1    dyoung 	  {"same-category", in_match_category}
     91       1.1    dyoung 	, {"common-prefix-len", in_matchlen}
     92       1.1    dyoung 	, {"index", in_index}
     93       1.1    dyoung 	, {"preference", in_preference}
     94       1.1    dyoung 	, {NULL, NULL}
     95       1.1    dyoung };
     96       1.1    dyoung 
     97       1.1    dyoung static const struct in_ifselsrc initial_iss = { 0, {NULL} };
     98       1.1    dyoung 
     99       1.1    dyoung static struct in_ifselsrc default_iss = { 0, {in_index} };
    100       1.1    dyoung 
    101       1.1    dyoung #ifdef GETIFA_DEBUG
    102       1.1    dyoung int in_selsrc_debug = 0;
    103       1.4    dyoung #endif /* GETIFA_DEBUG */
    104       1.1    dyoung 
    105       1.1    dyoung SYSCTL_SETUP(sysctl_selectsrc_setup, "sysctl selectsrc subtree setup")
    106       1.1    dyoung {
    107       1.1    dyoung 	int rc;
    108       1.1    dyoung 	const struct sysctlnode *rnode, *cnode;
    109       1.1    dyoung 
    110       1.1    dyoung 	if ((rc = sysctl_createv(clog, 0, NULL, &rnode,
    111       1.1    dyoung 	    CTLFLAG_PERMANENT, CTLTYPE_NODE, "inet",
    112       1.1    dyoung 	    NULL, NULL, 0, NULL, 0, CTL_NET, PF_INET, CTL_EOL)) != 0) {
    113       1.1    dyoung 		printf("%s: could not create net.inet, rc = %d\n", __func__,
    114       1.1    dyoung 		    rc);
    115       1.1    dyoung 		return;
    116       1.1    dyoung 	}
    117       1.1    dyoung 	if ((rc = sysctl_createv(clog, 0, NULL, &rnode,
    118       1.1    dyoung 	    CTLFLAG_PERMANENT, CTLTYPE_NODE, "ip",
    119       1.1    dyoung 	    NULL, NULL, 0, NULL, 0,
    120       1.1    dyoung 	    CTL_NET, PF_INET, IPPROTO_IP, CTL_EOL)) != 0) {
    121       1.1    dyoung 		printf("%s: could not create net.inet.ip, rc = %d\n", __func__,
    122       1.1    dyoung 		    rc);
    123       1.1    dyoung 		return;
    124       1.1    dyoung 	}
    125       1.1    dyoung 	if ((rc = sysctl_createv(clog, 0, NULL, &rnode,
    126       1.1    dyoung 	    CTLFLAG_PERMANENT, CTLTYPE_NODE, "selectsrc",
    127       1.1    dyoung 	    NULL, NULL, 0, NULL, 0,
    128       1.1    dyoung 	    CTL_NET, PF_INET, IPPROTO_IP, CTL_CREATE, CTL_EOL)) != 0) {
    129       1.1    dyoung 		printf("%s: could not create net.inet.ip.selectsrc, "
    130       1.1    dyoung 		       "rc = %d\n", __func__, rc);
    131       1.1    dyoung 		return;
    132       1.1    dyoung 	}
    133       1.4    dyoung #ifdef GETIFA_DEBUG
    134       1.1    dyoung 	if ((rc = sysctl_createv(clog, 0, &rnode, &cnode,
    135       1.1    dyoung 	    CTLFLAG_PERMANENT|CTLFLAG_READWRITE, CTLTYPE_INT, "debug",
    136       1.1    dyoung 	    SYSCTL_DESCR("enable source-selection debug messages"),
    137       1.1    dyoung 	    NULL, 0, &in_selsrc_debug, 0, CTL_CREATE, CTL_EOL)) != 0) {
    138       1.1    dyoung 		printf("%s: could not create net.inet.ip.selectsrc.debug, "
    139       1.1    dyoung 		       "rc = %d\n", __func__, rc);
    140       1.1    dyoung 		return;
    141       1.1    dyoung 	}
    142       1.4    dyoung #endif /* GETIFA_DEBUG */
    143       1.1    dyoung 	if ((rc = sysctl_createv(clog, 0, &rnode, &cnode,
    144  1.8.12.2      yamt 	    CTLFLAG_READWRITE, CTLTYPE_STRUCT, "default",
    145       1.1    dyoung 	    SYSCTL_DESCR("default source selection policy"),
    146       1.1    dyoung 	    in_sysctl_selectsrc, 0, &default_iss, IN_SELECTSRC_LEN,
    147       1.1    dyoung 	    CTL_CREATE, CTL_EOL)) != 0) {
    148       1.1    dyoung 		printf(
    149       1.1    dyoung 		    "%s: could not create net.inet.ip.selectsrc.default (%d)\n",
    150       1.1    dyoung 		    __func__, rc);
    151       1.1    dyoung 		return;
    152       1.1    dyoung 	}
    153       1.1    dyoung }
    154       1.1    dyoung 
    155       1.1    dyoung /*
    156       1.5    dyoung  * Score by address preference: prefer addresses with higher preference
    157       1.1    dyoung  * number.  Preference numbers are assigned with ioctl SIOCSIFADDRPREF.
    158       1.1    dyoung  */
    159       1.1    dyoung static int
    160       1.3  christos in_preference(const struct in_addr *src, int preference,
    161       1.3  christos     int idx, const struct in_addr *dst)
    162       1.1    dyoung {
    163       1.5    dyoung 	return preference;
    164       1.1    dyoung }
    165       1.1    dyoung 
    166       1.1    dyoung /*
    167       1.1    dyoung  * Score by address "index": prefer addresses nearer the head of
    168       1.1    dyoung  * the ifaddr list.
    169       1.1    dyoung  */
    170       1.1    dyoung static int
    171       1.3  christos in_index(const struct in_addr *src, int preference, int idx,
    172       1.3  christos     const struct in_addr *dst)
    173       1.1    dyoung {
    174       1.1    dyoung 	return -idx;
    175       1.1    dyoung }
    176       1.1    dyoung 
    177       1.1    dyoung /*
    178       1.1    dyoung  * Length of longest common prefix of src and dst.
    179       1.1    dyoung  *
    180       1.1    dyoung  * (Derived from in6_matchlen.)
    181       1.1    dyoung  */
    182       1.1    dyoung static int
    183       1.3  christos in_matchlen(const struct in_addr *src, int preference,
    184       1.3  christos     int idx, const struct in_addr *dst)
    185       1.1    dyoung {
    186       1.1    dyoung 	int match = 0;
    187       1.1    dyoung 	const uint8_t *s = (const uint8_t *)src, *d = (const uint8_t *)dst;
    188       1.1    dyoung 	const uint8_t *lim = s + 4;
    189       1.1    dyoung 	uint_fast8_t r = 0;
    190       1.1    dyoung 
    191       1.1    dyoung 	while (s < lim && (r = (*d++ ^ *s++)) == 0)
    192       1.1    dyoung 		match += 8;
    193       1.1    dyoung 
    194       1.1    dyoung 	if (s == lim)
    195       1.1    dyoung 		return match;
    196       1.1    dyoung 
    197       1.1    dyoung 	while ((r & 0x80) == 0) {
    198       1.1    dyoung 		match++;
    199       1.1    dyoung 		r <<= 1;
    200       1.1    dyoung 	}
    201       1.1    dyoung 	return match;
    202       1.1    dyoung }
    203       1.1    dyoung 
    204       1.1    dyoung static enum in_category
    205       1.1    dyoung in_categorize(const struct in_addr *s)
    206       1.1    dyoung {
    207       1.1    dyoung 	if (IN_ANY_LOCAL(s->s_addr))
    208       1.1    dyoung 		return IN_CATEGORY_LINKLOCAL;
    209       1.1    dyoung 	else if (IN_PRIVATE(s->s_addr))
    210       1.1    dyoung 		return IN_CATEGORY_PRIVATE;
    211       1.1    dyoung 	else
    212       1.1    dyoung 		return IN_CATEGORY_OTHER;
    213       1.1    dyoung }
    214       1.1    dyoung 
    215       1.1    dyoung static int
    216       1.3  christos in_match_category(const struct in_addr *src, int preference,
    217       1.3  christos     int idx, const struct in_addr *dst)
    218       1.1    dyoung {
    219       1.1    dyoung 	enum in_category dst_c = in_categorize(dst),
    220       1.1    dyoung 	                 src_c = in_categorize(src);
    221       1.1    dyoung #ifdef GETIFA_DEBUG
    222       1.1    dyoung 	if (in_selsrc_debug) {
    223       1.1    dyoung 		printf("%s: dst %#08" PRIx32 " categ %d, src %#08" PRIx32
    224       1.1    dyoung 		    " categ %d\n", __func__, ntohl(dst->s_addr), dst_c,
    225       1.1    dyoung 		    ntohl(src->s_addr), src_c);
    226       1.1    dyoung 	}
    227       1.1    dyoung #endif /* GETIFA_DEBUG */
    228       1.1    dyoung 
    229       1.1    dyoung 	if (dst_c == src_c)
    230       1.1    dyoung 		return 2;
    231       1.1    dyoung 	else if (dst_c == IN_CATEGORY_LINKLOCAL && src_c == IN_CATEGORY_PRIVATE)
    232       1.1    dyoung 		return 1;
    233       1.1    dyoung 	else if (dst_c == IN_CATEGORY_PRIVATE && src_c == IN_CATEGORY_LINKLOCAL)
    234       1.1    dyoung 		return 1;
    235       1.1    dyoung 	else if (dst_c == IN_CATEGORY_OTHER && src_c == IN_CATEGORY_PRIVATE)
    236       1.1    dyoung 		return 1;
    237       1.1    dyoung 	else
    238       1.1    dyoung 		return 0;
    239       1.1    dyoung }
    240       1.1    dyoung 
    241       1.1    dyoung static void
    242       1.1    dyoung in_score(const in_score_src_t *score_src, int *score, int *scorelenp,
    243       1.1    dyoung     const struct in_addr *src, int preference, int idx,
    244       1.1    dyoung     const struct in_addr *dst)
    245       1.1    dyoung {
    246       1.1    dyoung 	int i;
    247       1.1    dyoung 
    248       1.1    dyoung 	for (i = 0; i < IN_SCORE_SRC_MAX && score_src[i] != NULL; i++)
    249       1.1    dyoung 		score[i] = (*score_src[i])(src, preference, idx, dst);
    250       1.1    dyoung 	if (scorelenp != NULL)
    251       1.1    dyoung 		*scorelenp = i;
    252       1.1    dyoung }
    253       1.1    dyoung 
    254       1.1    dyoung static int
    255       1.1    dyoung in_score_cmp(int *score1, int *score2, int scorelen)
    256       1.1    dyoung {
    257       1.1    dyoung 	int i;
    258       1.1    dyoung 
    259       1.1    dyoung 	for (i = 0; i < scorelen; i++) {
    260       1.1    dyoung 		if (score1[i] == score2[i])
    261       1.1    dyoung 			continue;
    262       1.1    dyoung 		return score1[i] - score2[i];
    263       1.1    dyoung 	}
    264       1.1    dyoung 	return 0;
    265       1.1    dyoung }
    266       1.1    dyoung 
    267       1.1    dyoung #ifdef GETIFA_DEBUG
    268       1.1    dyoung static void
    269       1.1    dyoung in_score_println(int *score, int scorelen)
    270       1.1    dyoung {
    271       1.1    dyoung 	int i;
    272       1.1    dyoung 	const char *delim = "[";
    273       1.1    dyoung 
    274       1.1    dyoung 	for (i = 0; i < scorelen; i++) {
    275       1.1    dyoung 		printf("%s%d", delim, score[i]);
    276       1.1    dyoung 		delim = ", ";
    277       1.1    dyoung 	}
    278       1.1    dyoung 	printf("]\n");
    279       1.1    dyoung }
    280       1.1    dyoung #endif /* GETIFA_DEBUG */
    281       1.1    dyoung 
    282       1.1    dyoung /* Scan the interface addresses on the interface ifa->ifa_ifp for
    283       1.1    dyoung  * the source address that best matches the destination, dst0,
    284       1.1    dyoung  * according to the source address-selection policy for this
    285       1.1    dyoung  * interface.  If there is no better match than `ifa', return `ifa'.
    286       1.1    dyoung  * Otherwise, return the best address.
    287       1.1    dyoung  *
    288       1.1    dyoung  * Note that in_getifa is called after the kernel has decided which
    289       1.1    dyoung  * output interface to use (ifa->ifa_ifp), and in_getifa will not
    290       1.1    dyoung  * scan an address belonging to any other interface.
    291       1.1    dyoung  */
    292       1.1    dyoung struct ifaddr *
    293       1.1    dyoung in_getifa(struct ifaddr *ifa, const struct sockaddr *dst0)
    294       1.1    dyoung {
    295       1.1    dyoung 	const in_score_src_t *score_src;
    296       1.1    dyoung 	int idx, scorelen;
    297       1.1    dyoung 	const struct sockaddr_in *dst, *src;
    298       1.1    dyoung 	struct ifaddr *alt_ifa, *best_ifa;
    299       1.1    dyoung 	struct ifnet *ifp;
    300       1.1    dyoung 	struct in_ifsysctl *isc;
    301       1.1    dyoung 	struct in_ifselsrc *iss;
    302       1.1    dyoung 	int best_score[IN_SCORE_SRC_MAX], score[IN_SCORE_SRC_MAX];
    303       1.1    dyoung 
    304       1.1    dyoung 	if (ifa->ifa_addr->sa_family != AF_INET ||
    305       1.1    dyoung 	    dst0 == NULL || dst0->sa_family != AF_INET) {	/* Possible. */
    306       1.1    dyoung 		ifa->ifa_seqno = NULL;
    307       1.1    dyoung 		return ifa;
    308       1.1    dyoung 	}
    309       1.1    dyoung 
    310       1.1    dyoung 	ifp = ifa->ifa_ifp;
    311       1.1    dyoung 	isc = (struct in_ifsysctl *)ifp->if_afdata[AF_INET];
    312       1.1    dyoung 	if (isc != NULL && isc->isc_selsrc != NULL &&
    313       1.1    dyoung 	    isc->isc_selsrc->iss_score_src[0] != NULL)
    314       1.1    dyoung 		iss = isc->isc_selsrc;
    315       1.1    dyoung 	else
    316       1.1    dyoung 		iss = &default_iss;
    317       1.1    dyoung 	score_src = &iss->iss_score_src[0];
    318       1.1    dyoung 
    319       1.1    dyoung 	dst = (const struct sockaddr_in *)dst0;
    320       1.1    dyoung 
    321       1.1    dyoung 	best_ifa = ifa;
    322       1.1    dyoung 
    323       1.1    dyoung 	/* Find out the index of this ifaddr. */
    324       1.1    dyoung 	idx = 0;
    325       1.6    dyoung 	IFADDR_FOREACH(alt_ifa, ifa->ifa_ifp) {
    326       1.1    dyoung 		if (alt_ifa == best_ifa)
    327       1.1    dyoung 			break;
    328       1.1    dyoung 		idx++;
    329       1.1    dyoung 	}
    330       1.1    dyoung 	in_score(score_src, best_score, &scorelen, &IA_SIN(best_ifa)->sin_addr,
    331       1.1    dyoung 	    best_ifa->ifa_preference, idx, &dst->sin_addr);
    332       1.1    dyoung 
    333       1.1    dyoung #ifdef GETIFA_DEBUG
    334       1.1    dyoung 	if (in_selsrc_debug) {
    335       1.1    dyoung 		printf("%s: enter dst %#" PRIx32 " src %#" PRIx32 " score ",
    336       1.1    dyoung 		    __func__, ntohl(dst->sin_addr.s_addr),
    337       1.1    dyoung 		    ntohl(satosin(best_ifa->ifa_addr)->sin_addr.s_addr));
    338       1.1    dyoung 		in_score_println(best_score, scorelen);
    339       1.1    dyoung 	}
    340       1.1    dyoung #endif /* GETIFA_DEBUG */
    341       1.1    dyoung 
    342       1.1    dyoung 	idx = -1;
    343       1.6    dyoung 	IFADDR_FOREACH(alt_ifa, ifa->ifa_ifp) {
    344       1.1    dyoung 		++idx;
    345       1.1    dyoung 		src = IA_SIN(alt_ifa);
    346       1.1    dyoung 
    347       1.1    dyoung 		if (alt_ifa == ifa || src->sin_family != AF_INET)
    348       1.1    dyoung 			continue;
    349       1.1    dyoung 
    350       1.1    dyoung 		in_score(score_src, score, NULL, &src->sin_addr,
    351       1.1    dyoung 		         alt_ifa->ifa_preference, idx, &dst->sin_addr);
    352       1.1    dyoung 
    353       1.1    dyoung #ifdef GETIFA_DEBUG
    354       1.1    dyoung 		if (in_selsrc_debug) {
    355       1.1    dyoung 			printf("%s: src %#" PRIx32 " score ", __func__,
    356       1.1    dyoung 			    ntohl(src->sin_addr.s_addr));
    357       1.1    dyoung 			in_score_println(score, scorelen);
    358       1.1    dyoung 		}
    359       1.1    dyoung #endif /* GETIFA_DEBUG */
    360       1.1    dyoung 
    361       1.1    dyoung 		if (in_score_cmp(score, best_score, scorelen) > 0) {
    362       1.1    dyoung 			(void)memcpy(best_score, score, sizeof(best_score));
    363       1.1    dyoung 			best_ifa = alt_ifa;
    364       1.1    dyoung 		}
    365       1.1    dyoung 	}
    366       1.1    dyoung #ifdef GETIFA_DEBUG
    367       1.1    dyoung 	if (in_selsrc_debug) {
    368       1.1    dyoung 		printf("%s: choose src %#" PRIx32 " score ", __func__,
    369       1.1    dyoung 		    ntohl(IA_SIN(best_ifa)->sin_addr.s_addr));
    370       1.1    dyoung 		in_score_println(best_score, scorelen);
    371       1.1    dyoung 	}
    372       1.1    dyoung #endif /* GETIFA_DEBUG */
    373       1.1    dyoung 
    374       1.1    dyoung 	best_ifa->ifa_seqno = &iss->iss_seqno;
    375       1.1    dyoung 	return best_ifa;
    376       1.1    dyoung }
    377       1.1    dyoung 
    378       1.1    dyoung static in_score_src_t
    379       1.1    dyoung name_to_score_src(const char *name)
    380       1.1    dyoung {
    381       1.1    dyoung 	int i;
    382       1.1    dyoung 
    383       1.1    dyoung 	for (i = 0; score_src_names[i].sn_name != NULL; i++) {
    384       1.1    dyoung 		if (strcmp(score_src_names[i].sn_name, name) == 0)
    385       1.1    dyoung 			return score_src_names[i].sn_score_src;
    386       1.1    dyoung 	}
    387       1.1    dyoung 	return NULL;
    388       1.1    dyoung }
    389       1.1    dyoung 
    390       1.1    dyoung static const char *
    391       1.1    dyoung score_src_to_name(const in_score_src_t score_src)
    392       1.1    dyoung {
    393       1.1    dyoung 	int i;
    394       1.1    dyoung 	for (i = 0; score_src_names[i].sn_name != NULL; i++) {
    395       1.1    dyoung 		if (score_src == score_src_names[i].sn_score_src)
    396       1.1    dyoung 			return score_src_names[i].sn_name;
    397       1.1    dyoung 	}
    398       1.1    dyoung 	return "<unknown>";
    399       1.1    dyoung }
    400       1.1    dyoung 
    401       1.1    dyoung static size_t
    402       1.1    dyoung in_get_selectsrc(const struct in_ifselsrc *iss, char *buf0,
    403       1.1    dyoung     const size_t buflen0)
    404       1.1    dyoung {
    405       1.1    dyoung 	int i, rc;
    406       1.1    dyoung 	char *buf = buf0;
    407       1.1    dyoung 	const char *delim;
    408       1.1    dyoung 	size_t buflen = buflen0;
    409       1.1    dyoung 
    410       1.1    dyoung 	KASSERT(buflen >= 1);
    411       1.1    dyoung 
    412       1.1    dyoung 	for (delim = "", i = 0;
    413       1.1    dyoung 	     i < IN_SCORE_SRC_MAX && iss->iss_score_src[i] != NULL;
    414       1.1    dyoung 	     delim = ",", i++) {
    415       1.1    dyoung 		rc = snprintf(buf, buflen, "%s%s",
    416       1.1    dyoung 		    delim, score_src_to_name(iss->iss_score_src[i]));
    417       1.1    dyoung 		if (rc == -1)
    418       1.1    dyoung 			return buflen0 - buflen;
    419       1.1    dyoung 		if (rc >= buflen)
    420       1.1    dyoung 			return buflen0 + rc - buflen;
    421       1.1    dyoung 		buf += rc;
    422       1.1    dyoung 		buflen -= rc;
    423       1.1    dyoung 	}
    424       1.1    dyoung 	if (buf == buf0)
    425       1.1    dyoung 		*buf++ = '\0';
    426       1.1    dyoung 	return buf - buf0;
    427       1.1    dyoung }
    428       1.1    dyoung 
    429       1.1    dyoung static int
    430       1.1    dyoung in_set_selectsrc(struct in_ifselsrc *iss, char *buf)
    431       1.1    dyoung {
    432       1.1    dyoung 	int i, s;
    433       1.1    dyoung 	char *next = buf;
    434       1.1    dyoung 	const char *name;
    435       1.1    dyoung 	in_score_src_t score_src;
    436       1.1    dyoung 	in_score_src_t scorers[IN_SCORE_SRC_MAX];
    437       1.1    dyoung 
    438       1.1    dyoung 	memset(&scorers, 0, sizeof(scorers));
    439       1.1    dyoung 	for (i = 0;
    440       1.1    dyoung 	     (name = strsep(&next, ",")) != NULL && i < IN_SCORE_SRC_MAX;
    441       1.1    dyoung 	     i++) {
    442       1.1    dyoung 		if (strcmp(name, "") == 0)
    443       1.1    dyoung 			break;
    444       1.1    dyoung 		if ((score_src = name_to_score_src(name)) == NULL)
    445       1.1    dyoung 			return EINVAL;
    446       1.1    dyoung 		scorers[i] = score_src;
    447       1.1    dyoung 	}
    448       1.1    dyoung 	if (i == IN_SCORE_SRC_MAX && name != NULL)
    449       1.1    dyoung 		return EFBIG;
    450       1.1    dyoung 	s = splnet();
    451       1.1    dyoung 	(void)memcpy(iss->iss_score_src, scorers, sizeof(iss->iss_score_src));
    452       1.1    dyoung         /* If iss affects a specific interface that used to use
    453       1.1    dyoung          * the default policy, increase the sequence number on the
    454       1.1    dyoung          * default policy, forcing routes that cache a source
    455       1.1    dyoung          * (rt_ifa) found by the default policy to refresh their
    456       1.1    dyoung          * cache.
    457       1.1    dyoung 	 */
    458       1.1    dyoung 	if (iss != &default_iss && iss->iss_score_src[0] == NULL &&
    459       1.1    dyoung 	    scorers[0] != NULL)
    460       1.1    dyoung 		default_iss.iss_seqno++;
    461       1.1    dyoung 	iss->iss_seqno++;
    462       1.1    dyoung 	splx(s);
    463       1.1    dyoung 	return 0;
    464       1.1    dyoung }
    465       1.1    dyoung 
    466       1.1    dyoung /*
    467       1.1    dyoung  * sysctl helper routine for net.inet.ip.interfaces.<interface>.selectsrc.
    468       1.1    dyoung  * Pulls the old value out as a human-readable string, interprets
    469       1.1    dyoung  * and records the new value.
    470       1.1    dyoung  */
    471       1.1    dyoung static int
    472       1.1    dyoung in_sysctl_selectsrc(SYSCTLFN_ARGS)
    473       1.1    dyoung {
    474       1.1    dyoung 	char policy[IN_SELECTSRC_LEN];
    475       1.1    dyoung 	int error;
    476       1.1    dyoung 	struct sysctlnode node;
    477       1.1    dyoung 	struct in_ifselsrc *iss;
    478       1.1    dyoung 
    479       1.1    dyoung 	node = *rnode;
    480       1.1    dyoung 	iss = (struct in_ifselsrc *)node.sysctl_data;
    481       1.1    dyoung 	if (oldp != NULL &&
    482       1.1    dyoung 	    (error = in_get_selectsrc(iss, policy, sizeof(policy))) >= sizeof(policy))
    483       1.1    dyoung 		return error;
    484       1.1    dyoung 	node.sysctl_data = &policy[0];
    485       1.1    dyoung 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
    486       1.1    dyoung 	if (error || newp == NULL)
    487       1.1    dyoung 		return (error);
    488       1.1    dyoung 
    489       1.1    dyoung 	return in_set_selectsrc(iss, policy);
    490       1.1    dyoung }
    491       1.1    dyoung 
    492       1.1    dyoung static const struct sysctlnode *
    493       1.1    dyoung in_domifattach_sysctl(struct in_ifsysctl *isc)
    494       1.1    dyoung {
    495       1.1    dyoung 	int rc;
    496       1.1    dyoung 	const struct sysctlnode *rnode;
    497       1.1    dyoung 
    498       1.1    dyoung 	if ((rc = sysctl_createv(&isc->isc_log, 0, NULL, &rnode,
    499       1.7    dyoung 	                         CTLFLAG_READONLY, CTLTYPE_NODE,
    500       1.1    dyoung 				 "interfaces", NULL,
    501       1.1    dyoung 				 NULL, 0, NULL, 0,
    502       1.1    dyoung 				 CTL_NET, PF_INET, IPPROTO_IP, CTL_CREATE,
    503       1.1    dyoung 				 CTL_EOL)) != 0) {
    504       1.1    dyoung 		printf("%s: could not create net.inet.ip.interfaces, rc = %d\n",
    505       1.1    dyoung 		    __func__, rc);
    506       1.1    dyoung 		return NULL;
    507       1.1    dyoung 	}
    508       1.1    dyoung 	if ((rc = sysctl_createv(&isc->isc_log, 0, &rnode, &rnode,
    509       1.7    dyoung 	                         CTLFLAG_READONLY, CTLTYPE_NODE,
    510       1.1    dyoung 				 isc->isc_ifp->if_xname,
    511       1.1    dyoung 				 SYSCTL_DESCR("interface ip options"),
    512       1.1    dyoung 				 NULL, 0, NULL, 0, CTL_CREATE, CTL_EOL)) != 0) {
    513       1.1    dyoung 		printf("%s: could not create net.inet.ip.interfaces.%s, "
    514       1.1    dyoung 		       "rc = %d\n", __func__, isc->isc_ifp->if_xname, rc);
    515       1.1    dyoung 		goto err;
    516       1.1    dyoung 	}
    517       1.1    dyoung 	if ((rc = sysctl_createv(&isc->isc_log, 0, &rnode, &rnode,
    518       1.1    dyoung 	                         CTLFLAG_READWRITE, CTLTYPE_STRING,
    519       1.1    dyoung 				 "selectsrc",
    520       1.1    dyoung 				 SYSCTL_DESCR("source selection policy"),
    521       1.1    dyoung 				 in_sysctl_selectsrc, 0,
    522  1.8.12.1      yamt 				 (void *)isc->isc_selsrc, IN_SELECTSRC_LEN,
    523       1.1    dyoung 				 CTL_CREATE, CTL_EOL)) != 0) {
    524       1.1    dyoung 		printf(
    525       1.1    dyoung 		    "%s: could not create net.inet.ip.%s.selectsrc, rc = %d\n",
    526       1.1    dyoung 		    __func__, isc->isc_ifp->if_xname, rc);
    527       1.1    dyoung 		goto err;
    528       1.1    dyoung 	}
    529       1.1    dyoung 	return rnode;
    530       1.1    dyoung err:
    531       1.1    dyoung 	sysctl_teardown(&isc->isc_log);
    532       1.1    dyoung 	return NULL;
    533       1.1    dyoung }
    534       1.1    dyoung 
    535       1.1    dyoung void *
    536       1.1    dyoung in_domifattach(struct ifnet *ifp)
    537       1.1    dyoung {
    538       1.1    dyoung 	struct in_ifsysctl *isc;
    539       1.1    dyoung 	struct in_ifselsrc *iss;
    540       1.1    dyoung 
    541       1.1    dyoung 	isc = (struct in_ifsysctl *)malloc(sizeof(*isc), M_IFADDR,
    542       1.1    dyoung 	    M_WAITOK | M_ZERO);
    543       1.1    dyoung 
    544       1.1    dyoung 	iss = (struct in_ifselsrc *)malloc(sizeof(*iss), M_IFADDR,
    545       1.1    dyoung 	    M_WAITOK | M_ZERO);
    546       1.1    dyoung 
    547       1.1    dyoung 	memcpy(&iss->iss_score_src[0], &initial_iss.iss_score_src[0],
    548       1.1    dyoung 	    MIN(sizeof(iss->iss_score_src), sizeof(initial_iss.iss_score_src)));
    549       1.1    dyoung 
    550       1.1    dyoung 	isc->isc_ifp = ifp;
    551       1.1    dyoung 	isc->isc_selsrc = iss;
    552       1.1    dyoung 
    553       1.1    dyoung 	if (in_domifattach_sysctl(isc) == NULL)
    554       1.1    dyoung 		goto err;
    555       1.1    dyoung 
    556       1.1    dyoung 	return isc;
    557       1.1    dyoung err:
    558       1.1    dyoung 	free(iss, M_IFADDR);
    559       1.1    dyoung 	free(isc, M_IFADDR);
    560       1.1    dyoung 	return NULL;
    561       1.1    dyoung }
    562       1.1    dyoung 
    563       1.1    dyoung void
    564       1.3  christos in_domifdetach(struct ifnet *ifp, void *aux)
    565       1.1    dyoung {
    566       1.1    dyoung 	struct in_ifsysctl *isc;
    567       1.2    dyoung 	struct in_ifselsrc *iss;
    568       1.1    dyoung 
    569       1.1    dyoung 	if (aux == NULL)
    570       1.1    dyoung 		return;
    571       1.1    dyoung 	isc = (struct in_ifsysctl *)aux;
    572       1.2    dyoung 	iss = isc->isc_selsrc;
    573       1.1    dyoung 	sysctl_teardown(&isc->isc_log);
    574       1.1    dyoung 	free(isc, M_IFADDR);
    575       1.2    dyoung 	free(iss, M_IFADDR);
    576       1.1    dyoung }
    577       1.1    dyoung #endif /* INET */
    578