link_proto.c revision 1.2
1 /* $NetBSD: link_proto.c,v 1.2 2007/08/07 04:06:20 dyoung Exp $ */ 2 3 /*- 4 * Copyright (c) 1982, 1986, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)uipc_proto.c 8.2 (Berkeley) 2/14/95 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: link_proto.c,v 1.2 2007/08/07 04:06:20 dyoung Exp $"); 36 37 #include <sys/param.h> 38 #include <sys/socket.h> 39 #include <sys/protosw.h> 40 #include <sys/domain.h> 41 #include <sys/mbuf.h> 42 #include <sys/un.h> 43 #include <sys/socketvar.h> 44 45 #include <net/if.h> 46 #include <net/if_dl.h> 47 #include <net/raw_cb.h> 48 49 static int sockaddr_dl_cmp(const struct sockaddr *, const struct sockaddr *); 50 51 /* 52 * Definitions of protocols supported in the link-layer domain. 53 */ 54 55 DOMAIN_DEFINE(linkdomain); /* forward define and add to link set */ 56 57 POOL_INIT(sockaddr_dl_pool, sizeof(struct sockaddr_dl), 0, 0, 0, 58 "sockaddr_dl_pool", NULL, IPL_NET); 59 60 struct domain linkdomain = { 61 .dom_family = AF_LINK, 62 .dom_name = "link", 63 .dom_externalize = NULL, 64 .dom_dispose = NULL, 65 .dom_protosw = NULL, 66 .dom_protoswNPROTOSW = NULL, 67 .dom_sa_pool = &sockaddr_dl_pool, 68 .dom_sa_len = sizeof(struct sockaddr_dl), 69 .dom_sockaddr_cmp = sockaddr_dl_cmp 70 }; 71 72 /* Compare the field at byte offsets [fieldstart, fieldend) in 73 * two memory regions, [l, l + llen) and [r, r + llen). 74 */ 75 static inline int 76 submemcmp(const void *l, const void *r, 77 const uint_fast8_t llen, const uint_fast8_t rlen, 78 const uint_fast8_t fieldstart, const uint_fast8_t fieldend) 79 { 80 uint_fast8_t cmpend, minlen; 81 const uint8_t *lb = l, *rb = r; 82 int rc; 83 84 minlen = MIN(llen, rlen); 85 86 /* The field is missing from one region. The shorter region is the 87 * lesser region. 88 */ 89 if (fieldstart >= minlen) 90 return llen - rlen; 91 92 /* Two empty, present fields are always equal. */ 93 if (fieldstart > fieldend) 94 return 0; 95 96 cmpend = MIN(fieldend, minlen); 97 98 rc = memcmp(&lb[fieldstart], &rb[fieldstart], cmpend - fieldstart); 99 100 if (rc != 0) 101 return rc; 102 /* If one or both fields are truncated, then the shorter is the lesser 103 * field. 104 */ 105 if (minlen < fieldend) 106 return llen - rlen; 107 /* Fields are full-length and equal. The fields are equal. */ 108 return 0; 109 } 110 111 uint8_t 112 sockaddr_dl_measure(uint8_t namelen, uint8_t addrlen) 113 { 114 return offsetof(struct sockaddr_dl, sdl_data[namelen + addrlen]); 115 } 116 117 void 118 sockaddr_dl_init(struct sockaddr_dl *sdl, uint16_t ifindex, uint8_t type, 119 const void *name, uint8_t namelen, const void *addr, uint8_t addrlen) 120 { 121 sdl->sdl_family = AF_LINK; 122 sdl->sdl_slen = 0; 123 sdl->sdl_len = sockaddr_dl_measure(namelen, addrlen); 124 KASSERT(sdl->sdl_len <= sizeof(*sdl)); 125 sdl->sdl_index = ifindex; 126 sdl->sdl_type = type; 127 memset(&sdl->sdl_data[0], 0, sizeof(sdl->sdl_data)); 128 if (name != NULL) 129 memcpy(&sdl->sdl_data[0], name, namelen); 130 sdl->sdl_nlen = namelen; 131 if (addr != NULL) 132 memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen); 133 sdl->sdl_alen = addrlen; 134 } 135 136 static int 137 sockaddr_dl_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2) 138 { 139 int rc; 140 const uint_fast8_t indexofs = offsetof(struct sockaddr_dl, sdl_index); 141 const uint_fast8_t nlenofs = offsetof(struct sockaddr_dl, sdl_nlen); 142 uint_fast8_t dataofs = offsetof(struct sockaddr_dl, sdl_data[0]); 143 const struct sockaddr_dl *sdl1, *sdl2; 144 145 sdl1 = satocsdl(sa1); 146 sdl2 = satocsdl(sa2); 147 148 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 149 indexofs, nlenofs); 150 151 if (rc != 0) 152 return rc; 153 154 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 155 dataofs, dataofs + MIN(sdl1->sdl_nlen, sdl2->sdl_nlen)); 156 157 if (rc != 0) 158 return rc; 159 160 if (sdl1->sdl_nlen != sdl2->sdl_nlen) 161 return sdl1->sdl_nlen - sdl2->sdl_nlen; 162 163 dataofs += sdl1->sdl_nlen; 164 165 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 166 dataofs, dataofs + MIN(sdl1->sdl_alen, sdl2->sdl_alen)); 167 168 if (rc != 0) 169 return rc; 170 171 if (sdl1->sdl_alen != sdl2->sdl_alen) 172 return sdl1->sdl_alen - sdl2->sdl_alen; 173 174 dataofs += sdl1->sdl_alen; 175 176 rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len, 177 dataofs, dataofs + MIN(sdl1->sdl_slen, sdl2->sdl_slen)); 178 179 if (sdl1->sdl_slen != sdl2->sdl_slen) 180 return sdl1->sdl_slen - sdl2->sdl_slen; 181 182 return sdl1->sdl_len - sdl2->sdl_len; 183 } 184 185 struct sockaddr_dl * 186 sockaddr_dl_setaddr(struct sockaddr_dl *sdl, const void *addr, uint8_t addrlen) 187 { 188 uint_fast8_t endofs; 189 190 endofs = 191 offsetof(struct sockaddr_dl, sdl_data[sdl->sdl_nlen + addrlen]); 192 193 if (endofs > sizeof(struct sockaddr_dl)) { 194 printf("%s: too long: %" PRIu8 " bytes\n", __func__, addrlen); 195 sdl->sdl_alen = 0; 196 return NULL; 197 } 198 memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen); 199 sdl->sdl_alen = addrlen; 200 return sdl; 201 } 202
Indexes created Sat Sep 27 14:09:57 GMT 2025