1 /* $NetBSD: ether.c,v 1.11 1997/07/07 15:52:50 drochner Exp $ */ 2 3 /* 4 * Copyright (c) 1992 Regents of the University of California. 5 * All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp (LBL) 36 */ 37 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include <sys/param.h> 42 #include <sys/socket.h> 43 #include <string.h> 44 45 #include <net/if.h> 46 #include <netinet/in.h> 47 #include <netinet/if_ether.h> 48 #include <netinet/in_systm.h> 49 #include <netinet/ip.h> 50 51 #include "stand.h" 52 #include "net.h" 53 #include "netif.h" 54 55 /* Caller must leave room for ethernet header in front!! */ 56 ssize_t 57 sendether(struct iodesc *d, void *pkt, size_t len, uint8_t *dea, int etype) 58 { 59 ssize_t n; 60 struct ether_header *eh; 61 62 #ifdef ETHER_DEBUG 63 if (debug) 64 printf("sendether: called\n"); 65 #endif 66 67 eh = (struct ether_header *)pkt - 1; 68 len += sizeof(*eh); 69 70 MACPY(d->myea, eh->ether_shost); /* by byte */ 71 MACPY(dea, eh->ether_dhost); /* by byte */ 72 eh->ether_type = htons(etype); 73 74 n = netif_put(d, eh, len); 75 if (n == -1 || n < sizeof(*eh)) 76 return (-1); 77 78 n -= sizeof(*eh); 79 return (n); 80 } 81 82 /* 83 * Get a packet of any Ethernet type, with our address or 84 * the broadcast address. Save the Ether type in etype. 85 * Unless there is an error, we pass the whole packet and the unencapsulated 86 * data. 87 */ 88 ssize_t 89 readether(struct iodesc *d, void **pkt, void **payload, time_t tleft, 90 uint16_t *etype) 91 { 92 ssize_t n; 93 struct ether_header *eh; 94 void *ptr; 95 96 #ifdef ETHER_DEBUG 97 if (debug) 98 printf("readether: called\n"); 99 #endif 100 101 ptr = NULL; 102 n = netif_get(d, &ptr, tleft); 103 if (n == -1 || n < sizeof(*eh)) { 104 free(ptr); 105 return (-1); 106 } 107 108 eh = (struct ether_header *)((uintptr_t)ptr + ETHER_ALIGN); 109 /* Validate Ethernet address. */ 110 if (bcmp(d->myea, eh->ether_dhost, 6) != 0 && 111 bcmp(bcea, eh->ether_dhost, 6) != 0) { 112 #ifdef ETHER_DEBUG 113 if (debug) 114 printf("readether: not ours (ea=%s)\n", 115 ether_sprintf(eh->ether_dhost)); 116 #endif 117 free(ptr); 118 return (-1); 119 } 120 121 *pkt = ptr; 122 *payload = (void *)((uintptr_t)eh + sizeof(*eh)); 123 *etype = ntohs(eh->ether_type); 124 125 n -= sizeof(*eh); 126 return (n); 127 } 128 129 /* 130 * Convert Ethernet address to printable (loggable) representation. 131 */ 132 static char digits[] = "0123456789abcdef"; 133 char * 134 ether_sprintf(u_char *ap) 135 { 136 int i; 137 static char etherbuf[18]; 138 char *cp = etherbuf; 139 140 for (i = 0; i < 6; i++) { 141 *cp++ = digits[*ap >> 4]; 142 *cp++ = digits[*ap++ & 0xf]; 143 *cp++ = ':'; 144 } 145 *--cp = 0; 146 return (etherbuf); 147 } 148