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 #include <sys/param.h> 40 #include <sys/socket.h> 41 #include <string.h> 42 43 #include <net/if.h> 44 #include <netinet/in.h> 45 #include <netinet/if_ether.h> 46 #include <netinet/in_systm.h> 47 #include <netinet/ip.h> 48 49 #include "stand.h" 50 #include "net.h" 51 #include "netif.h" 52 53 /* Caller must leave room for ethernet header in front!! */ 54 ssize_t 55 sendether(struct iodesc *d, void *pkt, size_t len, uint8_t *dea, int etype) 56 { 57 ssize_t n; 58 struct ether_header *eh; 59 60 #ifdef ETHER_DEBUG 61 if (debug) 62 printf("sendether: called\n"); 63 #endif 64 65 eh = (struct ether_header *)pkt - 1; 66 len += sizeof(*eh); 67 68 MACPY(d->myea, eh->ether_shost); /* by byte */ 69 MACPY(dea, eh->ether_dhost); /* by byte */ 70 eh->ether_type = htons(etype); 71 72 n = netif_put(d, eh, len); 73 if (n == -1 || n < sizeof(*eh)) 74 return (-1); 75 76 n -= sizeof(*eh); 77 return (n); 78 } 79 80 /* 81 * Get a packet of any Ethernet type, with our address or 82 * the broadcast address. Save the Ether type in etype. 83 * Unless there is an error, we pass the whole packet and the unencapsulated 84 * data. 85 */ 86 ssize_t 87 readether(struct iodesc *d, void **pkt, void **payload, time_t tleft, 88 uint16_t *etype) 89 { 90 ssize_t n; 91 struct ether_header *eh; 92 void *ptr; 93 94 #ifdef ETHER_DEBUG 95 if (debug) 96 printf("readether: called\n"); 97 #endif 98 99 ptr = NULL; 100 n = netif_get(d, &ptr, tleft); 101 if (n == -1 || n < sizeof(*eh)) { 102 free(ptr); 103 return (-1); 104 } 105 106 eh = (struct ether_header *)((uintptr_t)ptr + ETHER_ALIGN); 107 /* Validate Ethernet address. */ 108 if (bcmp(d->myea, eh->ether_dhost, 6) != 0 && 109 bcmp(bcea, eh->ether_dhost, 6) != 0) { 110 #ifdef ETHER_DEBUG 111 if (debug) 112 printf("readether: not ours (ea=%s)\n", 113 ether_sprintf(eh->ether_dhost)); 114 #endif 115 free(ptr); 116 return (-1); 117 } 118 119 *pkt = ptr; 120 *payload = (void *)((uintptr_t)eh + sizeof(*eh)); 121 *etype = ntohs(eh->ether_type); 122 123 n -= sizeof(*eh); 124 return (n); 125 } 126 127 /* 128 * Convert Ethernet address to printable (loggable) representation. 129 */ 130 static char digits[] = "0123456789abcdef"; 131 char * 132 ether_sprintf(u_char *ap) 133 { 134 int i; 135 static char etherbuf[18]; 136 char *cp = etherbuf; 137 138 for (i = 0; i < 6; i++) { 139 *cp++ = digits[*ap >> 4]; 140 *cp++ = digits[*ap++ & 0xf]; 141 *cp++ = ':'; 142 } 143 *--cp = 0; 144 return (etherbuf); 145 } 146