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 36 #include <sys/cdefs.h> 37 #include <sys/param.h> 38 #include <sys/socket.h> 39 #include <string.h> 40 41 #include <net/if.h> 42 #include <netinet/in.h> 43 #include <netinet/if_ether.h> 44 #include <netinet/in_systm.h> 45 #include <netinet/ip.h> 46 47 #include "stand.h" 48 #include "net.h" 49 #include "netif.h" 50 51 /* Caller must leave room for ethernet header in front!! */ 52 ssize_t 53 sendether(struct iodesc *d, void *pkt, size_t len, uint8_t *dea, int etype) 54 { 55 ssize_t n; 56 struct ether_header *eh; 57 58 #ifdef ETHER_DEBUG 59 if (debug) 60 printf("sendether: called\n"); 61 #endif 62 63 eh = (struct ether_header *)pkt - 1; 64 len += sizeof(*eh); 65 66 MACPY(d->myea, eh->ether_shost); /* by byte */ 67 MACPY(dea, eh->ether_dhost); /* by byte */ 68 eh->ether_type = htons(etype); 69 70 n = netif_put(d, eh, len); 71 if (n == -1 || n < sizeof(*eh)) 72 return (-1); 73 74 n -= sizeof(*eh); 75 return (n); 76 } 77 78 /* 79 * Get a packet of any Ethernet type, with our address or 80 * the broadcast address. Save the Ether type in etype. 81 * Unless there is an error, we pass the whole packet and the unencapsulated 82 * data. 83 */ 84 ssize_t 85 readether(struct iodesc *d, void **pkt, void **payload, time_t tleft, 86 uint16_t *etype) 87 { 88 ssize_t n; 89 struct ether_header *eh; 90 void *ptr; 91 92 #ifdef ETHER_DEBUG 93 if (debug) 94 printf("readether: called\n"); 95 #endif 96 97 ptr = NULL; 98 n = netif_get(d, &ptr, tleft); 99 if (n == -1 || n < sizeof(*eh)) { 100 free(ptr); 101 return (-1); 102 } 103 104 eh = (struct ether_header *)((uintptr_t)ptr + ETHER_ALIGN); 105 /* Validate Ethernet address. */ 106 if (bcmp(d->myea, eh->ether_dhost, 6) != 0 && 107 bcmp(bcea, eh->ether_dhost, 6) != 0) { 108 #ifdef ETHER_DEBUG 109 if (debug) 110 printf("readether: not ours (ea=%s)\n", 111 ether_sprintf(eh->ether_dhost)); 112 #endif 113 free(ptr); 114 return (-1); 115 } 116 117 *pkt = ptr; 118 *payload = (void *)((uintptr_t)eh + sizeof(*eh)); 119 *etype = ntohs(eh->ether_type); 120 121 n -= sizeof(*eh); 122 return (n); 123 } 124 125 /* 126 * Convert Ethernet address to printable (loggable) representation. 127 */ 128 static char digits[] = "0123456789abcdef"; 129 char * 130 ether_sprintf(u_char *ap) 131 { 132 int i; 133 static char etherbuf[18]; 134 char *cp = etherbuf; 135 136 for (i = 0; i < 6; i++) { 137 *cp++ = digits[*ap >> 4]; 138 *cp++ = digits[*ap++ & 0xf]; 139 *cp++ = ':'; 140 } 141 *--cp = 0; 142 return (etherbuf); 143 } 144