ethers.c revision 1.15
1 /* $NetBSD: ethers.c,v 1.15 1999/09/16 11:45:11 lukem Exp $ */ 2 3 /* 4 * ethers(3N) a la Sun. 5 * 6 * Written by Roland McGrath <roland (at) frob.com> 10/14/93. 7 * Public domain. 8 */ 9 10 #include "namespace.h" 11 #include <sys/param.h> 12 #include <sys/socket.h> 13 14 #include <net/if.h> 15 #include <net/if_ether.h> 16 #include <netinet/in.h> 17 18 #include <assert.h> 19 #include <errno.h> 20 #include <paths.h> 21 #include <stdio.h> 22 #include <stdlib.h> 23 #include <string.h> 24 25 #ifdef YP 26 #include <rpcsvc/ypclnt.h> 27 #endif 28 29 #ifdef __weak_alias 30 __weak_alias(ether_aton,_ether_aton); 31 __weak_alias(ether_hostton,_ether_hostton); 32 __weak_alias(ether_line,_ether_line); 33 __weak_alias(ether_ntoa,_ether_ntoa); 34 __weak_alias(ether_ntohost,_ether_ntohost); 35 #endif 36 37 #ifndef _PATH_ETHERS 38 #define _PATH_ETHERS "/etc/ethers" 39 #endif 40 41 char * 42 ether_ntoa(e) 43 struct ether_addr *e; 44 { 45 static char a[18]; 46 47 _DIAGASSERT(e != NULL); 48 #ifdef _DIAGNOSTIC 49 if (e == NULL) 50 return NULL; 51 #endif 52 53 snprintf(a, sizeof a, "%02x:%02x:%02x:%02x:%02x:%02x", 54 e->ether_addr_octet[0], e->ether_addr_octet[1], 55 e->ether_addr_octet[2], e->ether_addr_octet[3], 56 e->ether_addr_octet[4], e->ether_addr_octet[5]); 57 return a; 58 } 59 60 struct ether_addr * 61 ether_aton(s) 62 const char *s; 63 { 64 static struct ether_addr n; 65 u_int i[6]; 66 67 _DIAGASSERT(s != NULL); 68 #ifdef _DIAGNOSTIC 69 if (s == NULL) 70 return NULL; 71 #endif 72 73 if (sscanf(s, " %x:%x:%x:%x:%x:%x ", &i[0], &i[1], 74 &i[2], &i[3], &i[4], &i[5]) == 6) { 75 n.ether_addr_octet[0] = (u_char)i[0]; 76 n.ether_addr_octet[1] = (u_char)i[1]; 77 n.ether_addr_octet[2] = (u_char)i[2]; 78 n.ether_addr_octet[3] = (u_char)i[3]; 79 n.ether_addr_octet[4] = (u_char)i[4]; 80 n.ether_addr_octet[5] = (u_char)i[5]; 81 return &n; 82 } 83 return NULL; 84 } 85 86 int 87 ether_ntohost(hostname, e) 88 char *hostname; 89 struct ether_addr *e; 90 { 91 FILE *f; 92 char *p; 93 size_t len; 94 struct ether_addr try; 95 #ifdef YP 96 char trybuf[sizeof "xx:xx:xx:xx:xx:xx"]; 97 int trylen; 98 #endif 99 100 _DIAGASSERT(hostname != NULL); 101 _DIAGASSERT(e != NULL); 102 #ifdef _DIAGNOSTIC 103 if (hostname == NULL || e == NULL) { 104 errno = EFAULT; 105 return -1; 106 } 107 #endif 108 109 #ifdef YP 110 trylen = snprintf(trybuf, sizeof trybuf, "%x:%x:%x:%x:%x:%x", 111 e->ether_addr_octet[0], e->ether_addr_octet[1], 112 e->ether_addr_octet[2], e->ether_addr_octet[3], 113 e->ether_addr_octet[4], e->ether_addr_octet[5]); 114 #endif 115 116 f = fopen(_PATH_ETHERS, "r"); 117 if (f == NULL) 118 return -1; 119 while ((p = fgetln(f, &len)) != NULL) { 120 if (p[len - 1] != '\n') 121 continue; /* skip lines w/o \n */ 122 p[--len] = '\0'; 123 #ifdef YP 124 /* A + in the file means try YP now. */ 125 if (len == 1 && *p == '+') { 126 char *ypbuf, *ypdom; 127 int ypbuflen; 128 129 if (yp_get_default_domain(&ypdom)) 130 continue; 131 if (yp_match(ypdom, "ethers.byaddr", trybuf, 132 trylen, &ypbuf, &ypbuflen)) 133 continue; 134 if (ether_line(ypbuf, &try, hostname) == 0) { 135 free(ypbuf); 136 (void)fclose(f); 137 return 0; 138 } 139 free(ypbuf); 140 continue; 141 } 142 #endif 143 if (ether_line(p, &try, hostname) == 0 && 144 memcmp(&try, e, sizeof try) == 0) { 145 (void)fclose(f); 146 return 0; 147 } 148 } 149 (void)fclose(f); 150 errno = ENOENT; 151 return -1; 152 } 153 154 int 155 ether_hostton(hostname, e) 156 const char *hostname; 157 struct ether_addr *e; 158 { 159 FILE *f; 160 char *p; 161 size_t len; 162 char try[MAXHOSTNAMELEN + 1]; 163 #ifdef YP 164 int hostlen = strlen(hostname); 165 #endif 166 167 _DIAGASSERT(hostname != NULL); 168 _DIAGASSERT(e != NULL); 169 #ifdef _DIAGNOSTIC 170 if (hostname == NULL || e == NULL) { 171 errno = EFAULT; 172 return -1; 173 } 174 #endif 175 176 f = fopen(_PATH_ETHERS, "r"); 177 if (f==NULL) 178 return -1; 179 180 while ((p = fgetln(f, &len)) != NULL) { 181 if (p[len - 1] != '\n') 182 continue; /* skip lines w/o \n */ 183 p[--len] = '\0'; 184 #ifdef YP 185 /* A + in the file means try YP now. */ 186 if (len == 1 && *p == '+') { 187 char *ypbuf, *ypdom; 188 int ypbuflen; 189 190 if (yp_get_default_domain(&ypdom)) 191 continue; 192 if (yp_match(ypdom, "ethers.byname", hostname, hostlen, 193 &ypbuf, &ypbuflen)) 194 continue; 195 if (ether_line(ypbuf, e, try) == 0) { 196 free(ypbuf); 197 (void)fclose(f); 198 return 0; 199 } 200 free(ypbuf); 201 continue; 202 } 203 #endif 204 if (ether_line(p, e, try) == 0 && strcmp(hostname, try) == 0) { 205 (void)fclose(f); 206 return 0; 207 } 208 } 209 (void)fclose(f); 210 errno = ENOENT; 211 return -1; 212 } 213 214 int 215 ether_line(l, e, hostname) 216 const char *l; 217 struct ether_addr *e; 218 char *hostname; 219 { 220 u_int i[6]; 221 static char buf[sizeof " %x:%x:%x:%x:%x:%x %s\\n" + 21]; 222 /* XXX: 21 == strlen (ASCII representation of 2^64) */ 223 224 _DIAGASSERT(l != NULL); 225 _DIAGASSERT(e != NULL); 226 _DIAGASSERT(hostname != NULL); 227 #ifdef _DIAGNOSTIC 228 if (l == NULL || e == NULL || hostname == NULL) { 229 errno = EFAULT; 230 return -1; 231 } 232 #endif 233 234 if (! buf[0]) 235 snprintf(buf, sizeof buf, " %%x:%%x:%%x:%%x:%%x:%%x %%%ds\\n", 236 MAXHOSTNAMELEN); 237 if (sscanf(l, buf, 238 &i[0], &i[1], &i[2], &i[3], &i[4], &i[5], hostname) == 7) { 239 e->ether_addr_octet[0] = (u_char)i[0]; 240 e->ether_addr_octet[1] = (u_char)i[1]; 241 e->ether_addr_octet[2] = (u_char)i[2]; 242 e->ether_addr_octet[3] = (u_char)i[3]; 243 e->ether_addr_octet[4] = (u_char)i[4]; 244 e->ether_addr_octet[5] = (u_char)i[5]; 245 return 0; 246 } 247 errno = EINVAL; 248 return -1; 249 } 250
Indexes created Mon Sep 22 05:09:51 GMT 2025