1 /* $NetBSD: net.c,v 1.20 1997/12/26 22:41:30 scottr 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/param.h> 37 #include <sys/socket.h> 38 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 46 #include <netinet/ip.h> 47 #include <netinet/ip_var.h> 48 #include <netinet/udp.h> 49 #include <netinet/udp_var.h> 50 51 #include "stand.h" 52 #include "net.h" 53 54 /* 55 * Maximum wait time for sending and receiving before we give up and timeout. 56 * If set to 0, operations will eventually timeout completely, but send/recv 57 * timeouts must progress exponentially from MINTMO to MAXTMO before final 58 * timeout is hit. 59 */ 60 #ifndef MAXWAIT 61 #define MAXWAIT 300 /* seconds */ 62 #endif 63 64 #if MAXWAIT < 0 65 #error MAXWAIT must not be a negative number 66 #endif 67 68 /* 69 * Send a packet and wait for a reply, with exponential backoff. 70 * 71 * The send routine must return the actual number of bytes written, 72 * or -1 on error. 73 * 74 * The receive routine can indicate success by returning the number of 75 * bytes read; it can return 0 to indicate EOF; it can return -1 with a 76 * non-zero errno to indicate failure; finally, it can return -1 with a 77 * zero errno to indicate it isn't done yet. 78 */ 79 ssize_t 80 sendrecv(struct iodesc *d, 81 ssize_t (*sproc)(struct iodesc *, void *, size_t), 82 void *sbuf, size_t ssize, 83 ssize_t (*rproc)(struct iodesc *, void **, void **, time_t, void *), 84 void **pkt, void **payload, void *recv_extra) 85 { 86 ssize_t cc; 87 time_t t, tmo, tlast; 88 time_t tref; 89 long tleft; 90 91 #ifdef NET_DEBUG 92 if (debug) 93 printf("sendrecv: called\n"); 94 #endif 95 96 tmo = MINTMO; 97 tlast = 0; 98 tleft = 0; 99 tref = t = getsecs(); 100 for (;;) { 101 if (MAXWAIT > 0 && (t - tref) >= MAXWAIT) { 102 errno = ETIMEDOUT; 103 return -1; 104 } 105 if (tleft <= 0) { 106 if (tmo >= MAXTMO) { 107 errno = ETIMEDOUT; 108 return -1; 109 } 110 cc = (*sproc)(d, sbuf, ssize); 111 if (cc != -1 && cc < ssize) 112 panic("sendrecv: short write! (%zd < %zd)", 113 cc, ssize); 114 115 tleft = tmo; 116 tmo += MINTMO; 117 if (tmo > MAXTMO) 118 tmo = MAXTMO; 119 120 if (cc == -1) { 121 /* Error on transmit; wait before retrying */ 122 while ((getsecs() - t) < tmo) 123 ; 124 tleft = 0; 125 continue; 126 } 127 128 tlast = t; 129 } 130 131 /* Try to get a packet and process it. */ 132 cc = (*rproc)(d, pkt, payload, tleft, recv_extra); 133 /* Return on data, EOF or real error. */ 134 if (cc != -1 || (errno != 0 && errno != ETIMEDOUT)) 135 return (cc); 136 137 /* Timed out or didn't get the packet we're waiting for */ 138 t = getsecs(); 139 tleft -= t - tlast; 140 tlast = t; 141 } 142 } 143 144 /* 145 * Like inet_addr() in the C library, but we only accept base-10. 146 * Return values are in network order. 147 */ 148 n_long 149 inet_addr(char *cp) 150 { 151 u_long val; 152 int n; 153 char c; 154 u_int parts[4]; 155 u_int *pp = parts; 156 157 for (;;) { 158 /* 159 * Collect number up to ``.''. 160 * Values are specified as for C: 161 * 0x=hex, 0=octal, other=decimal. 162 */ 163 val = 0; 164 while ((c = *cp) != '\0') { 165 if (c >= '0' && c <= '9') { 166 val = (val * 10) + (c - '0'); 167 cp++; 168 continue; 169 } 170 break; 171 } 172 if (*cp == '.') { 173 /* 174 * Internet format: 175 * a.b.c.d 176 * a.b.c (with c treated as 16-bits) 177 * a.b (with b treated as 24 bits) 178 */ 179 if (pp >= parts + 3 || val > 0xff) 180 goto bad; 181 *pp++ = val, cp++; 182 } else 183 break; 184 } 185 /* 186 * Check for trailing characters. 187 */ 188 if (*cp != '\0') 189 goto bad; 190 191 /* 192 * Concoct the address according to 193 * the number of parts specified. 194 */ 195 n = pp - parts + 1; 196 switch (n) { 197 198 case 1: /* a -- 32 bits */ 199 break; 200 201 case 2: /* a.b -- 8.24 bits */ 202 if (val > 0xffffff) 203 goto bad; 204 val |= parts[0] << 24; 205 break; 206 207 case 3: /* a.b.c -- 8.8.16 bits */ 208 if (val > 0xffff) 209 goto bad; 210 val |= (parts[0] << 24) | (parts[1] << 16); 211 break; 212 213 case 4: /* a.b.c.d -- 8.8.8.8 bits */ 214 if (val > 0xff) 215 goto bad; 216 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); 217 break; 218 } 219 220 return (htonl(val)); 221 bad: 222 return (htonl(INADDR_NONE)); 223 } 224 225 char * 226 inet_ntoa(struct in_addr ia) 227 { 228 return (intoa(ia.s_addr)); 229 } 230 231 /* Similar to inet_ntoa() */ 232 char * 233 intoa(n_long addr) 234 { 235 char *cp; 236 u_int byte; 237 int n; 238 static char buf[17]; /* strlen(".255.255.255.255") + 1 */ 239 240 addr = ntohl(addr); 241 cp = &buf[sizeof buf]; 242 *--cp = '\0'; 243 244 n = 4; 245 do { 246 byte = addr & 0xff; 247 *--cp = byte % 10 + '0'; 248 byte /= 10; 249 if (byte > 0) { 250 *--cp = byte % 10 + '0'; 251 byte /= 10; 252 if (byte > 0) 253 *--cp = byte + '0'; 254 } 255 *--cp = '.'; 256 addr >>= 8; 257 } while (--n > 0); 258 259 return (cp+1); 260 } 261 262 static char * 263 number(char *s, n_long *n) 264 { 265 for (*n = 0; isdigit(*s); s++) 266 *n = (*n * 10) + *s - '0'; 267 return s; 268 } 269 270 n_long 271 ip_convertaddr(char *p) 272 { 273 #define IP_ANYADDR 0 274 n_long addr = 0, n; 275 276 if (p == NULL || *p == '\0') 277 return IP_ANYADDR; 278 p = number(p, &n); 279 addr |= (n << 24) & 0xff000000; 280 if (*p == '\0' || *p++ != '.') 281 return IP_ANYADDR; 282 p = number(p, &n); 283 addr |= (n << 16) & 0xff0000; 284 if (*p == '\0' || *p++ != '.') 285 return IP_ANYADDR; 286 p = number(p, &n); 287 addr |= (n << 8) & 0xff00; 288 if (*p == '\0' || *p++ != '.') 289 return IP_ANYADDR; 290 p = number(p, &n); 291 addr |= n & 0xff; 292 if (*p != '\0') 293 return IP_ANYADDR; 294 295 return htonl(addr); 296 } 297