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 * @(#) 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 44 #include <string.h> 45 46 #include <net/if.h> 47 #include <netinet/in.h> 48 #include <netinet/if_ether.h> 49 #include <netinet/in_systm.h> 50 51 #include <netinet/ip.h> 52 #include <netinet/ip_var.h> 53 #include <netinet/udp.h> 54 #include <netinet/udp_var.h> 55 56 #include "stand.h" 57 #include "net.h" 58 59 /* 60 * Maximum wait time for sending and receiving before we give up and timeout. 61 * If set to 0, operations will eventually timeout completely, but send/recv 62 * timeouts must progress exponentially from MINTMO to MAXTMO before final 63 * timeout is hit. 64 */ 65 #ifndef MAXWAIT 66 #define MAXWAIT 300 /* seconds */ 67 #endif 68 69 #if MAXWAIT < 0 70 #error MAXWAIT must not be a negative number 71 #endif 72 73 /* 74 * Send a packet and wait for a reply, with exponential backoff. 75 * 76 * The send routine must return the actual number of bytes written, 77 * or -1 on error. 78 * 79 * The receive routine can indicate success by returning the number of 80 * bytes read; it can return 0 to indicate EOF; it can return -1 with a 81 * non-zero errno to indicate failure; finally, it can return -1 with a 82 * zero errno to indicate it isn't done yet. 83 */ 84 ssize_t 85 sendrecv(struct iodesc *d, 86 ssize_t (*sproc)(struct iodesc *, void *, size_t), 87 void *sbuf, size_t ssize, 88 ssize_t (*rproc)(struct iodesc *, void **, void **, time_t, void *), 89 void **pkt, void **payload, void *recv_extra) 90 { 91 ssize_t cc; 92 time_t t, tmo, tlast; 93 time_t tref; 94 long tleft; 95 96 #ifdef NET_DEBUG 97 if (debug) 98 printf("sendrecv: called\n"); 99 #endif 100 101 tmo = MINTMO; 102 tlast = 0; 103 tleft = 0; 104 tref = t = getsecs(); 105 for (;;) { 106 if (MAXWAIT > 0 && (t - tref) >= MAXWAIT) { 107 errno = ETIMEDOUT; 108 return -1; 109 } 110 if (tleft <= 0) { 111 if (tmo >= MAXTMO) { 112 errno = ETIMEDOUT; 113 return -1; 114 } 115 cc = (*sproc)(d, sbuf, ssize); 116 if (cc != -1 && cc < ssize) 117 panic("sendrecv: short write! (%zd < %zd)", 118 cc, ssize); 119 120 tleft = tmo; 121 tmo += MINTMO; 122 if (tmo > MAXTMO) 123 tmo = MAXTMO; 124 125 if (cc == -1) { 126 /* Error on transmit; wait before retrying */ 127 while ((getsecs() - t) < tmo) 128 ; 129 tleft = 0; 130 continue; 131 } 132 133 tlast = t; 134 } 135 136 /* Try to get a packet and process it. */ 137 cc = (*rproc)(d, pkt, payload, tleft, recv_extra); 138 /* Return on data, EOF or real error. */ 139 if (cc != -1 || (errno != 0 && errno != ETIMEDOUT)) 140 return (cc); 141 142 /* Timed out or didn't get the packet we're waiting for */ 143 t = getsecs(); 144 tleft -= t - tlast; 145 tlast = t; 146 } 147 } 148 149 /* 150 * Like inet_addr() in the C library, but we only accept base-10. 151 * Return values are in network order. 152 */ 153 n_long 154 inet_addr(char *cp) 155 { 156 u_long val; 157 int n; 158 char c; 159 u_int parts[4]; 160 u_int *pp = parts; 161 162 for (;;) { 163 /* 164 * Collect number up to ``.''. 165 * Values are specified as for C: 166 * 0x=hex, 0=octal, other=decimal. 167 */ 168 val = 0; 169 while ((c = *cp) != '\0') { 170 if (c >= '0' && c <= '9') { 171 val = (val * 10) + (c - '0'); 172 cp++; 173 continue; 174 } 175 break; 176 } 177 if (*cp == '.') { 178 /* 179 * Internet format: 180 * a.b.c.d 181 * a.b.c (with c treated as 16-bits) 182 * a.b (with b treated as 24 bits) 183 */ 184 if (pp >= parts + 3 || val > 0xff) 185 goto bad; 186 *pp++ = val, cp++; 187 } else 188 break; 189 } 190 /* 191 * Check for trailing characters. 192 */ 193 if (*cp != '\0') 194 goto bad; 195 196 /* 197 * Concoct the address according to 198 * the number of parts specified. 199 */ 200 n = pp - parts + 1; 201 switch (n) { 202 203 case 1: /* a -- 32 bits */ 204 break; 205 206 case 2: /* a.b -- 8.24 bits */ 207 if (val > 0xffffff) 208 goto bad; 209 val |= parts[0] << 24; 210 break; 211 212 case 3: /* a.b.c -- 8.8.16 bits */ 213 if (val > 0xffff) 214 goto bad; 215 val |= (parts[0] << 24) | (parts[1] << 16); 216 break; 217 218 case 4: /* a.b.c.d -- 8.8.8.8 bits */ 219 if (val > 0xff) 220 goto bad; 221 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); 222 break; 223 } 224 225 return (htonl(val)); 226 bad: 227 return (htonl(INADDR_NONE)); 228 } 229 230 char * 231 inet_ntoa(struct in_addr ia) 232 { 233 return (intoa(ia.s_addr)); 234 } 235 236 /* Similar to inet_ntoa() */ 237 char * 238 intoa(n_long addr) 239 { 240 char *cp; 241 u_int byte; 242 int n; 243 static char buf[17]; /* strlen(".255.255.255.255") + 1 */ 244 245 addr = ntohl(addr); 246 cp = &buf[sizeof buf]; 247 *--cp = '\0'; 248 249 n = 4; 250 do { 251 byte = addr & 0xff; 252 *--cp = byte % 10 + '0'; 253 byte /= 10; 254 if (byte > 0) { 255 *--cp = byte % 10 + '0'; 256 byte /= 10; 257 if (byte > 0) 258 *--cp = byte + '0'; 259 } 260 *--cp = '.'; 261 addr >>= 8; 262 } while (--n > 0); 263 264 return (cp+1); 265 } 266 267 static char * 268 number(char *s, n_long *n) 269 { 270 for (*n = 0; isdigit(*s); s++) 271 *n = (*n * 10) + *s - '0'; 272 return s; 273 } 274 275 n_long 276 ip_convertaddr(char *p) 277 { 278 #define IP_ANYADDR 0 279 n_long addr = 0, n; 280 281 if (p == NULL || *p == '\0') 282 return IP_ANYADDR; 283 p = number(p, &n); 284 addr |= (n << 24) & 0xff000000; 285 if (*p == '\0' || *p++ != '.') 286 return IP_ANYADDR; 287 p = number(p, &n); 288 addr |= (n << 16) & 0xff0000; 289 if (*p == '\0' || *p++ != '.') 290 return IP_ANYADDR; 291 p = number(p, &n); 292 addr |= (n << 8) & 0xff00; 293 if (*p == '\0' || *p++ != '.') 294 return IP_ANYADDR; 295 p = number(p, &n); 296 addr |= n & 0xff; 297 if (*p != '\0') 298 return IP_ANYADDR; 299 300 return htonl(addr); 301 } 302