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 = getsecs(); 105 t = getsecs(); 106 for (;;) { 107 if (MAXWAIT > 0 && (getsecs() - tref) >= MAXWAIT) { 108 errno = ETIMEDOUT; 109 return -1; 110 } 111 if (tleft <= 0) { 112 if (tmo >= MAXTMO) { 113 errno = ETIMEDOUT; 114 return -1; 115 } 116 cc = (*sproc)(d, sbuf, ssize); 117 if (cc != -1 && cc < ssize) 118 panic("sendrecv: short write! (%zd < %zd)", 119 cc, ssize); 120 121 tleft = tmo; 122 tmo += MINTMO; 123 if (tmo > MAXTMO) 124 tmo = MAXTMO; 125 126 if (cc == -1) { 127 /* Error on transmit; wait before retrying */ 128 while ((getsecs() - t) < tmo) 129 ; 130 tleft = 0; 131 continue; 132 } 133 134 tlast = t; 135 } 136 137 /* Try to get a packet and process it. */ 138 cc = (*rproc)(d, pkt, payload, tleft, recv_extra); 139 /* Return on data, EOF or real error. */ 140 if (cc != -1 || (errno != 0 && errno != ETIMEDOUT)) 141 return (cc); 142 143 /* Timed out or didn't get the packet we're waiting for */ 144 t = getsecs(); 145 tleft -= t - tlast; 146 tlast = t; 147 } 148 } 149 150 /* 151 * Like inet_addr() in the C library, but we only accept base-10. 152 * Return values are in network order. 153 */ 154 n_long 155 inet_addr(char *cp) 156 { 157 u_long val; 158 int n; 159 char c; 160 u_int parts[4]; 161 u_int *pp = parts; 162 163 for (;;) { 164 /* 165 * Collect number up to ``.''. 166 * Values are specified as for C: 167 * 0x=hex, 0=octal, other=decimal. 168 */ 169 val = 0; 170 while ((c = *cp) != '\0') { 171 if (c >= '0' && c <= '9') { 172 val = (val * 10) + (c - '0'); 173 cp++; 174 continue; 175 } 176 break; 177 } 178 if (*cp == '.') { 179 /* 180 * Internet format: 181 * a.b.c.d 182 * a.b.c (with c treated as 16-bits) 183 * a.b (with b treated as 24 bits) 184 */ 185 if (pp >= parts + 3 || val > 0xff) 186 goto bad; 187 *pp++ = val, cp++; 188 } else 189 break; 190 } 191 /* 192 * Check for trailing characters. 193 */ 194 if (*cp != '\0') 195 goto bad; 196 197 /* 198 * Concoct the address according to 199 * the number of parts specified. 200 */ 201 n = pp - parts + 1; 202 switch (n) { 203 204 case 1: /* a -- 32 bits */ 205 break; 206 207 case 2: /* a.b -- 8.24 bits */ 208 if (val > 0xffffff) 209 goto bad; 210 val |= parts[0] << 24; 211 break; 212 213 case 3: /* a.b.c -- 8.8.16 bits */ 214 if (val > 0xffff) 215 goto bad; 216 val |= (parts[0] << 24) | (parts[1] << 16); 217 break; 218 219 case 4: /* a.b.c.d -- 8.8.8.8 bits */ 220 if (val > 0xff) 221 goto bad; 222 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); 223 break; 224 } 225 226 return (htonl(val)); 227 bad: 228 return (htonl(INADDR_NONE)); 229 } 230 231 char * 232 inet_ntoa(struct in_addr ia) 233 { 234 return (intoa(ia.s_addr)); 235 } 236 237 /* Similar to inet_ntoa() */ 238 char * 239 intoa(n_long addr) 240 { 241 char *cp; 242 u_int byte; 243 int n; 244 static char buf[17]; /* strlen(".255.255.255.255") + 1 */ 245 246 addr = ntohl(addr); 247 cp = &buf[sizeof buf]; 248 *--cp = '\0'; 249 250 n = 4; 251 do { 252 byte = addr & 0xff; 253 *--cp = byte % 10 + '0'; 254 byte /= 10; 255 if (byte > 0) { 256 *--cp = byte % 10 + '0'; 257 byte /= 10; 258 if (byte > 0) 259 *--cp = byte + '0'; 260 } 261 *--cp = '.'; 262 addr >>= 8; 263 } while (--n > 0); 264 265 return (cp+1); 266 } 267 268 static char * 269 number(char *s, n_long *n) 270 { 271 for (*n = 0; isdigit(*s); s++) 272 *n = (*n * 10) + *s - '0'; 273 return s; 274 } 275 276 n_long 277 ip_convertaddr(char *p) 278 { 279 #define IP_ANYADDR 0 280 n_long addr = 0, n; 281 282 if (p == NULL || *p == '\0') 283 return IP_ANYADDR; 284 p = number(p, &n); 285 addr |= (n << 24) & 0xff000000; 286 if (*p == '\0' || *p++ != '.') 287 return IP_ANYADDR; 288 p = number(p, &n); 289 addr |= (n << 16) & 0xff0000; 290 if (*p == '\0' || *p++ != '.') 291 return IP_ANYADDR; 292 p = number(p, &n); 293 addr |= (n << 8) & 0xff00; 294 if (*p == '\0' || *p++ != '.') 295 return IP_ANYADDR; 296 p = number(p, &n); 297 addr |= n & 0xff; 298 if (*p != '\0') 299 return IP_ANYADDR; 300 301 return htonl(addr); 302 } 303