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/in_pcb.h> 52 #include <netinet/ip.h> 53 #include <netinet/ip_var.h> 54 #include <netinet/udp.h> 55 #include <netinet/udp_var.h> 56 57 #include "stand.h" 58 #include "net.h" 59 60 /* 61 * Maximum wait time for sending and receiving before we give up and timeout. 62 * If set to 0, operations will eventually timeout completely, but send/recv 63 * timeouts must progress exponentially from MINTMO to MAXTMO before final 64 * timeout is hit. 65 */ 66 #ifndef MAXWAIT 67 #define MAXWAIT 0 /* seconds */ 68 #endif 69 70 #if MAXWAIT < 0 71 #error MAXWAIT must not be a negative number 72 #endif 73 74 /* 75 * Send a packet and wait for a reply, with exponential backoff. 76 * 77 * The send routine must return the actual number of bytes written, 78 * or -1 on error. 79 * 80 * The receive routine can indicate success by returning the number of 81 * bytes read; it can return 0 to indicate EOF; it can return -1 with a 82 * non-zero errno to indicate failure; finally, it can return -1 with a 83 * zero errno to indicate it isn't done yet. 84 */ 85 ssize_t 86 sendrecv(struct iodesc *d, 87 ssize_t (*sproc)(struct iodesc *, void *, size_t), 88 void *sbuf, size_t ssize, 89 ssize_t (*rproc)(struct iodesc *, void **, void **, time_t, void *), 90 void **pkt, void **payload, void *recv_extra) 91 { 92 ssize_t cc; 93 time_t t, tmo, tlast; 94 time_t tref; 95 long tleft; 96 97 #ifdef NET_DEBUG 98 if (debug) 99 printf("sendrecv: called\n"); 100 #endif 101 102 tmo = MINTMO; 103 tlast = 0; 104 tleft = 0; 105 tref = getsecs(); 106 t = getsecs(); 107 for (;;) { 108 if (MAXWAIT > 0 && (getsecs() - tref) >= MAXWAIT) { 109 errno = ETIMEDOUT; 110 return -1; 111 } 112 if (tleft <= 0) { 113 if (tmo >= MAXTMO) { 114 errno = ETIMEDOUT; 115 return -1; 116 } 117 cc = (*sproc)(d, sbuf, ssize); 118 if (cc != -1 && cc < ssize) 119 panic("sendrecv: short write! (%zd < %zd)", 120 cc, ssize); 121 122 tleft = tmo; 123 tmo += MINTMO; 124 if (tmo > MAXTMO) 125 tmo = MAXTMO; 126 127 if (cc == -1) { 128 /* Error on transmit; wait before retrying */ 129 while ((getsecs() - t) < tmo) 130 ; 131 tleft = 0; 132 continue; 133 } 134 135 tlast = t; 136 } 137 138 /* Try to get a packet and process it. */ 139 cc = (*rproc)(d, pkt, payload, tleft, recv_extra); 140 /* Return on data, EOF or real error. */ 141 if (cc != -1 || (errno != 0 && errno != ETIMEDOUT)) 142 return (cc); 143 144 /* Timed out or didn't get the packet we're waiting for */ 145 t = getsecs(); 146 tleft -= t - tlast; 147 tlast = t; 148 } 149 } 150 151 /* 152 * Like inet_addr() in the C library, but we only accept base-10. 153 * Return values are in network order. 154 */ 155 n_long 156 inet_addr(char *cp) 157 { 158 u_long val; 159 int n; 160 char c; 161 u_int parts[4]; 162 u_int *pp = parts; 163 164 for (;;) { 165 /* 166 * Collect number up to ``.''. 167 * Values are specified as for C: 168 * 0x=hex, 0=octal, other=decimal. 169 */ 170 val = 0; 171 while ((c = *cp) != '\0') { 172 if (c >= '0' && c <= '9') { 173 val = (val * 10) + (c - '0'); 174 cp++; 175 continue; 176 } 177 break; 178 } 179 if (*cp == '.') { 180 /* 181 * Internet format: 182 * a.b.c.d 183 * a.b.c (with c treated as 16-bits) 184 * a.b (with b treated as 24 bits) 185 */ 186 if (pp >= parts + 3 || val > 0xff) 187 goto bad; 188 *pp++ = val, cp++; 189 } else 190 break; 191 } 192 /* 193 * Check for trailing characters. 194 */ 195 if (*cp != '\0') 196 goto bad; 197 198 /* 199 * Concoct the address according to 200 * the number of parts specified. 201 */ 202 n = pp - parts + 1; 203 switch (n) { 204 205 case 1: /* a -- 32 bits */ 206 break; 207 208 case 2: /* a.b -- 8.24 bits */ 209 if (val > 0xffffff) 210 goto bad; 211 val |= parts[0] << 24; 212 break; 213 214 case 3: /* a.b.c -- 8.8.16 bits */ 215 if (val > 0xffff) 216 goto bad; 217 val |= (parts[0] << 24) | (parts[1] << 16); 218 break; 219 220 case 4: /* a.b.c.d -- 8.8.8.8 bits */ 221 if (val > 0xff) 222 goto bad; 223 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8); 224 break; 225 } 226 227 return (htonl(val)); 228 bad: 229 return (htonl(INADDR_NONE)); 230 } 231 232 char * 233 inet_ntoa(struct in_addr ia) 234 { 235 return (intoa(ia.s_addr)); 236 } 237 238 /* Similar to inet_ntoa() */ 239 char * 240 intoa(n_long addr) 241 { 242 char *cp; 243 u_int byte; 244 int n; 245 static char buf[17]; /* strlen(".255.255.255.255") + 1 */ 246 247 addr = ntohl(addr); 248 cp = &buf[sizeof buf]; 249 *--cp = '\0'; 250 251 n = 4; 252 do { 253 byte = addr & 0xff; 254 *--cp = byte % 10 + '0'; 255 byte /= 10; 256 if (byte > 0) { 257 *--cp = byte % 10 + '0'; 258 byte /= 10; 259 if (byte > 0) 260 *--cp = byte + '0'; 261 } 262 *--cp = '.'; 263 addr >>= 8; 264 } while (--n > 0); 265 266 return (cp+1); 267 } 268 269 static char * 270 number(char *s, n_long *n) 271 { 272 for (*n = 0; isdigit(*s); s++) 273 *n = (*n * 10) + *s - '0'; 274 return s; 275 } 276 277 n_long 278 ip_convertaddr(char *p) 279 { 280 #define IP_ANYADDR 0 281 n_long addr = 0, n; 282 283 if (p == NULL || *p == '\0') 284 return IP_ANYADDR; 285 p = number(p, &n); 286 addr |= (n << 24) & 0xff000000; 287 if (*p == '\0' || *p++ != '.') 288 return IP_ANYADDR; 289 p = number(p, &n); 290 addr |= (n << 16) & 0xff0000; 291 if (*p == '\0' || *p++ != '.') 292 return IP_ANYADDR; 293 p = number(p, &n); 294 addr |= (n << 8) & 0xff00; 295 if (*p == '\0' || *p++ != '.') 296 return IP_ANYADDR; 297 p = number(p, &n); 298 addr |= n & 0xff; 299 if (*p != '\0') 300 return IP_ANYADDR; 301 302 return htonl(addr); 303 } 304