lib/libstand/net.c

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