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  * 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  * $FreeBSD: src/lib/libstand/net.c,v 1.1.1.1.6.1 2000/04/15 03:09:28 ps Exp $
  37  * $DragonFly: src/lib/libstand/net.c,v 1.5 2005/12/11 02:27:26 swildner Exp $
  38  */
  39
  40 #include <sys/param.h>
  41 #include <sys/socket.h>
  42
  43 #include <string.h>
  44
  45 #include <net/if.h>
  46 #include <netinet/in.h>
  47 #include <netinet/if_ether.h>
  48 #include <netinet/in_systm.h>
  49
  50 #include <netinet/ip.h>
  51 #include <netinet/ip_var.h>
  52 #include <netinet/udp.h>
  53 #include <netinet/udp_var.h>
  54
  55 #include "stand.h"
  56 #include "net.h"
  57
  58 /*
  59  * Send a packet and wait for a reply, with exponential backoff.
  60  *
  61  * The send routine must return the actual number of bytes written,
  62  * or -1 on error.
  63  *
  64  * The receive routine can indicate success by returning the number of
  65  * bytes read; it can return 0 to indicate EOF; it can return -1 with a
  66  * non-zero errno to indicate failure; finally, it can return -1 with a
  67  * zero errno to indicate it isn't done yet.
  68  */
  69 ssize_t
  70 sendrecv(struct iodesc *d, ssize_t (*sproc)(struct iodesc *, void *, size_t),
  71          void *sbuf, size_t ssize,
  72          ssize_t (*rproc)(struct iodesc *, void *, size_t, time_t), void *rbuf,
  73          size_t rsize)
  74 {
  75         ssize_t cc;
  76         time_t t, tmo, tlast;
  77         long tleft;
  78
  79 #ifdef NET_DEBUG
  80         if (debug)
  81                 printf("sendrecv: called\n");
  82 #endif
  83
  84         tmo = MINTMO;
  85         tlast = tleft = 0;
  86         t = getsecs();
  87         for (;;) {
  88                 if (tleft <= 0) {
  89                         if (tmo >= MAXTMO) {
  90                                 errno = ETIMEDOUT;
  91                                 return -1;
  92                         }
  93                         cc = (*sproc)(d, sbuf, ssize);
  94                         if (cc != -1 && cc < ssize)
  95                                 panic("sendrecv: short write! (%zd < %zu)",
  96                                     cc, ssize);
  97
  98                         tleft = tmo;
  99                         tmo <<= 1;
 100                         if (tmo > MAXTMO)
 101                                 tmo = MAXTMO;
 102
 103                         if (cc == -1) {
 104                                 /* Error on transmit; wait before retrying */
 105                                 while ((getsecs() - t) < tmo);
 106                                 tleft = 0;
 107                                 continue;
 108                         }
 109
 110                         tlast = t;
 111                 }
 112
 113                 /* Try to get a packet and process it. */
 114                 cc = (*rproc)(d, rbuf, rsize, tleft);
 115                 /* Return on data, EOF or real error. */
 116                 if (cc != -1 || errno != 0)
 117                         return (cc);
 118
 119                 /* Timed out or didn't get the packet we're waiting for */
 120                 t = getsecs();
 121                 tleft -= t - tlast;
 122                 tlast = t;
 123         }
 124 }
 125
 126 /*
 127  * Like inet_addr() in the C library, but we only accept base-10.
 128  * Return values are in network order.
 129  */
 130 n_long
 131 inet_addr(char *cp)
 132 {
 133         u_long val;
 134         int n;
 135         char c;
 136         u_int parts[4];
 137         u_int *pp = parts;
 138
 139         for (;;) {
 140                 /*
 141                  * Collect number up to ``.''.
 142                  * Values are specified as for C:
 143                  * 0x=hex, 0=octal, other=decimal.
 144                  */
 145                 val = 0;
 146                 while ((c = *cp) != '\0') {
 147                         if (c >= '0' && c <= '9') {
 148                                 val = (val * 10) + (c - '0');
 149                                 cp++;
 150                                 continue;
 151                         }
 152                         break;
 153                 }
 154                 if (*cp == '.') {
 155                         /*
 156                          * Internet format:
 157                          *      a.b.c.d
 158                          *      a.b.c   (with c treated as 16-bits)
 159                          *      a.b     (with b treated as 24 bits)
 160                          */
 161                         if (pp >= parts + 3 || val > 0xff)
 162                                 goto bad;
 163                         *pp++ = val, cp++;
 164                 } else
 165                         break;
 166         }
 167         /*
 168          * Check for trailing characters.
 169          */
 170         if (*cp != '\0')
 171                 goto bad;
 172
 173         /*
 174          * Concoct the address according to
 175          * the number of parts specified.
 176          */
 177         n = pp - parts + 1;
 178         switch (n) {
 179
 180         case 1:                         /* a -- 32 bits */
 181                 break;
 182
 183         case 2:                         /* a.b -- 8.24 bits */
 184                 if (val > 0xffffff)
 185                         goto bad;
 186                 val |= parts[0] << 24;
 187                 break;
 188
 189         case 3:                         /* a.b.c -- 8.8.16 bits */
 190                 if (val > 0xffff)
 191                         goto bad;
 192                 val |= (parts[0] << 24) | (parts[1] << 16);
 193                 break;
 194
 195         case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
 196                 if (val > 0xff)
 197                         goto bad;
 198                 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 199                 break;
 200         }
 201
 202         return (htonl(val));
 203  bad:
 204         return (htonl(INADDR_NONE));
 205 }
 206
 207 char *
 208 inet_ntoa(struct in_addr ia)
 209 {
 210         return (intoa(ia.s_addr));
 211 }
 212
 213 /* Similar to inet_ntoa() */
 214 char *
 215 intoa(n_long addr)
 216 {
 217         char *cp;
 218         u_int byte;
 219         int n;
 220         static char buf[17];    /* strlen(".255.255.255.255") + 1 */
 221
 222         addr = ntohl(addr);
 223         cp = &buf[sizeof buf];
 224         *--cp = '\0';
 225
 226         n = 4;
 227         do {
 228                 byte = addr & 0xff;
 229                 *--cp = byte % 10 + '0';
 230                 byte /= 10;
 231                 if (byte > 0) {
 232                         *--cp = byte % 10 + '0';
 233                         byte /= 10;
 234                         if (byte > 0)
 235                                 *--cp = byte + '0';
 236                 }
 237                 *--cp = '.';
 238                 addr >>= 8;
 239         } while (--n > 0);
 240
 241         return (cp+1);
 242 }
 243
 244 static char *
 245 number(char *s, int *n)
 246 {
 247         for (*n = 0; isdigit(*s); s++)
 248                 *n = (*n * 10) + *s - '0';
 249         return s;
 250 }
 251
 252 n_long
 253 ip_convertaddr(char *p)
 254 {
 255 #define IP_ANYADDR      0
 256         n_long addr = 0, n;
 257
 258         if (p == NULL || *p == '\0')
 259                 return IP_ANYADDR;
 260         p = number(p, &n);
 261         addr |= (n << 24) & 0xff000000;
 262         if (*p == '\0' || *p++ != '.')
 263                 return IP_ANYADDR;
 264         p = number(p, &n);
 265         addr |= (n << 16) & 0xff0000;
 266         if (*p == '\0' || *p++ != '.')
 267                 return IP_ANYADDR;
 268         p = number(p, &n);
 269         addr |= (n << 8) & 0xff00;
 270         if (*p == '\0' || *p++ != '.')
 271                 return IP_ANYADDR;
 272         p = number(p, &n);
 273         addr |= n & 0xff;
 274         if (*p != '\0')
 275                 return IP_ANYADDR;
 276
 277         return htonl(addr);
 278 }