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. All advertising materials mentioning features or use of this software
  20  *    must display the following acknowledgement:
  21  *      This product includes software developed by the University of
  22  *      California, Lawrence Berkeley Laboratory and its contributors.
  23  * 4. Neither the name of the University nor the names of its contributors
  24  *    may be used to endorse or promote products derived from this software
  25  *    without specific prior written permission.
  26  *
  27  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  28  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  29  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  30  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  31  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  32  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  33  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  34  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  36  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  37  * SUCH DAMAGE.
  38  *
  39  * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp  (LBL)
  40  * $FreeBSD: src/lib/libstand/net.c,v 1.1.1.1.6.1 2000/04/15 03:09:28 ps Exp $
  41  * $DragonFly: src/lib/libstand/net.c,v 1.5 2005/12/11 02:27:26 swildner Exp $
  42  */
  43
  44 #include <sys/param.h>
  45 #include <sys/socket.h>
  46
  47 #include <string.h>
  48
  49 #include <net/if.h>
  50 #include <netinet/in.h>
  51 #include <netinet/if_ether.h>
  52 #include <netinet/in_systm.h>
  53
  54 #include <netinet/ip.h>
  55 #include <netinet/ip_var.h>
  56 #include <netinet/udp.h>
  57 #include <netinet/udp_var.h>
  58
  59 #include "stand.h"
  60 #include "net.h"
  61
  62 /*
  63  * Send a packet and wait for a reply, with exponential backoff.
  64  *
  65  * The send routine must return the actual number of bytes written,
  66  * or -1 on error.
  67  *
  68  * The receive routine can indicate success by returning the number of
  69  * bytes read; it can return 0 to indicate EOF; it can return -1 with a
  70  * non-zero errno to indicate failure; finally, it can return -1 with a
  71  * zero errno to indicate it isn't done yet.
  72  */
  73 ssize_t
  74 sendrecv(struct iodesc *d, ssize_t (*sproc)(struct iodesc *, void *, size_t),
  75          void *sbuf, size_t ssize,
  76          ssize_t (*rproc)(struct iodesc *, void *, size_t, time_t), void *rbuf,
  77          size_t rsize)
  78 {
  79         ssize_t cc;
  80         time_t t, tmo, tlast;
  81         long tleft;
  82
  83 #ifdef NET_DEBUG
  84         if (debug)
  85                 printf("sendrecv: called\n");
  86 #endif
  87
  88         tmo = MINTMO;
  89         tlast = tleft = 0;
  90         t = getsecs();
  91         for (;;) {
  92                 if (tleft <= 0) {
  93                         if (tmo >= MAXTMO) {
  94                                 errno = ETIMEDOUT;
  95                                 return -1;
  96                         }
  97                         cc = (*sproc)(d, sbuf, ssize);
  98                         if (cc != -1 && cc < ssize)
  99                                 panic("sendrecv: short write! (%d < %d)",
 100                                     cc, ssize);
 101
 102                         tleft = tmo;
 103                         tmo <<= 1;
 104                         if (tmo > MAXTMO)
 105                                 tmo = MAXTMO;
 106
 107                         if (cc == -1) {
 108                                 /* Error on transmit; wait before retrying */
 109                                 while ((getsecs() - t) < tmo);
 110                                 tleft = 0;
 111                                 continue;
 112                         }
 113
 114                         tlast = t;
 115                 }
 116
 117                 /* Try to get a packet and process it. */
 118                 cc = (*rproc)(d, rbuf, rsize, tleft);
 119                 /* Return on data, EOF or real error. */
 120                 if (cc != -1 || errno != 0)
 121                         return (cc);
 122
 123                 /* Timed out or didn't get the packet we're waiting for */
 124                 t = getsecs();
 125                 tleft -= t - tlast;
 126                 tlast = t;
 127         }
 128 }
 129
 130 /*
 131  * Like inet_addr() in the C library, but we only accept base-10.
 132  * Return values are in network order.
 133  */
 134 n_long
 135 inet_addr(char *cp)
 136 {
 137         u_long val;
 138         int n;
 139         char c;
 140         u_int parts[4];
 141         u_int *pp = parts;
 142
 143         for (;;) {
 144                 /*
 145                  * Collect number up to ``.''.
 146                  * Values are specified as for C:
 147                  * 0x=hex, 0=octal, other=decimal.
 148                  */
 149                 val = 0;
 150                 while ((c = *cp) != '\0') {
 151                         if (c >= '0' && c <= '9') {
 152                                 val = (val * 10) + (c - '0');
 153                                 cp++;
 154                                 continue;
 155                         }
 156                         break;
 157                 }
 158                 if (*cp == '.') {
 159                         /*
 160                          * Internet format:
 161                          *      a.b.c.d
 162                          *      a.b.c   (with c treated as 16-bits)
 163                          *      a.b     (with b treated as 24 bits)
 164                          */
 165                         if (pp >= parts + 3 || val > 0xff)
 166                                 goto bad;
 167                         *pp++ = val, cp++;
 168                 } else
 169                         break;
 170         }
 171         /*
 172          * Check for trailing characters.
 173          */
 174         if (*cp != '\0')
 175                 goto bad;
 176
 177         /*
 178          * Concoct the address according to
 179          * the number of parts specified.
 180          */
 181         n = pp - parts + 1;
 182         switch (n) {
 183
 184         case 1:                         /* a -- 32 bits */
 185                 break;
 186
 187         case 2:                         /* a.b -- 8.24 bits */
 188                 if (val > 0xffffff)
 189                         goto bad;
 190                 val |= parts[0] << 24;
 191                 break;
 192
 193         case 3:                         /* a.b.c -- 8.8.16 bits */
 194                 if (val > 0xffff)
 195                         goto bad;
 196                 val |= (parts[0] << 24) | (parts[1] << 16);
 197                 break;
 198
 199         case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
 200                 if (val > 0xff)
 201                         goto bad;
 202                 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 203                 break;
 204         }
 205
 206         return (htonl(val));
 207  bad:
 208         return (htonl(INADDR_NONE));
 209 }
 210
 211 char *
 212 inet_ntoa(struct in_addr ia)
 213 {
 214         return (intoa(ia.s_addr));
 215 }
 216
 217 /* Similar to inet_ntoa() */
 218 char *
 219 intoa(n_long addr)
 220 {
 221         char *cp;
 222         u_int byte;
 223         int n;
 224         static char buf[17];    /* strlen(".255.255.255.255") + 1 */
 225
 226         addr = ntohl(addr);
 227         cp = &buf[sizeof buf];
 228         *--cp = '\0';
 229
 230         n = 4;
 231         do {
 232                 byte = addr & 0xff;
 233                 *--cp = byte % 10 + '0';
 234                 byte /= 10;
 235                 if (byte > 0) {
 236                         *--cp = byte % 10 + '0';
 237                         byte /= 10;
 238                         if (byte > 0)
 239                                 *--cp = byte + '0';
 240                 }
 241                 *--cp = '.';
 242                 addr >>= 8;
 243         } while (--n > 0);
 244
 245         return (cp+1);
 246 }
 247
 248 static char *
 249 number(char *s, int *n)
 250 {
 251         for (*n = 0; isdigit(*s); s++)
 252                 *n = (*n * 10) + *s - '0';
 253         return s;
 254 }
 255
 256 n_long
 257 ip_convertaddr(char *p)
 258 {
 259 #define IP_ANYADDR      0
 260         n_long addr = 0, n;
 261
 262         if (p == NULL || *p == '\0')
 263                 return IP_ANYADDR;
 264         p = number(p, &n);
 265         addr |= (n << 24) & 0xff000000;
 266         if (*p == '\0' || *p++ != '.')
 267                 return IP_ANYADDR;
 268         p = number(p, &n);
 269         addr |= (n << 16) & 0xff0000;
 270         if (*p == '\0' || *p++ != '.')
 271                 return IP_ANYADDR;
 272         p = number(p, &n);
 273         addr |= (n << 8) & 0xff00;
 274         if (*p == '\0' || *p++ != '.')
 275                 return IP_ANYADDR;
 276         p = number(p, &n);
 277         addr |= n & 0xff;
 278         if (*p != '\0')
 279                 return IP_ANYADDR;
 280
 281         return htonl(addr);
 282 }