usr/src/boot/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
  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  * Maximum wait time for sending and receiving before we give up and timeout.
  60  * If set to 0, operations will eventually timeout completely, but send/recv
  61  * timeouts must progress exponentially from MINTMO to MAXTMO before final
  62  * timeout is hit.
  63  */
  64 #ifndef MAXWAIT
  65 #define MAXWAIT 0       /* seconds */
  66 #endif
  67
  68 #if MAXWAIT < 0
  69 #error MAXWAIT must not be a negative number
  70 #endif
  71
  72 /*
  73  * Send a packet and wait for a reply, with exponential backoff.
  74  *
  75  * The send routine must return the actual number of bytes written,
  76  * or -1 on error.
  77  *
  78  * The receive routine can indicate success by returning the number of
  79  * bytes read; it can return 0 to indicate EOF; it can return -1 with a
  80  * non-zero errno to indicate failure; finally, it can return -1 with a
  81  * zero errno to indicate it isn't done yet.
  82  */
  83 ssize_t
  84 sendrecv(struct iodesc *d,
  85     ssize_t (*sproc)(struct iodesc *, void *, size_t),
  86     void *sbuf, size_t ssize,
  87     ssize_t (*rproc)(struct iodesc *, void **, void**, time_t, void *),
  88     void **pkt, void **payload, void *recv_extra)
  89 {
  90         ssize_t cc;
  91         time_t t, tmo, tlast;
  92         time_t tref;
  93         long tleft;
  94
  95 #ifdef NET_DEBUG
  96         if (debug)
  97                 printf("sendrecv: called\n");
  98 #endif
  99
 100         tmo = MINTMO;
 101         tlast = 0;
 102         tleft = 0;
 103         tref = getsecs();
 104         t = getsecs();
 105         for (;;) {
 106                 if (MAXWAIT > 0 && (getsecs() - tref) >= MAXWAIT) {
 107                         errno = ETIMEDOUT;
 108                         return (-1);
 109                 }
 110                 if (tleft <= 0) {
 111                         if (tmo >= MAXTMO) {
 112                                 errno = ETIMEDOUT;
 113                                 return (-1);
 114                         }
 115                         cc = (*sproc)(d, sbuf, ssize);
 116                         if (cc != -1 && cc < ssize)
 117                                 panic("sendrecv: short write! (%zd < %zd)",
 118                                     cc, ssize);
 119
 120                         tleft = tmo;
 121                         tmo += MINTMO;
 122                         if (tmo > MAXTMO)
 123                                 tmo = MAXTMO;
 124
 125                         if (cc == -1) {
 126                                 /* Error on transmit; wait before retrying */
 127                                 while ((getsecs() - t) < tmo)
 128                                         ;
 129                                 tleft = 0;
 130                                 continue;
 131                         }
 132
 133                         tlast = t;
 134                 }
 135
 136                 /* Try to get a packet and process it. */
 137                 cc = (*rproc)(d, pkt, payload, tleft, recv_extra);
 138                 /* Return on data, EOF or real error. */
 139                 if (cc != -1 || (errno != 0 && errno != ETIMEDOUT))
 140                         return (cc);
 141
 142                 /* Timed out or didn't get the packet we're waiting for */
 143                 t = getsecs();
 144                 tleft -= t - tlast;
 145                 tlast = t;
 146         }
 147 }
 148
 149 /*
 150  * Like inet_addr() in the C library, but we only accept base-10.
 151  * Return values are in network order.
 152  */
 153 n_long
 154 inet_addr(char *cp)
 155 {
 156         unsigned long val;
 157         int n;
 158         char c;
 159         unsigned int parts[4];
 160         unsigned int *pp = parts;
 161
 162         for (;;) {
 163                 /*
 164                  * Collect number up to ``.''.
 165                  * Values are specified as for C:
 166                  * 0x=hex, 0=octal, other=decimal.
 167                  */
 168                 val = 0;
 169                 while ((c = *cp) != '\0') {
 170                         if (c >= '0' && c <= '9') {
 171                                 val = (val * 10) + (c - '0');
 172                                 cp++;
 173                                 continue;
 174                         }
 175                         break;
 176                 }
 177                 if (*cp == '.') {
 178                         /*
 179                          * Internet format:
 180                          *      a.b.c.d
 181                          *      a.b.c   (with c treated as 16-bits)
 182                          *      a.b     (with b treated as 24 bits)
 183                          */
 184                         if (pp >= parts + 3 || val > 0xff)
 185                                 goto bad;
 186                         *pp++ = val, cp++;
 187                 } else
 188                         break;
 189         }
 190         /*
 191          * Check for trailing characters.
 192          */
 193         if (*cp != '\0')
 194                 goto bad;
 195
 196         /*
 197          * Concoct the address according to
 198          * the number of parts specified.
 199          */
 200         n = pp - parts + 1;
 201         switch (n) {
 202
 203         case 1:                         /* a -- 32 bits */
 204                 break;
 205
 206         case 2:                         /* a.b -- 8.24 bits */
 207                 if (val > 0xffffff)
 208                         goto bad;
 209                 val |= parts[0] << 24;
 210                 break;
 211
 212         case 3:                         /* a.b.c -- 8.8.16 bits */
 213                 if (val > 0xffff)
 214                         goto bad;
 215                 val |= (parts[0] << 24) | (parts[1] << 16);
 216                 break;
 217
 218         case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
 219                 if (val > 0xff)
 220                         goto bad;
 221                 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 222                 break;
 223         }
 224
 225         return (htonl(val));
 226 bad:
 227         return (htonl(INADDR_NONE));
 228 }
 229
 230 char *
 231 inet_ntoa(struct in_addr ia)
 232 {
 233         return (intoa(ia.s_addr));
 234 }
 235
 236 /* Similar to inet_ntoa() */
 237 char *
 238 intoa(n_long addr)
 239 {
 240         char *cp;
 241         unsigned int byte;
 242         int n;
 243         static char buf[17];    /* strlen(".255.255.255.255") + 1 */
 244
 245         addr = ntohl(addr);
 246         cp = &buf[sizeof (buf)];
 247         *--cp = '\0';
 248
 249         n = 4;
 250         do {
 251                 byte = addr & 0xff;
 252                 *--cp = byte % 10 + '0';
 253                 byte /= 10;
 254                 if (byte > 0) {
 255                         *--cp = byte % 10 + '0';
 256                         byte /= 10;
 257                         if (byte > 0)
 258                                 *--cp = byte + '0';
 259                 }
 260                 *--cp = '.';
 261                 addr >>= 8;
 262         } while (--n > 0);
 263
 264         return (cp+1);
 265 }
 266
 267 static char *
 268 number(char *s, uint32_t *n)
 269 {
 270         for (*n = 0; isdigit(*s); s++)
 271                 *n = (*n * 10) + *s - '0';
 272         return (s);
 273 }
 274
 275 n_long
 276 ip_convertaddr(char *p)
 277 {
 278 #define IP_ANYADDR      0
 279         uint32_t addr = 0, n;
 280
 281         if (p == NULL || *p == '\0')
 282                 return (IP_ANYADDR);
 283         p = number(p, &n);
 284         addr |= (n << 24) & 0xff000000;
 285         if (*p == '\0' || *p++ != '.')
 286                 return (IP_ANYADDR);
 287         p = number(p, &n);
 288         addr |= (n << 16) & 0xff0000;
 289         if (*p == '\0' || *p++ != '.')
 290                 return (IP_ANYADDR);
 291         p = number(p, &n);
 292         addr |= (n << 8) & 0xff00;
 293         if (*p == '\0' || *p++ != '.')
 294                 return (IP_ANYADDR);
 295         p = number(p, &n);
 296         addr |= n & 0xff;
 297         if (*p != '\0')
 298                 return (IP_ANYADDR);
 299
 300         return (htonl(addr));
 301 }