net/FreeBSD/inet_net_pton.c

   1 /*
   2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (c) 1996,1999 by Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 #if defined(LIBC_SCCS) && !defined(lint)
  19 static const char rcsid[] = "$Id: inet_net_pton.c,v 1.7.18.2 2008/08/26 04:42:43 marka Exp $";
  20 #endif
  21
  22 /* the algorithms only can deal with ASCII, so we optimize for it */
  23 #define USE_ASCII
  24
  25 #include <sys/cdefs.h>
  26 __FBSDID("$FreeBSD: src/lib/libc/inet/inet_net_pton.c,v 1.4 2008/12/14 19:39:53 ume Exp $");
  27
  28 #include "port_before.h"
  29
  30 #include <sys/types.h>
  31 #include <sys/socket.h>
  32 #include <netinet/in.h>
  33 #include <arpa/nameser.h>
  34 #include <arpa/inet.h>
  35
  36 #include <assert.h>
  37 #include <ctype.h>
  38 #include <errno.h>
  39 #include <stdio.h>
  40 #include <string.h>
  41 #include <stdlib.h>
  42
  43 #include "port_after.h"
  44
  45 #ifdef SPRINTF_CHAR
  46 # define SPRINTF(x) strlen(sprintf/**/x)
  47 #else
  48 # define SPRINTF(x) ((size_t)sprintf x)
  49 #endif
  50
  51 /*%
  52  * static int
  53  * inet_net_pton_ipv4(src, dst, size)
  54  *      convert IPv4 network number from presentation to network format.
  55  *      accepts hex octets, hex strings, decimal octets, and /CIDR.
  56  *      "size" is in bytes and describes "dst".
  57  * return:
  58  *      number of bits, either imputed classfully or specified with /CIDR,
  59  *      or -1 if some failure occurred (check errno).  ENOENT means it was
  60  *      not an IPv4 network specification.
  61  * note:
  62  *      network byte order assumed.  this means 192.5.5.240/28 has
  63  *      0b11110000 in its fourth octet.
  64  * author:
  65  *      Paul Vixie (ISC), June 1996
  66  */
  67 static int
  68 inet_net_pton_ipv4(const char *src, u_char *dst, size_t size) {
  69         static const char xdigits[] = "0123456789abcdef";
  70         static const char digits[] = "0123456789";
  71         int n, ch, tmp = 0, dirty, bits;
  72         const u_char *odst = dst;
  73
  74         ch = *src++;
  75         if (ch == '0' && (src[0] == 'x' || src[0] == 'X')
  76             && isascii((unsigned char)(src[1]))
  77             && isxdigit((unsigned char)(src[1]))) {
  78                 /* Hexadecimal: Eat nybble string. */
  79                 if (size <= 0U)
  80                         goto emsgsize;
  81                 dirty = 0;
  82                 src++;  /*%< skip x or X. */
  83                 while ((ch = *src++) != '\0' && isascii(ch) && isxdigit(ch)) {
  84                         if (isupper(ch))
  85                                 ch = tolower(ch);
  86                         n = strchr(xdigits, ch) - xdigits;
  87                         assert(n >= 0 && n <= 15);
  88                         if (dirty == 0)
  89                                 tmp = n;
  90                         else
  91                                 tmp = (tmp << 4) | n;
  92                         if (++dirty == 2) {
  93                                 if (size-- <= 0U)
  94                                         goto emsgsize;
  95                                 *dst++ = (u_char) tmp;
  96                                 dirty = 0;
  97                         }
  98                 }
  99                 if (dirty) {  /*%< Odd trailing nybble? */
 100                         if (size-- <= 0U)
 101                                 goto emsgsize;
 102                         *dst++ = (u_char) (tmp << 4);
 103                 }
 104         } else if (isascii(ch) && isdigit(ch)) {
 105                 /* Decimal: eat dotted digit string. */
 106                 for (;;) {
 107                         tmp = 0;
 108                         do {
 109                                 n = strchr(digits, ch) - digits;
 110                                 assert(n >= 0 && n <= 9);
 111                                 tmp *= 10;
 112                                 tmp += n;
 113                                 if (tmp > 255)
 114                                         goto enoent;
 115                         } while ((ch = *src++) != '\0' &&
 116                                  isascii(ch) && isdigit(ch));
 117                         if (size-- <= 0U)
 118                                 goto emsgsize;
 119                         *dst++ = (u_char) tmp;
 120                         if (ch == '\0' || ch == '/')
 121                                 break;
 122                         if (ch != '.')
 123                                 goto enoent;
 124                         ch = *src++;
 125                         if (!isascii(ch) || !isdigit(ch))
 126                                 goto enoent;
 127                 }
 128         } else
 129                 goto enoent;
 130
 131         bits = -1;
 132         if (ch == '/' && isascii((unsigned char)(src[0])) &&
 133             isdigit((unsigned char)(src[0])) && dst > odst) {
 134                 /* CIDR width specifier.  Nothing can follow it. */
 135                 ch = *src++;    /*%< Skip over the /. */
 136                 bits = 0;
 137                 do {
 138                         n = strchr(digits, ch) - digits;
 139                         assert(n >= 0 && n <= 9);
 140                         bits *= 10;
 141                         bits += n;
 142                         if (bits > 32)
 143                                 goto enoent;
 144                 } while ((ch = *src++) != '\0' && isascii(ch) && isdigit(ch));
 145                 if (ch != '\0')
 146                         goto enoent;
 147         }
 148
 149         /* Firey death and destruction unless we prefetched EOS. */
 150         if (ch != '\0')
 151                 goto enoent;
 152
 153         /* If nothing was written to the destination, we found no address. */
 154         if (dst == odst)
 155                 goto enoent;
 156         /* If no CIDR spec was given, infer width from net class. */
 157         if (bits == -1) {
 158                 if (*odst >= 240)       /*%< Class E */
 159                         bits = 32;
 160                 else if (*odst >= 224)  /*%< Class D */
 161                         bits = 8;
 162                 else if (*odst >= 192)  /*%< Class C */
 163                         bits = 24;
 164                 else if (*odst >= 128)  /*%< Class B */
 165                         bits = 16;
 166                 else                    /*%< Class A */
 167                         bits = 8;
 168                 /* If imputed mask is narrower than specified octets, widen. */
 169                 if (bits < ((dst - odst) * 8))
 170                         bits = (dst - odst) * 8;
 171                 /*
 172                  * If there are no additional bits specified for a class D
 173                  * address adjust bits to 4.
 174                  */
 175                 if (bits == 8 && *odst == 224)
 176                         bits = 4;
 177         }
 178         /* Extend network to cover the actual mask. */
 179         while (bits > ((dst - odst) * 8)) {
 180                 if (size-- <= 0U)
 181                         goto emsgsize;
 182                 *dst++ = '\0';
 183         }
 184         return (bits);
 185
 186  enoent:
 187         errno = ENOENT;
 188         return (-1);
 189
 190  emsgsize:
 191         errno = EMSGSIZE;
 192         return (-1);
 193 }
 194
 195 static int
 196 getbits(const char *src, int *bitsp) {
 197         static const char digits[] = "0123456789";
 198         int n;
 199         int val;
 200         char ch;
 201
 202         val = 0;
 203         n = 0;
 204         while ((ch = *src++) != '\0') {
 205                 const char *pch;
 206
 207                 pch = strchr(digits, ch);
 208                 if (pch != NULL) {
 209                         if (n++ != 0 && val == 0)       /*%< no leading zeros */
 210                                 return (0);
 211                         val *= 10;
 212                         val += (pch - digits);
 213                         if (val > 128)                  /*%< range */
 214                                 return (0);
 215                         continue;
 216                 }
 217                 return (0);
 218         }
 219         if (n == 0)
 220                 return (0);
 221         *bitsp = val;
 222         return (1);
 223 }
 224
 225 static int
 226 getv4(const char *src, u_char *dst, int *bitsp) {
 227         static const char digits[] = "0123456789";
 228         u_char *odst = dst;
 229         int n;
 230         u_int val;
 231         char ch;
 232
 233         val = 0;
 234         n = 0;
 235         while ((ch = *src++) != '\0') {
 236                 const char *pch;
 237
 238                 pch = strchr(digits, ch);
 239                 if (pch != NULL) {
 240                         if (n++ != 0 && val == 0)       /*%< no leading zeros */
 241                                 return (0);
 242                         val *= 10;
 243                         val += (pch - digits);
 244                         if (val > 255)                  /*%< range */
 245                                 return (0);
 246                         continue;
 247                 }
 248                 if (ch == '.' || ch == '/') {
 249                         if (dst - odst > 3)             /*%< too many octets? */
 250                                 return (0);
 251                         *dst++ = val;
 252                         if (ch == '/')
 253                                 return (getbits(src, bitsp));
 254                         val = 0;
 255                         n = 0;
 256                         continue;
 257                 }
 258                 return (0);
 259         }
 260         if (n == 0)
 261                 return (0);
 262         if (dst - odst > 3)             /*%< too many octets? */
 263                 return (0);
 264         *dst++ = val;
 265         return (1);
 266 }
 267
 268 static int
 269 inet_net_pton_ipv6(const char *src, u_char *dst, size_t size) {
 270         static const char xdigits_l[] = "0123456789abcdef",
 271                           xdigits_u[] = "0123456789ABCDEF";
 272         u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 273         const char *xdigits, *curtok;
 274         int ch, saw_xdigit;
 275         u_int val;
 276         int digits;
 277         int bits;
 278         size_t bytes;
 279         int words;
 280         int ipv4;
 281
 282         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 283         endp = tp + NS_IN6ADDRSZ;
 284         colonp = NULL;
 285         /* Leading :: requires some special handling. */
 286         if (*src == ':')
 287                 if (*++src != ':')
 288                         goto enoent;
 289         curtok = src;
 290         saw_xdigit = 0;
 291         val = 0;
 292         digits = 0;
 293         bits = -1;
 294         ipv4 = 0;
 295         while ((ch = *src++) != '\0') {
 296                 const char *pch;
 297
 298                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 299                         pch = strchr((xdigits = xdigits_u), ch);
 300                 if (pch != NULL) {
 301                         val <<= 4;
 302                         val |= (pch - xdigits);
 303                         if (++digits > 4)
 304                                 goto enoent;
 305                         saw_xdigit = 1;
 306                         continue;
 307                 }
 308                 if (ch == ':') {
 309                         curtok = src;
 310                         if (!saw_xdigit) {
 311                                 if (colonp)
 312                                         goto enoent;
 313                                 colonp = tp;
 314                                 continue;
 315                         } else if (*src == '\0')
 316                                 goto enoent;
 317                         if (tp + NS_INT16SZ > endp)
 318                                 return (0);
 319                         *tp++ = (u_char) (val >> 8) & 0xff;
 320                         *tp++ = (u_char) val & 0xff;
 321                         saw_xdigit = 0;
 322                         digits = 0;
 323                         val = 0;
 324                         continue;
 325                 }
 326                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 327                      getv4(curtok, tp, &bits) > 0) {
 328                         tp += NS_INADDRSZ;
 329                         saw_xdigit = 0;
 330                         ipv4 = 1;
 331                         break;  /*%< '\\0' was seen by inet_pton4(). */
 332                 }
 333                 if (ch == '/' && getbits(src, &bits) > 0)
 334                         break;
 335                 goto enoent;
 336         }
 337         if (saw_xdigit) {
 338                 if (tp + NS_INT16SZ > endp)
 339                         goto enoent;
 340                 *tp++ = (u_char) (val >> 8) & 0xff;
 341                 *tp++ = (u_char) val & 0xff;
 342         }
 343         if (bits == -1)
 344                 bits = 128;
 345
 346         words = (bits + 15) / 16;
 347         if (words < 2)
 348                 words = 2;
 349         if (ipv4)
 350                 words = 8;
 351         endp =  tmp + 2 * words;
 352
 353         if (colonp != NULL) {
 354                 /*
 355                  * Since some memmove()'s erroneously fail to handle
 356                  * overlapping regions, we'll do the shift by hand.
 357                  */
 358                 const int n = tp - colonp;
 359                 int i;
 360
 361                 if (tp == endp)
 362                         goto enoent;
 363                 for (i = 1; i <= n; i++) {
 364                         endp[- i] = colonp[n - i];
 365                         colonp[n - i] = 0;
 366                 }
 367                 tp = endp;
 368         }
 369         if (tp != endp)
 370                 goto enoent;
 371
 372         bytes = (bits + 7) / 8;
 373         if (bytes > size)
 374                 goto emsgsize;
 375         memcpy(dst, tmp, bytes);
 376         return (bits);
 377
 378  enoent:
 379         errno = ENOENT;
 380         return (-1);
 381
 382  emsgsize:
 383         errno = EMSGSIZE;
 384         return (-1);
 385 }
 386
 387 /*%
 388  * int
 389  * inet_net_pton(af, src, dst, size)
 390  *      convert network number from presentation to network format.
 391  *      accepts hex octets, hex strings, decimal octets, and /CIDR.
 392  *      "size" is in bytes and describes "dst".
 393  * return:
 394  *      number of bits, either imputed classfully or specified with /CIDR,
 395  *      or -1 if some failure occurred (check errno).  ENOENT means it was
 396  *      not a valid network specification.
 397  * author:
 398  *      Paul Vixie (ISC), June 1996
 399  */
 400 int
 401 inet_net_pton(int af, const char *src, void *dst, size_t size) {
 402         switch (af) {
 403         case AF_INET:
 404                 return (inet_net_pton_ipv4(src, dst, size));
 405         case AF_INET6:
 406                 return (inet_net_pton_ipv6(src, dst, size));
 407         default:
 408                 errno = EAFNOSUPPORT;
 409                 return (-1);
 410         }
 411 }
 412
 413 /*
 414  * Weak aliases for applications that use certain private entry points,
 415  * and fail to include <arpa/inet.h>.
 416  */
 417 #undef inet_net_pton
 418 __weak_reference(__inet_net_pton, inet_net_pton);
 419
 420 /*! \file */