contrib/bind-9.2.4rc7/lib/bind/inet/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 1.4.2.3 2004/03/17 00:40:11 marka Exp $";
  20 #endif
  21
  22 #include "port_before.h"
  23
  24 #include <sys/types.h>
  25 #include <sys/socket.h>
  26 #include <netinet/in.h>
  27 #include <arpa/nameser.h>
  28 #include <arpa/inet.h>
  29
  30 #include <isc/assertions.h>
  31 #include <ctype.h>
  32 #include <errno.h>
  33 #include <stdio.h>
  34 #include <string.h>
  35 #include <stdlib.h>
  36
  37 #include "port_after.h"
  38
  39 #ifdef SPRINTF_CHAR
  40 # define SPRINTF(x) strlen(sprintf/**/x)
  41 #else
  42 # define SPRINTF(x) ((size_t)sprintf x)
  43 #endif
  44
  45 /*
  46  * static int
  47  * inet_net_pton_ipv4(src, dst, size)
  48  *      convert IPv4 network number from presentation to network format.
  49  *      accepts hex octets, hex strings, decimal octets, and /CIDR.
  50  *      "size" is in bytes and describes "dst".
  51  * return:
  52  *      number of bits, either imputed classfully or specified with /CIDR,
  53  *      or -1 if some failure occurred (check errno).  ENOENT means it was
  54  *      not an IPv4 network specification.
  55  * note:
  56  *      network byte order assumed.  this means 192.5.5.240/28 has
  57  *      0b11110000 in its fourth octet.
  58  * author:
  59  *      Paul Vixie (ISC), June 1996
  60  */
  61 static int
  62 inet_net_pton_ipv4(const char *src, u_char *dst, size_t size) {
  63         static const char xdigits[] = "0123456789abcdef";
  64         static const char digits[] = "0123456789";
  65         int n, ch, tmp = 0, dirty, bits;
  66         const u_char *odst = dst;
  67
  68         ch = *src++;
  69         if (ch == '0' && (src[0] == 'x' || src[0] == 'X')
  70             && isascii((unsigned char)(src[1]))
  71             && isxdigit((unsigned char)(src[1]))) {
  72                 /* Hexadecimal: Eat nybble string. */
  73                 if (size <= 0U)
  74                         goto emsgsize;
  75                 dirty = 0;
  76                 src++;  /* skip x or X. */
  77                 while ((ch = *src++) != '\0' && isascii(ch) && isxdigit(ch)) {
  78                         if (isupper(ch))
  79                                 ch = tolower(ch);
  80                         n = strchr(xdigits, ch) - xdigits;
  81                         INSIST(n >= 0 && n <= 15);
  82                         if (dirty == 0)
  83                                 tmp = n;
  84                         else
  85                                 tmp = (tmp << 4) | n;
  86                         if (++dirty == 2) {
  87                                 if (size-- <= 0U)
  88                                         goto emsgsize;
  89                                 *dst++ = (u_char) tmp;
  90                                 dirty = 0;
  91                         }
  92                 }
  93                 if (dirty) {  /* Odd trailing nybble? */
  94                         if (size-- <= 0U)
  95                                 goto emsgsize;
  96                         *dst++ = (u_char) (tmp << 4);
  97                 }
  98         } else if (isascii(ch) && isdigit(ch)) {
  99                 /* Decimal: eat dotted digit string. */
 100                 for (;;) {
 101                         tmp = 0;
 102                         do {
 103                                 n = strchr(digits, ch) - digits;
 104                                 INSIST(n >= 0 && n <= 9);
 105                                 tmp *= 10;
 106                                 tmp += n;
 107                                 if (tmp > 255)
 108                                         goto enoent;
 109                         } while ((ch = *src++) != '\0' &&
 110                                  isascii(ch) && isdigit(ch));
 111                         if (size-- <= 0U)
 112                                 goto emsgsize;
 113                         *dst++ = (u_char) tmp;
 114                         if (ch == '\0' || ch == '/')
 115                                 break;
 116                         if (ch != '.')
 117                                 goto enoent;
 118                         ch = *src++;
 119                         if (!isascii(ch) || !isdigit(ch))
 120                                 goto enoent;
 121                 }
 122         } else
 123                 goto enoent;
 124
 125         bits = -1;
 126         if (ch == '/' && isascii((unsigned char)(src[0])) &&
 127             isdigit((unsigned char)(src[0])) && dst > odst) {
 128                 /* CIDR width specifier.  Nothing can follow it. */
 129                 ch = *src++;    /* Skip over the /. */
 130                 bits = 0;
 131                 do {
 132                         n = strchr(digits, ch) - digits;
 133                         INSIST(n >= 0 && n <= 9);
 134                         bits *= 10;
 135                         bits += n;
 136                 } while ((ch = *src++) != '\0' && isascii(ch) && isdigit(ch));
 137                 if (ch != '\0')
 138                         goto enoent;
 139                 if (bits > 32)
 140                         goto emsgsize;
 141         }
 142
 143         /* Firey death and destruction unless we prefetched EOS. */
 144         if (ch != '\0')
 145                 goto enoent;
 146
 147         /* If nothing was written to the destination, we found no address. */
 148         if (dst == odst)
 149                 goto enoent;
 150         /* If no CIDR spec was given, infer width from net class. */
 151         if (bits == -1) {
 152                 if (*odst >= 240)       /* Class E */
 153                         bits = 32;
 154                 else if (*odst >= 224)  /* Class D */
 155                         bits = 8;
 156                 else if (*odst >= 192)  /* Class C */
 157                         bits = 24;
 158                 else if (*odst >= 128)  /* Class B */
 159                         bits = 16;
 160                 else                    /* Class A */
 161                         bits = 8;
 162                 /* If imputed mask is narrower than specified octets, widen. */
 163                 if (bits < ((dst - odst) * 8))
 164                         bits = (dst - odst) * 8;
 165                 /*
 166                  * If there are no additional bits specified for a class D
 167                  * address adjust bits to 4.
 168                  */
 169                 if (bits == 8 && *odst == 224)
 170                         bits = 4;
 171         }
 172         /* Extend network to cover the actual mask. */
 173         while (bits > ((dst - odst) * 8)) {
 174                 if (size-- <= 0U)
 175                         goto emsgsize;
 176                 *dst++ = '\0';
 177         }
 178         return (bits);
 179
 180  enoent:
 181         errno = ENOENT;
 182         return (-1);
 183
 184  emsgsize:
 185         errno = EMSGSIZE;
 186         return (-1);
 187 }
 188
 189 static int
 190 getbits(const char *src, int *bitsp) {
 191         static const char digits[] = "0123456789";
 192         int n;
 193         int val;
 194         char ch;
 195
 196         val = 0;
 197         n = 0;
 198         while ((ch = *src++) != '\0') {
 199                 const char *pch;
 200
 201                 pch = strchr(digits, ch);
 202                 if (pch != NULL) {
 203                         if (n++ != 0 && val == 0)       /* no leading zeros */
 204                                 return (0);
 205                         val *= 10;
 206                         val += (pch - digits);
 207                         if (val > 128)                  /* range */
 208                                 return (0);
 209                         continue;
 210                 }
 211                 return (0);
 212         }
 213         if (n == 0)
 214                 return (0);
 215         *bitsp = val;
 216         return (1);
 217 }
 218
 219 static int
 220 getv4(const char *src, u_char *dst, int *bitsp) {
 221         static const char digits[] = "0123456789";
 222         u_char *odst = dst;
 223         int n;
 224         u_int val;
 225         char ch;
 226
 227         val = 0;
 228         n = 0;
 229         while ((ch = *src++) != '\0') {
 230                 const char *pch;
 231
 232                 pch = strchr(digits, ch);
 233                 if (pch != NULL) {
 234                         if (n++ != 0 && val == 0)       /* no leading zeros */
 235                                 return (0);
 236                         val *= 10;
 237                         val += (pch - digits);
 238                         if (val > 255)                  /* range */
 239                                 return (0);
 240                         continue;
 241                 }
 242                 if (ch == '.' || ch == '/') {
 243                         if (dst - odst > 3)             /* too many octets? */
 244                                 return (0);
 245                         *dst++ = val;
 246                         if (ch == '/')
 247                                 return (getbits(src, bitsp));
 248                         val = 0;
 249                         n = 0;
 250                         continue;
 251                 }
 252                 return (0);
 253         }
 254         if (n == 0)
 255                 return (0);
 256         if (dst - odst > 3)             /* too many octets? */
 257                 return (0);
 258         *dst++ = val;
 259         return (1);
 260 }
 261
 262 static int
 263 inet_net_pton_ipv6(const char *src, u_char *dst, size_t size) {
 264         static const char xdigits_l[] = "0123456789abcdef",
 265                           xdigits_u[] = "0123456789ABCDEF";
 266         u_char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
 267         const char *xdigits, *curtok;
 268         int ch, saw_xdigit;
 269         u_int val;
 270         int digits;
 271         int bits;
 272         size_t bytes;
 273         int words;
 274         int ipv4;
 275
 276         memset((tp = tmp), '\0', NS_IN6ADDRSZ);
 277         endp = tp + NS_IN6ADDRSZ;
 278         colonp = NULL;
 279         /* Leading :: requires some special handling. */
 280         if (*src == ':')
 281                 if (*++src != ':')
 282                         goto enoent;
 283         curtok = src;
 284         saw_xdigit = 0;
 285         val = 0;
 286         digits = 0;
 287         bits = -1;
 288         ipv4 = 0;
 289         while ((ch = *src++) != '\0') {
 290                 const char *pch;
 291
 292                 if ((pch = strchr((xdigits = xdigits_l), ch)) == NULL)
 293                         pch = strchr((xdigits = xdigits_u), ch);
 294                 if (pch != NULL) {
 295                         val <<= 4;
 296                         val |= (pch - xdigits);
 297                         if (++digits > 4)
 298                                 goto enoent;
 299                         saw_xdigit = 1;
 300                         continue;
 301                 }
 302                 if (ch == ':') {
 303                         curtok = src;
 304                         if (!saw_xdigit) {
 305                                 if (colonp)
 306                                         goto enoent;
 307                                 colonp = tp;
 308                                 continue;
 309                         } else if (*src == '\0')
 310                                 goto enoent;
 311                         if (tp + NS_INT16SZ > endp)
 312                                 return (0);
 313                         *tp++ = (u_char) (val >> 8) & 0xff;
 314                         *tp++ = (u_char) val & 0xff;
 315                         saw_xdigit = 0;
 316                         digits = 0;
 317                         val = 0;
 318                         continue;
 319                 }
 320                 if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
 321                      getv4(curtok, tp, &bits) > 0) {
 322                         tp += NS_INADDRSZ;
 323                         saw_xdigit = 0;
 324                         ipv4 = 1;
 325                         break;  /* '\0' was seen by inet_pton4(). */
 326                 }
 327                 if (ch == '/' && getbits(src, &bits) > 0)
 328                         break;
 329                 goto enoent;
 330         }
 331         if (saw_xdigit) {
 332                 if (tp + NS_INT16SZ > endp)
 333                         goto enoent;
 334                 *tp++ = (u_char) (val >> 8) & 0xff;
 335                 *tp++ = (u_char) val & 0xff;
 336         }
 337         if (bits == -1)
 338                 bits = 128;
 339
 340         words = (bits + 15) / 16;
 341         if (words < 2)
 342                 words = 2;
 343         if (ipv4)
 344                 words = 8;
 345         endp =  tmp + 2 * words;
 346
 347         if (colonp != NULL) {
 348                 /*
 349                  * Since some memmove()'s erroneously fail to handle
 350                  * overlapping regions, we'll do the shift by hand.
 351                  */
 352                 const int n = tp - colonp;
 353                 int i;
 354
 355                 if (tp == endp)
 356                         goto enoent;
 357                 for (i = 1; i <= n; i++) {
 358                         endp[- i] = colonp[n - i];
 359                         colonp[n - i] = 0;
 360                 }
 361                 tp = endp;
 362         }
 363         if (tp != endp)
 364                 goto enoent;
 365
 366         bytes = (bits + 7) / 8;
 367         if (bytes > size)
 368                 goto emsgsize;
 369         memcpy(dst, tmp, bytes);
 370         return (bits);
 371
 372  enoent:
 373         errno = ENOENT;
 374         return (-1);
 375
 376  emsgsize:
 377         errno = EMSGSIZE;
 378         return (-1);
 379 }
 380
 381 /*
 382  * int
 383  * inet_net_pton(af, src, dst, size)
 384  *      convert network number from presentation to network format.
 385  *      accepts hex octets, hex strings, decimal octets, and /CIDR.
 386  *      "size" is in bytes and describes "dst".
 387  * return:
 388  *      number of bits, either imputed classfully or specified with /CIDR,
 389  *      or -1 if some failure occurred (check errno).  ENOENT means it was
 390  *      not a valid network specification.
 391  * author:
 392  *      Paul Vixie (ISC), June 1996
 393  */
 394 int
 395 inet_net_pton(int af, const char *src, void *dst, size_t size) {
 396         switch (af) {
 397         case AF_INET:
 398                 return (inet_net_pton_ipv4(src, dst, size));
 399         case AF_INET6:
 400                 return (inet_net_pton_ipv6(src, dst, size));
 401         default:
 402                 errno = EAFNOSUPPORT;
 403                 return (-1);
 404         }
 405 }