root/opal/mca/hwloc/hwloc201/hwloc/hwloc/base64.c

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DEFINITIONS

This source file includes following definitions.
  1. hwloc_encode_to_base64
  2. hwloc_decode_from_base64

   1 /*
   2  * Copyright © 2012-2018 Inria.  All rights reserved.
   3  * See COPYING in top-level directory.
   4  *
   5  * Modifications after import:
   6  * - removed all #if
   7  * - updated prototypes
   8  * - updated #include
   9  */
  10 
  11 /* include hwloc's config before anything else
  12  * so that extensions and features are properly enabled
  13  */
  14 #include <private/private.h>
  15 
  16 /*      $OpenBSD: base64.c,v 1.5 2006/10/21 09:55:03 otto Exp $ */
  17 
  18 /*
  19  * Copyright (c) 1996 by Internet Software Consortium.
  20  *
  21  * Permission to use, copy, modify, and distribute this software for any
  22  * purpose with or without fee is hereby granted, provided that the above
  23  * copyright notice and this permission notice appear in all copies.
  24  *
  25  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
  26  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  27  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  28  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  29  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  30  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  31  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  32  * SOFTWARE.
  33  */
  34 
  35 /*
  36  * Portions Copyright (c) 1995 by International Business Machines, Inc.
  37  *
  38  * International Business Machines, Inc. (hereinafter called IBM) grants
  39  * permission under its copyrights to use, copy, modify, and distribute this
  40  * Software with or without fee, provided that the above copyright notice and
  41  * all paragraphs of this notice appear in all copies, and that the name of IBM
  42  * not be used in connection with the marketing of any product incorporating
  43  * the Software or modifications thereof, without specific, written prior
  44  * permission.
  45  *
  46  * To the extent it has a right to do so, IBM grants an immunity from suit
  47  * under its patents, if any, for the use, sale or manufacture of products to
  48  * the extent that such products are used for performing Domain Name System
  49  * dynamic updates in TCP/IP networks by means of the Software.  No immunity is
  50  * granted for any product per se or for any other function of any product.
  51  *
  52  * THE SOFTWARE IS PROVIDED "AS IS", AND IBM DISCLAIMS ALL WARRANTIES,
  53  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
  54  * PARTICULAR PURPOSE.  IN NO EVENT SHALL IBM BE LIABLE FOR ANY SPECIAL,
  55  * DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER ARISING
  56  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE, EVEN
  57  * IF IBM IS APPRISED OF THE POSSIBILITY OF SUCH DAMAGES.
  58  */
  59 
  60 /* OPENBSD ORIGINAL: lib/libc/net/base64.c */
  61 
  62 static const char Base64[] =
  63         "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  64 static const char Pad64 = '=';
  65 
  66 /* (From RFC1521 and draft-ietf-dnssec-secext-03.txt)
  67    The following encoding technique is taken from RFC 1521 by Borenstein
  68    and Freed.  It is reproduced here in a slightly edited form for
  69    convenience.
  70 
  71    A 65-character subset of US-ASCII is used, enabling 6 bits to be
  72    represented per printable character. (The extra 65th character, "=",
  73    is used to signify a special processing function.)
  74 
  75    The encoding process represents 24-bit groups of input bits as output
  76    strings of 4 encoded characters. Proceeding from left to right, a
  77    24-bit input group is formed by concatenating 3 8-bit input groups.
  78    These 24 bits are then treated as 4 concatenated 6-bit groups, each
  79    of which is translated into a single digit in the base64 alphabet.
  80 
  81    Each 6-bit group is used as an index into an array of 64 printable
  82    characters. The character referenced by the index is placed in the
  83    output string.
  84 
  85                          Table 1: The Base64 Alphabet
  86 
  87       Value Encoding  Value Encoding  Value Encoding  Value Encoding
  88           0 A            17 R            34 i            51 z
  89           1 B            18 S            35 j            52 0
  90           2 C            19 T            36 k            53 1
  91           3 D            20 U            37 l            54 2
  92           4 E            21 V            38 m            55 3
  93           5 F            22 W            39 n            56 4
  94           6 G            23 X            40 o            57 5
  95           7 H            24 Y            41 p            58 6
  96           8 I            25 Z            42 q            59 7
  97           9 J            26 a            43 r            60 8
  98          10 K            27 b            44 s            61 9
  99          11 L            28 c            45 t            62 +
 100          12 M            29 d            46 u            63 /
 101          13 N            30 e            47 v
 102          14 O            31 f            48 w         (pad) =
 103          15 P            32 g            49 x
 104          16 Q            33 h            50 y
 105 
 106    Special processing is performed if fewer than 24 bits are available
 107    at the end of the data being encoded.  A full encoding quantum is
 108    always completed at the end of a quantity.  When fewer than 24 input
 109    bits are available in an input group, zero bits are added (on the
 110    right) to form an integral number of 6-bit groups.  Padding at the
 111    end of the data is performed using the '=' character.
 112 
 113    Since all base64 input is an integral number of octets, only the
 114          -------------------------------------------------
 115    following cases can arise:
 116 
 117        (1) the final quantum of encoding input is an integral
 118            multiple of 24 bits; here, the final unit of encoded
 119            output will be an integral multiple of 4 characters
 120            with no "=" padding,
 121        (2) the final quantum of encoding input is exactly 8 bits;
 122            here, the final unit of encoded output will be two
 123            characters followed by two "=" padding characters, or
 124        (3) the final quantum of encoding input is exactly 16 bits;
 125            here, the final unit of encoded output will be three
 126            characters followed by one "=" padding character.
 127    */
 128 
 129 #include <stdlib.h>
 130 #include <string.h>
 131 #include <ctype.h>
 132 
 133 int
 134 hwloc_encode_to_base64(const char *src, size_t srclength, char *target, size_t targsize)
 135 {
 136         size_t datalength = 0;
 137         unsigned char input[3];
 138         unsigned char output[4];
 139         unsigned int i;
 140 
 141         while (2 < srclength) {
 142                 input[0] = *src++;
 143                 input[1] = *src++;
 144                 input[2] = *src++;
 145                 srclength -= 3;
 146 
 147                 output[0] = input[0] >> 2;
 148                 output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4);
 149                 output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6);
 150                 output[3] = input[2] & 0x3f;
 151 
 152                 if (datalength + 4 > targsize)
 153                         return (-1);
 154                 target[datalength++] = Base64[output[0]];
 155                 target[datalength++] = Base64[output[1]];
 156                 target[datalength++] = Base64[output[2]];
 157                 target[datalength++] = Base64[output[3]];
 158         }
 159 
 160         /* Now we worry about padding. */
 161         if (0 != srclength) {
 162                 /* Get what's left. */
 163                 input[0] = input[1] = input[2] = '\0';
 164                 for (i = 0; i < srclength; i++)
 165                         input[i] = *src++;
 166 
 167                 output[0] = input[0] >> 2;
 168                 output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4);
 169                 output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6);
 170 
 171                 if (datalength + 4 > targsize)
 172                         return (-1);
 173                 target[datalength++] = Base64[output[0]];
 174                 target[datalength++] = Base64[output[1]];
 175                 if (srclength == 1)
 176                         target[datalength++] = Pad64;
 177                 else
 178                         target[datalength++] = Base64[output[2]];
 179                 target[datalength++] = Pad64;
 180         }
 181         if (datalength >= targsize)
 182                 return (-1);
 183         target[datalength] = '\0';      /* Returned value doesn't count \0. */
 184         return (int)(datalength);
 185 }
 186 
 187 /* skips all whitespace anywhere.
 188    converts characters, four at a time, starting at (or after)
 189    src from base - 64 numbers into three 8 bit bytes in the target area.
 190    it returns the number of data bytes stored at the target, or -1 on error.
 191  */
 192 
 193 int
 194 hwloc_decode_from_base64(char const *src, char *target, size_t targsize)
 195 {
 196         unsigned int tarindex, state;
 197         int ch;
 198         char *pos;
 199 
 200         state = 0;
 201         tarindex = 0;
 202 
 203         while ((ch = *src++) != '\0') {
 204                 if (isspace(ch))        /* Skip whitespace anywhere. */
 205                         continue;
 206 
 207                 if (ch == Pad64)
 208                         break;
 209 
 210                 pos = strchr(Base64, ch);
 211                 if (pos == 0)           /* A non-base64 character. */
 212                         return (-1);
 213 
 214                 switch (state) {
 215                 case 0:
 216                         if (target) {
 217                                 if (tarindex >= targsize)
 218                                         return (-1);
 219                                 target[tarindex] = (char)(pos - Base64) << 2;
 220                         }
 221                         state = 1;
 222                         break;
 223                 case 1:
 224                         if (target) {
 225                                 if (tarindex + 1 >= targsize)
 226                                         return (-1);
 227                                 target[tarindex]   |=  (pos - Base64) >> 4;
 228                                 target[tarindex+1]  = ((pos - Base64) & 0x0f)
 229                                                         << 4 ;
 230                         }
 231                         tarindex++;
 232                         state = 2;
 233                         break;
 234                 case 2:
 235                         if (target) {
 236                                 if (tarindex + 1 >= targsize)
 237                                         return (-1);
 238                                 target[tarindex]   |=  (pos - Base64) >> 2;
 239                                 target[tarindex+1]  = ((pos - Base64) & 0x03)
 240                                                         << 6;
 241                         }
 242                         tarindex++;
 243                         state = 3;
 244                         break;
 245                 case 3:
 246                         if (target) {
 247                                 if (tarindex >= targsize)
 248                                         return (-1);
 249                                 target[tarindex] |= (pos - Base64);
 250                         }
 251                         tarindex++;
 252                         state = 0;
 253                         break;
 254                 }
 255         }
 256 
 257         /*
 258          * We are done decoding Base-64 chars.  Let's see if we ended
 259          * on a byte boundary, and/or with erroneous trailing characters.
 260          */
 261 
 262         if (ch == Pad64) {              /* We got a pad char. */
 263                 ch = *src++;            /* Skip it, get next. */
 264                 switch (state) {
 265                 case 0:         /* Invalid = in first position */
 266                 case 1:         /* Invalid = in second position */
 267                         return (-1);
 268 
 269                 case 2:         /* Valid, means one byte of info */
 270                         /* Skip any number of spaces. */
 271                         for (; ch != '\0'; ch = *src++)
 272                                 if (!isspace(ch))
 273                                         break;
 274                         /* Make sure there is another trailing = sign. */
 275                         if (ch != Pad64)
 276                                 return (-1);
 277                         ch = *src++;            /* Skip the = */
 278                         /* Fall through to "single trailing =" case. */
 279                         /* FALLTHROUGH */
 280 
 281                 case 3:         /* Valid, means two bytes of info */
 282                         /*
 283                          * We know this char is an =.  Is there anything but
 284                          * whitespace after it?
 285                          */
 286                         for (; ch != '\0'; ch = *src++)
 287                                 if (!isspace(ch))
 288                                         return (-1);
 289 
 290                         /*
 291                          * Now make sure for cases 2 and 3 that the "extra"
 292                          * bits that slopped past the last full byte were
 293                          * zeros.  If we don't check them, they become a
 294                          * subliminal channel.
 295                          */
 296                         if (target && target[tarindex] != 0)
 297                                 return (-1);
 298                 }
 299         } else {
 300                 /*
 301                  * We ended by seeing the end of the string.  Make sure we
 302                  * have no partial bytes lying around.
 303                  */
 304                 if (state != 0)
 305                         return (-1);
 306         }
 307 
 308         return (tarindex);
 309 }

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