1 /* 2 * Copyright (c) 1996, 1998 by Internet Software Consortium. 3 * 4 * Permission to use, copy, modify, and distribute this software for any 5 * purpose with or without fee is hereby granted, provided that the above 6 * copyright notice and this permission notice appear in all copies. 7 * 8 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS 9 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES 10 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE 11 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 12 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 13 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 14 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 15 * SOFTWARE. 16 */ 17 18 /* 19 * Portions Copyright (c) 1995 by International Business Machines, Inc. 20 * 21 * International Business Machines, Inc. (hereinafter called IBM) grants 22 * permission under its copyrights to use, copy, modify, and distribute this 23 * Software with or without fee, provided that the above copyright notice and 24 * all paragraphs of this notice appear in all copies, and that the name of IBM 25 * not be used in connection with the marketing of any product incorporating 26 * the Software or modifications thereof, without specific, written prior 27 * permission. 28 * 29 * To the extent it has a right to do so, IBM grants an immunity from suit 30 * under its patents, if any, for the use, sale or manufacture of products to 31 * the extent that such products are used for performing Domain Name System 32 * dynamic updates in TCP/IP networks by means of the Software. No immunity is 33 * granted for any product per se or for any other function of any product. 34 * 35 * THE SOFTWARE IS PROVIDED "AS IS", AND IBM DISCLAIMS ALL WARRANTIES, 36 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 37 * PARTICULAR PURPOSE. IN NO EVENT SHALL IBM BE LIABLE FOR ANY SPECIAL, 38 * DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER ARISING 39 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE, EVEN 40 * IF IBM IS APPRISED OF THE POSSIBILITY OF SUCH DAMAGES. 41 */ 42 43 /* 44 * Portions copyright (c) 1999, 2000 45 * Intel Corporation. 46 * All rights reserved. 47 * 48 * Redistribution and use in source and binary forms, with or without 49 * modification, are permitted provided that the following conditions 50 * are met: 51 * 52 * 1. Redistributions of source code must retain the above copyright 53 * notice, this list of conditions and the following disclaimer. 54 * 55 * 2. Redistributions in binary form must reproduce the above copyright 56 * notice, this list of conditions and the following disclaimer in the 57 * documentation and/or other materials provided with the distribution. 58 * 59 * 3. All advertising materials mentioning features or use of this software 60 * must display the following acknowledgement: 61 * 62 * This product includes software developed by Intel Corporation and 63 * its contributors. 64 * 65 * 4. Neither the name of Intel Corporation or its contributors may be 66 * used to endorse or promote products derived from this software 67 * without specific prior written permission. 68 * 69 * THIS SOFTWARE IS PROVIDED BY INTEL CORPORATION AND CONTRIBUTORS ``AS IS'' 70 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 71 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 72 * ARE DISCLAIMED. IN NO EVENT SHALL INTEL CORPORATION OR CONTRIBUTORS BE 73 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 74 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 75 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 76 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 77 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 78 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 79 * THE POSSIBILITY OF SUCH DAMAGE. 80 * 81 base64.c,v 1.1.1.1 2003/11/19 01:51:25 kyu3 Exp 82 */ 83 84 #include <sys/types.h> 85 #include <sys/param.h> 86 #include <sys/socket.h> 87 88 #include <netinet/in.h> 89 #include <arpa/inet.h> 90 #include <arpa/nameser.h> 91 92 #include <ctype.h> 93 #include <resolv.h> 94 #include <stdio.h> 95 #include <stdlib.h> 96 #include <string.h> 97 98 #define Assert(Cond) if (!(Cond)) abort() 99 100 static const char Base64[] = 101 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; 102 static const char Pad64 = '='; 103 104 /* (From RFC1521 and draft-ietf-dnssec-secext-03.txt) 105 The following encoding technique is taken from RFC 1521 by Borenstein 106 and Freed. It is reproduced here in a slightly edited form for 107 convenience. 108 109 A 65-character subset of US-ASCII is used, enabling 6 bits to be 110 represented per printable character. (The extra 65th character, "=", 111 is used to signify a special processing function.) 112 113 The encoding process represents 24-bit groups of input bits as output 114 strings of 4 encoded characters. Proceeding from left to right, a 115 24-bit input group is formed by concatenating 3 8-bit input groups. 116 These 24 bits are then treated as 4 concatenated 6-bit groups, each 117 of which is translated into a single digit in the base64 alphabet. 118 119 Each 6-bit group is used as an index into an array of 64 printable 120 characters. The character referenced by the index is placed in the 121 output string. 122 123 Table 1: The Base64 Alphabet 124 125 Value Encoding Value Encoding Value Encoding Value Encoding 126 0 A 17 R 34 i 51 z 127 1 B 18 S 35 j 52 0 128 2 C 19 T 36 k 53 1 129 3 D 20 U 37 l 54 2 130 4 E 21 V 38 m 55 3 131 5 F 22 W 39 n 56 4 132 6 G 23 X 40 o 57 5 133 7 H 24 Y 41 p 58 6 134 8 I 25 Z 42 q 59 7 135 9 J 26 a 43 r 60 8 136 10 K 27 b 44 s 61 9 137 11 L 28 c 45 t 62 + 138 12 M 29 d 46 u 63 / 139 13 N 30 e 47 v 140 14 O 31 f 48 w (pad) = 141 15 P 32 g 49 x 142 16 Q 33 h 50 y 143 144 Special processing is performed if fewer than 24 bits are available 145 at the end of the data being encoded. A full encoding quantum is 146 always completed at the end of a quantity. When fewer than 24 input 147 bits are available in an input group, zero bits are added (on the 148 right) to form an integral number of 6-bit groups. Padding at the 149 end of the data is performed using the '=' character. 150 151 Since all base64 input is an integral number of octets, only the 152 ------------------------------------------------- 153 following cases can arise: 154 155 (1) the final quantum of encoding input is an integral 156 multiple of 24 bits; here, the final unit of encoded 157 output will be an integral multiple of 4 characters 158 with no "=" padding, 159 (2) the final quantum of encoding input is exactly 8 bits; 160 here, the final unit of encoded output will be two 161 characters followed by two "=" padding characters, or 162 (3) the final quantum of encoding input is exactly 16 bits; 163 here, the final unit of encoded output will be three 164 characters followed by one "=" padding character. 165 */ 166 167 int 168 b64_ntop(u_char const *src, size_t srclength, char *target, size_t targsize) { 169 size_t datalength = 0; 170 u_char input[3]; 171 u_char output[4]; 172 size_t i; 173 174 input[0] = input[1] = input[2] = '\0'; 175 while (2 < srclength) { 176 input[0] = *src++; 177 input[1] = *src++; 178 input[2] = *src++; 179 srclength -= 3; 180 181 output[0] = input[0] >> 2; 182 output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4); 183 output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6); 184 output[3] = input[2] & 0x3f; 185 Assert(output[0] < 64); 186 Assert(output[1] < 64); 187 Assert(output[2] < 64); 188 Assert(output[3] < 64); 189 190 if (datalength + 4 > targsize) 191 return (-1); 192 target[datalength++] = Base64[output[0]]; 193 target[datalength++] = Base64[output[1]]; 194 target[datalength++] = Base64[output[2]]; 195 target[datalength++] = Base64[output[3]]; 196 } 197 198 /* Now we worry about padding. */ 199 if (0 != srclength) { 200 /* Get what's left. */ 201 input[0] = input[1] = input[2] = '\0'; 202 for (i = 0; i < srclength; i++) 203 input[i] = *src++; 204 205 output[0] = input[0] >> 2; 206 output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4); 207 output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6); 208 Assert(output[0] < 64); 209 Assert(output[1] < 64); 210 Assert(output[2] < 64); 211 212 if (datalength + 4 > targsize) 213 return (-1); 214 target[datalength++] = Base64[output[0]]; 215 target[datalength++] = Base64[output[1]]; 216 if (srclength == 1) 217 target[datalength++] = Pad64; 218 else 219 target[datalength++] = Base64[output[2]]; 220 target[datalength++] = Pad64; 221 } 222 if (datalength >= targsize) 223 return (-1); 224 target[datalength] = '\0'; /* Returned value doesn't count \0. */ 225 return ((int)datalength); 226 } 227 228 /* skips all whitespace anywhere. 229 converts characters, four at a time, starting at (or after) 230 src from base - 64 numbers into three 8 bit bytes in the target area. 231 it returns the number of data bytes stored at the target, or -1 on error. 232 */ 233 234 int 235 b64_pton( 236 char const *src, 237 u_char *target, 238 size_t targsize 239 ) 240 { 241 int tarindex, state, ch; 242 char *pos; 243 244 state = 0; 245 tarindex = 0; 246 247 while ((ch = *src++) != '\0') { 248 if (isspace(ch)) /* Skip whitespace anywhere. */ 249 continue; 250 251 if (ch == Pad64) 252 break; 253 254 pos = strchr(Base64, ch); 255 if (pos == 0) /* A non-base64 character. */ 256 return (-1); 257 258 switch (state) { 259 case 0: 260 if (target) { 261 if ((size_t)tarindex >= targsize) 262 return (-1); 263 target[tarindex] = (u_char)((pos - Base64) << 2); 264 } 265 state = 1; 266 break; 267 case 1: 268 if (target) { 269 if ((size_t)tarindex + 1 >= targsize) 270 return (-1); 271 target[tarindex] |= (u_char)((pos - Base64) >> 4); 272 target[tarindex+1] = (u_char)(((pos - Base64) & 0x0f) 273 << 4) ; 274 } 275 tarindex++; 276 state = 2; 277 break; 278 case 2: 279 if (target) { 280 if ((size_t)tarindex + 1 >= targsize) 281 return (-1); 282 target[tarindex] |= (u_char)((pos - Base64) >> 2); 283 target[tarindex+1] = (u_char)(((pos - Base64) & 0x03) 284 << 6); 285 } 286 tarindex++; 287 state = 3; 288 break; 289 case 3: 290 if (target) { 291 if ((size_t)tarindex >= targsize) 292 return (-1); 293 target[tarindex] |= (u_char)(pos - Base64); 294 } 295 tarindex++; 296 state = 0; 297 break; 298 default: 299 abort(); 300 } 301 } 302 303 /* 304 * We are done decoding Base-64 chars. Let's see if we ended 305 * on a byte boundary, and/or with erroneous trailing characters. 306 */ 307 308 if (ch == Pad64) { /* We got a pad char. */ 309 ch = *src++; /* Skip it, get next. */ 310 switch (state) { 311 case 0: /* Invalid = in first position */ 312 case 1: /* Invalid = in second position */ 313 return (-1); 314 315 case 2: /* Valid, means one byte of info */ 316 /* Skip any number of spaces. */ 317 for ((void)NULL; ch != '\0'; ch = *src++) 318 if (!isspace(ch)) 319 break; 320 /* Make sure there is another trailing = sign. */ 321 if (ch != Pad64) 322 return (-1); 323 ch = *src++; /* Skip the = */ 324 /* Fall through to "single trailing =" case. */ 325 /* FALLTHROUGH */ 326 327 case 3: /* Valid, means two bytes of info */ 328 /* 329 * We know this char is an =. Is there anything but 330 * whitespace after it? 331 */ 332 for ((void)NULL; ch != '\0'; ch = *src++) 333 if (!isspace(ch)) 334 return (-1); 335 336 /* 337 * Now make sure for cases 2 and 3 that the "extra" 338 * bits that slopped past the last full byte were 339 * zeros. If we don't check them, they become a 340 * subliminal channel. 341 */ 342 if (target && target[tarindex] != 0) 343 return (-1); 344 } 345 } else { 346 /* 347 * We ended by seeing the end of the string. Make sure we 348 * have no partial bytes lying around. 349 */ 350 if (state != 0) 351 return (-1); 352 } 353 354 return (tarindex); 355 } 356
