1 /* 2 * Copyright 2009 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 4 */ 5 6 7 /* 8 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 9 * Copyright (c) 1996-1999 by Internet Software Consortium. 10 * 11 * Permission to use, copy, modify, and distribute this software for any 12 * purpose with or without fee is hereby granted, provided that the above 13 * copyright notice and this permission notice appear in all copies. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 16 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 17 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 18 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 19 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 20 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 21 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 22 */ 23 24 /* 25 * Portions Copyright (c) 1995 by International Business Machines, Inc. 26 * 27 * International Business Machines, Inc. (hereinafter called IBM) grants 28 * permission under its copyrights to use, copy, modify, and distribute this 29 * Software with or without fee, provided that the above copyright notice and 30 * all paragraphs of this notice appear in all copies, and that the name of IBM 31 * not be used in connection with the marketing of any product incorporating 32 * the Software or modifications thereof, without specific, written prior 33 * permission. 34 * 35 * To the extent it has a right to do so, IBM grants an immunity from suit 36 * under its patents, if any, for the use, sale or manufacture of products to 37 * the extent that such products are used for performing Domain Name System 38 * dynamic updates in TCP/IP networks by means of the Software. No immunity is 39 * granted for any product per se or for any other function of any product. 40 * 41 * THE SOFTWARE IS PROVIDED "AS IS", AND IBM DISCLAIMS ALL WARRANTIES, 42 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 43 * PARTICULAR PURPOSE. IN NO EVENT SHALL IBM BE LIABLE FOR ANY SPECIAL, 44 * DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER ARISING 45 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE, EVEN 46 * IF IBM IS APPRISED OF THE POSSIBILITY OF SUCH DAMAGES. 47 */ 48 49 #include "port_before.h" 50 51 #include <sys/types.h> 52 #include <sys/param.h> 53 #include <sys/socket.h> 54 55 #include <netinet/in.h> 56 #include <arpa/inet.h> 57 #include <arpa/nameser.h> 58 59 #include <ctype.h> 60 #include <resolv.h> 61 #include <stdio.h> 62 #include <stdlib.h> 63 #include <string.h> 64 65 #include "port_after.h" 66 67 #ifndef ORIGINAL_ISC_CODE 68 #pragma weak __b64_ntop = b64_ntop 69 #pragma weak __b64_pton = b64_pton 70 #endif /* ORIGINAL_ISC_CODE */ 71 72 #define Assert(Cond) if (!(Cond)) abort() 73 74 static const char Base64[] = 75 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; 76 static const char Pad64 = '='; 77 78 /* (From RFC1521 and draft-ietf-dnssec-secext-03.txt) 79 The following encoding technique is taken from RFC1521 by Borenstein 80 and Freed. It is reproduced here in a slightly edited form for 81 convenience. 82 83 A 65-character subset of US-ASCII is used, enabling 6 bits to be 84 represented per printable character. (The extra 65th character, "=", 85 is used to signify a special processing function.) 86 87 The encoding process represents 24-bit groups of input bits as output 88 strings of 4 encoded characters. Proceeding from left to right, a 89 24-bit input group is formed by concatenating 3 8-bit input groups. 90 These 24 bits are then treated as 4 concatenated 6-bit groups, each 91 of which is translated into a single digit in the base64 alphabet. 92 93 Each 6-bit group is used as an index into an array of 64 printable 94 characters. The character referenced by the index is placed in the 95 output string. 96 97 Table 1: The Base64 Alphabet 98 99 Value Encoding Value Encoding Value Encoding Value Encoding 100 0 A 17 R 34 i 51 z 101 1 B 18 S 35 j 52 0 102 2 C 19 T 36 k 53 1 103 3 D 20 U 37 l 54 2 104 4 E 21 V 38 m 55 3 105 5 F 22 W 39 n 56 4 106 6 G 23 X 40 o 57 5 107 7 H 24 Y 41 p 58 6 108 8 I 25 Z 42 q 59 7 109 9 J 26 a 43 r 60 8 110 10 K 27 b 44 s 61 9 111 11 L 28 c 45 t 62 + 112 12 M 29 d 46 u 63 / 113 13 N 30 e 47 v 114 14 O 31 f 48 w (pad) = 115 15 P 32 g 49 x 116 16 Q 33 h 50 y 117 118 Special processing is performed if fewer than 24 bits are available 119 at the end of the data being encoded. A full encoding quantum is 120 always completed at the end of a quantity. When fewer than 24 input 121 bits are available in an input group, zero bits are added (on the 122 right) to form an integral number of 6-bit groups. Padding at the 123 end of the data is performed using the '=' character. 124 125 Since all base64 input is an integral number of octets, only the 126 ------------------------------------------------- 127 following cases can arise: 128 129 (1) the final quantum of encoding input is an integral 130 multiple of 24 bits; here, the final unit of encoded 131 output will be an integral multiple of 4 characters 132 with no "=" padding, 133 (2) the final quantum of encoding input is exactly 8 bits; 134 here, the final unit of encoded output will be two 135 characters followed by two "=" padding characters, or 136 (3) the final quantum of encoding input is exactly 16 bits; 137 here, the final unit of encoded output will be three 138 characters followed by one "=" padding character. 139 */ 140 141 int 142 b64_ntop(u_char const *src, size_t srclength, char *target, size_t targsize) { 143 size_t datalength = 0; 144 u_char input[3]; 145 u_char output[4]; 146 size_t i; 147 148 while (2U < srclength) { 149 input[0] = *src++; 150 input[1] = *src++; 151 input[2] = *src++; 152 srclength -= 3; 153 154 output[0] = input[0] >> 2; 155 output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4); 156 output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6); 157 output[3] = input[2] & 0x3f; 158 Assert(output[0] < 64); 159 Assert(output[1] < 64); 160 Assert(output[2] < 64); 161 Assert(output[3] < 64); 162 163 if (datalength + 4 > targsize) 164 return (-1); 165 target[datalength++] = Base64[output[0]]; 166 target[datalength++] = Base64[output[1]]; 167 target[datalength++] = Base64[output[2]]; 168 target[datalength++] = Base64[output[3]]; 169 } 170 171 /* Now we worry about padding. */ 172 if (0U != srclength) { 173 /* Get what's left. */ 174 input[0] = input[1] = input[2] = '\0'; 175 for (i = 0; i < srclength; i++) 176 input[i] = *src++; 177 178 output[0] = input[0] >> 2; 179 output[1] = ((input[0] & 0x03) << 4) + (input[1] >> 4); 180 output[2] = ((input[1] & 0x0f) << 2) + (input[2] >> 6); 181 Assert(output[0] < 64); 182 Assert(output[1] < 64); 183 Assert(output[2] < 64); 184 185 if (datalength + 4 > targsize) 186 return (-1); 187 target[datalength++] = Base64[output[0]]; 188 target[datalength++] = Base64[output[1]]; 189 if (srclength == 1U) 190 target[datalength++] = Pad64; 191 else 192 target[datalength++] = Base64[output[2]]; 193 target[datalength++] = Pad64; 194 } 195 if (datalength >= targsize) 196 return (-1); 197 target[datalength] = '\0'; /*%< Returned value doesn't count \\0. */ 198 return (datalength); 199 } 200 201 /* skips all whitespace anywhere. 202 converts characters, four at a time, starting at (or after) 203 src from base - 64 numbers into three 8 bit bytes in the target area. 204 it returns the number of data bytes stored at the target, or -1 on error. 205 */ 206 207 int 208 b64_pton(src, target, targsize) 209 char const *src; 210 u_char *target; 211 size_t targsize; 212 { 213 int tarindex, state, ch; 214 char *pos; 215 216 state = 0; 217 tarindex = 0; 218 219 while ((ch = *src++) != '\0') { 220 if (isspace(ch)) /*%< Skip whitespace anywhere. */ 221 continue; 222 223 if (ch == Pad64) 224 break; 225 226 pos = strchr(Base64, ch); 227 if (pos == 0) /*%< A non-base64 character. */ 228 return (-1); 229 230 switch (state) { 231 case 0: 232 if (target) { 233 if ((size_t)tarindex >= targsize) 234 return (-1); 235 target[tarindex] = (pos - Base64) << 2; 236 } 237 state = 1; 238 break; 239 case 1: 240 if (target) { 241 if ((size_t)tarindex + 1 >= targsize) 242 return (-1); 243 target[tarindex] |= (pos - Base64) >> 4; 244 target[tarindex+1] = ((pos - Base64) & 0x0f) 245 << 4 ; 246 } 247 tarindex++; 248 state = 2; 249 break; 250 case 2: 251 if (target) { 252 if ((size_t)tarindex + 1 >= targsize) 253 return (-1); 254 target[tarindex] |= (pos - Base64) >> 2; 255 target[tarindex+1] = ((pos - Base64) & 0x03) 256 << 6; 257 } 258 tarindex++; 259 state = 3; 260 break; 261 case 3: 262 if (target) { 263 if ((size_t)tarindex >= targsize) 264 return (-1); 265 target[tarindex] |= (pos - Base64); 266 } 267 tarindex++; 268 state = 0; 269 break; 270 default: 271 abort(); 272 } 273 } 274 275 /* 276 * We are done decoding Base-64 chars. Let's see if we ended 277 * on a byte boundary, and/or with erroneous trailing characters. 278 */ 279 280 if (ch == Pad64) { /*%< We got a pad char. */ 281 ch = *src++; /*%< Skip it, get next. */ 282 switch (state) { 283 case 0: /*%< Invalid = in first position */ 284 case 1: /*%< Invalid = in second position */ 285 return (-1); 286 287 case 2: /*%< Valid, means one byte of info */ 288 /* Skip any number of spaces. */ 289 for ((void)NULL; ch != '\0'; ch = *src++) 290 if (!isspace(ch)) 291 break; 292 /* Make sure there is another trailing = sign. */ 293 if (ch != Pad64) 294 return (-1); 295 ch = *src++; /*%< Skip the = */ 296 /* Fall through to "single trailing =" case. */ 297 /* FALLTHROUGH */ 298 299 case 3: /*%< Valid, means two bytes of info */ 300 /* 301 * We know this char is an =. Is there anything but 302 * whitespace after it? 303 */ 304 for ((void)NULL; ch != '\0'; ch = *src++) 305 if (!isspace(ch)) 306 return (-1); 307 308 /* 309 * Now make sure for cases 2 and 3 that the "extra" 310 * bits that slopped past the last full byte were 311 * zeros. If we don't check them, they become a 312 * subliminal channel. 313 */ 314 if (target && target[tarindex] != 0) 315 return (-1); 316 } 317 } else { 318 /* 319 * We ended by seeing the end of the string. Make sure we 320 * have no partial bytes lying around. 321 */ 322 if (state != 0) 323 return (-1); 324 } 325 326 return (tarindex); 327 } 328 329 /*! \file */ 330