1 /* $OpenBSD: encode.c,v 1.23 2016/05/04 14:53:29 tedu Exp $ */ 2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59 #include <limits.h> 60 #include <stdio.h> 61 #include <string.h> 62 63 #include <openssl/evp.h> 64 65 #define conv_bin2ascii(a) (data_bin2ascii[(a)&0x3f]) 66 #define conv_ascii2bin(a) (data_ascii2bin[(a)&0x7f]) 67 68 /* 64 char lines 69 * pad input with 0 70 * left over chars are set to = 71 * 1 byte => xx== 72 * 2 bytes => xxx= 73 * 3 bytes => xxxx 74 */ 75 #define BIN_PER_LINE (64/4*3) 76 #define CHUNKS_PER_LINE (64/4) 77 #define CHAR_PER_LINE (64+1) 78 79 static const unsigned char data_bin2ascii[65] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ\ 80 abcdefghijklmnopqrstuvwxyz0123456789+/"; 81 82 /* 0xF0 is a EOLN 83 * 0xF1 is ignore but next needs to be 0xF0 (for \r\n processing). 84 * 0xF2 is EOF 85 * 0xE0 is ignore at start of line. 86 * 0xFF is error 87 */ 88 89 #define B64_EOLN 0xF0 90 #define B64_CR 0xF1 91 #define B64_EOF 0xF2 92 #define B64_WS 0xE0 93 #define B64_ERROR 0xFF 94 #define B64_NOT_BASE64(a) (((a)|0x13) == 0xF3) 95 96 static const unsigned char data_ascii2bin[128] = { 97 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 98 0xFF, 0xE0, 0xF0, 0xFF, 0xFF, 0xF1, 0xFF, 0xFF, 99 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 100 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 101 0xE0, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 102 0xFF, 0xFF, 0xFF, 0x3E, 0xFF, 0xF2, 0xFF, 0x3F, 103 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 104 0x3C, 0x3D, 0xFF, 0xFF, 0xFF, 0x00, 0xFF, 0xFF, 105 0xFF, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 106 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 107 0x0F, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 108 0x17, 0x18, 0x19, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 109 0xFF, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 110 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 111 0x29, 0x2A, 0x2B, 0x2C, 0x2D, 0x2E, 0x2F, 0x30, 112 0x31, 0x32, 0x33, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 113 }; 114 115 void 116 EVP_EncodeInit(EVP_ENCODE_CTX *ctx) 117 { 118 ctx->length = 48; 119 ctx->num = 0; 120 ctx->line_num = 0; 121 } 122 123 void 124 EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl, 125 const unsigned char *in, int inl) 126 { 127 int i, j; 128 size_t total = 0; 129 130 *outl = 0; 131 if (inl == 0) 132 return; 133 OPENSSL_assert(ctx->length <= (int)sizeof(ctx->enc_data)); 134 if (ctx->length - ctx->num > inl) { 135 memcpy(&(ctx->enc_data[ctx->num]), in, inl); 136 ctx->num += inl; 137 return; 138 } 139 if (ctx->num != 0) { 140 i = ctx->length - ctx->num; 141 memcpy(&(ctx->enc_data[ctx->num]), in, i); 142 in += i; 143 inl -= i; 144 j = EVP_EncodeBlock(out, ctx->enc_data, ctx->length); 145 ctx->num = 0; 146 out += j; 147 *(out++) = '\n'; 148 *out = '\0'; 149 total = j + 1; 150 } 151 while (inl >= ctx->length && total <= INT_MAX) { 152 j = EVP_EncodeBlock(out, in, ctx->length); 153 in += ctx->length; 154 inl -= ctx->length; 155 out += j; 156 *(out++) = '\n'; 157 *out = '\0'; 158 total += j + 1; 159 } 160 if (total > INT_MAX) { 161 /* Too much output data! */ 162 *outl = 0; 163 return; 164 } 165 if (inl != 0) 166 memcpy(&(ctx->enc_data[0]), in, inl); 167 ctx->num = inl; 168 *outl = total; 169 } 170 171 void 172 EVP_EncodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl) 173 { 174 unsigned int ret = 0; 175 176 if (ctx->num != 0) { 177 ret = EVP_EncodeBlock(out, ctx->enc_data, ctx->num); 178 out[ret++] = '\n'; 179 out[ret] = '\0'; 180 ctx->num = 0; 181 } 182 *outl = ret; 183 } 184 185 int 186 EVP_EncodeBlock(unsigned char *t, const unsigned char *f, int dlen) 187 { 188 int i, ret = 0; 189 unsigned long l; 190 191 for (i = dlen; i > 0; i -= 3) { 192 if (i >= 3) { 193 l = (((unsigned long)f[0]) << 16L) | 194 (((unsigned long)f[1]) << 8L) | f[2]; 195 *(t++) = conv_bin2ascii(l >> 18L); 196 *(t++) = conv_bin2ascii(l >> 12L); 197 *(t++) = conv_bin2ascii(l >> 6L); 198 *(t++) = conv_bin2ascii(l ); 199 } else { 200 l = ((unsigned long)f[0]) << 16L; 201 if (i == 2) 202 l |= ((unsigned long)f[1] << 8L); 203 204 *(t++) = conv_bin2ascii(l >> 18L); 205 *(t++) = conv_bin2ascii(l >> 12L); 206 *(t++) = (i == 1) ? '=' : conv_bin2ascii(l >> 6L); 207 *(t++) = '='; 208 } 209 ret += 4; 210 f += 3; 211 } 212 213 *t = '\0'; 214 return (ret); 215 } 216 217 void 218 EVP_DecodeInit(EVP_ENCODE_CTX *ctx) 219 { 220 ctx->length = 30; 221 ctx->num = 0; 222 ctx->line_num = 0; 223 ctx->expect_nl = 0; 224 } 225 226 /* -1 for error 227 * 0 for last line 228 * 1 for full line 229 */ 230 int 231 EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl, 232 const unsigned char *in, int inl) 233 { 234 int seof = -1, eof = 0, rv = -1, ret = 0, i, v, tmp, n, ln, exp_nl; 235 unsigned char *d; 236 237 n = ctx->num; 238 d = ctx->enc_data; 239 ln = ctx->line_num; 240 exp_nl = ctx->expect_nl; 241 242 /* last line of input. */ 243 if ((inl == 0) || ((n == 0) && (conv_ascii2bin(in[0]) == B64_EOF))) { 244 rv = 0; 245 goto end; 246 } 247 248 /* We parse the input data */ 249 for (i = 0; i < inl; i++) { 250 /* If the current line is > 80 characters, scream alot */ 251 if (ln >= 80) { 252 rv = -1; 253 goto end; 254 } 255 256 /* Get char and put it into the buffer */ 257 tmp= *(in++); 258 v = conv_ascii2bin(tmp); 259 /* only save the good data :-) */ 260 if (!B64_NOT_BASE64(v)) { 261 OPENSSL_assert(n < (int)sizeof(ctx->enc_data)); 262 d[n++] = tmp; 263 ln++; 264 } else if (v == B64_ERROR) { 265 rv = -1; 266 goto end; 267 } 268 269 /* There should not be base64 data after padding. */ 270 if (eof && tmp != '=' && tmp != '\r' && tmp != '\n' && 271 v != B64_EOF) { 272 rv = -1; 273 goto end; 274 } 275 276 /* have we seen a '=' which is 'definitely' the last 277 * input line. seof will point to the character that 278 * holds it. and eof will hold how many characters to 279 * chop off. */ 280 if (tmp == '=') { 281 if (seof == -1) 282 seof = n; 283 eof++; 284 } 285 286 /* There should be no more than two padding markers. */ 287 if (eof > 2) { 288 rv = -1; 289 goto end; 290 } 291 292 if (v == B64_CR) { 293 ln = 0; 294 if (exp_nl) 295 continue; 296 } 297 298 /* eoln */ 299 if (v == B64_EOLN) { 300 ln = 0; 301 if (exp_nl) { 302 exp_nl = 0; 303 continue; 304 } 305 } 306 exp_nl = 0; 307 308 /* If we are at the end of input and it looks like a 309 * line, process it. */ 310 if (((i + 1) == inl) && (((n&3) == 0) || eof)) { 311 v = B64_EOF; 312 /* In case things were given us in really small 313 records (so two '=' were given in separate 314 updates), eof may contain the incorrect number 315 of ending bytes to skip, so let's redo the count */ 316 eof = 0; 317 if (d[n-1] == '=') 318 eof++; 319 if (d[n-2] == '=') 320 eof++; 321 /* There will never be more than two '=' */ 322 } 323 324 if ((v == B64_EOF && (n&3) == 0) || (n >= 64)) { 325 /* This is needed to work correctly on 64 byte input 326 * lines. We process the line and then need to 327 * accept the '\n' */ 328 if ((v != B64_EOF) && (n >= 64)) 329 exp_nl = 1; 330 if (n > 0) { 331 v = EVP_DecodeBlock(out, d, n); 332 n = 0; 333 if (v < 0) { 334 rv = 0; 335 goto end; 336 } 337 ret += (v - eof); 338 } else { 339 eof = 1; 340 v = 0; 341 } 342 343 /* This is the case where we have had a short 344 * but valid input line */ 345 if ((v < ctx->length) && eof) { 346 rv = 0; 347 goto end; 348 } else 349 ctx->length = v; 350 351 if (seof >= 0) { 352 rv = 0; 353 goto end; 354 } 355 out += v; 356 } 357 } 358 rv = 1; 359 360 end: 361 *outl = ret; 362 ctx->num = n; 363 ctx->line_num = ln; 364 ctx->expect_nl = exp_nl; 365 return (rv); 366 } 367 368 int 369 EVP_DecodeBlock(unsigned char *t, const unsigned char *f, int n) 370 { 371 int i, ret = 0, a, b, c, d; 372 unsigned long l; 373 374 /* trim white space from the start of the line. */ 375 while ((conv_ascii2bin(*f) == B64_WS) && (n > 0)) { 376 f++; 377 n--; 378 } 379 380 /* strip off stuff at the end of the line 381 * ascii2bin values B64_WS, B64_EOLN, B64_EOLN and B64_EOF */ 382 while ((n > 3) && (B64_NOT_BASE64(conv_ascii2bin(f[n - 1])))) 383 n--; 384 385 if (n % 4 != 0) 386 return (-1); 387 388 for (i = 0; i < n; i += 4) { 389 a = conv_ascii2bin(*(f++)); 390 b = conv_ascii2bin(*(f++)); 391 c = conv_ascii2bin(*(f++)); 392 d = conv_ascii2bin(*(f++)); 393 if ((a & 0x80) || (b & 0x80) || 394 (c & 0x80) || (d & 0x80)) 395 return (-1); 396 l = ((((unsigned long)a) << 18L) | 397 (((unsigned long)b) << 12L) | 398 (((unsigned long)c) << 6L) | 399 (((unsigned long)d))); 400 *(t++) = (unsigned char)(l >> 16L) & 0xff; 401 *(t++) = (unsigned char)(l >> 8L) & 0xff; 402 *(t++) = (unsigned char)(l) & 0xff; 403 ret += 3; 404 } 405 return (ret); 406 } 407 408 int 409 EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl) 410 { 411 int i; 412 413 *outl = 0; 414 if (ctx->num != 0) { 415 i = EVP_DecodeBlock(out, ctx->enc_data, ctx->num); 416 if (i < 0) 417 return (-1); 418 ctx->num = 0; 419 *outl = i; 420 return (1); 421 } else 422 return (1); 423 } 424