1/* 2 * Copyright (c) 2012-2014 Apple Inc. All Rights Reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. Please obtain a copy of the License at 10 * http://www.opensource.apple.com/apsl/ and read it before using this 11 * file. 12 * 13 * The Original Code and all software distributed under the License are 14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 18 * Please see the License for the specific language governing rights and 19 * limitations under the License. 20 * 21 * @APPLE_LICENSE_HEADER_END@ 22 */ 23 24 25#include "utilities/SecCFRelease.h" 26#include "utilities/SecCFWrappers.h" 27#include "utilities/der_date.h" 28#include "utilities/der_plist.h" 29#include "utilities/der_plist_internal.h" 30 31#include <corecrypto/ccder.h> 32#include <CoreFoundation/CoreFoundation.h> 33#include <CoreFoundation/CFCalendar.h> 34#include <math.h> 35 36#define NULL_TIME NAN 37 38/* Cumulative number of days in the year for months up to month i. */ 39static int mdays[13] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 }; 40 41static CFAbsoluteTime SecGregorianDateGetAbsoluteTime(int year, int month, int day, int hour, int minute, int second, CFTimeInterval timeZoneOffset, CFErrorRef *error) { 42 int is_leap_year = year % 4 == 0 && (year % 100 != 0 || year % 400 == 0) ? 1 : 0; 43 if (month < 1 || month > 12 || day < 1 || day > 31 || hour >= 24 || minute >= 60 || second >= 60.0 44 || (month == 2 && day > mdays[month] - mdays[month - 1] + is_leap_year) 45 || (month != 2 && day > mdays[month] - mdays[month - 1])) { 46 /* Invalid date. */ 47 SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Invalid date."), 0, error); 48 return NULL_TIME; 49 } 50 51 int dy = year - 2001; 52 if (dy < 0) { 53 dy += 1; 54 day -= 1; 55 } 56 57 int leap_days = dy / 4 - dy / 100 + dy / 400; 58 day += ((year - 2001) * 365 + leap_days) + mdays[month - 1] - 1; 59 if (month > 2) 60 day += is_leap_year; 61 62 CFAbsoluteTime absTime = (CFAbsoluteTime)((day * 24 + hour) * 60 + minute) * 60 + second; 63 return absTime - timeZoneOffset; 64} 65 66static bool SecAbsoluteTimeGetGregorianDate(CFTimeInterval at, int *year, int *month, int *day, int *hour, int *minute, int *second, CFErrorRef *error) { 67 // TODO: Remove CFCalendarDecomposeAbsoluteTime dependancy because CFTimeZoneCreateWithTimeIntervalFromGMT is expensive and requires filesystem access to timezone files when we are only doing zulu time anyway 68 if (!CFCalendarDecomposeAbsoluteTime(SecCFCalendarGetZulu(), at, "yMdHms", year, month, day, hour, minute, second)) { 69 SecCFDERCreateError(kSecDERErrorUnknownEncoding, CFSTR("Failed to encode date."), 0, error); 70 return false; 71 } 72 return true; 73} 74 75static int der_get_char(const uint8_t **der_p, const uint8_t *der_end, 76 CFErrorRef *error) { 77 const uint8_t *der = *der_p; 78 if (!der) { 79 /* Don't create a new error in this case. */ 80 return -1; 81 } 82 83 if (der >= der_end) { 84 SecCFDERCreateError(kSecDERErrorUnknownEncoding, 85 CFSTR("Unexpected end of datetime"), 0, error); 86 *der_p = NULL; 87 return -1; 88 } 89 90 int ch = *der++; 91 *der_p = der; 92 return ch; 93} 94 95 96static int der_decode_decimal(const uint8_t **der_p, const uint8_t *der_end, 97 CFErrorRef *error) { 98 char ch = der_get_char(der_p, der_end, error); 99 if (ch < '0' || ch > '9') { 100 SecCFDERCreateError(kSecDERErrorUnknownEncoding, 101 CFSTR("Not a decimal digit"), 0, error); 102 *der_p = NULL; 103 return -1; 104 } 105 return ch - '0'; 106} 107 108static int der_decode_decimal_pair(const uint8_t **der_p, const uint8_t *der_end, 109 CFErrorRef *error) { 110 return (10 * der_decode_decimal(der_p, der_end, error)) 111 + der_decode_decimal(der_p, der_end, error); 112} 113 114static int der_peek_byte(const uint8_t *der, const uint8_t *der_end) { 115 if (!der || der >= der_end) 116 return -1; 117 118 return *der; 119} 120 121static const uint8_t *der_decode_decimal_fraction(double *fraction, CFErrorRef *error, 122 const uint8_t* der, const uint8_t *der_end) { 123 int ch = der_peek_byte(der, der_end); 124 if (ch == -1) { 125 der = NULL; 126 } else if (ch == '.') { 127 uint64_t divisor = 1; 128 uint64_t value = 0; 129 int last = -1; 130 while (++der < der_end) { 131 last = ch; 132 ch = *der; 133 if (ch < '0' || ch > '9') { 134 break; 135 } 136 if (divisor < UINT64_MAX / 10) { 137 divisor *= 10; 138 value *= 10; 139 value += (ch - '0'); 140 } 141 } 142 if (der >= der_end) 143 der = NULL; 144 else if (last == '0') { 145 SecCFDERCreateError(kSecDERErrorUnknownEncoding, 146 CFSTR("fraction ends in 0"), 0, error); 147 der = NULL; 148 } else if (last == '.') { 149 SecCFDERCreateError(kSecDERErrorUnknownEncoding, 150 CFSTR("fraction without digits"), 0, error); 151 der = NULL; 152 } else { 153 *fraction = (double)value / divisor; 154 } 155 } else { 156 *fraction = 0.0; 157 } 158 159 return der; 160} 161 162static const CFTimeInterval der_decode_timezone_offset(const uint8_t **der_p, 163 const uint8_t *der_end, 164 CFErrorRef *error) { 165 CFTimeInterval timeZoneOffset; 166 int ch = der_get_char(der_p, der_end, error); 167 if (ch == 'Z') { 168 /* Zulu time. */ 169 timeZoneOffset = 0.0; 170 } else { 171 /* ZONE INDICATOR */ 172 int multiplier; 173 if (ch == '-') 174 multiplier = -60; 175 else if (ch == '+') 176 multiplier = +60; 177 else { 178 SecCFDERCreateError(kSecDERErrorUnknownEncoding, 179 CFSTR("Invalid datetime character"), 0, error); 180 return NULL_TIME; 181 } 182 183 timeZoneOffset = multiplier * 184 (der_decode_decimal_pair(der_p, der_end, error) 185 * 60 + der_decode_decimal_pair(der_p, der_end, error)); 186 } 187 return timeZoneOffset; 188} 189 190static const uint8_t* der_decode_commontime_body(CFAbsoluteTime *at, CFErrorRef *error, int year, 191 const uint8_t* der, const uint8_t *der_end) 192{ 193 int month = der_decode_decimal_pair(&der, der_end, error); 194 int day = der_decode_decimal_pair(&der, der_end, error); 195 int hour = der_decode_decimal_pair(&der, der_end, error); 196 int minute = der_decode_decimal_pair(&der, der_end, error); 197 int second = der_decode_decimal_pair(&der, der_end, error); 198 double fraction; 199 der = der_decode_decimal_fraction(&fraction, error, der, der_end); 200 201 CFTimeInterval timeZoneOffset = der_decode_timezone_offset(&der, der_end, error); 202 203#if 0 204 secdebug("dateparse", 205 "date %.*s year: %04d%02d%02d%02d%02d%02d%+05g", 206 length, bytes, g.year, g.month, 207 g.day, g.hour, g.minute, g.second, 208 timeZoneOffset / 60); 209#endif 210 211 if (der) { 212 if (der != der_end) { 213 SecCFDERCreateError(kSecDERErrorUnknownEncoding, 214 CFSTR("trailing garbage at end of datetime"), 0, error); 215 return NULL; 216 } 217 218 *at = SecGregorianDateGetAbsoluteTime(year, month, day, hour, minute, second, timeZoneOffset, error) + fraction; 219 if (*at == NULL_TIME) 220 return NULL; 221 } 222 223 return der; 224} 225 226const uint8_t* der_decode_generalizedtime_body(CFAbsoluteTime *at, CFErrorRef *error, 227 const uint8_t* der, const uint8_t *der_end) 228{ 229 int year = 100 * der_decode_decimal_pair(&der, der_end, error) + der_decode_decimal_pair(&der, der_end, error); 230 return der_decode_commontime_body(at, error, year, der, der_end); 231} 232 233const uint8_t* der_decode_universaltime_body(CFAbsoluteTime *at, CFErrorRef *error, 234 const uint8_t* der, const uint8_t *der_end) 235{ 236 SInt32 year = der_decode_decimal_pair(&der, der_end, error); 237 if (year < 50) { 238 /* 0 <= year < 50 : assume century 21 */ 239 year += 2000; 240 } else if (year < 70) { 241 /* 50 <= year < 70 : illegal per PKIX */ 242 SecCFDERCreateError(kSecDERErrorUnknownEncoding, 243 CFSTR("Invalid universal time year between 50 and 70"), 0, error); 244 der = NULL; 245 } else { 246 /* 70 < year <= 99 : assume century 20 */ 247 year += 1900; 248 } 249 250 return der_decode_commontime_body(at, error, year, der, der_end); 251} 252 253const uint8_t* der_decode_date(CFAllocatorRef allocator, CFOptionFlags mutability, 254 CFDateRef* date, CFErrorRef *error, 255 const uint8_t* der, const uint8_t *der_end) 256{ 257 if (NULL == der) 258 return NULL; 259 260 der = ccder_decode_constructed_tl(CCDER_GENERALIZED_TIME, &der_end, der, der_end); 261 CFAbsoluteTime at = 0; 262 der = der_decode_generalizedtime_body(&at, error, der, der_end); 263 if (der) { 264 *date = CFDateCreate(allocator, at); 265 if (NULL == *date) { 266 SecCFDERCreateError(kSecDERErrorAllocationFailure, CFSTR("Failed to create date"), NULL, error); 267 return NULL; 268 } 269 } 270 return der; 271} 272 273extern char *__dtoa(double _d, int mode, int ndigits, int *decpt, int *sign, char **rve); 274extern void __freedtoa(char *); 275 276static size_t ccder_sizeof_nanoseconds(CFAbsoluteTime at) { 277 int dotoff; 278 int sign; 279 char *end; 280 char *str = __dtoa(at, 0, 0, &dotoff, &sign, &end); 281 ptrdiff_t len = end - str; 282 __freedtoa(str); 283 return len < dotoff ? 0 : len - dotoff; 284 //return len < dotoff ? 0 : len - dotoff > 9 ? 9 : len - dotoff; 285} 286 287size_t der_sizeof_generalizedtime_body(CFAbsoluteTime at, CFErrorRef *error) 288{ 289 size_t subsec_digits = ccder_sizeof_nanoseconds(at); 290 291 /* Generalized zulu time YYYYMMDDhhmmss[.ssss]Z */ 292 return subsec_digits ? 16 + subsec_digits : 15; 293} 294 295size_t der_sizeof_generalizedtime(CFAbsoluteTime at, CFErrorRef *error) 296{ 297 return ccder_sizeof(CCDER_GENERALIZED_TIME, 298 der_sizeof_generalizedtime_body(at, error)); 299} 300 301size_t der_sizeof_date(CFDateRef date, CFErrorRef *error) 302{ 303 return der_sizeof_generalizedtime(CFDateGetAbsoluteTime(date), error); 304} 305 306 307static uint8_t *ccder_encode_byte(uint8_t byte, 308 const uint8_t *der, uint8_t *der_end) { 309 if (der + 1 > der_end) { 310 return NULL; 311 } 312 *--der_end = byte; 313 return der_end; 314} 315 316static uint8_t *ccder_encode_decimal_pair(int v, const uint8_t *der, 317 uint8_t *der_end) { 318 if (der_end == NULL || der + 2 > der_end) { 319 return NULL; 320 } 321 assert(v < 100); 322 *--der_end = '0' + v % 10; 323 *--der_end = '0' + v / 10; 324 return der_end; 325} 326 327static uint8_t *ccder_encode_decimal_quad(int v, const uint8_t *der, 328 uint8_t *der_end) { 329 return ccder_encode_decimal_pair(v / 100, der, 330 ccder_encode_decimal_pair(v % 100, der, der_end)); 331} 332 333static uint8_t *ccder_encode_nanoseconds(CFAbsoluteTime at, const uint8_t *der, 334 uint8_t *der_end) { 335 int dotoff; 336 int sign; 337 char *end; 338 char *str = __dtoa(at, 0, 0, &dotoff, &sign, &end); 339 char *begin = str + (dotoff < 0 ? 0 : dotoff); 340 // Compute 1.0000000 - fraction in ascii space 341 if (at < 0.0 && begin < end) { 342 char *p = end - 1; 343 // Borrow for last digit 344 *p = ('9' + 1) - (*p - '0'); 345 while (p-- > begin) { 346 // Every other digit is a 9 since we borrowed from the last one 347 *p = '9' - (*p - '0'); 348 } 349 } 350 351 ptrdiff_t len = end - str; 352 if (len > dotoff) { 353 if (dotoff < 0) { 354 assert(-1.0 < at && at < 1.0); 355 der_end = ccder_encode_body(len, (const uint8_t *)str, der, der_end); 356 der_end = ccder_encode_body_nocopy(-dotoff, der, der_end); 357 if (der_end) 358 memset(der_end, at < 0.0 ? '9' : '0', -dotoff); 359 } else { 360 der_end = ccder_encode_body(len - dotoff, (const uint8_t *)(str + dotoff), der, der_end); 361 } 362 der_end = ccder_encode_byte('.', der, der_end); 363 } 364 __freedtoa(str); 365 366 return der_end; 367} 368 369/* Encode generalized zulu time YYYYMMDDhhmmss[.ssss]Z */ 370uint8_t* der_encode_generalizedtime_body(CFAbsoluteTime at, CFErrorRef *error, 371 const uint8_t *der, uint8_t *der_end) 372{ 373 int year = 0, month = 0, day = 0, hour = 0, minute = 0, second = 0; 374 if (!SecAbsoluteTimeGetGregorianDate(at, &year, &month, &day, &hour, &minute, &second, error)) 375 return NULL; 376 377 return ccder_encode_decimal_quad(year, der, 378 ccder_encode_decimal_pair(month, der, 379 ccder_encode_decimal_pair(day, der, 380 ccder_encode_decimal_pair(hour, der, 381 ccder_encode_decimal_pair(minute, der, 382 ccder_encode_decimal_pair(second, der, 383 ccder_encode_nanoseconds(at, der, 384 ccder_encode_byte('Z', der, der_end)))))))); 385} 386 387uint8_t* der_encode_generalizedtime(CFAbsoluteTime at, CFErrorRef *error, 388 const uint8_t *der, uint8_t *der_end) 389{ 390 return ccder_encode_constructed_tl(CCDER_GENERALIZED_TIME, der_end, der, 391 der_encode_generalizedtime_body(at, error, der, der_end)); 392} 393 394 395uint8_t* der_encode_date(CFDateRef date, CFErrorRef *error, 396 const uint8_t *der, uint8_t *der_end) 397{ 398 return der_encode_generalizedtime(CFDateGetAbsoluteTime(date), error, 399 der, der_end); 400} 401