From 8e50e4c1e110f3fcde5331d5d435c9e497be2936 Mon Sep 17 00:00:00 2001 From: Mateusz Faderewski Date: Thu, 7 Dec 2023 00:36:16 +0100 Subject: [PATCH] Improved CIC detection algorithm Now it incorporates the same algorithm as is included in the N64 IPL2. IPL3 that have checksum collision are now correctly detected. --- Makefile | 1 - src/boot/cic.c | 143 ++++++++++++++++++++++++++++++++++++++--------- src/boot/crc32.c | 50 ----------------- src/boot/crc32.h | 18 ------ 4 files changed, 118 insertions(+), 94 deletions(-) delete mode 100644 src/boot/crc32.c delete mode 100644 src/boot/crc32.h diff --git a/Makefile b/Makefile index 807aad07..25a7d14a 100644 --- a/Makefile +++ b/Makefile @@ -17,7 +17,6 @@ SRCS = \ main.c \ boot/boot.c \ boot/cic.c \ - boot/crc32.c \ boot/reboot.S \ flashcart/64drive/64drive_ll.c \ flashcart/64drive/64drive.c \ diff --git a/src/boot/cic.c b/src/boot/cic.c index 6b74d217..54455030 100644 --- a/src/boot/cic.c +++ b/src/boot/cic.c @@ -1,36 +1,129 @@ #include "cic.h" -#include "crc32.h" -typedef struct { - const uint32_t crc32; - const cic_type_t type; -} ipl3_crc32_t; +static inline uint32_t _get (uint8_t *p, int index) { + int i = index * 4; + return (p[i] << 24 | p[i + 1] << 16 | p[i + 2] << 8 | p[i + 3]); +} -static const ipl3_crc32_t ipl3_crc32[] = { - { .crc32 = 0x587BD543, .type = CIC_5101 }, - { .crc32 = 0x0E018159, .type = CIC_5167 }, - { .crc32 = 0x6170A4A1, .type = CIC_6101 }, - { .crc32 = 0x009E9EA3, .type = CIC_7102 }, - { .crc32 = 0x90BB6CB5, .type = CIC_6102_7101 }, - { .crc32 = 0x0B050EE0, .type = CIC_x103 }, - { .crc32 = 0x98BC2C86, .type = CIC_x105 }, - { .crc32 = 0xACC8580A, .type = CIC_x106 }, - { .crc32 = 0xBC605D0A, .type = CIC_8301 }, - { .crc32 = 0x502C4466, .type = CIC_8302 }, - { .crc32 = 0x0C965795, .type = CIC_8303 }, - { .crc32 = 0x10C68B18, .type = CIC_8401 }, - { .crc32 = 0x8FEBA21E, .type = CIC_8501 }, +static inline uint32_t _add (uint32_t a1, uint32_t a2) { + return a1 + a2; +} + +static inline uint32_t _sub (uint32_t a1, uint32_t a2) { + return a1 - a2; +} + +static inline uint32_t _mul (uint32_t a1, uint32_t a2) { + return a1 * a2; +} + +static inline uint32_t _rol (uint32_t a, uint32_t s) { + return ((a) << (s)) | ((a) >> (-(s) & 31)); +} + +static inline uint32_t _ror (uint32_t a, uint32_t s) { + return ((a) >> (s)) | ((a) << (-(s) & 31)); +} + +static uint32_t _sum (uint32_t a0, uint32_t a1, uint32_t a2) { + uint64_t prod = ((uint64_t) (a0)) * (a1 == 0 ? a2 : a1); + uint32_t hi = (prod >> 32) & 0xFFFFFFFF; + uint32_t lo = prod & 0xFFFFFFFF; + uint32_t diff = hi - lo; + return (diff == 0) ? a0 : diff; }; +static uint64_t cic_calculate_ipl3_checksum (uint8_t *ipl3, uint8_t seed) { + const uint32_t MAGIC = 0x6C078965; + + uint32_t data, prev, next; + data = prev = next = _get(ipl3, 0); + + uint32_t init = _add(_mul(MAGIC, seed), 1) ^ data; + + uint32_t buf[16]; + for (int i = 0; i < 16; i++) { + buf[i] = init; + } + + for (int i = 1; i <= 1008; i++) { + prev = data; + data = next; + + buf[0] = _add(buf[0], _sum(_sub(1007, i), data, i)); + buf[1] = _sum(buf[1], data, i); + buf[2] = buf[2] ^ data; + buf[3] = _add(buf[3], _sum(_add(data, 5), MAGIC, i)); + buf[4] = _add(buf[4], _ror(data, prev & 0x1F)); + buf[5] = _add(buf[5], _rol(data, prev >> 27)); + buf[6] = (data < buf[6]) ? (_add(buf[3], buf[6]) ^ _add(data, i)) : (_add(buf[4], data) ^ buf[6]); + buf[7] = _sum(buf[7], _rol(data, prev & 0x1F), i); + buf[8] = _sum(buf[8], _ror(data, prev >> 27), i); + buf[9] = (prev < data) ? _sum(buf[9], data, i) : _add(buf[9], data); + + if (i == 1008) { + break; + } + + next = _get(ipl3, i); + buf[10] = _sum(_add(buf[10], data), next, i); + buf[11] = _sum(buf[11] ^ data, next, i); + buf[12] = _add(buf[12], buf[8] ^ data); + buf[13] = _add(buf[13], _add(_ror(data, data & 0x1F), _ror(next, next & 0x1F))); + buf[14] = _sum(_sum(buf[14], _ror(data, prev & 0x1F), i), _ror(next, data & 0x1F), i); + buf[15] = _sum(_sum(buf[15], _rol(data, prev >> 27), i), _rol(next, data >> 27), i); + } + + uint32_t final_buf[4]; + for (int i = 0; i < 4; i++) { + final_buf[i] = buf[0]; + } + + for (int i = 0; i < 16; i++) { + uint32_t data = buf[i]; + final_buf[0] = _add(final_buf[0], _ror(data, data & 0x1F)); + final_buf[1] = (data < final_buf[0]) ? _add(final_buf[1], data) : _sum(final_buf[1], data, i); + final_buf[2] = (((data & 0x02) >> 1) == (data & 0x01)) ? _add(final_buf[2], data) : _sum(final_buf[2], data, i); + final_buf[3] = ((data & 0x01) == 0x01) ? (final_buf[3] ^ data) : _sum(final_buf[3], data, i); + } + + uint32_t final_sum = _sum(final_buf[0], final_buf[1], 16); + uint32_t final_xor = final_buf[3] ^ final_buf[2]; + + uint64_t checksum = (((((uint64_t) (final_sum)) & 0xFFFF)) << 32) | (final_xor); + + return checksum; +} + cic_type_t cic_detect (uint8_t *ipl3) { - uint32_t crc32 = crc32_calculate(ipl3, IPL3_LENGTH); - - for (int i = 0; i < sizeof(ipl3_crc32) / sizeof(ipl3_crc32_t); i++) { - if (ipl3_crc32[i].crc32 == crc32) { - return ipl3_crc32[i].type; - } + switch (cic_calculate_ipl3_checksum(ipl3, 0x3F)) { + case 0x45CC73EE317AULL: return CIC_6101; // 6101 + case 0x44160EC5D9AFULL: return CIC_7102; // 7102 + case 0xA536C0F1D859ULL: return CIC_6102_7101; // 6102 / 7101 + } + switch (cic_calculate_ipl3_checksum(ipl3, 0x78)) { + case 0x586FD4709867ULL: return CIC_x103; // 6103 / 7103 + } + switch (cic_calculate_ipl3_checksum(ipl3, 0x85)) { + case 0x2BBAD4E6EB74ULL: return CIC_x106; // 6106 / 7106 + } + switch (cic_calculate_ipl3_checksum(ipl3, 0x91)) { + case 0x8618A45BC2D3ULL: return CIC_x105; // 6105 / 7105 + } + switch (cic_calculate_ipl3_checksum(ipl3, 0xAC)) { + case 0x5930D81014DAULL: return CIC_5101; // Aleck 64 + } + switch (cic_calculate_ipl3_checksum(ipl3, 0xDD)) { + case 0x6EE8D9E84970ULL: return CIC_8401; // NDXJ0 + case 0x6C216495C8B9ULL: return CIC_8301; // NDDJ0 + case 0xE27F43BA93ACULL: return CIC_8302; // NDDJ1 + case 0x32B294E2AB90ULL: return CIC_8303; // NDDJ2 + case 0x083C6C77E0B1ULL: return CIC_5167; // 64DD Cartridge conversion + } + switch (cic_calculate_ipl3_checksum(ipl3, 0xDE)) { + case 0x05BA2EF0A5F1ULL: return CIC_8501; // NDDE0 } return CIC_UNKNOWN; diff --git a/src/boot/crc32.c b/src/boot/crc32.c deleted file mode 100644 index 20685620..00000000 --- a/src/boot/crc32.c +++ /dev/null @@ -1,50 +0,0 @@ -#include "crc32.h" - - -static const uint32_t crc32_table[256] = { - 0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3, - 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, - 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, - 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5, - 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, - 0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, - 0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F, - 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, - 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433, - 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01, - 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, - 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65, - 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, - 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, - 0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F, - 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD, - 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, - 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1, - 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7, - 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, - 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B, - 0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79, - 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, - 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D, - 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713, - 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, - 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777, - 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, - 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, - 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9, - 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF, - 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D, -}; - - -uint32_t crc32_calculate (void *buffer, size_t length) { - uint32_t crc32 = 0xFFFFFFFFUL; - - uint8_t *byte_pointer = (uint8_t *) (buffer); - - while (length--) { - crc32 = (crc32 >> 8) ^ crc32_table[(crc32 & 0xFF) ^ (*byte_pointer++)]; - } - - return ~(crc32); -} diff --git a/src/boot/crc32.h b/src/boot/crc32.h deleted file mode 100644 index 85ad535d..00000000 --- a/src/boot/crc32.h +++ /dev/null @@ -1,18 +0,0 @@ -/** - * @file crc32.h - * @brief Flashcart Boot Checksum - * @ingroup boot - */ - -#ifndef CRC32_H__ -#define CRC32_H__ - - -#include -#include - - -uint32_t crc32_calculate (void *buffer, size_t length); - - -#endif