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Robin Jones 2025-02-22 00:37:00 +00:00
parent 774c89cbfd
commit 2fe2a22eee
1 changed files with 76 additions and 3 deletions
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79
src/boot/cic.c
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@ -1,39 +1,101 @@
/**
* @file cic.c
* @brief CIC (Copy Protection) functions implementation
* @ingroup boot
*/
#include "cic.h"
/**
* @brief Get a 32-bit value from a byte array at the specified index.
*
* @param p Pointer to the byte array.
* @param index Index to get the value from.
* @return uint32_t The 32-bit value.
*/
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]);
}
/**
* @brief Add two 32-bit values.
*
* @param a1 First value.
* @param a2 Second value.
* @return uint32_t The result of the addition.
*/
static inline uint32_t _add (uint32_t a1, uint32_t a2) {
return a1 + a2;
}
/**
* @brief Subtract one 32-bit value from another.
*
* @param a1 First value.
* @param a2 Second value.
* @return uint32_t The result of the subtraction.
*/
static inline uint32_t _sub (uint32_t a1, uint32_t a2) {
return a1 - a2;
}
/**
* @brief Multiply two 32-bit values.
*
* @param a1 First value.
* @param a2 Second value.
* @return uint32_t The result of the multiplication.
*/
static inline uint32_t _mul (uint32_t a1, uint32_t a2) {
return a1 * a2;
}
/**
* @brief Rotate a 32-bit value left by a specified number of bits.
*
* @param a The value to rotate.
* @param s The number of bits to rotate.
* @return uint32_t The result of the rotation.
*/
static inline uint32_t _rol (uint32_t a, uint32_t s) {
return ((a) << (s)) | ((a) >> (-(s) & 31));
}
/**
* @brief Rotate a 32-bit value right by a specified number of bits.
*
* @param a The value to rotate.
* @param s The number of bits to rotate.
* @return uint32_t The result of the rotation.
*/
static inline uint32_t _ror (uint32_t a, uint32_t s) {
return ((a) >> (s)) | ((a) << (-(s) & 31));
}
/**
* @brief Calculate the sum of three 32-bit values.
*
* @param a0 First value.
* @param a1 Second value.
* @param a2 Third value.
* @return uint32_t The result of the sum.
*/
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;
};
}
/**
* @brief Calculate the IPL3 checksum for the CIC.
*
* @param ipl3 Pointer to the IPL3 data.
* @param seed The seed value.
* @return uint64_t The calculated checksum.
*/
static uint64_t cic_calculate_ipl3_checksum (uint8_t *ipl3, uint8_t seed) {
const uint32_t MAGIC = 0x6C078965;
@ -97,7 +159,12 @@ static uint64_t cic_calculate_ipl3_checksum (uint8_t *ipl3, uint8_t seed) {
return checksum;
}
/**
* @brief Detect the CIC type based on the IPL3 data.
*
* @param ipl3 Pointer to the IPL3 data.
* @return cic_type_t The detected CIC type.
*/
cic_type_t cic_detect (uint8_t *ipl3) {
switch (cic_calculate_ipl3_checksum(ipl3, 0x3F)) {
case 0x45CC73EE317AULL: return CIC_6101; // 6101
@ -127,6 +194,12 @@ cic_type_t cic_detect (uint8_t *ipl3) {
return CIC_UNKNOWN;
}
/**
* @brief Get the seed value for the specified CIC type.
*
* @param cic_type The CIC type.
* @return uint8_t The seed value.
*/
uint8_t cic_get_seed (cic_type_t cic_type) {
switch (cic_type) {
case CIC_5101: return 0xAC;