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Move source files to src/, add Makefile, fix all build and linkage errors, etc.

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TuxSH 2018-02-25 20:00:50 +01:00
parent 4c7aa566f0
commit b0ea9c1a0b
58 changed files with 385 additions and 203 deletions
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73
exosphere/src/randomcache.c Normal file
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#include <stdint.h>
#include <string.h>
#include "utils.h"
#include "randomcache.h"
#include "se.h"
#include "cache.h"
/* TrustZone maintains a cache of random for the kernel. */
/* So that requests can still be serviced even when a */
/* usermode SMC is in progress. */
static uint8_t g_random_cache[0x400];
static unsigned int g_random_cache_low = 0;
static unsigned int g_random_cache_high = 0x3FF;
void randomcache_refill_segment(unsigned int offset, unsigned int size) {
if (offset + size >= 0x400) {
size = 0x400 - offset;
}
flush_dcache_range(&g_random_cache[offset], &g_random_cache[offset + size]);
se_generate_random(KEYSLOT_SWITCH_RNGKEY, &g_random_cache[offset], size);
flush_dcache_range(&g_random_cache[offset], &g_random_cache[offset + size]);
}
void randomcache_init(void) {
randomcache_refill_segment(0, 0x400);
g_random_cache_low = 0;
g_random_cache_high = 0x3FF;
}
void randomcache_refill(void) {
unsigned int high_plus_one = (g_random_cache_high + 1) & 0x3FF;
if (g_random_cache_low != high_plus_one) {
/* Only refill if there's data to refill. */
if (g_random_cache_low < high_plus_one) {
/* NOTE: There is a bug in official code that causes this to not work properly. */
/* In particular, official code checks whether high_plus_one == 0x400. */
/* However, because high_plus_one is &= 0x3FF'd, this can never be the case. */
/* We will implement according to Nintendo's intention, and not include their bug. */
/* This should have no impact on actual observable results, anyway, since this data is random anyway... */
if (g_random_cache_high != 0x3FF) { /* This is if (true) in Nintendo's code due to the above bug. */
randomcache_refill_segment(high_plus_one, 0x400 - high_plus_one);
g_random_cache_high = (g_random_cache_high + 0x400 - high_plus_one) & 0x3FF;
}
if (g_random_cache_low > 0) {
randomcache_refill_segment(0, g_random_cache_low);
g_random_cache_high = (g_random_cache_high + g_random_cache_low) & 0x3FF;
}
} else { /* g_random_cache_low > high_plus_one */
randomcache_refill_segment(high_plus_one, g_random_cache_low - high_plus_one);
g_random_cache_high = g_random_cache_low - 1;
}
}
}
void randomcache_getbytes(void *dst, size_t num_bytes) {
unsigned int low = g_random_cache_low;
memcpy(dst, &g_random_cache[low], num_bytes);
unsigned int new_low = low + num_bytes;
if (new_low + 0x38 > 0x3FF) {
new_low = 0;
}
g_random_cache_low = new_low;
}