add encrypting for save files

add libhydrogen for encrypting and decrypting #9
2026-04-03 14:59:37 +02:00
parent abb6556fd4
commit c277ab10d9
68 changed files with 5737 additions and 74 deletions
@@ -0,0 +1,162 @@
+static TLS struct {
+    _hydro_attr_aligned_(16) uint8_t state[gimli_BLOCKBYTES];
+    uint64_t counter;
+    uint8_t  initialized;
+    uint8_t  available;
+} hydro_random_context;
+
+#if defined(AVR) && !defined(__unix__)
+#    include "random/avr.h"
+#elif (defined(ESP32) || defined(ESP8266)) && !defined(__unix__)
+#    include "random/esp32.h"
+#elif defined(PARTICLE) && defined(PLATFORM_ID) && PLATFORM_ID > 2 && !defined(__unix__)
+#    include "random/particle.h"
+#elif defined(__ZEPHYR__)
+#    include "random/zephyr.h"
+#elif (defined(NRF52832_XXAA) || defined(NRF52832_XXAB)) && !defined(__unix__)
+#    include "random/nrf52832.h"
+#elif defined(_WIN32)
+#    include "random/windows.h"
+#elif defined(__wasi__)
+#    include "random/wasi.h"
+#elif defined(__linux__) && defined(__KERNEL__)
+#    include "random/linux_kernel.h"
+#elif defined(__unix__)
+#    include "random/unix.h"
+#elif defined(TARGET_LIKE_MBED)
+#    include "random/mbed.h"
+#elif defined(RIOT_VERSION)
+#    include "random/riot.h"
+#elif defined(STM32F4) || defined(STM32L4)
+#    include "random/stm32.h"
+#elif defined(__RTTHREAD__)
+#    include "random/rtthread.h"
+#elif defined(CH32V30x_D8) || defined(CH32V30x_D8C)
+#    include "random/ch32.h"
+#elif defined(CHIBIOS)
+#    include "random/chibios.h"
+#elif defined(__CHERIOT__)
+#    include "random/cheriot.h"
+#elif defined(PICO_BUILD)
+#    ifndef LIB_PICO_RAND
+#        error pico-sdk detected but pico_rand not configured
+#    endif
+#    include "random/pico-sdk.h"
+#else
+#    error Unsupported platform
+#endif
+
+static void
+hydro_random_ensure_initialized(void)
+{
+    if (hydro_random_context.initialized == 0) {
+        if (hydro_random_init() != 0) {
+            abort();
+        }
+        gimli_core_u8(hydro_random_context.state, 0);
+        hydro_random_ratchet();
+        hydro_random_context.initialized = 1;
+    }
+}
+
+void
+hydro_random_ratchet(void)
+{
+    mem_zero(hydro_random_context.state, gimli_RATE);
+    STORE64_LE(hydro_random_context.state, hydro_random_context.counter);
+    hydro_random_context.counter++;
+    gimli_core_u8(hydro_random_context.state, 0);
+    hydro_random_context.available = gimli_RATE;
+}
+
+uint32_t
+hydro_random_u32(void)
+{
+    uint32_t v;
+
+    hydro_random_ensure_initialized();
+    if (hydro_random_context.available < 4) {
+        hydro_random_ratchet();
+    }
+    memcpy(&v, &hydro_random_context.state[gimli_RATE - hydro_random_context.available], 4);
+    hydro_random_context.available -= 4;
+
+    return v;
+}
+
+uint32_t
+hydro_random_uniform(const uint32_t upper_bound)
+{
+    uint32_t min;
+    uint32_t r;
+
+    if (upper_bound < 2U) {
+        return 0;
+    }
+    min = (1U + ~upper_bound) % upper_bound; /* = 2**32 mod upper_bound */
+    do {
+        r = hydro_random_u32();
+    } while (r < min);
+    /* r is now clamped to a set whose size mod upper_bound == 0
+     * the worst case (2**31+1) requires 2 attempts on average */
+
+    return r % upper_bound;
+}
+
+void
+hydro_random_buf(void *out, size_t out_len)
+{
+    uint8_t *p = (uint8_t *) out;
+    size_t   i;
+    size_t   leftover;
+
+    hydro_random_ensure_initialized();
+    for (i = 0; i < out_len / gimli_RATE; i++) {
+        gimli_core_u8(hydro_random_context.state, 0);
+        memcpy(p + i * gimli_RATE, hydro_random_context.state, gimli_RATE);
+    }
+    leftover = out_len % gimli_RATE;
+    if (leftover != 0) {
+        gimli_core_u8(hydro_random_context.state, 0);
+        mem_cpy(p + i * gimli_RATE, hydro_random_context.state, leftover);
+    }
+    hydro_random_ratchet();
+}
+
+void
+hydro_random_buf_deterministic(void *out, size_t out_len,
+                               const uint8_t seed[hydro_random_SEEDBYTES])
+{
+    static const uint8_t             prefix[] = { 7, 'd', 'r', 'b', 'g', '2', '5', '6' };
+    _hydro_attr_aligned_(16) uint8_t state[gimli_BLOCKBYTES];
+    uint8_t                         *p = (uint8_t *) out;
+    size_t                           i;
+    size_t                           leftover;
+
+    mem_zero(state, gimli_BLOCKBYTES);
+    COMPILER_ASSERT(sizeof prefix + 8 <= gimli_RATE);
+    memcpy(state, prefix, sizeof prefix);
+    STORE64_LE(state + sizeof prefix, (uint64_t) out_len);
+    gimli_core_u8(state, 1);
+    COMPILER_ASSERT(hydro_random_SEEDBYTES == gimli_RATE * 2);
+    mem_xor(state, seed, gimli_RATE);
+    gimli_core_u8(state, 2);
+    mem_xor(state, seed + gimli_RATE, gimli_RATE);
+    gimli_core_u8(state, 2);
+    for (i = 0; i < out_len / gimli_RATE; i++) {
+        gimli_core_u8(state, 0);
+        memcpy(p + i * gimli_RATE, state, gimli_RATE);
+    }
+    leftover = out_len % gimli_RATE;
+    if (leftover != 0) {
+        gimli_core_u8(state, 0);
+        mem_cpy(p + i * gimli_RATE, state, leftover);
+    }
+}
+
+void
+hydro_random_reseed(void)
+{
+    hydro_random_context.initialized = 0;
+    hydro_random_ensure_initialized();
+}