Replaced system SQLite with SQLCipher to support encrypted database

Sources/DataLiteC/libtomcrypt/prngs/rng_get_bytes.c

@@ -0,0 +1,173 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
+#include "tomcrypt_private.h"
+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wconversion"
+#pragma clang diagnostic ignored "-Wshorten-64-to-32"
+
+#ifdef LTC_RNG_GET_BYTES
+/**
+   @file rng_get_bytes.c
+   portable way to get secure random bits to feed a PRNG (Tom St Denis)
+*/
+
+#if defined(LTC_DEVRANDOM) && !defined(_WIN32)
+/* on *NIX read /dev/random */
+static unsigned long s_rng_nix(unsigned char *buf, unsigned long len,
+                             void (*callback)(void))
+{
+#ifdef LTC_NO_FILE
+    LTC_UNUSED_PARAM(callback);
+    LTC_UNUSED_PARAM(buf);
+    LTC_UNUSED_PARAM(len);
+    return 0;
+#else
+    FILE *f;
+    unsigned long x;
+    LTC_UNUSED_PARAM(callback);
+#ifdef LTC_TRY_URANDOM_FIRST
+    f = fopen("/dev/urandom", "rb");
+    if (f == NULL) {
+       f = fopen("/dev/random", "rb");
+    }
+#else
+    f = fopen("/dev/random", "rb");
+#endif /* LTC_TRY_URANDOM_FIRST */
+
+    if (f == NULL) {
+       return 0;
+    }
+
+    /* disable buffering */
+    if (setvbuf(f, NULL, _IONBF, 0) != 0) {
+       fclose(f);
+       return 0;
+    }
+
+    x = (unsigned long)fread(buf, 1, (size_t)len, f);
+    fclose(f);
+    return x;
+#endif /* LTC_NO_FILE */
+}
+
+#endif /* LTC_DEVRANDOM */
+
+#if !defined(_WIN32_WCE)
+
+#define ANSI_RNG
+
+static unsigned long s_rng_ansic(unsigned char *buf, unsigned long len,
+                               void (*callback)(void))
+{
+   clock_t t1;
+   int l, acc, bits, a, b;
+
+   l = len;
+   bits = 8;
+   acc  = a = b = 0;
+   while (len--) {
+       if (callback != NULL) callback();
+       while (bits--) {
+          do {
+             t1 = XCLOCK(); while (t1 == XCLOCK()) a ^= 1;
+             t1 = XCLOCK(); while (t1 == XCLOCK()) b ^= 1;
+          } while (a == b);
+          acc = (acc << 1) | a;
+       }
+       *buf++ = acc;
+       acc  = 0;
+       bits = 8;
+   }
+   return l;
+}
+
+#endif
+
+/* Try the Microsoft CSP */
+#if defined(_WIN32) || defined(_WIN32_WCE)
+#if defined(LTC_WIN32_BCRYPT)
+
+#include <windows.h>
+#include <bcrypt.h>
+#pragma comment(lib, "bcrypt.lib")
+
+static unsigned long s_rng_win32(unsigned char *buf, unsigned long len,
+                               void (*callback)(void))
+{
+   LTC_UNUSED_PARAM(callback);
+
+   return BCRYPT_SUCCESS(BCryptGenRandom(NULL, (PUCHAR)buf, (ULONG)len, BCRYPT_USE_SYSTEM_PREFERRED_RNG)) ? len : 0;
+}
+
+#else
+
+#ifndef _WIN32_WINNT
+  #define _WIN32_WINNT 0x0501
+#endif
+#ifndef WINVER
+  #define WINVER 0x0501
+#endif
+
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#include <wincrypt.h>
+
+static unsigned long s_rng_win32(unsigned char *buf, unsigned long len,
+                               void (*callback)(void))
+{
+   static HCRYPTPROV hProv = 0;
+   LTC_UNUSED_PARAM(callback);
+
+   if (hProv == 0) {
+      HCRYPTPROV h = 0;
+      if (!CryptAcquireContextW(&h, NULL, MS_DEF_PROV_W, PROV_RSA_FULL,
+                                (CRYPT_VERIFYCONTEXT | CRYPT_MACHINE_KEYSET)) &&
+          !CryptAcquireContextW(&h, NULL, MS_DEF_PROV_W, PROV_RSA_FULL,
+                                CRYPT_VERIFYCONTEXT | CRYPT_MACHINE_KEYSET | CRYPT_NEWKEYSET)) {
+         return 0;
+      }
+      hProv = h;
+   }
+
+   return CryptGenRandom(hProv, (DWORD)len, (BYTE *)buf) == TRUE ? len : 0;
+}
+#endif /* Old WIN32 versions */
+#endif /* WIN32 */
+
+/**
+  Read the system RNG
+  @param out       Destination
+  @param outlen    Length desired (octets)
+  @param callback  Pointer to void function to act as "callback" when RNG is slow.  This can be NULL
+  @return Number of octets read
+*/
+unsigned long rng_get_bytes(unsigned char *out, unsigned long outlen,
+                            void (*callback)(void))
+{
+   unsigned long x;
+
+   LTC_ARGCHK(out != NULL);
+
+#ifdef LTC_PRNG_ENABLE_LTC_RNG
+   if (ltc_rng) {
+      x = ltc_rng(out, outlen, callback);
+      if (x != 0) {
+         return x;
+      }
+   }
+#endif
+
+#if defined(_WIN32) || defined(_WIN32_WCE)
+   x = s_rng_win32(out, outlen, callback); if (x != 0) { return x; }
+#elif defined(LTC_DEVRANDOM)
+   x = s_rng_nix(out, outlen, callback);   if (x != 0) { return x; }
+#endif
+#ifdef ANSI_RNG
+   x = s_rng_ansic(out, outlen, callback); if (x != 0) { return x; }
+#endif
+   return 0;
+}
+#endif /* #ifdef LTC_RNG_GET_BYTES */
+
+#pragma clang diagnostic pop