lokinet/llarp/win32/libsodium-1.0.17-win32.patch

diff --git a/src/libsodium/randombytes/salsa20/randombytes_salsa20_random.c b/src/libsodium/randombytes/salsa20/randombytes_salsa20_random.c
index 64c4cec5..42d02235 100644
--- a/src/libsodium/randombytes/salsa20/randombytes_salsa20_random.c
+++ b/src/libsodium/randombytes/salsa20/randombytes_salsa20_random.c
@@ -58,15 +58,13 @@
 #ifdef _WIN32
 # include <windows.h>
 # include <sys/timeb.h>
-# define RtlGenRandom SystemFunction036
-# if defined(__cplusplus)
-extern "C"
-# endif
-BOOLEAN NTAPI RtlGenRandom(PVOID RandomBuffer, ULONG RandomBufferLength);
-# pragma comment(lib, "advapi32.lib")
+# include <wincrypt.h>
+# include <bcrypt.h>
+ typedef NTSTATUS(FAR PASCAL *CNGAPI_DRBG)(BCRYPT_ALG_HANDLE, UCHAR *, ULONG,
+                                          ULONG);
 # ifdef __BORLANDC__
-#  define _ftime ftime
-#  define _timeb timeb
+# define _ftime ftime
+# define _timeb timeb
 # endif
 #endif
 
@@ -373,11 +371,44 @@ randombytes_salsa20_random_stir(void)
 # endif
 
 #else /* _WIN32 */
-    if (! RtlGenRandom((PVOID) stream.key, (ULONG) sizeof stream.key)) {
-        sodium_misuse(); /* LCOV_EXCL_LINE */
+  HANDLE hCAPINg;
+  BOOL rtld;
+  CNGAPI_DRBG getrandom;
+  HCRYPTPROV hProv;
+  /* load bcrypt dynamically, see if we're already loaded */
+  rtld    = FALSE;
+  hCAPINg = GetModuleHandle("bcrypt.dll");
+  /* otherwise, load CNG manually */
+  if(!hCAPINg)
+  {
+    hCAPINg = LoadLibraryEx("bcrypt.dll", NULL, LOAD_LIBRARY_SEARCH_SYSTEM32);
+    rtld    = TRUE;
+  }
+  if(hCAPINg)
+  {
+    /* call BCryptGenRandom(2) */
+    getrandom = (CNGAPI_DRBG)GetProcAddress(hCAPINg, "BCryptGenRandom");
+   if(!BCRYPT_SUCCESS(
+           getrandom(NULL, stream.key, sizeof stream.key, BCRYPT_USE_SYSTEM_PREFERRED_RNG)))
+    {
+      sodium_misuse();
     }
+   /* don't leak lib refs */
+    if(rtld)
+      FreeLibrary(hCAPINg);
+  }
+  /* if that fails use the regular ARC4-SHA1 RNG (!!!) *cringes* */
+  else
+  {
+    CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_FULL,
+                        CRYPT_VERIFYCONTEXT | CRYPT_SILENT);
+    if(!CryptGenRandom(hProv, sizeof stream.key, stream.key))
+    {
+      sodium_misuse(); /* LCOV_EXCL_LINE */
+    }
+    CryptReleaseContext(hProv, 0);
+  }
 #endif
-
     stream.initialized = 1;
 }
 
diff --git a/src/libsodium/randombytes/sysrandom/randombytes_sysrandom.c b/src/libsodium/randombytes/sysrandom/randombytes_sysrandom.c
index 99018f35..e2cacfb9 100644
--- a/src/libsodium/randombytes/sysrandom/randombytes_sysrandom.c
+++ b/src/libsodium/randombytes/sysrandom/randombytes_sysrandom.c
@@ -48,28 +48,12 @@
 #include "utils.h"
 
 #ifdef _WIN32
-/* `RtlGenRandom` is used over `CryptGenRandom` on Microsoft Windows based systems:
- *  - `CryptGenRandom` requires pulling in `CryptoAPI` which causes unnecessary
- *     memory overhead if this API is not being used for other purposes
- *  - `RtlGenRandom` is thus called directly instead. A detailed explanation
- *     can be found here: https://blogs.msdn.microsoft.com/michael_howard/2005/01/14/cryptographically-secure-random-number-on-windows-without-using-cryptoapi/
- *
- * In spite of the disclaimer on the `RtlGenRandom` documentation page that was
- * written back in the Windows XP days, this function is here to stay. The CRT
- * function `rand_s()` directly depends on it, so touching it would break many
- * applications released since Windows XP.
- *
- * Also note that Rust, Firefox and BoringSSL (thus, Google Chrome and everything
- * based on Chromium) also depend on it, and that libsodium allows the RNG to be
- * replaced without patching nor recompiling the library.
- */
 # include <windows.h>
-# define RtlGenRandom SystemFunction036
-# if defined(__cplusplus)
-extern "C"
-# endif
-BOOLEAN NTAPI RtlGenRandom(PVOID RandomBuffer, ULONG RandomBufferLength);
-# pragma comment(lib, "advapi32.lib")
+# include <sys/timeb.h>
+# include <wincrypt.h>
+# include <bcrypt.h>
+ typedef NTSTATUS(FAR PASCAL *CNGAPI_DRBG)(BCRYPT_ALG_HANDLE, UCHAR *, ULONG,
+                                           ULONG);
 #endif
 
 #if defined(__OpenBSD__) || defined(__CloudABI__)
@@ -359,9 +343,43 @@ randombytes_sysrandom_buf(void * const buf, const size_t size)
     if (size > (size_t) 0xffffffffUL) {
         sodium_misuse(); /* LCOV_EXCL_LINE */
     }
-    if (! RtlGenRandom((PVOID) buf, (ULONG) size)) {
-        sodium_misuse(); /* LCOV_EXCL_LINE */
+  HANDLE hCAPINg;
+  BOOL rtld;
+  CNGAPI_DRBG getrandom;
+  HCRYPTPROV hProv;
+  /* load bcrypt dynamically, see if we're already loaded */
+  rtld    = FALSE;
+  hCAPINg = GetModuleHandle("bcrypt.dll");
+  /* otherwise, load CNG manually */
+  if(!hCAPINg)
+  {
+    hCAPINg = LoadLibraryEx("bcrypt.dll", NULL, LOAD_LIBRARY_SEARCH_SYSTEM32);
+    rtld    = TRUE;
+  }
+  if(hCAPINg)
+  {
+    /* call BCryptGenRandom(2) */
+    getrandom = (CNGAPI_DRBG)GetProcAddress(hCAPINg, "BCryptGenRandom");
+   if(!BCRYPT_SUCCESS(
+           getrandom(NULL, buf, size, BCRYPT_USE_SYSTEM_PREFERRED_RNG)))
+    {
+      sodium_misuse();
+    }
+   /* don't leak lib refs */
+    if(rtld)
+      FreeLibrary(hCAPINg);
+  }
+  /* if that fails use the regular ARC4-SHA1 RNG (!!!) *cringes* */
+  else
+  {
+    CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_FULL,
+                        CRYPT_VERIFYCONTEXT | CRYPT_SILENT);
+    if(!CryptGenRandom(hProv, size, buf))
+    {
+      sodium_misuse(); /* LCOV_EXCL_LINE */
     }
+    CryptReleaseContext(hProv, 0);
+  }
 # endif /* _WIN32 */
 }