From 0673f231f333179d4698877ec40cdf43bf5b77c1 Mon Sep 17 00:00:00 2001
From: Steve Lhomme <robux4@ycbcr.xyz>
Date: Fri, 19 Jun 2020 10:37:50 +0200
Subject: [PATCH 5/5] random: only use wincrypt in UWP builds if WINSTORECOMPAT
 is set

This is a compatibility library to use older APIs that are forbidden in UWP apps.

bcrypt is supposed to be used instead of wincrypt but is only available since
Vista.
---
 random/rndw32.c | 22 ++++++++++++++++++++--
 src/Makefile.am |  4 +++-
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/random/rndw32.c b/random/rndw32.c
index 02d20cc3..f1b559e9 100644
--- a/random/rndw32.c
+++ b/random/rndw32.c
@@ -97,7 +97,11 @@
 #define SIZEOF_DISK_PERFORMANCE_STRUCT 256
 
 /* We don't include wincrypt.h so define it here.  */
+#if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) && defined(WINSTORECOMPAT)
+#include <wincrypt.h>
+#else
 #define HCRYPTPROV  HANDLE
+#endif
 
 
 /* When we query the performance counters, we allocate an initial buffer and
@@ -114,7 +118,7 @@
 
 /* Intel Chipset CSP type and name */
 #define PROV_INTEL_SEC  22
-#define INTEL_DEF_PROV  "Intel Hardware Cryptographic Service Provider"
+#define INTEL_DEF_PROV  TEXT("Intel Hardware Cryptographic Service Provider")
 
 
 
@@ -258,8 +262,9 @@ static void
 init_system_rng (void)
 {
   system_rng_available = 0;
-  hRNGProv = NULL;
+  hRNGProv = (HCRYPTPROV)NULL;
 
+#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)
   hAdvAPI32 = GetModuleHandle ("AdvAPI32.dll");
   if (!hAdvAPI32)
     return;
@@ -275,6 +280,19 @@ init_system_rng (void)
      This isn't exported by name, so we have to get it by ordinal.  */
   pRtlGenRandom = (RTLGENRANDOM)
     GetProcAddress (hAdvAPI32, "SystemFunction036");
+#elif defined(WINSTORECOMPAT)
+  hAdvAPI32 = NULL;
+  pCryptAcquireContext = CryptAcquireContextW;
+  pCryptGenRandom = CryptGenRandom;
+  pCryptReleaseContext = CryptReleaseContext;
+  pRtlGenRandom = NULL;
+#else /* !WINAPI_PARTITION_DESKTOP && !WINSTORECOMPAT */
+  hAdvAPI32 = NULL;
+  pCryptAcquireContext = NULL;
+  pCryptGenRandom = NULL;
+  pCryptReleaseContext = NULL;
+  pRtlGenRandom = NULL;
+#endif /* WINSTORECOMPAT */
 
   /* Try and connect to the PIII RNG CSP.  The AMD 768 southbridge (from
      the 760 MP chipset) also has a hardware RNG, but there doesn't appear
diff --git a/src/Makefile.am b/src/Makefile.am
index aa3548f6..154b35c7 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -126,7 +126,9 @@ libgcrypt_la_LIBADD = $(gcrypt_res) \
 	../random/librandom.la \
 	../mpi/libmpi.la \
 	../compat/libcompat.la $(DL_LIBS) $(GPG_ERROR_LIBS)
-
+if HAVE_W32_SYSTEM
+libgcrypt_la_LIBADD += -lbcrypt
+endif
 
 dumpsexp_SOURCES = dumpsexp.c
 dumpsexp_CFLAGS = $(arch_gpg_error_cflags)
-- 
2.37.3.windows.1