From 7f8b36b074b953ecf133b64c63caaaaf8017739a Mon Sep 17 00:00:00 2001
From: Don <don.j.olmstead@gmail.com>
Date: Tue, 28 Jun 2022 15:33:25 -0700
Subject: [PATCH] cmake: support ngtcp2 boringssl backend

Update the ngtcp2 find module to detect the boringssl backend. Determine
if the underlying OpenSSL implementation is BoringSSL and if so use that
as the ngtcp2 backend.

Reviewed-by: Jakub Zakrzewski
Closes #9065
---
 CMake/FindNGTCP2.cmake | 2 +-
 CMakeLists.txt         | 9 +++++++--
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/CMake/FindNGTCP2.cmake b/CMake/FindNGTCP2.cmake
index 37b060ea0d..61e54c2d67 100644
--- a/CMake/FindNGTCP2.cmake
+++ b/CMake/FindNGTCP2.cmake
@@ -71,7 +71,7 @@ endif()
 if(NGTCP2_FIND_COMPONENTS)
   set(NGTCP2_CRYPTO_BACKEND "")
   foreach(component IN LISTS NGTCP2_FIND_COMPONENTS)
-    if(component MATCHES "^(OpenSSL|GnuTLS)")
+    if(component MATCHES "^(BoringSSL|OpenSSL|GnuTLS)")
       if(NGTCP2_CRYPTO_BACKEND)
         message(FATAL_ERROR "NGTCP2: Only one crypto library can be selected")
       endif()
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5350e87985..5ecb944c7b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -451,6 +451,7 @@ if(CURL_USE_OPENSSL)
   check_symbol_exists(RAND_status "${CURL_INCLUDES}" HAVE_RAND_STATUS)
   check_symbol_exists(RAND_screen "${CURL_INCLUDES}" HAVE_RAND_SCREEN)
   check_symbol_exists(RAND_egd    "${CURL_INCLUDES}" HAVE_RAND_EGD)
+  check_symbol_exists(OPENSSL_IS_BORINGSSL "openssl/base.h" HAVE_BORINGSSL)
 
   add_definitions(-DOPENSSL_SUPPRESS_DEPRECATED)
 endif()
@@ -506,7 +507,7 @@ function(CheckQuicSupportInOpenSSL)
   set(CMAKE_REQUIRED_LIBRARIES  "${OPENSSL_LIBRARIES}")
   check_symbol_exists(SSL_CTX_set_quic_method "openssl/ssl.h" HAVE_SSL_CTX_SET_QUIC_METHOD)
   if(NOT HAVE_SSL_CTX_SET_QUIC_METHOD)
-    message(FATAL_ERROR "QUIC support is missing in OpenSSL/boringssl. Try setting -DOPENSSL_ROOT_DIR")
+    message(FATAL_ERROR "QUIC support is missing in OpenSSL/BoringSSL. Try setting -DOPENSSL_ROOT_DIR")
   endif()
   cmake_pop_check_state()
 endfunction()
@@ -514,7 +515,11 @@ endfunction()
 option(USE_NGTCP2 "Use ngtcp2 and nghttp3 libraries for HTTP/3 support" OFF)
 if(USE_NGTCP2)
   if(USE_OPENSSL)
-    find_package(NGTCP2 REQUIRED OpenSSL)
+    if(HAVE_BORINGSSL)
+      find_package(NGTCP2 REQUIRED BoringSSL)
+    else()
+      find_package(NGTCP2 REQUIRED OpenSSL)
+    endif()
     CheckQuicSupportInOpenSSL()
   elseif(USE_GNUTLS)
     # TODO add GnuTLS support as vtls library.