Patch to unbundle dependencies to build in Gentoo.

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 96d509739..1b214f5a6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -337,6 +337,10 @@ endif ()
 find_package (OpenSSL REQUIRED)
 set (INCLUDE_DIRECTORIES ${INCLUDE_DIRECTORIES} ${OPENSSL_INCLUDE_DIR})

+set(Libcrypto_LIBRARIES OpenSSL::Crypto)
+set(Libcrypto_INCLUDE_DIRS ${OPENSSL_INCLUDE_DIR})
+add_definitions(-DLIBRESSL_VERSION_NUMBER=1)
+
 find_package (Libcrypto REQUIRED)
 # We do not add the Libcrypto include directories to INCLUDE_DIRECTORIES
 # to avoid a clash with the system openssl. We only use it for libcvmfs_crypto
--

--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -343,7 +343,7 @@ set (INCLUDE_DIRECTORIES ${INCLUDE_DIRECTORIES} ${GTEST_INCLUDE_DIRS})
 find_package (GMock REQUIRED)
 set (INCLUDE_DIRECTORIES ${INCLUDE_DIRECTORIES} ${GMOCK_INCLUDE_DIRS})
 
-find_package (VJSON REQUIRED)
+add_subdirectory(externals/vjson)
 set (INCLUDE_DIRECTORIES ${INCLUDE_DIRECTORIES} ${VJSON_INCLUDE_DIRS})
 
 find_package (LibArchive REQUIRED)
diff --git a/externals/vjson/CMakeLists.txt b/externals/vjson/CMakeLists.txt
new file mode 100644
index 000000000..c1f82ce03
--- /dev/null
+++ b/externals/vjson/CMakeLists.txt
@@ -0,0 +1,8 @@
+project(VJSON)
+
+add_library(cvmfs_vjson STATIC src/block_allocator.cpp src/json.cpp)
+set_property(TARGET cvmfs_vjson PROPERTY POSITION_INDEPENDENT_CODE TRUE)
+target_include_directories(cvmfs_vjson PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/src)
+set(VJSON_INCLUDE_DIRS ${CMAKE_CURRENT_SOURCE_DIR}/src PARENT_SCOPE)
+set(VJSON_LIBRARY $<TARGET_FILE:cvmfs_vjson> PARENT_SCOPE)
+set(VJSON_LIBRARIES cvmfs_vjson PARENT_SCOPE)
-- 

--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -356,7 +356,7 @@ if (BUILD_CVMFS OR BUILD_LIBCVMFS OR BUILD_SERVER OR BUILD_SERVER_DEBUG OR
   find_package (ZLIB REQUIRED)
   set (INCLUDE_DIRECTORIES ${INCLUDE_DIRECTORIES} ${ZLIB_INCLUDE_DIRS})
 
-  find_package (SHA3 REQUIRED)
+  add_subdirectory(externals/sha3)
   set (INCLUDE_DIRECTORIES ${INCLUDE_DIRECTORIES} ${SHA3_INCLUDE_DIRS})
 endif ()
 
diff --git a/externals/sha3/CMakeLists.txt b/externals/sha3/CMakeLists.txt
new file mode 100644
index 000000000..7efa79b65
--- /dev/null
+++ b/externals/sha3/CMakeLists.txt
@@ -0,0 +1,19 @@
+project(SHA3)
+
+add_library(cvmfs_sha3 STATIC
+  src/64opt/KeccakF-1600-opt64.c
+  src/KeccakHash.c
+  src/KeccakSponge.c
+  src/SnP-FBWL-default.c
+)
+
+set_property(TARGET cvmfs_sha3 PROPERTY POSITION_INDEPENDENT_CODE TRUE)
+
+target_include_directories(cvmfs_sha3 PUBLIC
+  ${CMAKE_CURRENT_SOURCE_DIR}/src
+  ${CMAKE_CURRENT_SOURCE_DIR}/src/64opt
+)
+
+set(SHA3_INCLUDE_DIRS ${CMAKE_CURRENT_SOURCE_DIR}/src ${CMAKE_CURRENT_SOURCE_DIR}/src/64opt PARENT_SCOPE)
+set(SHA3_LIBRARY $<TARGET_FILE:cvmfs_sha3> PARENT_SCOPE)
+set(SHA3_LIBRARIES cvmfs_sha3 PARENT_SCOPE)
--