Allow the user to build oqs-provider as a static library.

This commit removes the `SHARED` argument of the `add_library`.
By doing so, we let the user choose the build type of library.

By default, CMake will build a static library. Thus, [`BUILD_SHARED_LIBS`]
must be used to switch to a shared library.

`oqs-provider` as a static library allows us to use the provider without
having to store its shared library somewhere. In addition, it happens that
some operating systems prohibit the use of `dlopen`/`dlsym`.

To load `oqs-provider` when it is embedded into a library of a binary, one
can use the [`OSSL_PROVIDER_add_builtin`] API from OpenSSL 3.

[`BUILD_SHARED_LIBS`]: https://cmake.org/cmake/help/latest/variable/BUILD_SHARED_LIBS.html
[`OSSL_PROVIDER_add_builtin`]: https://www.openssl.org/docs/man3.1/man3/OSSL_PROVIDER_add_builtin.html

.circleci/config.yml

@@ -46,7 +46,7 @@ jobs:
               equal: [ openssl@3, << parameters.OPENSSL_PREINSTALL >> ]
           steps:
             - run:
-                name: Clone and build OpenSSL(3) 
+                name: Clone and build OpenSSL(3)
                 command: |
                    git clone --branch master git://git.openssl.org/openssl.git openssl &&
                    cd openssl && ./config --prefix=$(echo $(pwd)/../.local) && make -j 18 && make install_sw && cd ..
@@ -69,11 +69,11 @@ jobs:
       - run:
           name: Run tests (with encodings, positive and negative test)
           command: |
-            ./scripts/runtests_encodings.sh -V > log 
-            if [ grep "Skipping testing of buggy OpenSSL" -eq 1 ]; then 
+            ./scripts/runtests_encodings.sh -V > log
+            if [ grep "Skipping testing of buggy OpenSSL" -eq 1 ]; then
                cat log
                ! OQS_ENCODING_DILITHIUM2=foo OQS_ENCODING_DILITHIUM2_ALGNAME=bar ./scripts/runtests.sh -V
-            else 
+            else
                cat log
             fi
       - run:
@@ -88,10 +88,10 @@ jobs:
           name: Run tests (-DNOPUBKEY_IN_PRIVKEY=ON, with encodings, positive and negative test)
           command: |
             ./scripts/runtests_encodings.sh -V
-            if [ grep "Skipping testing of buggy OpenSSL" -eq 1 ]; then 
+            if [ grep "Skipping testing of buggy OpenSSL" -eq 1 ]; then
                cat log
                ! OQS_ENCODING_DILITHIUM2=foo OQS_ENCODING_DILITHIUM2_ALGNAME=bar ./scripts/runtests.sh -V
-            else 
+            else
                cat log
             fi
 
@@ -120,7 +120,7 @@ jobs:
              git clone --depth 1 --branch main https://github.com/open-quantum-safe/liboqs.git &&
              export LIBOQS_INSTALLPATH=$(pwd)/.local && cd liboqs && mkdir _build && cd _build &&
              cmake -GNinja -DCMAKE_INSTALL_PREFIX=$LIBOQS_INSTALLPATH << parameters.CMAKE_ARGS >> .. && ninja install &&
-             cd .. && cd .. && echo "export DYLD_LIBRARY_PATH=$DYLD_LIBRARY_PATH:$LIBOQS_INSTALLPATH/lib" >> "$BASH_ENV" 
+             cd .. && cd .. && echo "export DYLD_LIBRARY_PATH=$DYLD_LIBRARY_PATH:$LIBOQS_INSTALLPATH/lib" >> "$BASH_ENV"
       - when:
           condition:
             not:
@@ -158,11 +158,11 @@ jobs:
       - run:
           name: Run tests (with encodings)
           command: |
-            ./scripts/runtests_encodings.sh -V > log 
-            if [ grep "Skipping testing of buggy OpenSSL" -eq 1 ]; then 
+            ./scripts/runtests_encodings.sh -V > log
+            if [ grep "Skipping testing of buggy OpenSSL" -eq 1 ]; then
                cat log
                ! OQS_ENCODING_DILITHIUM2=foo OQS_ENCODING_DILITHIUM2_ALGNAME=bar ./scripts/runtests.sh -V
-            else 
+            else
                cat log
             fi
 
@@ -194,21 +194,21 @@ workflows:
           name: ubuntu-focal
           context: openquantumsafe
           IMAGE: openquantumsafe/ci-ubuntu-focal-x86_64:latest
-          CMAKE_ARGS: -DOQS_STRICT_WARNINGS=ON -DOQS_USE_OPENSSL=OFF
+          CMAKE_ARGS: -DOQS_STRICT_WARNINGS=ON -DOQS_USE_OPENSSL=OFF -DBUILD_SHARED_LIBS=ON
           OPENSSL_PREINSTALL: openssl@1
       - ubuntu:
           name: ubuntu-jammy
           context: openquantumsafe
           IMAGE: openquantumsafe/ci-ubuntu-jammy:latest
-          CMAKE_ARGS: -DOQS_STRICT_WARNINGS=ON -DOQS_ALGS_ENABLED=STD
+          CMAKE_ARGS: -DOQS_STRICT_WARNINGS=ON -DOQS_ALGS_ENABLED=STD -DBUILD_SHARED_LIBS=ON
           OPENSSL_PREINSTALL: openssl@3
       - macOS:
           name: macOS-noopenssl
-          CMAKE_ARGS: -DOQS_STRICT_WARNINGS=ON -DOQS_USE_OPENSSL=OFF
+          CMAKE_ARGS: -DOQS_STRICT_WARNINGS=ON -DOQS_USE_OPENSSL=OFF -DBUILD_SHARED_LIBS=ON
           OPENSSL_PREINSTALL: openssl
       - macOS:
           name: macOS-shared
-          CMAKE_ARGS: -DBUILD_SHARED_LIBS=ON -DOQS_DIST_BUILD=OFF -DOQS_ENABLE_KEM_CLASSIC_MCELIECE=OFF
+          CMAKE_ARGS: -DOQS_DIST_BUILD=OFF -DOQS_ENABLE_KEM_CLASSIC_MCELIECE=OFF -DBUILD_SHARED_LIBS=ON
           OPENSSL_PREINSTALL: openssl@3
   on-main-branch:
     when:

.github/workflows/windows.yml

@@ -68,7 +68,7 @@ jobs:
         if: steps.cache-openssl32.outputs.cache-hit != 'true'
         run: bash -c "./config --prefix=/opt/openssl32 ${{ matrix.platform.config }} && perl configdata.pm --dump && make $MAKE_PARAMS && make install_sw"
         working-directory: openssl
-      - name: Check OpenSSL install3 
+      - name: Check OpenSSL install3
         run: dir c:\cygwin\opt\openssl32
       - name: Save OpenSSL
         id: cache-openssl-save
@@ -79,7 +79,7 @@ jobs:
             c:\cygwin\opt\openssl32
           key: ${{ runner.os }}-cygwinopenssl32
       - name: build oqs-provider
-        run: bash -c "git config --global --add safe.directory $(cygpath -u $PWD) && liboqs_DIR='${{ env.IP }}' cmake -GNinja -DCMAKE_C_COMPILER=gcc -DOPENSSL_ROOT_DIR=/opt/openssl32 -S . -B _build && cd _build && ninja && cd .."
+        run: bash -c "git config --global --add safe.directory $(cygpath -u $PWD) && liboqs_DIR='${{ env.IP }}' cmake -GNinja -DBUILD_SHARED_LIBS=ON -DCMAKE_C_COMPILER=gcc -DOPENSSL_ROOT_DIR=/opt/openssl32 -S . -B _build && cd _build && ninja && cd .."
       - name: Adapt oqsprovider.dll name
         run: bash -c "cp oqsprovider-1.dll oqsprovider.dll"
         working-directory: _build/bin
@@ -190,7 +190,7 @@ jobs:
           key: ${{ runner.os }}-msvcopenssl32
       - name: build oqs-provider
         run: |
-          cmake -GNinja -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_FLAGS="/wd5105" -DOPENSSL_ROOT_DIR="c:\openssl32" -Dliboqs_DIR="c:\liboqs\lib\cmake\liboqs" -S . -B _build
+          cmake -GNinja -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_FLAGS="/wd5105" -DBUILD_SHARED_LIBS=ON -DOPENSSL_ROOT_DIR="c:\openssl32" -Dliboqs_DIR="c:\liboqs\lib\cmake\liboqs" -S . -B _build
           cd _build
           ninja
       - name: Run tests

oqsprov/CMakeLists.txt

@@ -31,7 +31,7 @@ set(PROVIDER_SOURCE_FILES
 set(PROVIDER_HEADER_FILES
   oqs_prov.h oqs_endecoder_local.h
 )
-add_library(oqsprovider SHARED ${PROVIDER_SOURCE_FILES})
+add_library(oqsprovider ${PROVIDER_SOURCE_FILES})
 if (USE_ENCODING_LIB)
   add_dependencies(oqsprovider encoder)
 endif()

scripts/fullbuild.sh

@@ -107,9 +107,9 @@ if [ ! -f "_build/lib/oqsprovider.$SHLIBEXT" ]; then
    BUILD_TYPE=""
    # for omitting public key in private keys add -DNOPUBKEY_IN_PRIVKEY=ON
    if [ -z "$OPENSSL_INSTALL" ]; then
-       cmake -DOPENSSL_ROOT_DIR=$(pwd)/.local $BUILD_TYPE -S . -B _build && cmake --build _build
+       cmake -DOPENSSL_ROOT_DIR=$(pwd)/.local $BUILD_TYPE -S . -B _build -DBUILD_SHARED_LIBS=ON && cmake --build _build
    else
-       cmake -DOPENSSL_ROOT_DIR=$OPENSSL_INSTALL $BUILD_TYPE -S . -B _build && cmake --build _build
+       cmake -DOPENSSL_ROOT_DIR=$OPENSSL_INSTALL $BUILD_TYPE -S . -B _build -DBUILD_SHARED_LIBS=ON && cmake --build _build
    fi
    if [ $? -ne 0 ]; then
      echo "provider build failed. Exiting."