Add cross compilation support (#85)

Add support for cross-compiling curl-impersonate. Cross compiling can now be done using the '--host' flag to the configure script. This will make sure that all sub-components are cross-compiled. In addition, compiling for a different system requires explicitly specifying multiple paths used by curl (e.g. for certificates). These options were added to the configure script as well. The build and test CI workflow will now attempt to cross-compile curl-impersonate to ARM64 (aarch64), and upload this binary to the GitHub release page. Add the 'configure' script generated by autoconf and its dependencies to the repository to save the users from having to run 'autoconf' manually.
lwthiker · Jul 14, 2022 · 72f30c9 · 72f30c9
1 parent 6572db8
commit 72f30c9
Show file tree

Hide file tree

Showing 8 changed files with 9,539 additions and 87 deletions.
diff --git a/.github/workflows/build-and-test-make.yml b/.github/workflows/build-and-test-make.yml
@@ -21,15 +21,23 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-20.04, macos-11]
+        arch: [x86_64]
         include:
           - os: ubuntu-20.04
+            arch: x86_64
+            host: x86_64-linux-gnu
+            capture_interface: eth0
+            make: make
+          - os: ubuntu-20.04
+            arch: aarch64
+            host: aarch64-linux-gnu
             capture_interface: eth0
             make: make
-            release_name: x86_64-linux-gnu
           - os: macos-11
+            arch: x86_64
+            host: x86_64-macos
             capture_interface: en0
             make: gmake
-            release_name: x86_64-macos
     steps:
       - uses: actions/setup-python@v3
 
@@ -45,6 +53,11 @@ jobs:
           # More dependencies for the tests
           sudo apt-get install tcpdump nghttp2-server libnss3
 
+      - name: Install Ubuntu dependencies (aarch64)
+        if: matrix.arch == 'aarch64'
+        run: |
+          sudo apt-get install gcc-aarch64-linux-gnu g++-aarch64-linux-gnu
+
       - name: Install macOS dependencies
         if: matrix.os == 'macos-11'
         run: |
@@ -69,12 +82,38 @@ jobs:
         run: |
           pip3 install -r tests/requirements.txt
 
+      # When cross compiling we need to build zlib first.
+      - name: Build zlib
+        run: |
+          curl -LO https://zlib.net/zlib-1.2.12.tar.gz
+          tar xf zlib-1.2.12.tar.gz
+          cd zlib-1.2.12
+          CHOST=${{ matrix.host }} ./configure --prefix=${{ runner.temp }}/zlib
+          make
+          make install
+          # Make sure curl will link with libz.so.1 and not libz.so
+          rm -f ${{ runner.temp }}/zlib/lib/libz.so
+
       - name: Run configure script
+        if: matrix.arch == 'x86_64'
         run: |
-          autoconf
           mkdir ${{ runner.temp }}/install
           ./configure --prefix=${{ runner.temp }}/install
 
+      # When cross compiling a more complicated configuration is needed, since
+      # curl's configure script can't figure out where some files and libraries
+      # are located. The locations used here are the ones used by Ubuntu.
+      - name: Run configure script (cross compiling)
+        if: matrix.arch != 'x86_64'
+        run: |
+          mkdir ${{ runner.temp }}/install
+          ./configure --prefix=${{ runner.temp }}/install \
+                      --host=${{ matrix.host }} \
+                      --with-zlib=${{ runner.temp }}/zlib \
+                      --with-ca-path=/etc/ssl/certs \
+                      --with-ca-bundle=/etc/ssl/certs/ca-certificates.crt \
+                      --with-libnssckbi=/usr/lib/${{ matrix.host }}/nss
+
       # Cache the build of BoringSSL, which is the longest part of the build
       # We must cache the .zip as well, otherwise the Makefile will
       # rebuild BoringSSL. This whole thing is a bit hacky, but necessary to
@@ -83,14 +122,14 @@ jobs:
         uses: actions/cache@v3
         with:
           path: boringssl.zip
-          key: ${{ runner.os }}-boring-source-${{ env.BORING_SSL_COMMIT }}
+          key: ${{ runner.os }}-${{ matrix.arch }}-boring-source-${{ env.BORING_SSL_COMMIT }}
 
       - name: Cache BoringSSL build
         id: cache-boringssl
         uses: actions/cache@v3
         with:
           path: boringssl/build
-          key: ${{ runner.os }}-boring-build-${{ env.BORING_SSL_COMMIT }}-${{ hashFiles('chrome/patches/boringssl*.patch') }}
+          key: ${{ runner.os }}-${{ matrix.arch }}-boring-build-${{ env.BORING_SSL_COMMIT }}-${{ hashFiles('chrome/patches/boringssl*.patch') }}
 
       # Trick the Makefile into skipping the BoringSSL build step
       # if it was found in the cache. See Makefile.in
@@ -114,14 +153,14 @@ jobs:
         uses: actions/cache@v3
         with:
           path: ${{ env.NSS_VERSION }}.tar.gz
-          key: ${{ runner.os }}-nss-source-${{ env.NSS_VERSION }}
+          key: ${{ runner.os }}-${{ matrix.arch }}-nss-source-${{ env.NSS_VERSION }}
 
       - name: Cache NSS build
         id: cache-nss
         uses: actions/cache@v3
         with:
           path: ${{ env.NSS_VERSION }}/dist
-          key: ${{ runner.os }}-nss-build-${{ env.NSS_VERSION }}
+          key: ${{ runner.os }}-${{ matrix.arch }}-nss-build-${{ env.NSS_VERSION }}
 
       # Trick the Makefile into skipping the NSS build step
       # if it was found in the cache.
@@ -138,11 +177,15 @@ jobs:
           ${{ matrix.make }} firefox-install
     
       - name: Prepare the tests
+        if: matrix.arch == 'x86_64'
         run: |
           # Compile 'minicurl' which is used by the tests
           gcc -Wall -Werror -o ${{ runner.temp }}/install/bin/minicurl tests/minicurl.c `curl-config --libs`
 
+      # For now we can only run the tests when not cross compiling, since the
+      # tests run the curl-impersonate binary locally.
       - name: Run the tests
+        if: matrix.arch == 'x86_64'
         run: |
           cd tests
           # sudo is needed for capturing packets
@@ -154,18 +197,37 @@ jobs:
         if: startsWith(github.ref, 'refs/tags/')
         run: |
             cd ${{ runner.temp }}/install/lib
-            tar -c -z -f ${{ runner.temp }}/libcurl-impersonate-${{ github.ref_name }}.${{ matrix.release_name }}.tar.gz libcurl-impersonate*
-            echo "release_file_lib=${{ runner.temp }}/libcurl-impersonate-${{ github.ref_name }}.${{ matrix.release_name }}.tar.gz" >> $GITHUB_ENV
+            tar -c -z -f ${{ runner.temp }}/libcurl-impersonate-${{ github.ref_name }}.${{ matrix.host }}.tar.gz libcurl-impersonate*
+            echo "release_file_lib=${{ runner.temp }}/libcurl-impersonate-${{ github.ref_name }}.${{ matrix.host }}.tar.gz" >> $GITHUB_ENV
 
-       # Recompile curl-impersonate statically.
-      - name: Recompile statically
+      - name: Clean build
         if: startsWith(github.ref, 'refs/tags/')
         run: |
           ${{ matrix.make }} chrome-clean
           ${{ matrix.make }} firefox-clean
           rm -Rf ${{ runner.temp }}/install
           mkdir ${{ runner.temp }}/install
+
+       # Recompile curl-impersonate statically when doing a release.
+      - name: Reconfigure statically
+        if: startsWith(github.ref, 'refs/tags/') && matrix.arch == 'x86_64'
+        run: |
           ./configure --prefix=${{ runner.temp }}/install --enable-static
+
+      - name: Reconfigure statically (cross compiling)
+        if: startsWith(github.ref, 'refs/tags/') && matrix.arch != 'x86_64'
+        run: |
+          ./configure --prefix=${{ runner.temp }}/install \
+                      --enable-static \
+                      --host=${{ matrix.host }} \
+                      --with-zlib=${{ runner.temp }}/zlib \
+                      --with-ca-path=/etc/ssl/certs \
+                      --with-ca-bundle=/etc/ssl/certs/ca-certificates.crt \
+                      --with-libnssckbi=/usr/lib/${{ matrix.host }}/nss
+
+      - name: Rebuild statically
+        if: startsWith(github.ref, 'refs/tags/')
+        run: |
           ${{ matrix.make }} chrome-build
           ${{ matrix.make }} chrome-checkbuild
           ${{ matrix.make }} chrome-install-strip
@@ -177,8 +239,8 @@ jobs:
         if: startsWith(github.ref, 'refs/tags/')
         run: |
           cd ${{ runner.temp }}/install/bin
-          tar -c -z -f ${{ runner.temp }}/curl-impersonate-${{ github.ref_name }}.${{ matrix.release_name }}.tar.gz curl-impersonate-ff curl-impersonate-chrome curl_*
-          echo "release_file_bin=${{ runner.temp }}/curl-impersonate-${{ github.ref_name }}.${{ matrix.release_name }}.tar.gz" >> $GITHUB_ENV
+          tar -c -z -f ${{ runner.temp }}/curl-impersonate-${{ github.ref_name }}.${{ matrix.host }}.tar.gz curl-impersonate-ff curl-impersonate-chrome curl_*
+          echo "release_file_bin=${{ runner.temp }}/curl-impersonate-${{ github.ref_name }}.${{ matrix.host }}.tar.gz" >> $GITHUB_ENV
 
       - name: Upload release files
         uses: softprops/action-gh-release@v1

diff --git a/INSTALL.md b/INSTALL.md
@@ -2,9 +2,10 @@
 
 This guide shows how to compile and install curl-impersonate and libcurl-impersonate from source.
 The build process takes care of downloading dependencies, patching them, compiling them and finally compiling curl itself with the needed patches.
-There are currently two build options depending on your use case:
-* Native build using Makefile
-* Docker container build
+There are currently three build options depending on your use case:
+* [Native build](#Native-build) using an autotools-based Makefile
+* [Cross compiling](#Cross-compiling) using an autotools-based Makefile
+* [Docker container build](#Docker-build)
 
 There are two versions of `curl-impersonate` for technical reasons. The **chrome** version is used to impersonate Chrome, Edge and Safari. The **firefox** version is used to impersonate Firefox.
 
@@ -29,11 +30,6 @@ git clone https://github.com/lwthiker/curl-impersonate.git
 cd curl-impersonate
 ```
 
-Generate the configure script:
-```
-autoconf
-```
-
 Configure and compile:
 ```
 mkdir build && cd build
@@ -102,11 +98,6 @@ pip3 install gyp-next
 brew install go
 ```
 
-Generate the configure script:
-```
-autoconf
-```
-
 Configure and compile:
 ```
 mkdir build && cd build
@@ -135,6 +126,32 @@ Make sure that NSS is installed (see above).
 If the issue persists it might be that NSS is installed in a non-standard location on your system.
 Please open an issue in that case.
 
+## Cross compiling
+
+There is some basic support for cross compiling curl-impersonate.
+It is currently being used to build curl-impersonate for ARM64 (aarch64) systems from x86-64 systems.
+Cross compiling is similar to the usual build but a bit trickier:
+* You'd have to build zlib for the target architecture so that curl can link with it.
+* Some paths have to be specified manually since curl's own build system can't determine their location.
+
+An example build for aarch64 on Ubuntu x86_64:
+```
+sudo apt-get install gcc-aarch64-linux-gnu g++-aarch64-linux-gnu
+
+./configure --host=aarch64-linux-gnu \
+            --with-zlib=/path/to/compiled/zlib \
+            --with-ca-path=/etc/ssl/certs \
+            --with-ca-bundle=/etc/ssl/certs/ca-certificates.crt \
+            --with-libnssckbi=/usr/lib/aarch64-linux-gnu/nss
+
+make chrome-build
+make firefox-build
+```
+The flags mean as follows:
+`--with-zlib` is the location of a compiled zlib library for the target architecture.
+`--with-ca-path` and `--with-ca-bundle` will be passed to curl's configure script as is.
+`--with-libnssckbi` indicates the location of libnssckbi.so on the target system. This file contains the certificates needed by curl. This must be supplied if NSS is not installed in a standard location (i.e. not in `/usr/lib`).
+
 ## Docker build
 The Docker build is a bit more reproducible and serves as the reference implementation. It creates a Debian-based Docker image with the binaries.