build: integrate bottlerocket-license-tool

Add support for the `Licenses.toml` file, used to provide licensing
information for some packages.
When the `Licenses.toml` file and the `licenses` folder are provided,
they are copied to the build directory of the package. If either path is
missing, empty configurations are provided. When this happens, packages
that use `Licenses.toml` will fail to build.

Signed-off-by: Arnaldo Garcia Rincon <[email protected]>

.gitignore

@@ -9,3 +9,5 @@
 /*.pem
 /keys
 /roles
+/Licenses.toml
+/licenses

BUILDING.md

@@ -92,6 +92,35 @@ cargo make -e BUILDSYS_ARCH=my-arch-here
 
 (You can use variant and arch arguments together, too.)
 
+#### Package licenses
+
+Most packages will include license files extracted from upstream source archives.
+However, in some rare cases there are multiple licenses that could apply to a package.
+Bottlerocket's build system uses the `Licenses.toml` file in conjuction with the `licenses` directory to configure the licenses used for such special packages.
+Here is an example of a simple `Licenses.toml` configuration file:
+
+```toml
+[package]
+spdx-id = "SPDX-ID"
+licenses = [
+  { path = "the-license.txt" }
+]
+```
+
+In the previous example, it is expected that the file `the-license.txt` is present in `licenses`.
+You can retrieve the licenses from a remote endpoint, or the local filesystem if you specify the `license-url` field:
+
+```toml
+[package]
+spdx-id = "SPDX-ID AND SPDX-ID-2" # Package with multiple licenses
+licenses = [
+  # This file is copied from a file system, and will be saved as `path`
+  { license-url = "file:///path/to/spdx-id-license.txt", path = "spdx-id-license.txt" },
+  # This file is fetched from an https endpoint, and will be saved as `path`
+  { license-url = "https://localhost/spdx-id-license-v2.txt", path = "spdx-id-license-2.txt" }
+]
+```
+
 ### Register an AMI
 
 To use the image in Amazon EC2, we need to register the image as an AMI.

Dockerfile

@@ -68,6 +68,16 @@ WORKDIR /home/builder
 USER builder
 ENV PACKAGE=${PACKAGE} ARCH=${ARCH}
 COPY --chown=builder roles/${REPO}.root.json ./rpmbuild/BUILD/root.json
+# We attempt to copy `Licenses.toml` and `licenses` for the current build, otherwise
+# an empty file and a directory are created so that `bottlerocket-license-tool` will
+# fail with a more descriptive error message.
+RUN --mount=target=/host \
+  ( [ -f /host/Licenses.toml ] \
+  && cp /host/Licenses.toml ./rpmbuild/BUILD/ \
+  || touch ./rpmbuild/BUILD/Licenses.toml ) \
+  && ( [ -d /host/licenses ] \
+  && cp -r /host/licenses ./rpmbuild/BUILD/ \
+  || mkdir ./rpmbuild/BUILD/licenses )
 COPY ./macros/${ARCH} ./macros/shared ./macros/rust ./macros/cargo ./packages/${PACKAGE}/ .
 RUN rpmdev-setuptree \
    && cat ${ARCH} shared rust cargo > .rpmmacros \

Makefile.toml

@@ -57,6 +57,10 @@ PUBLISH_UNIFIED_VOLUME_SIZE = "22"
 # tools/pubsys/policies/ssm/README.md for more information.
 PUBLISH_SSM_TEMPLATES_PATH = "${BUILDSYS_ROOT_DIR}/tools/pubsys/policies/ssm/defaults.toml"
 
+# This can be overriden with -e to change the source path
+# for the Licenses.toml file
+BUILDSYS_LICENSES_CONFIG_PATH = "${BUILDSYS_ROOT_DIR}/Licenses.toml"
+
 # Specifies whether to validate all targets when validating TUF repositories
 REPO_VALIDATE_TARGETS = "true"
 # Specifies the timeframe to look for upcoming repository metadata expirations
@@ -89,6 +93,10 @@ BUILDSYS_UPSTREAM_SOURCE_FALLBACK = "false"
 # if the license check fails.
 BUILDSYS_ALLOW_FAILED_LICENSE_CHECK = "false"
 
+# Disallow pulling licenses from Upstream URLs. To fetch licenses from the upstream source,
+# override this on the command line and set it to 'true'
+BUILDSYS_UPSTREAM_LICENSE_FETCH= "false"
+
 # This controls how many `docker build` commands we'll invoke at once.
 BUILDSYS_JOBS = "8"
 
@@ -391,7 +399,7 @@ fi
 
 # Builds a package including its build-time and runtime dependency packages.
 [tasks.build-package]
-dependencies = ["check-cargo-version", "build-tools", "publish-setup"]
+dependencies = ["check-cargo-version", "build-tools", "publish-setup", "fetch-licenses"]
 script_runner = "bash"
 script = [
 '''
@@ -605,6 +613,44 @@ docker run --rm \
 '''
 ]
 
+[tasks.fetch-licenses]
+dependencies = ["fetch"]
+script = [
+'''
+if [ "${BUILDSYS_UPSTREAM_LICENSE_FETCH}" = "false" ]; then
+  echo "Skipping fetching licenses"
+  exit 0
+fi
+
+# Attempt copy Licenses.toml
+cp "${BUILDSYS_LICENSES_CONFIG_PATH}" "${BUILDSYS_ROOT_DIR}/Licenses.toml" 2>/dev/null \
+  || echo "Skipping copying file from ${BUILDSYS_LICENSES_CONFIG_PATH}"
+
+if [ ! -s "${BUILDSYS_ROOT_DIR}"/Licenses.toml ] ; then
+  echo "Not fetching licenses since 'Licenses.toml' doesn't exist"
+  exit 0
+fi
+
+mkdir -p "${BUILDSYS_ROOT_DIR}"/licenses
+
+run_fetch_licenses="
+bottlerocket-license-tool -l /tmp/Licenses.toml fetch /tmp/licenses
+"
+set +e
+
+docker run --rm \
+  --user "$(id -u):$(id -g)" \
+  --security-opt label:disable \
+  -e CARGO_HOME="/tmp/.cargo" \
+  -v "${CARGO_HOME}":/tmp/.cargo \
+  -v "${BUILDSYS_ROOT_DIR}/licenses:/tmp/licenses" \
+  -v "${BUILDSYS_ROOT_DIR}/Licenses.toml:/tmp/Licenses.toml" \
+  "${BUILDSYS_SDK_IMAGE}" \
+  bash -c "${run_fetch_licenses}"
+'''
+]
+
+
 [tasks.link-clean]
 dependencies = ["fetch"]
 script = [
@@ -642,6 +688,7 @@ fi
 dependencies = [
     "link-clean",
     "check-licenses",
+    "fetch-licenses",
     "build-variant",
     "build-ova",
     "link-variant",