ci: add azure ip masq merger to pipeline

.pipelines/build/dockerfiles/azure-ip-masq-merger.Dockerfile

@@ -0,0 +1,7 @@
+ARG ARCH
+
+FROM scratch AS linux
+ARG ARTIFACT_DIR
+
+COPY ${ARTIFACT_DIR}/bin/azure-ip-masq-merger /azure-ip-masq-merger
+ENTRYPOINT ["/azure-ip-masq-merger"]

.pipelines/build/ob-prepare.steps.yaml

@@ -1,4 +1,3 @@
-
 steps:
 - template: utils/rename-dockerfile-references.steps.yaml
   parameters:
@@ -59,6 +58,10 @@ steps:
     echo "##vso[task.setvariable variable=azureIpamVersion;isOutput=true]$AZUREIPAMVERSION"
     echo "azureIpamVersion: $AZUREIPAMVERSION"
 
+    AZUREIPMASQMERGERVERSION=$(make azure-ip-masq-merger-version)
+    echo "##vso[task.setvariable variable=azureIpMasqMergerVersion;isOutput=true]$AZUREIPMASQMERGERVERSION"
+    echo "azureIpMasqMergerVersion: $AZUREIPMASQMERGERVERSION"
+
     CNIVERSION=$(make cni-version)
     echo "##vso[task.setvariable variable=cniVersion;isOutput=true]$CNIVERSION"
     echo "cniVersion: $CNIVERSION"

.pipelines/build/scripts/azure-ip-masq-merger.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+set -eux
+
+[[ $OS =~ windows ]] && { echo "azure-ip-masq-merger is not supported on Windows"; exit 1; }
+FILE_EXT=''
+
+export CGO_ENABLED=0 
+
+mkdir -p "$OUT_DIR"/bin
+mkdir -p "$OUT_DIR"/files
+
+pushd "$REPO_ROOT"/azure-ip-masq-merger
+  GOOS="$OS" go build -v -a -trimpath \
+    -o "$OUT_DIR"/bin/azure-ip-masq-merger"$FILE_EXT" \
+    -ldflags "-X github.com/Azure/azure-container-networking/azure-ip-masq-merger/internal/buildinfo.Version=$AZURE_IP_MASQ_MERGER_VERSION -X main.version=$AZURE_IP_MASQ_MERGER_VERSION" \
+    -gcflags="-dwarflocationlists=true" \
+    .
+popd

.pipelines/pipeline.yaml

@@ -121,6 +121,10 @@ stages:
                 arch: amd64
                 name: azure-ipam
                 os: windows
+              azure_ip_masq_merger_linux_amd64:
+                arch: amd64
+                name: azure-ip-masq-merger
+                os: linux
               cni_linux_amd64:
                 arch: amd64
                 name: cni
@@ -166,6 +170,10 @@ stages:
                 arch: arm64
                 name: azure-ipam
                 os: linux
+              azure_ip_masq_merger_linux_arm64:
+                arch: arm64
+                name: azure-ip-masq-merger
+                os: linux
               cni_linux_arm64:
                 arch: arm64
                 name: cni
@@ -217,6 +225,9 @@ stages:
               npm:
                 name: npm
                 platforms: linux/amd64 linux/arm64 windows/amd64
+              azure_ip_masq_merger:
+                name: azure-ip-masq-merger
+                platforms: linux/amd64 linux/arm64
           steps:
             - template: containers/manifest-template.yaml
               parameters:

.pipelines/run-pipeline.yaml

@@ -39,6 +39,7 @@ stages:
 
       IMAGE_REPO_PATH: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.imageRepositoryPath'] ]
       AZURE_IPAM_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.azureIpamVersion'] ]
+      AZURE_IP_MASQ_MERGER_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.azureIpMasqMergerVersion'] ]
       CNI_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.cniVersion'] ]
       CNS_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.cnsVersion'] ]
       IPV6_HP_BPF_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.ipv6HpBpfVersion'] ]
@@ -63,6 +64,12 @@ stages:
                 archiveVersion: $(AZURE_IPAM_VERSION)
                 imageTag: $(Build.BuildNumber)
                 packageWithDropGZ: True
+              azure_ip_masq_merger:
+                name: azure-ip-masq-merger
+                extraArgs: ''
+                archiveName: azure-ip-masq-merger
+                archiveVersion: $(AZURE_IP_MASQ_MERGER_VERSION)
+                imageTag: $(Build.BuildNumber)
               cni:
                 name: cni
                 extraArgs: '--build-arg CNI_AI_PATH=$(CNI_AI_PATH) --build-arg CNI_AI_ID=$(CNI_AI_ID)'
@@ -141,6 +148,12 @@ stages:
                 extraArgs: ''
                 imageTag: $(Build.BuildNumber)
                 packageWithDropGZ: True
+              azure_ip_masq_merger:
+                name: azure-ip-masq-merger
+                extraArgs: ''
+                archiveName: azure-ip-masq-merger
+                archiveVersion: $(AZURE_IP_MASQ_MERGER_VERSION)
+                imageTag: $(Build.BuildNumber)
               cni:
                 name: cni
                 extraArgs: '--build-arg CNI_AI_PATH=$(CNI_AI_PATH) --build-arg CNI_AI_ID=$(CNI_AI_ID)'
@@ -177,6 +190,7 @@ stages:
       IMAGE_REPO_PATH: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.imageRepositoryPath'] ]
 
       AZURE_IPAM_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.azureIpamVersion'] ]
+      AZURE_IP_MASQ_MERGER_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.azureIpMasqMergerVersion'] ]
       CNI_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.cniVersion'] ]
       CNS_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.cnsVersion'] ]
       IPV6_HP_BPF_VERSION: $[ stageDependencies.setup.env.outputs['EnvironmentalVariables.ipv6HpBpfVersion'] ]
@@ -186,6 +200,9 @@ stages:
       IPAM_LINUX_ARM64_REF: $(IMAGE_REPO_PATH)/linux-arm64/azure-ipam:$(Build.BuildNumber)
       IPAM_WINDOWS_AMD64_REF: $(IMAGE_REPO_PATH)/windows-amd64/azure-ipam:$(Build.BuildNumber)
 
+      IP_MASQ_MERGER_LINUX_AMD64_REF: $(IMAGE_REPO_PATH)/linux-amd64/azure-ip-masq-merger:$(Build.BuildNumber)
+      IP_MASQ_MERGER_LINUX_ARM64_REF: $(IMAGE_REPO_PATH)/linux-arm64/azure-ip-masq-merger:$(Build.BuildNumber)
+
       CNI_LINUX_AMD64_REF: $(IMAGE_REPO_PATH)/linux-amd64/cni:$(Build.BuildNumber)
       CNI_LINUX_ARM64_REF: $(IMAGE_REPO_PATH)/linux-arm64/cni:$(Build.BuildNumber)
       CNI_WINDOWS_AMD64_REF: $(IMAGE_REPO_PATH)/windows-amd64/cni:$(Build.BuildNumber)
@@ -216,6 +233,15 @@ stages:
               imageReference: $(IPAM_LINUX_ARM64_REF)
             - platform: windows/amd64
               imageReference: $(IPAM_WINDOWS_AMD64_REF)
+        - job: azure_ip_masq_merger
+          templateContext:
+            name: azure-ip-masq-merger
+            image_tag: $(AZURE_IP_MASQ_MERGER_VERSION)
+            platforms:
+            - platform: linux/amd64
+              imageReference: $(IP_MASQ_MERGER_LINUX_AMD64_REF)
+            - platform: linux/arm64
+              imageReference: $(IP_MASQ_MERGER_LINUX_ARM64_REF)
         - job: cni
           templateContext:
             name: cni

azure-ip-masq-merger/Dockerfile

@@ -15,12 +15,6 @@ WORKDIR /azure-ip-masq-merger
 COPY ./azure-ip-masq-merger .
 RUN GOOS=$OS CGO_ENABLED=0 go build -a -o /go/bin/ip-masq-merger -trimpath -ldflags "-X main.version="$VERSION"" -gcflags="-dwarflocationlists=true" .
 
-# TODO: Replace with scratch later
-FROM --platform=linux/${ARCH} mcr.microsoft.com/azurelinux/base/core@sha256:b46476be0b5c9691ad20f78871819950c01433bdfad81d72c61618f4a6202b25 AS linux
-COPY --from=azure-ip-masq-merger /go/bin/ip-masq-merger ip-masq-merger
-ENTRYPOINT [ "/ip-masq-merger" ]
-
-# skopeo inspect docker://mcr.microsoft.com/oss/kubernetes/windows-host-process-containers-base-image:v1.0.0 --format "{{.Name}}@{{.Digest}}"
-FROM mcr.microsoft.com/oss/kubernetes/windows-host-process-containers-base-image@sha256:b4c9637e032f667c52d1eccfa31ad8c63f1b035e8639f3f48a510536bf34032b as windows
-COPY --from=azure-ip-masq-merger /go/bin/ip-masq-merger ip-masq-merger.exe
-ENTRYPOINT [ "/ip-masq-merger.exe" ]
+FROM scratch AS linux
+COPY --from=azure-ip-masq-merger /go/bin/ip-masq-merger azure-ip-masq-merger
+ENTRYPOINT [ "/azure-ip-masq-merger" ]

azure-ip-masq-merger/README.md

@@ -0,0 +1,69 @@
+# azure-ip-masq-merger
+
+`azure-ip-masq-merger` is a utility for merging multiple ip-masq-agent configuration files into a single, valid configuration for use in Kubernetes clusters.
+
+## Description
+
+The goal of this program is to periodically scan a directory for configuration fragments (YAML or JSON files starting with `ip-masq`), validate and merge them, and write the resulting configuration to a target directory for consumption. This allows us to combine non-masquerade CIDRs and related options between multiple files, for example if we had one ip masq config managed by the cloud provider and another supplied by the user.
+
+## Usage
+
+Follow the steps below to build and run the program:
+
+1. Build the binary using `make`:
+    ```bash
+    make azure-ip-masq-merger
+    ```
+    or make an image:
+    ```bash
+    make azure-ip-masq-merger-image
+    ```
+
+2. Deploy or copy the binary to your node(s).
+
+3. Prepare your configuration fragments in the input directory (see below for defaults). Each file should be named with the prefix `ip-masq` and contain valid YAML or JSON for the ip-masq-agent config.
+
+4. Start the program with:
+    ```bash
+    ./azure-ip-masq-merger --input=/etc/config/ --output=/etc/merged-config/
+    ```
+    - The `--input` flag specifies the directory to scan for config fragments. Default: `/etc/config/`
+    - The `--output` flag specifies where to write the merged config. Default: `/etc/merged-config/`
+
+5. The merged configuration will be written to the output directory as `ip-masq-agent`. If no valid configs are found, any existing merged config will be removed.
+
+## Manual Testing
+
+You can test the merger locally by creating sample config files in your input directory and running the merger.
+
+## Configuration File Format
+
+Each config fragment should be a YAML or JSON file that may have the following fields:
+```yaml
+nonMasqueradeCIDRs:
+  - 10.0.0.0/8
+  - 192.168.0.0/16
+masqLinkLocal: true
+masqLinkLocalIPv6: false
+```
+- `nonMasqueradeCIDRs`: List of CIDRs that should not be masqueraded. Appended between configs.
+- `masqLinkLocal`: Boolean to enable/disable masquerading of link-local addresses. OR'd between configs.
+- `masqLinkLocalIPv6`: Boolean to enable/disable masquerading of IPv6 link-local addresses. OR'd between configs.
+
+## Debugging
+
+Logs are output to standard error. Increase verbosity with the `-v` flag:
+```bash
+./azure-ip-masq-merger -v 2
+```
+
+## Development
+
+To run tests:
+```bash
+go test ./...
+```
+or at the repository level:
+```bash
+make test-azure-ip-masq-merger
+```