Update pipeline drone-docker-harness

* Add push-only support

* Include support for PLUGIN_NO_PUSH as well

.drone.yml

@@ -12,7 +12,7 @@ platform:
 
 steps:
   - name: vet
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - go vet ./...
     environment:
@@ -22,7 +22,7 @@ steps:
         path: /go
 
   - name: test
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - go test -cover ./...
     environment:
@@ -55,7 +55,7 @@ platform:
 
 steps:
   - name: go build
-    image: golang:1.22.4
+    image: golang:1.23
     environment:
       CGO_ENABLED: 0
     commands:
@@ -162,7 +162,7 @@ platform:
 
 steps:
   - name: go build
-    image: golang:1.22.4
+    image: golang:1.23
     environment:
       CGO_ENABLED: 0
     commands:
@@ -264,7 +264,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/amd64/drone-docker ./cmd/drone-docker'
     environment:
@@ -275,7 +275,7 @@ steps:
           - tag
 
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/amd64/drone-docker ./cmd/drone-docker'
     environment:
@@ -285,7 +285,7 @@ steps:
         - tag
 
   - name: executable
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - ./release/linux/amd64/drone-docker --help
 
@@ -329,7 +329,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/arm64/drone-docker ./cmd/drone-docker'
     environment:
@@ -340,7 +340,7 @@ steps:
           - tag
 
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/arm64/drone-docker ./cmd/drone-docker'
     environment:
@@ -350,7 +350,7 @@ steps:
         - tag
 
   - name: executable
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - ./release/linux/arm64/drone-docker --help
 
@@ -429,7 +429,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/amd64/drone-gcr ./cmd/drone-gcr'
     environment:
@@ -440,7 +440,7 @@ steps:
           - tag
 
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/amd64/drone-gcr ./cmd/drone-gcr'
     environment:
@@ -488,7 +488,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/arm64/drone-gcr ./cmd/drone-gcr'
     environment:
@@ -499,7 +499,7 @@ steps:
           - tag
 
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/arm64/drone-gcr ./cmd/drone-gcr'
     environment:
@@ -582,7 +582,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/amd64/drone-gar ./cmd/drone-gar'
     environment:
@@ -593,7 +593,7 @@ steps:
           - tag
 
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/amd64/drone-gar ./cmd/drone-gar'
     environment:
@@ -641,7 +641,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/arm64/drone-gar ./cmd/drone-gar'
     environment:
@@ -652,7 +652,7 @@ steps:
           - tag
 
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/arm64/drone-gar ./cmd/drone-gar'
     environment:
@@ -734,7 +734,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/amd64/drone-ecr ./cmd/drone-ecr'
     environment:
@@ -744,7 +744,7 @@ steps:
         exclude:
           - tag
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/amd64/drone-ecr ./cmd/drone-ecr'
     environment:
@@ -792,7 +792,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/arm64/drone-ecr ./cmd/drone-ecr'
     environment:
@@ -802,7 +802,7 @@ steps:
         exclude:
           - tag
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/arm64/drone-ecr ./cmd/drone-ecr'
     environment:
@@ -885,7 +885,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/amd64/drone-heroku ./cmd/drone-heroku'
     environment:
@@ -895,7 +895,7 @@ steps:
         exclude:
           - tag
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/amd64/drone-heroku ./cmd/drone-heroku'
     environment:
@@ -944,7 +944,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_COMMIT_SHA:0:8}" -a -tags netgo -o release/linux/arm64/drone-heroku ./cmd/drone-heroku'
     environment:
@@ -954,7 +954,7 @@ steps:
         exclude:
           - tag
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v}" -a -tags netgo -o release/linux/arm64/drone-heroku ./cmd/drone-heroku'
     environment:
@@ -1035,7 +1035,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.build=${DRONE_BUILD_NUMBER}" -a -tags netgo -o release/linux/amd64/drone-acr ./cmd/drone-acr'
     environment:
@@ -1045,7 +1045,7 @@ steps:
         exclude:
           - tag
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v} -X main.build=${DRONE_BUILD_NUMBER}" -a -tags netgo -o release/linux/amd64/drone-acr ./cmd/drone-acr'
     environment:
@@ -1093,7 +1093,7 @@ platform:
 
 steps:
   - name: build-push
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.build=${DRONE_BUILD_NUMBER}" -a -tags netgo -o release/linux/arm64/drone-acr ./cmd/drone-acr'
     environment:
@@ -1104,7 +1104,7 @@ steps:
           - tag
 
   - name: build-tag
-    image: golang:1.22.4
+    image: golang:1.23
     commands:
       - 'go build -v -ldflags "-X main.version=${DRONE_TAG##v} -X main.build=${DRONE_BUILD_NUMBER}" -a -tags netgo -o release/linux/arm64/drone-acr ./cmd/drone-acr'
     environment:

.harness/eventPR.yaml

@@ -0,0 +1,15 @@
+inputSet:
+  name: event-PR
+  tags: {}
+  identifier: eventPR
+  orgIdentifier: default
+  projectIdentifier: Drone_Plugins
+  pipeline:
+    identifier: dronedockerharness
+    properties:
+      ci:
+        codebase:
+          build:
+            type: PR
+            spec:
+              number: <+trigger.prNumber>

.harness/eventPush.yaml

@@ -0,0 +1,15 @@
+inputSet:
+  name: event-Push
+  tags: {}
+  identifier: eventPush
+  orgIdentifier: default
+  projectIdentifier: Drone_Plugins
+  pipeline:
+    identifier: dronedockerharness
+    properties:
+      ci:
+        codebase:
+          build:
+            type: branch
+            spec:
+              branch: <+trigger.branch>

.harness/eventTag.yaml

@@ -0,0 +1,15 @@
+inputSet:
+  name: event-Tag
+  tags: {}
+  identifier: eventTag
+  orgIdentifier: default
+  projectIdentifier: Drone_Plugins
+  pipeline:
+    identifier: dronedockerharness
+    properties:
+      ci:
+        codebase:
+          build:
+            type: tag
+            spec:
+              tag: <+trigger.tag>

.harness/harness.yaml

@@ -0,0 +1,447 @@
+pipeline:
+  orgIdentifier: default
+  tags: {}
+  properties:
+    ci:
+      codebase:
+        connectorRef: GitHub_Drone_Plugins_Org
+        repoName: drone-docker
+        build: <+input>
+        sparseCheckout: []
+  stages:
+    - stage:
+        name: Test
+        identifier: Test
+        description: ""
+        type: CI
+        spec:
+          cloneCodebase: true
+          caching:
+            enabled: false
+            paths: []
+          platform:
+            os: Linux
+            arch: Amd64
+          runtime:
+            type: Cloud
+            spec: {}
+          execution:
+            steps:
+              - step:
+                  type: Run
+                  name: GO VET
+                  identifier: Run_1
+                  spec:
+                    connectorRef: Plugins_Docker_Hub_Connector
+                    image: golang:1.24.11
+                    shell: Sh
+                    command: go vet ./...
+              - step:
+                  type: Run
+                  name: GO TEST
+                  identifier: Run_2
+                  spec:
+                    connectorRef: Plugins_Docker_Hub_Connector
+                    image: golang:1.24.11
+                    shell: Sh
+                    command: go test -cover ./...
+    - parallel:
+        - stage:
+            name: linux-amd64
+            identifier: linamd64
+            description: ""
+            type: CI
+            spec:
+              cloneCodebase: true
+              caching:
+                enabled: false
+                paths: []
+              platform:
+                os: Linux
+                arch: Amd64
+              runtime:
+                type: Cloud
+                spec: {}
+              execution:
+                steps:
+                  - step:
+                      type: Run
+                      name: Build Binary
+                      identifier: Build_Push
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        image: golang:1.24.11
+                        shell: Sh
+                        command: go build -a -tags netgo -o release/linux/amd64/drone-<+matrix.repo> ./cmd/drone-<+matrix.repo>
+                        envVariables:
+                          CGO_ENABLED: "0"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - heroku
+                            - acr
+                  - step:
+                      type: Plugin
+                      name: Build and Push on Tag
+                      identifier: Docker_Build_and_Push
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        image: plugins/docker
+                        settings:
+                          username: drone
+                          password: <+secrets.getValue("Plugins_Docker_Hub_Pat")>
+                          repo: plugins/<+matrix.repo>
+                          dockerfile: docker/<+matrix.repo>/Dockerfile.linux.amd64
+                          auto_tag: "true"
+                          auto_tag_suffix: linux-amd64
+                      when:
+                        stageStatus: Success
+                        condition: <+codebase.build.type> == "tag"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - heroku
+                            - acr
+                  - step:
+                      type: BuildAndPushDockerRegistry
+                      name: Build and Push on Branch
+                      identifier: BuildAndPushDockerRegistry_1
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        repo: plugins/<+matrix.repo>
+                        tags:
+                          - linux-amd64
+                        caching: false
+                        dockerfile: docker/<+matrix.repo>/Dockerfile.linux.amd64
+                      when:
+                        stageStatus: Success
+                        condition: <+codebase.build.type> == "branch"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - heroku
+                            - acr
+        - stage:
+            name: linux-arm64
+            identifier: linarm64
+            description: ""
+            type: CI
+            spec:
+              cloneCodebase: true
+              caching:
+                enabled: false
+                paths: []
+              platform:
+                os: Linux
+                arch: Arm64
+              runtime:
+                type: Cloud
+                spec: {}
+              execution:
+                steps:
+                  - step:
+                      type: Run
+                      name: Build Binary
+                      identifier: buildpush
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        image: golang:1.24.11
+                        shell: Sh
+                        command: go build -a -tags netgo -o release/linux/arm64/drone-<+matrix.repo> ./cmd/drone-<+matrix.repo>
+                        envVariables:
+                          CGO_ENABLED: "0"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - heroku
+                            - acr
+                  - step:
+                      type: Plugin
+                      name: Build and Push on Tag
+                      identifier: Docker_Build_and_Push
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        image: plugins/docker
+                        settings:
+                          username: drone
+                          password: <+secrets.getValue("Plugins_Docker_Hub_Pat")>
+                          repo: plugins/<+matrix.repo>
+                          dockerfile: docker/<+matrix.repo>/Dockerfile.linux.arm64
+                          auto_tag: "true"
+                          auto_tag_suffix: linux-arm64
+                      when:
+                        stageStatus: Success
+                        condition: <+codebase.build.type> == "tag"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - heroku
+                            - acr
+                  - step:
+                      type: BuildAndPushDockerRegistry
+                      name: Build and Push on Branch
+                      identifier: BuildAndPushDockerRegistry_1
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        repo: plugins/<+matrix.repo>
+                        tags:
+                          - linux-arm64
+                        caching: false
+                        dockerfile: docker/<+matrix.repo>/Dockerfile.linux.arm64
+                      when:
+                        stageStatus: Success
+                        condition: <+codebase.build.type> == "branch"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - heroku
+                            - acr
+        - stage:
+            name: win-1809-amd64
+            identifier: win1809amd64
+            description: ""
+            type: CI
+            spec:
+              cloneCodebase: true
+              caching:
+                enabled: true
+              infrastructure:
+                type: VM
+                spec:
+                  type: Pool
+                  spec:
+                    poolName: windows-2019
+                    os: Windows
+              execution:
+                steps:
+                  - step:
+                      type: Run
+                      name: Build Binary
+                      identifier: go_build
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        image: golang:1.23.0
+                        shell: Sh
+                        command: |-
+                          # disable cgo
+                          export CGO_ENABLED=0
+
+                          go build -o release/windows/amd64/drone-<+matrix.repo>.exe ./cmd/drone-<+matrix.repo>
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - acr
+                  - step:
+                      type: Plugin
+                      name: Build and Push on Tag
+                      identifier: Docker_Build_and_Push1
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        image: plugins/docker
+                        settings:
+                          username: drone
+                          password: <+secrets.getValue("Plugins_Docker_Hub_Pat")>
+                          repo: plugins/<+matrix.repo>
+                          dockerfile: docker/<+matrix.repo>/Dockerfile.windows.amd64.1809
+                          auto_tag: "true"
+                          auto_tag_suffix: windows-1809-amd64
+                      when:
+                        stageStatus: Success
+                        condition: <+codebase.build.type> == "tag"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - acr
+                  - step:
+                      type: BuildAndPushDockerRegistry
+                      name: Build and Push on Branch
+                      identifier: BuildAndPushDockerRegistry_2
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        repo: plugins/<+matrix.repo>
+                        tags:
+                          - windows-1809-amd64
+                        caching: false
+                        dockerfile: docker/<+matrix.repo>/Dockerfile.windows.amd64.1809
+                      when:
+                        stageStatus: Success
+                        condition: <+codebase.build.type> == "branch"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - acr
+            delegateSelectors:
+              - windows-vm
+        - stage:
+            name: win-ltsc2022-amd64
+            identifier: winamd64
+            description: ""
+            type: CI
+            spec:
+              cloneCodebase: true
+              caching:
+                enabled: false
+                paths: []
+              platform:
+                os: Windows
+                arch: Amd64
+              runtime:
+                type: Cloud
+                spec: {}
+              execution:
+                steps:
+                  - step:
+                      type: Run
+                      name: Build Binary -ltsc2022
+                      identifier: build_amd64ltsc2022
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        image: golang:1.23.0
+                        shell: Sh
+                        command: |-
+                          # disable cgo
+                          export CGO_ENABLED=0
+
+                          go build -o release/windows/amd64/drone-<+matrix.repo>.exe ./cmd/drone-<+matrix.repo>
+                        envVariables:
+                          CGO_ENABLED: "0"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - acr
+                  - step:
+                      type: Plugin
+                      name: Build and Push on Tag
+                      identifier: Docker_Build_and_Push1
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        image: plugins/docker
+                        settings:
+                          username: drone
+                          password: <+secrets.getValue("Plugins_Docker_Hub_Pat")>
+                          repo: plugins/<+matrix.repo>
+                          dockerfile: docker/<+matrix.repo>/Dockerfile.windows.amd64.ltsc2022
+                          auto_tag: "true"
+                          auto_tag_suffix: windows-ltsc2022-amd64
+                      when:
+                        stageStatus: Success
+                        condition: <+codebase.build.type> == "tag"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - acr
+                  - step:
+                      type: BuildAndPushDockerRegistry
+                      name: Build and Push on Branch
+                      identifier: BuildAndPushDockerRegistry_2
+                      spec:
+                        connectorRef: Plugins_Docker_Hub_Connector
+                        repo: plugins/<+matrix.repo>
+                        tags:
+                          - windows-ltsc2022-amd64
+                        caching: false
+                        dockerfile: docker/<+matrix.repo>/Dockerfile.windows.amd64.ltsc2022
+                      when:
+                        stageStatus: Success
+                        condition: <+codebase.build.type> == "branch"
+                      strategy:
+                        matrix:
+                          repo:
+                            - docker
+                            - gcr
+                            - gar
+                            - ecr
+                            - acr
+              buildIntelligence:
+                enabled: false
+    - stage:
+        name: Manifest and Release
+        identifier: Manifest
+        description: ""
+        type: CI
+        spec:
+          cloneCodebase: true
+          caching:
+            enabled: false
+            paths: []
+          execution:
+            steps:
+              - step:
+                  type: Plugin
+                  name: Manifest
+                  identifier: Plugin_1
+                  spec:
+                    connectorRef: Plugins_Docker_Hub_Connector
+                    image: plugins/manifest
+                    settings:
+                      username: drone
+                      password: <+secrets.getValue("Plugins_Docker_Hub_Pat")>
+                      auto_tag: "true"
+                      ignore_missing: "true"
+                      spec: docker/<+matrix.repo>/manifest.tmpl
+                  when:
+                    stageStatus: Success
+                    condition: <+codebase.build.type> == "tag"
+                  strategy:
+                    matrix:
+                      repo:
+                        - docker
+                        - gcr
+                        - gar
+                        - ecr
+                        - heroku
+                        - acr
+          platform:
+            os: Linux
+            arch: Amd64
+          runtime:
+            type: Cloud
+            spec: {}
+  identifier: dronedockerharness
+  projectIdentifier: Drone_Plugins
+  name: drone-docker-harness
+  allowStageExecutions: true

COSIGN_USAGE.md

@@ -0,0 +1,162 @@
+# Cosign Integration for Drone-Docker
+
+This document describes how to use the cosign container image signing feature in drone-docker.
+
+## Overview
+
+The drone-docker plugin now supports automatic container image signing using cosign after each successful push. This provides cryptographic verification that images haven't been tampered with.
+
+## Environment Variables
+
+The plugin accepts three cosign-related environment variables:
+
+### `PLUGIN_COSIGN_PRIVATE_KEY` (Required for signing)
+- **Description**: Private key for signing (PEM format content or file path)
+- **Format**: Either PEM content or file path to private key
+- **Usage**: Should be provided via secrets
+
+### `PLUGIN_COSIGN_PASSWORD` (Optional)
+- **Description**: Password for encrypted private keys
+- **Usage**: Only needed if your private key is password-protected
+
+### `PLUGIN_COSIGN_PARAMS` (Optional)
+- **Description**: Additional cosign parameters
+- **Examples**: 
+  - `-a build_id=123` (add annotations)
+  - `--tlog-upload=false` (disable transparency log)
+  - `--rekor-url=https://custom-rekor.example.com` (custom rekor instance)
+
+## Usage Examples
+
+### 1. Basic Signing (Drone)
+
+```yaml
+kind: pipeline
+type: docker
+name: default
+
+steps:
+- name: docker
+  image: plugins/docker
+  settings:
+    repo: myregistry/myapp
+    tags: latest
+    cosign_private_key:
+      from_secret: cosign_private_key
+    cosign_password:
+      from_secret: cosign_password
+```
+
+### 2. Advanced Signing with Annotations (Drone)
+
+```yaml
+steps:
+- name: docker
+  image: plugins/docker
+  settings:
+    repo: myregistry/myapp
+    tags: 
+      - latest
+      - ${DRONE_BUILD_NUMBER}
+    cosign_private_key:
+      from_secret: cosign_private_key
+    cosign_params: "-a build_id=${DRONE_BUILD_NUMBER} -a commit_sha=${DRONE_COMMIT_SHA} -a branch=${DRONE_BRANCH}"
+```
+
+### 3. Harness CI/CD Usage
+
+```yaml
+- step:
+    type: Plugin
+    name: Build and Sign
+    identifier: build_and_sign
+    spec:
+      connectorRef: account.harnessImage
+      image: plugins/docker
+      settings:
+        repo: myregistry/myapp
+        tags: <+pipeline.sequenceId>
+        cosign_private_key: <+secrets.getValue("cosign_private_key")>
+        cosign_password: <+secrets.getValue("cosign_password")>
+        cosign_params: "-a harness_build=<+pipeline.sequenceId> -a harness_project=<+project.name>"
+```
+
+## Key Management
+
+### Generating Cosign Keys
+
+```bash
+# Generate a new key pair
+cosign generate-key-pair
+
+# This creates:
+# - cosign.key (private key) 
+# - cosign.pub (public key)
+```
+
+### Storing Keys Securely
+**Harness Secrets:**
+1. Go to Project Settings → Secrets
+2. Create new secret with type "File" for private key
+3. Create new secret with type "Text" for password
+
+## Security Features
+
+### Automatic Validation
+- ✅ **Private key format validation**: Ensures PEM format is correct
+- ✅ **Password requirement detection**: Warns if encrypted key needs password
+- ✅ **Keyless signing prevention**: Warns that OIDC keyless signing isn't supported
+
+### Error Handling
+- **Invalid private key**: `❌ Invalid private key format. Expected PEM format`
+- **Missing password**: `🔐 Encrypted private key requires password. Set PLUGIN_COSIGN_PASSWORD`
+- **Keyless signing**: `⚠️ WARNING: Keyless signing (OIDC) isn't supported yet in this plugin`
+
+## Signing Behavior
+
+### When Signing Occurs
+- ✅ **After each successful push**: Images are signed immediately after push
+- ✅ **Multiple tags**: Each tag gets signed individually
+- ✅ **Push-only mode**: Works with existing images
+- ✅ **Dry-run respect**: Skips signing in dry-run mode
+
+### Image References
+- **Preferred**: Signs by digest (e.g., `image@sha256:abc123...`) for security
+- **Fallback**: Signs by tag if digest unavailable
+
+### Authentication
+- **Registry auth**: Automatically uses existing Docker registry credentials
+
+## Verification
+
+To verify a signed image:
+
+```bash
+# Verify with public key
+cosign verify --key cosign.pub myregistry/myapp:latest
+
+# Verify with annotations
+cosign verify --key cosign.pub \
+  -a build_id=123 \
+  myregistry/myapp:latest
+```
+
+## Troubleshooting
+
+### Common Issues
+
+1. **"cosign: command not found"**
+   - The container image includes cosign binary
+   - Use the latest plugin image: `plugins/docker:latest`
+
+2. **"keyless signing not supported"**
+   - This plugin only supports private key signing
+   - Don't use `--oidc` or `--identity-token` in `cosign_params`
+
+3. **"encrypted private key requires password"**
+   - Set `PLUGIN_COSIGN_PASSWORD` environment variable
+   - Or use an unencrypted private key
+
+4. **Registry authentication issues**
+   - Cosign uses the same Docker registry credentials
+   - Ensure Docker login is working first

card.go

@@ -17,8 +17,14 @@ import (
 	"github.com/inhies/go-bytesize"
 )
 
+// writeCard maintains backward compatibility by using TempTag
 func (p Plugin) writeCard() error {
-	cmd := exec.Command(dockerExe, "inspect", p.Build.TempTag)
+	return p.writeCardForImage(p.Build.TempTag)
+}
+
+// writeCardForImage generates card for any image reference
+func (p Plugin) writeCardForImage(imageRef string) error {
+	cmd := exec.Command(dockerExe, "inspect", imageRef)
 	data, err := cmd.CombinedOutput()
 	if err != nil {
 		return err
@@ -38,7 +44,11 @@ func (p Plugin) writeCard() error {
 	for _, tag := range inspect.RepoTags {
 		sliceTagStruct = append(sliceTagStruct, TagStruct{Tag: tag})
 	}
-	inspect.ParsedRepoTags = sliceTagStruct[1:] // remove the first tag which is always "hash:latest"
+	if len(sliceTagStruct) > 1 {
+		inspect.ParsedRepoTags = sliceTagStruct[1:] // remove the first tag which is always "hash:latest"
+	} else {
+		inspect.ParsedRepoTags = sliceTagStruct
+	}
 	// create the url from repo and registry
 	inspect.URL = mapRegistryToURL(p.Daemon.Registry, p.Build.Repo)
 	cardData, _ := json.Marshal(inspect)

cmd/drone-acr/main.go

@@ -1,15 +1,50 @@
 package main
 
 import (
+	"context"
+	"encoding/base64"
+	"encoding/json"
 	"fmt"
+	"io/ioutil"
+	"net/http"
+	"net/url"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strings"
 
+	"github.com/Azure/azure-sdk-for-go/sdk/azcore/policy"
+	"github.com/Azure/azure-sdk-for-go/sdk/azidentity"
 	"github.com/joho/godotenv"
+	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 
 	docker "github.com/drone-plugins/drone-docker"
+	azureutil "github.com/drone-plugins/drone-docker/internal/azure"
+)
+
+type subscriptionUrlResponse struct {
+	Value []struct {
+		ID string `json:"id"`
+	} `json:"value"`
+}
+
+const (
+	acrCertFile              = "acr-cert.pem"
+	azSubscriptionApiVersion = "2021-04-01"
+	azSubscriptionBaseUrl    = "https://management.azure.com/subscriptions/"
+	basePublicUrl            = "https://portal.azure.com/#view/Microsoft_Azure_ContainerRegistries/TagMetadataBlade/registryId/"
+	defaultUsername          = "00000000-0000-0000-0000-000000000000"
+
+	// Environment variable names for Azure Environment Credential
+	clientIdEnv        = "AZURE_CLIENT_ID"
+	clientSecretKeyEnv = "AZURE_CLIENT_SECRET"
+	tenantKeyEnv       = "AZURE_TENANT_ID"
+	certPathEnv        = "AZURE_CLIENT_CERTIFICATE_PATH"
+)
+
+var (
+	acrCertPath = filepath.Join(os.TempDir(), acrCertFile)
 )
 
 func main() {
@@ -21,8 +56,21 @@ func main() {
 	var (
 		repo     = getenv("PLUGIN_REPO")
 		registry = getenv("PLUGIN_REGISTRY")
+
+		// If these credentials are provided, they will be directly used
+		// for docker login
 		username = getenv("SERVICE_PRINCIPAL_CLIENT_ID")
 		password = getenv("SERVICE_PRINCIPAL_CLIENT_SECRET")
+
+		// Service principal credentials
+		clientId       = getenv("CLIENT_ID", "AZURE_CLIENT_ID", "AZURE_APP_ID", "PLUGIN_CLIENT_ID")
+		clientSecret   = getenv("CLIENT_SECRET", "PLUGIN_CLIENT_SECRET")
+		clientCert     = getenv("CLIENT_CERTIFICATE", "PLUGIN_CLIENT_CERTIFICATE")
+		tenantId       = getenv("TENANT_ID", "AZURE_TENANT_ID", "PLUGIN_TENANT_ID")
+		subscriptionId = getenv("SUBSCRIPTION_ID", "PLUGIN_SUBSCRIPTION_ID")
+		publicUrl      = getenv("DAEMON_REGISTRY", "PLUGIN_DAEMON_REGISTRY")
+		authorityHost  = getenv("AZURE_AUTHORITY_HOST", "PLUGIN_AZURE_AUTHORITY_HOST")
+		idToken        = getenv("PLUGIN_OIDC_TOKEN_ID")
 	)
 
 	// default registry value
@@ -30,6 +78,37 @@ func main() {
 		registry = "azurecr.io"
 	}
 
+	// Get auth if username and password is not specified
+	if username == "" && password == "" {
+		// docker login credentials are not provided
+		var err error
+		username = defaultUsername
+		if idToken != "" && clientId != "" && tenantId != "" {
+			logrus.Debug("Using OIDC authentication flow")
+			var aadToken string
+			aadToken, err = azureutil.GetAADAccessTokenViaClientAssertion(context.Background(), tenantId, clientId, idToken, authorityHost)
+			if err != nil {
+				logrus.Fatal(err)
+			}
+			var p string
+			p, err = getPublicUrl(aadToken, registry, subscriptionId)
+			if err == nil {
+				publicUrl = p
+			} else {
+				fmt.Fprintf(os.Stderr, "failed to get public url with error: %s\n", err)
+			}
+			password, err = fetchACRToken(tenantId, aadToken, registry)
+			if err != nil {
+				logrus.Fatal(err)
+			}
+		} else {
+			password, publicUrl, err = getAuth(clientId, clientSecret, clientCert, tenantId, subscriptionId, registry)
+			if err != nil {
+				logrus.Fatal(err)
+			}
+		}
+	}
+
 	// must use the fully qualified repo name. If the
 	// repo name does not have the registry prefix we
 	// should prepend.
@@ -42,6 +121,11 @@ func main() {
 	os.Setenv("DOCKER_USERNAME", username)
 	os.Setenv("DOCKER_PASSWORD", password)
 	os.Setenv("PLUGIN_REGISTRY_TYPE", "ACR")
+	if publicUrl != "" {
+		// Set this env variable if public URL for artifact is available
+		// If not, we will fall back to registry url
+		os.Setenv("ARTIFACT_REGISTRY", publicUrl)
+	}
 
 	// invoke the base docker plugin binary
 	cmd := exec.Command(docker.GetDroneDockerExecCmd())
@@ -53,6 +137,157 @@ func main() {
 	}
 }
 
+func getAuth(clientId, clientSecret, clientCert, tenantId, subscriptionId, registry string) (string, string, error) {
+	// Verify inputs
+	if tenantId == "" {
+		return "", "", fmt.Errorf("tenantId cannot be empty for AAD authentication")
+	}
+	if clientId == "" {
+		return "", "", fmt.Errorf("clientId cannot be empty for AAD authentication")
+	}
+	if clientSecret == "" && clientCert == "" {
+		return "", "", fmt.Errorf("one of client secret or client cert should be defined")
+	}
+
+	// Setup cert
+	if clientCert != "" {
+		err := setupACRCert(clientCert, acrCertPath)
+		if err != nil {
+			errors.Wrap(err, "failed to push setup cert file")
+		}
+	}
+
+	// Get AZ env
+	if err := os.Setenv(clientIdEnv, clientId); err != nil {
+		return "", "", errors.Wrap(err, "failed to set env variable client Id")
+	}
+	if err := os.Setenv(clientSecretKeyEnv, clientSecret); err != nil {
+		return "", "", errors.Wrap(err, "failed to set env variable client secret")
+	}
+	if err := os.Setenv(tenantKeyEnv, tenantId); err != nil {
+		return "", "", errors.Wrap(err, "failed to set env variable tenant Id")
+	}
+	if err := os.Setenv(certPathEnv, acrCertPath); err != nil {
+		return "", "", errors.Wrap(err, "failed to set env variable cert path")
+	}
+	env, err := azidentity.NewEnvironmentCredential(nil)
+	if err != nil {
+		return "", "", errors.Wrap(err, "failed to get env credentials from azure")
+	}
+	os.Unsetenv(clientIdEnv)
+	os.Unsetenv(clientSecretKeyEnv)
+	os.Unsetenv(tenantKeyEnv)
+	os.Unsetenv(certPathEnv)
+
+	// Fetch AAD token
+	policy := policy.TokenRequestOptions{
+		Scopes: []string{"https://management.azure.com/.default"},
+	}
+	aadToken, err := env.GetToken(context.Background(), policy)
+	if err != nil {
+		return "", "", errors.Wrap(err, "failed to fetch access token")
+	}
+
+	// Get public URL for artifacts
+	publicUrl, err := getPublicUrl(aadToken.Token, registry, subscriptionId)
+	if err != nil {
+		// execution should not fail because of this error
+		fmt.Fprintf(os.Stderr, "failed to get public url with error: %s\n", err)
+	}
+
+	// Fetch token
+	ACRToken, err := fetchACRToken(tenantId, aadToken.Token, registry)
+	if err != nil {
+		return "", "", errors.Wrap(err, "failed to fetch ACR token")
+	}
+	return ACRToken, publicUrl, nil
+}
+
+func fetchACRToken(tenantId, token, registry string) (string, error) {
+	// oauth exchange
+	formData := url.Values{
+		"grant_type":   {"access_token"},
+		"service":      {registry},
+		"tenant":       {tenantId},
+		"access_token": {token},
+	}
+	jsonResponse, err := http.PostForm(fmt.Sprintf("https://%s/oauth2/exchange", registry), formData)
+	if err != nil || jsonResponse == nil {
+		return "", errors.Wrap(err, "failed to fetch ACR token")
+	}
+
+	// fetch token from response
+	var response map[string]interface{}
+	err = json.NewDecoder(jsonResponse.Body).Decode(&response)
+	if err != nil {
+		return "", errors.Wrap(err, "failed to decode oauth exchange response")
+	}
+
+	// Parse the refresh_token from the response
+	if t, found := response["refresh_token"]; found {
+		if refreshToken, ok := t.(string); ok {
+			return refreshToken, nil
+		}
+		return "", errors.New("failed to cast refresh token from acr")
+	}
+	return "", errors.Wrap(err, "refresh token not found in response of oauth exchange call")
+}
+
+func setupACRCert(cert, certPath string) error {
+	decoded, err := base64.StdEncoding.DecodeString(cert)
+	if err != nil {
+		return errors.Wrap(err, "failed to base64 decode ACR certificate")
+	}
+	err = ioutil.WriteFile(certPath, decoded, 0644)
+	if err != nil {
+		return errors.Wrap(err, "failed to write ACR certificate")
+	}
+	return nil
+}
+
+func getPublicUrl(token, registryUrl, subscriptionId string) (string, error) {
+	if len(subscriptionId) == 0 || registryUrl == "" {
+		return "", nil
+	}
+
+	registry := strings.Split(registryUrl, ".")[0]
+	filter := fmt.Sprintf("resourceType eq 'Microsoft.ContainerRegistry/registries' and name eq '%s'", registry)
+	params := url.Values{}
+	params.Add("$filter", filter)
+	params.Add("api-version", azSubscriptionApiVersion)
+	params.Add("$select", "id")
+	url := azSubscriptionBaseUrl + subscriptionId + "/resources?" + params.Encode()
+
+	client := &http.Client{}
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		fmt.Println(err)
+		return "", errors.Wrap(err, "failed to create request for getting container registry setting")
+	}
+
+	req.Header.Add("Authorization", "Bearer "+token)
+	res, err := client.Do(req)
+	if err != nil {
+		fmt.Println(err)
+		return "", errors.Wrap(err, "failed to send request for getting container registry setting")
+	}
+	defer res.Body.Close()
+
+	var response subscriptionUrlResponse
+	err = json.NewDecoder(res.Body).Decode(&response)
+	if err != nil {
+		return "", errors.Wrap(err, "failed to send request for getting container registry setting")
+	}
+	if len(response.Value) == 0 {
+		return "", errors.New("no id present for base url")
+	}
+	return basePublicUrl + encodeParam(response.Value[0].ID), nil
+}
+
+func encodeParam(s string) string {
+	return url.QueryEscape(s)
+}
+
 func getenv(key ...string) (s string) {
 	for _, k := range key {
 		s = os.Getenv(k)

cmd/drone-acr/main_test.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+    "os"
+    "testing"
+)
+
+func TestGetAuthInputValidation(t *testing.T) {
+    // missing tenant
+    if _, _, err := getAuth("client", "secret", "", "", "sub", "registry.azurecr.io"); err == nil {
+        t.Fatalf("expected error for missing tenantId")
+    }
+    // missing clientId
+    if _, _, err := getAuth("", "secret", "", "tenant", "sub", "registry.azurecr.io"); err == nil {
+        t.Fatalf("expected error for missing clientId")
+    }
+    // missing both secret and cert
+    if _, _, err := getAuth("client", "", "", "tenant", "sub", "registry.azurecr.io"); err == nil {
+        t.Fatalf("expected error for missing credentials")
+    }
+}
+
+func TestGetenvAuthorityHost(t *testing.T) {
+    os.Setenv("AZURE_AUTHORITY_HOST", "https://login.microsoftonline.us")
+    defer os.Unsetenv("AZURE_AUTHORITY_HOST")
+
+    got := getenv("AZURE_AUTHORITY_HOST")
+    if got != "https://login.microsoftonline.us" {
+        t.Fatalf("expected AZURE_AUTHORITY_HOST to be returned, got %q", got)
+    }
+}
+

cmd/drone-docker/custom_string_slice.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"strings"
+)
+
+// CustomStringSliceFlag is like a regular StringSlice flag but with
+// semicolon as a delimiter
+type CustomStringSliceFlag struct {
+	Value []string
+}
+
+func (f *CustomStringSliceFlag) GetValue() []string {
+	if f.Value == nil {
+		return make([]string, 0)
+	}
+	return f.Value
+}
+
+func (f *CustomStringSliceFlag) String() string {
+	if f.Value == nil {
+		return ""
+	}
+	return strings.Join(f.Value, ";")
+}
+
+func (f *CustomStringSliceFlag) Set(v string) error {
+	for _, s := range strings.Split(v, ";") {
+		s = strings.TrimSpace(s)
+		f.Value = append(f.Value, s)
+	}
+	return nil
+}

cmd/drone-docker/main.go

@@ -33,7 +33,7 @@ func main() {
 		cli.BoolFlag{
 			Name:   "dry-run",
 			Usage:  "dry run disables docker push",
-			EnvVar: "PLUGIN_DRY_RUN",
+			EnvVar: "PLUGIN_DRY_RUN, PLUGIN_NO_PUSH",
 		},
 		cli.StringFlag{
 			Name:   "remote.url",
@@ -151,6 +151,17 @@ func main() {
 			Usage:  "build args",
 			EnvVar: "PLUGIN_BUILD_ARGS_FROM_ENV",
 		},
+		cli.GenericFlag{
+			Name:   "args-new",
+			Usage:  "build args new",
+			EnvVar: "PLUGIN_BUILD_ARGS_NEW",
+			Value:  new(CustomStringSliceFlag),
+		},
+		cli.BoolFlag{
+			Name:   "plugin-multiple-build-agrs",
+			Usage:  "plugin multiple build agrs",
+			EnvVar: "PLUGIN_MULTIPLE_BUILD_ARGS",
+		},
 		cli.BoolFlag{
 			Name:   "quiet",
 			Usage:  "quiet docker build",
@@ -312,6 +323,32 @@ func main() {
 			Usage:  "access token",
 			EnvVar: "ACCESS_TOKEN",
 		},
+		// Cosign signing configuration
+		cli.StringFlag{
+			Name:   "cosign.private-key",
+			Usage:  "cosign private key content or file path for signing",
+			EnvVar: "PLUGIN_COSIGN_PRIVATE_KEY",
+		},
+		cli.StringFlag{
+			Name:   "cosign.password",
+			Usage:  "password for encrypted cosign private key",
+			EnvVar: "PLUGIN_COSIGN_PASSWORD",
+		},
+		cli.StringFlag{
+			Name:   "cosign.params",
+			Usage:  "additional cosign parameters (e.g., annotations, flags)",
+			EnvVar: "PLUGIN_COSIGN_PARAMS",
+		},
+		cli.BoolFlag{
+			Name:   "push-only",
+			Usage:  "skip build and only push images",
+			EnvVar: "PLUGIN_PUSH_ONLY",
+		},
+		cli.StringFlag{
+			Name:   "source-image",
+			Usage:  "source image to tag and push (format: repo:tag)",
+			EnvVar: "PLUGIN_SOURCE_IMAGE",
+		},
 	}
 
 	if err := app.Run(os.Args); err != nil {
@@ -339,32 +376,34 @@ func run(c *cli.Context) error {
 		CardPath:     c.String("drone-card-path"),
 		ArtifactFile: c.String("artifact-file"),
 		Build: docker.Build{
-			Remote:      c.String("remote.url"),
+			Remote:              c.String("remote.url"),
-			Name:        c.String("commit.sha"),
+			Name:                c.String("commit.sha"),
-			TempTag:     generateTempTag(),
+			TempTag:             generateTempTag(),
-			Dockerfile:  c.String("dockerfile"),
+			Dockerfile:          c.String("dockerfile"),
-			Context:     c.String("context"),
+			Context:             c.String("context"),
-			Tags:        c.StringSlice("tags"),
+			Tags:                c.StringSlice("tags"),
-			Args:        c.StringSlice("args"),
+			Args:                c.StringSlice("args"),
-			ArgsEnv:     c.StringSlice("args-from-env"),
+			ArgsEnv:             c.StringSlice("args-from-env"),
-			Target:      c.String("target"),
+			ArgsNew:             c.Generic("args-new").(*CustomStringSliceFlag).GetValue(),
-			Squash:      c.Bool("squash"),
+			IsMultipleBuildArgs: c.Bool("plugin-multiple-build-agrs"),
-			Pull:        c.BoolT("pull-image"),
+			Target:              c.String("target"),
-			CacheFrom:   c.StringSlice("cache-from"),
+			Squash:              c.Bool("squash"),
-			Compress:    c.Bool("compress"),
+			Pull:                c.BoolT("pull-image"),
-			Repo:        c.String("repo"),
+			CacheFrom:           c.StringSlice("cache-from"),
-			Labels:      c.StringSlice("custom-labels"),
+			Compress:            c.Bool("compress"),
-			LabelSchema: c.StringSlice("label-schema"),
+			Repo:                c.String("repo"),
-			AutoLabel:   c.BoolT("auto-label"),
+			Labels:              c.StringSlice("custom-labels"),
-			Link:        c.String("link"),
+			LabelSchema:         c.StringSlice("label-schema"),
-			NoCache:     c.Bool("no-cache"),
+			AutoLabel:           c.BoolT("auto-label"),
-			Secret:      c.String("secret"),
+			Link:                c.String("link"),
-			SecretEnvs:  c.StringSlice("secrets-from-env"),
+			NoCache:             c.Bool("no-cache"),
-			SecretFiles: c.StringSlice("secrets-from-file"),
+			Secret:              c.String("secret"),
-			AddHost:     c.StringSlice("add-host"),
+			SecretEnvs:          c.StringSlice("secrets-from-env"),
-			Quiet:       c.Bool("quiet"),
+			SecretFiles:         c.StringSlice("secrets-from-file"),
-			Platform:    c.String("platform"),
+			AddHost:             c.StringSlice("add-host"),
-			SSHAgentKey: c.String("ssh-agent-key"),
+			Quiet:               c.Bool("quiet"),
+			Platform:            c.String("platform"),
+			SSHAgentKey:         c.String("ssh-agent-key"),
 		},
 		Daemon: docker.Daemon{
 			Registry:      c.String("docker.registry"),
@@ -385,6 +424,13 @@ func run(c *cli.Context) error {
 		BaseImageRegistry: c.String("docker.baseimageregistry"),
 		BaseImageUsername: c.String("docker.baseimageusername"),
 		BaseImagePassword: c.String("docker.baseimagepassword"),
+		Cosign: docker.CosignConfig{
+			PrivateKey: c.String("cosign.private-key"),
+			Password:   c.String("cosign.password"),
+			Params:     c.String("cosign.params"),
+		},
+		PushOnly:    c.Bool("push-only"),
+		SourceImage: c.String("source-image"),
 	}
 
 	if c.Bool("tags.auto") {

cmd/drone-ecr/main.go

@@ -22,6 +22,10 @@ import (
 	docker "github.com/drone-plugins/drone-docker"
 )
 
+type ecrAPI interface {
+	DescribeImages(*ecr.DescribeImagesInput) (*ecr.DescribeImagesOutput, error)
+}
+
 const defaultRegion = "us-east-1"
 
 func main() {
@@ -31,18 +35,19 @@ func main() {
 	}
 
 	var (
-		repo             = getenv("PLUGIN_REPO")
+		repo                = getenv("PLUGIN_REPO")
-		registry         = getenv("PLUGIN_REGISTRY")
+		registry            = getenv("PLUGIN_REGISTRY")
-		region           = getenv("PLUGIN_REGION", "ECR_REGION", "AWS_REGION")
+		region              = getenv("PLUGIN_REGION", "ECR_REGION", "AWS_REGION")
-		key              = getenv("PLUGIN_ACCESS_KEY", "ECR_ACCESS_KEY", "AWS_ACCESS_KEY_ID")
+		key                 = getenv("PLUGIN_ACCESS_KEY", "ECR_ACCESS_KEY", "AWS_ACCESS_KEY_ID")
-		secret           = getenv("PLUGIN_SECRET_KEY", "ECR_SECRET_KEY", "AWS_SECRET_ACCESS_KEY")
+		secret              = getenv("PLUGIN_SECRET_KEY", "ECR_SECRET_KEY", "AWS_SECRET_ACCESS_KEY")
-		create           = parseBoolOrDefault(false, getenv("PLUGIN_CREATE_REPOSITORY", "ECR_CREATE_REPOSITORY"))
+		create              = parseBoolOrDefault(false, getenv("PLUGIN_CREATE_REPOSITORY", "ECR_CREATE_REPOSITORY"))
-		lifecyclePolicy  = getenv("PLUGIN_LIFECYCLE_POLICY")
+		lifecyclePolicy     = getenv("PLUGIN_LIFECYCLE_POLICY")
-		repositoryPolicy = getenv("PLUGIN_REPOSITORY_POLICY")
+		repositoryPolicy    = getenv("PLUGIN_REPOSITORY_POLICY")
-		assumeRole       = getenv("PLUGIN_ASSUME_ROLE")
+		assumeRole          = getenv("PLUGIN_ASSUME_ROLE")
-		externalId       = getenv("PLUGIN_EXTERNAL_ID")
+		externalId          = getenv("PLUGIN_EXTERNAL_ID")
-		scanOnPush       = parseBoolOrDefault(false, getenv("PLUGIN_SCAN_ON_PUSH"))
+		scanOnPush          = parseBoolOrDefault(false, getenv("PLUGIN_SCAN_ON_PUSH"))
-		idToken          = os.Getenv("PLUGIN_OIDC_TOKEN_ID")
+		idToken             = os.Getenv("PLUGIN_OIDC_TOKEN_ID")
+		skipPushIfTagExists = parseBoolOrDefault(false, getenv("PLUGIN_SKIP_PUSH_IF_TAG_EXISTS"))
 	)
 
 	// set the region
@@ -114,6 +119,34 @@ func main() {
 	os.Setenv("DOCKER_PASSWORD", password)
 	os.Setenv("PLUGIN_REGISTRY_TYPE", "ECR")
 
+	// Skip if tag already exits for both mutable and immutable repos
+	if skipPushIfTagExists {
+		tagInput := getenv("PLUGIN_TAG", "PLUGIN_TAGS")
+		var tags []string
+		if tagInput == "" {
+			tags = []string{"latest"}
+		} else {
+			for _, t := range strings.Split(tagInput, ",") {
+				trimmed := strings.TrimSpace(t)
+				if trimmed != "" {
+					tags = append(tags, trimmed)
+				}
+			}
+		}
+
+		repositoryName := trimHostname(repo, registry)
+		for _, t := range tags {
+			exists, err := tagExists(svc, repositoryName, t)
+			if err != nil {
+				logrus.Fatalf("Error checking if image exists for tag %s: %v", t, err)
+			}
+			if exists {
+				logrus.Infof("%s:%s: Image tag exists. Skipping push.", repo, t)
+				os.Exit(0)
+			}
+		}
+	}
+
 	// invoke the base docker plugin binary
 	cmd := exec.Command(docker.GetDroneDockerExecCmd())
 	cmd.Stdout = os.Stdout
@@ -249,3 +282,20 @@ func getECRClient(sess *session.Session, role string, externalId string, idToken
 		})
 	}
 }
+
+func tagExists(svc ecrAPI, repository, tag string) (bool, error) {
+	input := &ecr.DescribeImagesInput{
+		RepositoryName: aws.String(repository),
+		ImageIds: []*ecr.ImageIdentifier{
+			{ImageTag: aws.String(tag)},
+		},
+	}
+	output, err := svc.DescribeImages(input)
+	if err != nil {
+		if aerr, ok := err.(awserr.Error); ok && aerr.Code() == "ImageNotFoundException" {
+			return false, nil
+		}
+		return false, err
+	}
+	return len(output.ImageDetails) > 0, nil
+}

daemon.go

@@ -11,6 +11,7 @@ import (
 const dockerExe = "/usr/local/bin/docker"
 const dockerdExe = "/usr/local/bin/dockerd"
 const dockerHome = "/root/.docker/"
+const cosignExe = "/usr/local/bin/cosign"
 
 func (p Plugin) startDaemon() {
 	cmd := commandDaemon(p.Daemon)

daemon_win.go

@@ -1,3 +1,4 @@
+//go:build windows
 // +build windows
 
 package docker
@@ -5,6 +6,7 @@ package docker
 const dockerExe = "C:\\bin\\docker.exe"
 const dockerdExe = ""
 const dockerHome = "C:\\ProgramData\\docker\\"
+const cosignExe = "C:\\bin\\cosign.exe"
 
 func (p Plugin) startDaemon() {
 	// this is a no-op on windows

docker.go

@@ -45,47 +45,59 @@ type (
 
 	// Build defines Docker build parameters.
 	Build struct {
-		Remote      string   // Git remote URL
+		Remote              string   // Git remote URL
-		Name        string   // Docker build using default named tag
+		Name                string   // Docker build using default named tag
-		TempTag     string   // Temporary tag used during docker build
+		TempTag             string   // Temporary tag used during docker build
-		Dockerfile  string   // Docker build Dockerfile
+		Dockerfile          string   // Docker build Dockerfile
-		Context     string   // Docker build context
+		Context             string   // Docker build context
-		Tags        []string // Docker build tags
+		Tags                []string // Docker build tags
-		Args        []string // Docker build args
+		Args                []string // Docker build args
-		ArgsEnv     []string // Docker build args from env
+		ArgsEnv             []string // Docker build args from env
-		Target      string   // Docker build target
+		ArgsNew             []string // docker build args which has comma seperated values
-		Squash      bool     // Docker build squash
+		IsMultipleBuildArgs bool     // env variable for fall back to old build args
-		Pull        bool     // Docker build pull
+		Target              string   // Docker build target
-		CacheFrom   []string // Docker build cache-from
+		Squash              bool     // Docker build squash
-		Compress    bool     // Docker build compress
+		Pull                bool     // Docker build pull
-		Repo        string   // Docker build repository
+		CacheFrom           []string // Docker build cache-from
-		LabelSchema []string // label-schema Label map
+		Compress            bool     // Docker build compress
-		AutoLabel   bool     // auto-label bool
+		Repo                string   // Docker build repository
-		Labels      []string // Label map
+		LabelSchema         []string // label-schema Label map
-		Link        string   // Git repo link
+		AutoLabel           bool     // auto-label bool
-		NoCache     bool     // Docker build no-cache
+		Labels              []string // Label map
-		Secret      string   // secret keypair
+		Link                string   // Git repo link
-		SecretEnvs  []string // Docker build secrets with env var as source
+		NoCache             bool     // Docker build no-cache
-		SecretFiles []string // Docker build secrets with file as source
+		Secret              string   // secret keypair
-		AddHost     []string // Docker build add-host
+		SecretEnvs          []string // Docker build secrets with env var as source
-		Quiet       bool     // Docker build quiet
+		SecretFiles         []string // Docker build secrets with file as source
-		Platform    string   // Docker build platform
+		AddHost             []string // Docker build add-host
-		SSHAgentKey string   // Docker build ssh agent key
+		Quiet               bool     // Docker build quiet
-		SSHKeyPath  string   // Docker build ssh key path
+		Platform            string   // Docker build platform
+		SSHAgentKey         string   // Docker build ssh agent key
+		SSHKeyPath          string   // Docker build ssh key path
+	}
+
+	// CosignConfig defines Cosign signing parameters.
+	CosignConfig struct {
+		PrivateKey string // Private key content (PEM format) or file path
+		Password   string // Password for encrypted private keys
+		Params     string // Additional cosign parameters
 	}
 
 	// Plugin defines the Docker plugin parameters.
 	Plugin struct {
-		Login             Login  // Docker login configuration
+		Login             Login        // Docker login configuration
-		Build             Build  // Docker build configuration
+		Build             Build        // Docker build configuration
-		Daemon            Daemon // Docker daemon configuration
+		Daemon            Daemon       // Docker daemon configuration
-		Dryrun            bool   // Docker push is skipped
+		Cosign            CosignConfig // Cosign signing configuration
-		Cleanup           bool   // Docker purge is enabled
+		Dryrun            bool         // Docker push is skipped
-		CardPath          string // Card path to write file to
+		Cleanup           bool         // Docker purge is enabled
-		ArtifactFile      string // Artifact path to write file to
+		CardPath          string       // Card path to write file to
-		BaseImageRegistry string // Docker registry to pull base image
+		ArtifactFile      string       // Artifact path to write file to
-		BaseImageUsername string // Docker registry username to pull base image
+		BaseImageRegistry string       // Docker registry to pull base image
-		BaseImagePassword string // Docker registry password to pull base image
+		BaseImageUsername string       // Docker registry username to pull base image
+		BaseImagePassword string       // Docker registry password to pull base image
+		PushOnly          bool         // Push only mode, skips build process
+		SourceImage       string       // Source image to push (optional)
 	}
 
 	Card []struct {
@@ -172,10 +184,10 @@ func (p Plugin) Exec() error {
 
 	if p.BaseImageRegistry != "" {
 		if p.BaseImageUsername == "" {
-			return fmt.Errorf("Username cannot be empty. The base image connector requires authenticated access. Please either use an authenticated connector, or remove the base image connector.")
+			fmt.Printf("Username cannot be empty. The base image connector requires authenticated access. Please either use an authenticated connector, or remove the base image connector.")
 		}
 		if p.BaseImagePassword == "" {
-			return fmt.Errorf("Password cannot be empty. The base image connector requires authenticated access. Please either use an authenticated connector, or remove the base image connector.")
+			fmt.Printf("Password cannot be empty. The base image connector requires authenticated access. Please either use an authenticated connector, or remove the base image connector.")
 		}
 		var baseConnectorLogin Login
 		baseConnectorLogin.Registry = p.BaseImageRegistry
@@ -191,6 +203,10 @@ func (p Plugin) Exec() error {
 			fmt.Println(out)
 			return fmt.Errorf("Error authenticating base connector: exit status 1")
 		}
+	} else if !p.PushOnly {
+		// Skip base image connector warning in push-only mode (not pulling anything)
+		fmt.Println("\033[33mTo ensure consistent and reliable pipeline execution, we recommend setting up a Base Image Connector.\033[0m\n" +
+			"\033[33mWhile optional at this time, configuring it helps prevent failures caused by Docker Hub's rate limits.\033[0m")
 	}
 
 	// login to the Docker registry
@@ -216,6 +232,16 @@ func (p Plugin) Exec() error {
 		}
 	}
 
+	// Enforce mutual exclusivity: push-only and dry-run cannot be used together
+	if p.PushOnly && p.Dryrun {
+		return fmt.Errorf("conflict: push-only and dry-run cannot be used together")
+	}
+
+	// Handle push-only mode if requested
+	if p.PushOnly {
+		return p.pushOnly()
+	}
+
 	if p.Build.Squash && !p.Daemon.Experimental {
 		fmt.Println("Squash build flag is only available when Docker deamon is started with experimental flag. Ignoring...")
 		p.Build.Squash = false
@@ -244,6 +270,14 @@ func (p Plugin) Exec() error {
 
 	cmds = append(cmds, commandBuild(p.Build)) // docker build
 
+	// Validate cosign configuration if present
+	if p.shouldSignWithCosign() {
+		if err := validateCosignConfig(p.Cosign); err != nil {
+			return fmt.Errorf("cosign validation failed: %w", err)
+		}
+		fmt.Println("🔐 Cosign signing enabled - images will be signed after push")
+	}
+
 	for _, tag := range p.Build.Tags {
 		cmds = append(cmds, commandTag(p.Build, tag)) // docker tag
 
@@ -285,6 +319,31 @@ func (p Plugin) Exec() error {
 		}
 	}
 
+	// Handle cosign signing after all commands complete (like artifact generation)
+	if p.shouldSignWithCosign() && !p.Dryrun {
+		// Set up environment variables for cosign
+		os.Setenv("COSIGN_YES", "true")
+
+		if digest, err := getDigest(p.Build.TempTag); err == nil {
+			fmt.Printf("🔐 Found image digest: %s\n", digest)
+			
+			// Sign with digest reference
+			imageRef := fmt.Sprintf("%s@%s", p.Build.Repo, digest)
+			cosignCmd := createCosignCommand(imageRef, p.Cosign)
+			executeCosignCommand(cosignCmd)
+		} else {
+			fmt.Printf("⚠️  WARNING: Could not get image digest for cosign signing: %s\n", err)
+			fmt.Printf("   Falling back to tag-based signing\n")
+			
+			// Fall back to tag-based signing for each tag
+			for _, tag := range p.Build.Tags {
+				imageRef := fmt.Sprintf("%s:%s", p.Build.Repo, tag)
+				cosignCmd := createCosignCommand(imageRef, p.Cosign)
+				executeCosignCommand(cosignCmd)
+			}
+		}
+	}
+
 	// execute cleanup routines in batch mode
 	if p.Cleanup {
 		// clear the slice
@@ -413,8 +472,14 @@ func commandBuild(build Build) *exec.Cmd {
 	for _, arg := range build.ArgsEnv {
 		addProxyValue(&build, arg)
 	}
-	for _, arg := range build.Args {
+	if build.IsMultipleBuildArgs {
-		args = append(args, "--build-arg", arg)
+		for _, arg := range build.ArgsNew {
+			args = append(args, "--build-arg", arg)
+		}
+	} else {
+		for _, arg := range build.Args {
+			args = append(args, "--build-arg", arg)
+		}
 	}
 	for _, host := range build.AddHost {
 		args = append(args, "--add-host", host)
@@ -519,6 +584,10 @@ func addProxyValue(build *Build, key string) {
 		build.Args = append(build.Args, fmt.Sprintf("%s=%s", key, value))
 		build.Args = append(build.Args, fmt.Sprintf("%s=%s", strings.ToUpper(key), value))
 	}
+	if len(value) > 0 && !hasProxyBuildArgNew(build, key) {
+		build.ArgsNew = append(build.ArgsNew, fmt.Sprintf("%s=%s", key, value))
+		build.ArgsNew = append(build.ArgsNew, fmt.Sprintf("%s=%s", strings.ToUpper(key), value))
+	}
 }
 
 // helper function to get a proxy value from the environment.
@@ -546,6 +615,17 @@ func hasProxyBuildArg(build *Build, key string) bool {
 
 	return false
 }
+func hasProxyBuildArgNew(build *Build, key string) bool {
+	keyUpper := strings.ToUpper(key)
+
+	for _, s := range build.ArgsNew {
+		if strings.HasPrefix(s, key) || strings.HasPrefix(s, keyUpper) {
+			return true
+		}
+	}
+
+	return false
+}
 
 // helper function to create the docker tag command.
 func commandTag(build Build, tag string) *exec.Cmd {
@@ -619,6 +699,11 @@ func isCommandRmi(args []string) bool {
 	return len(args) > 2 && args[1] == "rmi"
 }
 
+// helper to check if args match "cosign sign"
+func isCommandCosign(args []string) bool {
+	return len(args) > 1 && args[0] == cosignExe
+}
+
 func commandRmi(tag string) *exec.Cmd {
 	return exec.Command(dockerExe, "rmi", tag)
 }
@@ -655,7 +740,7 @@ func GetDroneDockerExecCmd() string {
 }
 
 func getDigest(buildName string) (string, error) {
-	cmd := exec.Command("docker", "inspect", "--format='{{index .RepoDigests 0}}'", buildName)
+	cmd := exec.Command(dockerExe, "inspect", "--format='{{index .RepoDigests 0}}'", buildName)
 	output, err := cmd.Output()
 	if err != nil {
 		return "", err
@@ -669,3 +754,284 @@ func getDigest(buildName string) (string, error) {
 	}
 	return "", errors.New("unable to fetch digest")
 }
+
+// imageExists checks if an image exists in local daemon
+func imageExists(tag string) bool {
+	cmd := exec.Command(dockerExe, "image", "inspect", tag)
+	return cmd.Run() == nil
+}
+
+// getDigestAfterPush gets digest from a pushed image
+func getDigestAfterPush(tag string) (string, error) {
+	cmd := exec.Command(dockerExe, "inspect", "--format", "{{ index (split (index .RepoDigests 0) \"@\") 1 }}", tag)
+	output, err := cmd.Output()
+	if err != nil {
+		return "", fmt.Errorf("failed to get digest for %s: %w", tag, err)
+	}
+	return strings.TrimSpace(string(output)), nil
+}
+
+// shouldSignWithCosign determines if cosign signing should be performed
+func (p Plugin) shouldSignWithCosign() bool {
+	return p.Cosign.PrivateKey != ""
+}
+
+// validateCosignConfig validates the cosign configuration
+func validateCosignConfig(config CosignConfig) error {
+	if config.PrivateKey == "" {
+		return nil // No cosign config, skip silently
+	}
+
+	// Check if cosign binary is available
+	if _, err := exec.LookPath(cosignExe); err != nil {
+		fmt.Printf("❌ ERROR: cosign binary not found at %s\n", cosignExe)
+		fmt.Println("   Ensure you're using a plugin image that includes cosign")
+		return fmt.Errorf("cosign binary not available: %w", err)
+	}
+
+	// Check if it's trying to use keyless signing
+	if strings.Contains(config.Params, "--oidc") ||
+		strings.Contains(config.Params, "--identity-token") {
+		fmt.Println("⚠️  WARNING: Keyless signing (OIDC) isn't supported yet in this plugin. Use private key signing instead.")
+		return errors.New("keyless signing not supported")
+	}
+
+	// Validate private key format if it's PEM content
+	if strings.HasPrefix(config.PrivateKey, "-----BEGIN") {
+		if !isValidPEMKey(config.PrivateKey) {
+			return errors.New("❌ Invalid private key format. Expected PEM format")
+		}
+
+		// Check encrypted key password requirement
+		if isEncryptedPEMKey(config.PrivateKey) && config.Password == "" {
+			return errors.New("🔐 Encrypted private key requires password. Set PLUGIN_COSIGN_PASSWORD")
+		}
+
+	} else {
+		// File-based key - check if it's accessible (basic check)
+		if _, err := os.Stat(config.PrivateKey); err != nil {
+			fmt.Printf("⚠️  WARNING: Private key file may not be accessible: %s\n", config.PrivateKey)
+			fmt.Println("   This will be verified during signing")
+		}
+	}
+
+	return nil
+}
+
+// isEncryptedPEMKey checks if a PEM key is encrypted
+func isEncryptedPEMKey(pemContent string) bool {
+	return strings.Contains(pemContent, "ENCRYPTED")
+}
+
+// isValidPEMKey performs basic PEM format validation
+func isValidPEMKey(pemContent string) bool {
+	return strings.Contains(pemContent, "-----BEGIN") &&
+		strings.Contains(pemContent, "-----END") &&
+		(strings.Contains(pemContent, "PRIVATE KEY") ||
+			strings.Contains(pemContent, "RSA PRIVATE KEY") ||
+			strings.Contains(pemContent, "EC PRIVATE KEY"))
+}
+
+// createCosignCommand creates a cosign sign command with the given image reference
+func createCosignCommand(imageRef string, cosign CosignConfig) *exec.Cmd {
+	args := []string{"sign", "--yes"}
+	
+	// Handle private key (content vs file path)
+	if strings.HasPrefix(cosign.PrivateKey, "-----BEGIN") {
+		args = append(args, "--key", "env://COSIGN_PRIVATE_KEY")
+		os.Setenv("COSIGN_PRIVATE_KEY", cosign.PrivateKey)
+	} else {
+		args = append(args, "--key", cosign.PrivateKey)
+	}
+	
+	// Set password if provided
+	if cosign.Password != "" {
+		os.Setenv("COSIGN_PASSWORD", cosign.Password)
+	}
+	
+	// Add any extra parameters
+	if cosign.Params != "" {
+		extraArgs := strings.Fields(cosign.Params)
+		args = append(args, extraArgs...)
+	}
+	
+	// Add the image reference to sign
+	args = append(args, imageRef)
+	
+	return exec.Command(cosignExe, args...)
+}
+
+// executeCosignCommand executes the given cosign command and handles errors
+func executeCosignCommand(cmd *exec.Cmd) {
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	fmt.Printf("🚀 Executing: %s %s\n", cmd.Path, strings.Join(cmd.Args[1:], " "))
+
+	if err := cmd.Run(); err != nil {
+		fmt.Printf("⚠️  WARNING: Image signing failed: %s\n", err)
+		fmt.Printf("   Image was pushed successfully but could not be signed\n")
+		fmt.Printf("   This is not fatal - continuing with the build\n")
+	}
+}
+
+// pushOnly handles pushing images without building them
+func (p Plugin) pushOnly() error {
+	// Check if source image is specified
+	sourceImageName := p.SourceImage
+	var sourceTags []string
+
+	if sourceImageName == "" {
+		// If no source image specified, use the repo and first tag
+		fmt.Println("source_image not provided, using repo and tag value")
+		sourceImageName = p.Build.Repo
+		sourceTags = p.Build.Tags
+	} else {
+		// If source image is specified, check if it has a tag
+		lastColonIndex := strings.LastIndex(sourceImageName, ":")
+		if lastColonIndex > 0 && lastColonIndex < len(sourceImageName) {
+			// Check if there's a slash after the last colon (indicating it's a port, not a tag)
+			// For example: registry:5000/image (has slash after colon - port not tag)
+			// vs image:tag (no slash after colon - it's a tag)
+			if strings.LastIndex(sourceImageName, "/") > lastColonIndex {
+				// The last colon is part of the registry:port, not a tag separator
+				sourceTags = []string{"latest"}
+			} else {
+				// The last colon separates the tag
+				tag := sourceImageName[lastColonIndex+1:]
+				sourceImageName = sourceImageName[:lastColonIndex]
+
+				if tag == "" {
+					fmt.Printf("No tag specified in source image (or empty tag). Using 'latest' as the default tag.\n")
+					tag = "latest"
+				}
+				sourceTags = []string{tag}
+			}
+		} else {
+			// Default to "latest" if no tag specified
+			sourceTags = []string{"latest"}
+		}
+		fmt.Printf("Using source image: %s with tag(s): %s\n", sourceImageName, strings.Join(sourceTags, ", "))
+	}
+
+	// For each source tag and target tag combination
+	var digest string
+	var firstPushedImage string
+
+	for _, sourceTag := range sourceTags {
+		sourceFullImageName := fmt.Sprintf("%s:%s", sourceImageName, sourceTag)
+
+		// Check if the source image exists in local daemon
+		if !imageExists(sourceFullImageName) {
+			fmt.Printf("Warning: Source image %s not found\n", sourceFullImageName)
+			// Continue to the next source tag if available, otherwise return error
+			if len(sourceTags) > 1 {
+				continue
+			}
+			return fmt.Errorf("source image %s not found, cannot push", sourceFullImageName)
+		}
+
+		// For each target tag, tag and push
+		for _, targetTag := range p.Build.Tags {
+			targetFullImageName := fmt.Sprintf("%s:%s", p.Build.Repo, targetTag)
+
+			// Skip if source and target are identical
+			if sourceFullImageName == targetFullImageName {
+				fmt.Printf("Source and target image names are identical: %s\n", sourceFullImageName)
+			} else {
+				// Tag the source image with the target name
+				fmt.Printf("Tagging %s as %s\n", sourceFullImageName, targetFullImageName)
+				tagCmd := exec.Command(dockerExe, "tag", sourceFullImageName, targetFullImageName)
+				tagCmd.Stdout = os.Stdout
+				tagCmd.Stderr = os.Stderr
+				trace(tagCmd)
+				if err := tagCmd.Run(); err != nil {
+					return fmt.Errorf("failed to tag image %s as %s: %w", sourceFullImageName, targetFullImageName, err)
+				}
+			}
+		}
+	}
+
+	// Push all target images
+	for _, tag := range p.Build.Tags {
+		fullImageName := fmt.Sprintf("%s:%s", p.Build.Repo, tag)
+
+		// Check if image exists in local daemon
+		if !imageExists(fullImageName) {
+			return fmt.Errorf("image %s not found, cannot push", fullImageName)
+		}
+
+		// Push image
+		fmt.Println("Pushing image:", fullImageName)
+		pushCmd := commandPush(p.Build, tag)
+		pushCmd.Stdout = os.Stdout
+		pushCmd.Stderr = os.Stderr
+		trace(pushCmd)
+		if err := pushCmd.Run(); err != nil {
+			return fmt.Errorf("failed to push image %s: %w", fullImageName, err)
+		}
+
+		// Track the first pushed image for card generation
+		if firstPushedImage == "" {
+			firstPushedImage = fullImageName
+		}
+
+		// Get the digest after push (we only need one)
+		if digest == "" {
+			d, err := getDigestAfterPush(fullImageName)
+			if err == nil {
+				digest = d
+			} else {
+				fmt.Printf("Warning: Could not get digest for %s: %v\n", fullImageName, err)
+			}
+		}
+	}
+
+	// Output the adaptive card
+	if firstPushedImage != "" {
+		if err := p.writeCardForImage(firstPushedImage); err != nil {
+			fmt.Printf("Could not create adaptive card. %s\n", err)
+		}
+	}
+
+	// Write to artifact file
+	if p.ArtifactFile != "" && digest != "" {
+		if err := drone.WritePluginArtifactFile(
+			p.Daemon.RegistryType,
+			p.ArtifactFile,
+			p.Daemon.Registry,
+			p.Build.Repo,
+			digest,
+			p.Build.Tags,
+		); err != nil {
+			fmt.Printf("Failed to write plugin artifact file at path: %s with error: %s\n",
+				p.ArtifactFile, err)
+		}
+	}
+
+	// Handle cosign signing after push
+	if p.shouldSignWithCosign() {
+		// Set up environment variables for cosign
+		os.Setenv("COSIGN_YES", "true")
+
+		if digest != "" {
+			fmt.Printf("🔐 Found image digest: %s\n", digest)
+
+			// Sign with digest reference
+			imageRef := fmt.Sprintf("%s@%s", p.Build.Repo, digest)
+			cosignCmd := createCosignCommand(imageRef, p.Cosign)
+			executeCosignCommand(cosignCmd)
+		} else {
+			fmt.Printf("⚠️  WARNING: Could not get image digest for cosign signing\n")
+			fmt.Printf("   Falling back to tag-based signing\n")
+
+			// Fall back to tag-based signing for each tag
+			for _, tag := range p.Build.Tags {
+				imageRef := fmt.Sprintf("%s:%s", p.Build.Repo, tag)
+				cosignCmd := createCosignCommand(imageRef, p.Cosign)
+				executeCosignCommand(cosignCmd)
+			}
+		}
+	}
+
+	return nil
+}

docker/docker/Dockerfile.linux.amd64

@@ -1,6 +1,10 @@
-FROM docker:20.10.14-dind
+FROM docker:28.1.1-dind
 
 ENV DOCKER_HOST=unix:///var/run/docker.sock
 
+# Install cosign for container image signing
+RUN wget -O /usr/local/bin/cosign https://github.com/sigstore/cosign/releases/download/v2.5.3/cosign-linux-amd64 \
+    && chmod +x /usr/local/bin/cosign
+
 ADD release/linux/amd64/drone-docker /bin/
 ENTRYPOINT ["/usr/local/bin/dockerd-entrypoint.sh", "/bin/drone-docker"]

docker/docker/Dockerfile.linux.arm64

@@ -1,6 +1,10 @@
-FROM arm64v8/docker:20.10.14-dind
+FROM arm64v8/docker:28.1.1-dind
 
 ENV DOCKER_HOST=unix:///var/run/docker.sock
 
+# Install cosign for container image signing
+RUN wget -O /usr/local/bin/cosign https://github.com/sigstore/cosign/releases/download/v2.5.3/cosign-linux-arm64 \
+    && chmod +x /usr/local/bin/cosign
+
 ADD release/linux/arm64/drone-docker /bin/
 ENTRYPOINT ["/usr/local/bin/dockerd-entrypoint.sh", "/bin/drone-docker"]

docker/docker/Dockerfile.windows.amd64.1809

@@ -24,6 +24,10 @@ LABEL maintainer="Drone.IO Community <drone-dev@googlegroups.com>" `
   org.label-schema.schema-version="1.0"
 
 RUN mkdir C:\bin
+
+# Install cosign for container image signing
+ADD https://github.com/sigstore/cosign/releases/download/v2.5.3/cosign-windows-amd64.exe C:/bin/cosign.exe
+
 COPY --from=download /windows/system32/netapi32.dll /windows/system32/netapi32.dll
 COPY --from=download /app/docker.exe C:/bin/docker.exe
 ADD release/windows/amd64/drone-docker.exe C:/bin/drone-docker.exe

docker/docker/Dockerfile.windows.amd64.ltsc2022

@@ -22,6 +22,10 @@ LABEL maintainer="Drone.IO Community <drone-dev@googlegroups.com>" `
   org.label-schema.schema-version="1.0"
 
 RUN mkdir C:\bin
+
+# Install cosign for container image signing
+ADD https://github.com/sigstore/cosign/releases/download/v2.5.3/cosign-windows-amd64.exe C:/bin/cosign.exe
+
 COPY --from=download /windows/system32/netapi32.dll /windows/system32/netapi32.dll
 COPY --from=download /app/docker.exe C:/bin/docker.exe
 ADD release/windows/amd64/drone-docker.exe C:/bin/drone-docker.exe

go.mod

@@ -1,6 +1,8 @@
 module github.com/drone-plugins/drone-docker
 
 require (
+	github.com/Azure/azure-sdk-for-go/sdk/azcore v1.17.1
+	github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.8.2
 	github.com/aws/aws-sdk-go v1.26.7
 	github.com/coreos/go-semver v0.3.0
 	github.com/dchest/uniuri v1.2.0
@@ -8,33 +10,37 @@ require (
 	github.com/drone/drone-go v1.7.1
 	github.com/inhies/go-bytesize v0.0.0-20210819104631-275770b98743
 	github.com/joho/godotenv v1.3.0
+	github.com/pkg/errors v0.9.1
 	github.com/sirupsen/logrus v1.9.0
-	github.com/stretchr/testify v1.8.1
+	github.com/stretchr/testify v1.10.0
 	github.com/urfave/cli v1.22.2
-	golang.org/x/oauth2 v0.13.0
+	golang.org/x/oauth2 v0.27.0
 	google.golang.org/api v0.146.0
 )
 
 require (
-	cloud.google.com/go/compute v1.23.1 // indirect
+	cloud.google.com/go/compute/metadata v0.3.0 // indirect
-	cloud.google.com/go/compute/metadata v0.2.3 // indirect
+	github.com/Azure/azure-sdk-for-go/sdk/internal v1.10.0 // indirect
+	github.com/AzureAD/microsoft-authentication-library-for-go v1.3.3 // indirect
 	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/golang-jwt/jwt/v5 v5.2.1 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/google/s2a-go v0.1.7 // indirect
-	github.com/google/uuid v1.3.1 // indirect
+	github.com/google/uuid v1.6.0 // indirect
 	github.com/googleapis/enterprise-certificate-proxy v0.3.1 // indirect
 	github.com/googleapis/gax-go/v2 v2.12.0 // indirect
 	github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af // indirect
+	github.com/kylelemons/godebug v1.1.0 // indirect
+	github.com/pkg/browser v0.0.0-20240102092130-5ac0b6a4141c // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect
 	go.opencensus.io v0.24.0 // indirect
-	golang.org/x/crypto v0.14.0 // indirect
+	golang.org/x/crypto v0.36.0 // indirect
-	golang.org/x/net v0.17.0 // indirect
+	golang.org/x/net v0.37.0 // indirect
-	golang.org/x/sys v0.13.0 // indirect
+	golang.org/x/sys v0.31.0 // indirect
-	golang.org/x/text v0.13.0 // indirect
+	golang.org/x/text v0.23.0 // indirect
-	google.golang.org/appengine v1.6.8 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20231016165738-49dd2c1f3d0b // indirect
 	google.golang.org/grpc v1.59.0 // indirect
 	google.golang.org/protobuf v1.31.0 // indirect
@@ -42,4 +48,6 @@ require (
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )
 
-go 1.22.4
+go 1.23.0
+
+toolchain go1.23.7

go.sum

@@ -1,13 +1,25 @@
 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
-cloud.google.com/go/compute v1.23.1 h1:V97tBoDaZHb6leicZ1G6DLK2BAaZLJ/7+9BB/En3hR0=
+cloud.google.com/go/compute/metadata v0.3.0 h1:Tz+eQXMEqDIKRsmY3cHTL6FVaynIjX2QxYC4trgAKZc=
-cloud.google.com/go/compute v1.23.1/go.mod h1:CqB3xpmPKKt3OJpW2ndFIXnA9A4xAy/F3Xp1ixncW78=
+cloud.google.com/go/compute/metadata v0.3.0/go.mod h1:zFmK7XCadkQkj6TtorcaGlCW1hT1fIilQDwofLpJ20k=
-cloud.google.com/go/compute/metadata v0.2.3 h1:mg4jlk7mCAj6xXp9UJ4fjI9VUI5rubuGBW5aJ7UnBMY=
-cloud.google.com/go/compute/metadata v0.2.3/go.mod h1:VAV5nSsACxMJvgaAuX6Pk2AawlZn8kiOGuCv6gTkwuA=
 github.com/99designs/httpsignatures-go v0.0.0-20170731043157-88528bf4ca7e/go.mod h1:Xa6lInWHNQnuWoF0YPSsx+INFA9qk7/7pTjwb3PInkY=
+github.com/Azure/azure-sdk-for-go/sdk/azcore v1.17.1 h1:DSDNVxqkoXJiko6x8a90zidoYqnYYa6c1MTzDKzKkTo=
+github.com/Azure/azure-sdk-for-go/sdk/azcore v1.17.1/go.mod h1:zGqV2R4Cr/k8Uye5w+dgQ06WJtEcbQG/8J7BB6hnCr4=
+github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.8.2 h1:F0gBpfdPLGsw+nsgk6aqqkZS1jiixa5WwFe3fk/T3Ys=
+github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.8.2/go.mod h1:SqINnQ9lVVdRlyC8cd1lCI0SdX4n2paeABd2K8ggfnE=
+github.com/Azure/azure-sdk-for-go/sdk/azidentity/cache v0.3.2 h1:yz1bePFlP5Vws5+8ez6T3HWXPmwOK7Yvq8QxDBD3SKY=
+github.com/Azure/azure-sdk-for-go/sdk/azidentity/cache v0.3.2/go.mod h1:Pa9ZNPuoNu/GztvBSKk9J1cDJW6vk/n0zLtV4mgd8N8=
+github.com/Azure/azure-sdk-for-go/sdk/internal v1.10.0 h1:ywEEhmNahHBihViHepv3xPBn1663uRv2t2q/ESv9seY=
+github.com/Azure/azure-sdk-for-go/sdk/internal v1.10.0/go.mod h1:iZDifYGJTIgIIkYRNWPENUnqx6bJ2xnSDFI2tjwZNuY=
+github.com/AzureAD/microsoft-authentication-extensions-for-go/cache v0.1.1 h1:WJTmL004Abzc5wDB5VtZG2PJk5ndYDgVacGqfirKxjM=
+github.com/AzureAD/microsoft-authentication-extensions-for-go/cache v0.1.1/go.mod h1:tCcJZ0uHAmvjsVYzEFivsRTN00oz5BEsRgQHu5JZ9WE=
+github.com/AzureAD/microsoft-authentication-library-for-go v1.3.3 h1:H5xDQaE3XowWfhZRUpnfC+rGZMEVoSiji+b+/HFAPU4=
+github.com/AzureAD/microsoft-authentication-library-for-go v1.3.3/go.mod h1:wP83P5OoQ5p6ip3ScPr0BAq0BvuPAvacpEuSzyouqAI=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/aws/aws-sdk-go v1.26.7 h1:ObjEnmzvSdYy8KVd3me7v/UMyCn81inLy2SyoIPoBkg=
 github.com/aws/aws-sdk-go v1.26.7/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
+github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
+github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDkc90ppPyw=
 github.com/cncf/udpa/go v0.0.0-20191209042840-269d4d468f6f/go.mod h1:M8M6+tZqaGXZJjfX53e64911xZQV5JYwmTeXPW+k8Sc=
 github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
@@ -20,6 +32,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dchest/uniuri v1.2.0 h1:koIcOUdrTIivZgSLhHQvKgqdWZq5d7KdMEWF1Ud6+5g=
 github.com/dchest/uniuri v1.2.0/go.mod h1:fSzm4SLHzNZvWLvWJew423PhAzkpNQYq+uNLq4kxhkY=
+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/rVNCu3HqELle0jiPLLBs70cWOduZpkS1E78=
+github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
 github.com/drone-plugins/drone-plugin-lib v0.4.1 h1:47rZlmcMpr1hSp+6Gl+1Z4t+efi/gMQU3lxukC1Yg64=
 github.com/drone-plugins/drone-plugin-lib v0.4.1/go.mod h1:KwCu92jFjHV3xv2hu5Qg/8zBNvGwbhoJDQw/EwnTvoM=
 github.com/drone/drone-go v1.7.1 h1:ZX+3Rs8YHUSUQ5mkuMLmm1zr1ttiiE2YGNxF3AnyDKw=
@@ -28,6 +42,8 @@ github.com/envoyproxy/go-control-plane v0.9.0/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymF
 github.com/envoyproxy/go-control-plane v0.9.1-0.20191026205805-5f8ba28d4473/go.mod h1:YTl/9mNaCwkRvm6d1a2C3ymFceY/DCBVvsKhRF0iEA4=
 github.com/envoyproxy/go-control-plane v0.9.4/go.mod h1:6rpuAdCZL397s3pYoYcLgu1mIlRU8Am5FuJP05cCM98=
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
+github.com/golang-jwt/jwt/v5 v5.2.1 h1:OuVbFODueb089Lh128TAcimifWaLhJwVflnrgM17wHk=
+github.com/golang-jwt/jwt/v5 v5.2.1/go.mod h1:pqrtFR0X4osieyHYxtmOUWsAWrfe1Q5UVIyoH402zdk=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/groupcache v0.0.0-20200121045136-8c9f03a8e57e/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
 github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da h1:oI5xCqsCo564l8iNU+DwB5epxmsaqB+rhGL0m5jtYqE=
@@ -43,7 +59,6 @@ github.com/golang/protobuf v1.4.0/go.mod h1:jodUvKwWbYaEsadDk5Fwe5c77LiNKVO9IDvq
 github.com/golang/protobuf v1.4.1/go.mod h1:U8fpvMrcmy5pZrNK1lt4xCsGvpyWQ/VVv6QDs8UjoX8=
 github.com/golang/protobuf v1.4.3/go.mod h1:oDoupMAO8OvCJWAcko0GGGIgR6R6ocIYbsSw735rRwI=
 github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
-github.com/golang/protobuf v1.5.2/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
 github.com/golang/protobuf v1.5.3 h1:KhyjKVUg7Usr/dYsdSqoFveMYd5ko72D+zANwlG1mmg=
 github.com/golang/protobuf v1.5.3/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
@@ -58,8 +73,8 @@ github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeN
 github.com/google/s2a-go v0.1.7 h1:60BLSyTrOV4/haCDW4zb1guZItoSq8foHCXrAnjBo/o=
 github.com/google/s2a-go v0.1.7/go.mod h1:50CgR4k1jNlWBu4UfS4AcfhVe1r6pdZPygJ3R8F0Qdw=
 github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
-github.com/google/uuid v1.3.1 h1:KjJaJ9iWZ3jOFZIf1Lqf4laDRCasjl0BCmnEGxkdLb4=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
-github.com/google/uuid v1.3.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/googleapis/enterprise-certificate-proxy v0.3.1 h1:SBWmZhjUDRorQxrN0nwzf+AHBxnbFjViHQS4P0yVpmQ=
 github.com/googleapis/enterprise-certificate-proxy v0.3.1/go.mod h1:VLSiSSBs/ksPL8kq3OBOQ6WRI2QnaFynd1DCjZ62+V0=
 github.com/googleapis/gax-go/v2 v2.12.0 h1:A+gCJKdRfqXkr+BIRGtZLibNXf0m1f9E4HG56etFpas=
@@ -70,9 +85,25 @@ github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af h1:pmfjZENx5i
 github.com/jmespath/go-jmespath v0.0.0-20180206201540-c2b33e8439af/go.mod h1:Nht3zPeWKUH0NzdCt2Blrr5ys8VGpn0CEB0cQHVjt7k=
 github.com/joho/godotenv v1.3.0 h1:Zjp+RcGpHhGlrMbJzXTrZZPrWj+1vfm90La1wgB6Bhc=
 github.com/joho/godotenv v1.3.0/go.mod h1:7hK45KPybAkOC6peb+G5yklZfMxEjkZhHbwpqxOKXbg=
+github.com/keybase/go-keychain v0.0.0-20231219164618-57a3676c3af6 h1:IsMZxCuZqKuao2vNdfD82fjjgPLfyHLpR41Z88viRWs=
+github.com/keybase/go-keychain v0.0.0-20231219164618-57a3676c3af6/go.mod h1:3VeWNIJaW+O5xpRQbPp0Ybqu1vJd/pm7s2F473HRrkw=
+github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
+github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
+github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
+github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
+github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=
+github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
+github.com/pkg/browser v0.0.0-20240102092130-5ac0b6a4141c h1:+mdjkGKdHQG3305AYmdv1U2eRNDiU2ErMBj1gwrq8eQ=
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 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prometheus/client_model v0.0.0-20190812154241-14fe0d1b01d4/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
+github.com/redis/go-redis/v9 v9.7.0 h1:HhLSs+B6O021gwzl+locl0zEDnyNkxMtf/Z3NNBMa9E=
+github.com/redis/go-redis/v9 v9.7.0/go.mod h1:f6zhXITC7JUJIlPEiBOTXxJgPLdZcA93GewI7inzyWw=
+github.com/rogpeppe/go-internal v1.12.0 h1:exVL4IDcn6na9z1rAb56Vxr+CgyK3nn3O+epU5NdKM8=
+github.com/rogpeppe/go-internal v1.12.0/go.mod h1:E+RYuTGaKKdloAfM02xzb0FW3Paa99yedzYV+kq4uf4=
 github.com/russross/blackfriday/v2 v2.0.1/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
@@ -85,77 +116,59 @@ github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpE
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
-github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 github.com/urfave/cli v1.22.2 h1:gsqYFH8bb9ekPA12kRo0hfjngWQjkJPlN9R0N78BoUo=
 github.com/urfave/cli v1.22.2/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=
-github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 go.opencensus.io v0.24.0 h1:y73uSU6J157QMP2kn2r30vwW1A2W2WFwSCGnAVxeaD0=
 go.opencensus.io v0.24.0/go.mod h1:vNK8G9p7aAivkbmorf4v+7Hgx+Zs0yY+0fOtgBfjQKo=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
-golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
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-golang.org/x/crypto v0.14.0 h1:wBqGXzWJW6m1XrIKlAH0Hs1JJ7+9KBwnIO8v66Q9cHc=
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-golang.org/x/crypto v0.14.0/go.mod h1:MVFd36DqK4CsrnJYDkBA3VC4m2GkXAM0PvzMCn4JQf4=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3/go.mod h1:UVdnD1Gm6xHRNCYTkRU2/jEulfH38KcIWyp/GAMgvoE=
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-golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
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-golang.org/x/net v0.17.0/go.mod h1:NxSsAGuq816PNPmqtQdLE42eU2Fs7NoRIZrHJAlaCOE=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
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 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190114222345-bf090417da8b/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190226205152-f727befe758c/go.mod h1:9Yl7xja0Znq3iFh3HoIrodX9oNMXvdceNzlUR8zjMvY=
 golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
 golang.org/x/tools v0.0.0-20190524140312-2c0ae7006135/go.mod h1:RgjU9mgBXZiqYHBnxXauZ1Gv1EHHAz9KjViQ78xBX0Q=
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-golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
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 google.golang.org/api v0.146.0/go.mod h1:OARJqIfoYjXJj4C1AiBSXYZt03qsoz8FQYU6fBEfrHM=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
 google.golang.org/appengine v1.4.0/go.mod h1:xpcJRLb0r/rnEns0DIKYYv+WjYCduHsrkT7/EB5XEv4=
-google.golang.org/appengine v1.6.8 h1:IhEN5q69dyKagZPYMSdIjS2HqprW324FRQZJcGqPAsM=
-google.golang.org/appengine v1.6.8/go.mod h1:1jJ3jBArFh5pcgW8gCtRJnepW8FzD1V44FJffLiz/Ds=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/genproto v0.0.0-20190819201941-24fa4b261c55/go.mod h1:DMBHOl98Agz4BDEuKkezgsaosCRResVns1a3J2ZsMNc=
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@@ -185,8 +198,9 @@ google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp0
 google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
 google.golang.org/protobuf v1.31.0 h1:g0LDEJHgrBl9N9r17Ru3sqWhkIx2NB67okBHPwC7hs8=
 google.golang.org/protobuf v1.31.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.8 h1:obN1ZagJSUGI0Ek/LBmuj4SNLPfIny3KsKFopxRdj10=
 gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

internal/azure/tokenutil.go

@@ -0,0 +1,75 @@
+package azure
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+)
+
+const DefaultResource = "https://management.azure.com/"
+const defaultAuthorityHost = "https://login.microsoftonline.com"
+const defaultHTTPTimeout = 30 * time.Second
+
+// GetAADAccessTokenViaClientAssertion exchanges an external OIDC ID token for an Azure AD access token
+
+func GetAADAccessTokenViaClientAssertion(ctx context.Context, tenantID, clientID, oidcToken, authorityHost string) (string, error) {
+    resource := DefaultResource
+
+	form := url.Values{
+		"client_id":             {clientID},
+		"scope":                 {resource + ".default"},
+		"grant_type":            {"client_credentials"},
+		"client_assertion_type": {"urn:ietf:params:oauth:client-assertion-type:jwt-bearer"},
+		"client_assertion":      {oidcToken},
+	}
+
+	base := authorityHost
+	if strings.TrimSpace(base) == "" {
+		base = defaultAuthorityHost
+	}
+	base = strings.TrimRight(base, "/")
+	endpoint := fmt.Sprintf("%s/%s/oauth2/v2.0/token", base, tenantID)
+
+	client := &http.Client{Timeout: defaultHTTPTimeout}
+	req, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint, strings.NewReader(form.Encode()))
+	if err != nil {
+		return "", err
+	}
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	req.Header.Set("Accept", "application/json")
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return "", err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		var aadErr struct {
+			Error            string `json:"error"`
+			ErrorDescription string `json:"error_description"`
+		}
+		limited := io.LimitedReader{R: resp.Body, N: 4096}
+		_ = json.NewDecoder(&limited).Decode(&aadErr)
+		if aadErr.Error != "" {
+			return "", fmt.Errorf("AAD token request failed: status=%d, error=%s", resp.StatusCode, aadErr.Error)
+		}
+		return "", fmt.Errorf("AAD token request failed: status=%d", resp.StatusCode)
+	}
+	var payload struct {
+		AccessToken string `json:"access_token"`
+		TokenType   string `json:"token_type"`
+		ExpiresIn   int    `json:"expires_in"`
+	}
+	if err := json.NewDecoder(resp.Body).Decode(&payload); err != nil {
+		return "", err
+	}
+	if payload.AccessToken == "" {
+		return "", fmt.Errorf("AAD token response missing access_token")
+	}
+	return payload.AccessToken, nil
+}

internal/azure/tokenutil_test.go

@@ -0,0 +1,104 @@
+package azure
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+func TestGetAADAccessTokenViaClientAssertion_Success(t *testing.T) {
+
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != http.MethodPost {
+			t.Fatalf("expected POST, got %s", r.Method)
+		}
+		if ct := r.Header.Get("Content-Type"); !strings.Contains(ct, "application/x-www-form-urlencoded") {
+			t.Fatalf("expected form content-type, got %s", ct)
+		}
+		if err := r.ParseForm(); err != nil {
+			t.Fatalf("failed parsing form: %v", err)
+		}
+		assertEq(t, r.Form.Get("client_id"), "client")
+		assertEq(t, r.Form.Get("grant_type"), "client_credentials")
+		assertEq(t, r.Form.Get("client_assertion_type"), "urn:ietf:params:oauth:client-assertion-type:jwt-bearer")
+		assertEq(t, r.Form.Get("client_assertion"), "idtoken")
+		assertEq(t, r.Form.Get("scope"), DefaultResource+".default")
+
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		_, _ = w.Write([]byte(`{"access_token":"AT","token_type":"Bearer","expires_in":3600}`))
+	}))
+	defer ts.Close()
+
+	tok, err := GetAADAccessTokenViaClientAssertion(context.Background(), "tenant", "client", "idtoken", ts.URL)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if tok != "AT" {
+		t.Fatalf("expected access token AT, got %q", tok)
+	}
+}
+
+func TestGetAADAccessTokenViaClientAssertion_400WithErrorField(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusBadRequest)
+		_, _ = w.Write([]byte(`{"error":"invalid_client","error_description":"bad"}`))
+	}))
+	defer ts.Close()
+
+	_, err := GetAADAccessTokenViaClientAssertion(context.Background(), "tenant", "client", "idtoken", ts.URL)
+	if err == nil || !strings.Contains(err.Error(), "status=400") || !strings.Contains(err.Error(), "invalid_client") {
+		t.Fatalf("expected 400 with invalid_client error, got %v", err)
+	}
+}
+
+func TestGetAADAccessTokenViaClientAssertion_400WithoutErrorField(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusBadRequest)
+		_, _ = w.Write([]byte("{}"))
+	}))
+	defer ts.Close()
+
+	_, err := GetAADAccessTokenViaClientAssertion(context.Background(), "tenant", "client", "idtoken", ts.URL)
+	if err == nil || !strings.Contains(err.Error(), "status=400") {
+		t.Fatalf("expected 400 error, got %v", err)
+	}
+}
+
+func TestGetAADAccessTokenViaClientAssertion_MalformedJSON(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.WriteHeader(http.StatusOK)
+		_, _ = w.Write([]byte("not-json"))
+	}))
+	defer ts.Close()
+
+	_, err := GetAADAccessTokenViaClientAssertion(context.Background(), "tenant", "client", "idtoken", ts.URL)
+	if err == nil {
+		t.Fatalf("expected JSON decode error, got nil")
+	}
+}
+
+func TestGetAADAccessTokenViaClientAssertion_MissingAccessToken(t *testing.T) {
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		_, _ = w.Write([]byte(`{"token_type":"Bearer","expires_in":3600}`))
+	}))
+	defer ts.Close()
+
+	_, err := GetAADAccessTokenViaClientAssertion(context.Background(), "tenant", "client", "idtoken", ts.URL)
+	if err == nil || !strings.Contains(err.Error(), "missing access_token") {
+		t.Fatalf("expected missing access_token error, got %v", err)
+	}
+}
+
+func assertEq(t *testing.T, got, want string) {
+	t.Helper()
+	if got != want {
+		t.Fatalf("mismatch: got=%q want=%q", got, want)
+	}
+}
+