Can I use consign to verify local images？

[neblen]

Question

I pull images from images registry and I want verify these local images.Can I use cosign to verify local images？ These images have been singed by cosign in remote registry.

[cpanato]

you can check the image before pulling for example:

I have no images locally

$ docker images
REPOSITORY   TAG       IMAGE ID   CREATED   SIZE

I want to check an image

$ COSIGN_EXPERIMENTAL=1 cosign verify gcr.io/projectsigstore/cosign:v1.6.0

$ COSIGN_EXPERIMENTAL=1 cosign verify gcr.io/projectsigstore/cosign:v1.6.0

Verification for gcr.io/projectsigstore/cosign:v1.6.0 --
The following checks were performed on each of these signatures:
  - The cosign claims were validated
  - Existence of the claims in the transparency log was verified offline
  - Any certificates were verified against the Fulcio roots.

[{"critical":{"identity":{"docker-reference":"gcr.io/projectsigstore/cosign"},"image":{"docker-manifest-digest":"sha256:b667002156c4bf9fedd9273f689b800bb5c341660e710e3bbac981c9795423d9"},"type":"cosign container image signature"},"optional":{"Bundle":{"SignedEntryTimestamp":"MEUCIQDKOjHLFQDrOfI0FGxaOUVcrvuh639SwV+4rhim2cg3ZAIgctpg49VMRpvKJ5ENfLuma6vcfaoxaWa6i8GaRhF/HLo=","Payload":{"body":"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","integratedTime":1646381571,"logIndex":1556936,"logID":"c0d23d6ad406973f9559f3ba2d1ca01f84147d8ffc5b8445c224f98b9591801d"}},"GIT_HASH":"4b2c3c0c8ee97f31b9dac3859b40e0a48b8648ee","GIT_VERSION":"v1.6.0","Issuer":"https://accounts.google.com","Subject":"[email protected]"}}]

then i can pull the image if I want

[neblen]

Thank you for your reply! I konw this usage.But when someone modify the local images,I can't verify these local images.If I am worried about these local images safety,I need to delete these images and pull images again from remote registry.

[cpanato]

ahh, you can use the flag --local-image but for that, you need to have the image saved using cosign save

[neblen]

@cpanato Thank you very much.When I use the command cosign save，there are some problems.

./cosign sign -key cosign.key dev.harbor.com/test/hello-world:v1
WARNING: the flag -key is deprecated and will be removed in a future release. Please use the flag --key.
an error occurred: no provider found for that key reference, will try to load key from disk...
Enter password for private key: Pushing signature to: dev.harbor.com/test/hello-world

[user@harbor-user-2-5 cosign]# ./cosign save dev.harbor.com/test/hello-world:v1 --dir=/home
Error: getting signatures: GET https://dev.harbor.com/v2/test/hello-world/manifests/sha256-f54a58bc1aac5ea1a25d796ae155dc228b3f0e11d046ae276b39c4bf2f13d8c4.sig: PROJECTPOLICYVIOLATION: The image is not signed in Cosign.
main.go:46: error during command execution: getting signatures: GET https://dev.harbor.com/v2/test/hello-world/manifests/sha256-f54a58bc1aac5ea1a25d796aexxxxxxc228b3f0e11d046ae276b39c4bf2xxxxxxx.sig: PROJECTPOLICYVIOLATION: The image is not signed in Cosign.

Could you please provide some usage examples? Thank you so much!

[adammfrank]

@cpanato @neblen What do you do with a saved local image once it's been verified? How do you now run that image? Does it need to be sent back to the registry first?

[cpanato]

sorry for the delay, missed this notification :(

i've run that using:

$ cosign version
  ______   ______        _______. __    _______ .__   __.
 /      | /  __  \      /       ||  |  /  _____||  \ |  |
|  ,----'|  |  |  |    |   (----`|  | |  |  __  |   \|  |
|  |     |  |  |  |     \   \    |  | |  | |_ | |  . `  |
|  `----.|  `--'  | .----)   |   |  | |  |__| | |  |\   |
 \______| \______/  |_______/    |__|  \______| |__| \__|
cosign: A tool for Container Signing, Verification and Storage in an OCI registry.

GitVersion:    v1.8.0
GitCommit:     9ef6b207218572b3257a5b4251418d75569baaae
GitTreeState:  clean
BuildDate:     2022-04-27T13:40:34Z
GoVersion:     go1.17.9
Compiler:      gc
Platform:      darwin/arm64

save:

$ cosign save ghcr.io/sigstore/cosign/cosign:v1.8.0 --dir=/tmp

verify:

$ export COSIGN_EXPERIMENTAL=true
$ cosign verify --local-image /tmp

Verification for /tmp --
The following checks were performed on each of these signatures:
  - The cosign claims were validated
  - Existence of the claims in the transparency log was verified offline
  - Any certificates were verified against the Fulcio roots.

[{"critical":{"identity":{"docker-reference":"gcr.io/projectsigstore/cosign"},"image":{"docker-manifest-digest":"sha256:12b4d428529654c95a7550a936cbb5c6fe93a046ea7454676cb6fb0ce566d78c"},"type":"cosign container image signature"},"optional":{"Bundle":{"SignedEntryTimestamp":"MEUCIQDHwZnXU3V2fZHMn2RdDZewIemjMOIUlMWnJYfdw3AqZAIgfDqV5azShQfNzwSEHw5XJ81ipI0nbRxmsQAkeEFkDiM=","Payload":{"body":"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","integratedTime":1651068443,"logIndex":2163451,"logID":"c0d23d6ad406973f9559f3ba2d1ca01f84147d8ffc5b8445c224f98b9591801d"}},"GIT_HASH":"9ef6b207218572b3257a5b4251418d75569baaae","GIT_VERSION":"v1.8.0","Issuer":"https://accounts.google.com","Subject":"[email protected]"}}]

[github-actions[bot]]

This issue is stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 5 days.

[github-actions[bot]]

This issue was closed because it has been stalled for 5 days with no activity.