Add support for SigningConfig in sign/attest

[haydentherapper]

Summary

This will indirectly add support for signing with Rekor v2, since signing will be handled by sigstore-go rather than Cosign.

This also brings sign/attest up to par with the recent changes to sign-blob/attest-blob, including signing with a key and providing a path to a trusted root when providing a signing config to verify after signing.

This feature is gated behind one of two signing config flags, which in a later version of Cosign will be flipped to on by default. Once this is the default, we'll be able to refactor the core signing and verification logic in Cosign, largely replacing it with sigstore-go.

Fixes #4324

Release Note

Documentation

[codecov]

Codecov Report

❌ Patch coverage is 11.38393% with 397 lines in your changes missing coverage. Please review.
✅ Project coverage is 33.88%. Comparing base (2ef6022) to head (ee986f2).
⚠️ Report is 491 commits behind head on main.

Files with missing lines	Patch %	Lines
cmd/cosign/cli/sign/sign.go	2.24%	87 Missing ⚠️
cmd/cosign/cli/attest/attest.go	0.00%	69 Missing ⚠️
cmd/cosign/cli/attest.go	0.00%	51 Missing ⚠️
cmd/cosign/cli/attest/attest_blob.go	2.22%	43 Missing and 1 partial ⚠️
cmd/cosign/cli/sign/sign_blob.go	2.22%	43 Missing and 1 partial ⚠️
cmd/cosign/cli/attest_blob.go	0.00%	29 Missing ⚠️
cmd/cosign/cli/sign.go	0.00%	29 Missing ⚠️
cmd/cosign/cli/options/attest.go	0.00%	14 Missing ⚠️
cmd/cosign/cli/options/sign.go	0.00%	11 Missing ⚠️
internal/key/svkeypair.go	81.03%	8 Missing and 3 partials ⚠️
... and 2 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4371      +/-   ##
==========================================
- Coverage   40.10%   33.88%   -6.22%     
==========================================
  Files         155      217      +62     
  Lines       10044    15341    +5297     
==========================================
+ Hits         4028     5199    +1171     
- Misses       5530     9473    +3943     
- Partials      486      669     +183     

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[haydentherapper]

Putting this up for an early review. Only the last commit is new, the first two commits will be merged in other open PRs. I also am currently doing some manual testing.

[haydentherapper]

Testing against staging with a local zot instance:

Sign:

cosign sign --new-bundle-format --use-signing-config --yes localhost:5050/busybox:latest
cosign verify --new-bundle-format --certificate-identity=$email --certificate-oidc-issuer=https://accounts.google.com --use-signed-timestamps localhost:5050/busybox:latest

oras blob fetch --output - localhost:5050/busybox@sha256:2e6e693c1a62b4f9e006eead11076f39b5a7940a71f4c608324568fe12f396fc | jq .

{
  "mediaType": "application/vnd.dev.sigstore.bundle.v0.3+json",
  "verificationMaterial": {
    "certificate": {
      "rawBytes": "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"
    },
    "tlogEntries": [
      {
        "logIndex": "12653",
        "logId": {
          "keyId": "KfSiSX2iRLyhK62SUVL47vVcqqRx/RAewpKJm8IdZTo="
        },
        "kindVersion": {
          "kind": "dsse",
          "version": "0.0.2"
        },
        "inclusionProof": {
          "logIndex": "12653",
          "rootHash": "fYshRW6nXqcskwfN7nsKsSafcKRgg2ecRB2esuCvfsY=",
          "treeSize": "12654",
          "hashes": [
            "MVX3t35pWRVJT8kI8E8VhzXEtaMiBW5X+yTg+c5rRZ8=",
            "xo0nSM6X1VP86U0LV0080T85/1GhoNbKhKWqXs6ittw=",
            "kB/wdWX34RvwCwwrx8hZhzxqDNTmAGNfDsgVOhkWq1I=",
            "vXnnwpJ5OqciN9qMZwmmYK4xEI028u3zHYDuTYmc1co=",
            "OMXJPMCyNGqHkMduha23XycScArnTg26vxwUXJKNVMI=",
            "+frQeMrCfT9QFlGbcibAql8UWJFZmufwvKNxgbpVCA4=",
            "0KNqXR/+75uSLph/Fx2weSQRzJL39gQLZbIvS42Ol+U=",
            "pXaQv2zTqk7DxhnCqnfuzVrpMtX5u3D9hF1QmrEewVY="
          ],
          "checkpoint": {
            "envelope": "log2025-alpha2.rekor.sigstage.dev\n12654\nfYshRW6nXqcskwfN7nsKsSafcKRgg2ecRB2esuCvfsY=\n\n— log2025-alpha2.rekor.sigstage.dev KfSiSWAmlkAgcGnlRA4eqZxfAN9EFtmXTY92ZtSqTTWJtN6Nz+mtWRx0nS38ZZ6k7FC4KgKTbqZ8u3A3NNgSLbqaRAQ=\n"
          }
        },
        "canonicalizedBody": "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"
      }
    ],
    "timestampVerificationData": {
      "rfc3161Timestamps": [
        {
          "signedTimestamp": "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"
        }
      ]
    }
  },
  "dsseEnvelope": {
    "payload": "eyJfdHlwZSI6Imh0dHBzOi8vaW4tdG90by5pby9TdGF0ZW1lbnQvdjEiLCJzdWJqZWN0IjpbeyJkaWdlc3QiOnsic2hhMjU2IjoiYWIzM2VhY2M4MjUxZTM4MDdiODViYjZkYmE1NzBlNDY5OGMzOTk4ZWNhNmYwZmMyY2NiNjA1NzVhNTYzZWE3NCJ9fV0sInByZWRpY2F0ZVR5cGUiOiJodHRwczovL3NpZ3N0b3JlLmRldi9jb3NpZ24vc2lnbi92MSJ9",
    "payloadType": "application/vnd.in-toto+json",
    "signatures": [
      {
        "sig": "MEUCIDxub2b83EhM+W/INJbTNy2qXVercHDScgmazxfIBg5jAiEAy1nC6kILoVlHsIShnCWQhpVc782r8TNeezvkQOsY0Xo="
      }
    ]
  }
}

Attest:

cosign attest --predicate predicate.json --new-bundle-format --use-signing-config --yes localhost:5050/busybox:latest
cosign verify-attestation --new-bundle-format --certificate-identity=$email --certificate-oidc-issuer=https://accounts.google.com --use-signed-timestamps --check-claims localhost:5050/busybox:latest

oras discover localhost:5050/busybox:latest

localhost:5050/busybox@sha256:ab33eacc8251e3807b85bb6dba570e4698c3998eca6f0fc2ccb60575a563ea74
└── application/vnd.dev.sigstore.bundle.v0.3+json
    └── sha256:35e2d0bf2dfcad705b31b1d97f4c54cecbae6ef091b35a42d80e28838f47e3cf

oras blob fetch --output - localhost:5050/busybox@sha256:5a7f96b09c6f4583801e1a79ae39b9d729fac8149f8789cfb2a0cb9066d1e71f | jq .
# A bundle is there!

[haydentherapper]

Note to reviewers: Going to take a pass over trying to reduce duplication.

Edit: Reviewing the code, I'd rather not try to reduce duplication for now between sign and attest. These commands will be nearly identical post-Cosign v3, so I'd rather just remove one later on then try to determine a good API for shared logic between the two right now.