Improper encoding of JWK for RSA keys (The JWK "n" member contained a leading zero.)

[wellcaffeinated]

Affected version picky 6.3.0

Problem: When attempting to use the JWK that picky created in chrome, i get this error:

DOMException: The JWK "n" member contained a leading zero.

This is related to the following:

• Webcrypto API anvilresearch/connect-js#7
• Leading Zeros OADA/rsa-pem-to-jwk#1
• https://bugs.chromium.org/p/chromium/issues/detail?id=383998

For what it's worth, i was doing this:

let pk = picky::key::PublicKey::from_rsa_der(&der)?;
let mut jwk = picky::jose::jwk::Jwk::from_public_key(&pk)?
jwk.alg = Some(picky::jose::jwk::Jwa::Sig(picky::jose::jws::JwsAlg::RS256));

And it gave me the output:

{
  "alg": "RS256",
  "e": "AQAB",
  "kty": "RSA",
  "n": "ANA4_xFppBBf56Vcbt2CRQTe35qaGzFvo30mIpuwJjAP9H1lhoGwWPAISL9f0unC4zPIZWsOf8xSXGSgjLYJkguPUph17qznKZZ1hH2Wbti-2ES-1M_MJS4x6oC2v-9UmE6xV1mVI6mepBwqrKMY2Fe2HZWS1zk7FKnWmPz_dIbzZyP8ctrbHFyZqgJCJjSLHwO6Lzh0K4cGdMn6WGnzgj6rYj65qDTSvTXoToSxHDUeOYoVn0ERqzm-DinJlXGYyE-Ucqkx7u7nqWSQysE1G8zlUVQ5ilv38FfHf2Gi7rI7k3PxBNWNme95UADzlYQGUtW-YpTkR9Mfsd4-wliA5Yc"
}

Note the leading zero: ANA4_xFpp...

[CBenoit]

Thank you for reporting this!

[CBenoit]

@wellcaffeinated could you confirm the issue is fixed on your side as well when using the patch from #141?
In your Cargo.toml:

picky = { git = "https://github.com/Devolutions/picky-rs", rev = "5f1862f7a8f3f5f21e28a801377b3e926e133f97", … }

Thank you!

[wellcaffeinated]

Hmm.... I'm having some trouble with conflicting versions now

error: failed to select a version for `zeroize`.
    ... required by package `num-bigint-dig v0.8.1`
    ... which satisfies dependency `num-bigint-dig = "^0.8.1"` of package `picky v7.0.0-rc.2 (https://github.com/Devolutions/picky-rs?rev=5f1862f7a8f3f5f21e28a801377b3e926e133f97#5f1862f7)`
    ... which satisfies git dependency `picky` of package `hsm-bridge v0.1.0 (/Users/wellcaffeinated/Documents/github/buffbeacon/twine-ipfs/beacon/hsm-bridge)`
versions that meet the requirements `^1.5` are: 1.5.4, 1.5.3

all possible versions conflict with previously selected packages.

  previously selected package `zeroize v1.3.0`
    ... which satisfies dependency `zeroize = "^1"` (locked to 1.3.0) of package `crypto-bigint v0.3.2`
    ... which satisfies dependency `crypto-bigint = "^0.3"` (locked to 0.3.2) of package `der v0.5.1`
    ... which satisfies dependency `der = "^0.5"` (locked to 0.5.1) of package `ecdsa v0.13.4`
    ... which satisfies dependency `ecdsa-core = "^0.13"` (locked to 0.13.4) of package `p256 v0.10.1`
    ... which satisfies dependency `p256 = "^0.10"` (locked to 0.10.1) of package `yubihsm v0.40.0`
    ... which satisfies dependency `yubihsm = "^0.40"` (locked to 0.40.0) of package `hsm-bridge v0.1.0 (/Users/wellcaffeinated/Documents/github/buffbeacon/twine-ipfs/beacon/hsm-bridge)`

failed to select a version for `zeroize` which could resolve this conflict

[CBenoit]

Maybe you could try update your Cargo.lock with

$ cargo update -p zeroize

[wellcaffeinated]

no dice :(

error: failed to select a version for `zeroize`.
    ... required by package `curve25519-dalek v3.2.1`
    ... which satisfies dependency `curve25519-dalek = "^3"` (locked to 3.2.1) of package `ed25519-dalek v1.0.1`
    ... which satisfies dependency `ed25519-dalek = "^1"` (locked to 1.0.1) of package `yubihsm v0.40.0`
    ... which satisfies dependency `yubihsm = "^0.40"` (locked to 0.40.0) of package `hsm-bridge v0.1.0 (/Users/wellcaffeinated/Documents/github/buffbeacon/twine-ipfs/beacon/hsm-bridge)`
versions that meet the requirements `>=1, <1.4` are: 1.3.0, 1.2.0, 1.1.1, 1.1.0, 1.0.0

all possible versions conflict with previously selected packages.

  previously selected package `zeroize v1.5.3`
    ... which satisfies dependency `zeroize = "^1.5"` of package `num-bigint-dig v0.8.1`
    ... which satisfies dependency `num-bigint-dig = "^0.8.1"` of package `picky v7.0.0-rc.2 (https://github.com/Devolutions/picky-rs?rev=5f1862f7a8f3f5f21e28a801377b3e926e133f97#5f1862f7)`
    ... which satisfies git dependency `picky` of package `hsm-bridge v0.1.0 (/Users/wellcaffeinated/Documents/github/buffbeacon/twine-ipfs/beacon/hsm-bridge)`

failed to select a version for `zeroize` which could resolve this conflict

[CBenoit]

Oh, the error changed and is actually showing something useful!
Looks like curve25519-dalek is depending on zeroize >= 1, <1.4, but since num-bigint-dig is depending on zeroize ^1.5, there is no version that can be used by both :/

Here are some relevant links:

• Consider pinning minor version of 'zeroize' dependency dalek-cryptography/curve25519-dalek#362
• dalek-cryptography/curve25519-dalek@b6a7406#r65843797

I understand curve25519-dalek did that because they have a different policy about MSRV.

Now, there is no good solution in such case, ideally curve25519-dalek could bump their MSRV. There is a patch for just that you could use: dalek-cryptography/curve25519-dalek#386 (make sure to pin a specific commit using rev so you don’t pull arbitrary new commits implicitly)