vdods
commented
11 months ago Ok, it looks like the call let json = ssi_json_ld::syntax::to_value_with(copy, Default::default).unwrap(); in Credential::to_dataset_for_signing is where it goes wrong.
Comparison of the json variable when serde_json/arbitrary_precision feature is not enabled and when it is enabled:
When it is not enabled (irrelevant detail truncated):
...
Meta(
"chainId",
Span {
start: 0,
end: 0,
},
): Meta(
Number(
"5",
),
Span {
start: 0,
end: 0,
},
),
...When it is enabled:
...
Meta(
"chainId",
Span {
start: 0,
end: 0,
},
): Meta(
Object(
{
Meta(
"$serde_json::private::Number",
Span {
start: 0,
end: 0,
},
): Meta(
String(
"5",
),
Span {
start: 0,
end: 0,
},
),
},
),
),
...So it looks like because ssi_json_ld::syntax::to_value_with calls serde::Serialize, it's inheriting the problem described here. I'm not very familiar with how serde Serializers are implemented, but perhaps it's possible to somehow specify special behavior for "$serde_json::private::Number".
Unfortunately I'm not able to disable the arbitrary_precision feature, since it's buried my dependency on the ethers-rs crate. But ideally that crate would avoid using the arbitrary_precision flag.
Related:
- https://github.com/serde-rs/json/issues/505
- https://github.com/gakonst/ethers-rs/issues/2206 (including ethers-rs crate was the original cause of this conflict for me)
I'm currently digging into the precise cause, but it seems like the something in Credential/Presentation's impl of
to_dataset_for_signingis not correctly forming the dataset when this arbitrary_precision feature is enabled in the serde_json crate. The arbitrary_precision feature causes numbers to be stored as strings, so perhaps to_dataset_for_signing is incorrectly canonicalizing numbers as strings.The specific error returned by Credential::verify / Presentation::verify is
"Verification equation was not satisfied"if ed25519-dalek is used, and"ring::error::Unspecified"if ring is used.