apollo_propeller: add signature verification module

[sirandreww-starkware]

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[reviewable-StarkWare]

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[sirandreww-starkware]

• apollo_propeller: add minimal config #11196 : 2 dependent PRs (#11197 , #11942 )
• apollo_propeller: add behaviour skeleton #11195
• apollo_propeller: add Event enum to types #11194
• apollo_propeller: add dial upgrade error handling to handler #11074
• apollo_propeller: add rate-limited queue length warnings #11073
• apollo_propeller: add concurrent streams support to handler #11072
• apollo_propeller: implement outbound substream with message batching #11071
• apollo_propeller: add handler helper methods #11070
• apollo_propeller: use protobuf type in handler send queue #11069
• apollo_propeller: reorder handler structs #11068
• apollo_propeller: add inbound substream handling to receive units #11067
• apollo_propeller: add receive queue and emit logic to handler #11066
• apollo_propeller: add handler skeleton with TODOs #11065
• apollo_propeller: add protocol upgrade for libp2p streams #11064
• apollo_protobuf: add prost codec for length-delimited messages #11063
• apollo_propeller: add protobuf conversions for PropellerUnit #11062
• apollo_propeller: add merkle proof verification to validator #11061
• apollo_propeller: integrate tree origin verification in validator #11060
• apollo_propeller: add tree origin verification methods #11059
• apollo_propeller: add unit validator with signature caching #11058
• apollo_propeller: add tree topology core logic #11057
• apollo_propeller: add shard validation error type #11056
• apollo_propeller: add peer set error type #11055
• apollo_propeller: add core unit struct with accessors #11054
• apollo_propeller: add signature verification module #11053 👈 (View in Graphite)
• apollo_propeller: add reconstruction error type #11052
• apollo_propeller: add shard publish error type #11051
• apollo_propeller: add tree generation error type #11050
• apollo_propeller: add ShardSignatureVerificationError #11049
• apollo_propeller: add base types (Channel, ShardIndex, MessageRoot) #11048
• apollo_propeller: add reed-solomon erasure coding #11047
• apollo_propeller: added merkle implementation tests #11206 : 1 other dependent PR (#11572 )
• apollo_propeller: added merkle tree builder #11205
• apollo_propeller: added model merkle implementation #10985
• apollo_propeller: added model merkle proof implementation #11204
• apollo_protobuf: added propeller proto file #10654
• apollo_propeller: new crate for the propeller p2p protocol #11192
• main-v0.14.1-committer

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[guy-starkware]

@guy-starkware reviewed 2 files and all commit messages, and made 2 comments.
Reviewable status: 2 of 3 files reviewed, 2 unresolved discussions (waiting on @noamsp-starkware, @ShahakShama, and @sirandreww-starkware).

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crates/apollo_propeller/src/signature.rs line 21 at r1 (raw file):

        Ok(signature) => Ok(signature),
        Err(e) => Err(ShardPublishError::SigningFailed(e.to_string())),
    }

Maybe map_err with ? at the end is more concise?
Also, I think Shahak mentioned something about transparent errors, may make it possible to just use ?

Code quote:

    match keypair.sign(&msg) {
        Ok(signature) => Ok(signature),
        Err(e) => Err(ShardPublishError::SigningFailed(e.to_string())),
    }

---

crates/apollo_propeller/src/signature.rs line 82 at r1 (raw file):

#[cfg(test)]
mod tests {

Move tests to different file.

[ShahakShama]

@ShahakShama reviewed 1 file and all commit messages, and made 7 comments.
Reviewable status: all files reviewed, 7 unresolved discussions (waiting on @guy-starkware, @noamsp-starkware, and @sirandreww-starkware).

---

crates/apollo_propeller/src/signature.rs line 21 at r1 (raw file):

Previously, guy-starkware wrote…

Maybe map_err with ? at the end is more concise?
Also, I think Shahak mentioned something about transparent errors, may make it possible to just use ?

+1

---

crates/apollo_propeller/src/signature.rs line 82 at r1 (raw file):

Previously, guy-starkware wrote…

Move tests to different file.

+1

---

crates/apollo_propeller/src/signature.rs line 11 at r1 (raw file):

pub const SIGNING_PREFIX: &[u8] = b"<apollo-propeller>";
pub const SIGNING_POSTFIX: &[u8] = b"</apollo-propeller>";

Why do you need a postfix? Also, try to make this shorter
Also, these shouldn't hold apollo because other implementations are going to use the same string. If you really want you can write starknet instead of apollo

---

crates/apollo_propeller/src/signature.rs line 37 at r1 (raw file):

}

pub fn try_extract_public_key_from_peer_id(peer_id: &PeerId) -> Option<PublicKey> {

Are you sure this functionality doesn't exist in libp2p

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crates/apollo_propeller/src/signature.rs line 42 at r1 (raw file):

    // Check if this is an identity multihash (code 0x00)
    if multihash.code() == 0x00 {

Try to find a constant for 0x00 in libp2p. If it doesn't exist, define your own

---

crates/apollo_propeller/src/signature.rs line 71 at r1 (raw file):

    } else {
        // This is a hashed PeerId (SHA-256), cannot extract the original key
        tracing::trace!(peer=%peer_id, multihash_code=%multihash.code(), "PeerId uses hashed multihash, cannot extract public key");

So what is the plan? Ensure all our peer id schemes uses identity?
If that's the case, return error instead of none

---

crates/apollo_propeller/src/signature.rs line 92 at r1 (raw file):

        let merkle_root = MessageRoot([
            1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24,

Define this as [1; 32] to reduce space. I guess the value doesn't matter

[sirandreww-starkware]

@sirandreww-starkware made 7 comments.
Reviewable status: all files reviewed, 7 unresolved discussions (waiting on @guy-starkware, @noamsp-starkware, and @ShahakShama).

---

crates/apollo_propeller/src/signature.rs line 11 at r1 (raw file):

Previously, ShahakShama wrote…

Why do you need a postfix? Also, try to make this shorter
Also, these shouldn't hold apollo because other implementations are going to use the same string. If you really want you can write starknet instead of apollo

I added both just to be safe (same logic that I used for merkle tree hash calculation).
I see your point on apollo an will make this shorter by removing it

---

crates/apollo_propeller/src/signature.rs line 21 at r1 (raw file):

Previously, ShahakShama wrote…

+1

I did your first suggestion and added a todo to do the second...

---

crates/apollo_propeller/src/signature.rs line 37 at r1 (raw file):

Previously, ShahakShama wrote…

Are you sure this functionality doesn't exist in libp2p

You are more than right to question this. From my research I did not find a function that does this, and the gossipsub implementation has a very similar function to this one https://github.com/libp2p/rust-libp2p/blob/e10ce4c1704a529161f62e8538e55a106e4ec2d6/protocols/gossipsub/src/protocol.rs#L227C1-L227C27

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crates/apollo_propeller/src/signature.rs line 42 at r1 (raw file):

Previously, ShahakShama wrote…

Try to find a constant for 0x00 in libp2p. If it doesn't exist, define your own

I could not find this constant anywhere

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crates/apollo_propeller/src/signature.rs line 71 at r1 (raw file):

Previously, ShahakShama wrote…

So what is the plan? Ensure all our peer id schemes uses identity?
If that's the case, return error instead of none

I'm not sure... eliptic curve public keys are short enough so they are put in PeerIDs, so for now all our peer IDs use code 0 because the public key is in the peer id. I also added a function to add a peer with an explicit public key to get around this in the general case (in that case this function will not be called).

I have a feeling that we shouldn't dwell on this for too long because we might need to change the functionality to use starkIDs in the future (to ensure all nodes agree on routing with no possible attacks)

That's the plan for now...

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crates/apollo_propeller/src/signature.rs line 82 at r1 (raw file):

Previously, ShahakShama wrote…

+1

Done

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crates/apollo_propeller/src/signature.rs line 92 at r1 (raw file):

Previously, ShahakShama wrote…

Define this as [1; 32] to reduce space. I guess the value doesn't matter

Done

[guy-starkware]

@guy-starkware reviewed 5 files and all commit messages, and resolved 1 discussion.
Reviewable status: all files reviewed, 6 unresolved discussions (waiting on @noamsp-starkware and @ShahakShama).

[ShahakShama]

@ShahakShama reviewed all commit messages, made 1 comment, and resolved 5 discussions.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @noamsp-starkware and @sirandreww-starkware).

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crates/apollo_propeller/src/signature.rs line 11 at r1 (raw file):

Previously, sirandreww-starkware (Andrew Luka) wrote…

I added both just to be safe (same logic that I used for merkle tree hash calculation).
I see your point on apollo an will make this shorter by removing it

Add a TODO to consider removing these as before

[sirandreww-starkware]

@sirandreww-starkware made 1 comment.
Reviewable status: 1 of 5 files reviewed, 1 unresolved discussion (waiting on @guy-starkware, @noamsp-starkware, and @ShahakShama).

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crates/apollo_propeller/src/signature.rs line 11 at r1 (raw file):

Previously, ShahakShama wrote…

Add a TODO to consider removing these as before

Sure, just stating that the prefix is in gossipsub too...

[ShahakShama]

@ShahakShama reviewed 4 files and all commit messages, made 1 comment, and resolved 1 discussion.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @noamsp-starkware).

[sirandreww-starkware]

@sirandreww-starkware reviewed 5 files and all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @noamsp-starkware).