> Aztec.nr API reference, v6.0.0 (mainnet and testnet). Index: https://docs.aztec.network/aztec-nr-api/v6.0.0/llms.txt

# Function verify_signature

Module: `std::ecdsa_secp256k1`

```rust
pub fn verify_signature(
    public_key_x: [u8; 32],
    public_key_y: [u8; 32],
    signature: [u8; 64],
    message_hash: [u8; 32],
) -> bool
```

Verifies a ECDSA signature over the secp256k1 curve.

- inputs:

  - x coordinate of public key as 32 bytes
  - y coordinate of public key as 32 bytes
  - the signature, as a 64 bytes array The signature internally will be represented as `(r, s)`, where `r` and `s` are fixed-sized big endian scalar values. As the `secp256k1` has a 256-bit modulus, we have a 64 byte signature while `r` and `s` will both be 32 bytes. We expect `s` to be normalized. This means given the curve's order, `s` should be less than or equal to `order / 2`. This is done to prevent malleability. For more context regarding malleability you can reference BIP 0062.
  - the hash of the message, as a vector of bytes

- output: false for failure and true for success