# verify_signers_with_message · FT4 Rell API · Chromia Docs (concept)

> function verify_ signers_ with_ message(ft_ and_ evm_ signers: list<byte_ array>, message: text, gtx_ transaction: gtx_ transaction) Does what verify_signe

Source: https://docs.chromia.com/pages/ft4-rell/-f-t4-library/lib.ft4.core.auth/verify_signers_with_message/

FUNCTION

# verify\_signers\_with\_message

```signature
function verify_signers_with_message(ft_and_evm_signers: list<byte_array>, message: text, gtx_transaction: gtx_transaction)
```

[Source](https://gitlab.com/chromaway/ft4-lib/-/blob/development/rell/src/lib/ft4/core/auth/authentication.rell#lines-646)

Does what `verify_signers` does, but receives the message as a parameter instead of using
the auth message of the current operation.

Throws `"MISMATCHED SIGNATURES"` if any of the signers and signatures on the `evm_signatures`
operation don't match in the exact order they're found.

Throws `"MISSING SIGNATURE"` if:

* an EVM signer is specified but the signature is not found in the `evm_signatures` operation.
* an FT signer is specified but the signature is not found in the signers of the transaction.

Throws `"UNSUPPORTED SIGNER"` if a signer passed is neither an EVM nor an FT signer,
which means the byte array length is different from `EVM_ADDRESS_SIZE` and `FT_PUBKEY_SIZE`

Throws if the message is empty.

Throws if any signatures in `evm_signatures` is null or missing, or if there's extra
signatures in that operation.

**Parameters**

* **ft\_and\_evm\_signers** — the signers that are expected to be found.
* **message** — the message that was signed.
* **gtx\_transaction** — the transaction that was signed.

**See Also**

* [verify\_signers](https://docs.chromia.com/pages/ft4-rell/-f-t4-library/lib.ft4.core.auth/verify_signers/) — if the message that must be signed is the one defined in the `auth_handler` for the current operation

[View this page on docs.chromia.com](https://docs.chromia.com/pages/ft4-rell/-f-t4%20-library/lib.ft4.core.auth/verify_signers_with_message.html)Generated API reference, mirrored from the live docs