Signatures ​

The type of signatures in SmartPy is sp.TSignature.
The corresponding type in Michelson is

Michelson signature

See reference Signatures and State Channels.

Operations ​

Check signature ​

sp.check_signature(<public_key>, <signature>, <original_content_bytes>)
Determine whether the signature s (a sp.TSignature value) has been produced by signing b (a sp.TBytes value) with the private key corresponding to k (a sp.TKey public key value).

Example ​

k = sp.key("edpkuBknW28nW72KG6RoHtYW7p12T6GKc7nAbwYX5m8Wd9sDVC9yav")
s = sp.signature("edsigu3QszDjUpeqYqbvhyRxMpVFamEnvm9FYnt7YiiNt9nmjYfh8ZTbsybZ5WnBkhA7zfHsRVyuTnRsGLR6fNHt1Up1FxgyRtF")
b = sp.bytes("0x00aabb")

sp.check_signature(k, s, b)

Michelson CHECK_SIGNATURE

Make signature ​

sp.make_signature(secret_key, message, message_format = 'Raw')
Forge a signature compatible with sp.check_signature(...); the message is a sp.TBytes value (usually the result of an sp.pack call), the message_format can also be "Hex" in which case the message will be interpreted as an hexadecimal string.

Example ​

sp.make_signature(
    "edskRq1xuW7TCYzdFm1JQLi1Hz4MNDVP6ukQHVEEh3bVqyuzv7pXXjaGsXZuMbwtd3kQFp3LQ7GQzkLeprNEijKhQKzsxrYrUz",
    sp.bytes("0x00aabb"),
    message_format = 'Raw'
)

sp.make_signature is not available for compilation to Michelson as a smart contract cannot manipulate secret keys.
It can only be used in Tests and Scenarios.