Encoding & cryptographyReference

crypt.hmac

Calculate an HMAC-SHA256 authentication code.

Details#

Calculate an HMAC-SHA256 authentication code. Base64-encoded 32-byte HMAC. Unsupported algorithms or provider failure raise errors.

crypt.hmac(key: string, data: string, algorithm: string?): string

Parameter	Type	Description
`key`	`string`	Raw key bytes, not an implicitly decoded Base64 key.
`data`	`string`	Raw message bytes.
`algorithm`optional	`string`	Only sha256 is supported, case-insensitively; default sha256.

Base64-encoded 32-byte HMAC. Unsupported algorithms or provider failure raise errors.

local key = crypt.random(32)
local tag = crypt.hmac(key, "Local message")
print(#crypt.base64decode(tag)) -- 32