HMAC Verify Data
HMAC Verify Data validates an HMAC signature generated for input data using a shared secret key.
The step recomputes the HMAC (SHA-256) and compares it with the provided signature using the configured comparison mode.
Parameters
TEXT_ENCODING
Encoding used to convert input text into bytes before verification.
Supported values:
- utf8
- unicode
- ascii
- base64
Default: utf8
KEY_ENCODING
Encoding used to convert the secret key into bytes.
Supported values:
- utf8
- base64
- hex
Default: utf8
SIGNATURE_ENCODING
Encoding used to convert the provided signature into bytes (for fixed-time comparison).
Supported values:
- base64 (recommended)
- hex
- utf8
Default: base64
COMPARISON
Specifies how the computed signature should be compared with the provided signature.
Supported values:
- fixedtime (recommended, constant-time comparison)
- ordinal
- ordinalignorecase
Default: fixedtime
TEXT_PARAM
Message parameter name that contains the input text.
Default: TEXT
KEY_PARAM
Parameter name used to resolve the secret key.
The key is resolved in the following order:
- Step Parameters
- Message Parameters
Default: KEY
SIGNATURE_PARAM
Message parameter name containing the signature to verify.
Default: SIGNATURE
RESULT_PARAM
Message parameter name that receives the verification result.
Direction: Out
Default: VALID_SIGNATURE
Execution Context Behavior
- Reads text from TEXT_PARAM.
- Resolves the secret key from KEY_PARAM.
- Reads the provided signature from SIGNATURE_PARAM.
- Converts text and key using their respective encodings.
- Computes HMAC using SHA-256.
- Compares the computed signature with the provided signature using the configured COMPARISON mode:
- fixedtime → constant-time byte comparison
- ordinal → case-sensitive string comparison
- ordinalignorecase → case-insensitive string comparison
- Writes the verification result (
TrueorFalse) to RESULT_PARAM.
Example Configuration
| Parameter | Value |
|---|---|
| TEXT_ENCODING | utf8 |
| KEY_ENCODING | utf8 |
| SIGNATURE_ENCODING | base64 |
| COMPARISON | fixedtime |
| TEXT_PARAM | TEXT |
| KEY_PARAM | KEY |
| SIGNATURE_PARAM | SIGNATURE |
| RESULT_PARAM | VALID_SIGNATURE |
Example Result
VALID_SIGNATURE = True