GP Session Key Calculator (SCP02 / SCP03)

GlobalPlatform secure channel protocol Session Key derivation tool. Supports SCP02 (3DES-CBC key derivation + MAC calculation) and SCP03 (AES-CMAC KDF key derivation). Enter static keys and derivation data to obtain S-ENC, S-MAC, S-DEK, S-RMAC session keys. Essential for smart card security domain development and APDU secure messaging.

SCP02 Session Key Derivation

Derive session keys from static keys using 3DES-CBC.

Static ENC Key (16 bytes Hex):

Static MAC Key (16 bytes Hex):

Static DEK Key (16 bytes Hex, optional):

Derivation Constant (8 bytes Hex):Default: 0182 (SCP02 standard constant)

Sequence Counter / Derivation Data (optional, for C-MAC calculation):

SCP03 Session Key Derivation (AES-CMAC KDF)

Derive session keys from static keys using AES-128-CMAC KDF (NIST SP 800-108).

Static ENC Key (16 bytes Hex, AES-128):

Static MAC Key (16 bytes Hex, AES-128):

Static RMAC Key (16 bytes Hex, optional):

Context / Derivation Context (16 bytes Hex):Typically Host Challenge (8B) + Card Challenge (8B)

Secure Messaging MAC Calculator

Calculate APDU secure messaging MAC values. Supports SCP02 Retail-MAC and SCP03 AES-CMAC.

Session MAC Key (Hex):

MAC Algorithm:

MAC Input Data (Hex, including APDU header + data + padding):

Initial Chaining Vector / ICV (Hex, 8 bytes, SCP02 only, optional):

SCP02 vs SCP03

SCP02: Uses 3DES keys (16 bytes / 128-bit double-length), CBC mode session key derivation. Key types: S-ENC (encryption), S-MAC (message authentication), S-DEK (data encryption key). Derivation constant: 0182.

SCP03: Uses AES-128 keys (16 bytes), CMAC-based KDF session key derivation. Key types: S-ENC, S-MAC, S-RMAC (response MAC). KDF Label = "SCP03" (ASCII).

Security Notice

All computation is performed locally in your browser. Key data is never uploaded to any server. Always use in an isolated environment and clear inputs after use. Never enter production keys in a public network environment.