Validate a Signature

Command:

Validate a signature on a message using a public key.

Notes:

This command requires the optional RSA licence, error code 67 will be returned if the command is not licenced.

See: Using the RSA cryptosystem for details of where valid values of the common parameters can be found.

Field

Length & Type

Details

COMMAND MESSAGE

Message header

m A

(Subsequently returned to the Host unchanged).

Command code

2 A

Value EY.

Hash identifier

2 N

Identifier of the hash algorithm used to hash the message.

Signature Identifier

2 N

Identifier of the signature algorithm used to sign the message.

Pad mode identifier

2 N

Identifier of the pad mode used in signature generation.

01 = PKCS#1 v1.5 method
02 = OAEP

Mask Generation Function

2N

01 = MGF1 as defined in PKCS#1 v2.0 (see Reference 3)

Optional, only present if PAD Mode Identifier is 02 (OAEP)

MGF Hash Function

2N

01 = SHA-1
This field defines the hash function to be used in the MGF. Optional, only present if Pad Mode Identifier is 02 (OAEP)

OAEP Encoding Parameters Length

2N

Optional, only present if Pad Mode Identifier is 02 (OAEP).

OAEP Encoding Parameters

nB

Optional, only present if Pad Mode Identifier is 02 (OAEP)

If present, this field should be encoded according to Reference 3 section 11.2.1. The HSM does not interpret or validate the contents of this field. If OAEP padding is used, but no Encoding Parameters are provided, then OAEP Parameters Length should be “00”, and this field will be empty.

OAEP Encoding Parameters Delimiter

1A

Value “;”.

Optional, only present if Pad Mode Identifier is 02 (OAEP)

Signature length

4 N

Signature length (in bytes).

Signature

n B

Signature to be verified.

Delimiter

1 A

Delimiter, indicates the end of the signature field. Value “;”.

Data length

4 N

Length (in bytes) of the message data to be validated.

Message data

n B

Data to be validated.

Delimiter

1 A

Delimiter, indicates the end of the message data field.  Value  “;”.

MAC

4 B

MAC on the public key and authentication data, calculated using LMK pair 36-37.

Public key

n B

Public key, DER encoded in ASN.1 format (sequence of modulus, exponent).

Authentication data

n B

Optional. Additional data to be included in the MAC calculation (must not include “;”).

End message delimiter

1 C

Optional.  Must be present if a message trailer is present. Value X’19.

Message trailer

n A

Optional.  Maximum length 32 characters.

Field

Length & Type

Details

RESPONSE MESSAGE

Message header

m A

Returned to the Host unchanged.

Response code

2 A

Value EZ.

Error code

2 N

00 : No error

01 : MAC verification failure

02 : Signature verification failure

04 : Public key does not conform to encoding rules

05 : Invalid hash identifier

06 : Invalid signature identifier

07 : Invalid pad mode identifier

13 : LMK error; report to supervisor

15 : Error in input data

47 : DSP error; report to supervisor

74 : Invalid digest info syntax (no-hash mode only)

76 : Public key length error

77 : Clear data block error

79 : Hash algorithm object identifier error

80 : Message length error

81 : Signature length error

85 : Invalid OAEP Mask Generation Function

86 : Invalid OAEP MGF Hash Function

87 : OAEP Parameter Error

88 : OAEP Error

End message delimiter

1 C

Present only if present in the command message. Value X’19.