User's Manual

PIN Pad 791 Programmer’s Manual (PCI POS-A) UDN PM0103-U Rev. 06

Section 6 – Contact EMV Level 2 transaction messages 2015-04-20

Page73

Uniform Industrial Corp. Proprietary and Confidential Total 342 pages

Message T03 Certification Authority Public Key Setup

Format: <STX>T03[Op code][RID][PKI][Hash Algo][Hash][PK Algo][PK Leng]

[PK Exponent]<ETX>[LRC]

<STX>T03[Op code][PK Modulus]<ETX>

Message length: Variable.

Usage: Host can use this command to send the Certification Authority Public key data to

PIN pad, each command can only setup one key but this command can be sent many

times. PIN pad will save those key data inside and use those data when do the

transaction. PIN pad will send the message T04 (Certification Authority Public Key

Setup Response) to host. The data installed into PIN pad via this message, PIN pad

will save it in internal storage structure with a name same as concatenation of value in

[RID] and [PKI] fields. Ex. value in [RID] field is “A000000003”, value in [PKI] filed is

“90”, PIN pad will save these data and give an ID as “A00000000390”.

Message element:

Packet (Load RSA public key):

Field Length

Value and description

T03 3 Message ID

Op code 1 1: Load first part of RSA public key

RID 10

Hexadecimal string, the left 5 bytes of Registered

Application Provider ID

PKI 2 Public Key Index, hexadecimal string. (Refer to

EMV 4.3, tag ‘9F22’)

Hash

Algorithm

2 Hash Algorithm Index, hexadecimal string

‘01’: SHA-1. Now, PIN pad accepts only ‘01’.

Hash 40 Hash checksum, hexadecimal

Sha1(PKModules)

Sha1(RID+PKI+PKModules+PKExp)

Algorithm

2 Public Key Algorithm, hexadecimal string

‘01’: RSA digital signature. Now, PIN pad accepts

only ‘01’.

PK Leng 2 Public Key size, hexadecimalstring, for example:

‘80’ = 128 bytes = 1024 bits

Exponent

1 Public Key Exponent’s size, hexadecimal

‘1’: 3

‘2’: 2