VeriFone MX800 Series - Errors Returned by Write(); Response

IPP MS AND DUKPT COMMUNICATIONS PACKETS
Packet 25: Check the DUKPT Engine
M
X
800 SERIES PROGRAMMERS GUIDE 333
Errors returned by write()
Some packet format errors are caught when the packet is written to the IPP. In this
case, write() returns –1 and errno set. The packet is not ACKed or NAKed, and
no response packet returns.
DUKPT Packet 75:
DUKPT Accept and
Encrypt PIN/Data
Authentication
Response
Response packet to packet DUKPT Z69 Packet: Accept and Encrypt PIN / Data
Authentication Request or Packet 78: DUKPT Accept and Encrypt PIN/Data
Authentication Test Request to the controller with confirmation status.
Authentication code #1 is the MAC on this message. If the request is approved,
the MAC received with the approval response message exactly matches
authentication code #2. If the request is declined, the MAC received with the
decline response message must exactly match authentication code #3.
DUKPT Packet 75
Length:
• MAX: 57 characters
• MIN: 67 characters
Z60 Format Error errno
No <FS> EINVAL
Table 83 DUKPT Packet 75 Format
Data Element Characteristic Comments
<STX> 1H Start of text, value: 02h
Packet Type 2AN Value: 75
[Auth. Code #1] 8H Authentication code #1, message MAC
In ANSI mode, Auth Code is padded with all 0s
(0x30h).
[Auth. Code #2] 8H Authentication code #2, transaction approved
check value
In ANSI mode, Authentication Code #2 is the left
4 bytes of the MAC value.
[Auth. Code #3] 8H Authentication code #3, transaction declined
check value
In ANSI mode, Authentication Code #3 is the
right 4 bytes of the MAC value.
Function Key 1N Value is 0, Function Key Indicator feature not
implemented
Key Serial
Number
10–20H Hexadecimal (leading Fs suppressed.);
Included only if PIN entered; Length is 0 if no PIN
entered
Encrypted PIN
Block
16H The 64 bit encrypted PIN block represented as
16 hexadecimal digits.
Length is 0, if no PIN entered.
<ETX> 1H End of text, value: 03h
{LRC} 1H Error check character