AMD Alchemy Au1550 Security Network Processor Data Book
183
Security Engine
30283D
7.3.5
SA Record Format
The security association (SA) record, along with the packet descriptor, provide the packet engine all of the information
needed to process an operation. The SA record contains all of the information which is either static for the lifetime of the
association, or is dynamically updated by the security engine. Any control information which must be modified by the host
for each operation is contained in the descriptor.
For bulk, AES, 3DES, and DES operations, the security engine supports Revision 1 of the SA structure. The security
engine also supports Revision 0 of the SA structure, but SA Rev 1 is recommended for new applications. (The SA Rev 0
format does not support AES operations.) The SA structure revision (Rev 1 or Rev 0) is specified in the SA-revision bit (bit
15) of the Command1 field.
The security engine also supports ARC4 operation. When the ARC4 algorithm is selected (Command0[CA]=0010), the
security engine uses the ARC4 structure for the SA record. The supported SA record structures are shown below.
AES/DES IPsec and Bulk Mode (Rev 1)
Offset
Description
bytes
Word 0
Command0
1-4
Word 1
Command1
5-8
Word 2
Reserved
9-12
Word 3
Reserved
13-16
Word 4
Key1 bytes 3:0
DE
S
3D
ES
AE
S
17-20
Word 5
Key1 bytes 7:4
21-24
Word 6
Key2 bytes 3:0
25-28
Word 7
Key2 bytes 7:4
29-32
Word 8
Key3 bytes 3:0
33-36
Word 9
Key3 bytes 7:4
37-40
Word 10
Key4 bytes 3:0
41-44
Word 11
Key4 bytes 7:4
45-48
Word 12
Inner Digest bytes 3:0
(A)
49-52
Word 13
Inner Digest bytes 7:4
(B)
53-56
Word 14
Inner Digest bytes 11:8
(C)
57-60
Word 15
Inner Digest bytes 15:12
(D)
61-64
Word 16
Inner Digest bytes 19:16
(E)
65-68
Word 17
Outer Digest bytes 3:0
(A)
69-72
Word 18
Outer Digest bytes 7:4
(B)
73-76
Word 19
Outer Digest bytes 11:8
(C)
77-80
Word 20
Outer Digest bytes 15:12
(D)
81-84
Word 21
Outer Digest bytes 19:16
(E)
85-88
Word 22
SPI
89-92
Word 23
Sequence Number
93-96
Word 24
Sequence number mask [31:0]
97-100
Word 25
Sequence number mask [63:32]
101-104
Word 26
Reserved
105-108
Word 27
Pointer to State Record
109-112
Word 28
Reserved
113-116
Word 29
Reserved
117-120
Word 30
SA Management Field 0
121-124
Word 31
SA Management Field 1
125-128
State Record (Rev 1)
Offset
Description
Word 0
Saved IV bytes 3:0
D
ES/
3D
ES
AE
S
Word 1
Saved IV bytes 7:4
Word 2
Saved IV bytes 11:8
Word 3
Saved IV bytes 15:12
Word 4
Saved Hash byte count
Word 5
Saved Inner Digest bytes 3:0
Word 6
Saved Inner Digest bytes 7:4
Word 7
Saved Inner Digest bytes 11:8
Word 8
Saved Inner Digest bytes 15:12
Word 9
Saved Inner Digest bytes 19:16