Module packet 

Packet codec — framing, header, security control block, MAC, trailer.

Spec: §5.9 Tables 1–3, Annex C

Structs

Address

PD bus address.

ControlByte

Decoded control byte.

CtrlFlags

Control byte flags.

PacketBuilderalloc

Builder for a single OSDP packet.

ParsedPacket

View of a parsed OSDP packet, borrowed from the input slice.

Scballoc

Owned Security Control Block.

ScbView

Borrowed view of a parsed Security Control Block.

Sqn

Sequence number (0..=3).

Enums

ScsType

Security block type byte (SEC_BLK_TYPE).

Trailer

Decoded packet trailer.

Constants

HEADER_LEN

Length of the fixed OSDP header (SOM, ADDR, LEN_LSB, LEN_MSB, CTRL).

MAC_LEN

MAC trailer length on the wire (the first 4 bytes of the computed MAC).

Functions

checksum8

Compute the 8-bit OSDP checksum over bytes.

crc16

Compute the CRC-16/KERMIT over bytes.

crc16_le

Compute the CRC-16/KERMIT and return it as little-endian bytes.

Type Aliases

Packetalloc

Re-export of the high-level PacketBuilder under a friendlier name.