Struct Checksum 

pub struct Checksum { /* private fields */ }

Generates a CRC checksum according to the algorithm used in Silkroad Online.

Just like a hash, given the same input (seed & data), it will produce the same output. The seed is expected to be generated randomly and exchanged prior. Then the output can be used to ensure no accidental changes have been made to the data.

let checksum = Checksum::new(random::<u32>());
let crc = checksum.generate_byte(&[0x01, 0x02]);

While the seed is considered a u32, only the lower 8 bits are actually used; any other will be discarded. Technically, it would be more correct for this seed to accept a u8 instead to ensure this on a type level. However, we’re keeping it as a u32 because inside the silkroad packets the seed occupies a u32. We want to keep this in sync. For now, the following is thus correct:

let checksum = Checksum::new(10 + 256);
let checksum2 = Checksum::new(10);
assert_eq!(checksum, checksum2);

Implementations

impl Checksum

pub fn new(seed: u32) -> Self

Creates a new checksum from a given seed.

pub fn generate_byte(&self, buffer: &[u8]) -> u8

Generates the CRC byte for the given buffer.

pub fn builder(&self) -> ChecksumBuilder<'_>

Creates a ChecksumBuilder for a more fluent api.

Trait Implementations

impl Clone for Checksum

fn clone(&self) -> Checksum

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Checksum

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for Checksum

fn eq(&self, other: &Checksum) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for Checksum

impl Eq for Checksum

impl StructuralPartialEq for Checksum