Struct blake::Blake

pub struct Blake { /* fields omitted */ }

Hashing state for multiple data sets.

Example

Hashing a string split into multiple chunks.

let mut state = Blake::new(256).unwrap();

state.update(b"Abolish ");
state.update(b"the ");
state.update(b"bourgeoisie");
state.update(b"!");

let mut result = [0; 32];
state.finalise(&mut result);
assert_eq!(Vec::from_iter(result.iter().map(|&i| i)),
           vec![0x35, 0xBF, 0x9C, 0x70, 0xFF, 0x63, 0xF1, 0x26,
                0x6A, 0xE7, 0x2C, 0xC9, 0x94, 0x6F, 0x59, 0xBB,
                0x0B, 0x21, 0xD8, 0xCC, 0x8E, 0x4D, 0xBB, 0x53,
                0x24, 0xDF, 0x10, 0xB7, 0x11, 0xF9, 0x82, 0x1C]);

A Write implementation is also provided:

let mut state = Blake::new(256).unwrap();
io::copy(&mut &b"The lazy fox jumps over the lazy dog."[..], &mut state).unwrap();

let mut result = [0; 32];
state.finalise(&mut result);
assert_eq!(Vec::from_iter(result.iter().map(|&i| i)),
           vec![0xF2, 0xE5, 0xA9, 0xD0, 0x93, 0xD8, 0xAA, 0x23,
                0x4E, 0x6C, 0x54, 0x50, 0x61, 0xE8, 0x17, 0xBE,
                0x83, 0x8B, 0x57, 0xD8, 0x99, 0x8F, 0x15, 0xDF,
                0x72, 0xE1, 0x03, 0x7F, 0xBF, 0xEB, 0x4F, 0xC7]);

Methods

impl Blake

pub fn new(hashbitlen: i32) -> Result<Blake>

Create a new hash state and initialise it with the given bit length.

hashbitlen is the hash output length.
Valid values:

• 224,
• 256,
• 384,
• 512.

Returns:

• Err(BlakeError::BadHashbitlen) if hashbitlen is not any of the mentioned above, or
• Ok(Blake) if initialisation succeeds.

Examples

Incorrect hashbitlen

assert_eq!(Blake::new(0).map(|_| ()), Err(blake::BlakeError::BadHashbitlen));

Creating a 512-long state

Blake::new(512).unwrap();

pub fn add_salt(&mut self, salt: &[u8]) -> Result<()>

Add a salt to the hash function.

Returns:

• Err(BlakeError::Fail) if called after Blake::update(), or
• Ok(()), if called before Blake::update().

The salt's length depends on the hash function's length.

hash function length	salt length
224 bits	128 bits
256 bits	128 bits
384 bits	256 bits
512 bits	256 bits

Examples

let mut result_unsalted = [0; 64];
let mut result_salted   = [0; 64];

let mut state_unsalted = Blake::new(512).unwrap();
let mut state_salted   = Blake::new(512).unwrap();

state_salted.add_salt(b"Violent  murder  of  the  proles").unwrap();

state_unsalted.update(&[]);
state_salted  .update(&[]);

state_unsalted.finalise(&mut result_unsalted);
state_salted  .finalise(&mut result_salted);

assert!(Vec::from_iter(result_unsalted.iter().map(|&i| i)) !=
        Vec::from_iter(result_salted  .iter().map(|&i| i)))

pub fn update(&mut self, data: &[u8])

Append the provided data to the hash function.

Examples

Hashing a part of a short story

let mut result = [0; 64];

let mut state = Blake::new(512).unwrap();
state.update("    Serbiańcy znowu się pochlali, ale w sumie".as_bytes());
state.update("czegoż się po wschodnich słowianach spodziewać, swoją".as_bytes());
state.update("drogą. I, jak to wszystkim homo sapiensom się dzieje".as_bytes());
state.update("filozofować poczęli.".as_bytes());
state.finalise(&mut result);

assert_eq!(Vec::from_iter(result.iter().map(|&i| i)),
           vec![0xA2, 0x30, 0x50, 0x18, 0x10, 0x0D, 0x53, 0x61,
                0xC2, 0x2D, 0x61, 0x0A, 0x23, 0x4E, 0xA5, 0x28,
                0x18, 0x89, 0xA6, 0x44, 0x6E, 0xE1, 0xC4, 0x8A,
                0xDF, 0xD0, 0x6A, 0xDB, 0x1C, 0x00, 0x06, 0xA9,
                0x05, 0x0A, 0xCE, 0xB3, 0x43, 0x14, 0xB8, 0xB0,
                0x3F, 0xA3, 0xB7, 0x70, 0x5D, 0xFC, 0x14, 0xB9,
                0xAA, 0xCA, 0xDC, 0x5B, 0x34, 0x96, 0x0B, 0x3C,
                0x87, 0x1F, 0x69, 0x46, 0xCD, 0xC2, 0xB2, 0x14]);

pub fn finalise(&mut self, hashval: &mut [u8])

Finish hashing and store the output result in the provided space.

The provided space must not be smaller than the hash function's size, if the provided space is smaller than the hash function's size, the behaviour is undefined.

Examples

Storing and verifying results of all possible sizes.

let mut result_224 = [0; 28];
let mut result_256 = [0; 32];
let mut result_384 = [0; 48];
let mut result_512 = [0; 64];

let mut state_224 = Blake::new(224).unwrap();
let mut state_256 = Blake::new(256).unwrap();
let mut state_384 = Blake::new(384).unwrap();
let mut state_512 = Blake::new(512).unwrap();

state_224.update(b"The lazy fox jumps over the lazy dog.");
state_256.update(b"The lazy fox jumps over the lazy dog.");
state_384.update(b"The lazy fox jumps over the lazy dog.");
state_512.update(b"The lazy fox jumps over the lazy dog.");

state_224.finalise(&mut result_224);
state_256.finalise(&mut result_256);
state_384.finalise(&mut result_384);
state_512.finalise(&mut result_512);

assert_eq!(Vec::from_iter(result_224.iter().map(|&i| i)),
           vec![0x34, 0x97, 0x89, 0x0F, 0xBC, 0x6A, 0x98, 0x1C,
                0xD2, 0x21, 0x34, 0x97, 0xE4, 0xA8, 0x0A, 0x66,
                0xD6, 0x5F, 0x4C, 0x05, 0x3D, 0x71, 0x0F, 0x7E,
                0xAB, 0x81, 0xA4, 0x2F]);
assert_eq!(Vec::from_iter(result_256.iter().map(|&i| i)),
           vec![0xF2, 0xE5, 0xA9, 0xD0, 0x93, 0xD8, 0xAA, 0x23,
                0x4E, 0x6C, 0x54, 0x50, 0x61, 0xE8, 0x17, 0xBE,
                0x83, 0x8B, 0x57, 0xD8, 0x99, 0x8F, 0x15, 0xDF,
                0x72, 0xE1, 0x03, 0x7F, 0xBF, 0xEB, 0x4F, 0xC7]);
assert_eq!(Vec::from_iter(result_384.iter().map(|&i| i)),
           vec![0xDD, 0x68, 0x1E, 0x3B, 0x56, 0xE4, 0x80, 0x01,
                0x39, 0x5A, 0xF7, 0xB7, 0x36, 0x7E, 0x50, 0xD2,
                0x74, 0x61, 0x2B, 0xC8, 0xCB, 0xFB, 0x42, 0xEE,
                0x0C, 0xEC, 0x30, 0x45, 0x9C, 0x8D, 0x01, 0x66,
                0xFC, 0xB5, 0x42, 0xE2, 0x8C, 0xB0, 0x59, 0x72,
                0x8D, 0x7B, 0x0A, 0x16, 0x05, 0x4E, 0xB2, 0xEB]);
assert_eq!(Vec::from_iter(result_512.iter().map(|&i| i)),
           vec![0x9A, 0xD4, 0x66, 0xCF, 0x81, 0x8B, 0x46, 0x9D,
                0x29, 0x8C, 0x62, 0x00, 0xAC, 0xD3, 0x06, 0xF9,
                0xA2, 0xF4, 0xA4, 0x9E, 0x26, 0x8C, 0xA1, 0x17,
                0xB5, 0x8F, 0x37, 0x84, 0x86, 0x35, 0x1B, 0x0A,
                0x71, 0x1B, 0x60, 0xD4, 0x1B, 0x68, 0x7F, 0xD3,
                0x5F, 0x30, 0xBE, 0x2E, 0x00, 0xA8, 0x25, 0xD6,
                0x66, 0x6D, 0x9C, 0x4C, 0x23, 0xA5, 0x23, 0xD3,
                0x10, 0xA0, 0x58, 0x3F, 0x1E, 0x7C, 0xCC, 0xFE]);

Trait Implementations

impl Drop for Blake

fn drop(&mut self)

Executes the destructor for this type.

impl Write for Blake

The Write implementation updates the state with the provided data.

For example, to hash a file:

let mut state = Blake::new(256).unwrap();
io::copy(&mut File::open("LICENSE").unwrap(), &mut state).unwrap();

let mut result = [0; 32];
state.finalise(&mut result);
assert_eq!(Vec::from_iter(result.iter().map(|&i| i)),
           vec![0xED, 0xE4, 0xD8, 0xF8, 0x49, 0x25, 0xD0, 0xBD,
                0x06, 0xA4, 0xDC, 0x1C, 0xFD, 0x1B, 0x45, 0x62,
                0xA4, 0xBD, 0x35, 0x25, 0x76, 0x9B, 0x97, 0xF1,
                0x9B, 0x21, 0xC8, 0xDF, 0xDC, 0x4A, 0x80, 0xB1]);

fn write(&mut self, buf: &[u8]) -> Result<usize>

Write a buffer into this writer, returning how many bytes were written.

fn flush(&mut self) -> Result<()>

Flush this output stream, ensuring that all intermediately buffered contents reach their destination.

fn write_vectored(&mut self, bufs: &[IoSlice]) -> Result<usize, Error>

Like write, except that it writes from a slice of buffers.

fn write_all(&mut self, buf: &[u8]) -> Result<(), Error>

Attempts to write an entire buffer into this writer.

fn write_all_vectored(&mut self, bufs: &mut [IoSlice]) -> Result<(), Error>

🔬 This is a nightly-only experimental API. (write_all_vectored)

Attempts to write multiple buffers into this writer.

fn write_fmt(&mut self, fmt: Arguments) -> Result<(), Error>

Writes a formatted string into this writer, returning any error encountered.

fn by_ref(&mut self) -> &mut Self

Creates a "by reference" adaptor for this instance of Write.