Struct openssl::hash::Hasher

pub struct Hasher { /* fields omitted */ }

Provides message digest (hash) computation.

Examples

Calculate a hash in one go:

use openssl::hash::{hash, MessageDigest};

let data = b"\x42\xF4\x97\xE0";
let spec = b"\x7c\x43\x0f\x17\x8a\xef\xdf\x14\x87\xfe\xe7\x14\x4e\x96\x41\xe2";
let res = hash(MessageDigest::md5(), data).unwrap();
assert_eq!(&*res, spec);

Supply the input in chunks:

use openssl::hash::{Hasher, MessageDigest};

let data = [b"\x42\xF4", b"\x97\xE0"];
let spec = b"\x7c\x43\x0f\x17\x8a\xef\xdf\x14\x87\xfe\xe7\x14\x4e\x96\x41\xe2";
let mut h = Hasher::new(MessageDigest::md5()).unwrap();
h.update(data[0]).unwrap();
h.update(data[1]).unwrap();
let res = h.finish().unwrap();
assert_eq!(&*res, spec);

Use an XOF hasher (OpenSSL 1.1.1+):

#[cfg(ossl111)]
{
    use openssl::hash::{hash_xof, MessageDigest};

    let data = b"\x41\x6c\x6c\x20\x79\x6f\x75\x72\x20\x62\x61\x73\x65\x20\x61\x72\x65\x20\x62\x65\x6c\x6f\x6e\x67\x20\x74\x6f\x20\x75\x73";
    let spec = b"\x49\xd0\x69\x7f\xf5\x08\x11\x1d\x8b\x84\xf1\x5e\x46\xda\xf1\x35";
    let mut buf = vec![0; 16];
    hash_xof(MessageDigest::shake_128(), data, buf.as_mut_slice()).unwrap();
    assert_eq!(buf, spec);
}

Warning

Don't actually use MD5 and SHA-1 hashes, they're not secure anymore.

Don't ever hash passwords, use the functions in the pkcs5 module or bcrypt/scrypt instead.

For extendable output functions (XOFs, i.e. SHAKE128/SHAKE256), you must use finish_xof instead of finish and provide a buf to store the hash. The hash will be as long as the buf.

Methods

impl Hasher

pub fn new(ty: MessageDigest) -> Result<Hasher, ErrorStack>

Creates a new Hasher with the specified hash type.

pub fn update(&mut self, data: &[u8]) -> Result<(), ErrorStack>

Feeds data into the hasher.

pub fn finish(&mut self) -> Result<DigestBytes, ErrorStack>

Returns the hash of the data written and resets the non-XOF hasher.

Trait Implementations

impl Send for Hasher

impl Drop for Hasher

fn drop(&mut self)

Executes the destructor for this type.

impl Sync for Hasher

impl Clone for Hasher

Important traits for Hasher

impl Write for Hasher

fn clone(&self) -> Hasher

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Write for Hasher

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_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.