src/lib/hash-method.c

	hash-method.c revision ba706bd508fdbe3e6c971769d0c913b32bf458eb
/* Copyright (c) 2010-2017 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "md4.h"
#include "md5.h"
#include "sha1.h"
#include "sha2.h"
#include "sha3.h"
#include "hash-method.h"

const struct hash_method *hash_method_lookup(const char *name)
{
    unsigned int i;

    for (i = 0; hash_methods[i] != NULL; i++) {
        if (strcmp(hash_methods[i]->name, name) == 0)
            return hash_methods[i];
    }
    return NULL;
}

static void hash_method_init_size(void *context)
{
    uint64_t *ctx = context;

    *ctx = 0;
}

static void
hash_method_loop_size(void *context, const void *data ATTR_UNUSED, size_t size)
{
    uint64_t *ctx = context;

    *ctx += size;
}

static void hash_method_result_size(void *context, unsigned char *result_r)
{
    uint64_t *ctx = context;

    result_r[0] = (*ctx & 0xff00000000000000ULL) >> 56;
    result_r[1] = (*ctx & 0x00ff000000000000ULL) >> 48;
    result_r[2] = (*ctx & 0x0000ff0000000000ULL) >> 40;
    result_r[3] = (*ctx & 0x000000ff00000000ULL) >> 32;
    result_r[4] = (*ctx & 0x00000000ff000000ULL) >> 24;
    result_r[5] = (*ctx & 0x0000000000ff0000ULL) >> 16;
    result_r[6] = (*ctx & 0x000000000000ff00ULL) >> 8;
    result_r[7] = (*ctx & 0x00000000000000ffULL);
}

buffer_t *t_hash_data(const struct hash_method *meth,
              const void *data, size_t data_len)
{
    i_assert(meth != NULL);
    i_assert(data_len == 0 || data != NULL);
    unsigned char ctx[meth->context_size];
    buffer_t *result = buffer_create_dynamic(pool_datastack_create(),
                         meth->digest_size);
    unsigned char *resptr = buffer_append_space_unsafe(result,
                               meth->digest_size);
    meth->init(ctx);
    meth->loop(ctx, data == NULL ? "" : data, data_len);
    meth->result(ctx, resptr);
    return result;
}

static const struct hash_method hash_method_size = {
    "size",
    sizeof(uint64_t),
    sizeof(uint64_t),

    hash_method_init_size,
    hash_method_loop_size,
    hash_method_result_size
};

const struct hash_method *hash_methods[] = {
    &hash_method_md4,
    &hash_method_md5,
    &hash_method_sha1,
    &hash_method_sha256,
    &hash_method_sha512,
    &hash_method_sha3_256,
    &hash_method_sha3_512,
    &hash_method_size,
    NULL
};