From d4ce8327ff902b5ecd42d057063c03793e6d91c2 Mon Sep 17 00:00:00 2001 From: Mattias Andrée Date: Sun, 15 Sep 2024 02:15:08 +0200 Subject: Organise files MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Mattias Andrée --- hmac/libkeccak_hmac_digest.c | 81 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 81 insertions(+) create mode 100644 hmac/libkeccak_hmac_digest.c (limited to 'hmac/libkeccak_hmac_digest.c') diff --git a/hmac/libkeccak_hmac_digest.c b/hmac/libkeccak_hmac_digest.c new file mode 100644 index 0000000..a9e3609 --- /dev/null +++ b/hmac/libkeccak_hmac_digest.c @@ -0,0 +1,81 @@ +/* See LICENSE file for copyright and license details. */ +#define NEED_EXPLICIT_BZERO 1 +#include "../common.h" + + +/** + * Absorb the last part of the message and fetch the hash + * and wipe sensitive data when possible + * + * You may use `&state->sponge` for continued squeezing + * + * @param state The hashing state + * @param msg_ The rest of the message, may be `NULL`, may be modified + * @param msglen The length of the partial message + * @param bits The number of bits at the end of the message not covered by `msglen` + * @param suffix The suffix concatenate to the message, only '1':s and '0':s, and NUL-termination + * @param hashsum Output parameter for the hashsum, may be `NULL` + * @return Zero on success, -1 on error + */ +int +libkeccak_hmac_digest(struct libkeccak_hmac_state *restrict state, const void *restrict msg_, size_t msglen, + size_t bits, const char *restrict suffix, void *restrict hashsum) +{ + const unsigned char *restrict msg = msg_; + size_t hashsize = (size_t)(state->sponge.n >> 3); + char *tmp = malloc((size_t)((state->sponge.n + 7) >> 3) * sizeof(char)); + unsigned char leftover[2]; + size_t newlen; + + if (!tmp) + return -1; + + if (!(state->key_length & 7)) { + if (libkeccak_digest(&state->sponge, msg, msglen, bits, suffix, tmp) < 0) + goto fail; + goto stage_2; + } + + if (libkeccak_hmac_update(state, msg, msglen) < 0) + goto fail; + leftover[0] = state->leftover; + if (bits) { + leftover[0] |= (unsigned char)(msg[msglen] >> (state->key_length & 7)); + leftover[1] = (unsigned char)(msg[msglen] << (8 - (state->key_length & 7))); + } + newlen = (state->key_length & 7) + bits; + if (libkeccak_digest(&state->sponge, leftover, newlen >> 3, newlen & 7, suffix, tmp) < 0) + goto fail; + +stage_2: + bits = state->sponge.n & 7; + state->key_ipad = state->key_opad; + if (libkeccak_hmac_update(state, NULL, 0) < 0) + goto fail; + + if (!(state->key_length & 7)) { + if (libkeccak_digest(&state->sponge, tmp, hashsize, bits, suffix, hashsum) < 0) + goto fail; + goto stage_3; + } + + if (libkeccak_hmac_update(state, tmp, hashsize) < 0) + goto fail; + leftover[0] = state->leftover; + if (bits) { + leftover[0] |= (unsigned char)(tmp[hashsize] >> (state->key_length & 7)); + leftover[1] = (unsigned char)(tmp[hashsize] << (8 - (state->key_length & 7))); + } + newlen = (state->key_length & 7) + bits; + if (libkeccak_digest(&state->sponge, leftover, newlen >> 3, newlen & 7, suffix, tmp) < 0) + goto fail; + +stage_3: + my_explicit_bzero(tmp, (size_t)((state->sponge.n + 7) >> 3) * sizeof(char)); + free(tmp); + return 0; +fail: + my_explicit_bzero(tmp, (size_t)((state->sponge.n + 7) >> 3) * sizeof(char)); + free(tmp); + return -1; +} -- cgit v1.2.3-70-g09d2