| /*********************************************************************** |
| ** |
| ** Implementation of the Skein hash function. |
| ** |
| ** Source code author: Doug Whiting, 2008. |
| ** |
| ** This algorithm and source code is released to the public domain. |
| ** |
| ************************************************************************/ |
| |
| #include <linux/string.h> /* get the memcpy/memset functions */ |
| #include <linux/export.h> |
| #include "skein_base.h" /* get the Skein API definitions */ |
| #include "skein_iv.h" /* get precomputed IVs */ |
| #include "skein_block.h" |
| |
| /*****************************************************************/ |
| /* 256-bit Skein */ |
| /*****************************************************************/ |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* init the context for a straight hashing operation */ |
| int skein_256_init(struct skein_256_ctx *ctx, size_t hash_bit_len) |
| { |
| union { |
| u8 b[SKEIN_256_STATE_BYTES]; |
| u64 w[SKEIN_256_STATE_WORDS]; |
| } cfg; /* config block */ |
| |
| skein_assert_ret(hash_bit_len > 0, SKEIN_BAD_HASHLEN); |
| ctx->h.hash_bit_len = hash_bit_len; /* output hash bit count */ |
| |
| switch (hash_bit_len) { /* use pre-computed values, where available */ |
| case 256: |
| memcpy(ctx->x, SKEIN_256_IV_256, sizeof(ctx->x)); |
| break; |
| case 224: |
| memcpy(ctx->x, SKEIN_256_IV_224, sizeof(ctx->x)); |
| break; |
| case 160: |
| memcpy(ctx->x, SKEIN_256_IV_160, sizeof(ctx->x)); |
| break; |
| case 128: |
| memcpy(ctx->x, SKEIN_256_IV_128, sizeof(ctx->x)); |
| break; |
| default: |
| /* here if there is no precomputed IV value available */ |
| /* |
| * build/process the config block, type == CONFIG (could be |
| * precomputed) |
| */ |
| /* set tweaks: T0=0; T1=CFG | FINAL */ |
| skein_start_new_type(ctx, CFG_FINAL); |
| |
| /* set the schema, version */ |
| cfg.w[0] = skein_swap64(SKEIN_SCHEMA_VER); |
| /* hash result length in bits */ |
| cfg.w[1] = skein_swap64(hash_bit_len); |
| cfg.w[2] = skein_swap64(SKEIN_CFG_TREE_INFO_SEQUENTIAL); |
| /* zero pad config block */ |
| memset(&cfg.w[3], 0, sizeof(cfg) - 3*sizeof(cfg.w[0])); |
| |
| /* compute the initial chaining values from config block */ |
| /* zero the chaining variables */ |
| memset(ctx->x, 0, sizeof(ctx->x)); |
| skein_256_process_block(ctx, cfg.b, 1, SKEIN_CFG_STR_LEN); |
| break; |
| } |
| /* The chaining vars ctx->x are now initialized for hash_bit_len. */ |
| /* Set up to process the data message portion of the hash (default) */ |
| skein_start_new_type(ctx, MSG); /* T0=0, T1= MSG type */ |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* init the context for a MAC and/or tree hash operation */ |
| /* |
| * [identical to skein_256_init() when key_bytes == 0 && \ |
| * tree_info == SKEIN_CFG_TREE_INFO_SEQUENTIAL] |
| */ |
| int skein_256_init_ext(struct skein_256_ctx *ctx, size_t hash_bit_len, |
| u64 tree_info, const u8 *key, size_t key_bytes) |
| { |
| union { |
| u8 b[SKEIN_256_STATE_BYTES]; |
| u64 w[SKEIN_256_STATE_WORDS]; |
| } cfg; /* config block */ |
| |
| skein_assert_ret(hash_bit_len > 0, SKEIN_BAD_HASHLEN); |
| skein_assert_ret(key_bytes == 0 || key, SKEIN_FAIL); |
| |
| /* compute the initial chaining values ctx->x[], based on key */ |
| if (key_bytes == 0) { /* is there a key? */ |
| /* no key: use all zeroes as key for config block */ |
| memset(ctx->x, 0, sizeof(ctx->x)); |
| } else { /* here to pre-process a key */ |
| skein_assert(sizeof(cfg.b) >= sizeof(ctx->x)); |
| /* do a mini-Init right here */ |
| /* set output hash bit count = state size */ |
| ctx->h.hash_bit_len = 8*sizeof(ctx->x); |
| /* set tweaks: T0 = 0; T1 = KEY type */ |
| skein_start_new_type(ctx, KEY); |
| /* zero the initial chaining variables */ |
| memset(ctx->x, 0, sizeof(ctx->x)); |
| /* hash the key */ |
| skein_256_update(ctx, key, key_bytes); |
| /* put result into cfg.b[] */ |
| skein_256_final_pad(ctx, cfg.b); |
| /* copy over into ctx->x[] */ |
| memcpy(ctx->x, cfg.b, sizeof(cfg.b)); |
| } |
| /* |
| * build/process the config block, type == CONFIG (could be |
| * precomputed for each key) |
| */ |
| /* output hash bit count */ |
| ctx->h.hash_bit_len = hash_bit_len; |
| skein_start_new_type(ctx, CFG_FINAL); |
| |
| /* pre-pad cfg.w[] with zeroes */ |
| memset(&cfg.w, 0, sizeof(cfg.w)); |
| cfg.w[0] = skein_swap64(SKEIN_SCHEMA_VER); |
| /* hash result length in bits */ |
| cfg.w[1] = skein_swap64(hash_bit_len); |
| /* tree hash config info (or SKEIN_CFG_TREE_INFO_SEQUENTIAL) */ |
| cfg.w[2] = skein_swap64(tree_info); |
| |
| /* compute the initial chaining values from config block */ |
| skein_256_process_block(ctx, cfg.b, 1, SKEIN_CFG_STR_LEN); |
| |
| /* The chaining vars ctx->x are now initialized */ |
| /* Set up to process the data message portion of the hash (default) */ |
| skein_start_new_type(ctx, MSG); |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* process the input bytes */ |
| int skein_256_update(struct skein_256_ctx *ctx, const u8 *msg, |
| size_t msg_byte_cnt) |
| { |
| size_t n; |
| |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_256_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* process full blocks, if any */ |
| if (msg_byte_cnt + ctx->h.b_cnt > SKEIN_256_BLOCK_BYTES) { |
| /* finish up any buffered message data */ |
| if (ctx->h.b_cnt) { |
| /* # bytes free in buffer b[] */ |
| n = SKEIN_256_BLOCK_BYTES - ctx->h.b_cnt; |
| if (n) { |
| /* check on our logic here */ |
| skein_assert(n < msg_byte_cnt); |
| memcpy(&ctx->b[ctx->h.b_cnt], msg, n); |
| msg_byte_cnt -= n; |
| msg += n; |
| ctx->h.b_cnt += n; |
| } |
| skein_assert(ctx->h.b_cnt == SKEIN_256_BLOCK_BYTES); |
| skein_256_process_block(ctx, ctx->b, 1, |
| SKEIN_256_BLOCK_BYTES); |
| ctx->h.b_cnt = 0; |
| } |
| /* |
| * now process any remaining full blocks, directly from input |
| * message data |
| */ |
| if (msg_byte_cnt > SKEIN_256_BLOCK_BYTES) { |
| /* number of full blocks to process */ |
| n = (msg_byte_cnt-1) / SKEIN_256_BLOCK_BYTES; |
| skein_256_process_block(ctx, msg, n, |
| SKEIN_256_BLOCK_BYTES); |
| msg_byte_cnt -= n * SKEIN_256_BLOCK_BYTES; |
| msg += n * SKEIN_256_BLOCK_BYTES; |
| } |
| skein_assert(ctx->h.b_cnt == 0); |
| } |
| |
| /* copy any remaining source message data bytes into b[] */ |
| if (msg_byte_cnt) { |
| skein_assert(msg_byte_cnt + ctx->h.b_cnt <= |
| SKEIN_256_BLOCK_BYTES); |
| memcpy(&ctx->b[ctx->h.b_cnt], msg, msg_byte_cnt); |
| ctx->h.b_cnt += msg_byte_cnt; |
| } |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* finalize the hash computation and output the result */ |
| int skein_256_final(struct skein_256_ctx *ctx, u8 *hash_val) |
| { |
| size_t i, n, byte_cnt; |
| u64 x[SKEIN_256_STATE_WORDS]; |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_256_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* tag as the final block */ |
| ctx->h.tweak[1] |= SKEIN_T1_FLAG_FINAL; |
| /* zero pad b[] if necessary */ |
| if (ctx->h.b_cnt < SKEIN_256_BLOCK_BYTES) |
| memset(&ctx->b[ctx->h.b_cnt], 0, |
| SKEIN_256_BLOCK_BYTES - ctx->h.b_cnt); |
| |
| /* process the final block */ |
| skein_256_process_block(ctx, ctx->b, 1, ctx->h.b_cnt); |
| |
| /* now output the result */ |
| /* total number of output bytes */ |
| byte_cnt = (ctx->h.hash_bit_len + 7) >> 3; |
| |
| /* run Threefish in "counter mode" to generate output */ |
| /* zero out b[], so it can hold the counter */ |
| memset(ctx->b, 0, sizeof(ctx->b)); |
| /* keep a local copy of counter mode "key" */ |
| memcpy(x, ctx->x, sizeof(x)); |
| for (i = 0; i*SKEIN_256_BLOCK_BYTES < byte_cnt; i++) { |
| /* build the counter block */ |
| ((u64 *)ctx->b)[0] = skein_swap64((u64) i); |
| skein_start_new_type(ctx, OUT_FINAL); |
| /* run "counter mode" */ |
| skein_256_process_block(ctx, ctx->b, 1, sizeof(u64)); |
| /* number of output bytes left to go */ |
| n = byte_cnt - i*SKEIN_256_BLOCK_BYTES; |
| if (n >= SKEIN_256_BLOCK_BYTES) |
| n = SKEIN_256_BLOCK_BYTES; |
| /* "output" the ctr mode bytes */ |
| skein_put64_lsb_first(hash_val+i*SKEIN_256_BLOCK_BYTES, ctx->x, |
| n); |
| /* restore the counter mode key for next time */ |
| memcpy(ctx->x, x, sizeof(x)); |
| } |
| return SKEIN_SUCCESS; |
| } |
| |
| /*****************************************************************/ |
| /* 512-bit Skein */ |
| /*****************************************************************/ |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* init the context for a straight hashing operation */ |
| int skein_512_init(struct skein_512_ctx *ctx, size_t hash_bit_len) |
| { |
| union { |
| u8 b[SKEIN_512_STATE_BYTES]; |
| u64 w[SKEIN_512_STATE_WORDS]; |
| } cfg; /* config block */ |
| |
| skein_assert_ret(hash_bit_len > 0, SKEIN_BAD_HASHLEN); |
| ctx->h.hash_bit_len = hash_bit_len; /* output hash bit count */ |
| |
| switch (hash_bit_len) { /* use pre-computed values, where available */ |
| case 512: |
| memcpy(ctx->x, SKEIN_512_IV_512, sizeof(ctx->x)); |
| break; |
| case 384: |
| memcpy(ctx->x, SKEIN_512_IV_384, sizeof(ctx->x)); |
| break; |
| case 256: |
| memcpy(ctx->x, SKEIN_512_IV_256, sizeof(ctx->x)); |
| break; |
| case 224: |
| memcpy(ctx->x, SKEIN_512_IV_224, sizeof(ctx->x)); |
| break; |
| default: |
| /* here if there is no precomputed IV value available */ |
| /* |
| * build/process the config block, type == CONFIG (could be |
| * precomputed) |
| */ |
| /* set tweaks: T0=0; T1=CFG | FINAL */ |
| skein_start_new_type(ctx, CFG_FINAL); |
| |
| /* set the schema, version */ |
| cfg.w[0] = skein_swap64(SKEIN_SCHEMA_VER); |
| /* hash result length in bits */ |
| cfg.w[1] = skein_swap64(hash_bit_len); |
| cfg.w[2] = skein_swap64(SKEIN_CFG_TREE_INFO_SEQUENTIAL); |
| /* zero pad config block */ |
| memset(&cfg.w[3], 0, sizeof(cfg) - 3*sizeof(cfg.w[0])); |
| |
| /* compute the initial chaining values from config block */ |
| /* zero the chaining variables */ |
| memset(ctx->x, 0, sizeof(ctx->x)); |
| skein_512_process_block(ctx, cfg.b, 1, SKEIN_CFG_STR_LEN); |
| break; |
| } |
| |
| /* |
| * The chaining vars ctx->x are now initialized for the given |
| * hash_bit_len. |
| */ |
| /* Set up to process the data message portion of the hash (default) */ |
| skein_start_new_type(ctx, MSG); /* T0=0, T1= MSG type */ |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* init the context for a MAC and/or tree hash operation */ |
| /* |
| * [identical to skein_512_init() when key_bytes == 0 && \ |
| * tree_info == SKEIN_CFG_TREE_INFO_SEQUENTIAL] |
| */ |
| int skein_512_init_ext(struct skein_512_ctx *ctx, size_t hash_bit_len, |
| u64 tree_info, const u8 *key, size_t key_bytes) |
| { |
| union { |
| u8 b[SKEIN_512_STATE_BYTES]; |
| u64 w[SKEIN_512_STATE_WORDS]; |
| } cfg; /* config block */ |
| |
| skein_assert_ret(hash_bit_len > 0, SKEIN_BAD_HASHLEN); |
| skein_assert_ret(key_bytes == 0 || key, SKEIN_FAIL); |
| |
| /* compute the initial chaining values ctx->x[], based on key */ |
| if (key_bytes == 0) { /* is there a key? */ |
| /* no key: use all zeroes as key for config block */ |
| memset(ctx->x, 0, sizeof(ctx->x)); |
| } else { /* here to pre-process a key */ |
| skein_assert(sizeof(cfg.b) >= sizeof(ctx->x)); |
| /* do a mini-Init right here */ |
| /* set output hash bit count = state size */ |
| ctx->h.hash_bit_len = 8*sizeof(ctx->x); |
| /* set tweaks: T0 = 0; T1 = KEY type */ |
| skein_start_new_type(ctx, KEY); |
| /* zero the initial chaining variables */ |
| memset(ctx->x, 0, sizeof(ctx->x)); |
| /* hash the key */ |
| skein_512_update(ctx, key, key_bytes); |
| /* put result into cfg.b[] */ |
| skein_512_final_pad(ctx, cfg.b); |
| /* copy over into ctx->x[] */ |
| memcpy(ctx->x, cfg.b, sizeof(cfg.b)); |
| } |
| /* |
| * build/process the config block, type == CONFIG (could be |
| * precomputed for each key) |
| */ |
| ctx->h.hash_bit_len = hash_bit_len; /* output hash bit count */ |
| skein_start_new_type(ctx, CFG_FINAL); |
| |
| /* pre-pad cfg.w[] with zeroes */ |
| memset(&cfg.w, 0, sizeof(cfg.w)); |
| cfg.w[0] = skein_swap64(SKEIN_SCHEMA_VER); |
| /* hash result length in bits */ |
| cfg.w[1] = skein_swap64(hash_bit_len); |
| /* tree hash config info (or SKEIN_CFG_TREE_INFO_SEQUENTIAL) */ |
| cfg.w[2] = skein_swap64(tree_info); |
| |
| /* compute the initial chaining values from config block */ |
| skein_512_process_block(ctx, cfg.b, 1, SKEIN_CFG_STR_LEN); |
| |
| /* The chaining vars ctx->x are now initialized */ |
| /* Set up to process the data message portion of the hash (default) */ |
| skein_start_new_type(ctx, MSG); |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* process the input bytes */ |
| int skein_512_update(struct skein_512_ctx *ctx, const u8 *msg, |
| size_t msg_byte_cnt) |
| { |
| size_t n; |
| |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_512_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* process full blocks, if any */ |
| if (msg_byte_cnt + ctx->h.b_cnt > SKEIN_512_BLOCK_BYTES) { |
| /* finish up any buffered message data */ |
| if (ctx->h.b_cnt) { |
| /* # bytes free in buffer b[] */ |
| n = SKEIN_512_BLOCK_BYTES - ctx->h.b_cnt; |
| if (n) { |
| /* check on our logic here */ |
| skein_assert(n < msg_byte_cnt); |
| memcpy(&ctx->b[ctx->h.b_cnt], msg, n); |
| msg_byte_cnt -= n; |
| msg += n; |
| ctx->h.b_cnt += n; |
| } |
| skein_assert(ctx->h.b_cnt == SKEIN_512_BLOCK_BYTES); |
| skein_512_process_block(ctx, ctx->b, 1, |
| SKEIN_512_BLOCK_BYTES); |
| ctx->h.b_cnt = 0; |
| } |
| /* |
| * now process any remaining full blocks, directly from input |
| * message data |
| */ |
| if (msg_byte_cnt > SKEIN_512_BLOCK_BYTES) { |
| /* number of full blocks to process */ |
| n = (msg_byte_cnt-1) / SKEIN_512_BLOCK_BYTES; |
| skein_512_process_block(ctx, msg, n, |
| SKEIN_512_BLOCK_BYTES); |
| msg_byte_cnt -= n * SKEIN_512_BLOCK_BYTES; |
| msg += n * SKEIN_512_BLOCK_BYTES; |
| } |
| skein_assert(ctx->h.b_cnt == 0); |
| } |
| |
| /* copy any remaining source message data bytes into b[] */ |
| if (msg_byte_cnt) { |
| skein_assert(msg_byte_cnt + ctx->h.b_cnt <= |
| SKEIN_512_BLOCK_BYTES); |
| memcpy(&ctx->b[ctx->h.b_cnt], msg, msg_byte_cnt); |
| ctx->h.b_cnt += msg_byte_cnt; |
| } |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* finalize the hash computation and output the result */ |
| int skein_512_final(struct skein_512_ctx *ctx, u8 *hash_val) |
| { |
| size_t i, n, byte_cnt; |
| u64 x[SKEIN_512_STATE_WORDS]; |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_512_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* tag as the final block */ |
| ctx->h.tweak[1] |= SKEIN_T1_FLAG_FINAL; |
| /* zero pad b[] if necessary */ |
| if (ctx->h.b_cnt < SKEIN_512_BLOCK_BYTES) |
| memset(&ctx->b[ctx->h.b_cnt], 0, |
| SKEIN_512_BLOCK_BYTES - ctx->h.b_cnt); |
| |
| /* process the final block */ |
| skein_512_process_block(ctx, ctx->b, 1, ctx->h.b_cnt); |
| |
| /* now output the result */ |
| /* total number of output bytes */ |
| byte_cnt = (ctx->h.hash_bit_len + 7) >> 3; |
| |
| /* run Threefish in "counter mode" to generate output */ |
| /* zero out b[], so it can hold the counter */ |
| memset(ctx->b, 0, sizeof(ctx->b)); |
| /* keep a local copy of counter mode "key" */ |
| memcpy(x, ctx->x, sizeof(x)); |
| for (i = 0; i*SKEIN_512_BLOCK_BYTES < byte_cnt; i++) { |
| /* build the counter block */ |
| ((u64 *)ctx->b)[0] = skein_swap64((u64) i); |
| skein_start_new_type(ctx, OUT_FINAL); |
| /* run "counter mode" */ |
| skein_512_process_block(ctx, ctx->b, 1, sizeof(u64)); |
| /* number of output bytes left to go */ |
| n = byte_cnt - i*SKEIN_512_BLOCK_BYTES; |
| if (n >= SKEIN_512_BLOCK_BYTES) |
| n = SKEIN_512_BLOCK_BYTES; |
| /* "output" the ctr mode bytes */ |
| skein_put64_lsb_first(hash_val+i*SKEIN_512_BLOCK_BYTES, ctx->x, |
| n); |
| /* restore the counter mode key for next time */ |
| memcpy(ctx->x, x, sizeof(x)); |
| } |
| return SKEIN_SUCCESS; |
| } |
| |
| /*****************************************************************/ |
| /* 1024-bit Skein */ |
| /*****************************************************************/ |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* init the context for a straight hashing operation */ |
| int skein_1024_init(struct skein_1024_ctx *ctx, size_t hash_bit_len) |
| { |
| union { |
| u8 b[SKEIN_1024_STATE_BYTES]; |
| u64 w[SKEIN_1024_STATE_WORDS]; |
| } cfg; /* config block */ |
| |
| skein_assert_ret(hash_bit_len > 0, SKEIN_BAD_HASHLEN); |
| ctx->h.hash_bit_len = hash_bit_len; /* output hash bit count */ |
| |
| switch (hash_bit_len) { /* use pre-computed values, where available */ |
| case 512: |
| memcpy(ctx->x, SKEIN_1024_IV_512, sizeof(ctx->x)); |
| break; |
| case 384: |
| memcpy(ctx->x, SKEIN_1024_IV_384, sizeof(ctx->x)); |
| break; |
| case 1024: |
| memcpy(ctx->x, SKEIN_1024_IV_1024, sizeof(ctx->x)); |
| break; |
| default: |
| /* here if there is no precomputed IV value available */ |
| /* |
| * build/process the config block, type == CONFIG |
| * (could be precomputed) |
| */ |
| /* set tweaks: T0=0; T1=CFG | FINAL */ |
| skein_start_new_type(ctx, CFG_FINAL); |
| |
| /* set the schema, version */ |
| cfg.w[0] = skein_swap64(SKEIN_SCHEMA_VER); |
| /* hash result length in bits */ |
| cfg.w[1] = skein_swap64(hash_bit_len); |
| cfg.w[2] = skein_swap64(SKEIN_CFG_TREE_INFO_SEQUENTIAL); |
| /* zero pad config block */ |
| memset(&cfg.w[3], 0, sizeof(cfg) - 3*sizeof(cfg.w[0])); |
| |
| /* compute the initial chaining values from config block */ |
| /* zero the chaining variables */ |
| memset(ctx->x, 0, sizeof(ctx->x)); |
| skein_1024_process_block(ctx, cfg.b, 1, SKEIN_CFG_STR_LEN); |
| break; |
| } |
| |
| /* The chaining vars ctx->x are now initialized for the hash_bit_len. */ |
| /* Set up to process the data message portion of the hash (default) */ |
| skein_start_new_type(ctx, MSG); /* T0=0, T1= MSG type */ |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* init the context for a MAC and/or tree hash operation */ |
| /* |
| * [identical to skein_1024_init() when key_bytes == 0 && \ |
| * tree_info == SKEIN_CFG_TREE_INFO_SEQUENTIAL] |
| */ |
| int skein_1024_init_ext(struct skein_1024_ctx *ctx, size_t hash_bit_len, |
| u64 tree_info, const u8 *key, size_t key_bytes) |
| { |
| union { |
| u8 b[SKEIN_1024_STATE_BYTES]; |
| u64 w[SKEIN_1024_STATE_WORDS]; |
| } cfg; /* config block */ |
| |
| skein_assert_ret(hash_bit_len > 0, SKEIN_BAD_HASHLEN); |
| skein_assert_ret(key_bytes == 0 || key, SKEIN_FAIL); |
| |
| /* compute the initial chaining values ctx->x[], based on key */ |
| if (key_bytes == 0) { /* is there a key? */ |
| /* no key: use all zeroes as key for config block */ |
| memset(ctx->x, 0, sizeof(ctx->x)); |
| } else { /* here to pre-process a key */ |
| skein_assert(sizeof(cfg.b) >= sizeof(ctx->x)); |
| /* do a mini-Init right here */ |
| /* set output hash bit count = state size */ |
| ctx->h.hash_bit_len = 8*sizeof(ctx->x); |
| /* set tweaks: T0 = 0; T1 = KEY type */ |
| skein_start_new_type(ctx, KEY); |
| /* zero the initial chaining variables */ |
| memset(ctx->x, 0, sizeof(ctx->x)); |
| /* hash the key */ |
| skein_1024_update(ctx, key, key_bytes); |
| /* put result into cfg.b[] */ |
| skein_1024_final_pad(ctx, cfg.b); |
| /* copy over into ctx->x[] */ |
| memcpy(ctx->x, cfg.b, sizeof(cfg.b)); |
| } |
| /* |
| * build/process the config block, type == CONFIG (could be |
| * precomputed for each key) |
| */ |
| /* output hash bit count */ |
| ctx->h.hash_bit_len = hash_bit_len; |
| skein_start_new_type(ctx, CFG_FINAL); |
| |
| /* pre-pad cfg.w[] with zeroes */ |
| memset(&cfg.w, 0, sizeof(cfg.w)); |
| cfg.w[0] = skein_swap64(SKEIN_SCHEMA_VER); |
| /* hash result length in bits */ |
| cfg.w[1] = skein_swap64(hash_bit_len); |
| /* tree hash config info (or SKEIN_CFG_TREE_INFO_SEQUENTIAL) */ |
| cfg.w[2] = skein_swap64(tree_info); |
| |
| /* compute the initial chaining values from config block */ |
| skein_1024_process_block(ctx, cfg.b, 1, SKEIN_CFG_STR_LEN); |
| |
| /* The chaining vars ctx->x are now initialized */ |
| /* Set up to process the data message portion of the hash (default) */ |
| skein_start_new_type(ctx, MSG); |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* process the input bytes */ |
| int skein_1024_update(struct skein_1024_ctx *ctx, const u8 *msg, |
| size_t msg_byte_cnt) |
| { |
| size_t n; |
| |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_1024_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* process full blocks, if any */ |
| if (msg_byte_cnt + ctx->h.b_cnt > SKEIN_1024_BLOCK_BYTES) { |
| /* finish up any buffered message data */ |
| if (ctx->h.b_cnt) { |
| /* # bytes free in buffer b[] */ |
| n = SKEIN_1024_BLOCK_BYTES - ctx->h.b_cnt; |
| if (n) { |
| /* check on our logic here */ |
| skein_assert(n < msg_byte_cnt); |
| memcpy(&ctx->b[ctx->h.b_cnt], msg, n); |
| msg_byte_cnt -= n; |
| msg += n; |
| ctx->h.b_cnt += n; |
| } |
| skein_assert(ctx->h.b_cnt == SKEIN_1024_BLOCK_BYTES); |
| skein_1024_process_block(ctx, ctx->b, 1, |
| SKEIN_1024_BLOCK_BYTES); |
| ctx->h.b_cnt = 0; |
| } |
| /* |
| * now process any remaining full blocks, directly from input |
| * message data |
| */ |
| if (msg_byte_cnt > SKEIN_1024_BLOCK_BYTES) { |
| /* number of full blocks to process */ |
| n = (msg_byte_cnt-1) / SKEIN_1024_BLOCK_BYTES; |
| skein_1024_process_block(ctx, msg, n, |
| SKEIN_1024_BLOCK_BYTES); |
| msg_byte_cnt -= n * SKEIN_1024_BLOCK_BYTES; |
| msg += n * SKEIN_1024_BLOCK_BYTES; |
| } |
| skein_assert(ctx->h.b_cnt == 0); |
| } |
| |
| /* copy any remaining source message data bytes into b[] */ |
| if (msg_byte_cnt) { |
| skein_assert(msg_byte_cnt + ctx->h.b_cnt <= |
| SKEIN_1024_BLOCK_BYTES); |
| memcpy(&ctx->b[ctx->h.b_cnt], msg, msg_byte_cnt); |
| ctx->h.b_cnt += msg_byte_cnt; |
| } |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* finalize the hash computation and output the result */ |
| int skein_1024_final(struct skein_1024_ctx *ctx, u8 *hash_val) |
| { |
| size_t i, n, byte_cnt; |
| u64 x[SKEIN_1024_STATE_WORDS]; |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_1024_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* tag as the final block */ |
| ctx->h.tweak[1] |= SKEIN_T1_FLAG_FINAL; |
| /* zero pad b[] if necessary */ |
| if (ctx->h.b_cnt < SKEIN_1024_BLOCK_BYTES) |
| memset(&ctx->b[ctx->h.b_cnt], 0, |
| SKEIN_1024_BLOCK_BYTES - ctx->h.b_cnt); |
| |
| /* process the final block */ |
| skein_1024_process_block(ctx, ctx->b, 1, ctx->h.b_cnt); |
| |
| /* now output the result */ |
| /* total number of output bytes */ |
| byte_cnt = (ctx->h.hash_bit_len + 7) >> 3; |
| |
| /* run Threefish in "counter mode" to generate output */ |
| /* zero out b[], so it can hold the counter */ |
| memset(ctx->b, 0, sizeof(ctx->b)); |
| /* keep a local copy of counter mode "key" */ |
| memcpy(x, ctx->x, sizeof(x)); |
| for (i = 0; i*SKEIN_1024_BLOCK_BYTES < byte_cnt; i++) { |
| /* build the counter block */ |
| ((u64 *)ctx->b)[0] = skein_swap64((u64) i); |
| skein_start_new_type(ctx, OUT_FINAL); |
| /* run "counter mode" */ |
| skein_1024_process_block(ctx, ctx->b, 1, sizeof(u64)); |
| /* number of output bytes left to go */ |
| n = byte_cnt - i*SKEIN_1024_BLOCK_BYTES; |
| if (n >= SKEIN_1024_BLOCK_BYTES) |
| n = SKEIN_1024_BLOCK_BYTES; |
| /* "output" the ctr mode bytes */ |
| skein_put64_lsb_first(hash_val+i*SKEIN_1024_BLOCK_BYTES, ctx->x, |
| n); |
| /* restore the counter mode key for next time */ |
| memcpy(ctx->x, x, sizeof(x)); |
| } |
| return SKEIN_SUCCESS; |
| } |
| |
| /**************** Functions to support MAC/tree hashing ***************/ |
| /* (this code is identical for Optimized and Reference versions) */ |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* finalize the hash computation and output the block, no OUTPUT stage */ |
| int skein_256_final_pad(struct skein_256_ctx *ctx, u8 *hash_val) |
| { |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_256_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* tag as the final block */ |
| ctx->h.tweak[1] |= SKEIN_T1_FLAG_FINAL; |
| /* zero pad b[] if necessary */ |
| if (ctx->h.b_cnt < SKEIN_256_BLOCK_BYTES) |
| memset(&ctx->b[ctx->h.b_cnt], 0, |
| SKEIN_256_BLOCK_BYTES - ctx->h.b_cnt); |
| /* process the final block */ |
| skein_256_process_block(ctx, ctx->b, 1, ctx->h.b_cnt); |
| |
| /* "output" the state bytes */ |
| skein_put64_lsb_first(hash_val, ctx->x, SKEIN_256_BLOCK_BYTES); |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* finalize the hash computation and output the block, no OUTPUT stage */ |
| int skein_512_final_pad(struct skein_512_ctx *ctx, u8 *hash_val) |
| { |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_512_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* tag as the final block */ |
| ctx->h.tweak[1] |= SKEIN_T1_FLAG_FINAL; |
| /* zero pad b[] if necessary */ |
| if (ctx->h.b_cnt < SKEIN_512_BLOCK_BYTES) |
| memset(&ctx->b[ctx->h.b_cnt], 0, |
| SKEIN_512_BLOCK_BYTES - ctx->h.b_cnt); |
| /* process the final block */ |
| skein_512_process_block(ctx, ctx->b, 1, ctx->h.b_cnt); |
| |
| /* "output" the state bytes */ |
| skein_put64_lsb_first(hash_val, ctx->x, SKEIN_512_BLOCK_BYTES); |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* finalize the hash computation and output the block, no OUTPUT stage */ |
| int skein_1024_final_pad(struct skein_1024_ctx *ctx, u8 *hash_val) |
| { |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_1024_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* tag as the final block */ |
| ctx->h.tweak[1] |= SKEIN_T1_FLAG_FINAL; |
| /* zero pad b[] if necessary */ |
| if (ctx->h.b_cnt < SKEIN_1024_BLOCK_BYTES) |
| memset(&ctx->b[ctx->h.b_cnt], 0, |
| SKEIN_1024_BLOCK_BYTES - ctx->h.b_cnt); |
| /* process the final block */ |
| skein_1024_process_block(ctx, ctx->b, 1, ctx->h.b_cnt); |
| |
| /* "output" the state bytes */ |
| skein_put64_lsb_first(hash_val, ctx->x, SKEIN_1024_BLOCK_BYTES); |
| |
| return SKEIN_SUCCESS; |
| } |
| |
| #if SKEIN_TREE_HASH |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* just do the OUTPUT stage */ |
| int skein_256_output(struct skein_256_ctx *ctx, u8 *hash_val) |
| { |
| size_t i, n, byte_cnt; |
| u64 x[SKEIN_256_STATE_WORDS]; |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_256_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* now output the result */ |
| /* total number of output bytes */ |
| byte_cnt = (ctx->h.hash_bit_len + 7) >> 3; |
| |
| /* run Threefish in "counter mode" to generate output */ |
| /* zero out b[], so it can hold the counter */ |
| memset(ctx->b, 0, sizeof(ctx->b)); |
| /* keep a local copy of counter mode "key" */ |
| memcpy(x, ctx->x, sizeof(x)); |
| for (i = 0; i*SKEIN_256_BLOCK_BYTES < byte_cnt; i++) { |
| /* build the counter block */ |
| ((u64 *)ctx->b)[0] = skein_swap64((u64) i); |
| skein_start_new_type(ctx, OUT_FINAL); |
| /* run "counter mode" */ |
| skein_256_process_block(ctx, ctx->b, 1, sizeof(u64)); |
| /* number of output bytes left to go */ |
| n = byte_cnt - i*SKEIN_256_BLOCK_BYTES; |
| if (n >= SKEIN_256_BLOCK_BYTES) |
| n = SKEIN_256_BLOCK_BYTES; |
| /* "output" the ctr mode bytes */ |
| skein_put64_lsb_first(hash_val+i*SKEIN_256_BLOCK_BYTES, ctx->x, |
| n); |
| /* restore the counter mode key for next time */ |
| memcpy(ctx->x, x, sizeof(x)); |
| } |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* just do the OUTPUT stage */ |
| int skein_512_output(struct skein_512_ctx *ctx, u8 *hash_val) |
| { |
| size_t i, n, byte_cnt; |
| u64 x[SKEIN_512_STATE_WORDS]; |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_512_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* now output the result */ |
| /* total number of output bytes */ |
| byte_cnt = (ctx->h.hash_bit_len + 7) >> 3; |
| |
| /* run Threefish in "counter mode" to generate output */ |
| /* zero out b[], so it can hold the counter */ |
| memset(ctx->b, 0, sizeof(ctx->b)); |
| /* keep a local copy of counter mode "key" */ |
| memcpy(x, ctx->x, sizeof(x)); |
| for (i = 0; i*SKEIN_512_BLOCK_BYTES < byte_cnt; i++) { |
| /* build the counter block */ |
| ((u64 *)ctx->b)[0] = skein_swap64((u64) i); |
| skein_start_new_type(ctx, OUT_FINAL); |
| /* run "counter mode" */ |
| skein_512_process_block(ctx, ctx->b, 1, sizeof(u64)); |
| /* number of output bytes left to go */ |
| n = byte_cnt - i*SKEIN_512_BLOCK_BYTES; |
| if (n >= SKEIN_512_BLOCK_BYTES) |
| n = SKEIN_512_BLOCK_BYTES; |
| /* "output" the ctr mode bytes */ |
| skein_put64_lsb_first(hash_val+i*SKEIN_512_BLOCK_BYTES, ctx->x, |
| n); |
| /* restore the counter mode key for next time */ |
| memcpy(ctx->x, x, sizeof(x)); |
| } |
| return SKEIN_SUCCESS; |
| } |
| |
| /*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/ |
| /* just do the OUTPUT stage */ |
| int skein_1024_output(struct skein_1024_ctx *ctx, u8 *hash_val) |
| { |
| size_t i, n, byte_cnt; |
| u64 x[SKEIN_1024_STATE_WORDS]; |
| /* catch uninitialized context */ |
| skein_assert_ret(ctx->h.b_cnt <= SKEIN_1024_BLOCK_BYTES, SKEIN_FAIL); |
| |
| /* now output the result */ |
| /* total number of output bytes */ |
| byte_cnt = (ctx->h.hash_bit_len + 7) >> 3; |
| |
| /* run Threefish in "counter mode" to generate output */ |
| /* zero out b[], so it can hold the counter */ |
| memset(ctx->b, 0, sizeof(ctx->b)); |
| /* keep a local copy of counter mode "key" */ |
| memcpy(x, ctx->x, sizeof(x)); |
| for (i = 0; i*SKEIN_1024_BLOCK_BYTES < byte_cnt; i++) { |
| /* build the counter block */ |
| ((u64 *)ctx->b)[0] = skein_swap64((u64) i); |
| skein_start_new_type(ctx, OUT_FINAL); |
| /* run "counter mode" */ |
| skein_1024_process_block(ctx, ctx->b, 1, sizeof(u64)); |
| /* number of output bytes left to go */ |
| n = byte_cnt - i*SKEIN_1024_BLOCK_BYTES; |
| if (n >= SKEIN_1024_BLOCK_BYTES) |
| n = SKEIN_1024_BLOCK_BYTES; |
| /* "output" the ctr mode bytes */ |
| skein_put64_lsb_first(hash_val+i*SKEIN_1024_BLOCK_BYTES, ctx->x, |
| n); |
| /* restore the counter mode key for next time */ |
| memcpy(ctx->x, x, sizeof(x)); |
| } |
| return SKEIN_SUCCESS; |
| } |
| #endif |