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-rw-r--r--Cryptlib/OpenSSL/crypto/modes/ocb128.c568
1 files changed, 0 insertions, 568 deletions
diff --git a/Cryptlib/OpenSSL/crypto/modes/ocb128.c b/Cryptlib/OpenSSL/crypto/modes/ocb128.c
deleted file mode 100644
index c3bd13bb..00000000
--- a/Cryptlib/OpenSSL/crypto/modes/ocb128.c
+++ /dev/null
@@ -1,568 +0,0 @@
-/*
- * Copyright 2014-2016 The OpenSSL Project Authors. All Rights Reserved.
- *
- * Licensed under the OpenSSL license (the "License"). You may not use
- * this file except in compliance with the License. You can obtain a copy
- * in the file LICENSE in the source distribution or at
- * https://www.openssl.org/source/license.html
- */
-
-#include <string.h>
-#include <openssl/crypto.h>
-#include "modes_lcl.h"
-
-#ifndef OPENSSL_NO_OCB
-
-/*
- * Calculate the number of binary trailing zero's in any given number
- */
-static u32 ocb_ntz(u64 n)
-{
- u32 cnt = 0;
-
- /*
- * We do a right-to-left simple sequential search. This is surprisingly
- * efficient as the distribution of trailing zeros is not uniform,
- * e.g. the number of possible inputs with no trailing zeros is equal to
- * the number with 1 or more; the number with exactly 1 is equal to the
- * number with 2 or more, etc. Checking the last two bits covers 75% of
- * all numbers. Checking the last three covers 87.5%
- */
- while (!(n & 1)) {
- n >>= 1;
- cnt++;
- }
- return cnt;
-}
-
-/*
- * Shift a block of 16 bytes left by shift bits
- */
-static void ocb_block_lshift(const unsigned char *in, size_t shift,
- unsigned char *out)
-{
- unsigned char shift_mask;
- int i;
- unsigned char mask[15];
-
- shift_mask = 0xff;
- shift_mask <<= (8 - shift);
- for (i = 15; i >= 0; i--) {
- if (i > 0) {
- mask[i - 1] = in[i] & shift_mask;
- mask[i - 1] >>= 8 - shift;
- }
- out[i] = in[i] << shift;
-
- if (i != 15) {
- out[i] ^= mask[i];
- }
- }
-}
-
-/*
- * Perform a "double" operation as per OCB spec
- */
-static void ocb_double(OCB_BLOCK *in, OCB_BLOCK *out)
-{
- unsigned char mask;
-
- /*
- * Calculate the mask based on the most significant bit. There are more
- * efficient ways to do this - but this way is constant time
- */
- mask = in->c[0] & 0x80;
- mask >>= 7;
- mask *= 135;
-
- ocb_block_lshift(in->c, 1, out->c);
-
- out->c[15] ^= mask;
-}
-
-/*
- * Perform an xor on in1 and in2 - each of len bytes. Store result in out
- */
-static void ocb_block_xor(const unsigned char *in1,
- const unsigned char *in2, size_t len,
- unsigned char *out)
-{
- size_t i;
- for (i = 0; i < len; i++) {
- out[i] = in1[i] ^ in2[i];
- }
-}
-
-/*
- * Lookup L_index in our lookup table. If we haven't already got it we need to
- * calculate it
- */
-static OCB_BLOCK *ocb_lookup_l(OCB128_CONTEXT *ctx, size_t idx)
-{
- size_t l_index = ctx->l_index;
-
- if (idx <= l_index) {
- return ctx->l + idx;
- }
-
- /* We don't have it - so calculate it */
- if (idx >= ctx->max_l_index) {
- void *tmp_ptr;
- /*
- * Each additional entry allows to process almost double as
- * much data, so that in linear world the table will need to
- * be expanded with smaller and smaller increments. Originally
- * it was doubling in size, which was a waste. Growing it
- * linearly is not formally optimal, but is simpler to implement.
- * We grow table by minimally required 4*n that would accommodate
- * the index.
- */
- ctx->max_l_index += (idx - ctx->max_l_index + 4) & ~3;
- tmp_ptr =
- OPENSSL_realloc(ctx->l, ctx->max_l_index * sizeof(OCB_BLOCK));
- if (tmp_ptr == NULL) /* prevent ctx->l from being clobbered */
- return NULL;
- ctx->l = tmp_ptr;
- }
- while (l_index < idx) {
- ocb_double(ctx->l + l_index, ctx->l + l_index + 1);
- l_index++;
- }
- ctx->l_index = l_index;
-
- return ctx->l + idx;
-}
-
-/*
- * Create a new OCB128_CONTEXT
- */
-OCB128_CONTEXT *CRYPTO_ocb128_new(void *keyenc, void *keydec,
- block128_f encrypt, block128_f decrypt,
- ocb128_f stream)
-{
- OCB128_CONTEXT *octx;
- int ret;
-
- if ((octx = OPENSSL_malloc(sizeof(*octx))) != NULL) {
- ret = CRYPTO_ocb128_init(octx, keyenc, keydec, encrypt, decrypt,
- stream);
- if (ret)
- return octx;
- OPENSSL_free(octx);
- }
-
- return NULL;
-}
-
-/*
- * Initialise an existing OCB128_CONTEXT
- */
-int CRYPTO_ocb128_init(OCB128_CONTEXT *ctx, void *keyenc, void *keydec,
- block128_f encrypt, block128_f decrypt,
- ocb128_f stream)
-{
- memset(ctx, 0, sizeof(*ctx));
- ctx->l_index = 0;
- ctx->max_l_index = 5;
- ctx->l = OPENSSL_malloc(ctx->max_l_index * 16);
- if (ctx->l == NULL)
- return 0;
-
- /*
- * We set both the encryption and decryption key schedules - decryption
- * needs both. Don't really need decryption schedule if only doing
- * encryption - but it simplifies things to take it anyway
- */
- ctx->encrypt = encrypt;
- ctx->decrypt = decrypt;
- ctx->stream = stream;
- ctx->keyenc = keyenc;
- ctx->keydec = keydec;
-
- /* L_* = ENCIPHER(K, zeros(128)) */
- ctx->encrypt(ctx->l_star.c, ctx->l_star.c, ctx->keyenc);
-
- /* L_$ = double(L_*) */
- ocb_double(&ctx->l_star, &ctx->l_dollar);
-
- /* L_0 = double(L_$) */
- ocb_double(&ctx->l_dollar, ctx->l);
-
- /* L_{i} = double(L_{i-1}) */
- ocb_double(ctx->l, ctx->l+1);
- ocb_double(ctx->l+1, ctx->l+2);
- ocb_double(ctx->l+2, ctx->l+3);
- ocb_double(ctx->l+3, ctx->l+4);
- ctx->l_index = 4; /* enough to process up to 496 bytes */
-
- return 1;
-}
-
-/*
- * Copy an OCB128_CONTEXT object
- */
-int CRYPTO_ocb128_copy_ctx(OCB128_CONTEXT *dest, OCB128_CONTEXT *src,
- void *keyenc, void *keydec)
-{
- memcpy(dest, src, sizeof(OCB128_CONTEXT));
- if (keyenc)
- dest->keyenc = keyenc;
- if (keydec)
- dest->keydec = keydec;
- if (src->l) {
- dest->l = OPENSSL_malloc(src->max_l_index * 16);
- if (dest->l == NULL)
- return 0;
- memcpy(dest->l, src->l, (src->l_index + 1) * 16);
- }
- return 1;
-}
-
-/*
- * Set the IV to be used for this operation. Must be 1 - 15 bytes.
- */
-int CRYPTO_ocb128_setiv(OCB128_CONTEXT *ctx, const unsigned char *iv,
- size_t len, size_t taglen)
-{
- unsigned char ktop[16], tmp[16], mask;
- unsigned char stretch[24], nonce[16];
- size_t bottom, shift;
-
- /*
- * Spec says IV is 120 bits or fewer - it allows non byte aligned lengths.
- * We don't support this at this stage
- */
- if ((len > 15) || (len < 1) || (taglen > 16) || (taglen < 1)) {
- return -1;
- }
-
- /* Nonce = num2str(TAGLEN mod 128,7) || zeros(120-bitlen(N)) || 1 || N */
- nonce[0] = ((taglen * 8) % 128) << 1;
- memset(nonce + 1, 0, 15);
- memcpy(nonce + 16 - len, iv, len);
- nonce[15 - len] |= 1;
-
- /* Ktop = ENCIPHER(K, Nonce[1..122] || zeros(6)) */
- memcpy(tmp, nonce, 16);
- tmp[15] &= 0xc0;
- ctx->encrypt(tmp, ktop, ctx->keyenc);
-
- /* Stretch = Ktop || (Ktop[1..64] xor Ktop[9..72]) */
- memcpy(stretch, ktop, 16);
- ocb_block_xor(ktop, ktop + 1, 8, stretch + 16);
-
- /* bottom = str2num(Nonce[123..128]) */
- bottom = nonce[15] & 0x3f;
-
- /* Offset_0 = Stretch[1+bottom..128+bottom] */
- shift = bottom % 8;
- ocb_block_lshift(stretch + (bottom / 8), shift, ctx->offset.c);
- mask = 0xff;
- mask <<= 8 - shift;
- ctx->offset.c[15] |=
- (*(stretch + (bottom / 8) + 16) & mask) >> (8 - shift);
-
- return 1;
-}
-
-/*
- * Provide any AAD. This can be called multiple times. Only the final time can
- * have a partial block
- */
-int CRYPTO_ocb128_aad(OCB128_CONTEXT *ctx, const unsigned char *aad,
- size_t len)
-{
- u64 i, all_num_blocks;
- size_t num_blocks, last_len;
- OCB_BLOCK tmp1;
- OCB_BLOCK tmp2;
-
- /* Calculate the number of blocks of AAD provided now, and so far */
- num_blocks = len / 16;
- all_num_blocks = num_blocks + ctx->blocks_hashed;
-
- /* Loop through all full blocks of AAD */
- for (i = ctx->blocks_hashed + 1; i <= all_num_blocks; i++) {
- OCB_BLOCK *lookup;
- OCB_BLOCK *aad_block;
-
- /* Offset_i = Offset_{i-1} xor L_{ntz(i)} */
- lookup = ocb_lookup_l(ctx, ocb_ntz(i));
- if (lookup == NULL)
- return 0;
- ocb_block16_xor(&ctx->offset_aad, lookup, &ctx->offset_aad);
-
- /* Sum_i = Sum_{i-1} xor ENCIPHER(K, A_i xor Offset_i) */
- aad_block = (OCB_BLOCK *)(aad + ((i - ctx->blocks_hashed - 1) * 16));
- ocb_block16_xor(&ctx->offset_aad, aad_block, &tmp1);
- ctx->encrypt(tmp1.c, tmp2.c, ctx->keyenc);
- ocb_block16_xor(&ctx->sum, &tmp2, &ctx->sum);
- }
-
- /*
- * Check if we have any partial blocks left over. This is only valid in the
- * last call to this function
- */
- last_len = len % 16;
-
- if (last_len > 0) {
- /* Offset_* = Offset_m xor L_* */
- ocb_block16_xor(&ctx->offset_aad, &ctx->l_star, &ctx->offset_aad);
-
- /* CipherInput = (A_* || 1 || zeros(127-bitlen(A_*))) xor Offset_* */
- memset(&tmp1, 0, 16);
- memcpy(&tmp1, aad + (num_blocks * 16), last_len);
- ((unsigned char *)&tmp1)[last_len] = 0x80;
- ocb_block16_xor(&ctx->offset_aad, &tmp1, &tmp2);
-
- /* Sum = Sum_m xor ENCIPHER(K, CipherInput) */
- ctx->encrypt(tmp2.c, tmp1.c, ctx->keyenc);
- ocb_block16_xor(&ctx->sum, &tmp1, &ctx->sum);
- }
-
- ctx->blocks_hashed = all_num_blocks;
-
- return 1;
-}
-
-/*
- * Provide any data to be encrypted. This can be called multiple times. Only
- * the final time can have a partial block
- */
-int CRYPTO_ocb128_encrypt(OCB128_CONTEXT *ctx,
- const unsigned char *in, unsigned char *out,
- size_t len)
-{
- u64 i, all_num_blocks;
- size_t num_blocks, last_len;
- OCB_BLOCK tmp1;
- OCB_BLOCK tmp2;
- OCB_BLOCK pad;
-
- /*
- * Calculate the number of blocks of data to be encrypted provided now, and
- * so far
- */
- num_blocks = len / 16;
- all_num_blocks = num_blocks + ctx->blocks_processed;
-
- if (num_blocks && all_num_blocks == (size_t)all_num_blocks
- && ctx->stream != NULL) {
- size_t max_idx = 0, top = (size_t)all_num_blocks;
-
- /*
- * See how many L_{i} entries we need to process data at hand
- * and pre-compute missing entries in the table [if any]...
- */
- while (top >>= 1)
- max_idx++;
- if (ocb_lookup_l(ctx, max_idx) == NULL)
- return 0;
-
- ctx->stream(in, out, num_blocks, ctx->keyenc,
- (size_t)ctx->blocks_processed + 1, ctx->offset.c,
- (const unsigned char (*)[16])ctx->l, ctx->checksum.c);
- } else {
- /* Loop through all full blocks to be encrypted */
- for (i = ctx->blocks_processed + 1; i <= all_num_blocks; i++) {
- OCB_BLOCK *lookup;
- OCB_BLOCK *inblock;
- OCB_BLOCK *outblock;
-
- /* Offset_i = Offset_{i-1} xor L_{ntz(i)} */
- lookup = ocb_lookup_l(ctx, ocb_ntz(i));
- if (lookup == NULL)
- return 0;
- ocb_block16_xor(&ctx->offset, lookup, &ctx->offset);
-
- /* C_i = Offset_i xor ENCIPHER(K, P_i xor Offset_i) */
- inblock =
- (OCB_BLOCK *)(in + ((i - ctx->blocks_processed - 1) * 16));
- ocb_block16_xor_misaligned(&ctx->offset, inblock, &tmp1);
- /* Checksum_i = Checksum_{i-1} xor P_i */
- ocb_block16_xor_misaligned(&ctx->checksum, inblock, &ctx->checksum);
- ctx->encrypt(tmp1.c, tmp2.c, ctx->keyenc);
- outblock =
- (OCB_BLOCK *)(out + ((i - ctx->blocks_processed - 1) * 16));
- ocb_block16_xor_misaligned(&ctx->offset, &tmp2, outblock);
- }
- }
-
- /*
- * Check if we have any partial blocks left over. This is only valid in the
- * last call to this function
- */
- last_len = len % 16;
-
- if (last_len > 0) {
- /* Offset_* = Offset_m xor L_* */
- ocb_block16_xor(&ctx->offset, &ctx->l_star, &ctx->offset);
-
- /* Pad = ENCIPHER(K, Offset_*) */
- ctx->encrypt(ctx->offset.c, pad.c, ctx->keyenc);
-
- /* C_* = P_* xor Pad[1..bitlen(P_*)] */
- ocb_block_xor(in + (len / 16) * 16, (unsigned char *)&pad, last_len,
- out + (num_blocks * 16));
-
- /* Checksum_* = Checksum_m xor (P_* || 1 || zeros(127-bitlen(P_*))) */
- memset(&tmp1, 0, 16);
- memcpy(&tmp1, in + (len / 16) * 16, last_len);
- ((unsigned char *)(&tmp1))[last_len] = 0x80;
- ocb_block16_xor(&ctx->checksum, &tmp1, &ctx->checksum);
- }
-
- ctx->blocks_processed = all_num_blocks;
-
- return 1;
-}
-
-/*
- * Provide any data to be decrypted. This can be called multiple times. Only
- * the final time can have a partial block
- */
-int CRYPTO_ocb128_decrypt(OCB128_CONTEXT *ctx,
- const unsigned char *in, unsigned char *out,
- size_t len)
-{
- u64 i, all_num_blocks;
- size_t num_blocks, last_len;
- OCB_BLOCK tmp1;
- OCB_BLOCK tmp2;
- OCB_BLOCK pad;
-
- /*
- * Calculate the number of blocks of data to be decrypted provided now, and
- * so far
- */
- num_blocks = len / 16;
- all_num_blocks = num_blocks + ctx->blocks_processed;
-
- if (num_blocks && all_num_blocks == (size_t)all_num_blocks
- && ctx->stream != NULL) {
- size_t max_idx = 0, top = (size_t)all_num_blocks;
-
- /*
- * See how many L_{i} entries we need to process data at hand
- * and pre-compute missing entries in the table [if any]...
- */
- while (top >>= 1)
- max_idx++;
- if (ocb_lookup_l(ctx, max_idx) == NULL)
- return 0;
-
- ctx->stream(in, out, num_blocks, ctx->keydec,
- (size_t)ctx->blocks_processed + 1, ctx->offset.c,
- (const unsigned char (*)[16])ctx->l, ctx->checksum.c);
- } else {
- /* Loop through all full blocks to be decrypted */
- for (i = ctx->blocks_processed + 1; i <= all_num_blocks; i++) {
- OCB_BLOCK *inblock;
- OCB_BLOCK *outblock;
-
- /* Offset_i = Offset_{i-1} xor L_{ntz(i)} */
- OCB_BLOCK *lookup = ocb_lookup_l(ctx, ocb_ntz(i));
- if (lookup == NULL)
- return 0;
- ocb_block16_xor(&ctx->offset, lookup, &ctx->offset);
-
- /* P_i = Offset_i xor DECIPHER(K, C_i xor Offset_i) */
- inblock =
- (OCB_BLOCK *)(in + ((i - ctx->blocks_processed - 1) * 16));
- ocb_block16_xor_misaligned(&ctx->offset, inblock, &tmp1);
- ctx->decrypt(tmp1.c, tmp2.c, ctx->keydec);
- outblock =
- (OCB_BLOCK *)(out + ((i - ctx->blocks_processed - 1) * 16));
- ocb_block16_xor_misaligned(&ctx->offset, &tmp2, outblock);
-
- /* Checksum_i = Checksum_{i-1} xor P_i */
- ocb_block16_xor_misaligned(&ctx->checksum, outblock, &ctx->checksum);
- }
- }
-
- /*
- * Check if we have any partial blocks left over. This is only valid in the
- * last call to this function
- */
- last_len = len % 16;
-
- if (last_len > 0) {
- /* Offset_* = Offset_m xor L_* */
- ocb_block16_xor(&ctx->offset, &ctx->l_star, &ctx->offset);
-
- /* Pad = ENCIPHER(K, Offset_*) */
- ctx->encrypt(ctx->offset.c, pad.c, ctx->keyenc);
-
- /* P_* = C_* xor Pad[1..bitlen(C_*)] */
- ocb_block_xor(in + (len / 16) * 16, (unsigned char *)&pad, last_len,
- out + (num_blocks * 16));
-
- /* Checksum_* = Checksum_m xor (P_* || 1 || zeros(127-bitlen(P_*))) */
- memset(&tmp1, 0, 16);
- memcpy(&tmp1, out + (len / 16) * 16, last_len);
- ((unsigned char *)(&tmp1))[last_len] = 0x80;
- ocb_block16_xor(&ctx->checksum, &tmp1, &ctx->checksum);
- }
-
- ctx->blocks_processed = all_num_blocks;
-
- return 1;
-}
-
-/*
- * Calculate the tag and verify it against the supplied tag
- */
-int CRYPTO_ocb128_finish(OCB128_CONTEXT *ctx, const unsigned char *tag,
- size_t len)
-{
- OCB_BLOCK tmp1, tmp2;
-
- /*
- * Tag = ENCIPHER(K, Checksum_* xor Offset_* xor L_$) xor HASH(K,A)
- */
- ocb_block16_xor(&ctx->checksum, &ctx->offset, &tmp1);
- ocb_block16_xor(&tmp1, &ctx->l_dollar, &tmp2);
- ctx->encrypt(tmp2.c, tmp1.c, ctx->keyenc);
- ocb_block16_xor(&tmp1, &ctx->sum, &ctx->tag);
-
- if (len > 16 || len < 1) {
- return -1;
- }
-
- /* Compare the tag if we've been given one */
- if (tag)
- return CRYPTO_memcmp(&ctx->tag, tag, len);
- else
- return -1;
-}
-
-/*
- * Retrieve the calculated tag
- */
-int CRYPTO_ocb128_tag(OCB128_CONTEXT *ctx, unsigned char *tag, size_t len)
-{
- if (len > 16 || len < 1) {
- return -1;
- }
-
- /* Calculate the tag */
- CRYPTO_ocb128_finish(ctx, NULL, 0);
-
- /* Copy the tag into the supplied buffer */
- memcpy(tag, &ctx->tag, len);
-
- return 1;
-}
-
-/*
- * Release all resources
- */
-void CRYPTO_ocb128_cleanup(OCB128_CONTEXT *ctx)
-{
- if (ctx) {
- OPENSSL_clear_free(ctx->l, ctx->max_l_index * 16);
- OPENSSL_cleanse(ctx, sizeof(*ctx));
- }
-}
-
-#endif /* OPENSSL_NO_OCB */
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