From aa4d426b4d3527d7e166df1a05058c9a4a0f6683 Mon Sep 17 00:00:00 2001 From: Wojtek Kosior Date: Fri, 30 Apr 2021 00:33:56 +0200 Subject: initial/final commit --- openssl-1.1.0h/crypto/modes/ocb128.c | 568 +++++++++++++++++++++++++++++++++++ 1 file changed, 568 insertions(+) create mode 100644 openssl-1.1.0h/crypto/modes/ocb128.c (limited to 'openssl-1.1.0h/crypto/modes/ocb128.c') diff --git a/openssl-1.1.0h/crypto/modes/ocb128.c b/openssl-1.1.0h/crypto/modes/ocb128.c new file mode 100644 index 0000000..db794d0 --- /dev/null +++ b/openssl-1.1.0h/crypto/modes/ocb128.c @@ -0,0 +1,568 @@ +/* + * 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 +#include +#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 tmp; + + /* 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; + + /* 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); + + memcpy(tmp.c, aad, 16); + aad += 16; + + /* Sum_i = Sum_{i-1} xor ENCIPHER(K, A_i xor Offset_i) */ + ocb_block16_xor(&ctx->offset_aad, &tmp, &tmp); + ctx->encrypt(tmp.c, tmp.c, ctx->keyenc); + ocb_block16_xor(&tmp, &ctx->sum, &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(tmp.c, 0, 16); + memcpy(tmp.c, aad, last_len); + tmp.c[last_len] = 0x80; + ocb_block16_xor(&ctx->offset_aad, &tmp, &tmp); + + /* Sum = Sum_m xor ENCIPHER(K, CipherInput) */ + ctx->encrypt(tmp.c, tmp.c, ctx->keyenc); + ocb_block16_xor(&tmp, &ctx->sum, &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; + + /* + * 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 tmp; + + /* 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); + + memcpy(tmp.c, in, 16); + in += 16; + + /* Checksum_i = Checksum_{i-1} xor P_i */ + ocb_block16_xor(&tmp, &ctx->checksum, &ctx->checksum); + + /* C_i = Offset_i xor ENCIPHER(K, P_i xor Offset_i) */ + ocb_block16_xor(&ctx->offset, &tmp, &tmp); + ctx->encrypt(tmp.c, tmp.c, ctx->keyenc); + ocb_block16_xor(&ctx->offset, &tmp, &tmp); + + memcpy(out, tmp.c, 16); + out += 16; + } + } + + /* + * 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) { + OCB_BLOCK pad; + + /* 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, pad.c, last_len, out); + + /* Checksum_* = Checksum_m xor (P_* || 1 || zeros(127-bitlen(P_*))) */ + memset(pad.c, 0, 16); /* borrow pad */ + memcpy(pad.c, in, last_len); + pad.c[last_len] = 0x80; + ocb_block16_xor(&pad, &ctx->checksum, &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; + + /* + * 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 { + OCB_BLOCK tmp; + + /* Loop through all full blocks to be decrypted */ + for (i = ctx->blocks_processed + 1; i <= all_num_blocks; i++) { + + /* 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); + + memcpy(tmp.c, in, 16); + in += 16; + + /* P_i = Offset_i xor DECIPHER(K, C_i xor Offset_i) */ + ocb_block16_xor(&ctx->offset, &tmp, &tmp); + ctx->decrypt(tmp.c, tmp.c, ctx->keydec); + ocb_block16_xor(&ctx->offset, &tmp, &tmp); + + /* Checksum_i = Checksum_{i-1} xor P_i */ + ocb_block16_xor(&tmp, &ctx->checksum, &ctx->checksum); + + memcpy(out, tmp.c, 16); + out += 16; + } + } + + /* + * 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) { + OCB_BLOCK pad; + + /* 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, pad.c, last_len, out); + + /* Checksum_* = Checksum_m xor (P_* || 1 || zeros(127-bitlen(P_*))) */ + memset(pad.c, 0, 16); /* borrow pad */ + memcpy(pad.c, out, last_len); + pad.c[last_len] = 0x80; + ocb_block16_xor(&pad, &ctx->checksum, &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 tmp; + + /* + * Tag = ENCIPHER(K, Checksum_* xor Offset_* xor L_$) xor HASH(K,A) + */ + ocb_block16_xor(&ctx->checksum, &ctx->offset, &tmp); + ocb_block16_xor(&ctx->l_dollar, &tmp, &tmp); + ctx->encrypt(tmp.c, tmp.c, ctx->keyenc); + ocb_block16_xor(&tmp, &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.c, 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 */ -- cgit v1.2.3