diff options
Diffstat (limited to 'openssl-1.1.0h/crypto/modes/wrap128.c')
| -rw-r--r-- | openssl-1.1.0h/crypto/modes/wrap128.c | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/openssl-1.1.0h/crypto/modes/wrap128.c b/openssl-1.1.0h/crypto/modes/wrap128.c new file mode 100644 index 0000000..46809a0 --- /dev/null +++ b/openssl-1.1.0h/crypto/modes/wrap128.c @@ -0,0 +1,329 @@ +/* + * Copyright 2013-2016 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 + */ + +/** Beware! + * + * Following wrapping modes were designed for AES but this implementation + * allows you to use them for any 128 bit block cipher. + */ + +#include "internal/cryptlib.h" +#include <openssl/modes.h> + +/** RFC 3394 section 2.2.3.1 Default Initial Value */ +static const unsigned char default_iv[] = { + 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, +}; + +/** RFC 5649 section 3 Alternative Initial Value 32-bit constant */ +static const unsigned char default_aiv[] = { + 0xA6, 0x59, 0x59, 0xA6 +}; + +/** Input size limit: lower than maximum of standards but far larger than + * anything that will be used in practice. + */ +#define CRYPTO128_WRAP_MAX (1UL << 31) + +/** Wrapping according to RFC 3394 section 2.2.1. + * + * @param[in] key Key value. + * @param[in] iv IV value. Length = 8 bytes. NULL = use default_iv. + * @param[in] in Plaintext as n 64-bit blocks, n >= 2. + * @param[in] inlen Length of in. + * @param[out] out Ciphertext. Minimal buffer length = (inlen + 8) bytes. + * Input and output buffers can overlap if block function + * supports that. + * @param[in] block Block processing function. + * @return 0 if inlen does not consist of n 64-bit blocks, n >= 2. + * or if inlen > CRYPTO128_WRAP_MAX. + * Output length if wrapping succeeded. + */ +size_t CRYPTO_128_wrap(void *key, const unsigned char *iv, + unsigned char *out, + const unsigned char *in, size_t inlen, + block128_f block) +{ + unsigned char *A, B[16], *R; + size_t i, j, t; + if ((inlen & 0x7) || (inlen < 16) || (inlen > CRYPTO128_WRAP_MAX)) + return 0; + A = B; + t = 1; + memmove(out + 8, in, inlen); + if (!iv) + iv = default_iv; + + memcpy(A, iv, 8); + + for (j = 0; j < 6; j++) { + R = out + 8; + for (i = 0; i < inlen; i += 8, t++, R += 8) { + memcpy(B + 8, R, 8); + block(B, B, key); + A[7] ^= (unsigned char)(t & 0xff); + if (t > 0xff) { + A[6] ^= (unsigned char)((t >> 8) & 0xff); + A[5] ^= (unsigned char)((t >> 16) & 0xff); + A[4] ^= (unsigned char)((t >> 24) & 0xff); + } + memcpy(R, B + 8, 8); + } + } + memcpy(out, A, 8); + return inlen + 8; +} + +/** Unwrapping according to RFC 3394 section 2.2.2 steps 1-2. + * The IV check (step 3) is responsibility of the caller. + * + * @param[in] key Key value. + * @param[out] iv Unchecked IV value. Minimal buffer length = 8 bytes. + * @param[out] out Plaintext without IV. + * Minimal buffer length = (inlen - 8) bytes. + * Input and output buffers can overlap if block function + * supports that. + * @param[in] in Ciphertext as n 64-bit blocks. + * @param[in] inlen Length of in. + * @param[in] block Block processing function. + * @return 0 if inlen is out of range [24, CRYPTO128_WRAP_MAX] + * or if inlen is not a multiple of 8. + * Output length otherwise. + */ +static size_t crypto_128_unwrap_raw(void *key, unsigned char *iv, + unsigned char *out, + const unsigned char *in, size_t inlen, + block128_f block) +{ + unsigned char *A, B[16], *R; + size_t i, j, t; + inlen -= 8; + if ((inlen & 0x7) || (inlen < 16) || (inlen > CRYPTO128_WRAP_MAX)) + return 0; + A = B; + t = 6 * (inlen >> 3); + memcpy(A, in, 8); + memmove(out, in + 8, inlen); + for (j = 0; j < 6; j++) { + R = out + inlen - 8; + for (i = 0; i < inlen; i += 8, t--, R -= 8) { + A[7] ^= (unsigned char)(t & 0xff); + if (t > 0xff) { + A[6] ^= (unsigned char)((t >> 8) & 0xff); + A[5] ^= (unsigned char)((t >> 16) & 0xff); + A[4] ^= (unsigned char)((t >> 24) & 0xff); + } + memcpy(B + 8, R, 8); + block(B, B, key); + memcpy(R, B + 8, 8); + } + } + memcpy(iv, A, 8); + return inlen; +} + +/** Unwrapping according to RFC 3394 section 2.2.2, including the IV check. + * The first block of plaintext has to match the supplied IV, otherwise an + * error is returned. + * + * @param[in] key Key value. + * @param[out] iv IV value to match against. Length = 8 bytes. + * NULL = use default_iv. + * @param[out] out Plaintext without IV. + * Minimal buffer length = (inlen - 8) bytes. + * Input and output buffers can overlap if block function + * supports that. + * @param[in] in Ciphertext as n 64-bit blocks. + * @param[in] inlen Length of in. + * @param[in] block Block processing function. + * @return 0 if inlen is out of range [24, CRYPTO128_WRAP_MAX] + * or if inlen is not a multiple of 8 + * or if IV doesn't match expected value. + * Output length otherwise. + */ +size_t CRYPTO_128_unwrap(void *key, const unsigned char *iv, + unsigned char *out, const unsigned char *in, + size_t inlen, block128_f block) +{ + size_t ret; + unsigned char got_iv[8]; + + ret = crypto_128_unwrap_raw(key, got_iv, out, in, inlen, block); + if (ret == 0) + return 0; + + if (!iv) + iv = default_iv; + if (CRYPTO_memcmp(got_iv, iv, 8)) { + OPENSSL_cleanse(out, ret); + return 0; + } + return ret; +} + +/** Wrapping according to RFC 5649 section 4.1. + * + * @param[in] key Key value. + * @param[in] icv (Non-standard) IV, 4 bytes. NULL = use default_aiv. + * @param[out] out Ciphertext. Minimal buffer length = (inlen + 15) bytes. + * Input and output buffers can overlap if block function + * supports that. + * @param[in] in Plaintext as n 64-bit blocks, n >= 2. + * @param[in] inlen Length of in. + * @param[in] block Block processing function. + * @return 0 if inlen is out of range [1, CRYPTO128_WRAP_MAX]. + * Output length if wrapping succeeded. + */ +size_t CRYPTO_128_wrap_pad(void *key, const unsigned char *icv, + unsigned char *out, + const unsigned char *in, size_t inlen, + block128_f block) +{ + /* n: number of 64-bit blocks in the padded key data + * + * If length of plain text is not a multiple of 8, pad the plain text octet + * string on the right with octets of zeros, where final length is the + * smallest multiple of 8 that is greater than length of plain text. + * If length of plain text is a multiple of 8, then there is no padding. */ + const size_t blocks_padded = (inlen + 7) / 8; /* CEILING(m/8) */ + const size_t padded_len = blocks_padded * 8; + const size_t padding_len = padded_len - inlen; + /* RFC 5649 section 3: Alternative Initial Value */ + unsigned char aiv[8]; + int ret; + + /* Section 1: use 32-bit fixed field for plaintext octet length */ + if (inlen == 0 || inlen >= CRYPTO128_WRAP_MAX) + return 0; + + /* Section 3: Alternative Initial Value */ + if (!icv) + memcpy(aiv, default_aiv, 4); + else + memcpy(aiv, icv, 4); /* Standard doesn't mention this. */ + + aiv[4] = (inlen >> 24) & 0xFF; + aiv[5] = (inlen >> 16) & 0xFF; + aiv[6] = (inlen >> 8) & 0xFF; + aiv[7] = inlen & 0xFF; + + if (padded_len == 8) { + /* + * Section 4.1 - special case in step 2: If the padded plaintext + * contains exactly eight octets, then prepend the AIV and encrypt + * the resulting 128-bit block using AES in ECB mode. + */ + memmove(out + 8, in, inlen); + memcpy(out, aiv, 8); + memset(out + 8 + inlen, 0, padding_len); + block(out, out, key); + ret = 16; /* AIV + padded input */ + } else { + memmove(out, in, inlen); + memset(out + inlen, 0, padding_len); /* Section 4.1 step 1 */ + ret = CRYPTO_128_wrap(key, aiv, out, out, padded_len, block); + } + + return ret; +} + +/** Unwrapping according to RFC 5649 section 4.2. + * + * @param[in] key Key value. + * @param[in] icv (Non-standard) IV, 4 bytes. NULL = use default_aiv. + * @param[out] out Plaintext. Minimal buffer length = inlen bytes. + * Input and output buffers can overlap if block function + * supports that. + * @param[in] in Ciphertext as n 64-bit blocks. + * @param[in] inlen Length of in. + * @param[in] block Block processing function. + * @return 0 if inlen is out of range [16, CRYPTO128_WRAP_MAX], + * or if inlen is not a multiple of 8 + * or if IV and message length indicator doesn't match. + * Output length if unwrapping succeeded and IV matches. + */ +size_t CRYPTO_128_unwrap_pad(void *key, const unsigned char *icv, + unsigned char *out, + const unsigned char *in, size_t inlen, + block128_f block) +{ + /* n: number of 64-bit blocks in the padded key data */ + size_t n = inlen / 8 - 1; + size_t padded_len; + size_t padding_len; + size_t ptext_len; + /* RFC 5649 section 3: Alternative Initial Value */ + unsigned char aiv[8]; + static unsigned char zeros[8] = { 0x0 }; + size_t ret; + + /* Section 4.2: Ciphertext length has to be (n+1) 64-bit blocks. */ + if ((inlen & 0x7) != 0 || inlen < 16 || inlen >= CRYPTO128_WRAP_MAX) + return 0; + + memmove(out, in, inlen); + if (inlen == 16) { + /* + * Section 4.2 - special case in step 1: When n=1, the ciphertext + * contains exactly two 64-bit blocks and they are decrypted as a + * single AES block using AES in ECB mode: AIV | P[1] = DEC(K, C[0] | + * C[1]) + */ + block(out, out, key); + memcpy(aiv, out, 8); + /* Remove AIV */ + memmove(out, out + 8, 8); + padded_len = 8; + } else { + padded_len = inlen - 8; + ret = crypto_128_unwrap_raw(key, aiv, out, out, inlen, block); + if (padded_len != ret) { + OPENSSL_cleanse(out, inlen); + return 0; + } + } + + /* + * Section 3: AIV checks: Check that MSB(32,A) = A65959A6. Optionally a + * user-supplied value can be used (even if standard doesn't mention + * this). + */ + if ((!icv && CRYPTO_memcmp(aiv, default_aiv, 4)) + || (icv && CRYPTO_memcmp(aiv, icv, 4))) { + OPENSSL_cleanse(out, inlen); + return 0; + } + + /* + * Check that 8*(n-1) < LSB(32,AIV) <= 8*n. If so, let ptext_len = + * LSB(32,AIV). + */ + + ptext_len = ((unsigned int)aiv[4] << 24) + | ((unsigned int)aiv[5] << 16) + | ((unsigned int)aiv[6] << 8) + | (unsigned int)aiv[7]; + if (8 * (n - 1) >= ptext_len || ptext_len > 8 * n) { + OPENSSL_cleanse(out, inlen); + return 0; + } + + /* + * Check that the rightmost padding_len octets of the output data are + * zero. + */ + padding_len = padded_len - ptext_len; + if (CRYPTO_memcmp(out + ptext_len, zeros, padding_len) != 0) { + OPENSSL_cleanse(out, inlen); + return 0; + } + + /* Section 4.2 step 3: Remove padding */ + return ptext_len; +} |