RFC 5649 support.
Add support for RFC5649 key wrapping with padding. Add RFC5649 tests to evptests.txt Based on PR#3434 contribution by Petr Spacek <pspacek@redhat.com>. EVP support and minor changes added by Stephen Henson. Doxygen comment block updates by Tim Hudson. Reviewed-by: Tim Hudson <tjh@openssl.org>
This commit is contained in:
Dr. Stephen Henson
parent
58f4698f67
commit
d31fed73e2
6 changed files with 343 additions and 21 deletions
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@ -175,6 +175,7 @@ void OpenSSL_add_all_ciphers(void)
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EVP_add_cipher(EVP_aes_128_xts());
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EVP_add_cipher(EVP_aes_128_ccm());
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EVP_add_cipher(EVP_aes_128_wrap());
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EVP_add_cipher(EVP_aes_128_wrap_pad());
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EVP_add_cipher_alias(SN_aes_128_cbc,"AES128");
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EVP_add_cipher_alias(SN_aes_128_cbc,"aes128");
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EVP_add_cipher(EVP_aes_192_ecb());
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@ -187,6 +188,7 @@ void OpenSSL_add_all_ciphers(void)
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EVP_add_cipher(EVP_aes_192_gcm());
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EVP_add_cipher(EVP_aes_192_ccm());
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EVP_add_cipher(EVP_aes_192_wrap());
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EVP_add_cipher(EVP_aes_192_wrap_pad());
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EVP_add_cipher_alias(SN_aes_192_cbc,"AES192");
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EVP_add_cipher_alias(SN_aes_192_cbc,"aes192");
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EVP_add_cipher(EVP_aes_256_ecb());
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@ -200,6 +202,7 @@ void OpenSSL_add_all_ciphers(void)
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EVP_add_cipher(EVP_aes_256_xts());
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EVP_add_cipher(EVP_aes_256_ccm());
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EVP_add_cipher(EVP_aes_256_wrap());
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EVP_add_cipher(EVP_aes_256_wrap_pad());
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EVP_add_cipher_alias(SN_aes_256_cbc,"AES256");
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EVP_add_cipher_alias(SN_aes_256_cbc,"aes256");
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#if !defined(OPENSSL_NO_SHA) && !defined(OPENSSL_NO_SHA1)
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@ -1,5 +1,5 @@
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/* ====================================================================
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* Copyright (c) 2001-2011 The OpenSSL Project. All rights reserved.
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* Copyright (c) 2001-2014 The OpenSSL Project. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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@ -2086,7 +2086,7 @@ static int aes_wrap_init_key(EVP_CIPHER_CTX *ctx, const unsigned char *key,
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}
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if (iv)
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{
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memcpy(ctx->iv, iv, 8);
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memcpy(ctx->iv, iv, EVP_CIPHER_CTX_iv_length(ctx));
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wctx->iv = ctx->iv;
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}
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return 1;
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@ -2097,27 +2097,62 @@ static int aes_wrap_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
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{
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EVP_AES_WRAP_CTX *wctx = ctx->cipher_data;
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size_t rv;
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/* AES wrap with padding has IV length of 4, without padding 8 */
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int pad = EVP_CIPHER_CTX_iv_length(ctx) == 4;
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/* No final operation so always return zero length */
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if (!in)
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return 0;
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if (inlen % 8)
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/* Input length must always be non-zero */
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if (!inlen)
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return -1;
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if (ctx->encrypt && inlen < 8)
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/* If decrypting need at least 16 bytes and multiple of 8 */
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if (!ctx->encrypt && (inlen < 16 || inlen & 0x7))
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return -1;
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if (!ctx->encrypt && inlen < 16)
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/* If not padding input must be multiple of 8 */
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if (!pad && inlen & 0x7)
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return -1;
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if (!out)
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{
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if (ctx->encrypt)
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{
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/* If padding round up to multiple of 8 */
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if (pad)
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inlen = (inlen + 7)/8 * 8;
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/* 8 byte prefix */
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return inlen + 8;
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}
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else
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{
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/* If not padding output will be exactly 8 bytes
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* smaller than input. If padding it will be at
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* least 8 bytes smaller but we don't know how
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* much.
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*/
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return inlen - 8;
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}
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}
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if (ctx->encrypt)
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rv = CRYPTO_128_wrap(&wctx->ks.ks, wctx->iv, out, in, inlen,
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if (pad)
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{
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if (ctx->encrypt)
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rv = CRYPTO_128_wrap_pad(&wctx->ks.ks, wctx->iv,
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out, in, inlen,
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(block128_f)AES_encrypt);
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else
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rv = CRYPTO_128_unwrap(&wctx->ks.ks, wctx->iv, out, in, inlen,
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else
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rv = CRYPTO_128_unwrap_pad(&wctx->ks.ks, wctx->iv,
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out, in, inlen,
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(block128_f)AES_decrypt);
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}
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else
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{
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if (ctx->encrypt)
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rv = CRYPTO_128_wrap(&wctx->ks.ks, wctx->iv,
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out, in, inlen,
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(block128_f)AES_encrypt);
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else
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rv = CRYPTO_128_unwrap(&wctx->ks.ks, wctx->iv,
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out, in, inlen,
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(block128_f)AES_decrypt);
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}
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return rv ? (int)rv : -1;
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}
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@ -2129,7 +2164,7 @@ static const EVP_CIPHER aes_128_wrap = {
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NID_id_aes128_wrap,
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8, 16, 8, WRAP_FLAGS,
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aes_wrap_init_key, aes_wrap_cipher,
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NULL,
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NULL,
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sizeof(EVP_AES_WRAP_CTX),
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NULL,NULL,NULL,NULL };
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@ -2142,7 +2177,7 @@ static const EVP_CIPHER aes_192_wrap = {
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NID_id_aes192_wrap,
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8, 24, 8, WRAP_FLAGS,
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aes_wrap_init_key, aes_wrap_cipher,
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NULL,
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NULL,
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sizeof(EVP_AES_WRAP_CTX),
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NULL,NULL,NULL,NULL };
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@ -2155,7 +2190,7 @@ static const EVP_CIPHER aes_256_wrap = {
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NID_id_aes256_wrap,
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8, 32, 8, WRAP_FLAGS,
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aes_wrap_init_key, aes_wrap_cipher,
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NULL,
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NULL,
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sizeof(EVP_AES_WRAP_CTX),
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NULL,NULL,NULL,NULL };
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@ -2164,4 +2199,43 @@ const EVP_CIPHER *EVP_aes_256_wrap(void)
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return &aes_256_wrap;
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}
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static const EVP_CIPHER aes_128_wrap_pad = {
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NID_id_aes128_wrap_pad,
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8, 16, 4, WRAP_FLAGS,
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aes_wrap_init_key, aes_wrap_cipher,
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NULL,
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sizeof(EVP_AES_WRAP_CTX),
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NULL,NULL,NULL,NULL };
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const EVP_CIPHER *EVP_aes_128_wrap_pad(void)
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{
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return &aes_128_wrap_pad;
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}
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static const EVP_CIPHER aes_192_wrap_pad = {
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NID_id_aes192_wrap_pad,
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8, 24, 4, WRAP_FLAGS,
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aes_wrap_init_key, aes_wrap_cipher,
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NULL,
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sizeof(EVP_AES_WRAP_CTX),
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NULL,NULL,NULL,NULL };
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const EVP_CIPHER *EVP_aes_192_wrap_pad(void)
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{
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return &aes_192_wrap_pad;
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}
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static const EVP_CIPHER aes_256_wrap_pad = {
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NID_id_aes256_wrap_pad,
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8, 32, 4, WRAP_FLAGS,
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aes_wrap_init_key, aes_wrap_cipher,
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NULL,
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sizeof(EVP_AES_WRAP_CTX),
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NULL,NULL,NULL,NULL };
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const EVP_CIPHER *EVP_aes_256_wrap_pad(void)
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{
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return &aes_256_wrap_pad;
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}
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#endif
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@ -849,6 +849,7 @@ const EVP_CIPHER *EVP_aes_128_ccm(void);
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const EVP_CIPHER *EVP_aes_128_gcm(void);
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const EVP_CIPHER *EVP_aes_128_xts(void);
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const EVP_CIPHER *EVP_aes_128_wrap(void);
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const EVP_CIPHER *EVP_aes_128_wrap_pad(void);
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const EVP_CIPHER *EVP_aes_192_ecb(void);
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const EVP_CIPHER *EVP_aes_192_cbc(void);
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const EVP_CIPHER *EVP_aes_192_cfb1(void);
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@ -860,6 +861,7 @@ const EVP_CIPHER *EVP_aes_192_ctr(void);
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const EVP_CIPHER *EVP_aes_192_ccm(void);
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const EVP_CIPHER *EVP_aes_192_gcm(void);
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const EVP_CIPHER *EVP_aes_192_wrap(void);
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const EVP_CIPHER *EVP_aes_192_wrap_pad(void);
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const EVP_CIPHER *EVP_aes_256_ecb(void);
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const EVP_CIPHER *EVP_aes_256_cbc(void);
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const EVP_CIPHER *EVP_aes_256_cfb1(void);
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@ -872,6 +874,7 @@ const EVP_CIPHER *EVP_aes_256_ccm(void);
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const EVP_CIPHER *EVP_aes_256_gcm(void);
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const EVP_CIPHER *EVP_aes_256_xts(void);
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const EVP_CIPHER *EVP_aes_256_wrap(void);
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const EVP_CIPHER *EVP_aes_256_wrap_pad(void);
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# if !defined(OPENSSL_NO_SHA) && !defined(OPENSSL_NO_SHA1)
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const EVP_CIPHER *EVP_aes_128_cbc_hmac_sha1(void);
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const EVP_CIPHER *EVP_aes_256_cbc_hmac_sha1(void);
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@ -401,3 +401,7 @@ id-aes256-wrap:000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F:
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id-aes192-wrap:000102030405060708090A0B0C0D0E0F1011121314151617::00112233445566778899AABBCCDDEEFF0001020304050607:031D33264E15D33268F24EC260743EDCE1C6C7DDEE725A936BA814915C6762D2
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id-aes256-wrap:000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F::00112233445566778899AABBCCDDEEFF0001020304050607:A8F9BC1612C68B3FF6E6F4FBE30E71E4769C8B80A32CB8958CD5D17D6B254DA1
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id-aes256-wrap:000102030405060708090A0B0C0D0E0F101112131415161718191A1B1C1D1E1F::00112233445566778899AABBCCDDEEFF000102030405060708090A0B0C0D0E0F:28C9F404C4B810F4CBCCB35CFB87F8263F5786E2D80ED326CBC7F0E71A99F43BFB988B9B7A02DD21
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# AES wrap tests from RFC5649
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id-aes192-wrap-pad:5840df6e29b02af1ab493b705bf16ea1ae8338f4dcc176a8::c37b7e6492584340bed12207808941155068f738:138bdeaa9b8fa7fc61f97742e72248ee5ae6ae5360d1ae6a5f54f373fa543b6a
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id-aes192-wrap-pad:5840df6e29b02af1ab493b705bf16ea1ae8338f4dcc176a8::466f7250617369:afbeb0f07dfbf5419200f2ccb50bb24f
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@ -141,3 +141,9 @@ size_t CRYPTO_128_wrap(void *key, const unsigned char *iv,
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size_t CRYPTO_128_unwrap(void *key, const unsigned char *iv,
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unsigned char *out,
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const unsigned char *in, size_t inlen, block128_f block);
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size_t CRYPTO_128_wrap_pad(void *key, const unsigned char *icv,
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unsigned char *out,
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const unsigned char *in, size_t inlen, block128_f block);
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size_t CRYPTO_128_unwrap_pad(void *key, const unsigned char *icv,
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unsigned char *out,
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const unsigned char *in, size_t inlen, block128_f block);
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@ -1,6 +1,7 @@
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/* crypto/modes/wrap128.c */
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/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
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* project.
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* Mode with padding contributed by Petr Spacek (pspacek@redhat.com).
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*/
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/* ====================================================================
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* Copyright (c) 2013 The OpenSSL Project. All rights reserved.
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@ -51,28 +52,55 @@
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* ====================================================================
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*/
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/** Beware!
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*
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* Following wrapping modes were designed for AES but this implementation
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* allows you to use them for any 128 bit block cipher.
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*/
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#include "cryptlib.h"
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#include <openssl/modes.h>
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/** RFC 3394 section 2.2.3.1 Default Initial Value */
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static const unsigned char default_iv[] = {
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0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6,
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};
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/* Input size limit: lower than maximum of standards but far larger than
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* anything that will be used in practice.
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/** RFC 5649 section 3 Alternative Initial Value 32-bit constant */
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static const unsigned char default_aiv[] = {
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0xA6, 0x59, 0x59, 0xA6
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};
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/** Input size limit: lower than maximum of standards but far larger than
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* anything that will be used in practice.
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*/
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#define CRYPTO128_WRAP_MAX (1UL << 31)
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/** Wrapping according to RFC 3394 section 2.2.1.
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*
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* @param[in] key Key value.
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* @param[in] iv IV value. Length = 8 bytes. NULL = use default_iv.
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* @param[in] in Plain text as n 64-bit blocks, n >= 2.
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* @param[in] inlen Length of in.
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* @param[out] out Cipher text. Minimal buffer length = (inlen + 8) bytes.
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* Input and output buffers can overlap if block function
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* supports that.
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* @param[in] block Block processing function.
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* @return 0 if inlen does not consist of n 64-bit blocks, n >= 2.
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* or if inlen > CRYPTO128_WRAP_MAX.
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* Output length if wrapping succeeded.
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*/
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size_t CRYPTO_128_wrap(void *key, const unsigned char *iv,
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unsigned char *out,
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const unsigned char *in, size_t inlen, block128_f block)
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{
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unsigned char *A, B[16], *R;
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size_t i, j, t;
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if ((inlen & 0x7) || (inlen < 8) || (inlen > CRYPTO128_WRAP_MAX))
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if ((inlen & 0x7) || (inlen < 16) || (inlen > CRYPTO128_WRAP_MAX))
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return 0;
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A = B;
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t = 1;
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memcpy(out + 8, in, inlen);
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memmove(out + 8, in, inlen);
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if (!iv)
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iv = default_iv;
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@ -99,9 +127,26 @@ size_t CRYPTO_128_wrap(void *key, const unsigned char *iv,
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return inlen + 8;
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}
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size_t CRYPTO_128_unwrap(void *key, const unsigned char *iv,
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unsigned char *out,
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const unsigned char *in, size_t inlen, block128_f block)
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/** Unwrapping according to RFC 3394 section 2.2.2 steps 1-2.
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* IV check (step 3) is responsibility of the caller.
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*
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* @param[in] key Key value.
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* @param[out] iv Unchecked IV value. Minimal buffer length = 8 bytes.
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* @param[out] out Plain text without IV.
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* Minimal buffer length = (inlen - 8) bytes.
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* Input and output buffers can overlap if block function
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* supports that.
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* @param[in] in Ciphertext text as n 64-bit blocks
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* @param[in] inlen Length of in.
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* @param[in] block Block processing function.
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* @return 0 if inlen is out of range [24, CRYPTO128_WRAP_MAX]
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* or if inlen is not multiply of 8.
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* Output length otherwise.
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*/
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static size_t crypto_128_unwrap_raw(void *key, unsigned char *iv,
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unsigned char *out, const unsigned char *in,
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size_t inlen, block128_f block)
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{
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unsigned char *A, B[16], *R;
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size_t i, j, t;
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@ -111,7 +156,7 @@ size_t CRYPTO_128_unwrap(void *key, const unsigned char *iv,
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A = B;
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t = 6 * (inlen >> 3);
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memcpy(A, in, 8);
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memcpy(out, in + 8, inlen);
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memmove(out, in + 8, inlen);
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for (j = 0; j < 6; j++)
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{
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R = out + inlen - 8;
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@ -129,12 +174,199 @@ size_t CRYPTO_128_unwrap(void *key, const unsigned char *iv,
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memcpy(R, B + 8, 8);
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}
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}
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memcpy(iv, A, 8);
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return inlen;
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}
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/** Unwrapping according to RFC 3394 section 2.2.2 including IV check.
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* First block of plain text have to match supplied IV otherwise an error is
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* returned.
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*
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* @param[in] key Key value.
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* @param[out] iv Unchecked IV value. Minimal buffer length = 8 bytes.
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* @param[out] out Plain text without IV.
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* Minimal buffer length = (inlen - 8) bytes.
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* Input and output buffers can overlap if block function
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* supports that.
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* @param[in] in Ciphertext text as n 64-bit blocks
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* @param[in] inlen Length of in.
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* @param[in] block Block processing function.
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* @return 0 if inlen is out of range [24, CRYPTO128_WRAP_MAX]
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* or if inlen is not multiply of 8
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* or if IV doesn't match expected value.
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* Output length otherwise.
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*/
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size_t CRYPTO_128_unwrap(void *key, const unsigned char *iv,
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unsigned char *out, const unsigned char *in, size_t inlen,
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block128_f block)
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{
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size_t ret;
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unsigned char got_iv[8];
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ret = crypto_128_unwrap_raw(key, got_iv, out, in, inlen, block);
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if (ret != inlen)
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return ret;
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if (!iv)
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iv = default_iv;
|
||||
if (memcmp(A, iv, 8))
|
||||
if (CRYPTO_memcmp(out, iv, 8))
|
||||
{
|
||||
OPENSSL_cleanse(out, inlen);
|
||||
return 0;
|
||||
}
|
||||
return inlen;
|
||||
}
|
||||
|
||||
/** 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 Cipher text. Minimal buffer length = (inlen + 15) bytes.
|
||||
* Input and output buffers can overlap if block function
|
||||
* supports that.
|
||||
* @param[in] in Plain text 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 */
|
||||
const size_t blocks_padded = (inlen + 8) / 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 Plain text. Minimal buffer length = inlen bytes.
|
||||
* Input and output buffers can overlap if block function
|
||||
* supports that.
|
||||
* @param[in] in Ciphertext text 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 multiply 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: Cipher text 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 = (aiv[4] << 24) | (aiv[5] << 16) | (aiv[6] << 8) | 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;
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue