diff options
Diffstat (limited to 'crypto/heimdal/lib/krb5/crypto-evp.c')
| -rw-r--r-- | crypto/heimdal/lib/krb5/crypto-evp.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/crypto/heimdal/lib/krb5/crypto-evp.c b/crypto/heimdal/lib/krb5/crypto-evp.c new file mode 100644 index 000000000000..e8fb1caf6ae8 --- /dev/null +++ b/crypto/heimdal/lib/krb5/crypto-evp.c @@ -0,0 +1,182 @@ +/* + * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include "krb5_locl.h" + +void +_krb5_evp_schedule(krb5_context context, + struct _krb5_key_type *kt, + struct _krb5_key_data *kd) +{ + struct _krb5_evp_schedule *key = kd->schedule->data; + const EVP_CIPHER *c = (*kt->evp)(); + + EVP_CIPHER_CTX_init(&key->ectx); + EVP_CIPHER_CTX_init(&key->dctx); + + EVP_CipherInit_ex(&key->ectx, c, NULL, kd->key->keyvalue.data, NULL, 1); + EVP_CipherInit_ex(&key->dctx, c, NULL, kd->key->keyvalue.data, NULL, 0); +} + +void +_krb5_evp_cleanup(krb5_context context, struct _krb5_key_data *kd) +{ + struct _krb5_evp_schedule *key = kd->schedule->data; + EVP_CIPHER_CTX_cleanup(&key->ectx); + EVP_CIPHER_CTX_cleanup(&key->dctx); +} + +krb5_error_code +_krb5_evp_encrypt(krb5_context context, + struct _krb5_key_data *key, + void *data, + size_t len, + krb5_boolean encryptp, + int usage, + void *ivec) +{ + struct _krb5_evp_schedule *ctx = key->schedule->data; + EVP_CIPHER_CTX *c; + c = encryptp ? &ctx->ectx : &ctx->dctx; + if (ivec == NULL) { + /* alloca ? */ + size_t len2 = EVP_CIPHER_CTX_iv_length(c); + void *loiv = malloc(len2); + if (loiv == NULL) { + krb5_clear_error_message(context); + return ENOMEM; + } + memset(loiv, 0, len2); + EVP_CipherInit_ex(c, NULL, NULL, NULL, loiv, -1); + free(loiv); + } else + EVP_CipherInit_ex(c, NULL, NULL, NULL, ivec, -1); + EVP_Cipher(c, data, data, len); + return 0; +} + +static const unsigned char zero_ivec[EVP_MAX_BLOCK_LENGTH] = { 0 }; + +krb5_error_code +_krb5_evp_encrypt_cts(krb5_context context, + struct _krb5_key_data *key, + void *data, + size_t len, + krb5_boolean encryptp, + int usage, + void *ivec) +{ + size_t i, blocksize; + struct _krb5_evp_schedule *ctx = key->schedule->data; + unsigned char tmp[EVP_MAX_BLOCK_LENGTH], ivec2[EVP_MAX_BLOCK_LENGTH]; + EVP_CIPHER_CTX *c; + unsigned char *p; + + c = encryptp ? &ctx->ectx : &ctx->dctx; + + blocksize = EVP_CIPHER_CTX_block_size(c); + + if (len < blocksize) { + krb5_set_error_message(context, EINVAL, + "message block too short"); + return EINVAL; + } else if (len == blocksize) { + EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1); + EVP_Cipher(c, data, data, len); + return 0; + } + + if (ivec) + EVP_CipherInit_ex(c, NULL, NULL, NULL, ivec, -1); + else + EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1); + + if (encryptp) { + + p = data; + i = ((len - 1) / blocksize) * blocksize; + EVP_Cipher(c, p, p, i); + p += i - blocksize; + len -= i; + memcpy(ivec2, p, blocksize); + + for (i = 0; i < len; i++) + tmp[i] = p[i + blocksize] ^ ivec2[i]; + for (; i < blocksize; i++) + tmp[i] = 0 ^ ivec2[i]; + + EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1); + EVP_Cipher(c, p, tmp, blocksize); + + memcpy(p + blocksize, ivec2, len); + if (ivec) + memcpy(ivec, p, blocksize); + } else { + unsigned char tmp2[EVP_MAX_BLOCK_LENGTH], tmp3[EVP_MAX_BLOCK_LENGTH]; + + p = data; + if (len > blocksize * 2) { + /* remove last two blocks and round up, decrypt this with cbc, then do cts dance */ + i = ((((len - blocksize * 2) + blocksize - 1) / blocksize) * blocksize); + memcpy(ivec2, p + i - blocksize, blocksize); + EVP_Cipher(c, p, p, i); + p += i; + len -= i + blocksize; + } else { + if (ivec) + memcpy(ivec2, ivec, blocksize); + else + memcpy(ivec2, zero_ivec, blocksize); + len -= blocksize; + } + + memcpy(tmp, p, blocksize); + EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1); + EVP_Cipher(c, tmp2, p, blocksize); + + memcpy(tmp3, p + blocksize, len); + memcpy(tmp3 + len, tmp2 + len, blocksize - len); /* xor 0 */ + + for (i = 0; i < len; i++) + p[i + blocksize] = tmp2[i] ^ tmp3[i]; + + EVP_CipherInit_ex(c, NULL, NULL, NULL, zero_ivec, -1); + EVP_Cipher(c, p, tmp3, blocksize); + + for (i = 0; i < blocksize; i++) + p[i] ^= ivec2[i]; + if (ivec) + memcpy(ivec, tmp, blocksize); + } + return 0; +} |