diff options
author | Rene Mayrhofer <rene@mayrhofer.eu.org> | 2008-07-09 21:02:41 +0000 |
---|---|---|
committer | Rene Mayrhofer <rene@mayrhofer.eu.org> | 2008-07-09 21:02:41 +0000 |
commit | db67c87db3c9089ea8d2e14f617bf3d9e2af261f (patch) | |
tree | 665c0caea83d34c11c1517c4c57137bb58cba6fb /src/libstrongswan/plugins/openssl/openssl_crypter.c | |
parent | 1c088a8b6237ec67f63c23f97a0f2dc4e99af869 (diff) | |
download | vyos-strongswan-db67c87db3c9089ea8d2e14f617bf3d9e2af261f.tar.gz vyos-strongswan-db67c87db3c9089ea8d2e14f617bf3d9e2af261f.zip |
[svn-upgrade] Integrating new upstream version, strongswan (4.2.4)
Diffstat (limited to 'src/libstrongswan/plugins/openssl/openssl_crypter.c')
-rw-r--r-- | src/libstrongswan/plugins/openssl/openssl_crypter.c | 258 |
1 files changed, 258 insertions, 0 deletions
diff --git a/src/libstrongswan/plugins/openssl/openssl_crypter.c b/src/libstrongswan/plugins/openssl/openssl_crypter.c new file mode 100644 index 000000000..e59c4d615 --- /dev/null +++ b/src/libstrongswan/plugins/openssl/openssl_crypter.c @@ -0,0 +1,258 @@ +/* + * Copyright (C) 2008 Tobias Brunner + * Hochschule fuer Technik Rapperswil + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * for more details. + * + * $Id: openssl_crypter.c 4020 2008-05-28 12:20:38Z andreas $ + */ + +#include "openssl_crypter.h" + +#include <openssl/evp.h> + +typedef struct private_openssl_crypter_t private_openssl_crypter_t; + +/** + * Private data of openssl_crypter_t + */ +struct private_openssl_crypter_t { + + /** + * Public part of this class. + */ + openssl_crypter_t public; + + /* + * the key + */ + chunk_t key; + + /* + * the cipher to use + */ + const EVP_CIPHER *cipher; +}; + +/** + * Mapping from the algorithms defined in IKEv2 to + * OpenSSL algorithm names and their key length + */ +typedef struct { + /** + * Identifier specified in IKEv2 + */ + int ikev2_id; + + /** + * Name of the algorithm, as used in OpenSSL + */ + char *name; + + /** + * Minimum valid key length in bytes + */ + size_t key_size_min; + + /** + * Maximum valid key length in bytes + */ + size_t key_size_max; +} openssl_algorithm_t; + +#define END_OF_LIST -1 + +/** + * Algorithms for encryption + */ +static openssl_algorithm_t encryption_algs[] = { +/* {ENCR_DES_IV64, "***", 0, 0}, */ + {ENCR_DES, "des", 8, 8}, /* 64 bits */ + {ENCR_3DES, "des3", 24, 24}, /* 192 bits */ + {ENCR_RC5, "rc5", 5, 255}, /* 40 to 2040 bits, RFC 2451 */ + {ENCR_IDEA, "idea", 16, 16}, /* 128 bits, RFC 2451 */ + {ENCR_CAST, "cast", 5, 16}, /* 40 to 128 bits, RFC 2451 */ + {ENCR_BLOWFISH, "blowfish", 5, 56}, /* 40 to 448 bits, RFC 2451 */ +/* {ENCR_3IDEA, "***", 0, 0}, */ +/* {ENCR_DES_IV32, "***", 0, 0}, */ +/* {ENCR_NULL, "***", 0, 0}, */ /* handled separately */ +/* {ENCR_AES_CBC, "***", 0, 0}, */ /* handled separately */ +/* {ENCR_AES_CTR, "***", 0, 0}, */ /* disabled in evp.h */ + {END_OF_LIST, NULL, 0, 0}, +}; + +/** + * Look up an OpenSSL algorithm name and validate its key size + */ +static char* lookup_algorithm(openssl_algorithm_t *openssl_algo, + u_int16_t ikev2_algo, size_t *key_size) +{ + while (openssl_algo->ikev2_id != END_OF_LIST) + { + if (ikev2_algo == openssl_algo->ikev2_id) + { + /* set the key size if it is not set */ + if (*key_size == 0 && + (openssl_algo->key_size_min == openssl_algo->key_size_max)) + { + *key_size = openssl_algo->key_size_min; + } + + /* validate key size */ + if (*key_size < openssl_algo->key_size_min || + *key_size > openssl_algo->key_size_max) + { + return NULL; + } + return openssl_algo->name; + } + openssl_algo++; + } + return NULL; +} + +static void crypt(private_openssl_crypter_t *this, chunk_t data, + chunk_t iv, chunk_t *dst, int enc) +{ + int len; + u_char *out; + + out = data.ptr; + if (dst) + { + *dst = chunk_alloc(data.len); + out = dst->ptr; + } + EVP_CIPHER_CTX ctx; + EVP_CIPHER_CTX_init(&ctx); + EVP_CipherInit_ex(&ctx, this->cipher, NULL, this->key.ptr, iv.ptr, enc); + EVP_CIPHER_CTX_set_padding(&ctx, 0); /* disable padding */ + EVP_CipherUpdate(&ctx, out, &len, data.ptr, data.len); + EVP_CipherFinal_ex(&ctx, out, &len); /* since padding is disabled this does nothing */ + EVP_CIPHER_CTX_cleanup(&ctx); +} + +/** + * Implementation of crypter_t.decrypt. + */ +static void decrypt(private_openssl_crypter_t *this, chunk_t data, + chunk_t iv, chunk_t *dst) +{ + crypt(this, data, iv, dst, 0); +} + + +/** + * Implementation of crypter_t.encrypt. + */ +static void encrypt (private_openssl_crypter_t *this, chunk_t data, + chunk_t iv, chunk_t *dst) +{ + crypt(this, data, iv, dst, 1); +} + +/** + * Implementation of crypter_t.get_block_size. + */ +static size_t get_block_size(private_openssl_crypter_t *this) +{ + return this->cipher->block_size; +} + +/** + * Implementation of crypter_t.get_key_size. + */ +static size_t get_key_size(private_openssl_crypter_t *this) +{ + return this->key.len; +} + +/** + * Implementation of crypter_t.set_key. + */ +static void set_key(private_openssl_crypter_t *this, chunk_t key) +{ + memcpy(this->key.ptr, key.ptr, min(key.len, this->key.len)); +} + +/** + * Implementation of crypter_t.destroy. + */ +static void destroy (private_openssl_crypter_t *this) +{ + free(this->key.ptr); + free(this); +} + +/* + * Described in header + */ +openssl_crypter_t *openssl_crypter_create(encryption_algorithm_t algo, + size_t key_size) +{ + private_openssl_crypter_t *this; + + this = malloc_thing(private_openssl_crypter_t); + + switch (algo) + { + case ENCR_NULL: + this->cipher = EVP_enc_null(); + break; + case ENCR_AES_CBC: + switch (key_size) + { + case 16: /* AES 128 */ + this->cipher = EVP_get_cipherbyname("aes128"); + break; + case 24: /* AES-192 */ + this->cipher = EVP_get_cipherbyname("aes192"); + break; + case 32: /* AES-256 */ + this->cipher = EVP_get_cipherbyname("aes256"); + break; + default: + free(this); + return NULL; + } + break; + default: + { + char* name = lookup_algorithm(encryption_algs, algo, &key_size); + if (!name) + { + /* algo unavailable or key_size invalid */ + free(this); + return NULL; + } + this->cipher = EVP_get_cipherbyname(name); + break; + } + } + + if (!this->cipher) + { + /* OpenSSL does not support the requested algo */ + free(this); + return NULL; + } + + this->key = chunk_alloc(key_size); + + this->public.crypter_interface.encrypt = (void (*) (crypter_t *, chunk_t,chunk_t, chunk_t *)) encrypt; + this->public.crypter_interface.decrypt = (void (*) (crypter_t *, chunk_t , chunk_t, chunk_t *)) decrypt; + this->public.crypter_interface.get_block_size = (size_t (*) (crypter_t *)) get_block_size; + this->public.crypter_interface.get_key_size = (size_t (*) (crypter_t *)) get_key_size; + this->public.crypter_interface.set_key = (void (*) (crypter_t *,chunk_t)) set_key; + this->public.crypter_interface.destroy = (void (*) (crypter_t *)) destroy; + + return &this->public; +} |