From b4062c4bb7a6835838f5212a75c8e98699517098 Mon Sep 17 00:00:00 2001 From: Tobias Brunner Date: Tue, 11 Sep 2018 11:05:21 +0200 Subject: [PATCH] botan: Add support for X25519 --- src/libstrongswan/plugins/botan/Makefile.am | 3 +- .../plugins/botan/botan_plugin.c | 6 + .../plugins/botan/botan_x25519.c | 176 ++++++++++++++++++ .../plugins/botan/botan_x25519.h | 42 +++++ 4 files changed, 226 insertions(+), 1 deletion(-) create mode 100644 src/libstrongswan/plugins/botan/botan_x25519.c create mode 100644 src/libstrongswan/plugins/botan/botan_x25519.h diff --git a/src/libstrongswan/plugins/botan/Makefile.am b/src/libstrongswan/plugins/botan/Makefile.am index 1188841d3..c1160145a 100644 --- a/src/libstrongswan/plugins/botan/Makefile.am +++ b/src/libstrongswan/plugins/botan/Makefile.am @@ -25,7 +25,8 @@ libstrongswan_botan_la_SOURCES = \ botan_ec_private_key.h botan_ec_private_key.c \ botan_util.h botan_util.c \ botan_util_keys.h botan_util_keys.c \ - botan_gcm.h botan_gcm.c + botan_gcm.h botan_gcm.c \ + botan_x25519.h botan_x25519.c libstrongswan_botan_la_LDFLAGS = -module -avoid-version libstrongswan_botan_la_LIBADD = $(botan_LIBS) diff --git a/src/libstrongswan/plugins/botan/botan_plugin.c b/src/libstrongswan/plugins/botan/botan_plugin.c index b387a2bd1..fd8e5f5a6 100644 --- a/src/libstrongswan/plugins/botan/botan_plugin.c +++ b/src/libstrongswan/plugins/botan/botan_plugin.c @@ -38,6 +38,7 @@ #include "botan_ec_private_key.h" #include "botan_gcm.h" #include "botan_util_keys.h" +#include "botan_x25519.h" #include @@ -94,6 +95,11 @@ METHOD(plugin_t, get_features, int, PLUGIN_PROVIDE(DH, ECP_384_BP), PLUGIN_PROVIDE(DH, ECP_512_BP), #endif +#ifdef BOTAN_HAS_X25519 + PLUGIN_REGISTER(DH, botan_x25519_create), + PLUGIN_PROVIDE(DH, CURVE_25519), +#endif + /* crypters */ PLUGIN_REGISTER(CRYPTER, botan_crypter_create), #ifdef BOTAN_HAS_AES diff --git a/src/libstrongswan/plugins/botan/botan_x25519.c b/src/libstrongswan/plugins/botan/botan_x25519.c new file mode 100644 index 000000000..519f29f55 --- /dev/null +++ b/src/libstrongswan/plugins/botan/botan_x25519.c @@ -0,0 +1,176 @@ +/* + * Copyright (C) 2018 Tobias Brunner + * HSR Hochschule fuer Technik Rapperswil + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include "botan_x25519.h" + +#include + +#ifdef BOTAN_HAS_X25519 + +#include "botan_util.h" + +#include + +#include + +typedef struct private_diffie_hellman_t private_diffie_hellman_t; + +/** + * Private data + */ +struct private_diffie_hellman_t { + + /** + * Public interface + */ + diffie_hellman_t public; + + /** + * Private key + */ + botan_privkey_t key; + + /** + * Shared secret + */ + chunk_t shared_secret; +}; + +METHOD(diffie_hellman_t, set_other_public_value, bool, + private_diffie_hellman_t *this, chunk_t value) +{ + if (!diffie_hellman_verify_value(CURVE_25519, value)) + { + return FALSE; + } + + chunk_clear(&this->shared_secret); + + return botan_dh_key_derivation(this->key, value, &this->shared_secret); +} + +METHOD(diffie_hellman_t, get_my_public_value, bool, + private_diffie_hellman_t *this, chunk_t *value) +{ + value->len = 0; + if (botan_pk_op_key_agreement_export_public(this->key, NULL, &value->len) + != BOTAN_FFI_ERROR_INSUFFICIENT_BUFFER_SPACE) + { + return FALSE; + } + + *value = chunk_alloc(value->len); + if (botan_pk_op_key_agreement_export_public(this->key, value->ptr, + &value->len)) + { + chunk_free(value); + return FALSE; + } + return TRUE; +} + +METHOD(diffie_hellman_t, set_private_value, bool, + private_diffie_hellman_t *this, chunk_t value) +{ + if (value.len != 32) + { + return FALSE; + } + + chunk_clear(&this->shared_secret); + + if (botan_privkey_destroy(this->key)) + { + return FALSE; + } + + if (botan_privkey_load_x25519(&this->key, value.ptr)) + { + return FALSE; + } + return TRUE; +} + +METHOD(diffie_hellman_t, get_shared_secret, bool, + private_diffie_hellman_t *this, chunk_t *secret) +{ + if (!this->shared_secret.len) + { + return FALSE; + } + *secret = chunk_clone(this->shared_secret); + return TRUE; +} + +METHOD(diffie_hellman_t, get_dh_group, diffie_hellman_group_t, + private_diffie_hellman_t *this) +{ + return CURVE_25519; +} + +METHOD(diffie_hellman_t, destroy, void, + private_diffie_hellman_t *this) +{ + botan_privkey_destroy(this->key); + chunk_clear(&this->shared_secret); + free(this); +} + +/* + * Described in header + */ +diffie_hellman_t *botan_x25519_create(diffie_hellman_group_t group) +{ + private_diffie_hellman_t *this; + botan_rng_t rng; + + INIT(this, + .public = { + .get_shared_secret = _get_shared_secret, + .set_other_public_value = _set_other_public_value, + .get_my_public_value = _get_my_public_value, + .set_private_value = _set_private_value, + .get_dh_group = _get_dh_group, + .destroy = _destroy, + }, + ); + + if (botan_rng_init(&rng, "user")) + { + free(this); + return NULL; + } + + if (botan_privkey_create_ecdh(&this->key, rng, "curve25519")) + { + DBG1(DBG_LIB, "x25519 private key generation failed"); + botan_rng_destroy(rng); + free(this); + return NULL; + } + + botan_rng_destroy(rng); + return &this->public; +} + +#endif diff --git a/src/libstrongswan/plugins/botan/botan_x25519.h b/src/libstrongswan/plugins/botan/botan_x25519.h new file mode 100644 index 000000000..e95d6cde4 --- /dev/null +++ b/src/libstrongswan/plugins/botan/botan_x25519.h @@ -0,0 +1,42 @@ +/* + * Copyright (C) 2018 Tobias Brunner + * HSR Hochschule fuer Technik Rapperswil + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +/** + * @defgroup botan_x25519 botan_x25519 + * @{ @ingroup botan_p + */ + +#ifndef BOTAN_X25519_H_ +#define BOTAN_X25519_H_ + +#include + +/** + * Creates a new X25519 implementation using Botan. + * + * @param group DH group, must be CURVE_25519 + * @return object, NULL if not supported + */ +diffie_hellman_t *botan_x25519_create(diffie_hellman_group_t group); + +#endif /** BOTAN_X25519_H_ @}*/