--- /dev/null
+/*
+ * Copyright (C) 2010 Martin Willi
+ * Copyright (C) 2010 revosec AG
+ *
+ * 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.
+ */
+
+#include "tls_prf.h"
+
+typedef struct private_tls_prf12_t private_tls_prf12_t;
+
+/**
+ * Private data of an tls_prf_t object.
+ */
+struct private_tls_prf12_t {
+
+ /**
+ * Public tls_prf_t interface.
+ */
+ tls_prf_t public;
+
+ /**
+ * Underlying primitive PRF
+ */
+ prf_t *prf;
+};
+
+METHOD(tls_prf_t, set_key12, void,
+ private_tls_prf12_t *this, chunk_t key)
+{
+ this->prf->set_key(this->prf, key);
+}
+
+/**
+ * The P_hash function as in TLS 1.0/1.2
+ */
+static void p_hash(prf_t *prf, char *label, chunk_t seed, size_t block_size,
+ size_t bytes, char *out)
+{
+ char buf[block_size], abuf[block_size];
+ chunk_t a;
+
+ /* seed = label + seed */
+ seed = chunk_cata("cc", chunk_create(label, strlen(label)), seed);
+ /* A(0) = seed */
+ a = seed;
+
+ while (TRUE)
+ {
+ /* A(i) = HMAC_hash(secret, A(i-1)) */
+ prf->get_bytes(prf, a, abuf);
+ a = chunk_from_thing(abuf);
+ /* HMAC_hash(secret, A(i) + seed) */
+ prf->get_bytes(prf, a, NULL);
+ prf->get_bytes(prf, seed, buf);
+
+ if (bytes <= block_size)
+ {
+ memcpy(out, buf, bytes);
+ break;
+ }
+ memcpy(out, buf, block_size);
+ out += block_size;
+ bytes -= block_size;
+ }
+}
+
+METHOD(tls_prf_t, get_bytes12, void,
+ private_tls_prf12_t *this, char *label, chunk_t seed,
+ size_t bytes, char *out)
+{
+ p_hash(this->prf, label, seed, this->prf->get_block_size(this->prf),
+ bytes, out);
+}
+
+METHOD(tls_prf_t, destroy12, void,
+ private_tls_prf12_t *this)
+{
+ this->prf->destroy(this->prf);
+ free(this);
+}
+
+/**
+ * See header
+ */
+tls_prf_t *tls_prf_create_12(pseudo_random_function_t prf)
+{
+ private_tls_prf12_t *this;
+
+ INIT(this,
+ .public = {
+ .set_key = _set_key12,
+ .get_bytes = _get_bytes12,
+ .destroy = _destroy12,
+ },
+ .prf = lib->crypto->create_prf(lib->crypto, prf),
+ );
+ if (!this->prf)
+ {
+ free(this);
+ return NULL;
+ }
+ return &this->public;
+}
+
+
+typedef struct private_tls_prf10_t private_tls_prf10_t;
+
+/**
+ * Private data of an tls_prf_t object.
+ */
+struct private_tls_prf10_t {
+
+ /**
+ * Public tls_prf_t interface.
+ */
+ tls_prf_t public;
+
+ /**
+ * Underlying MD5 PRF
+ */
+ prf_t *md5;
+
+ /**
+ * Underlying SHA1 PRF
+ */
+ prf_t *sha1;
+};
+
+METHOD(tls_prf_t, set_key10, void,
+ private_tls_prf10_t *this, chunk_t key)
+{
+ size_t len = key.len / 2 + key.len % 2;
+
+ this->md5->set_key(this->md5, chunk_create(key.ptr, len));
+ this->sha1->set_key(this->sha1, chunk_create(key.ptr + key.len - len, len));
+}
+
+METHOD(tls_prf_t, get_bytes10, void,
+ private_tls_prf10_t *this, char *label, chunk_t seed,
+ size_t bytes, char *out)
+{
+ char buf[bytes];
+
+ p_hash(this->md5, label, seed, this->md5->get_block_size(this->md5),
+ bytes, out);
+ p_hash(this->sha1, label, seed, this->sha1->get_block_size(this->sha1),
+ bytes, buf);
+ memxor(out, buf, bytes);
+}
+
+METHOD(tls_prf_t, destroy10, void,
+ private_tls_prf10_t *this)
+{
+ DESTROY_IF(this->md5);
+ DESTROY_IF(this->sha1);
+ free(this);
+}
+
+/**
+ * See header
+ */
+tls_prf_t *tls_prf_create_10(pseudo_random_function_t prf)
+{
+ private_tls_prf10_t *this;
+
+ INIT(this,
+ .public = {
+ .set_key = _set_key10,
+ .get_bytes = _get_bytes10,
+ .destroy = _destroy10,
+ },
+ .md5 = lib->crypto->create_prf(lib->crypto, PRF_HMAC_MD5),
+ .sha1 = lib->crypto->create_prf(lib->crypto, PRF_HMAC_SHA1),
+ );
+ if (!this->md5 || !this->sha1)
+ {
+ destroy10(this);
+ return NULL;
+ }
+ return &this->public;
+}
--- /dev/null
+/*
+ * Copyright (C) 2010 Martin Willi
+ * Copyright (C) 2010 revosec AG
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup tls_prf tls_prf
+ * @{ @ingroup tls
+ */
+
+#ifndef TLS_PRF_H_
+#define TLS_PRF_H_
+
+typedef struct tls_prf_t tls_prf_t;
+
+#include <crypto/prfs/prf.h>
+
+/**
+ * The PRF function specified on TLS, based on HMAC.
+ */
+struct tls_prf_t {
+
+ /**
+ * Set the key of the PRF function.
+ *
+ * @param key key to set
+ */
+ void (*set_key)(tls_prf_t *this, chunk_t key);
+
+ /**
+ * Generate a series of bytes using a label and a seed.
+ *
+ * @param label ASCII input label
+ * @param seed seed input value
+ * @param bytes number of bytes to get
+ * @param out buffer receiving bytes
+ */
+ void (*get_bytes)(tls_prf_t *this, char *label, chunk_t seed,
+ size_t bytes, char *out);
+
+ /**
+ * Destroy a tls_prf_t.
+ */
+ void (*destroy)(tls_prf_t *this);
+};
+
+/**
+ * Create a tls_prf instance with specific algorithm as in TLS 1.2.
+ *
+ * @param hash underlying PRF function to use
+ * @return TLS PRF algorithm
+ */
+tls_prf_t *tls_prf_create_12(pseudo_random_function_t prf);
+
+/**
+ * Create a tls_prf instance with XOred SHA1/MD5 as in TLS 1.0/1.1.
+ *
+ * @return TLS PRF algorithm
+ */
+tls_prf_t *tls_prf_create_10();
+
+#endif /** TLS_PRF_H_ @}*/
projects / thirdparty / strongswan.git / commitdiff
