/*
- * Copyright (C) 2005-2006 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2005-2007 Andre Noll <maan@systemlinux.org>
*
- * 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.
- *
- * 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.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
+ * Licensed under the GPL v2. For licencing details see COPYING.
*/
/** \file crypt.c openssl-based RSA encryption/decryption routines */
-#include <openssl/pem.h>
#include "para.h"
#include "error.h"
#include "string.h"
-
-/** \cond used to distinguish between loading of private/public key */
-#define LOAD_PUBLIC_KEY 0
-#define LOAD_PRIVATE_KEY 1
-/** \endcond **/
+#include "crypt.h"
static EVP_PKEY *load_key(const char *file, int private)
{
return pkey;
}
-static int get_key(char *key_file, RSA **rsa, int private)
+/**
+ * read an RSA key from a file
+ *
+ * \param key_file the file containing the key
+ * \param rsa RSA structure is returned here
+ * \param private if non-zero, read the private key, otherwise the public key
+ *
+ * \return The size of the RSA key on success, negative on errors.
+ *
+ * \sa openssl(1), rsa(1).
+ */
+int get_rsa_key(char *key_file, RSA **rsa, int private)
{
EVP_PKEY *key = load_key(key_file, private);
if (!key)
- return (private == LOAD_PRIVATE_KEY)? -E_PRIVATE_KEY : -E_PUBLIC_KEY;
+ return (private == LOAD_PRIVATE_KEY)? -E_PRIVATE_KEY
+ : -E_PUBLIC_KEY;
*rsa = EVP_PKEY_get1_RSA(key);
EVP_PKEY_free(key);
if (!*rsa)
return RSA_size(*rsa);
}
+/**
+ * free an RSA structure
+ *
+ * \param rsa pointer to the RSA struct to free
+ *
+ * This must be called for any key obtained by get_rsa_key().
+ */
+void rsa_free(RSA *rsa)
+{
+ if (rsa)
+ RSA_free(rsa);
+}
+
/**
* decrypt a buffer using an RSA key
*
* \sa RSA_private_decrypt(3)
**/
int para_decrypt_buffer(char *key_file, unsigned char *outbuf, unsigned char *inbuf,
- int rsa_inlen)
+ unsigned rsa_inlen)
{
RSA *rsa;
- int ret = get_key(key_file, &rsa, LOAD_PRIVATE_KEY);
+ int ret, inlen = rsa_inlen;
+ if (inlen < 0)
+ return -E_RSA;
+ ret = get_rsa_key(key_file, &rsa, LOAD_PRIVATE_KEY);
if (ret < 0)
return ret;
- ret = RSA_private_decrypt(rsa_inlen, inbuf, outbuf, rsa, RSA_PKCS1_PADDING);
+ ret = RSA_private_decrypt(inlen, inbuf, outbuf, rsa, RSA_PKCS1_PADDING);
+ rsa_free(rsa);
return (ret > 0)? ret : -E_DECRYPT;
}
* \sa para_decrypt_buffer()
*/
int para_decrypt_challenge(char *key_file, long unsigned *challenge_nr,
- unsigned char *inbuf, int rsa_inlen)
+ unsigned char *inbuf, unsigned rsa_inlen)
{
- unsigned char *rsa_out = OPENSSL_malloc(128);
+ unsigned char *rsa_out = OPENSSL_malloc(rsa_inlen + 1);
int ret = para_decrypt_buffer(key_file, rsa_out, inbuf, rsa_inlen);
- if (ret >= 0)
+ if (ret >= 0) {
+ rsa_out[ret] = '\0';
ret = sscanf((char *)rsa_out, "%lu", challenge_nr) == 1?
1 : -E_CHALLENGE;
+ }
OPENSSL_free(rsa_out);
return ret;
}
/**
* encrypt a buffer using an RSA key
*
- * \param key_file full path of the rsa key
+ * \param rsa: public rsa key
* \param inbuf the input buffer
* \param len the length of \a inbuf
* \param outbuf the output buffer
*
* \sa RSA_public_encrypt(3)
*/
-int para_encrypt_buffer(char *key_file, unsigned char *inbuf,
- const unsigned len, unsigned char *outbuf)
+int para_encrypt_buffer(RSA *rsa, unsigned char *inbuf,
+ unsigned len, unsigned char *outbuf)
{
- RSA *rsa;
- int ret = get_key(key_file, &rsa, LOAD_PUBLIC_KEY);
+ int ret, flen = len; /* RSA_public_encrypt expects a signed int */
- if (ret < 0)
- return ret;
- ret = RSA_public_encrypt(len, inbuf, outbuf, rsa, RSA_PKCS1_PADDING);
+ if (flen < 0)
+ return -E_ENCRYPT;
+ ret = RSA_public_encrypt(flen, inbuf, outbuf, rsa, RSA_PKCS1_PADDING);
return ret < 0? -E_ENCRYPT : ret;
}
/**
* encrypt the given challenge number
*
- * \param key_file full path of the rsa key
+ * \param rsa: public rsa key
* \param challenge_nr the number to be encrypted
* \param outbuf the output buffer
*
* \sa para_encrypt_buffer()
*
*/
-int para_encrypt_challenge(char *key_file, long unsigned challenge_nr,
+int para_encrypt_challenge(RSA* rsa, long unsigned challenge_nr,
unsigned char *outbuf)
{
unsigned char *inbuf = (unsigned char*) make_message("%lu", challenge_nr);
- int ret = para_encrypt_buffer(key_file, inbuf, strlen((char *)inbuf), outbuf);
+ int ret = para_encrypt_buffer(rsa, inbuf, strlen((char *)inbuf), outbuf);
free(inbuf);
return ret;
}
projects / paraslash.git / blobdiff