flm01/openwrt/package/luci/libs/nixio/axTLS/ssl/loader.c

466 lines
13 KiB
C
Raw Normal View History

/*
* Copyright (c) 2007, Cameron Rich
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of the axTLS project 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
*/
/**
* Load certificates/keys into memory. These can be in many different formats.
* PEM support and other formats can be processed here.
*
* The PEM private keys may be optionally encrypted with AES128 or AES256.
* The encrypted PEM keys were generated with something like:
*
* openssl genrsa -aes128 -passout pass:abcd -out axTLS.key_aes128.pem 512
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "ssl.h"
static int do_obj(SSL_CTX *ssl_ctx, int obj_type,
SSLObjLoader *ssl_obj, const char *password);
#ifdef CONFIG_SSL_HAS_PEM
static int ssl_obj_PEM_load(SSL_CTX *ssl_ctx, int obj_type,
SSLObjLoader *ssl_obj, const char *password);
#endif
/*
* Load a file into memory that is in binary DER (or ascii PEM) format.
*/
EXP_FUNC int STDCALL ssl_obj_load(SSL_CTX *ssl_ctx, int obj_type,
const char *filename, const char *password)
{
#ifndef CONFIG_SSL_SKELETON_MODE
static const char * const begin = "-----BEGIN";
int ret = SSL_OK;
SSLObjLoader *ssl_obj = NULL;
if (filename == NULL)
{
ret = SSL_ERROR_INVALID_KEY;
goto error;
}
ssl_obj = (SSLObjLoader *)calloc(1, sizeof(SSLObjLoader));
ssl_obj->len = get_file(filename, &ssl_obj->buf);
if (ssl_obj->len <= 0)
{
ret = SSL_ERROR_INVALID_KEY;
goto error;
}
/* is the file a PEM file? */
if (strncmp((char *)ssl_obj->buf, begin, strlen(begin)) == 0)
{
#ifdef CONFIG_SSL_HAS_PEM
ret = ssl_obj_PEM_load(ssl_ctx, obj_type, ssl_obj, password);
#else
printf(unsupported_str);
ret = SSL_ERROR_NOT_SUPPORTED;
#endif
}
else
ret = do_obj(ssl_ctx, obj_type, ssl_obj, password);
error:
ssl_obj_free(ssl_obj);
return ret;
#else
printf(unsupported_str);
return SSL_ERROR_NOT_SUPPORTED;
#endif /* CONFIG_SSL_SKELETON_MODE */
}
/*
* Transfer binary data into the object loader.
*/
EXP_FUNC int STDCALL ssl_obj_memory_load(SSL_CTX *ssl_ctx, int mem_type,
const uint8_t *data, int len, const char *password)
{
int ret;
SSLObjLoader *ssl_obj;
ssl_obj = (SSLObjLoader *)calloc(1, sizeof(SSLObjLoader));
ssl_obj->buf = (uint8_t *)malloc(len);
memcpy(ssl_obj->buf, data, len);
ssl_obj->len = len;
ret = do_obj(ssl_ctx, mem_type, ssl_obj, password);
ssl_obj_free(ssl_obj);
return ret;
}
/*
* Actually work out what we are doing
*/
static int do_obj(SSL_CTX *ssl_ctx, int obj_type,
SSLObjLoader *ssl_obj, const char *password)
{
int ret = SSL_OK;
switch (obj_type)
{
case SSL_OBJ_RSA_KEY:
ret = add_private_key(ssl_ctx, ssl_obj);
break;
case SSL_OBJ_X509_CERT:
ret = add_cert(ssl_ctx, ssl_obj->buf, ssl_obj->len);
break;
#ifdef CONFIG_SSL_CERT_VERIFICATION
case SSL_OBJ_X509_CACERT:
ret = add_cert_auth(ssl_ctx, ssl_obj->buf, ssl_obj->len);
break;
#endif
#ifdef CONFIG_SSL_USE_PKCS12
case SSL_OBJ_PKCS8:
ret = pkcs8_decode(ssl_ctx, ssl_obj, password);
break;
case SSL_OBJ_PKCS12:
ret = pkcs12_decode(ssl_ctx, ssl_obj, password);
break;
#endif
default:
printf(unsupported_str);
ret = SSL_ERROR_NOT_SUPPORTED;
break;
}
return ret;
}
/*
* Clean up our mess.
*/
void ssl_obj_free(SSLObjLoader *ssl_obj)
{
if (ssl_obj)
{
free(ssl_obj->buf);
free(ssl_obj);
}
}
/*
* Support for PEM encoded keys/certificates.
*/
#ifdef CONFIG_SSL_HAS_PEM
#define NUM_PEM_TYPES 3
#define IV_SIZE 16
#define IS_RSA_PRIVATE_KEY 0
#define IS_ENCRYPTED_PRIVATE_KEY 1
#define IS_CERTIFICATE 2
static const char * const begins[NUM_PEM_TYPES] =
{
"-----BEGIN RSA PRIVATE KEY-----",
"-----BEGIN ENCRYPTED PRIVATE KEY-----",
"-----BEGIN CERTIFICATE-----",
};
static const char * const ends[NUM_PEM_TYPES] =
{
"-----END RSA PRIVATE KEY-----",
"-----END ENCRYPTED PRIVATE KEY-----",
"-----END CERTIFICATE-----",
};
static const char * const aes_str[2] =
{
"DEK-Info: AES-128-CBC,",
"DEK-Info: AES-256-CBC,"
};
/**
* Take a base64 blob of data and decrypt it (using AES) into its
* proper ASN.1 form.
*/
static int pem_decrypt(const char *where, const char *end,
const char *password, SSLObjLoader *ssl_obj)
{
int ret = -1;
int is_aes_256 = 0;
char *start = NULL;
uint8_t iv[IV_SIZE];
int i, pem_size;
MD5_CTX md5_ctx;
AES_CTX aes_ctx;
uint8_t key[32]; /* AES256 size */
if (password == NULL || strlen(password) == 0)
{
#ifdef CONFIG_SSL_FULL_MODE
printf("Error: Need a password for this PEM file\n"); TTY_FLUSH();
#endif
goto error;
}
if ((start = strstr((const char *)where, aes_str[0]))) /* AES128? */
{
start += strlen(aes_str[0]);
}
else if ((start = strstr((const char *)where, aes_str[1]))) /* AES256? */
{
is_aes_256 = 1;
start += strlen(aes_str[1]);
}
else
{
#ifdef CONFIG_SSL_FULL_MODE
printf("Error: Unsupported password cipher\n"); TTY_FLUSH();
#endif
goto error;
}
/* convert from hex to binary - assumes uppercase hex */
for (i = 0; i < IV_SIZE; i++)
{
char c = *start++ - '0';
iv[i] = (c > 9 ? c + '0' - 'A' + 10 : c) << 4;
c = *start++ - '0';
iv[i] += (c > 9 ? c + '0' - 'A' + 10 : c);
}
while (*start == '\r' || *start == '\n')
start++;
/* turn base64 into binary */
pem_size = (int)(end-start);
if (base64_decode(start, pem_size, ssl_obj->buf, &ssl_obj->len) != 0)
goto error;
/* work out the key */
MD5_Init(&md5_ctx);
MD5_Update(&md5_ctx, (const uint8_t *)password, strlen(password));
MD5_Update(&md5_ctx, iv, SALT_SIZE);
MD5_Final(key, &md5_ctx);
if (is_aes_256)
{
MD5_Init(&md5_ctx);
MD5_Update(&md5_ctx, key, MD5_SIZE);
MD5_Update(&md5_ctx, (const uint8_t *)password, strlen(password));
MD5_Update(&md5_ctx, iv, SALT_SIZE);
MD5_Final(&key[MD5_SIZE], &md5_ctx);
}
/* decrypt using the key/iv */
AES_set_key(&aes_ctx, key, iv, is_aes_256 ? AES_MODE_256 : AES_MODE_128);
AES_convert_key(&aes_ctx);
AES_cbc_decrypt(&aes_ctx, ssl_obj->buf, ssl_obj->buf, ssl_obj->len);
ret = 0;
error:
return ret;
}
/**
* Take a base64 blob of data and turn it into its proper ASN.1 form.
*/
static int new_pem_obj(SSL_CTX *ssl_ctx, int is_cacert, char *where,
int remain, const char *password)
{
int ret = SSL_OK;
SSLObjLoader *ssl_obj = NULL;
int i, pem_size, obj_type;
char *start = NULL, *end = NULL;
for (i = 0; i < NUM_PEM_TYPES; i++)
{
if ((start = strstr(where, begins[i])) &&
(end = strstr(where, ends[i])))
{
remain -= (int)(end-start);
start += strlen(begins[i]);
pem_size = (int)(end-start);
ssl_obj = (SSLObjLoader *)calloc(1, sizeof(SSLObjLoader));
/* 4/3 bigger than what we need but so what */
ssl_obj->buf = (uint8_t *)calloc(1, pem_size);
if (i == IS_RSA_PRIVATE_KEY &&
strstr(start, "Proc-Type:") &&
strstr(start, "4,ENCRYPTED"))
{
/* check for encrypted PEM file */
if (pem_decrypt(start, end, password, ssl_obj) < 0)
goto error;
}
else if (base64_decode(start, pem_size,
ssl_obj->buf, &ssl_obj->len) != 0)
goto error;
switch (i)
{
case IS_RSA_PRIVATE_KEY:
obj_type = SSL_OBJ_RSA_KEY;
break;
case IS_ENCRYPTED_PRIVATE_KEY:
obj_type = SSL_OBJ_PKCS8;
break;
case IS_CERTIFICATE:
obj_type = is_cacert ?
SSL_OBJ_X509_CACERT : SSL_OBJ_X509_CERT;
break;
default:
goto error;
}
/* In a format we can now understand - so process it */
if ((ret = do_obj(ssl_ctx, obj_type, ssl_obj, password)))
goto error;
end += strlen(ends[i]);
remain -= strlen(ends[i]);
while (remain > 0 && (*end == '\r' || *end == '\n'))
{
end++;
remain--;
}
break;
}
}
if (i == NUM_PEM_TYPES)
goto error;
/* more PEM stuff to process? */
if (remain)
ret = new_pem_obj(ssl_ctx, is_cacert, end, remain, password);
error:
ssl_obj_free(ssl_obj);
return ret;
}
/*
* Load a file into memory that is in ASCII PEM format.
*/
static int ssl_obj_PEM_load(SSL_CTX *ssl_ctx, int obj_type,
SSLObjLoader *ssl_obj, const char *password)
{
char *start;
/* add a null terminator */
ssl_obj->len++;
ssl_obj->buf = (uint8_t *)realloc(ssl_obj->buf, ssl_obj->len);
ssl_obj->buf[ssl_obj->len-1] = 0;
start = (char *)ssl_obj->buf;
return new_pem_obj(ssl_ctx, obj_type == SSL_OBJ_X509_CACERT,
start, ssl_obj->len, password);
}
#endif /* CONFIG_SSL_HAS_PEM */
/**
* Load the key/certificates in memory depending on compile-time and user
* options.
*/
int load_key_certs(SSL_CTX *ssl_ctx)
{
int ret = SSL_OK;
uint32_t options = ssl_ctx->options;
#ifdef CONFIG_SSL_GENERATE_X509_CERT
uint8_t *cert_data = NULL;
int cert_size;
static const char *dn[] =
{
CONFIG_SSL_X509_COMMON_NAME,
CONFIG_SSL_X509_ORGANIZATION_NAME,
CONFIG_SSL_X509_ORGANIZATION_UNIT_NAME
};
#endif
/* do the private key first */
if (strlen(CONFIG_SSL_PRIVATE_KEY_LOCATION) > 0)
{
if ((ret = ssl_obj_load(ssl_ctx, SSL_OBJ_RSA_KEY,
CONFIG_SSL_PRIVATE_KEY_LOCATION,
CONFIG_SSL_PRIVATE_KEY_PASSWORD)) < 0)
goto error;
}
else if (!(options & SSL_NO_DEFAULT_KEY))
{
#if defined(CONFIG_SSL_USE_DEFAULT_KEY) || defined(CONFIG_SSL_SKELETON_MODE)
static const /* saves a few more bytes */
#include "private_key.h"
ssl_obj_memory_load(ssl_ctx, SSL_OBJ_RSA_KEY, default_private_key,
default_private_key_len, NULL);
#endif
}
/* now load the certificate */
#ifdef CONFIG_SSL_GENERATE_X509_CERT
if ((cert_size = ssl_x509_create(ssl_ctx, 0, dn, &cert_data)) < 0)
{
ret = cert_size;
goto error;
}
ssl_obj_memory_load(ssl_ctx, SSL_OBJ_X509_CERT, cert_data, cert_size, NULL);
free(cert_data);
#else
if (strlen(CONFIG_SSL_X509_CERT_LOCATION))
{
if ((ret = ssl_obj_load(ssl_ctx, SSL_OBJ_X509_CERT,
CONFIG_SSL_X509_CERT_LOCATION, NULL)) < 0)
goto error;
}
else if (!(options & SSL_NO_DEFAULT_KEY))
{
#if defined(CONFIG_SSL_USE_DEFAULT_KEY) || defined(CONFIG_SSL_SKELETON_MODE)
static const /* saves a few bytes and RAM */
#include "cert.h"
ssl_obj_memory_load(ssl_ctx, SSL_OBJ_X509_CERT,
default_certificate, default_certificate_len, NULL);
#endif
}
#endif
error:
#ifdef CONFIG_SSL_FULL_MODE
if (ret)
{
printf("Error: Certificate or key not loaded\n"); TTY_FLUSH();
}
#endif
return ret;
}