From 8dd0350e1607aa30f7a043c8d5ec7a7eeb874115 Mon Sep 17 00:00:00 2001 From: Alberto Gonzalez Iniesta Date: Mon, 5 Nov 2012 16:28:09 +0100 Subject: Imported Upstream version 2.3_rc1 --- src/openvpn/cryptoapi.c | 465 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 465 insertions(+) create mode 100644 src/openvpn/cryptoapi.c (limited to 'src/openvpn/cryptoapi.c') diff --git a/src/openvpn/cryptoapi.c b/src/openvpn/cryptoapi.c new file mode 100644 index 0000000..b7fc11e --- /dev/null +++ b/src/openvpn/cryptoapi.c @@ -0,0 +1,465 @@ +/* + * Copyright (c) 2004 Peter 'Luna' Runestig + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modifi- + * cation, are permitted provided that the following conditions are met: + * + * o Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * o Redistributions in binary form must reproduce the above copyright no- + * tice, this list of conditions and the following disclaimer in the do- + * cumentation and/or other materials provided with the distribution. + * + * o The names of the contributors may not 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 REGENTS OR CONTRIBUTORS BE LI- + * ABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUEN- + * TIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEV- + * ER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABI- + * LITY, 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. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#elif defined(_MSC_VER) +#include "config-msvc.h" +#endif + +#include "syshead.h" + +#ifdef ENABLE_CRYPTOAPI + +#include +#include +#include +#include +#include +#include +#include + +/* MinGW w32api 3.17 is still incomplete when it comes to CryptoAPI while + * MinGW32-w64 defines all macros used. This is a hack around that problem. + */ +#ifndef CERT_SYSTEM_STORE_LOCATION_SHIFT +#define CERT_SYSTEM_STORE_LOCATION_SHIFT 16 +#endif +#ifndef CERT_SYSTEM_STORE_CURRENT_USER_ID +#define CERT_SYSTEM_STORE_CURRENT_USER_ID 1 +#endif +#ifndef CERT_SYSTEM_STORE_CURRENT_USER +#define CERT_SYSTEM_STORE_CURRENT_USER (CERT_SYSTEM_STORE_CURRENT_USER_ID << CERT_SYSTEM_STORE_LOCATION_SHIFT) +#endif +#ifndef CERT_STORE_READONLY_FLAG +#define CERT_STORE_READONLY_FLAG 0x00008000 +#endif +#ifndef CERT_STORE_OPEN_EXISTING_FLAG +#define CERT_STORE_OPEN_EXISTING_FLAG 0x00004000 +#endif + +/* Size of an SSL signature: MD5+SHA1 */ +#define SSL_SIG_LENGTH 36 + +/* try to funnel any Windows/CryptoAPI error messages to OpenSSL ERR_... */ +#define ERR_LIB_CRYPTOAPI (ERR_LIB_USER + 69) /* 69 is just a number... */ +#define CRYPTOAPIerr(f) err_put_ms_error(GetLastError(), (f), __FILE__, __LINE__) +#define CRYPTOAPI_F_CERT_OPEN_SYSTEM_STORE 100 +#define CRYPTOAPI_F_CERT_FIND_CERTIFICATE_IN_STORE 101 +#define CRYPTOAPI_F_CRYPT_ACQUIRE_CERTIFICATE_PRIVATE_KEY 102 +#define CRYPTOAPI_F_CRYPT_CREATE_HASH 103 +#define CRYPTOAPI_F_CRYPT_GET_HASH_PARAM 104 +#define CRYPTOAPI_F_CRYPT_SET_HASH_PARAM 105 +#define CRYPTOAPI_F_CRYPT_SIGN_HASH 106 +#define CRYPTOAPI_F_LOAD_LIBRARY 107 +#define CRYPTOAPI_F_GET_PROC_ADDRESS 108 + +static ERR_STRING_DATA CRYPTOAPI_str_functs[] = { + { ERR_PACK(ERR_LIB_CRYPTOAPI, 0, 0), "microsoft cryptoapi"}, + { ERR_PACK(0, CRYPTOAPI_F_CERT_OPEN_SYSTEM_STORE, 0), "CertOpenSystemStore" }, + { ERR_PACK(0, CRYPTOAPI_F_CERT_FIND_CERTIFICATE_IN_STORE, 0), "CertFindCertificateInStore" }, + { ERR_PACK(0, CRYPTOAPI_F_CRYPT_ACQUIRE_CERTIFICATE_PRIVATE_KEY, 0), "CryptAcquireCertificatePrivateKey" }, + { ERR_PACK(0, CRYPTOAPI_F_CRYPT_CREATE_HASH, 0), "CryptCreateHash" }, + { ERR_PACK(0, CRYPTOAPI_F_CRYPT_GET_HASH_PARAM, 0), "CryptGetHashParam" }, + { ERR_PACK(0, CRYPTOAPI_F_CRYPT_SET_HASH_PARAM, 0), "CryptSetHashParam" }, + { ERR_PACK(0, CRYPTOAPI_F_CRYPT_SIGN_HASH, 0), "CryptSignHash" }, + { ERR_PACK(0, CRYPTOAPI_F_LOAD_LIBRARY, 0), "LoadLibrary" }, + { ERR_PACK(0, CRYPTOAPI_F_GET_PROC_ADDRESS, 0), "GetProcAddress" }, + { 0, NULL } +}; + +typedef struct _CAPI_DATA { + const CERT_CONTEXT *cert_context; + HCRYPTPROV crypt_prov; + DWORD key_spec; + BOOL free_crypt_prov; +} CAPI_DATA; + +static char *ms_error_text(DWORD ms_err) +{ + LPVOID lpMsgBuf = NULL; + char *rv = NULL; + + FormatMessage( + FORMAT_MESSAGE_ALLOCATE_BUFFER | + FORMAT_MESSAGE_FROM_SYSTEM | + FORMAT_MESSAGE_IGNORE_INSERTS, + NULL, ms_err, + MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), /* Default language */ + (LPTSTR) &lpMsgBuf, 0, NULL); + if (lpMsgBuf) { + char *p; + rv = strdup(lpMsgBuf); + LocalFree(lpMsgBuf); + /* trim to the left */ + if (rv) + for (p = rv + strlen(rv) - 1; p >= rv; p--) { + if (isspace(*p)) + *p = '\0'; + else + break; + } + } + return rv; +} + +static void err_put_ms_error(DWORD ms_err, int func, const char *file, int line) +{ + static int init = 0; +# define ERR_MAP_SZ 16 + static struct { + int err; + DWORD ms_err; /* I don't think we get more than 16 *different* errors */ + } err_map[ERR_MAP_SZ]; /* in here, before we give up the whole thing... */ + int i; + + if (ms_err == 0) + /* 0 is not an error */ + return; + if (!init) { + ERR_load_strings(ERR_LIB_CRYPTOAPI, CRYPTOAPI_str_functs); + memset(&err_map, 0, sizeof(err_map)); + init++; + } + /* since MS error codes are 32 bit, and the ones in the ERR_... system is + * only 12, we must have a mapping table between them. */ + for (i = 0; i < ERR_MAP_SZ; i++) { + if (err_map[i].ms_err == ms_err) { + ERR_PUT_error(ERR_LIB_CRYPTOAPI, func, err_map[i].err, file, line); + break; + } else if (err_map[i].ms_err == 0 ) { + /* end of table, add new entry */ + ERR_STRING_DATA *esd = calloc(2, sizeof(*esd)); + if (esd == NULL) + break; + err_map[i].ms_err = ms_err; + err_map[i].err = esd->error = i + 100; + esd->string = ms_error_text(ms_err); + ERR_load_strings(ERR_LIB_CRYPTOAPI, esd); + ERR_PUT_error(ERR_LIB_CRYPTOAPI, func, err_map[i].err, file, line); + break; + } + } +} + +/* encrypt */ +static int rsa_pub_enc(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding) +{ + /* I haven't been able to trigger this one, but I want to know if it happens... */ + assert(0); + + return 0; +} + +/* verify arbitrary data */ +static int rsa_pub_dec(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding) +{ + /* I haven't been able to trigger this one, but I want to know if it happens... */ + assert(0); + + return 0; +} + +/* sign arbitrary data */ +static int rsa_priv_enc(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding) +{ + CAPI_DATA *cd = (CAPI_DATA *) rsa->meth->app_data; + HCRYPTHASH hash; + DWORD hash_size, len, i; + unsigned char *buf; + + if (cd == NULL) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_PASSED_NULL_PARAMETER); + return 0; + } + if (padding != RSA_PKCS1_PADDING) { + /* AFAICS, CryptSignHash() *always* uses PKCS1 padding. */ + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, RSA_R_UNKNOWN_PADDING_TYPE); + return 0; + } + /* Unfortunately, there is no "CryptSign()" function in CryptoAPI, that would + * be way to straightforward for M$, I guess... So we have to do it this + * tricky way instead, by creating a "Hash", and load the already-made hash + * from 'from' into it. */ + /* For now, we only support NID_md5_sha1 */ + if (flen != SSL_SIG_LENGTH) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, RSA_R_INVALID_MESSAGE_LENGTH); + return 0; + } + if (!CryptCreateHash(cd->crypt_prov, CALG_SSL3_SHAMD5, 0, 0, &hash)) { + CRYPTOAPIerr(CRYPTOAPI_F_CRYPT_CREATE_HASH); + return 0; + } + len = sizeof(hash_size); + if (!CryptGetHashParam(hash, HP_HASHSIZE, (BYTE *) &hash_size, &len, 0)) { + CRYPTOAPIerr(CRYPTOAPI_F_CRYPT_GET_HASH_PARAM); + CryptDestroyHash(hash); + return 0; + } + if ((int) hash_size != flen) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, RSA_R_INVALID_MESSAGE_LENGTH); + CryptDestroyHash(hash); + return 0; + } + if (!CryptSetHashParam(hash, HP_HASHVAL, (BYTE * ) from, 0)) { + CRYPTOAPIerr(CRYPTOAPI_F_CRYPT_SET_HASH_PARAM); + CryptDestroyHash(hash); + return 0; + } + + len = RSA_size(rsa); + buf = malloc(len); + if (buf == NULL) { + RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_MALLOC_FAILURE); + CryptDestroyHash(hash); + return 0; + } + if (!CryptSignHash(hash, cd->key_spec, NULL, 0, buf, &len)) { + CRYPTOAPIerr(CRYPTOAPI_F_CRYPT_SIGN_HASH); + CryptDestroyHash(hash); + free(buf); + return 0; + } + /* and now, we have to reverse the byte-order in the result from CryptSignHash()... */ + for (i = 0; i < len; i++) + to[i] = buf[len - i - 1]; + free(buf); + + CryptDestroyHash(hash); + return len; +} + +/* decrypt */ +static int rsa_priv_dec(int flen, const unsigned char *from, unsigned char *to, RSA *rsa, int padding) +{ + /* I haven't been able to trigger this one, but I want to know if it happens... */ + assert(0); + + return 0; +} + +/* called at RSA_new */ +static int init(RSA *rsa) +{ + + return 0; +} + +/* called at RSA_free */ +static int finish(RSA *rsa) +{ + CAPI_DATA *cd = (CAPI_DATA *) rsa->meth->app_data; + + if (cd == NULL) + return 0; + if (cd->crypt_prov && cd->free_crypt_prov) + CryptReleaseContext(cd->crypt_prov, 0); + if (cd->cert_context) + CertFreeCertificateContext(cd->cert_context); + free(rsa->meth->app_data); + free((char *) rsa->meth); + rsa->meth = NULL; + return 1; +} + +static const CERT_CONTEXT *find_certificate_in_store(const char *cert_prop, HCERTSTORE cert_store) +{ + /* Find, and use, the desired certificate from the store. The + * 'cert_prop' certificate search string can look like this: + * SUBJ: + * THUMB:, e.g. + * THUMB:f6 49 24 41 01 b4 fb 44 0c ce f4 36 ae d0 c4 c9 df 7a b6 28 + */ + const CERT_CONTEXT *rv = NULL; + + if (!strncmp(cert_prop, "SUBJ:", 5)) { + /* skip the tag */ + cert_prop += 5; + rv = CertFindCertificateInStore(cert_store, X509_ASN_ENCODING | PKCS_7_ASN_ENCODING, + 0, CERT_FIND_SUBJECT_STR_A, cert_prop, NULL); + + } else if (!strncmp(cert_prop, "THUMB:", 6)) { + unsigned char hash[255]; + char *p; + int i, x = 0; + CRYPT_HASH_BLOB blob; + + /* skip the tag */ + cert_prop += 6; + for (p = (char *) cert_prop, i = 0; *p && i < sizeof(hash); i++) { + if (*p >= '0' && *p <= '9') + x = (*p - '0') << 4; + else if (*p >= 'A' && *p <= 'F') + x = (*p - 'A' + 10) << 4; + else if (*p >= 'a' && *p <= 'f') + x = (*p - 'a' + 10) << 4; + if (!*++p) /* unexpected end of string */ + break; + if (*p >= '0' && *p <= '9') + x += *p - '0'; + else if (*p >= 'A' && *p <= 'F') + x += *p - 'A' + 10; + else if (*p >= 'a' && *p <= 'f') + x += *p - 'a' + 10; + hash[i] = x; + /* skip any space(s) between hex numbers */ + for (p++; *p && *p == ' '; p++); + } + blob.cbData = i; + blob.pbData = (unsigned char *) &hash; + rv = CertFindCertificateInStore(cert_store, X509_ASN_ENCODING | PKCS_7_ASN_ENCODING, + 0, CERT_FIND_HASH, &blob, NULL); + + } + + return rv; +} + +int SSL_CTX_use_CryptoAPI_certificate(SSL_CTX *ssl_ctx, const char *cert_prop) +{ + HCERTSTORE cs; + X509 *cert = NULL; + RSA *rsa = NULL, *pub_rsa; + CAPI_DATA *cd = calloc(1, sizeof(*cd)); + RSA_METHOD *my_rsa_method = calloc(1, sizeof(*my_rsa_method)); + + if (cd == NULL || my_rsa_method == NULL) { + SSLerr(SSL_F_SSL_CTX_USE_CERTIFICATE_FILE, ERR_R_MALLOC_FAILURE); + goto err; + } + /* search CURRENT_USER first, then LOCAL_MACHINE */ + cs = CertOpenStore((LPCSTR) CERT_STORE_PROV_SYSTEM, 0, 0, CERT_SYSTEM_STORE_CURRENT_USER | + CERT_STORE_OPEN_EXISTING_FLAG | CERT_STORE_READONLY_FLAG, L"MY"); + if (cs == NULL) { + CRYPTOAPIerr(CRYPTOAPI_F_CERT_OPEN_SYSTEM_STORE); + goto err; + } + cd->cert_context = find_certificate_in_store(cert_prop, cs); + CertCloseStore(cs, 0); + if (!cd->cert_context) { + cs = CertOpenStore((LPCSTR) CERT_STORE_PROV_SYSTEM, 0, 0, CERT_SYSTEM_STORE_LOCAL_MACHINE | + CERT_STORE_OPEN_EXISTING_FLAG | CERT_STORE_READONLY_FLAG, L"MY"); + if (cs == NULL) { + CRYPTOAPIerr(CRYPTOAPI_F_CERT_OPEN_SYSTEM_STORE); + goto err; + } + cd->cert_context = find_certificate_in_store(cert_prop, cs); + CertCloseStore(cs, 0); + if (cd->cert_context == NULL) { + CRYPTOAPIerr(CRYPTOAPI_F_CERT_FIND_CERTIFICATE_IN_STORE); + goto err; + } + } + + /* cert_context->pbCertEncoded is the cert X509 DER encoded. */ + cert = d2i_X509(NULL, (const unsigned char **) &cd->cert_context->pbCertEncoded, + cd->cert_context->cbCertEncoded); + if (cert == NULL) { + SSLerr(SSL_F_SSL_CTX_USE_CERTIFICATE_FILE, ERR_R_ASN1_LIB); + goto err; + } + + /* set up stuff to use the private key */ + if (!CryptAcquireCertificatePrivateKey(cd->cert_context, CRYPT_ACQUIRE_COMPARE_KEY_FLAG, + NULL, &cd->crypt_prov, &cd->key_spec, &cd->free_crypt_prov)) { + /* if we don't have a smart card reader here, and we try to access a + * smart card certificate, we get: + * "Error 1223: The operation was canceled by the user." */ + CRYPTOAPIerr(CRYPTOAPI_F_CRYPT_ACQUIRE_CERTIFICATE_PRIVATE_KEY); + goto err; + } + /* here we don't need to do CryptGetUserKey() or anything; all necessary key + * info is in cd->cert_context, and then, in cd->crypt_prov. */ + + my_rsa_method->name = "Microsoft CryptoAPI RSA Method"; + my_rsa_method->rsa_pub_enc = rsa_pub_enc; + my_rsa_method->rsa_pub_dec = rsa_pub_dec; + my_rsa_method->rsa_priv_enc = rsa_priv_enc; + my_rsa_method->rsa_priv_dec = rsa_priv_dec; + /* my_rsa_method->init = init; */ + my_rsa_method->finish = finish; + my_rsa_method->flags = RSA_METHOD_FLAG_NO_CHECK; + my_rsa_method->app_data = (char *) cd; + + rsa = RSA_new(); + if (rsa == NULL) { + SSLerr(SSL_F_SSL_CTX_USE_CERTIFICATE_FILE, ERR_R_MALLOC_FAILURE); + goto err; + } + + /* cert->cert_info->key->pkey is NULL until we call SSL_CTX_use_certificate(), + * so we do it here then... */ + if (!SSL_CTX_use_certificate(ssl_ctx, cert)) + goto err; + /* the public key */ + pub_rsa = cert->cert_info->key->pkey->pkey.rsa; + /* SSL_CTX_use_certificate() increased the reference count in 'cert', so + * we decrease it here with X509_free(), or it will never be cleaned up. */ + X509_free(cert); + cert = NULL; + + /* I'm not sure about what we have to fill in in the RSA, trying out stuff... */ + /* rsa->n indicates the key size */ + rsa->n = BN_dup(pub_rsa->n); + rsa->flags |= RSA_FLAG_EXT_PKEY; + if (!RSA_set_method(rsa, my_rsa_method)) + goto err; + + if (!SSL_CTX_use_RSAPrivateKey(ssl_ctx, rsa)) + goto err; + /* SSL_CTX_use_RSAPrivateKey() increased the reference count in 'rsa', so + * we decrease it here with RSA_free(), or it will never be cleaned up. */ + RSA_free(rsa); + return 1; + + err: + if (cert) + X509_free(cert); + if (rsa) + RSA_free(rsa); + else { + if (my_rsa_method) + free(my_rsa_method); + if (cd) { + if (cd->free_crypt_prov && cd->crypt_prov) + CryptReleaseContext(cd->crypt_prov, 0); + if (cd->cert_context) + CertFreeCertificateContext(cd->cert_context); + free(cd); + } + } + return 0; +} + +#else +#ifdef _MSC_VER /* Dummy function needed to avoid empty file compiler warning in Microsoft VC */ +static void dummy (void) {} +#endif +#endif /* WIN32 */ -- cgit v1.2.3