crypto_cryptoapi.c

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/*
 * Crypto wrapper for Microsoft CryptoAPI
 * Copyright (c) 2005-2009, Jouni Malinen <j@w1.fi>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Alternatively, this software may be distributed under the terms of BSD
 * license.
 *
 * See README and COPYING for more details.
 */

#include "includes.h"
#include <windows.h>
#include <wincrypt.h>

#include "common.h"
#include "crypto.h"

#ifndef MS_ENH_RSA_AES_PROV
#ifdef UNICODE
#define MS_ENH_RSA_AES_PROV \
L"Microsoft Enhanced RSA and AES Cryptographic Provider (Prototype)"
#else
#define MS_ENH_RSA_AES_PROV \
"Microsoft Enhanced RSA and AES Cryptographic Provider (Prototype)"
#endif
#endif /* MS_ENH_RSA_AES_PROV */

#ifndef CALG_HMAC
#define CALG_HMAC (ALG_CLASS_HASH | ALG_TYPE_ANY | ALG_SID_HMAC)
#endif

#ifdef __MINGW32_VERSION
/*
 * MinGW does not yet include all the needed definitions for CryptoAPI, so
 * define here whatever extra is needed.
 */

static BOOL WINAPI
(*CryptImportPublicKeyInfo)(HCRYPTPROV hCryptProv, DWORD dwCertEncodingType,
                            PCERT_PUBLIC_KEY_INFO pInfo, HCRYPTKEY *phKey)
= NULL; /* to be loaded from crypt32.dll */


static int mingw_load_crypto_func(void)
{
        HINSTANCE dll;

        /* MinGW does not yet have full CryptoAPI support, so load the needed
         * function here. */

        if (CryptImportPublicKeyInfo)
                return 0;

        dll = LoadLibrary("crypt32");
        if (dll == NULL) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: Could not load crypt32 "
                           "library");
                return -1;
        }

        CryptImportPublicKeyInfo = GetProcAddress(
                dll, "CryptImportPublicKeyInfo");
        if (CryptImportPublicKeyInfo == NULL) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: Could not get "
                           "CryptImportPublicKeyInfo() address from "
                           "crypt32 library");
                return -1;
        }

        return 0;
}

#else /* __MINGW32_VERSION */

static int mingw_load_crypto_func(void)
{
        return 0;
}

#endif /* __MINGW32_VERSION */


static void cryptoapi_report_error(const char *msg)
{
        char *s, *pos;
        DWORD err = GetLastError();

        if (FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
                          FORMAT_MESSAGE_FROM_SYSTEM,
                          NULL, err, 0, (LPTSTR) &s, 0, NULL) == 0) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: %s: %d", msg, (int) err);
        }

        pos = s;
        while (*pos) {
                if (*pos == '\n' || *pos == '\r') {
                        *pos = '\0';
                        break;
                }
                pos++;
        }

        wpa_printf(MSG_DEBUG, "CryptoAPI: %s: %d: (%s)", msg, (int) err, s);
        LocalFree(s);
}


int cryptoapi_hash_vector(ALG_ID alg, size_t hash_len, size_t num_elem,
                          const u8 *addr[], const size_t *len, u8 *mac)
{
        HCRYPTPROV prov;
        HCRYPTHASH hash;
        size_t i;
        DWORD hlen;
        int ret = 0;

        if (!CryptAcquireContext(&prov, NULL, NULL, PROV_RSA_FULL, 0)) {
                cryptoapi_report_error("CryptAcquireContext");
                return -1;
        }

        if (!CryptCreateHash(prov, alg, 0, 0, &hash)) {
                cryptoapi_report_error("CryptCreateHash");
                CryptReleaseContext(prov, 0);
                return -1;
        }

        for (i = 0; i < num_elem; i++) {
                if (!CryptHashData(hash, (BYTE *) addr[i], len[i], 0)) {
                        cryptoapi_report_error("CryptHashData");
                        CryptDestroyHash(hash);
                        CryptReleaseContext(prov, 0);
                }
        }

        hlen = hash_len;
        if (!CryptGetHashParam(hash, HP_HASHVAL, mac, &hlen, 0)) {
                cryptoapi_report_error("CryptGetHashParam");
                ret = -1;
        }

        CryptDestroyHash(hash);
        CryptReleaseContext(prov, 0);

        return ret;
}


int md4_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
        return cryptoapi_hash_vector(CALG_MD4, 16, num_elem, addr, len, mac);
}


void des_encrypt(const u8 *clear, const u8 *key, u8 *cypher)
{
        u8 next, tmp;
        int i;
        HCRYPTPROV prov;
        HCRYPTKEY ckey;
        DWORD dlen;
        struct {
                BLOBHEADER hdr;
                DWORD len;
                BYTE key[8];
        } key_blob;
        DWORD mode = CRYPT_MODE_ECB;

        key_blob.hdr.bType = PLAINTEXTKEYBLOB;
        key_blob.hdr.bVersion = CUR_BLOB_VERSION;
        key_blob.hdr.reserved = 0;
        key_blob.hdr.aiKeyAlg = CALG_DES;
        key_blob.len = 8;

        /* Add parity bits to the key */
        next = 0;
        for (i = 0; i < 7; i++) {
                tmp = key[i];
                key_blob.key[i] = (tmp >> i) | next | 1;
                next = tmp << (7 - i);
        }
        key_blob.key[i] = next | 1;

        if (!CryptAcquireContext(&prov, NULL, MS_ENHANCED_PROV, PROV_RSA_FULL,
                                 CRYPT_VERIFYCONTEXT)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: CryptAcquireContext failed: "
                           "%d", (int) GetLastError());
                return;
        }

        if (!CryptImportKey(prov, (BYTE *) &key_blob, sizeof(key_blob), 0, 0,
                            &ckey)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: CryptImportKey failed: %d",
                           (int) GetLastError());
                CryptReleaseContext(prov, 0);
                return;
        }

        if (!CryptSetKeyParam(ckey, KP_MODE, (BYTE *) &mode, 0)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: CryptSetKeyParam(KP_MODE) "
                           "failed: %d", (int) GetLastError());
                CryptDestroyKey(ckey);
                CryptReleaseContext(prov, 0);
                return;
        }

        os_memcpy(cypher, clear, 8);
        dlen = 8;
        if (!CryptEncrypt(ckey, 0, FALSE, 0, cypher, &dlen, 8)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: CryptEncrypt failed: %d",
                           (int) GetLastError());
                os_memset(cypher, 0, 8);
        }

        CryptDestroyKey(ckey);
        CryptReleaseContext(prov, 0);
}


int md5_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
        return cryptoapi_hash_vector(CALG_MD5, 16, num_elem, addr, len, mac);
}


int sha1_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
{
        return cryptoapi_hash_vector(CALG_SHA, 20, num_elem, addr, len, mac);
}


struct aes_context {
        HCRYPTPROV prov;
        HCRYPTKEY ckey;
};


void * aes_encrypt_init(const u8 *key, size_t len)
{
        struct aes_context *akey;
        struct {
                BLOBHEADER hdr;
                DWORD len;
                BYTE key[16];
        } key_blob;
        DWORD mode = CRYPT_MODE_ECB;

        if (len != 16)
                return NULL;

        key_blob.hdr.bType = PLAINTEXTKEYBLOB;
        key_blob.hdr.bVersion = CUR_BLOB_VERSION;
        key_blob.hdr.reserved = 0;
        key_blob.hdr.aiKeyAlg = CALG_AES_128;
        key_blob.len = len;
        os_memcpy(key_blob.key, key, len);

        akey = os_zalloc(sizeof(*akey));
        if (akey == NULL)
                return NULL;

        if (!CryptAcquireContext(&akey->prov, NULL,
                                 MS_ENH_RSA_AES_PROV, PROV_RSA_AES,
                                 CRYPT_VERIFYCONTEXT)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: CryptAcquireContext failed: "
                           "%d", (int) GetLastError());
                os_free(akey);
                return NULL;
        }

        if (!CryptImportKey(akey->prov, (BYTE *) &key_blob, sizeof(key_blob),
                            0, 0, &akey->ckey)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: CryptImportKey failed: %d",
                           (int) GetLastError());
                CryptReleaseContext(akey->prov, 0);
                os_free(akey);
                return NULL;
        }

        if (!CryptSetKeyParam(akey->ckey, KP_MODE, (BYTE *) &mode, 0)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: CryptSetKeyParam(KP_MODE) "
                           "failed: %d", (int) GetLastError());
                CryptDestroyKey(akey->ckey);
                CryptReleaseContext(akey->prov, 0);
                os_free(akey);
                return NULL;
        }

        return akey;
}


void aes_encrypt(void *ctx, const u8 *plain, u8 *crypt)
{
        struct aes_context *akey = ctx;
        DWORD dlen;

        os_memcpy(crypt, plain, 16);
        dlen = 16;
        if (!CryptEncrypt(akey->ckey, 0, FALSE, 0, crypt, &dlen, 16)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: CryptEncrypt failed: %d",
                           (int) GetLastError());
                os_memset(crypt, 0, 16);
        }
}


void aes_encrypt_deinit(void *ctx)
{
        struct aes_context *akey = ctx;
        if (akey) {
                CryptDestroyKey(akey->ckey);
                CryptReleaseContext(akey->prov, 0);
                os_free(akey);
        }
}


void * aes_decrypt_init(const u8 *key, size_t len)
{
        return aes_encrypt_init(key, len);
}


void aes_decrypt(void *ctx, const u8 *crypt, u8 *plain)
{
        struct aes_context *akey = ctx;
        DWORD dlen;

        os_memcpy(plain, crypt, 16);
        dlen = 16;

        if (!CryptDecrypt(akey->ckey, 0, FALSE, 0, plain, &dlen)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: CryptDecrypt failed: %d",
                           (int) GetLastError());
        }
}


void aes_decrypt_deinit(void *ctx)
{
        aes_encrypt_deinit(ctx);
}


struct crypto_hash {
        enum crypto_hash_alg alg;
        int error;
        HCRYPTPROV prov;
        HCRYPTHASH hash;
        HCRYPTKEY key;
};

struct crypto_hash * crypto_hash_init(enum crypto_hash_alg alg, const u8 *key,
                                      size_t key_len)
{
        struct crypto_hash *ctx;
        ALG_ID calg;
        struct {
                BLOBHEADER hdr;
                DWORD len;
                BYTE key[32];
        } key_blob;

        os_memset(&key_blob, 0, sizeof(key_blob));
        switch (alg) {
        case CRYPTO_HASH_ALG_MD5:
                calg = CALG_MD5;
                break;
        case CRYPTO_HASH_ALG_SHA1:
                calg = CALG_SHA;
                break;
        case CRYPTO_HASH_ALG_HMAC_MD5:
        case CRYPTO_HASH_ALG_HMAC_SHA1:
                calg = CALG_HMAC;
                key_blob.hdr.bType = PLAINTEXTKEYBLOB;
                key_blob.hdr.bVersion = CUR_BLOB_VERSION;
                key_blob.hdr.reserved = 0;
                /*
                 * Note: RC2 is not really used, but that can be used to
                 * import HMAC keys of up to 16 byte long.
                 * CRYPT_IPSEC_HMAC_KEY flag for CryptImportKey() is needed to
                 * be able to import longer keys (HMAC-SHA1 uses 20-byte key).
                 */
                key_blob.hdr.aiKeyAlg = CALG_RC2;
                key_blob.len = key_len;
                if (key_len > sizeof(key_blob.key))
                        return NULL;
                os_memcpy(key_blob.key, key, key_len);
                break;
        default:
                return NULL;
        }

        ctx = os_zalloc(sizeof(*ctx));
        if (ctx == NULL)
                return NULL;

        ctx->alg = alg;

        if (!CryptAcquireContext(&ctx->prov, NULL, NULL, PROV_RSA_FULL, 0)) {
                cryptoapi_report_error("CryptAcquireContext");
                os_free(ctx);
                return NULL;
        }

        if (calg == CALG_HMAC) {
#ifndef CRYPT_IPSEC_HMAC_KEY
#define CRYPT_IPSEC_HMAC_KEY 0x00000100
#endif
                if (!CryptImportKey(ctx->prov, (BYTE *) &key_blob,
                                    sizeof(key_blob), 0, CRYPT_IPSEC_HMAC_KEY,
                                    &ctx->key)) {
                        cryptoapi_report_error("CryptImportKey");
                        CryptReleaseContext(ctx->prov, 0);
                        os_free(ctx);
                        return NULL;
                }
        }

        if (!CryptCreateHash(ctx->prov, calg, ctx->key, 0, &ctx->hash)) {
                cryptoapi_report_error("CryptCreateHash");
                CryptReleaseContext(ctx->prov, 0);
                os_free(ctx);
                return NULL;
        }

        if (calg == CALG_HMAC) {
                HMAC_INFO info;
                os_memset(&info, 0, sizeof(info));
                switch (alg) {
                case CRYPTO_HASH_ALG_HMAC_MD5:
                        info.HashAlgid = CALG_MD5;
                        break;
                case CRYPTO_HASH_ALG_HMAC_SHA1:
                        info.HashAlgid = CALG_SHA;
                        break;
                default:
                        /* unreachable */
                        break;
                }

                if (!CryptSetHashParam(ctx->hash, HP_HMAC_INFO, (BYTE *) &info,
                                       0)) {
                        cryptoapi_report_error("CryptSetHashParam");
                        CryptDestroyHash(ctx->hash);
                        CryptReleaseContext(ctx->prov, 0);
                        os_free(ctx);
                        return NULL;
                }
        }

        return ctx;
}


void crypto_hash_update(struct crypto_hash *ctx, const u8 *data, size_t len)
{
        if (ctx == NULL || ctx->error)
                return;

        if (!CryptHashData(ctx->hash, (BYTE *) data, len, 0)) {
                cryptoapi_report_error("CryptHashData");
                ctx->error = 1;
        }
}


int crypto_hash_finish(struct crypto_hash *ctx, u8 *mac, size_t *len)
{
        int ret = 0;
        DWORD hlen;

        if (ctx == NULL)
                return -2;

        if (mac == NULL || len == NULL)
                goto done;

        if (ctx->error) {
                ret = -2;
                goto done;
        }

        hlen = *len;
        if (!CryptGetHashParam(ctx->hash, HP_HASHVAL, mac, &hlen, 0)) {
                cryptoapi_report_error("CryptGetHashParam");
                ret = -2;
        }
        *len = hlen;

done:
        if (ctx->alg == CRYPTO_HASH_ALG_HMAC_SHA1 ||
            ctx->alg == CRYPTO_HASH_ALG_HMAC_MD5)
                CryptDestroyKey(ctx->key);

        os_free(ctx);

        return ret;
}


struct crypto_cipher {
        HCRYPTPROV prov;
        HCRYPTKEY key;
};


struct crypto_cipher * crypto_cipher_init(enum crypto_cipher_alg alg,
                                          const u8 *iv, const u8 *key,
                                          size_t key_len)
{       
        struct crypto_cipher *ctx;
        struct {
                BLOBHEADER hdr;
                DWORD len;
                BYTE key[32];
        } key_blob;
        DWORD mode = CRYPT_MODE_CBC;

        key_blob.hdr.bType = PLAINTEXTKEYBLOB;
        key_blob.hdr.bVersion = CUR_BLOB_VERSION;
        key_blob.hdr.reserved = 0;
        key_blob.len = key_len;
        if (key_len > sizeof(key_blob.key))
                return NULL;
        os_memcpy(key_blob.key, key, key_len);

        switch (alg) {
        case CRYPTO_CIPHER_ALG_AES:
                if (key_len == 32)
                        key_blob.hdr.aiKeyAlg = CALG_AES_256;
                else if (key_len == 24)
                        key_blob.hdr.aiKeyAlg = CALG_AES_192;
                else
                        key_blob.hdr.aiKeyAlg = CALG_AES_128;
                break;
        case CRYPTO_CIPHER_ALG_3DES:
                key_blob.hdr.aiKeyAlg = CALG_3DES;
                break;
        case CRYPTO_CIPHER_ALG_DES:
                key_blob.hdr.aiKeyAlg = CALG_DES;
                break;
        case CRYPTO_CIPHER_ALG_RC2:
                key_blob.hdr.aiKeyAlg = CALG_RC2;
                break;
        case CRYPTO_CIPHER_ALG_RC4:
                key_blob.hdr.aiKeyAlg = CALG_RC4;
                break;
        default:
                return NULL;
        }

        ctx = os_zalloc(sizeof(*ctx));
        if (ctx == NULL)
                return NULL;

        if (!CryptAcquireContext(&ctx->prov, NULL, MS_ENH_RSA_AES_PROV,
                                 PROV_RSA_AES, CRYPT_VERIFYCONTEXT)) {
                cryptoapi_report_error("CryptAcquireContext");
                goto fail1;
        }

        if (!CryptImportKey(ctx->prov, (BYTE *) &key_blob,
                            sizeof(key_blob), 0, 0, &ctx->key)) {
                cryptoapi_report_error("CryptImportKey");
                goto fail2;
        }

        if (!CryptSetKeyParam(ctx->key, KP_MODE, (BYTE *) &mode, 0)) {
                cryptoapi_report_error("CryptSetKeyParam(KP_MODE)");
                goto fail3;
        }

        if (iv && !CryptSetKeyParam(ctx->key, KP_IV, (BYTE *) iv, 0)) {
                cryptoapi_report_error("CryptSetKeyParam(KP_IV)");
                goto fail3;
        }

        return ctx;

fail3:
        CryptDestroyKey(ctx->key);
fail2:
        CryptReleaseContext(ctx->prov, 0);
fail1:
        os_free(ctx);
        return NULL;
}


int crypto_cipher_encrypt(struct crypto_cipher *ctx, const u8 *plain,
                          u8 *crypt, size_t len)
{
        DWORD dlen;

        os_memcpy(crypt, plain, len);
        dlen = len;
        if (!CryptEncrypt(ctx->key, 0, FALSE, 0, crypt, &dlen, len)) {
                cryptoapi_report_error("CryptEncrypt");
                os_memset(crypt, 0, len);
                return -1;
        }

        return 0;
}


int crypto_cipher_decrypt(struct crypto_cipher *ctx, const u8 *crypt,
                          u8 *plain, size_t len)
{
        DWORD dlen;

        os_memcpy(plain, crypt, len);
        dlen = len;
        if (!CryptDecrypt(ctx->key, 0, FALSE, 0, plain, &dlen)) {
                cryptoapi_report_error("CryptDecrypt");
                return -1;
        }

        return 0;
}


void crypto_cipher_deinit(struct crypto_cipher *ctx)
{
        CryptDestroyKey(ctx->key);
        CryptReleaseContext(ctx->prov, 0);
        os_free(ctx);
}


struct crypto_public_key {
        HCRYPTPROV prov;
        HCRYPTKEY rsa;
};

struct crypto_private_key {
        HCRYPTPROV prov;
        HCRYPTKEY rsa;
};


struct crypto_public_key * crypto_public_key_import(const u8 *key, size_t len)
{
        /* Use crypto_public_key_from_cert() instead. */
        return NULL;
}


struct crypto_private_key * crypto_private_key_import(const u8 *key,
                                                      size_t len,
                                                      const char *passwd)
{
        /* TODO */
        return NULL;
}


struct crypto_public_key * crypto_public_key_from_cert(const u8 *buf,
                                                       size_t len)
{
        struct crypto_public_key *pk;
        PCCERT_CONTEXT cc;

        pk = os_zalloc(sizeof(*pk));
        if (pk == NULL)
                return NULL;

        cc = CertCreateCertificateContext(X509_ASN_ENCODING |
                                          PKCS_7_ASN_ENCODING, buf, len);
        if (!cc) {
                cryptoapi_report_error("CryptCreateCertificateContext");
                os_free(pk);
                return NULL;
        }

        if (!CryptAcquireContext(&pk->prov, NULL, MS_DEF_PROV, PROV_RSA_FULL,
                                 0)) {
                cryptoapi_report_error("CryptAcquireContext");
                os_free(pk);
                CertFreeCertificateContext(cc);
                return NULL;
        }

        if (!CryptImportPublicKeyInfo(pk->prov, X509_ASN_ENCODING |
                                      PKCS_7_ASN_ENCODING,
                                      &cc->pCertInfo->SubjectPublicKeyInfo,
                                      &pk->rsa)) {
                cryptoapi_report_error("CryptImportPublicKeyInfo");
                CryptReleaseContext(pk->prov, 0);
                os_free(pk);
                CertFreeCertificateContext(cc);
                return NULL;
        }

        CertFreeCertificateContext(cc);

        return pk;
}


int crypto_public_key_encrypt_pkcs1_v15(struct crypto_public_key *key,
                                        const u8 *in, size_t inlen,
                                        u8 *out, size_t *outlen)
{
        DWORD clen;
        u8 *tmp;
        size_t i;

        if (*outlen < inlen)
                return -1;
        tmp = malloc(*outlen);
        if (tmp == NULL)
                return -1;

        os_memcpy(tmp, in, inlen);
        clen = inlen;
        if (!CryptEncrypt(key->rsa, 0, TRUE, 0, tmp, &clen, *outlen)) {
                wpa_printf(MSG_DEBUG, "CryptoAPI: Failed to encrypt using "
                           "public key: %d", (int) GetLastError());
                os_free(tmp);
                return -1;
        }

        *outlen = clen;

        /* Reverse the output */
        for (i = 0; i < *outlen; i++)
                out[i] = tmp[*outlen - 1 - i];

        os_free(tmp);

        return 0;
}


int crypto_private_key_sign_pkcs1(struct crypto_private_key *key,
                                  const u8 *in, size_t inlen,
                                  u8 *out, size_t *outlen)
{
        /* TODO */
        return -1;
}


void crypto_public_key_free(struct crypto_public_key *key)
{
        if (key) {
                CryptDestroyKey(key->rsa);
                CryptReleaseContext(key->prov, 0);
                os_free(key);
        }
}


void crypto_private_key_free(struct crypto_private_key *key)
{
        if (key) {
                CryptDestroyKey(key->rsa);
                CryptReleaseContext(key->prov, 0);
                os_free(key);
        }
}


int crypto_global_init(void)
{
        return mingw_load_crypto_func();
}


void crypto_global_deinit(void)
{
}


int crypto_mod_exp(const u8 *base, size_t base_len,
                   const u8 *power, size_t power_len,
                   const u8 *modulus, size_t modulus_len,
                   u8 *result, size_t *result_len)
{
        /* TODO */
        return -1;
}