scard.c - third_party/openssh-portable - Git at Google

 /*
  * Copyright (c) 2001 Markus Friedl.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. 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.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
  */

 #include "includes.h"
 #ifdef SMARTCARD
 RCSID("$OpenBSD: scard.c,v 1.15 2001/09/28 09:49:31 djm Exp $");

 #include <openssl/engine.h>
 #include <sectok.h>

 #include "key.h"
 #include "log.h"
 #include "xmalloc.h"
 #include "scard.h"

 #define CLA_SSH 0x05
 #define INS_DECRYPT 0x10
 #define INS_GET_KEYLENGTH 0x20
 #define INS_GET_PUBKEY 0x30
 #define INS_GET_RESPONSE 0xc0

 #define MAX_BUF_SIZE 256

 static int sc_fd = -1;
 static char *sc_reader_id = NULL;
 static int cla = 0x00;	/* class */

 /* interface to libsectok */

 static int
 sc_open(void)
 {
 	int sw;

 	if (sc_fd >= 0)
 		return sc_fd;

 	sc_fd = sectok_friendly_open(sc_reader_id, STONOWAIT, &sw);
 	if (sc_fd < 0) {
 		error("sectok_open failed: %s", sectok_get_sw(sw));
 		return SCARD_ERROR_FAIL;
 	}
 	if (! sectok_cardpresent(sc_fd)) {
 		debug("smartcard in reader %s not present, skipping",
 		    sc_reader_id);
 		sc_close();
 		return SCARD_ERROR_NOCARD;
 	}
 	if (sectok_reset(sc_fd, 0, NULL, &sw) <= 0) {
 		error("sectok_reset failed: %s", sectok_get_sw(sw));
 		sc_fd = -1;
 		return SCARD_ERROR_FAIL;
 	}
 	if ((cla = cyberflex_inq_class(sc_fd)) < 0)
 		cla = 0;

 	debug("sc_open ok %d", sc_fd);
 	return sc_fd;
 }

 static int
 sc_enable_applet(void)
 {
 	static u_char aid[] = {0xfc, 0x53, 0x73, 0x68, 0x2e, 0x62, 0x69, 0x6e};
 	int sw = 0;

 	/* select applet id */
 	sectok_apdu(sc_fd, cla, 0xa4, 0x04, 0, sizeof aid, aid, 0, NULL, &sw);
 	if (!sectok_swOK(sw)) {
 		error("sectok_apdu failed: %s", sectok_get_sw(sw));
 		sc_close();
 		return -1;
 	}
 	return 0;
 }

 static int
 sc_init(void)
 {
 	int status;

 	status = sc_open();
 	if (status == SCARD_ERROR_NOCARD) {
 		return SCARD_ERROR_NOCARD;
 	}
 	if (status < 0 ) {
 		error("sc_open failed");
 		return status;
 	}
 	if (sc_enable_applet() < 0) {
 		error("sc_enable_applet failed");
 		return SCARD_ERROR_APPLET;
 	}
 	return 0;
 }

 static int
 sc_read_pubkey(Key * k)
 {
 	u_char buf[2], *n;
 	char *p;
 	int len, sw, status = -1;

 	len = sw = 0;
 	n = NULL;

 	if (sc_fd < 0) {
 		status = sc_init();
 		if (status < 0 )
 			goto err;
 	}

 	/* get key size */
 	sectok_apdu(sc_fd, CLA_SSH, INS_GET_KEYLENGTH, 0, 0, 0, NULL,
 	     sizeof(buf), buf, &sw);
 	if (!sectok_swOK(sw)) {
 		error("could not obtain key length: %s", sectok_get_sw(sw));
 		goto err;
 	}
 	len = (buf[0] << 8) | buf[1];
 	len /= 8;
 	debug("INS_GET_KEYLENGTH: len %d sw %s", len, sectok_get_sw(sw));

 	n = xmalloc(len);
 	/* get n */
 	sectok_apdu(sc_fd, CLA_SSH, INS_GET_PUBKEY, 0, 0, 0, NULL, len, n, &sw);
 	if (!sectok_swOK(sw)) {
 		error("could not obtain public key: %s", sectok_get_sw(sw));
 		goto err;
 	}

 	debug("INS_GET_KEYLENGTH: sw %s", sectok_get_sw(sw));

 	if (BN_bin2bn(n, len, k->rsa->n) == NULL) {
 		error("c_read_pubkey: BN_bin2bn failed");
 		goto err;
 	}

 	/* currently the java applet just stores 'n' */
 	if (!BN_set_word(k->rsa->e, 35)) {
 		error("c_read_pubkey: BN_set_word(e, 35) failed");
 		goto err;
 	}

 	status = 0;
 	p = key_fingerprint(k, SSH_FP_MD5, SSH_FP_HEX);
 	debug("fingerprint %d %s", key_size(k), p);
 	xfree(p);

 err:
 	if (n != NULL)
 		xfree(n);
 	sc_close();
 	return status;
 }

 /* private key operations */

 static int
 sc_private_decrypt(int flen, u_char *from, u_char *to, RSA *rsa, int padding)
 {
 	u_char *padded = NULL;
 	int sw, len, olen, status = -1;

 	debug("sc_private_decrypt called");

 	olen = len = sw = 0;
 	if (sc_fd < 0) {
 		status = sc_init();
 		if (status < 0 )
 			goto err;
 	}
 	if (padding != RSA_PKCS1_PADDING)
 		goto err;

 	len = BN_num_bytes(rsa->n);
 	padded = xmalloc(len);

 	sectok_apdu(sc_fd, CLA_SSH, INS_DECRYPT, 0, 0, len, from, 0, NULL, &sw);
 	if (!sectok_swOK(sw)) {
 		error("sc_private_decrypt: INS_DECRYPT failed: %s",
 		    sectok_get_sw(sw));
 		goto err;
 	}
 	sectok_apdu(sc_fd, CLA_SSH, INS_GET_RESPONSE, 0, 0, 0, NULL,
 	     len, padded, &sw);
 	if (!sectok_swOK(sw)) {
 		error("sc_private_decrypt: INS_GET_RESPONSE failed: %s",
 		    sectok_get_sw(sw));
 		goto err;
 	}
 	olen = RSA_padding_check_PKCS1_type_2(to, len, padded + 1, len - 1,
 	    len);
 err:
 	if (padded)
 		xfree(padded);
 	sc_close();
 	return (olen >= 0 ? olen : status);
 }

 static int
 sc_private_encrypt(int flen, u_char *from, u_char *to, RSA *rsa, int padding)
 {
 	u_char *padded = NULL;
 	int sw, len, status = -1;

 	len = sw = 0;
 	if (sc_fd < 0) {
 		status = sc_init();
 		if (status < 0 )
 			goto err;
 	}
 	if (padding != RSA_PKCS1_PADDING)
 		goto err;

 	debug("sc_private_encrypt called");
 	len = BN_num_bytes(rsa->n);
 	padded = xmalloc(len);

 	if (RSA_padding_add_PKCS1_type_1(padded, len, from, flen) <= 0) {
 		error("RSA_padding_add_PKCS1_type_1 failed");
 		goto err;
 	}
 	sectok_apdu(sc_fd, CLA_SSH, INS_DECRYPT, 0, 0, len, padded, 0, NULL, &sw);
 	if (!sectok_swOK(sw)) {
 		error("sc_private_decrypt: INS_DECRYPT failed: %s",
 		    sectok_get_sw(sw));
 		goto err;
 	}
 	sectok_apdu(sc_fd, CLA_SSH, INS_GET_RESPONSE, 0, 0, 0, NULL,
 	     len, to, &sw);
 	if (!sectok_swOK(sw)) {
 		error("sc_private_decrypt: INS_GET_RESPONSE failed: %s",
 		    sectok_get_sw(sw));
 		goto err;
 	}
 err:
 	if (padded)
 		xfree(padded);
 	sc_close();
 	return (len >= 0 ? len : status);
 }

 /* called on free */

 static int (*orig_finish)(RSA *rsa) = NULL;

 static int
 sc_finish(RSA *rsa)
 {
 	if (orig_finish)
 		orig_finish(rsa);
 	sc_close();
 	return 1;
 }


 /* engine for overloading private key operations */

 static ENGINE *smart_engine = NULL;
 static RSA_METHOD smart_rsa =
 {
 	"sectok",
 	NULL,
 	NULL,
 	NULL,
 	NULL,
 	NULL,
 	NULL,
 	NULL,
 	NULL,
 	0,
 	NULL,
 };

 ENGINE *
 sc_get_engine(void)
 {
 	RSA_METHOD *def;

 	def = RSA_get_default_openssl_method();

 	/* overload */
 	smart_rsa.rsa_priv_enc	= sc_private_encrypt;
 	smart_rsa.rsa_priv_dec	= sc_private_decrypt;

 	/* save original */
 	orig_finish		= def->finish;
 	smart_rsa.finish	= sc_finish;

 	/* just use the OpenSSL version */
 	smart_rsa.rsa_pub_enc   = def->rsa_pub_enc;
 	smart_rsa.rsa_pub_dec   = def->rsa_pub_dec;
 	smart_rsa.rsa_mod_exp	= def->rsa_mod_exp;
 	smart_rsa.bn_mod_exp	= def->bn_mod_exp;
 	smart_rsa.init		= def->init;
 	smart_rsa.flags		= def->flags;
 	smart_rsa.app_data	= def->app_data;
 	smart_rsa.rsa_sign	= def->rsa_sign;
 	smart_rsa.rsa_verify	= def->rsa_verify;

 	smart_engine = ENGINE_new();

 	ENGINE_set_id(smart_engine, "sectok");
 	ENGINE_set_name(smart_engine, "libsectok");
 	ENGINE_set_RSA(smart_engine, &smart_rsa);
 	ENGINE_set_DSA(smart_engine, DSA_get_default_openssl_method());
 	ENGINE_set_DH(smart_engine, DH_get_default_openssl_method());
 	ENGINE_set_RAND(smart_engine, RAND_SSLeay());
 	ENGINE_set_BN_mod_exp(smart_engine, BN_mod_exp);

 	return smart_engine;
 }

 void
 sc_close(void)
 {
 	if (sc_fd >= 0) {
 		sectok_close(sc_fd);
 		sc_fd = -1;
 	}
 }

 Key *
 sc_get_key(const char *id)
 {
 	Key *k;
 	int status;

 	if (sc_reader_id != NULL)
 		xfree(sc_reader_id);
 	sc_reader_id = xstrdup(id);

 	k = key_new(KEY_RSA);
 	if (k == NULL) {
 		return NULL;
 	}
 	status = sc_read_pubkey(k);
 	if (status == SCARD_ERROR_NOCARD) {
 		key_free(k);
 		return NULL;
 	}
 	if (status < 0 ) {
 		error("sc_read_pubkey failed");
 		key_free(k);
 		return NULL;
 	}
 	return k;
 }
 #endif /* SMARTCARD */
	/*
	* Copyright (c) 2001 Markus Friedl. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. 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.
	*
	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
	*/

	#include "includes.h"
	#ifdef SMARTCARD
	RCSID("$OpenBSD: scard.c,v 1.15 2001/09/28 09:49:31 djm Exp $");

	#include <openssl/engine.h>
	#include <sectok.h>

	#include "key.h"
	#include "log.h"
	#include "xmalloc.h"
	#include "scard.h"

	#define CLA_SSH 0x05
	#define INS_DECRYPT 0x10
	#define INS_GET_KEYLENGTH 0x20
	#define INS_GET_PUBKEY 0x30
	#define INS_GET_RESPONSE 0xc0

	#define MAX_BUF_SIZE 256

	static int sc_fd = -1;
	static char *sc_reader_id = NULL;
	static int cla = 0x00; /* class */

	/* interface to libsectok */

	static int
	sc_open(void)
	{
	int sw;

	if (sc_fd >= 0)
	return sc_fd;

	sc_fd = sectok_friendly_open(sc_reader_id, STONOWAIT, &sw);
	if (sc_fd < 0) {
	error("sectok_open failed: %s", sectok_get_sw(sw));
	return SCARD_ERROR_FAIL;
	}
	if (! sectok_cardpresent(sc_fd)) {
	debug("smartcard in reader %s not present, skipping",
	sc_reader_id);
	sc_close();
	return SCARD_ERROR_NOCARD;
	}
	if (sectok_reset(sc_fd, 0, NULL, &sw) <= 0) {
	error("sectok_reset failed: %s", sectok_get_sw(sw));
	sc_fd = -1;
	return SCARD_ERROR_FAIL;
	}
	if ((cla = cyberflex_inq_class(sc_fd)) < 0)
	cla = 0;

	debug("sc_open ok %d", sc_fd);
	return sc_fd;
	}

	static int
	sc_enable_applet(void)
	{
	static u_char aid[] = {0xfc, 0x53, 0x73, 0x68, 0x2e, 0x62, 0x69, 0x6e};
	int sw = 0;

	/* select applet id */
	sectok_apdu(sc_fd, cla, 0xa4, 0x04, 0, sizeof aid, aid, 0, NULL, &sw);
	if (!sectok_swOK(sw)) {
	error("sectok_apdu failed: %s", sectok_get_sw(sw));
	sc_close();
	return -1;
	}
	return 0;
	}

	static int
	sc_init(void)
	{
	int status;

	status = sc_open();
	if (status == SCARD_ERROR_NOCARD) {
	return SCARD_ERROR_NOCARD;
	}
	if (status < 0 ) {
	error("sc_open failed");
	return status;
	}
	if (sc_enable_applet() < 0) {
	error("sc_enable_applet failed");
	return SCARD_ERROR_APPLET;
	}
	return 0;
	}

	static int
	sc_read_pubkey(Key * k)
	{
	u_char buf[2], *n;
	char *p;
	int len, sw, status = -1;

	len = sw = 0;
	n = NULL;

	if (sc_fd < 0) {
	status = sc_init();
	if (status < 0 )
	goto err;
	}

	/* get key size */
	sectok_apdu(sc_fd, CLA_SSH, INS_GET_KEYLENGTH, 0, 0, 0, NULL,
	sizeof(buf), buf, &sw);
	if (!sectok_swOK(sw)) {
	error("could not obtain key length: %s", sectok_get_sw(sw));
	goto err;
	}
	len = (buf[0] << 8) \| buf[1];
	len /= 8;
	debug("INS_GET_KEYLENGTH: len %d sw %s", len, sectok_get_sw(sw));

	n = xmalloc(len);
	/* get n */
	sectok_apdu(sc_fd, CLA_SSH, INS_GET_PUBKEY, 0, 0, 0, NULL, len, n, &sw);
	if (!sectok_swOK(sw)) {
	error("could not obtain public key: %s", sectok_get_sw(sw));
	goto err;
	}

	debug("INS_GET_KEYLENGTH: sw %s", sectok_get_sw(sw));

	if (BN_bin2bn(n, len, k->rsa->n) == NULL) {
	error("c_read_pubkey: BN_bin2bn failed");
	goto err;
	}

	/* currently the java applet just stores 'n' */
	if (!BN_set_word(k->rsa->e, 35)) {
	error("c_read_pubkey: BN_set_word(e, 35) failed");
	goto err;
	}

	status = 0;
	p = key_fingerprint(k, SSH_FP_MD5, SSH_FP_HEX);
	debug("fingerprint %d %s", key_size(k), p);
	xfree(p);

	err:
	if (n != NULL)
	xfree(n);
	sc_close();
	return status;
	}

	/* private key operations */

	static int
	sc_private_decrypt(int flen, u_char from, u_char to, RSA *rsa, int padding)
	{
	u_char *padded = NULL;
	int sw, len, olen, status = -1;

	debug("sc_private_decrypt called");

	olen = len = sw = 0;
	if (sc_fd < 0) {
	status = sc_init();
	if (status < 0 )
	goto err;
	}
	if (padding != RSA_PKCS1_PADDING)
	goto err;

	len = BN_num_bytes(rsa->n);
	padded = xmalloc(len);

	sectok_apdu(sc_fd, CLA_SSH, INS_DECRYPT, 0, 0, len, from, 0, NULL, &sw);
	if (!sectok_swOK(sw)) {
	error("sc_private_decrypt: INS_DECRYPT failed: %s",
	sectok_get_sw(sw));
	goto err;
	}
	sectok_apdu(sc_fd, CLA_SSH, INS_GET_RESPONSE, 0, 0, 0, NULL,
	len, padded, &sw);
	if (!sectok_swOK(sw)) {
	error("sc_private_decrypt: INS_GET_RESPONSE failed: %s",
	sectok_get_sw(sw));
	goto err;
	}
	olen = RSA_padding_check_PKCS1_type_2(to, len, padded + 1, len - 1,
	len);
	err:
	if (padded)
	xfree(padded);
	sc_close();
	return (olen >= 0 ? olen : status);
	}

	static int
	sc_private_encrypt(int flen, u_char from, u_char to, RSA *rsa, int padding)
	{
	u_char *padded = NULL;
	int sw, len, status = -1;

	len = sw = 0;
	if (sc_fd < 0) {
	status = sc_init();
	if (status < 0 )
	goto err;
	}
	if (padding != RSA_PKCS1_PADDING)
	goto err;

	debug("sc_private_encrypt called");
	len = BN_num_bytes(rsa->n);
	padded = xmalloc(len);

	if (RSA_padding_add_PKCS1_type_1(padded, len, from, flen) <= 0) {
	error("RSA_padding_add_PKCS1_type_1 failed");
	goto err;
	}
	sectok_apdu(sc_fd, CLA_SSH, INS_DECRYPT, 0, 0, len, padded, 0, NULL, &sw);
	if (!sectok_swOK(sw)) {
	error("sc_private_decrypt: INS_DECRYPT failed: %s",
	sectok_get_sw(sw));
	goto err;
	}
	sectok_apdu(sc_fd, CLA_SSH, INS_GET_RESPONSE, 0, 0, 0, NULL,
	len, to, &sw);
	if (!sectok_swOK(sw)) {
	error("sc_private_decrypt: INS_GET_RESPONSE failed: %s",
	sectok_get_sw(sw));
	goto err;
	}
	err:
	if (padded)
	xfree(padded);
	sc_close();
	return (len >= 0 ? len : status);
	}

	/* called on free */

	static int (orig_finish)(RSA rsa) = NULL;

	static int
	sc_finish(RSA *rsa)
	{
	if (orig_finish)
	orig_finish(rsa);
	sc_close();
	return 1;
	}


	/* engine for overloading private key operations */

	static ENGINE *smart_engine = NULL;
	static RSA_METHOD smart_rsa =
	{
	"sectok",
	NULL,
	NULL,
	NULL,
	NULL,
	NULL,
	NULL,
	NULL,
	NULL,
	0,
	NULL,
	};

	ENGINE *
	sc_get_engine(void)
	{
	RSA_METHOD *def;

	def = RSA_get_default_openssl_method();

	/* overload */
	smart_rsa.rsa_priv_enc = sc_private_encrypt;
	smart_rsa.rsa_priv_dec = sc_private_decrypt;

	/* save original */
	orig_finish = def->finish;
	smart_rsa.finish = sc_finish;

	/* just use the OpenSSL version */
	smart_rsa.rsa_pub_enc = def->rsa_pub_enc;
	smart_rsa.rsa_pub_dec = def->rsa_pub_dec;
	smart_rsa.rsa_mod_exp = def->rsa_mod_exp;
	smart_rsa.bn_mod_exp = def->bn_mod_exp;
	smart_rsa.init = def->init;
	smart_rsa.flags = def->flags;
	smart_rsa.app_data = def->app_data;
	smart_rsa.rsa_sign = def->rsa_sign;
	smart_rsa.rsa_verify = def->rsa_verify;

	smart_engine = ENGINE_new();

	ENGINE_set_id(smart_engine, "sectok");
	ENGINE_set_name(smart_engine, "libsectok");
	ENGINE_set_RSA(smart_engine, &smart_rsa);
	ENGINE_set_DSA(smart_engine, DSA_get_default_openssl_method());
	ENGINE_set_DH(smart_engine, DH_get_default_openssl_method());
	ENGINE_set_RAND(smart_engine, RAND_SSLeay());
	ENGINE_set_BN_mod_exp(smart_engine, BN_mod_exp);

	return smart_engine;
	}

	void
	sc_close(void)
	{
	if (sc_fd >= 0) {
	sectok_close(sc_fd);
	sc_fd = -1;
	}
	}

	Key *
	sc_get_key(const char *id)
	{
	Key *k;
	int status;

	if (sc_reader_id != NULL)
	xfree(sc_reader_id);
	sc_reader_id = xstrdup(id);

	k = key_new(KEY_RSA);
	if (k == NULL) {
	return NULL;
	}
	status = sc_read_pubkey(k);
	if (status == SCARD_ERROR_NOCARD) {
	key_free(k);
	return NULL;
	}
	if (status < 0 ) {
	error("sc_read_pubkey failed");
	key_free(k);
	return NULL;
	}
	return k;
	}
	#endif /* SMARTCARD */