text: /*
   * TLSv1 client - write handshake message
   * Copyright (c) 2006-2014, Jouni Malinen <j@w1.fi>
   *
   * This software may be distributed under the terms of the BSD license.
   * See README for more details.
   */
  
  #include "includes.h"
  
  #include "common.h"
  #include "crypto/md5.h"
  #include "crypto/sha1.h"
  #include "crypto/sha256.h"
  #include "crypto/tls.h"
  #include "crypto/random.h"
  #include "x509v3.h"
  #include "tlsv1_common.h"
  #include "tlsv1_record.h"
  #include "tlsv1_client.h"
  #include "tlsv1_client_i.h"
  
  
  static size_t tls_client_cert_chain_der_len(struct tlsv1_client *conn)
  {
  	size_t len = 0;
  	struct x509_certificate *cert;
  
  	if (conn->cred == NULL)
  		return 0;
  
  	cert = conn->cred->cert;
  	while (cert) {
  		len += 3 + cert->cert_len;
  		if (x509_certificate_self_signed(cert))
  			break;
  		cert = x509_certificate_get_subject(conn->cred->trusted_certs,
  						    &cert->issuer);
  	}
  
  	return len;
  }
  
  
  u8 * tls_send_client_hello(struct tlsv1_client *conn, size_t *out_len)
  {
  	u8 *hello, *end, *pos, *hs_length, *hs_start, *rhdr;
  	struct os_time now;
  	size_t len, i;
  
  	wpa_printf(MSG_DEBUG, "TLSv1: Send ClientHello");
  	*out_len = 0;
  
  	os_get_time(&now);
  	WPA_PUT_BE32(conn->client_random, now.sec);
  	if (random_get_bytes(conn->client_random + 4, TLS_RANDOM_LEN - 4)) {
  		wpa_printf(MSG_ERROR, "TLSv1: Could not generate "
  			   "client_random");
  		return NULL;
  	}
  	wpa_hexdump(MSG_MSGDUMP, "TLSv1: client_random",
  		    conn->client_random, TLS_RANDOM_LEN);
  
  	len = 100 + conn->num_cipher_suites * 2 + conn->client_hello_ext_len;
  	hello = os_malloc(len);
  	if (hello == NULL)
  		return NULL;
  	end = hello + len;
  
  	rhdr = hello;
  	pos = rhdr + TLS_RECORD_HEADER_LEN;
  
  	/* opaque fragment[TLSPlaintext.length] */
  
  	/* Handshake */
  	hs_start = pos;
  	/* HandshakeType msg_type */
  	*pos++ = TLS_HANDSHAKE_TYPE_CLIENT_HELLO;
  	/* uint24 length (to be filled) */
  	hs_length = pos;
  	pos += 3;
  	/* body - ClientHello */
  	/* ProtocolVersion client_version */
  	WPA_PUT_BE16(pos, TLS_VERSION);
  	pos += 2;
  	/* Random random: uint32 gmt_unix_time, opaque random_bytes */
  	os_memcpy(pos, conn->client_random, TLS_RANDOM_LEN);
  	pos += TLS_RANDOM_LEN;
  	/* SessionID session_id */
  	*pos++ = conn->session_id_len;
  	os_memcpy(pos, conn->session_id, conn->session_id_len);
  	pos += conn->session_id_len;
  	/* CipherSuite cipher_suites<2..2^16-1> */
  	WPA_PUT_BE16(pos, 2 * conn->num_cipher_suites);
  	pos += 2;
  	for (i = 0; i < conn->num_cipher_suites; i++) {
  		WPA_PUT_BE16(pos, conn->cipher_suites[i]);
  		pos += 2;
  	}
  	/* CompressionMethod compression_methods<1..2^8-1> */
  	*pos++ = 1;
  	*pos++ = TLS_COMPRESSION_NULL;
  
  	if (conn->client_hello_ext) {
  		os_memcpy(pos, conn->client_hello_ext,
  			  conn->client_hello_ext_len);
  		pos += conn->client_hello_ext_len;
  	}
  
  	WPA_PUT_BE24(hs_length, pos - hs_length - 3);
  	tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
  
  	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
  			      rhdr, end - rhdr, hs_start, pos - hs_start,
  			      out_len) < 0) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to create TLS record");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		os_free(hello);
  		return NULL;
  	}
  
  	conn->state = SERVER_HELLO;
  
  	return hello;
  }
  
  
  static int tls_write_client_certificate(struct tlsv1_client *conn,
  					u8 **msgpos, u8 *end)
  {
  	u8 *pos, *rhdr, *hs_start, *hs_length, *cert_start;
  	size_t rlen;
  	struct x509_certificate *cert;
  
  	pos = *msgpos;
  
  	wpa_printf(MSG_DEBUG, "TLSv1: Send Certificate");
  	rhdr = pos;
  	pos += TLS_RECORD_HEADER_LEN;
  
  	/* opaque fragment[TLSPlaintext.length] */
  
  	/* Handshake */
  	hs_start = pos;
  	/* HandshakeType msg_type */
  	*pos++ = TLS_HANDSHAKE_TYPE_CERTIFICATE;
  	/* uint24 length (to be filled) */
  	hs_length = pos;
  	pos += 3;
  	/* body - Certificate */
  	/* uint24 length (to be filled) */
  	cert_start = pos;
  	pos += 3;
  	cert = conn->cred ? conn->cred->cert : NULL;
  	while (cert) {
  		if (pos + 3 + cert->cert_len > end) {
  			wpa_printf(MSG_DEBUG, "TLSv1: Not enough buffer space "
  				   "for Certificate (cert_len=%lu left=%lu)",
  				   (unsigned long) cert->cert_len,
  				   (unsigned long) (end - pos));
  			tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  				  TLS_ALERT_INTERNAL_ERROR);
  			return -1;
  		}
  		WPA_PUT_BE24(pos, cert->cert_len);
  		pos += 3;
  		os_memcpy(pos, cert->cert_start, cert->cert_len);
  		pos += cert->cert_len;
  
  		if (x509_certificate_self_signed(cert))
  			break;
  		cert = x509_certificate_get_subject(conn->cred->trusted_certs,
  						    &cert->issuer);
  	}
  	if (conn->cred == NULL || cert == conn->cred->cert || cert == NULL) {
  		/*
  		 * Client was not configured with all the needed certificates
  		 * to form a full certificate chain. The server may fail to
  		 * validate the chain unless it is configured with all the
  		 * missing CA certificates.
  		 */
  		wpa_printf(MSG_DEBUG, "TLSv1: Full client certificate chain "
  			   "not configured - validation may fail");
  	}
  	WPA_PUT_BE24(cert_start, pos - cert_start - 3);
  
  	WPA_PUT_BE24(hs_length, pos - hs_length - 3);
  
  	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
  			      rhdr, end - rhdr, hs_start, pos - hs_start,
  			      &rlen) < 0) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate a record");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  	pos = rhdr + rlen;
  
  	tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
  
  	*msgpos = pos;
  
  	return 0;
  }
  
  
  static int tlsv1_key_x_dh(struct tlsv1_client *conn, u8 **pos, u8 *end)
  {
  	/* ClientDiffieHellmanPublic */
  	u8 *csecret, *csecret_start, *dh_yc, *shared;
  	size_t csecret_len, dh_yc_len, shared_len;
  
  	csecret_len = conn->dh_p_len;
  	csecret = os_malloc(csecret_len);
  	if (csecret == NULL) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to allocate "
  			   "memory for Yc (Diffie-Hellman)");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  	if (random_get_bytes(csecret, csecret_len)) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to get random "
  			   "data for Diffie-Hellman");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		os_free(csecret);
  		return -1;
  	}
  
  	if (os_memcmp(csecret, conn->dh_p, csecret_len) > 0)
  		csecret[0] = 0; /* make sure Yc < p */
  
  	csecret_start = csecret;
  	while (csecret_len > 1 && *csecret_start == 0) {
  		csecret_start++;
  		csecret_len--;
  	}
  	wpa_hexdump_key(MSG_DEBUG, "TLSv1: DH client's secret value",
  			csecret_start, csecret_len);
  
  	/* Yc = g^csecret mod p */
  	dh_yc_len = conn->dh_p_len;
  	dh_yc = os_malloc(dh_yc_len);
  	if (dh_yc == NULL) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to allocate "
  			   "memory for Diffie-Hellman");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		os_free(csecret);
  		return -1;
  	}
  	if (crypto_mod_exp(conn->dh_g, conn->dh_g_len,
  			   csecret_start, csecret_len,
  			   conn->dh_p, conn->dh_p_len,
  			   dh_yc, &dh_yc_len)) {
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		os_free(csecret);
  		os_free(dh_yc);
  		return -1;
  	}
  
  	wpa_hexdump(MSG_DEBUG, "TLSv1: DH Yc (client's public value)",
  		    dh_yc, dh_yc_len);
  
  	WPA_PUT_BE16(*pos, dh_yc_len);
  	*pos += 2;
  	if (*pos + dh_yc_len > end) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Not enough room in the "
  			   "message buffer for Yc");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		os_free(csecret);
  		os_free(dh_yc);
  		return -1;
  	}
  	os_memcpy(*pos, dh_yc, dh_yc_len);
  	*pos += dh_yc_len;
  	os_free(dh_yc);
  
  	shared_len = conn->dh_p_len;
  	shared = os_malloc(shared_len);
  	if (shared == NULL) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Could not allocate memory for "
  			   "DH");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		os_free(csecret);
  		return -1;
  	}
  
  	/* shared = Ys^csecret mod p */
  	if (crypto_mod_exp(conn->dh_ys, conn->dh_ys_len,
  			   csecret_start, csecret_len,
  			   conn->dh_p, conn->dh_p_len,
  			   shared, &shared_len)) {
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		os_free(csecret);
  		os_free(shared);
  		return -1;
  	}
  	wpa_hexdump_key(MSG_DEBUG, "TLSv1: Shared secret from DH key exchange",
  			shared, shared_len);
  
  	os_memset(csecret_start, 0, csecret_len);
  	os_free(csecret);
  	if (tls_derive_keys(conn, shared, shared_len)) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive keys");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		os_free(shared);
  		return -1;
  	}
  	os_memset(shared, 0, shared_len);
  	os_free(shared);
  	tlsv1_client_free_dh(conn);
  	return 0;
  }
  
  
  static int tlsv1_key_x_rsa(struct tlsv1_client *conn, u8 **pos, u8 *end)
  {
  	u8 pre_master_secret[TLS_PRE_MASTER_SECRET_LEN];
  	size_t clen;
  	int res;
  
  	if (tls_derive_pre_master_secret(pre_master_secret) < 0 ||
  	    tls_derive_keys(conn, pre_master_secret,
  			    TLS_PRE_MASTER_SECRET_LEN)) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive keys");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  
  	/* EncryptedPreMasterSecret */
  	if (conn->server_rsa_key == NULL) {
  		wpa_printf(MSG_DEBUG, "TLSv1: No server RSA key to "
  			   "use for encrypting pre-master secret");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  
  	/* RSA encrypted value is encoded with PKCS #1 v1.5 block type 2. */
  	*pos += 2;
  	clen = end - *pos;
  	res = crypto_public_key_encrypt_pkcs1_v15(
  		conn->server_rsa_key,
  		pre_master_secret, TLS_PRE_MASTER_SECRET_LEN,
  		*pos, &clen);
  	os_memset(pre_master_secret, 0, TLS_PRE_MASTER_SECRET_LEN);
  	if (res < 0) {
  		wpa_printf(MSG_DEBUG, "TLSv1: RSA encryption failed");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  	WPA_PUT_BE16(*pos - 2, clen);
  	wpa_hexdump(MSG_MSGDUMP, "TLSv1: Encrypted pre_master_secret",
  		    *pos, clen);
  	*pos += clen;
  
  	return 0;
  }
  
  
  static int tls_write_client_key_exchange(struct tlsv1_client *conn,
  					 u8 **msgpos, u8 *end)
  {
  	u8 *pos, *rhdr, *hs_start, *hs_length;
  	size_t rlen;
  	tls_key_exchange keyx;
  	const struct tls_cipher_suite *suite;
  
  	suite = tls_get_cipher_suite(conn->rl.cipher_suite);
  	if (suite == NULL)
  		keyx = TLS_KEY_X_NULL;
  	else
  		keyx = suite->key_exchange;
  
  	pos = *msgpos;
  
  	wpa_printf(MSG_DEBUG, "TLSv1: Send ClientKeyExchange");
  
  	rhdr = pos;
  	pos += TLS_RECORD_HEADER_LEN;
  
  	/* opaque fragment[TLSPlaintext.length] */
  
  	/* Handshake */
  	hs_start = pos;
  	/* HandshakeType msg_type */
  	*pos++ = TLS_HANDSHAKE_TYPE_CLIENT_KEY_EXCHANGE;
  	/* uint24 length (to be filled) */
  	hs_length = pos;
  	pos += 3;
  	/* body - ClientKeyExchange */
  	if (keyx == TLS_KEY_X_DH_anon || keyx == TLS_KEY_X_DHE_RSA) {
  		if (tlsv1_key_x_dh(conn, &pos, end) < 0)
  			return -1;
  	} else {
  		if (tlsv1_key_x_rsa(conn, &pos, end) < 0)
  			return -1;
  	}
  
  	WPA_PUT_BE24(hs_length, pos - hs_length - 3);
  
  	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
  			      rhdr, end - rhdr, hs_start, pos - hs_start,
  			      &rlen) < 0) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  	pos = rhdr + rlen;
  	tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
  
  	*msgpos = pos;
  
  	return 0;
  }
  
  
  static int tls_write_client_certificate_verify(struct tlsv1_client *conn,
  					       u8 **msgpos, u8 *end)
  {
  	u8 *pos, *rhdr, *hs_start, *hs_length, *signed_start;
  	size_t rlen, hlen, clen;
  	u8 hash[100], *hpos;
  
  	pos = *msgpos;
  
  	wpa_printf(MSG_DEBUG, "TLSv1: Send CertificateVerify");
  	rhdr = pos;
  	pos += TLS_RECORD_HEADER_LEN;
  
  	/* Handshake */
  	hs_start = pos;
  	/* HandshakeType msg_type */
  	*pos++ = TLS_HANDSHAKE_TYPE_CERTIFICATE_VERIFY;
  	/* uint24 length (to be filled) */
  	hs_length = pos;
  	pos += 3;
  
  	/*
  	 * RFC 2246: 7.4.3 and 7.4.8:
  	 * Signature signature
  	 *
  	 * RSA:
  	 * digitally-signed struct {
  	 *     opaque md5_hash[16];
  	 *     opaque sha_hash[20];
  	 * };
  	 *
  	 * DSA:
  	 * digitally-signed struct {
  	 *     opaque sha_hash[20];
  	 * };
  	 *
  	 * The hash values are calculated over all handshake messages sent or
  	 * received starting at ClientHello up to, but not including, this
  	 * CertificateVerify message, including the type and length fields of
  	 * the handshake messages.
  	 */
  
  	hpos = hash;
  
  #ifdef CONFIG_TLSV12
  	if (conn->rl.tls_version == TLS_VERSION_1_2) {
  		hlen = SHA256_MAC_LEN;
  		if (conn->verify.sha256_cert == NULL ||
  		    crypto_hash_finish(conn->verify.sha256_cert, hpos, &hlen) <
  		    0) {
  			conn->verify.sha256_cert = NULL;
  			tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  				  TLS_ALERT_INTERNAL_ERROR);
  			return -1;
  		}
  		conn->verify.sha256_cert = NULL;
  
  		/*
  		 * RFC 3447, A.2.4 RSASSA-PKCS1-v1_5
  		 *
  		 * DigestInfo ::= SEQUENCE {
  		 *   digestAlgorithm DigestAlgorithm,
  		 *   digest OCTET STRING
  		 * }
  		 *
  		 * SHA-256 OID: sha256WithRSAEncryption ::= {pkcs-1 11}
  		 *
  		 * DER encoded DigestInfo for SHA256 per RFC 3447:
  		 * 30 31 30 0d 06 09 60 86 48 01 65 03 04 02 01 05 00 04 20 ||
  		 * H
  		 */
  		os_memmove(hash + 19, hash, hlen);
  		hlen += 19;
  		os_memcpy(hash, "\x30\x31\x30\x0d\x06\x09\x60\x86\x48\x01\x65"
  			  "\x03\x04\x02\x01\x05\x00\x04\x20", 19);
  	} else {
  #endif /* CONFIG_TLSV12 */
  
  	hlen = MD5_MAC_LEN;
  	if (conn->verify.md5_cert == NULL ||
  	    crypto_hash_finish(conn->verify.md5_cert, hpos, &hlen) < 0) {
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		conn->verify.md5_cert = NULL;
  		crypto_hash_finish(conn->verify.sha1_cert, NULL, NULL);
  		conn->verify.sha1_cert = NULL;
  		return -1;
  	}
  	hpos += MD5_MAC_LEN;
  
  	conn->verify.md5_cert = NULL;
  	hlen = SHA1_MAC_LEN;
  	if (conn->verify.sha1_cert == NULL ||
  	    crypto_hash_finish(conn->verify.sha1_cert, hpos, &hlen) < 0) {
  		conn->verify.sha1_cert = NULL;
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  	conn->verify.sha1_cert = NULL;
  
  	hlen += MD5_MAC_LEN;
  
  #ifdef CONFIG_TLSV12
  	}
  #endif /* CONFIG_TLSV12 */
  
  	wpa_hexdump(MSG_MSGDUMP, "TLSv1: CertificateVerify hash", hash, hlen);
  
  #ifdef CONFIG_TLSV12
  	if (conn->rl.tls_version >= TLS_VERSION_1_2) {
  		/*
  		 * RFC 5246, 4.7:
  		 * TLS v1.2 adds explicit indication of the used signature and
  		 * hash algorithms.
  		 *
  		 * struct {
  		 *   HashAlgorithm hash;
  		 *   SignatureAlgorithm signature;
  		 * } SignatureAndHashAlgorithm;
  		 */
  		*pos++ = TLS_HASH_ALG_SHA256;
  		*pos++ = TLS_SIGN_ALG_RSA;
  	}
  #endif /* CONFIG_TLSV12 */
  
  	/*
  	 * RFC 2246, 4.7:
  	 * In digital signing, one-way hash functions are used as input for a
  	 * signing algorithm. A digitally-signed element is encoded as an
  	 * opaque vector <0..2^16-1>, where the length is specified by the
  	 * signing algorithm and key.
  	 *
  	 * In RSA signing, a 36-byte structure of two hashes (one SHA and one
  	 * MD5) is signed (encrypted with the private key). It is encoded with
  	 * PKCS #1 block type 0 or type 1 as described in [PKCS1].
  	 */
  	signed_start = pos; /* length to be filled */
  	pos += 2;
  	clen = end - pos;
  	if (conn->cred == NULL ||
  	    crypto_private_key_sign_pkcs1(conn->cred->key, hash, hlen,
  					  pos, &clen) < 0) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to sign hash (PKCS #1)");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  	WPA_PUT_BE16(signed_start, clen);
  
  	pos += clen;
  
  	WPA_PUT_BE24(hs_length, pos - hs_length - 3);
  
  	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
  			      rhdr, end - rhdr, hs_start, pos - hs_start,
  			      &rlen) < 0) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate a record");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  	pos = rhdr + rlen;
  
  	tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
  
  	*msgpos = pos;
  
  	return 0;
  }
  
  
  static int tls_write_client_change_cipher_spec(struct tlsv1_client *conn,
  					       u8 **msgpos, u8 *end)
  {
  	size_t rlen;
  	u8 payload[1];
  
  	wpa_printf(MSG_DEBUG, "TLSv1: Send ChangeCipherSpec");
  
  	payload[0] = TLS_CHANGE_CIPHER_SPEC;
  
  	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_CHANGE_CIPHER_SPEC,
  			      *msgpos, end - *msgpos, payload, sizeof(payload),
  			      &rlen) < 0) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  
  	if (tlsv1_record_change_write_cipher(&conn->rl) < 0) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to set write cipher for "
  			   "record layer");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  
  	*msgpos += rlen;
  
  	return 0;
  }
  
  
  static int tls_write_client_finished(struct tlsv1_client *conn,
  				     u8 **msgpos, u8 *end)
  {
  	u8 *pos, *hs_start;
  	size_t rlen, hlen;
  	u8 verify_data[1 + 3 + TLS_VERIFY_DATA_LEN];
  	u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN];
  
  	wpa_printf(MSG_DEBUG, "TLSv1: Send Finished");
  
  	/* Encrypted Handshake Message: Finished */
  
  #ifdef CONFIG_TLSV12
  	if (conn->rl.tls_version >= TLS_VERSION_1_2) {
  		hlen = SHA256_MAC_LEN;
  		if (conn->verify.sha256_client == NULL ||
  		    crypto_hash_finish(conn->verify.sha256_client, hash, &hlen)
  		    < 0) {
  			tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  				  TLS_ALERT_INTERNAL_ERROR);
  			conn->verify.sha256_client = NULL;
  			return -1;
  		}
  		conn->verify.sha256_client = NULL;
  	} else {
  #endif /* CONFIG_TLSV12 */
  
  	hlen = MD5_MAC_LEN;
  	if (conn->verify.md5_client == NULL ||
  	    crypto_hash_finish(conn->verify.md5_client, hash, &hlen) < 0) {
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		conn->verify.md5_client = NULL;
  		crypto_hash_finish(conn->verify.sha1_client, NULL, NULL);
  		conn->verify.sha1_client = NULL;
  		return -1;
  	}
  	conn->verify.md5_client = NULL;
  	hlen = SHA1_MAC_LEN;
  	if (conn->verify.sha1_client == NULL ||
  	    crypto_hash_finish(conn->verify.sha1_client, hash + MD5_MAC_LEN,
  			       &hlen) < 0) {
  		conn->verify.sha1_client = NULL;
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  	conn->verify.sha1_client = NULL;
  	hlen = MD5_MAC_LEN + SHA1_MAC_LEN;
  
  #ifdef CONFIG_TLSV12
  	}
  #endif /* CONFIG_TLSV12 */
  
  	if (tls_prf(conn->rl.tls_version,
  		    conn->master_secret, TLS_MASTER_SECRET_LEN,
  		    "client finished", hash, hlen,
  		    verify_data + 1 + 3, TLS_VERIFY_DATA_LEN)) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to generate verify_data");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  	wpa_hexdump_key(MSG_DEBUG, "TLSv1: verify_data (client)",
  			verify_data + 1 + 3, TLS_VERIFY_DATA_LEN);
  
  	/* Handshake */
  	pos = hs_start = verify_data;
  	/* HandshakeType msg_type */
  	*pos++ = TLS_HANDSHAKE_TYPE_FINISHED;
  	/* uint24 length */
  	WPA_PUT_BE24(pos, TLS_VERIFY_DATA_LEN);
  	pos += 3;
  	pos += TLS_VERIFY_DATA_LEN; /* verify_data already in place */
  	tls_verify_hash_add(&conn->verify, hs_start, pos - hs_start);
  
  	if (tlsv1_record_send(&conn->rl, TLS_CONTENT_TYPE_HANDSHAKE,
  			      *msgpos, end - *msgpos, hs_start, pos - hs_start,
  			      &rlen) < 0) {
  		wpa_printf(MSG_DEBUG, "TLSv1: Failed to create a record");
  		tls_alert(conn, TLS_ALERT_LEVEL_FATAL,
  			  TLS_ALERT_INTERNAL_ERROR);
  		return -1;
  	}
  
  	*msgpos += rlen;
  
  	return 0;
  }
  
  
  static u8 * tls_send_client_key_exchange(struct tlsv1_client *conn,
  					 size_t *out_len)
  {
  	u8 *msg, *end, *pos;
  	size_t msglen;
  
  	*out_len = 0;
  
  	msglen = 2000;
  	if (conn->certificate_requested)
  		msglen += tls_client_cert_chain_der_len(conn);
  
  	msg = os_malloc(msglen);
  	if (msg == NULL)
  		return NULL;
  
  	pos = msg;
  	end = msg + msglen;
  
  	if (conn->certificate_requested) {
  		if (tls_write_client_certificate(conn, &pos, end) < 0) {
  			os_free(msg);
  			return NULL;
  		}
  	}
  
  	if (tls_write_client_key_exchange(conn, &pos, end) < 0 ||
  	    (conn->certificate_requested && conn->cred && conn->cred->key &&
  	     tls_write_client_certificate_verify(conn, &pos, end) < 0) ||
  	    tls_write_client_change_cipher_spec(conn, &pos, end) < 0 ||
  	    tls_write_client_finished(conn, &pos, end) < 0) {
  		os_free(msg);
  		return NULL;
  	}
  
  	*out_len = pos - msg;
  
  	conn->state = SERVER_CHANGE_CIPHER_SPEC;
  
  	return msg;
  }
  
  
  static u8 * tls_send_change_cipher_spec(struct tlsv1_client *conn,
  					size_t *out_len)
  {
  	u8 *msg, *end, *pos;
  
  	*out_len = 0;
  
  	msg = os_malloc(1000);
  	if (msg == NULL)
  		return NULL;
  
  	pos = msg;
  	end = msg + 1000;
  
  	if (tls_write_client_change_cipher_spec(conn, &pos, end) < 0 ||
  	    tls_write_client_finished(conn, &pos, end) < 0) {
  		os_free(msg);
  		return NULL;
  	}
  
  	*out_len = pos - msg;
  
  	wpa_printf(MSG_DEBUG, "TLSv1: Session resumption completed "
  		   "successfully");
  	conn->state = ESTABLISHED;
  
  	return msg;
  }
  
  
  u8 * tlsv1_client_handshake_write(struct tlsv1_client *conn, size_t *out_len,
  				  int no_appl_data)
  {
  	switch (conn->state) {
  	case CLIENT_KEY_EXCHANGE:
  		return tls_send_client_key_exchange(conn, out_len);
  	case CHANGE_CIPHER_SPEC:
  		return tls_send_change_cipher_spec(conn, out_len);
  	case ACK_FINISHED:
  		wpa_printf(MSG_DEBUG, "TLSv1: Handshake completed "
  			   "successfully");
  		conn->state = ESTABLISHED;
  		*out_len = 0;
  		if (no_appl_data) {
  			/* Need to return something to get final TLS ACK. */
  			return os_malloc(1);
  		}
  		return NULL;
  	default:
  		wpa_printf(MSG_DEBUG, "TLSv1: Unexpected state %d while "
  			   "generating reply", conn->state);
  		return NULL;
  	}
  }
  
  
  u8 * tlsv1_client_send_alert(struct tlsv1_client *conn, u8 level,
  			     u8 description, size_t *out_len)
  {
  	u8 *alert, *pos, *length;
  
  	wpa_printf(MSG_DEBUG, "TLSv1: Send Alert(%d:%d)", level, description);
  	*out_len = 0;
  
  	alert = os_malloc(10);
  	if (alert == NULL)
  		return NULL;
  
  	pos = alert;
  
  	/* TLSPlaintext */
  	/* ContentType type */
  	*pos++ = TLS_CONTENT_TYPE_ALERT;
  	/* ProtocolVersion version */
  	WPA_PUT_BE16(pos, conn->rl.tls_version ? conn->rl.tls_version :
  		     TLS_VERSION);
  	pos += 2;
  	/* uint16 length (to be filled) */
  	length = pos;
  	pos += 2;
  	/* opaque fragment[TLSPlaintext.length] */
  
  	/* Alert */
  	/* AlertLevel level */
  	*pos++ = level;
  	/* AlertDescription description */
  	*pos++ = description;
  
  	WPA_PUT_BE16(length, pos - length - 2);
  	*out_len = pos - alert;
  
  	return alert;
  }
  