/*
* TLSv1 server - read 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 "x509v3.h"
#include "tlsv1_common.h"
#include "tlsv1_record.h"
#include "tlsv1_server.h"
#include "tlsv1_server_i.h"
static int tls_process_client_key_exchange(struct tlsv1_server *conn, u8 ct,
const u8 *in_data, size_t *in_len);
static int tls_process_change_cipher_spec(struct tlsv1_server *conn,
u8 ct, const u8 *in_data,
size_t *in_len);
static int testing_cipher_suite_filter(struct tlsv1_server *conn, u16 suite)
{
#ifdef CONFIG_TESTING_OPTIONS
if ((conn->test_flags &
(TLS_BREAK_SRV_KEY_X_HASH | TLS_BREAK_SRV_KEY_X_SIGNATURE |
TLS_DHE_PRIME_511B | TLS_DHE_PRIME_767B | TLS_DHE_PRIME_15 |
TLS_DHE_PRIME_58B | TLS_DHE_NON_PRIME)) &&
suite != TLS_DHE_RSA_WITH_AES_256_CBC_SHA256 &&
suite != TLS_DHE_RSA_WITH_AES_256_CBC_SHA &&
suite != TLS_DHE_RSA_WITH_AES_128_CBC_SHA256 &&
suite != TLS_DHE_RSA_WITH_AES_128_CBC_SHA &&
suite != TLS_DHE_RSA_WITH_3DES_EDE_CBC_SHA)
return 1;
#endif /* CONFIG_TESTING_OPTIONS */
return 0;
}
static void tls_process_status_request_item(struct tlsv1_server *conn,
const u8 *req, size_t req_len)
{
const u8 *pos, *end;
u8 status_type;
pos = req;
end = req + req_len;
/*
* RFC 6961, 2.2:
* struct {
* CertificateStatusType status_type;
* uint16 request_length;
* select (status_type) {
* case ocsp: OCSPStatusRequest;
* case ocsp_multi: OCSPStatusRequest;
* } request;
* } CertificateStatusRequestItemV2;
*
* enum { ocsp(1), ocsp_multi(2), (255) } CertificateStatusType;
*/
if (end - pos < 1)
return; /* Truncated data */
status_type = *pos++;
wpa_printf(MSG_DEBUG, "TLSv1: CertificateStatusType %u", status_type);
if (status_type != 1 && status_type != 2)
return; /* Unsupported status type */
/*
* For now, only OCSP stapling is supported, so ignore the specific
* request, if any.
*/
wpa_hexdump(MSG_DEBUG, "TLSv1: OCSPStatusRequest", pos, end - pos);
if (status_type == 2)
conn->status_request_multi = 1;
}
static void tls_process_status_request_v2(struct tlsv1_server *conn,
const u8 *ext, size_t ext_len)
{
const u8 *pos, *end;
conn->status_request_v2 = 1;
pos = ext;
end = ext + ext_len;
/*
* RFC 6961, 2.2:
* struct {
* CertificateStatusRequestItemV2
* certificate_status_req_list<1..2^16-1>;
* } CertificateStatusRequestListV2;
*/
while (end - pos >= 2) {
u16 len;
len = WPA_GET_BE16(pos);
pos += 2;
if (len > end - pos)
break; /* Truncated data */
tls_process_status_request_item(conn, pos, len);
pos += len;
}
}
static int tls_process_client_hello(struct tlsv1_server *conn, u8 ct,
const u8 *in_data, size_t *in_len)
{
const u8 *pos, *end, *c;
size_t left, len, i, j;
u16 cipher_suite;
u16 num_suites;
int compr_null_found;
u16 ext_type, ext_len;
if (ct != TLS_CONTENT_TYPE_HANDSHAKE) {
tlsv1_server_log(conn, "Expected Handshake; received content type 0x%x",
ct);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
pos = in_data;
left = *in_len;
if (left < 4)
goto decode_error;
/* HandshakeType msg_type */
if (*pos != TLS_HANDSHAKE_TYPE_CLIENT_HELLO) {
tlsv1_server_log(conn, "Received unexpected handshake message %d (expected ClientHello)",
*pos);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
tlsv1_server_log(conn, "Received ClientHello");
pos++;
/* uint24 length */
len = WPA_GET_BE24(pos);
pos += 3;
left -= 4;
if (len > left)
goto decode_error;
/* body - ClientHello */
wpa_hexdump(MSG_MSGDUMP, "TLSv1: ClientHello", pos, len);
end = pos + len;
/* ProtocolVersion client_version */
if (end - pos < 2)
goto decode_error;
conn->client_version = WPA_GET_BE16(pos);
tlsv1_server_log(conn, "Client version %d.%d",
conn->client_version >> 8,
conn->client_version & 0xff);
if (conn->client_version < TLS_VERSION_1) {
tlsv1_server_log(conn, "Unexpected protocol version in ClientHello %u.%u",
conn->client_version >> 8,
conn->client_version & 0xff);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_PROTOCOL_VERSION);
return -1;
}
pos += 2;
if (TLS_VERSION == TLS_VERSION_1)
conn->rl.tls_version = TLS_VERSION_1;
#ifdef CONFIG_TLSV12
else if (conn->client_version >= TLS_VERSION_1_2)
conn->rl.tls_version = TLS_VERSION_1_2;
#endif /* CONFIG_TLSV12 */
else if (conn->client_version > TLS_VERSION_1_1)
conn->rl.tls_version = TLS_VERSION_1_1;
else
conn->rl.tls_version = conn->client_version;
tlsv1_server_log(conn, "Using TLS v%s",
tls_version_str(conn->rl.tls_version));
/* Random random */
if (end - pos < TLS_RANDOM_LEN)
goto decode_error;
os_memcpy(conn->client_random, pos, TLS_RANDOM_LEN);
pos += TLS_RANDOM_LEN;
wpa_hexdump(MSG_MSGDUMP, "TLSv1: client_random",
conn->client_random, TLS_RANDOM_LEN);
/* SessionID session_id */
if (end - pos < 1)
goto decode_error;
if (end - pos < 1 + *pos || *pos > TLS_SESSION_ID_MAX_LEN)
goto decode_error;
wpa_hexdump(MSG_MSGDUMP, "TLSv1: client session_id", pos + 1, *pos);
pos += 1 + *pos;
/* TODO: add support for session resumption */
/* CipherSuite cipher_suites<2..2^16-1> */
if (end - pos < 2)
goto decode_error;
num_suites = WPA_GET_BE16(pos);
pos += 2;
if (end - pos < num_suites)
goto decode_error;
wpa_hexdump(MSG_MSGDUMP, "TLSv1: client cipher suites",
pos, num_suites);
if (num_suites & 1)
goto decode_error;
num_suites /= 2;
cipher_suite = 0;
for (i = 0; !cipher_suite && i < conn->num_cipher_suites; i++) {
if (testing_cipher_suite_filter(conn, conn->cipher_suites[i]))
continue;
c = pos;
for (j = 0; j < num_suites; j++) {
u16 tmp = WPA_GET_BE16(c);
c += 2;
if (!cipher_suite && tmp == conn->cipher_suites[i]) {
cipher_suite = tmp;
break;
}
}
}
pos += num_suites * 2;
if (!cipher_suite) {
tlsv1_server_log(conn, "No supported cipher suite available");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_ILLEGAL_PARAMETER);
return -1;
}
if (tlsv1_record_set_cipher_suite(&conn->rl, cipher_suite) < 0) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to set CipherSuite for "
"record layer");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
conn->cipher_suite = cipher_suite;
/* CompressionMethod compression_methods<1..2^8-1> */
if (end - pos < 1)
goto decode_error;
num_suites = *pos++;
if (end - pos < num_suites)
goto decode_error;
wpa_hexdump(MSG_MSGDUMP, "TLSv1: client compression_methods",
pos, num_suites);
compr_null_found = 0;
for (i = 0; i < num_suites; i++) {
if (*pos++ == TLS_COMPRESSION_NULL)
compr_null_found = 1;
}
if (!compr_null_found) {
tlsv1_server_log(conn, "Client does not accept NULL compression");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_ILLEGAL_PARAMETER);
return -1;
}
if (end - pos == 1) {
tlsv1_server_log(conn, "Unexpected extra octet in the end of ClientHello: 0x%02x",
*pos);
goto decode_error;
}
if (end - pos >= 2) {
/* Extension client_hello_extension_list<0..2^16-1> */
ext_len = WPA_GET_BE16(pos);
pos += 2;
tlsv1_server_log(conn, "%u bytes of ClientHello extensions",
ext_len);
if (end - pos != ext_len) {
tlsv1_server_log(conn, "Invalid ClientHello extension list length %u (expected %u)",
ext_len, (unsigned int) (end - pos));
goto decode_error;
}
/*
* struct {
* ExtensionType extension_type (0..65535)
* opaque extension_data<0..2^16-1>
* } Extension;
*/
while (pos < end) {
if (end - pos < 2) {
tlsv1_server_log(conn, "Invalid extension_type field");
goto decode_error;
}
ext_type = WPA_GET_BE16(pos);
pos += 2;
if (end - pos < 2) {
tlsv1_server_log(conn, "Invalid extension_data length field");
goto decode_error;
}
ext_len = WPA_GET_BE16(pos);
pos += 2;
if (end - pos < ext_len) {
tlsv1_server_log(conn, "Invalid extension_data field");
goto decode_error;
}
tlsv1_server_log(conn, "ClientHello Extension type %u",
ext_type);
wpa_hexdump(MSG_MSGDUMP, "TLSv1: ClientHello "
"Extension data", pos, ext_len);
if (ext_type == TLS_EXT_SESSION_TICKET) {
os_free(conn->session_ticket);
conn->session_ticket = os_malloc(ext_len);
if (conn->session_ticket) {
os_memcpy(conn->session_ticket, pos,
ext_len);
conn->session_ticket_len = ext_len;
}
} else if (ext_type == TLS_EXT_STATUS_REQUEST) {
conn->status_request = 1;
} else if (ext_type == TLS_EXT_STATUS_REQUEST_V2) {
tls_process_status_request_v2(conn, pos,
ext_len);
}
pos += ext_len;
}
}
*in_len = end - in_data;
tlsv1_server_log(conn, "ClientHello OK - proceed to ServerHello");
conn->state = SERVER_HELLO;
return 0;
decode_error:
tlsv1_server_log(conn, "Failed to decode ClientHello");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
static int tls_process_certificate(struct tlsv1_server *conn, u8 ct,
const u8 *in_data, size_t *in_len)
{
const u8 *pos, *end;
size_t left, len, list_len, cert_len, idx;
u8 type;
struct x509_certificate *chain = NULL, *last = NULL, *cert;
int reason;
if (ct != TLS_CONTENT_TYPE_HANDSHAKE) {
tlsv1_server_log(conn, "Expected Handshake; received content type 0x%x",
ct);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
pos = in_data;
left = *in_len;
if (left < 4) {
tlsv1_server_log(conn, "Too short Certificate message (len=%lu)",
(unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
type = *pos++;
len = WPA_GET_BE24(pos);
pos += 3;
left -= 4;
if (len > left) {
tlsv1_server_log(conn, "Unexpected Certificate message length (len=%lu != left=%lu)",
(unsigned long) len, (unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
if (type == TLS_HANDSHAKE_TYPE_CLIENT_KEY_EXCHANGE) {
if (conn->verify_peer) {
tlsv1_server_log(conn, "Client did not include Certificate");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
return tls_process_client_key_exchange(conn, ct, in_data,
in_len);
}
if (type != TLS_HANDSHAKE_TYPE_CERTIFICATE) {
tlsv1_server_log(conn, "Received unexpected handshake message %d (expected Certificate/ClientKeyExchange)",
type);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
tlsv1_server_log(conn, "Received Certificate (certificate_list len %lu)",
(unsigned long) len);
/*
* opaque ASN.1Cert<2^24-1>;
*
* struct {
* ASN.1Cert certificate_list<1..2^24-1>;
* } Certificate;
*/
end = pos + len;
if (end - pos < 3) {
tlsv1_server_log(conn, "Too short Certificate (left=%lu)",
(unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
list_len = WPA_GET_BE24(pos);
pos += 3;
if ((size_t) (end - pos) != list_len) {
tlsv1_server_log(conn, "Unexpected certificate_list length (len=%lu left=%lu)",
(unsigned long) list_len,
(unsigned long) (end - pos));
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
idx = 0;
while (pos < end) {
if (end - pos < 3) {
tlsv1_server_log(conn, "Failed to parse certificate_list");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
x509_certificate_chain_free(chain);
return -1;
}
cert_len = WPA_GET_BE24(pos);
pos += 3;
if ((size_t) (end - pos) < cert_len) {
tlsv1_server_log(conn, "Unexpected certificate length (len=%lu left=%lu)",
(unsigned long) cert_len,
(unsigned long) (end - pos));
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
x509_certificate_chain_free(chain);
return -1;
}
tlsv1_server_log(conn, "Certificate %lu (len %lu)",
(unsigned long) idx, (unsigned long) cert_len);
if (idx == 0) {
crypto_public_key_free(conn->client_rsa_key);
if (tls_parse_cert(pos, cert_len,
&conn->client_rsa_key)) {
tlsv1_server_log(conn, "Failed to parse the certificate");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_BAD_CERTIFICATE);
x509_certificate_chain_free(chain);
return -1;
}
}
cert = x509_certificate_parse(pos, cert_len);
if (cert == NULL) {
tlsv1_server_log(conn, "Failed to parse the certificate");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_BAD_CERTIFICATE);
x509_certificate_chain_free(chain);
return -1;
}
if (last == NULL)
chain = cert;
else
last->next = cert;
last = cert;
idx++;
pos += cert_len;
}
if (x509_certificate_chain_validate(conn->cred->trusted_certs, chain,
&reason, 0) < 0) {
int tls_reason;
tlsv1_server_log(conn, "Server certificate chain validation failed (reason=%d)",
reason);
switch (reason) {
case X509_VALIDATE_BAD_CERTIFICATE:
tls_reason = TLS_ALERT_BAD_CERTIFICATE;
break;
case X509_VALIDATE_UNSUPPORTED_CERTIFICATE:
tls_reason = TLS_ALERT_UNSUPPORTED_CERTIFICATE;
break;
case X509_VALIDATE_CERTIFICATE_REVOKED:
tls_reason = TLS_ALERT_CERTIFICATE_REVOKED;
break;
case X509_VALIDATE_CERTIFICATE_EXPIRED:
tls_reason = TLS_ALERT_CERTIFICATE_EXPIRED;
break;
case X509_VALIDATE_CERTIFICATE_UNKNOWN:
tls_reason = TLS_ALERT_CERTIFICATE_UNKNOWN;
break;
case X509_VALIDATE_UNKNOWN_CA:
tls_reason = TLS_ALERT_UNKNOWN_CA;
break;
default:
tls_reason = TLS_ALERT_BAD_CERTIFICATE;
break;
}
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, tls_reason);
x509_certificate_chain_free(chain);
return -1;
}
if (chain && (chain->extensions_present & X509_EXT_EXT_KEY_USAGE) &&
!(chain->ext_key_usage &
(X509_EXT_KEY_USAGE_ANY | X509_EXT_KEY_USAGE_CLIENT_AUTH))) {
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_BAD_CERTIFICATE);
x509_certificate_chain_free(chain);
return -1;
}
x509_certificate_chain_free(chain);
*in_len = end - in_data;
conn->state = CLIENT_KEY_EXCHANGE;
return 0;
}
static int tls_process_client_key_exchange_rsa(
struct tlsv1_server *conn, const u8 *pos, const u8 *end)
{
u8 *out;
size_t outlen, outbuflen;
u16 encr_len;
int res;
int use_random = 0;
if (end - pos < 2) {
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
encr_len = WPA_GET_BE16(pos);
pos += 2;
if (pos + encr_len > end) {
tlsv1_server_log(conn, "Invalid ClientKeyExchange format: encr_len=%u left=%u",
encr_len, (unsigned int) (end - pos));
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
outbuflen = outlen = end - pos;
out = os_malloc(outlen >= TLS_PRE_MASTER_SECRET_LEN ?
outlen : TLS_PRE_MASTER_SECRET_LEN);
if (out == NULL) {
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
/*
* struct {
* ProtocolVersion client_version;
* opaque random[46];
* } PreMasterSecret;
*
* struct {
* public-key-encrypted PreMasterSecret pre_master_secret;
* } EncryptedPreMasterSecret;
*/
/*
* Note: To avoid Bleichenbacher attack, we do not report decryption or
* parsing errors from EncryptedPreMasterSecret processing to the
* client. Instead, a random pre-master secret is used to force the
* handshake to fail.
*/
if (crypto_private_key_decrypt_pkcs1_v15(conn->cred->key,
pos, encr_len,
out, &outlen) < 0) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to decrypt "
"PreMasterSecret (encr_len=%u outlen=%lu)",
encr_len, (unsigned long) outlen);
use_random = 1;
}
if (!use_random && outlen != TLS_PRE_MASTER_SECRET_LEN) {
tlsv1_server_log(conn, "Unexpected PreMasterSecret length %lu",
(unsigned long) outlen);
use_random = 1;
}
if (!use_random && WPA_GET_BE16(out) != conn->client_version) {
tlsv1_server_log(conn, "Client version in ClientKeyExchange does not match with version in ClientHello");
use_random = 1;
}
if (use_random) {
wpa_printf(MSG_DEBUG, "TLSv1: Using random premaster secret "
"to avoid revealing information about private key");
outlen = TLS_PRE_MASTER_SECRET_LEN;
if (os_get_random(out, outlen)) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to get random "
"data");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
os_free(out);
return -1;
}
}
res = tlsv1_server_derive_keys(conn, out, outlen);
/* Clear the pre-master secret since it is not needed anymore */
os_memset(out, 0, outbuflen);
os_free(out);
if (res) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive keys");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
return 0;
}
static int tls_process_client_key_exchange_dh(
struct tlsv1_server *conn, const u8 *pos, const u8 *end)
{
const u8 *dh_yc;
u16 dh_yc_len;
u8 *shared;
size_t shared_len;
int res;
const u8 *dh_p;
size_t dh_p_len;
/*
* struct {
* select (PublicValueEncoding) {
* case implicit: struct { };
* case explicit: opaque dh_Yc<1..2^16-1>;
* } dh_public;
* } ClientDiffieHellmanPublic;
*/
tlsv1_server_log(conn, "ClientDiffieHellmanPublic received");
wpa_hexdump(MSG_MSGDUMP, "TLSv1: ClientDiffieHellmanPublic",
pos, end - pos);
if (end == pos) {
wpa_printf(MSG_DEBUG, "TLSv1: Implicit public value encoding "
"not supported");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
if (end - pos < 3) {
tlsv1_server_log(conn, "Invalid client public value length");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
dh_yc_len = WPA_GET_BE16(pos);
dh_yc = pos + 2;
if (dh_yc_len > end - dh_yc) {
tlsv1_server_log(conn, "Client public value overflow (length %d)",
dh_yc_len);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
wpa_hexdump(MSG_DEBUG, "TLSv1: DH Yc (client's public value)",
dh_yc, dh_yc_len);
if (conn->cred == NULL || conn->cred->dh_p == NULL ||
conn->dh_secret == NULL) {
wpa_printf(MSG_DEBUG, "TLSv1: No DH parameters available");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
tlsv1_server_get_dh_p(conn, &dh_p, &dh_p_len);
shared_len = dh_p_len;
shared = os_malloc(shared_len);
if (shared == NULL) {
wpa_printf(MSG_DEBUG, "TLSv1: Could not allocate memory for "
"DH");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
/* shared = Yc^secret mod p */
if (crypto_mod_exp(dh_yc, dh_yc_len, conn->dh_secret,
conn->dh_secret_len, dh_p, dh_p_len,
shared, &shared_len)) {
os_free(shared);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
wpa_hexdump_key(MSG_DEBUG, "TLSv1: Shared secret from DH key exchange",
shared, shared_len);
os_memset(conn->dh_secret, 0, conn->dh_secret_len);
os_free(conn->dh_secret);
conn->dh_secret = NULL;
res = tlsv1_server_derive_keys(conn, shared, shared_len);
/* Clear the pre-master secret since it is not needed anymore */
os_memset(shared, 0, shared_len);
os_free(shared);
if (res) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive keys");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
return 0;
}
static int tls_process_client_key_exchange(struct tlsv1_server *conn, u8 ct,
const u8 *in_data, size_t *in_len)
{
const u8 *pos, *end;
size_t left, len;
u8 type;
tls_key_exchange keyx;
const struct tls_cipher_suite *suite;
if (ct != TLS_CONTENT_TYPE_HANDSHAKE) {
tlsv1_server_log(conn, "Expected Handshake; received content type 0x%x",
ct);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
pos = in_data;
left = *in_len;
if (left < 4) {
tlsv1_server_log(conn, "Too short ClientKeyExchange (Left=%lu)",
(unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
type = *pos++;
len = WPA_GET_BE24(pos);
pos += 3;
left -= 4;
if (len > left) {
tlsv1_server_log(conn, "Mismatch in ClientKeyExchange length (len=%lu != left=%lu)",
(unsigned long) len, (unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
end = pos + len;
if (type != TLS_HANDSHAKE_TYPE_CLIENT_KEY_EXCHANGE) {
tlsv1_server_log(conn, "Received unexpected handshake message %d (expected ClientKeyExchange)",
type);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
tlsv1_server_log(conn, "Received ClientKeyExchange");
wpa_hexdump(MSG_DEBUG, "TLSv1: ClientKeyExchange", pos, len);
suite = tls_get_cipher_suite(conn->rl.cipher_suite);
if (suite == NULL)
keyx = TLS_KEY_X_NULL;
else
keyx = suite->key_exchange;
if ((keyx == TLS_KEY_X_DH_anon || keyx == TLS_KEY_X_DHE_RSA) &&
tls_process_client_key_exchange_dh(conn, pos, end) < 0)
return -1;
if (keyx != TLS_KEY_X_DH_anon && keyx != TLS_KEY_X_DHE_RSA &&
tls_process_client_key_exchange_rsa(conn, pos, end) < 0)
return -1;
*in_len = end - in_data;
conn->state = CERTIFICATE_VERIFY;
return 0;
}
static int tls_process_certificate_verify(struct tlsv1_server *conn, u8 ct,
const u8 *in_data, size_t *in_len)
{
const u8 *pos, *end;
size_t left, len;
u8 type;
size_t hlen;
u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN], *hpos;
u8 alert;
if (ct == TLS_CONTENT_TYPE_CHANGE_CIPHER_SPEC) {
if (conn->verify_peer) {
tlsv1_server_log(conn, "Client did not include CertificateVerify");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
return tls_process_change_cipher_spec(conn, ct, in_data,
in_len);
}
if (ct != TLS_CONTENT_TYPE_HANDSHAKE) {
tlsv1_server_log(conn, "Expected Handshake; received content type 0x%x",
ct);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
pos = in_data;
left = *in_len;
if (left < 4) {
tlsv1_server_log(conn, "Too short CertificateVerify message (len=%lu)",
(unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
type = *pos++;
len = WPA_GET_BE24(pos);
pos += 3;
left -= 4;
if (len > left) {
tlsv1_server_log(conn, "Unexpected CertificateVerify message length (len=%lu != left=%lu)",
(unsigned long) len, (unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
end = pos + len;
if (type != TLS_HANDSHAKE_TYPE_CERTIFICATE_VERIFY) {
tlsv1_server_log(conn, "Received unexpected handshake message %d (expected CertificateVerify)",
type);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
tlsv1_server_log(conn, "Received CertificateVerify");
/*
* struct {
* Signature signature;
* } CertificateVerify;
*/
hpos = hash;
#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;
*/
if (end - pos < 2) {
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
if (pos[0] != TLS_HASH_ALG_SHA256 ||
pos[1] != TLS_SIGN_ALG_RSA) {
wpa_printf(MSG_DEBUG, "TLSv1.2: Unsupported hash(%u)/"
"signature(%u) algorithm",
pos[0], pos[1]);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
pos += 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;
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
conn->verify.sha256_cert = NULL;
} else {
#endif /* CONFIG_TLSV12 */
hlen = MD5_MAC_LEN;
if (conn->verify.md5_cert == NULL ||
crypto_hash_finish(conn->verify.md5_cert, hpos, &hlen) < 0) {
tlsv1_server_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;
tlsv1_server_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);
if (tls_verify_signature(conn->rl.tls_version, conn->client_rsa_key,
hash, hlen, pos, end - pos, &alert) < 0) {
tlsv1_server_log(conn, "Invalid Signature in CertificateVerify");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL, alert);
return -1;
}
*in_len = end - in_data;
conn->state = CHANGE_CIPHER_SPEC;
return 0;
}
static int tls_process_change_cipher_spec(struct tlsv1_server *conn,
u8 ct, const u8 *in_data,
size_t *in_len)
{
const u8 *pos;
size_t left;
if (ct != TLS_CONTENT_TYPE_CHANGE_CIPHER_SPEC) {
tlsv1_server_log(conn, "Expected ChangeCipherSpec; received content type 0x%x",
ct);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
pos = in_data;
left = *in_len;
if (left < 1) {
tlsv1_server_log(conn, "Too short ChangeCipherSpec");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
if (*pos != TLS_CHANGE_CIPHER_SPEC) {
tlsv1_server_log(conn, "Expected ChangeCipherSpec; received data 0x%x",
*pos);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
tlsv1_server_log(conn, "Received ChangeCipherSpec");
if (tlsv1_record_change_read_cipher(&conn->rl) < 0) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to change read cipher "
"for record layer");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_INTERNAL_ERROR);
return -1;
}
*in_len = pos + 1 - in_data;
conn->state = CLIENT_FINISHED;
return 0;
}
static int tls_process_client_finished(struct tlsv1_server *conn, u8 ct,
const u8 *in_data, size_t *in_len)
{
const u8 *pos, *end;
size_t left, len, hlen;
u8 verify_data[TLS_VERIFY_DATA_LEN];
u8 hash[MD5_MAC_LEN + SHA1_MAC_LEN];
#ifdef CONFIG_TESTING_OPTIONS
if ((conn->test_flags &
(TLS_BREAK_SRV_KEY_X_HASH | TLS_BREAK_SRV_KEY_X_SIGNATURE)) &&
!conn->test_failure_reported) {
tlsv1_server_log(conn, "TEST-FAILURE: Client Finished received after invalid ServerKeyExchange");
conn->test_failure_reported = 1;
}
if ((conn->test_flags & TLS_DHE_PRIME_15) &&
!conn->test_failure_reported) {
tlsv1_server_log(conn, "TEST-FAILURE: Client Finished received after bogus DHE \"prime\" 15");
conn->test_failure_reported = 1;
}
if ((conn->test_flags & TLS_DHE_PRIME_58B) &&
!conn->test_failure_reported) {
tlsv1_server_log(conn, "TEST-FAILURE: Client Finished received after short 58-bit DHE prime in long container");
conn->test_failure_reported = 1;
}
if ((conn->test_flags & TLS_DHE_PRIME_511B) &&
!conn->test_failure_reported) {
tlsv1_server_log(conn, "TEST-WARNING: Client Finished received after short 511-bit DHE prime (insecure)");
conn->test_failure_reported = 1;
}
if ((conn->test_flags & TLS_DHE_PRIME_767B) &&
!conn->test_failure_reported) {
tlsv1_server_log(conn, "TEST-NOTE: Client Finished received after 767-bit DHE prime (relatively insecure)");
conn->test_failure_reported = 1;
}
if ((conn->test_flags & TLS_DHE_NON_PRIME) &&
!conn->test_failure_reported) {
tlsv1_server_log(conn, "TEST-NOTE: Client Finished received after non-prime claimed as DHE prime");
conn->test_failure_reported = 1;
}
#endif /* CONFIG_TESTING_OPTIONS */
if (ct != TLS_CONTENT_TYPE_HANDSHAKE) {
tlsv1_server_log(conn, "Expected Finished; received content type 0x%x",
ct);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
pos = in_data;
left = *in_len;
if (left < 4) {
tlsv1_server_log(conn, "Too short record (left=%lu) forFinished",
(unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
if (pos[0] != TLS_HANDSHAKE_TYPE_FINISHED) {
wpa_printf(MSG_DEBUG, "TLSv1: Expected Finished; received "
"type 0x%x", pos[0]);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_UNEXPECTED_MESSAGE);
return -1;
}
len = WPA_GET_BE24(pos + 1);
pos += 4;
left -= 4;
if (len > left) {
tlsv1_server_log(conn, "Too short buffer for Finished (len=%lu > left=%lu)",
(unsigned long) len, (unsigned long) left);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
end = pos + len;
if (len != TLS_VERIFY_DATA_LEN) {
tlsv1_server_log(conn, "Unexpected verify_data length in Finished: %lu (expected %d)",
(unsigned long) len, TLS_VERIFY_DATA_LEN);
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
wpa_hexdump(MSG_MSGDUMP, "TLSv1: verify_data in Finished",
pos, TLS_VERIFY_DATA_LEN);
#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) {
tlsv1_server_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) {
tlsv1_server_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;
tlsv1_server_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, TLS_VERIFY_DATA_LEN)) {
wpa_printf(MSG_DEBUG, "TLSv1: Failed to derive verify_data");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECRYPT_ERROR);
return -1;
}
wpa_hexdump_key(MSG_DEBUG, "TLSv1: verify_data (client)",
verify_data, TLS_VERIFY_DATA_LEN);
if (os_memcmp_const(pos, verify_data, TLS_VERIFY_DATA_LEN) != 0) {
tlsv1_server_log(conn, "Mismatch in verify_data");
return -1;
}
tlsv1_server_log(conn, "Received Finished");
*in_len = end - in_data;
if (conn->use_session_ticket) {
/* Abbreviated handshake using session ticket; RFC 4507 */
tlsv1_server_log(conn, "Abbreviated handshake completed successfully");
conn->state = ESTABLISHED;
} else {
/* Full handshake */
conn->state = SERVER_CHANGE_CIPHER_SPEC;
}
return 0;
}
int tlsv1_server_process_handshake(struct tlsv1_server *conn, u8 ct,
const u8 *buf, size_t *len)
{
if (ct == TLS_CONTENT_TYPE_ALERT) {
if (*len < 2) {
tlsv1_server_log(conn, "Alert underflow");
tlsv1_server_alert(conn, TLS_ALERT_LEVEL_FATAL,
TLS_ALERT_DECODE_ERROR);
return -1;
}
tlsv1_server_log(conn, "Received alert %d:%d", buf[0], buf[1]);
*len = 2;
conn->state = FAILED;
return -1;
}
switch (conn->state) {
case CLIENT_HELLO:
if (tls_process_client_hello(conn, ct, buf, len))
return -1;
break;
case CLIENT_CERTIFICATE:
if (tls_process_certificate(conn, ct, buf, len))
return -1;
break;
case CLIENT_KEY_EXCHANGE:
if (tls_process_client_key_exchange(conn, ct, buf, len))
return -1;
break;
case CERTIFICATE_VERIFY:
if (tls_process_certificate_verify(conn, ct, buf, len))
return -1;
break;
case CHANGE_CIPHER_SPEC:
if (tls_process_change_cipher_spec(conn, ct, buf, len))
return -1;
break;
case CLIENT_FINISHED:
if (tls_process_client_finished(conn, ct, buf, len))
return -1;
break;
default:
tlsv1_server_log(conn, "Unexpected state %d while processing received message",
conn->state);
return -1;
}
if (ct == TLS_CONTENT_TYPE_HANDSHAKE)
tls_verify_hash_add(&conn->verify, buf, *len);
return 0;
}