fragattacks/src/crypto/tls_gnutls.c
Jouni Malinen 95de34a10a Remove trailing whitespace
Signed-off-by: Jouni Malinen <j@w1.fi>
2016-12-28 14:31:42 +02:00

1595 lines
39 KiB
C

/*
* SSL/TLS interface functions for GnuTLS
* Copyright (c) 2004-2011, 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 <gnutls/gnutls.h>
#include <gnutls/x509.h>
#ifdef PKCS12_FUNCS
#include <gnutls/pkcs12.h>
#endif /* PKCS12_FUNCS */
#if GNUTLS_VERSION_NUMBER >= 0x030103
#include <gnutls/ocsp.h>
#endif /* 3.1.3 */
#include "common.h"
#include "crypto/crypto.h"
#include "tls.h"
static int tls_gnutls_ref_count = 0;
struct tls_global {
/* Data for session resumption */
void *session_data;
size_t session_data_size;
int server;
int params_set;
gnutls_certificate_credentials_t xcred;
void (*event_cb)(void *ctx, enum tls_event ev,
union tls_event_data *data);
void *cb_ctx;
int cert_in_cb;
char *ocsp_stapling_response;
};
struct tls_connection {
struct tls_global *global;
gnutls_session_t session;
int read_alerts, write_alerts, failed;
u8 *pre_shared_secret;
size_t pre_shared_secret_len;
int established;
int verify_peer;
unsigned int disable_time_checks:1;
struct wpabuf *push_buf;
struct wpabuf *pull_buf;
const u8 *pull_buf_offset;
int params_set;
gnutls_certificate_credentials_t xcred;
char *suffix_match;
char *domain_match;
unsigned int flags;
};
static int tls_connection_verify_peer(gnutls_session_t session);
static void tls_log_func(int level, const char *msg)
{
char *s, *pos;
if (level == 6 || level == 7) {
/* These levels seem to be mostly I/O debug and msg dumps */
return;
}
s = os_strdup(msg);
if (s == NULL)
return;
pos = s;
while (*pos != '\0') {
if (*pos == '\n') {
*pos = '\0';
break;
}
pos++;
}
wpa_printf(level > 3 ? MSG_MSGDUMP : MSG_DEBUG,
"gnutls<%d> %s", level, s);
os_free(s);
}
void * tls_init(const struct tls_config *conf)
{
struct tls_global *global;
if (tls_gnutls_ref_count == 0) {
wpa_printf(MSG_DEBUG,
"GnuTLS: Library version %s (runtime) - %s (build)",
gnutls_check_version(NULL), GNUTLS_VERSION);
}
global = os_zalloc(sizeof(*global));
if (global == NULL)
return NULL;
if (tls_gnutls_ref_count == 0 && gnutls_global_init() < 0) {
os_free(global);
return NULL;
}
tls_gnutls_ref_count++;
gnutls_global_set_log_function(tls_log_func);
if (wpa_debug_show_keys)
gnutls_global_set_log_level(11);
if (conf) {
global->event_cb = conf->event_cb;
global->cb_ctx = conf->cb_ctx;
global->cert_in_cb = conf->cert_in_cb;
}
return global;
}
void tls_deinit(void *ssl_ctx)
{
struct tls_global *global = ssl_ctx;
if (global) {
if (global->params_set)
gnutls_certificate_free_credentials(global->xcred);
os_free(global->session_data);
os_free(global->ocsp_stapling_response);
os_free(global);
}
tls_gnutls_ref_count--;
if (tls_gnutls_ref_count == 0)
gnutls_global_deinit();
}
int tls_get_errors(void *ssl_ctx)
{
return 0;
}
static ssize_t tls_pull_func(gnutls_transport_ptr_t ptr, void *buf,
size_t len)
{
struct tls_connection *conn = (struct tls_connection *) ptr;
const u8 *end;
if (conn->pull_buf == NULL) {
errno = EWOULDBLOCK;
return -1;
}
end = wpabuf_head_u8(conn->pull_buf) + wpabuf_len(conn->pull_buf);
if ((size_t) (end - conn->pull_buf_offset) < len)
len = end - conn->pull_buf_offset;
os_memcpy(buf, conn->pull_buf_offset, len);
conn->pull_buf_offset += len;
if (conn->pull_buf_offset == end) {
wpa_printf(MSG_DEBUG, "%s - pull_buf consumed", __func__);
wpabuf_free(conn->pull_buf);
conn->pull_buf = NULL;
conn->pull_buf_offset = NULL;
} else {
wpa_printf(MSG_DEBUG, "%s - %lu bytes remaining in pull_buf",
__func__,
(unsigned long) (end - conn->pull_buf_offset));
}
return len;
}
static ssize_t tls_push_func(gnutls_transport_ptr_t ptr, const void *buf,
size_t len)
{
struct tls_connection *conn = (struct tls_connection *) ptr;
if (wpabuf_resize(&conn->push_buf, len) < 0) {
errno = ENOMEM;
return -1;
}
wpabuf_put_data(conn->push_buf, buf, len);
return len;
}
static int tls_gnutls_init_session(struct tls_global *global,
struct tls_connection *conn)
{
const char *err;
int ret;
ret = gnutls_init(&conn->session,
global->server ? GNUTLS_SERVER : GNUTLS_CLIENT);
if (ret < 0) {
wpa_printf(MSG_INFO, "TLS: Failed to initialize new TLS "
"connection: %s", gnutls_strerror(ret));
return -1;
}
ret = gnutls_set_default_priority(conn->session);
if (ret < 0)
goto fail;
ret = gnutls_priority_set_direct(conn->session, "NORMAL:-VERS-SSL3.0",
&err);
if (ret < 0) {
wpa_printf(MSG_ERROR, "GnuTLS: Priority string failure at "
"'%s'", err);
goto fail;
}
gnutls_transport_set_pull_function(conn->session, tls_pull_func);
gnutls_transport_set_push_function(conn->session, tls_push_func);
gnutls_transport_set_ptr(conn->session, (gnutls_transport_ptr_t) conn);
gnutls_session_set_ptr(conn->session, conn);
return 0;
fail:
wpa_printf(MSG_INFO, "TLS: Failed to setup new TLS connection: %s",
gnutls_strerror(ret));
gnutls_deinit(conn->session);
return -1;
}
struct tls_connection * tls_connection_init(void *ssl_ctx)
{
struct tls_global *global = ssl_ctx;
struct tls_connection *conn;
int ret;
conn = os_zalloc(sizeof(*conn));
if (conn == NULL)
return NULL;
conn->global = global;
if (tls_gnutls_init_session(global, conn)) {
os_free(conn);
return NULL;
}
if (global->params_set) {
ret = gnutls_credentials_set(conn->session,
GNUTLS_CRD_CERTIFICATE,
global->xcred);
if (ret < 0) {
wpa_printf(MSG_INFO, "Failed to configure "
"credentials: %s", gnutls_strerror(ret));
os_free(conn);
return NULL;
}
}
if (gnutls_certificate_allocate_credentials(&conn->xcred)) {
os_free(conn);
return NULL;
}
return conn;
}
void tls_connection_deinit(void *ssl_ctx, struct tls_connection *conn)
{
if (conn == NULL)
return;
gnutls_certificate_free_credentials(conn->xcred);
gnutls_deinit(conn->session);
os_free(conn->pre_shared_secret);
wpabuf_free(conn->push_buf);
wpabuf_free(conn->pull_buf);
os_free(conn->suffix_match);
os_free(conn->domain_match);
os_free(conn);
}
int tls_connection_established(void *ssl_ctx, struct tls_connection *conn)
{
return conn ? conn->established : 0;
}
int tls_connection_shutdown(void *ssl_ctx, struct tls_connection *conn)
{
struct tls_global *global = ssl_ctx;
int ret;
if (conn == NULL)
return -1;
/* Shutdown previous TLS connection without notifying the peer
* because the connection was already terminated in practice
* and "close notify" shutdown alert would confuse AS. */
gnutls_bye(conn->session, GNUTLS_SHUT_RDWR);
wpabuf_free(conn->push_buf);
conn->push_buf = NULL;
conn->established = 0;
gnutls_deinit(conn->session);
if (tls_gnutls_init_session(global, conn)) {
wpa_printf(MSG_INFO, "GnuTLS: Failed to preparare new session "
"for session resumption use");
return -1;
}
ret = gnutls_credentials_set(conn->session, GNUTLS_CRD_CERTIFICATE,
conn->params_set ? conn->xcred :
global->xcred);
if (ret < 0) {
wpa_printf(MSG_INFO, "GnuTLS: Failed to configure credentials "
"for session resumption: %s", gnutls_strerror(ret));
return -1;
}
if (global->session_data) {
ret = gnutls_session_set_data(conn->session,
global->session_data,
global->session_data_size);
if (ret < 0) {
wpa_printf(MSG_INFO, "GnuTLS: Failed to set session "
"data: %s", gnutls_strerror(ret));
return -1;
}
}
return 0;
}
int tls_connection_set_params(void *tls_ctx, struct tls_connection *conn,
const struct tls_connection_params *params)
{
int ret;
if (conn == NULL || params == NULL)
return -1;
if (params->flags & TLS_CONN_REQUIRE_OCSP_ALL) {
wpa_printf(MSG_INFO,
"GnuTLS: ocsp=3 not supported");
return -1;
}
if (params->flags & TLS_CONN_EXT_CERT_CHECK) {
wpa_printf(MSG_INFO,
"GnuTLS: tls_ext_cert_check=1 not supported");
return -1;
}
if (params->subject_match) {
wpa_printf(MSG_INFO, "GnuTLS: subject_match not supported");
return -1;
}
if (params->altsubject_match) {
wpa_printf(MSG_INFO, "GnuTLS: altsubject_match not supported");
return -1;
}
os_free(conn->suffix_match);
conn->suffix_match = NULL;
if (params->suffix_match) {
conn->suffix_match = os_strdup(params->suffix_match);
if (conn->suffix_match == NULL)
return -1;
}
#if GNUTLS_VERSION_NUMBER >= 0x030300
os_free(conn->domain_match);
conn->domain_match = NULL;
if (params->domain_match) {
conn->domain_match = os_strdup(params->domain_match);
if (conn->domain_match == NULL)
return -1;
}
#else /* < 3.3.0 */
if (params->domain_match) {
wpa_printf(MSG_INFO, "GnuTLS: domain_match not supported");
return -1;
}
#endif /* >= 3.3.0 */
conn->flags = params->flags;
if (params->openssl_ciphers) {
wpa_printf(MSG_INFO, "GnuTLS: openssl_ciphers not supported");
return -1;
}
/* TODO: gnutls_certificate_set_verify_flags(xcred, flags);
* to force peer validation(?) */
if (params->ca_cert) {
wpa_printf(MSG_DEBUG, "GnuTLS: Try to parse %s in DER format",
params->ca_cert);
ret = gnutls_certificate_set_x509_trust_file(
conn->xcred, params->ca_cert, GNUTLS_X509_FMT_DER);
if (ret < 0) {
wpa_printf(MSG_DEBUG,
"GnuTLS: Failed to read CA cert '%s' in DER format (%s) - try in PEM format",
params->ca_cert,
gnutls_strerror(ret));
ret = gnutls_certificate_set_x509_trust_file(
conn->xcred, params->ca_cert,
GNUTLS_X509_FMT_PEM);
if (ret < 0) {
wpa_printf(MSG_DEBUG,
"Failed to read CA cert '%s' in PEM format: %s",
params->ca_cert,
gnutls_strerror(ret));
return -1;
}
}
} else if (params->ca_cert_blob) {
gnutls_datum_t ca;
ca.data = (unsigned char *) params->ca_cert_blob;
ca.size = params->ca_cert_blob_len;
ret = gnutls_certificate_set_x509_trust_mem(
conn->xcred, &ca, GNUTLS_X509_FMT_DER);
if (ret < 0) {
wpa_printf(MSG_DEBUG,
"Failed to parse CA cert in DER format: %s",
gnutls_strerror(ret));
ret = gnutls_certificate_set_x509_trust_mem(
conn->xcred, &ca, GNUTLS_X509_FMT_PEM);
if (ret < 0) {
wpa_printf(MSG_DEBUG,
"Failed to parse CA cert in PEM format: %s",
gnutls_strerror(ret));
return -1;
}
}
} else if (params->ca_path) {
wpa_printf(MSG_INFO, "GnuTLS: ca_path not supported");
return -1;
}
conn->disable_time_checks = 0;
if (params->ca_cert || params->ca_cert_blob) {
conn->verify_peer = 1;
gnutls_certificate_set_verify_function(
conn->xcred, tls_connection_verify_peer);
if (params->flags & TLS_CONN_ALLOW_SIGN_RSA_MD5) {
gnutls_certificate_set_verify_flags(
conn->xcred, GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD5);
}
if (params->flags & TLS_CONN_DISABLE_TIME_CHECKS) {
conn->disable_time_checks = 1;
gnutls_certificate_set_verify_flags(
conn->xcred,
GNUTLS_VERIFY_DISABLE_TIME_CHECKS);
}
}
if (params->client_cert && params->private_key) {
#if GNUTLS_VERSION_NUMBER >= 0x03010b
ret = gnutls_certificate_set_x509_key_file2(
conn->xcred, params->client_cert, params->private_key,
GNUTLS_X509_FMT_DER, params->private_key_passwd, 0);
#else
/* private_key_passwd not (easily) supported here */
ret = gnutls_certificate_set_x509_key_file(
conn->xcred, params->client_cert, params->private_key,
GNUTLS_X509_FMT_DER);
#endif
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read client cert/key "
"in DER format: %s", gnutls_strerror(ret));
#if GNUTLS_VERSION_NUMBER >= 0x03010b
ret = gnutls_certificate_set_x509_key_file2(
conn->xcred, params->client_cert,
params->private_key, GNUTLS_X509_FMT_PEM,
params->private_key_passwd, 0);
#else
ret = gnutls_certificate_set_x509_key_file(
conn->xcred, params->client_cert,
params->private_key, GNUTLS_X509_FMT_PEM);
#endif
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read client "
"cert/key in PEM format: %s",
gnutls_strerror(ret));
return ret;
}
}
} else if (params->private_key) {
int pkcs12_ok = 0;
#ifdef PKCS12_FUNCS
/* Try to load in PKCS#12 format */
ret = gnutls_certificate_set_x509_simple_pkcs12_file(
conn->xcred, params->private_key, GNUTLS_X509_FMT_DER,
params->private_key_passwd);
if (ret != 0) {
wpa_printf(MSG_DEBUG, "Failed to load private_key in "
"PKCS#12 format: %s", gnutls_strerror(ret));
return -1;
} else
pkcs12_ok = 1;
#endif /* PKCS12_FUNCS */
if (!pkcs12_ok) {
wpa_printf(MSG_DEBUG, "GnuTLS: PKCS#12 support not "
"included");
return -1;
}
} else if (params->client_cert_blob && params->private_key_blob) {
gnutls_datum_t cert, key;
cert.data = (unsigned char *) params->client_cert_blob;
cert.size = params->client_cert_blob_len;
key.data = (unsigned char *) params->private_key_blob;
key.size = params->private_key_blob_len;
#if GNUTLS_VERSION_NUMBER >= 0x03010b
ret = gnutls_certificate_set_x509_key_mem2(
conn->xcred, &cert, &key, GNUTLS_X509_FMT_DER,
params->private_key_passwd, 0);
#else
/* private_key_passwd not (easily) supported here */
ret = gnutls_certificate_set_x509_key_mem(
conn->xcred, &cert, &key, GNUTLS_X509_FMT_DER);
#endif
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read client cert/key "
"in DER format: %s", gnutls_strerror(ret));
#if GNUTLS_VERSION_NUMBER >= 0x03010b
ret = gnutls_certificate_set_x509_key_mem2(
conn->xcred, &cert, &key, GNUTLS_X509_FMT_PEM,
params->private_key_passwd, 0);
#else
/* private_key_passwd not (easily) supported here */
ret = gnutls_certificate_set_x509_key_mem(
conn->xcred, &cert, &key, GNUTLS_X509_FMT_PEM);
#endif
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read client "
"cert/key in PEM format: %s",
gnutls_strerror(ret));
return ret;
}
}
} else if (params->private_key_blob) {
#ifdef PKCS12_FUNCS
gnutls_datum_t key;
key.data = (unsigned char *) params->private_key_blob;
key.size = params->private_key_blob_len;
/* Try to load in PKCS#12 format */
ret = gnutls_certificate_set_x509_simple_pkcs12_mem(
conn->xcred, &key, GNUTLS_X509_FMT_DER,
params->private_key_passwd);
if (ret != 0) {
wpa_printf(MSG_DEBUG, "Failed to load private_key in "
"PKCS#12 format: %s", gnutls_strerror(ret));
return -1;
}
#else /* PKCS12_FUNCS */
wpa_printf(MSG_DEBUG, "GnuTLS: PKCS#12 support not included");
return -1;
#endif /* PKCS12_FUNCS */
}
#if GNUTLS_VERSION_NUMBER >= 0x030103
if (params->flags & (TLS_CONN_REQUEST_OCSP | TLS_CONN_REQUIRE_OCSP)) {
ret = gnutls_ocsp_status_request_enable_client(conn->session,
NULL, 0, NULL);
if (ret != GNUTLS_E_SUCCESS) {
wpa_printf(MSG_INFO,
"GnuTLS: Failed to enable OCSP client");
return -1;
}
}
#else /* 3.1.3 */
if (params->flags & TLS_CONN_REQUIRE_OCSP) {
wpa_printf(MSG_INFO,
"GnuTLS: OCSP not supported by this version of GnuTLS");
return -1;
}
#endif /* 3.1.3 */
conn->params_set = 1;
ret = gnutls_credentials_set(conn->session, GNUTLS_CRD_CERTIFICATE,
conn->xcred);
if (ret < 0) {
wpa_printf(MSG_INFO, "Failed to configure credentials: %s",
gnutls_strerror(ret));
}
return ret;
}
#if GNUTLS_VERSION_NUMBER >= 0x030103
static int server_ocsp_status_req(gnutls_session_t session, void *ptr,
gnutls_datum_t *resp)
{
struct tls_global *global = ptr;
char *cached;
size_t len;
if (!global->ocsp_stapling_response) {
wpa_printf(MSG_DEBUG, "GnuTLS: OCSP status callback - no response configured");
return GNUTLS_E_NO_CERTIFICATE_STATUS;
}
cached = os_readfile(global->ocsp_stapling_response, &len);
if (!cached) {
wpa_printf(MSG_DEBUG,
"GnuTLS: OCSP status callback - could not read response file (%s)",
global->ocsp_stapling_response);
return GNUTLS_E_NO_CERTIFICATE_STATUS;
}
wpa_printf(MSG_DEBUG,
"GnuTLS: OCSP status callback - send cached response");
resp->data = gnutls_malloc(len);
if (!resp->data) {
os_free(resp);
return GNUTLS_E_MEMORY_ERROR;
}
os_memcpy(resp->data, cached, len);
resp->size = len;
os_free(cached);
return GNUTLS_E_SUCCESS;
}
#endif /* 3.1.3 */
int tls_global_set_params(void *tls_ctx,
const struct tls_connection_params *params)
{
struct tls_global *global = tls_ctx;
int ret;
/* Currently, global parameters are only set when running in server
* mode. */
global->server = 1;
if (global->params_set) {
gnutls_certificate_free_credentials(global->xcred);
global->params_set = 0;
}
ret = gnutls_certificate_allocate_credentials(&global->xcred);
if (ret) {
wpa_printf(MSG_DEBUG, "Failed to allocate global credentials "
"%s", gnutls_strerror(ret));
return -1;
}
if (params->ca_cert) {
ret = gnutls_certificate_set_x509_trust_file(
global->xcred, params->ca_cert, GNUTLS_X509_FMT_DER);
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read CA cert '%s' "
"in DER format: %s", params->ca_cert,
gnutls_strerror(ret));
ret = gnutls_certificate_set_x509_trust_file(
global->xcred, params->ca_cert,
GNUTLS_X509_FMT_PEM);
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read CA cert "
"'%s' in PEM format: %s",
params->ca_cert,
gnutls_strerror(ret));
goto fail;
}
}
if (params->flags & TLS_CONN_ALLOW_SIGN_RSA_MD5) {
gnutls_certificate_set_verify_flags(
global->xcred,
GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD5);
}
if (params->flags & TLS_CONN_DISABLE_TIME_CHECKS) {
gnutls_certificate_set_verify_flags(
global->xcred,
GNUTLS_VERIFY_DISABLE_TIME_CHECKS);
}
}
if (params->client_cert && params->private_key) {
/* TODO: private_key_passwd? */
ret = gnutls_certificate_set_x509_key_file(
global->xcred, params->client_cert,
params->private_key, GNUTLS_X509_FMT_DER);
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read client cert/key "
"in DER format: %s", gnutls_strerror(ret));
ret = gnutls_certificate_set_x509_key_file(
global->xcred, params->client_cert,
params->private_key, GNUTLS_X509_FMT_PEM);
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read client "
"cert/key in PEM format: %s",
gnutls_strerror(ret));
goto fail;
}
}
} else if (params->private_key) {
int pkcs12_ok = 0;
#ifdef PKCS12_FUNCS
/* Try to load in PKCS#12 format */
ret = gnutls_certificate_set_x509_simple_pkcs12_file(
global->xcred, params->private_key,
GNUTLS_X509_FMT_DER, params->private_key_passwd);
if (ret != 0) {
wpa_printf(MSG_DEBUG, "Failed to load private_key in "
"PKCS#12 format: %s", gnutls_strerror(ret));
goto fail;
} else
pkcs12_ok = 1;
#endif /* PKCS12_FUNCS */
if (!pkcs12_ok) {
wpa_printf(MSG_DEBUG, "GnuTLS: PKCS#12 support not "
"included");
goto fail;
}
}
#if GNUTLS_VERSION_NUMBER >= 0x030103
os_free(global->ocsp_stapling_response);
if (params->ocsp_stapling_response)
global->ocsp_stapling_response =
os_strdup(params->ocsp_stapling_response);
else
global->ocsp_stapling_response = NULL;
gnutls_certificate_set_ocsp_status_request_function(
global->xcred, server_ocsp_status_req, global);
#endif /* 3.1.3 */
global->params_set = 1;
return 0;
fail:
gnutls_certificate_free_credentials(global->xcred);
return -1;
}
int tls_global_set_verify(void *ssl_ctx, int check_crl)
{
/* TODO */
return 0;
}
int tls_connection_set_verify(void *ssl_ctx, struct tls_connection *conn,
int verify_peer, unsigned int flags,
const u8 *session_ctx, size_t session_ctx_len)
{
if (conn == NULL || conn->session == NULL)
return -1;
conn->verify_peer = verify_peer;
gnutls_certificate_server_set_request(conn->session,
verify_peer ? GNUTLS_CERT_REQUIRE
: GNUTLS_CERT_REQUEST);
return 0;
}
int tls_connection_get_random(void *ssl_ctx, struct tls_connection *conn,
struct tls_random *keys)
{
#if GNUTLS_VERSION_NUMBER >= 0x030012
gnutls_datum_t client, server;
if (conn == NULL || conn->session == NULL || keys == NULL)
return -1;
os_memset(keys, 0, sizeof(*keys));
gnutls_session_get_random(conn->session, &client, &server);
keys->client_random = client.data;
keys->server_random = server.data;
keys->client_random_len = client.size;
keys->server_random_len = client.size;
return 0;
#else /* 3.0.18 */
return -1;
#endif /* 3.0.18 */
}
int tls_connection_export_key(void *tls_ctx, struct tls_connection *conn,
const char *label, u8 *out, size_t out_len)
{
if (conn == NULL || conn->session == NULL)
return -1;
return gnutls_prf(conn->session, os_strlen(label), label,
0 /* client_random first */, 0, NULL, out_len,
(char *) out);
}
int tls_connection_get_eap_fast_key(void *tls_ctx, struct tls_connection *conn,
u8 *out, size_t out_len)
{
return -1;
}
static void gnutls_tls_fail_event(struct tls_connection *conn,
const gnutls_datum_t *cert, int depth,
const char *subject, const char *err_str,
enum tls_fail_reason reason)
{
union tls_event_data ev;
struct tls_global *global = conn->global;
struct wpabuf *cert_buf = NULL;
if (global->event_cb == NULL)
return;
os_memset(&ev, 0, sizeof(ev));
ev.cert_fail.depth = depth;
ev.cert_fail.subject = subject ? subject : "";
ev.cert_fail.reason = reason;
ev.cert_fail.reason_txt = err_str;
if (cert) {
cert_buf = wpabuf_alloc_copy(cert->data, cert->size);
ev.cert_fail.cert = cert_buf;
}
global->event_cb(global->cb_ctx, TLS_CERT_CHAIN_FAILURE, &ev);
wpabuf_free(cert_buf);
}
#if GNUTLS_VERSION_NUMBER < 0x030300
static int server_eku_purpose(gnutls_x509_crt_t cert)
{
unsigned int i;
for (i = 0; ; i++) {
char oid[128];
size_t oid_size = sizeof(oid);
int res;
res = gnutls_x509_crt_get_key_purpose_oid(cert, i, oid,
&oid_size, NULL);
if (res == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) {
if (i == 0) {
/* No EKU - assume any use allowed */
return 1;
}
break;
}
if (res < 0) {
wpa_printf(MSG_INFO, "GnuTLS: Failed to get EKU");
return 0;
}
wpa_printf(MSG_DEBUG, "GnuTLS: Certificate purpose: %s", oid);
if (os_strcmp(oid, GNUTLS_KP_TLS_WWW_SERVER) == 0 ||
os_strcmp(oid, GNUTLS_KP_ANY) == 0)
return 1;
}
return 0;
}
#endif /* < 3.3.0 */
static int check_ocsp(struct tls_connection *conn, gnutls_session_t session,
gnutls_alert_description_t *err)
{
#if GNUTLS_VERSION_NUMBER >= 0x030103
gnutls_datum_t response, buf;
gnutls_ocsp_resp_t resp;
unsigned int cert_status;
int res;
if (!(conn->flags & (TLS_CONN_REQUEST_OCSP | TLS_CONN_REQUIRE_OCSP)))
return 0;
if (!gnutls_ocsp_status_request_is_checked(session, 0)) {
if (conn->flags & TLS_CONN_REQUIRE_OCSP) {
wpa_printf(MSG_INFO,
"GnuTLS: No valid OCSP response received");
goto ocsp_error;
}
wpa_printf(MSG_DEBUG,
"GnuTLS: Valid OCSP response was not received - continue since OCSP was not required");
return 0;
}
/*
* GnuTLS has already verified the OCSP response in
* check_ocsp_response() and rejected handshake if the certificate was
* found to be revoked. However, if the response indicates that the
* status is unknown, handshake continues and reaches here. We need to
* re-import the OCSP response to check for unknown certificate status,
* but we do not need to repeat gnutls_ocsp_resp_check_crt() and
* gnutls_ocsp_resp_verify_direct() calls.
*/
res = gnutls_ocsp_status_request_get(session, &response);
if (res != GNUTLS_E_SUCCESS) {
wpa_printf(MSG_INFO,
"GnuTLS: OCSP response was received, but it was not valid");
goto ocsp_error;
}
if (gnutls_ocsp_resp_init(&resp) != GNUTLS_E_SUCCESS)
goto ocsp_error;
res = gnutls_ocsp_resp_import(resp, &response);
if (res != GNUTLS_E_SUCCESS) {
wpa_printf(MSG_INFO,
"GnuTLS: Could not parse received OCSP response: %s",
gnutls_strerror(res));
gnutls_ocsp_resp_deinit(resp);
goto ocsp_error;
}
res = gnutls_ocsp_resp_print(resp, GNUTLS_OCSP_PRINT_FULL, &buf);
if (res == GNUTLS_E_SUCCESS) {
wpa_printf(MSG_DEBUG, "GnuTLS: %s", buf.data);
gnutls_free(buf.data);
}
res = gnutls_ocsp_resp_get_single(resp, 0, NULL, NULL, NULL,
NULL, &cert_status, NULL,
NULL, NULL, NULL);
gnutls_ocsp_resp_deinit(resp);
if (res != GNUTLS_E_SUCCESS) {
wpa_printf(MSG_INFO,
"GnuTLS: Failed to extract OCSP information: %s",
gnutls_strerror(res));
goto ocsp_error;
}
if (cert_status == GNUTLS_OCSP_CERT_GOOD) {
wpa_printf(MSG_DEBUG, "GnuTLS: OCSP cert status: good");
} else if (cert_status == GNUTLS_OCSP_CERT_REVOKED) {
wpa_printf(MSG_DEBUG,
"GnuTLS: OCSP cert status: revoked");
goto ocsp_error;
} else {
wpa_printf(MSG_DEBUG,
"GnuTLS: OCSP cert status: unknown");
if (conn->flags & TLS_CONN_REQUIRE_OCSP)
goto ocsp_error;
wpa_printf(MSG_DEBUG,
"GnuTLS: OCSP was not required, so allow connection to continue");
}
return 0;
ocsp_error:
gnutls_tls_fail_event(conn, NULL, 0, NULL,
"bad certificate status response",
TLS_FAIL_REVOKED);
*err = GNUTLS_A_CERTIFICATE_REVOKED;
return -1;
#else /* GnuTLS 3.1.3 or newer */
return 0;
#endif /* GnuTLS 3.1.3 or newer */
}
static int tls_connection_verify_peer(gnutls_session_t session)
{
struct tls_connection *conn;
unsigned int status, num_certs, i;
struct os_time now;
const gnutls_datum_t *certs;
gnutls_x509_crt_t cert;
gnutls_alert_description_t err;
int res;
conn = gnutls_session_get_ptr(session);
if (!conn->verify_peer) {
wpa_printf(MSG_DEBUG,
"GnuTLS: No peer certificate verification enabled");
return 0;
}
wpa_printf(MSG_DEBUG, "GnuTSL: Verifying peer certificate");
#if GNUTLS_VERSION_NUMBER >= 0x030300
{
gnutls_typed_vdata_st data[1];
unsigned int elements = 0;
os_memset(data, 0, sizeof(data));
if (!conn->global->server) {
data[elements].type = GNUTLS_DT_KEY_PURPOSE_OID;
data[elements].data = (void *) GNUTLS_KP_TLS_WWW_SERVER;
elements++;
}
res = gnutls_certificate_verify_peers(session, data, 1,
&status);
}
#else /* < 3.3.0 */
res = gnutls_certificate_verify_peers2(session, &status);
#endif
if (res < 0) {
wpa_printf(MSG_INFO, "TLS: Failed to verify peer "
"certificate chain");
err = GNUTLS_A_INTERNAL_ERROR;
goto out;
}
#if GNUTLS_VERSION_NUMBER >= 0x030104
{
gnutls_datum_t info;
int ret, type;
type = gnutls_certificate_type_get(session);
ret = gnutls_certificate_verification_status_print(status, type,
&info, 0);
if (ret < 0) {
wpa_printf(MSG_DEBUG,
"GnuTLS: Failed to print verification status");
err = GNUTLS_A_INTERNAL_ERROR;
goto out;
}
wpa_printf(MSG_DEBUG, "GnuTLS: %s", info.data);
gnutls_free(info.data);
}
#endif /* GnuTLS 3.1.4 or newer */
certs = gnutls_certificate_get_peers(session, &num_certs);
if (certs == NULL || num_certs == 0) {
wpa_printf(MSG_INFO, "TLS: No peer certificate chain received");
err = GNUTLS_A_UNKNOWN_CA;
goto out;
}
if (conn->verify_peer && (status & GNUTLS_CERT_INVALID)) {
wpa_printf(MSG_INFO, "TLS: Peer certificate not trusted");
if (status & GNUTLS_CERT_INSECURE_ALGORITHM) {
wpa_printf(MSG_INFO, "TLS: Certificate uses insecure "
"algorithm");
gnutls_tls_fail_event(conn, NULL, 0, NULL,
"certificate uses insecure algorithm",
TLS_FAIL_BAD_CERTIFICATE);
err = GNUTLS_A_INSUFFICIENT_SECURITY;
goto out;
}
if (status & GNUTLS_CERT_NOT_ACTIVATED) {
wpa_printf(MSG_INFO, "TLS: Certificate not yet "
"activated");
gnutls_tls_fail_event(conn, NULL, 0, NULL,
"certificate not yet valid",
TLS_FAIL_NOT_YET_VALID);
err = GNUTLS_A_CERTIFICATE_EXPIRED;
goto out;
}
if (status & GNUTLS_CERT_EXPIRED) {
wpa_printf(MSG_INFO, "TLS: Certificate expired");
gnutls_tls_fail_event(conn, NULL, 0, NULL,
"certificate has expired",
TLS_FAIL_EXPIRED);
err = GNUTLS_A_CERTIFICATE_EXPIRED;
goto out;
}
gnutls_tls_fail_event(conn, NULL, 0, NULL,
"untrusted certificate",
TLS_FAIL_UNTRUSTED);
err = GNUTLS_A_INTERNAL_ERROR;
goto out;
}
if (status & GNUTLS_CERT_SIGNER_NOT_FOUND) {
wpa_printf(MSG_INFO, "TLS: Peer certificate does not have a "
"known issuer");
gnutls_tls_fail_event(conn, NULL, 0, NULL, "signed not found",
TLS_FAIL_UNTRUSTED);
err = GNUTLS_A_UNKNOWN_CA;
goto out;
}
if (status & GNUTLS_CERT_REVOKED) {
wpa_printf(MSG_INFO, "TLS: Peer certificate has been revoked");
gnutls_tls_fail_event(conn, NULL, 0, NULL,
"certificate revoked",
TLS_FAIL_REVOKED);
err = GNUTLS_A_CERTIFICATE_REVOKED;
goto out;
}
if (status != 0) {
wpa_printf(MSG_INFO, "TLS: Unknown verification status: %d",
status);
err = GNUTLS_A_INTERNAL_ERROR;
goto out;
}
if (check_ocsp(conn, session, &err))
goto out;
os_get_time(&now);
for (i = 0; i < num_certs; i++) {
char *buf;
size_t len;
if (gnutls_x509_crt_init(&cert) < 0) {
wpa_printf(MSG_INFO, "TLS: Certificate initialization "
"failed");
err = GNUTLS_A_BAD_CERTIFICATE;
goto out;
}
if (gnutls_x509_crt_import(cert, &certs[i],
GNUTLS_X509_FMT_DER) < 0) {
wpa_printf(MSG_INFO, "TLS: Could not parse peer "
"certificate %d/%d", i + 1, num_certs);
gnutls_x509_crt_deinit(cert);
err = GNUTLS_A_BAD_CERTIFICATE;
goto out;
}
gnutls_x509_crt_get_dn(cert, NULL, &len);
len++;
buf = os_malloc(len + 1);
if (buf) {
buf[0] = buf[len] = '\0';
gnutls_x509_crt_get_dn(cert, buf, &len);
}
wpa_printf(MSG_DEBUG, "TLS: Peer cert chain %d/%d: %s",
i + 1, num_certs, buf);
if (conn->global->event_cb) {
struct wpabuf *cert_buf = NULL;
union tls_event_data ev;
#ifdef CONFIG_SHA256
u8 hash[32];
const u8 *_addr[1];
size_t _len[1];
#endif /* CONFIG_SHA256 */
os_memset(&ev, 0, sizeof(ev));
if (conn->global->cert_in_cb) {
cert_buf = wpabuf_alloc_copy(certs[i].data,
certs[i].size);
ev.peer_cert.cert = cert_buf;
}
#ifdef CONFIG_SHA256
_addr[0] = certs[i].data;
_len[0] = certs[i].size;
if (sha256_vector(1, _addr, _len, hash) == 0) {
ev.peer_cert.hash = hash;
ev.peer_cert.hash_len = sizeof(hash);
}
#endif /* CONFIG_SHA256 */
ev.peer_cert.depth = i;
ev.peer_cert.subject = buf;
conn->global->event_cb(conn->global->cb_ctx,
TLS_PEER_CERTIFICATE, &ev);
wpabuf_free(cert_buf);
}
if (i == 0) {
if (conn->suffix_match &&
!gnutls_x509_crt_check_hostname(
cert, conn->suffix_match)) {
wpa_printf(MSG_WARNING,
"TLS: Domain suffix match '%s' not found",
conn->suffix_match);
gnutls_tls_fail_event(
conn, &certs[i], i, buf,
"Domain suffix mismatch",
TLS_FAIL_DOMAIN_SUFFIX_MISMATCH);
err = GNUTLS_A_BAD_CERTIFICATE;
gnutls_x509_crt_deinit(cert);
os_free(buf);
goto out;
}
#if GNUTLS_VERSION_NUMBER >= 0x030300
if (conn->domain_match &&
!gnutls_x509_crt_check_hostname2(
cert, conn->domain_match,
GNUTLS_VERIFY_DO_NOT_ALLOW_WILDCARDS)) {
wpa_printf(MSG_WARNING,
"TLS: Domain match '%s' not found",
conn->domain_match);
gnutls_tls_fail_event(
conn, &certs[i], i, buf,
"Domain mismatch",
TLS_FAIL_DOMAIN_MISMATCH);
err = GNUTLS_A_BAD_CERTIFICATE;
gnutls_x509_crt_deinit(cert);
os_free(buf);
goto out;
}
#endif /* >= 3.3.0 */
/* TODO: validate altsubject_match.
* For now, any such configuration is rejected in
* tls_connection_set_params() */
#if GNUTLS_VERSION_NUMBER < 0x030300
/*
* gnutls_certificate_verify_peers() not available, so
* need to check EKU separately.
*/
if (!conn->global->server &&
!server_eku_purpose(cert)) {
wpa_printf(MSG_WARNING,
"GnuTLS: No server EKU");
gnutls_tls_fail_event(
conn, &certs[i], i, buf,
"No server EKU",
TLS_FAIL_BAD_CERTIFICATE);
err = GNUTLS_A_BAD_CERTIFICATE;
gnutls_x509_crt_deinit(cert);
os_free(buf);
goto out;
}
#endif /* < 3.3.0 */
}
if (!conn->disable_time_checks &&
(gnutls_x509_crt_get_expiration_time(cert) < now.sec ||
gnutls_x509_crt_get_activation_time(cert) > now.sec)) {
wpa_printf(MSG_INFO, "TLS: Peer certificate %d/%d is "
"not valid at this time",
i + 1, num_certs);
gnutls_tls_fail_event(
conn, &certs[i], i, buf,
"Certificate is not valid at this time",
TLS_FAIL_EXPIRED);
gnutls_x509_crt_deinit(cert);
os_free(buf);
err = GNUTLS_A_CERTIFICATE_EXPIRED;
goto out;
}
os_free(buf);
gnutls_x509_crt_deinit(cert);
}
if (conn->global->event_cb != NULL)
conn->global->event_cb(conn->global->cb_ctx,
TLS_CERT_CHAIN_SUCCESS, NULL);
return 0;
out:
conn->failed++;
gnutls_alert_send(session, GNUTLS_AL_FATAL, err);
return GNUTLS_E_CERTIFICATE_ERROR;
}
static struct wpabuf * gnutls_get_appl_data(struct tls_connection *conn)
{
int res;
struct wpabuf *ad;
wpa_printf(MSG_DEBUG, "GnuTLS: Check for possible Application Data");
ad = wpabuf_alloc((wpabuf_len(conn->pull_buf) + 500) * 3);
if (ad == NULL)
return NULL;
res = gnutls_record_recv(conn->session, wpabuf_mhead(ad),
wpabuf_size(ad));
wpa_printf(MSG_DEBUG, "GnuTLS: gnutls_record_recv: %d", res);
if (res < 0) {
wpa_printf(MSG_DEBUG, "%s - gnutls_record_recv failed: %d "
"(%s)", __func__, (int) res,
gnutls_strerror(res));
wpabuf_free(ad);
return NULL;
}
wpabuf_put(ad, res);
wpa_printf(MSG_DEBUG, "GnuTLS: Received %d bytes of Application Data",
res);
return ad;
}
struct wpabuf * tls_connection_handshake(void *tls_ctx,
struct tls_connection *conn,
const struct wpabuf *in_data,
struct wpabuf **appl_data)
{
struct tls_global *global = tls_ctx;
struct wpabuf *out_data;
int ret;
if (appl_data)
*appl_data = NULL;
if (in_data && wpabuf_len(in_data) > 0) {
if (conn->pull_buf) {
wpa_printf(MSG_DEBUG, "%s - %lu bytes remaining in "
"pull_buf", __func__,
(unsigned long) wpabuf_len(conn->pull_buf));
wpabuf_free(conn->pull_buf);
}
conn->pull_buf = wpabuf_dup(in_data);
if (conn->pull_buf == NULL)
return NULL;
conn->pull_buf_offset = wpabuf_head(conn->pull_buf);
}
ret = gnutls_handshake(conn->session);
if (ret < 0) {
gnutls_alert_description_t alert;
switch (ret) {
case GNUTLS_E_AGAIN:
if (global->server && conn->established &&
conn->push_buf == NULL) {
/* Need to return something to trigger
* completion of EAP-TLS. */
conn->push_buf = wpabuf_alloc(0);
}
break;
case GNUTLS_E_FATAL_ALERT_RECEIVED:
alert = gnutls_alert_get(conn->session);
wpa_printf(MSG_DEBUG, "%s - received fatal '%s' alert",
__func__, gnutls_alert_get_name(alert));
conn->read_alerts++;
if (conn->global->event_cb != NULL) {
union tls_event_data ev;
os_memset(&ev, 0, sizeof(ev));
ev.alert.is_local = 0;
ev.alert.type = gnutls_alert_get_name(alert);
ev.alert.description = ev.alert.type;
conn->global->event_cb(conn->global->cb_ctx,
TLS_ALERT, &ev);
}
/* continue */
default:
wpa_printf(MSG_DEBUG, "%s - gnutls_handshake failed "
"-> %s", __func__, gnutls_strerror(ret));
conn->failed++;
}
} else {
size_t size;
wpa_printf(MSG_DEBUG, "TLS: Handshake completed successfully");
#if GNUTLS_VERSION_NUMBER >= 0x03010a
{
char *desc;
desc = gnutls_session_get_desc(conn->session);
if (desc) {
wpa_printf(MSG_DEBUG, "GnuTLS: %s", desc);
gnutls_free(desc);
}
}
#endif /* GnuTLS 3.1.10 or newer */
conn->established = 1;
if (conn->push_buf == NULL) {
/* Need to return something to get final TLS ACK. */
conn->push_buf = wpabuf_alloc(0);
}
gnutls_session_get_data(conn->session, NULL, &size);
if (global->session_data == NULL ||
global->session_data_size < size) {
os_free(global->session_data);
global->session_data = os_malloc(size);
}
if (global->session_data) {
global->session_data_size = size;
gnutls_session_get_data(conn->session,
global->session_data,
&global->session_data_size);
}
if (conn->pull_buf && appl_data)
*appl_data = gnutls_get_appl_data(conn);
}
out_data = conn->push_buf;
conn->push_buf = NULL;
return out_data;
}
struct wpabuf * tls_connection_server_handshake(void *tls_ctx,
struct tls_connection *conn,
const struct wpabuf *in_data,
struct wpabuf **appl_data)
{
return tls_connection_handshake(tls_ctx, conn, in_data, appl_data);
}
struct wpabuf * tls_connection_encrypt(void *tls_ctx,
struct tls_connection *conn,
const struct wpabuf *in_data)
{
ssize_t res;
struct wpabuf *buf;
res = gnutls_record_send(conn->session, wpabuf_head(in_data),
wpabuf_len(in_data));
if (res < 0) {
wpa_printf(MSG_INFO, "%s: Encryption failed: %s",
__func__, gnutls_strerror(res));
return NULL;
}
buf = conn->push_buf;
conn->push_buf = NULL;
return buf;
}
struct wpabuf * tls_connection_decrypt(void *tls_ctx,
struct tls_connection *conn,
const struct wpabuf *in_data)
{
ssize_t res;
struct wpabuf *out;
if (conn->pull_buf) {
wpa_printf(MSG_DEBUG, "%s - %lu bytes remaining in "
"pull_buf", __func__,
(unsigned long) wpabuf_len(conn->pull_buf));
wpabuf_free(conn->pull_buf);
}
conn->pull_buf = wpabuf_dup(in_data);
if (conn->pull_buf == NULL)
return NULL;
conn->pull_buf_offset = wpabuf_head(conn->pull_buf);
/*
* Even though we try to disable TLS compression, it is possible that
* this cannot be done with all TLS libraries. Add extra buffer space
* to handle the possibility of the decrypted data being longer than
* input data.
*/
out = wpabuf_alloc((wpabuf_len(in_data) + 500) * 3);
if (out == NULL)
return NULL;
res = gnutls_record_recv(conn->session, wpabuf_mhead(out),
wpabuf_size(out));
if (res < 0) {
wpa_printf(MSG_DEBUG, "%s - gnutls_record_recv failed: %d "
"(%s)", __func__, (int) res, gnutls_strerror(res));
wpabuf_free(out);
return NULL;
}
wpabuf_put(out, res);
return out;
}
int tls_connection_resumed(void *ssl_ctx, struct tls_connection *conn)
{
if (conn == NULL)
return 0;
return gnutls_session_is_resumed(conn->session);
}
int tls_connection_set_cipher_list(void *tls_ctx, struct tls_connection *conn,
u8 *ciphers)
{
/* TODO */
return -1;
}
int tls_get_version(void *ssl_ctx, struct tls_connection *conn,
char *buf, size_t buflen)
{
/* TODO */
return -1;
}
int tls_get_cipher(void *ssl_ctx, struct tls_connection *conn,
char *buf, size_t buflen)
{
/* TODO */
buf[0] = '\0';
return 0;
}
int tls_connection_enable_workaround(void *ssl_ctx,
struct tls_connection *conn)
{
gnutls_record_disable_padding(conn->session);
return 0;
}
int tls_connection_client_hello_ext(void *ssl_ctx, struct tls_connection *conn,
int ext_type, const u8 *data,
size_t data_len)
{
/* TODO */
return -1;
}
int tls_connection_get_failed(void *ssl_ctx, struct tls_connection *conn)
{
if (conn == NULL)
return -1;
return conn->failed;
}
int tls_connection_get_read_alerts(void *ssl_ctx, struct tls_connection *conn)
{
if (conn == NULL)
return -1;
return conn->read_alerts;
}
int tls_connection_get_write_alerts(void *ssl_ctx, struct tls_connection *conn)
{
if (conn == NULL)
return -1;
return conn->write_alerts;
}
int tls_connection_set_session_ticket_cb(void *tls_ctx,
struct tls_connection *conn,
tls_session_ticket_cb cb, void *ctx)
{
return -1;
}
int tls_get_library_version(char *buf, size_t buf_len)
{
return os_snprintf(buf, buf_len, "GnuTLS build=%s run=%s",
GNUTLS_VERSION, gnutls_check_version(NULL));
}
void tls_connection_set_success_data(struct tls_connection *conn,
struct wpabuf *data)
{
}
void tls_connection_set_success_data_resumed(struct tls_connection *conn)
{
}
const struct wpabuf *
tls_connection_get_success_data(struct tls_connection *conn)
{
return NULL;
}
void tls_connection_remove_session(struct tls_connection *conn)
{
}