blob: a5d72f407a8d22bc39b983a728ba547164d893be [file] [log] [blame]
/*
* 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 */
#include "common.h"
#include "tls.h"
#define WPA_TLS_RANDOM_SIZE 32
#define WPA_TLS_MASTER_SIZE 48
#if LIBGNUTLS_VERSION_NUMBER < 0x010302
/* GnuTLS 1.3.2 added functions for using master secret. Older versions require
* use of internal structures to get the master_secret and
* {server,client}_random.
*/
#define GNUTLS_INTERNAL_STRUCTURE_HACK
#endif /* LIBGNUTLS_VERSION_NUMBER < 0x010302 */
#ifdef GNUTLS_INTERNAL_STRUCTURE_HACK
/*
* It looks like gnutls does not provide access to client/server_random and
* master_key. This is somewhat unfortunate since these are needed for key
* derivation in EAP-{TLS,TTLS,PEAP,FAST}. Workaround for now is a horrible
* hack that copies the gnutls_session_int definition from gnutls_int.h so that
* we can get the needed information.
*/
typedef u8 uint8;
typedef unsigned char opaque;
typedef struct {
uint8 suite[2];
} cipher_suite_st;
typedef struct {
gnutls_connection_end_t entity;
gnutls_kx_algorithm_t kx_algorithm;
gnutls_cipher_algorithm_t read_bulk_cipher_algorithm;
gnutls_mac_algorithm_t read_mac_algorithm;
gnutls_compression_method_t read_compression_algorithm;
gnutls_cipher_algorithm_t write_bulk_cipher_algorithm;
gnutls_mac_algorithm_t write_mac_algorithm;
gnutls_compression_method_t write_compression_algorithm;
cipher_suite_st current_cipher_suite;
opaque master_secret[WPA_TLS_MASTER_SIZE];
opaque client_random[WPA_TLS_RANDOM_SIZE];
opaque server_random[WPA_TLS_RANDOM_SIZE];
/* followed by stuff we are not interested in */
} security_parameters_st;
struct gnutls_session_int {
security_parameters_st security_parameters;
/* followed by things we are not interested in */
};
#endif /* LIBGNUTLS_VERSION_NUMBER < 0x010302 */
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;
};
struct tls_connection {
gnutls_session session;
char *subject_match, *altsubject_match;
int read_alerts, write_alerts, failed;
u8 *pre_shared_secret;
size_t pre_shared_secret_len;
int established;
int verify_peer;
struct wpabuf *push_buf;
struct wpabuf *pull_buf;
const u8 *pull_buf_offset;
int params_set;
gnutls_certificate_credentials_t xcred;
};
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);
}
extern int wpa_debug_show_keys;
void * tls_init(const struct tls_config *conf)
{
struct tls_global *global;
#ifdef GNUTLS_INTERNAL_STRUCTURE_HACK
/* Because of the horrible hack to get master_secret and client/server
* random, we need to make sure that the gnutls version is something
* that is expected to have same structure definition for the session
* data.. */
const char *ver;
const char *ok_ver[] = { "1.2.3", "1.2.4", "1.2.5", "1.2.6", "1.2.9",
"1.3.2",
NULL };
int i;
#endif /* GNUTLS_INTERNAL_STRUCTURE_HACK */
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++;
#ifdef GNUTLS_INTERNAL_STRUCTURE_HACK
ver = gnutls_check_version(NULL);
if (ver == NULL) {
tls_deinit(global);
return NULL;
}
wpa_printf(MSG_DEBUG, "%s - gnutls version %s", __func__, ver);
for (i = 0; ok_ver[i]; i++) {
if (strcmp(ok_ver[i], ver) == 0)
break;
}
if (ok_ver[i] == NULL) {
wpa_printf(MSG_INFO, "Untested gnutls version %s - this needs "
"to be tested and enabled in tls_gnutls.c", ver);
tls_deinit(global);
return NULL;
}
#endif /* GNUTLS_INTERNAL_STRUCTURE_HACK */
gnutls_global_set_log_function(tls_log_func);
if (wpa_debug_show_keys)
gnutls_global_set_log_level(11);
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);
}
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 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 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)
{
#if LIBGNUTLS_VERSION_NUMBER >= 0x020200
const char *err;
#else /* LIBGNUTLS_VERSION_NUMBER >= 0x020200 */
const int cert_types[2] = { GNUTLS_CRT_X509, 0 };
const int protos[2] = { GNUTLS_TLS1, 0 };
#endif /* LIBGNUTLS_VERSION_NUMBER < 0x020200 */
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;
#if LIBGNUTLS_VERSION_NUMBER >= 0x020200
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;
}
#else /* LIBGNUTLS_VERSION_NUMBER >= 0x020200 */
ret = gnutls_certificate_type_set_priority(conn->session, cert_types);
if (ret < 0)
goto fail;
ret = gnutls_protocol_set_priority(conn->session, protos);
if (ret < 0)
goto fail;
#endif /* LIBGNUTLS_VERSION_NUMBER < 0x020200 */
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) 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;
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);
os_free(conn->subject_match);
os_free(conn->altsubject_match);
wpabuf_free(conn->push_buf);
wpabuf_free(conn->pull_buf);
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;
}
#if 0
static int tls_match_altsubject(X509 *cert, const char *match)
{
GENERAL_NAME *gen;
char *field, *tmp;
void *ext;
int i, found = 0;
size_t len;
ext = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL);
for (i = 0; ext && i < sk_GENERAL_NAME_num(ext); i++) {
gen = sk_GENERAL_NAME_value(ext, i);
switch (gen->type) {
case GEN_EMAIL:
field = "EMAIL";
break;
case GEN_DNS:
field = "DNS";
break;
case GEN_URI:
field = "URI";
break;
default:
field = NULL;
wpa_printf(MSG_DEBUG, "TLS: altSubjectName: "
"unsupported type=%d", gen->type);
break;
}
if (!field)
continue;
wpa_printf(MSG_DEBUG, "TLS: altSubjectName: %s:%s",
field, gen->d.ia5->data);
len = os_strlen(field) + 1 +
strlen((char *) gen->d.ia5->data) + 1;
tmp = os_malloc(len);
if (tmp == NULL)
continue;
snprintf(tmp, len, "%s:%s", field, gen->d.ia5->data);
if (strstr(tmp, match))
found++;
os_free(tmp);
}
return found;
}
#endif
#if 0
static int tls_verify_cb(int preverify_ok, X509_STORE_CTX *x509_ctx)
{
char buf[256];
X509 *err_cert;
int err, depth;
SSL *ssl;
struct tls_connection *conn;
char *match, *altmatch;
err_cert = X509_STORE_CTX_get_current_cert(x509_ctx);
err = X509_STORE_CTX_get_error(x509_ctx);
depth = X509_STORE_CTX_get_error_depth(x509_ctx);
ssl = X509_STORE_CTX_get_ex_data(x509_ctx,
SSL_get_ex_data_X509_STORE_CTX_idx());
X509_NAME_oneline(X509_get_subject_name(err_cert), buf, sizeof(buf));
conn = SSL_get_app_data(ssl);
match = conn ? conn->subject_match : NULL;
altmatch = conn ? conn->altsubject_match : NULL;
if (!preverify_ok) {
wpa_printf(MSG_WARNING, "TLS: Certificate verification failed,"
" error %d (%s) depth %d for '%s'", err,
X509_verify_cert_error_string(err), depth, buf);
} else {
wpa_printf(MSG_DEBUG, "TLS: tls_verify_cb - "
"preverify_ok=%d err=%d (%s) depth=%d buf='%s'",
preverify_ok, err,
X509_verify_cert_error_string(err), depth, buf);
if (depth == 0 && match && strstr(buf, match) == NULL) {
wpa_printf(MSG_WARNING, "TLS: Subject '%s' did not "
"match with '%s'", buf, match);
preverify_ok = 0;
} else if (depth == 0 && altmatch &&
!tls_match_altsubject(err_cert, altmatch)) {
wpa_printf(MSG_WARNING, "TLS: altSubjectName match "
"'%s' not found", altmatch);
preverify_ok = 0;
}
}
return preverify_ok;
}
#endif
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;
os_free(conn->subject_match);
conn->subject_match = NULL;
if (params->subject_match) {
conn->subject_match = os_strdup(params->subject_match);
if (conn->subject_match == NULL)
return -1;
}
os_free(conn->altsubject_match);
conn->altsubject_match = NULL;
if (params->altsubject_match) {
conn->altsubject_match = os_strdup(params->altsubject_match);
if (conn->altsubject_match == NULL)
return -1;
}
/* TODO: gnutls_certificate_set_verify_flags(xcred, flags);
* to force peer validation(?) */
if (params->ca_cert) {
conn->verify_peer = 1;
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));
ret = gnutls_certificate_set_x509_trust_file(
conn->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));
return -1;
}
}
if (params->flags & TLS_CONN_ALLOW_SIGN_RSA_MD5) {
gnutls_certificate_set_verify_flags(
conn->xcred, GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD5);
}
#if LIBGNUTLS_VERSION_NUMBER >= 0x020800
if (params->flags & TLS_CONN_DISABLE_TIME_CHECKS) {
gnutls_certificate_set_verify_flags(
conn->xcred,
GNUTLS_VERIFY_DISABLE_TIME_CHECKS);
}
#endif /* LIBGNUTLS_VERSION_NUMBER >= 0x020800 */
}
if (params->client_cert && params->private_key) {
/* TODO: private_key_passwd? */
ret = gnutls_certificate_set_x509_key_file(
conn->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));
ret = gnutls_certificate_set_x509_key_file(
conn->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));
return ret;
}
}
} else if (params->private_key) {
int pkcs12_ok = 0;
#ifdef PKCS12_FUNCS
/* Try to load in PKCS#12 format */
#if LIBGNUTLS_VERSION_NUMBER >= 0x010302
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 /* LIBGNUTLS_VERSION_NUMBER >= 0x010302 */
#endif /* PKCS12_FUNCS */
if (!pkcs12_ok) {
wpa_printf(MSG_DEBUG, "GnuTLS: PKCS#12 support not "
"included");
return -1;
}
}
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;
}
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_PEM);
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read CA cert '%s' "
"in PEM format: %s", params->ca_cert,
gnutls_strerror(ret));
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));
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 LIBGNUTLS_VERSION_NUMBER >= 0x020800
if (params->flags & TLS_CONN_DISABLE_TIME_CHECKS) {
gnutls_certificate_set_verify_flags(
global->xcred,
GNUTLS_VERIFY_DISABLE_TIME_CHECKS);
}
#endif /* LIBGNUTLS_VERSION_NUMBER >= 0x020800 */
}
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_PEM);
if (ret < 0) {
wpa_printf(MSG_DEBUG, "Failed to read client cert/key "
"in PEM format: %s", gnutls_strerror(ret));
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));
goto fail;
}
}
} else if (params->private_key) {
int pkcs12_ok = 0;
#ifdef PKCS12_FUNCS
/* Try to load in PKCS#12 format */
#if LIBGNUTLS_VERSION_NUMBER >= 0x010302
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 /* LIBGNUTLS_VERSION_NUMBER >= 0x010302 */
#endif /* PKCS12_FUNCS */
if (!pkcs12_ok) {
wpa_printf(MSG_DEBUG, "GnuTLS: PKCS#12 support not "
"included");
goto fail;
}
}
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)
{
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_keys(void *ssl_ctx, struct tls_connection *conn,
struct tls_keys *keys)
{
#ifdef GNUTLS_INTERNAL_STRUCTURE_HACK
security_parameters_st *sec;
#endif /* GNUTLS_INTERNAL_STRUCTURE_HACK */
if (conn == NULL || conn->session == NULL || keys == NULL)
return -1;
os_memset(keys, 0, sizeof(*keys));
#if LIBGNUTLS_VERSION_NUMBER < 0x020c00
#ifdef GNUTLS_INTERNAL_STRUCTURE_HACK
sec = &conn->session->security_parameters;
keys->master_key = sec->master_secret;
keys->master_key_len = WPA_TLS_MASTER_SIZE;
keys->client_random = sec->client_random;
keys->server_random = sec->server_random;
#else /* GNUTLS_INTERNAL_STRUCTURE_HACK */
keys->client_random =
(u8 *) gnutls_session_get_client_random(conn->session);
keys->server_random =
(u8 *) gnutls_session_get_server_random(conn->session);
/* No access to master_secret */
#endif /* GNUTLS_INTERNAL_STRUCTURE_HACK */
#endif /* LIBGNUTLS_VERSION_NUMBER < 0x020c00 */
#if LIBGNUTLS_VERSION_NUMBER < 0x020c00
keys->client_random_len = WPA_TLS_RANDOM_SIZE;
keys->server_random_len = WPA_TLS_RANDOM_SIZE;
#endif /* LIBGNUTLS_VERSION_NUMBER < 0x020c00 */
return 0;
}
int tls_connection_prf(void *tls_ctx, struct tls_connection *conn,
const char *label, int server_random_first,
u8 *out, size_t out_len)
{
#if LIBGNUTLS_VERSION_NUMBER >= 0x010302
if (conn == NULL || conn->session == NULL)
return -1;
return gnutls_prf(conn->session, os_strlen(label), label,
server_random_first, 0, NULL, out_len, (char *) out);
#else /* LIBGNUTLS_VERSION_NUMBER >= 0x010302 */
return -1;
#endif /* LIBGNUTLS_VERSION_NUMBER >= 0x010302 */
}
static int tls_connection_verify_peer(struct tls_connection *conn,
gnutls_alert_description_t *err)
{
unsigned int status, num_certs, i;
struct os_time now;
const gnutls_datum_t *certs;
gnutls_x509_crt_t cert;
if (gnutls_certificate_verify_peers2(conn->session, &status) < 0) {
wpa_printf(MSG_INFO, "TLS: Failed to verify peer "
"certificate chain");
*err = GNUTLS_A_INTERNAL_ERROR;
return -1;
}
if (conn->verify_peer && (status & GNUTLS_CERT_INVALID)) {
wpa_printf(MSG_INFO, "TLS: Peer certificate not trusted");
*err = GNUTLS_A_INTERNAL_ERROR;
if (status & GNUTLS_CERT_INSECURE_ALGORITHM) {
wpa_printf(MSG_INFO, "TLS: Certificate uses insecure "
"algorithm");
*err = GNUTLS_A_INSUFFICIENT_SECURITY;
}
#if LIBGNUTLS_VERSION_NUMBER >= 0x020800
if (status & GNUTLS_CERT_NOT_ACTIVATED) {
wpa_printf(MSG_INFO, "TLS: Certificate not yet "
"activated");
*err = GNUTLS_A_CERTIFICATE_EXPIRED;
}
if (status & GNUTLS_CERT_EXPIRED) {
wpa_printf(MSG_INFO, "TLS: Certificate expired");
*err = GNUTLS_A_CERTIFICATE_EXPIRED;
}
#endif /* LIBGNUTLS_VERSION_NUMBER >= 0x020800 */
return -1;
}
if (status & GNUTLS_CERT_SIGNER_NOT_FOUND) {
wpa_printf(MSG_INFO, "TLS: Peer certificate does not have a "
"known issuer");
*err = GNUTLS_A_UNKNOWN_CA;
return -1;
}
if (status & GNUTLS_CERT_REVOKED) {
wpa_printf(MSG_INFO, "TLS: Peer certificate has been revoked");
*err = GNUTLS_A_CERTIFICATE_REVOKED;
return -1;
}
os_get_time(&now);
certs = gnutls_certificate_get_peers(conn->session, &num_certs);
if (certs == NULL) {
wpa_printf(MSG_INFO, "TLS: No peer certificate chain "
"received");
*err = GNUTLS_A_UNKNOWN_CA;
return -1;
}
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;
return -1;
}
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;
return -1;
}
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 (i == 0) {
/* TODO: validate subject_match and altsubject_match */
}
os_free(buf);
if (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_x509_crt_deinit(cert);
*err = GNUTLS_A_CERTIFICATE_EXPIRED;
return -1;
}
gnutls_x509_crt_deinit(cert);
}
return 0;
}
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) {
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:
wpa_printf(MSG_DEBUG, "%s - received fatal '%s' alert",
__func__, gnutls_alert_get_name(
gnutls_alert_get(conn->session)));
conn->read_alerts++;
/* continue */
default:
wpa_printf(MSG_DEBUG, "%s - gnutls_handshake failed "
"-> %s", __func__, gnutls_strerror(ret));
conn->failed++;
}
} else {
size_t size;
gnutls_alert_description_t err;
if (conn->verify_peer &&
tls_connection_verify_peer(conn, &err)) {
wpa_printf(MSG_INFO, "TLS: Peer certificate chain "
"failed validation");
conn->failed++;
gnutls_alert_send(conn->session, GNUTLS_AL_FATAL, err);
goto out;
}
wpa_printf(MSG_DEBUG, "TLS: Handshake completed successfully");
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:
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_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_get_keyblock_size(void *tls_ctx,
struct tls_connection *conn)
{
/* TODO */
return -1;
}
unsigned int tls_capabilities(void *tls_ctx)
{
return 0;
}
int tls_connection_set_session_ticket_cb(void *tls_ctx,
struct tls_connection *conn,
tls_session_ticket_cb cb, void *ctx)
{
return -1;
}