trunk/src/tls_gnutls.c

/*
 *  ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
 *
 *  Copyright (c) 2015 Attila Molnar <attilamolnar@hush.com>
 *  Copyright (c) 2015 Adam <Adam@anope.org>
 *  Copyright (c) 2015-2016 ircd-hybrid development team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
 *  USA
 */

/*! \file tls_gnutls.c
 * \brief Includes all GnuTLS-specific TLS functions
 * \version $Id$
 */

#include "stdinc.h"
#include "tls.h"
#include "conf.h"
#include "log.h"
#include "misc.h"
#include "memory.h"

#ifdef HAVE_TLS_GNUTLS

void
tls_init(void)
{
}

static void
tls_free_cred(tls_context_t cred)
{
  gnutls_priority_deinit(cred->priorities);
  gnutls_dh_params_deinit(cred->dh_params);
  gnutls_certificate_free_credentials(cred->x509_cred);

  gnutls_global_deinit();

  xfree(cred);
}

int
tls_new_cred(void)
{
  int ret;
  struct gnutls_context *context;

  if (!ConfigServerInfo.ssl_certificate_file || !ConfigServerInfo.rsa_private_key_file)
    return 0;

  context = xcalloc(sizeof(*context));

  gnutls_global_init();

  ret = gnutls_certificate_allocate_credentials(&context->x509_cred);
  if (ret != GNUTLS_E_SUCCESS)
  {
    ilog(LOG_TYPE_IRCD, "ERROR: Could not initialize the TLS credentials -- %s", gnutls_strerror(ret));
    xfree(context);
    return 0;
  }

  /* TBD: set ciphers based on serverinfo::ssl_cipher_list */

  gnutls_priority_init(&context->priorities, "NORMAL:%SERVER_PRECEDENCE:!VERS-SSL3.0", NULL);

  ret = gnutls_certificate_set_x509_key_file(context->x509_cred, ConfigServerInfo.ssl_certificate_file, ConfigServerInfo.rsa_private_key_file, GNUTLS_X509_FMT_PEM);
  if (ret != GNUTLS_E_SUCCESS)
  {
    ilog(LOG_TYPE_IRCD, "Could not set TLS keys -- %s", gnutls_strerror(ret));

    gnutls_certificate_free_credentials(context->x509_cred);
    gnutls_priority_deinit(context->priorities);
    xfree(context);
    return 0;
  }

  gnutls_dh_params_init(&context->dh_params);

  if (ConfigServerInfo.ssl_dh_param_file)
  {
    gnutls_datum_t data;

    ret = gnutls_load_file(ConfigServerInfo.ssl_dh_param_file, &data);

    if (ret != GNUTLS_E_SUCCESS)
      ilog(LOG_TYPE_IRCD, "Ignoring serverinfo::ssl_dh_param_file -- unable to load file -- %s", gnutls_strerror(ret));
    else
    {
      ret = gnutls_dh_params_import_pkcs3(context->dh_params, &data, GNUTLS_X509_FMT_PEM);

      if (ret != GNUTLS_E_SUCCESS)
        ilog(LOG_TYPE_IRCD, "Ignoring serverinfo::ssl_dh_param_file -- unable to import dh params -- %s", gnutls_strerror(ret));

      gnutls_free(data.data);
    }
  }

  gnutls_certificate_set_dh_params(context->x509_cred, context->dh_params);

  if (ConfigServerInfo.ssl_message_digest_algorithm == NULL)
    ConfigServerInfo.message_digest_algorithm = GNUTLS_DIG_SHA256;
  else
  {
    ConfigServerInfo.message_digest_algorithm = gnutls_digest_get_id(ConfigServerInfo.ssl_message_digest_algorithm);

    if (ConfigServerInfo.message_digest_algorithm == GNUTLS_DIG_UNKNOWN)
    {
      ConfigServerInfo.message_digest_algorithm = GNUTLS_DIG_SHA256;
      ilog(LOG_TYPE_IRCD, "Ignoring serverinfo::ssl_message_digest_algorithm -- unknown message digest algorithm");
    }
  }

  if (ConfigServerInfo.tls_ctx && --ConfigServerInfo.tls_ctx->refs == 0)
    tls_free_cred(ConfigServerInfo.tls_ctx);

  ConfigServerInfo.tls_ctx = context;
  ++context->refs;

  return 1;
}

const char *
tls_get_cipher(const tls_data_t *tls_data)
{
  static char buffer[IRCD_BUFSIZE];

  snprintf(buffer, sizeof(buffer), "%s-%s-%s-%s",
           gnutls_protocol_get_name(gnutls_protocol_get_version(tls_data->session)),
           gnutls_kx_get_name(gnutls_kx_get(tls_data->session)),
           gnutls_cipher_get_name(gnutls_cipher_get(tls_data->session)),
           gnutls_mac_get_name(gnutls_mac_get(tls_data->session)));

  return buffer;
}

int
tls_isusing(tls_data_t *tls_data)
{
  return tls_data->session != NULL;
}

void
tls_free(tls_data_t *tls_data)
{
  gnutls_deinit(tls_data->session);
}

int
tls_read(tls_data_t *tls_data, char *buf, size_t bufsize, int *want_write)
{
  int length = gnutls_record_recv(tls_data->session, buf, bufsize);

  if (length <= 0)
  {
    switch (length)
    {
      case GNUTLS_E_AGAIN:
      case GNUTLS_E_INTERRUPTED:
        errno = EWOULDBLOCK;
        return -1;
      case 0:  /* Closed */
      default:  /* Other error */
        /* XXX can gnutls_strerror(length) if <0 for gnutls's idea of the reason */
        return 0;
    }
  }

  return length;
}

int
tls_write(tls_data_t *tls_data, const char *buf, size_t bufsize, int *want_read)
{
  int length = gnutls_record_send(tls_data->session, buf, bufsize);

  if (length <= 0)
  {
    switch (length)
    {
      case GNUTLS_E_AGAIN:
      case GNUTLS_E_INTERRUPTED:
      case 0:
        errno = EWOULDBLOCK;
        return -1;
      default:
        return 0;
    }
  }

  return length;
}

void
tls_shutdown(tls_data_t *tls_data)
{
  gnutls_bye(tls_data->session, GNUTLS_SHUT_WR);

  if (--tls_data->context->refs == 0)
    tls_free_cred(tls_data->context);
}

int
tls_new(tls_data_t *tls_data, int fd, tls_role_t role)
{
  gnutls_init(&tls_data->session, role == TLS_ROLE_SERVER ? GNUTLS_SERVER : GNUTLS_CLIENT);

  tls_data->context = ConfigServerInfo.tls_ctx;
  ++tls_data->context->refs;

  gnutls_priority_set(tls_data->session, tls_data->context->priorities);
  gnutls_credentials_set(tls_data->session, GNUTLS_CRD_CERTIFICATE, tls_data->context->x509_cred);
  gnutls_dh_set_prime_bits(tls_data->session, 1024);
  gnutls_transport_set_int(tls_data->session, fd);

  if (role == TLS_ROLE_SERVER)
    /* Request client certificate if any. */
    gnutls_certificate_server_set_request(tls_data->session, GNUTLS_CERT_REQUEST);

  return 1;
}

int
tls_set_ciphers(tls_data_t *tls_data, const char *cipher_list)
{
  int ret;
  const char *prioerror;

  gnutls_priority_deinit(tls_data->context->priorities);

  ret = gnutls_priority_init(&tls_data->context->priorities, cipher_list, &prioerror);
  if (ret != GNUTLS_E_SUCCESS)
  {
    /* GnuTLS did not understand the user supplied string, log and fall back to the default priorities */
    ilog(LOG_TYPE_IRCD, "Failed to set GnuTLS priorities to \"%s\": %s Syntax error at position %u, falling back to default (NORMAL:%%SERVER_PRECEDENCE:!VERS-SSL3.0)",
         cipher_list, gnutls_strerror(ret), (unsigned int)(prioerror - cipher_list));
    gnutls_priority_init(&tls_data->context->priorities, "NORMAL:%SERVER_PRECEDENCE:!VERS-SSL3.0", NULL);
    return 0;
  }

  return 1;
}

tls_handshake_status_t
tls_handshake(tls_data_t *tls_data, tls_role_t role, const char **errstr)
{
  int ret = gnutls_handshake(tls_data->session);

  if (ret >= 0)
    return TLS_HANDSHAKE_DONE;

  if (ret == GNUTLS_E_AGAIN || ret == GNUTLS_E_INTERRUPTED)
  {
    /* Handshake needs resuming later, read() or write() would have blocked. */

    if (gnutls_record_get_direction(tls_data->session) == 0)
    {
      /* gnutls_handshake() wants to read() again. */
      return TLS_HANDSHAKE_WANT_READ;
    }
    else
    {
      /* gnutls_handshake() wants to write() again. */
      return TLS_HANDSHAKE_WANT_WRITE;
    }
  }
  else
  {
    const char *error = gnutls_strerror(ret);

    if (errstr)
      *errstr = error;

    return TLS_HANDSHAKE_ERROR;
  }
}

int
tls_verify_cert(tls_data_t *tls_data, tls_md_t digest, char **fingerprint)
{
  int ret;
  gnutls_x509_crt_t cert;
  const gnutls_datum_t *cert_list;
  unsigned int cert_list_size = 0;
  unsigned char digestbuf[TLS_GNUTLS_MAX_HASH_SIZE];
  size_t digest_size = sizeof(digestbuf);
  char buf[TLS_GNUTLS_MAX_HASH_SIZE * 2 + 1];

  cert_list = gnutls_certificate_get_peers(tls_data->session, &cert_list_size);
  if (!cert_list)
    return 1;  /* No certificate */

  ret = gnutls_x509_crt_init(&cert);
  if (ret != GNUTLS_E_SUCCESS)
    return 1;

  ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
  if (ret != GNUTLS_E_SUCCESS)
    goto info_done_dealloc;

  ret = gnutls_x509_crt_get_fingerprint(cert, digest, digestbuf, &digest_size);
  if (ret != GNUTLS_E_SUCCESS)
    goto info_done_dealloc;

  binary_to_hex(digestbuf, buf, digest_size);
  *fingerprint = xstrdup(buf);

  gnutls_x509_crt_deinit(cert);
  return 1;

info_done_dealloc:
  gnutls_x509_crt_deinit(cert);
  return 0;
}
#endif  /* HAVE_TLS_GNUTLS */
Revision:	7196
Committed:	Sat Jan 30 19:42:30 2016 UTC (9 years, 6 months ago) by michael
Content type:	text/x-csrc
File size:	8962 byte(s)
Log Message:	- tls_gnutls.c: explicitly disable SSLv3 for releases prior to 3.4
#	User	Rev	Content
1	michael	7105	/*
2			* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3			*
4	michael	7148	* Copyright (c) 2015 Attila Molnar <attilamolnar@hush.com>
5			* Copyright (c) 2015 Adam <Adam@anope.org>
6	michael	7164	* Copyright (c) 2015-2016 ircd-hybrid development team
7	michael	7105	*
8			* This program is free software; you can redistribute it and/or modify
9			* it under the terms of the GNU General Public License as published by
10			* the Free Software Foundation; either version 2 of the License, or
11			* (at your option) any later version.
12			*
13			* This program is distributed in the hope that it will be useful,
14			* but WITHOUT ANY WARRANTY; without even the implied warranty of
15			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16			* GNU General Public License for more details.
17			*
18			* You should have received a copy of the GNU General Public License
19			* along with this program; if not, write to the Free Software
20			* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
21			* USA
22			*/
23
24			/*! \file tls_gnutls.c
25			* \brief Includes all GnuTLS-specific TLS functions
26			* \version $Id$
27			*/
28
29			#include "stdinc.h"
30			#include "tls.h"
31			#include "conf.h"
32			#include "log.h"
33	michael	7152	#include "misc.h"
34	michael	7105	#include "memory.h"
35
36			#ifdef HAVE_TLS_GNUTLS
37
38			void
39			tls_init(void)
40			{
41			}
42
43			static void
44			tls_free_cred(tls_context_t cred)
45			{
46			gnutls_priority_deinit(cred->priorities);
47			gnutls_dh_params_deinit(cred->dh_params);
48			gnutls_certificate_free_credentials(cred->x509_cred);
49
50			gnutls_global_deinit();
51
52			xfree(cred);
53			}
54
55			int
56			tls_new_cred(void)
57			{
58			int ret;
59			struct gnutls_context *context;
60
61			if (!ConfigServerInfo.ssl_certificate_file \|\| !ConfigServerInfo.rsa_private_key_file)
62			return 0;
63
64			context = xcalloc(sizeof(*context));
65
66			gnutls_global_init();
67
68			ret = gnutls_certificate_allocate_credentials(&context->x509_cred);
69	michael	7134	if (ret != GNUTLS_E_SUCCESS)
70	michael	7105	{
71	michael	7134	ilog(LOG_TYPE_IRCD, "ERROR: Could not initialize the TLS credentials -- %s", gnutls_strerror(ret));
72	michael	7105	xfree(context);
73			return 0;
74			}
75
76	michael	7193	/* TBD: set ciphers based on serverinfo::ssl_cipher_list */
77	michael	7105
78	michael	7196	gnutls_priority_init(&context->priorities, "NORMAL:%SERVER_PRECEDENCE:!VERS-SSL3.0", NULL);
79	michael	7193
80	michael	7105	ret = gnutls_certificate_set_x509_key_file(context->x509_cred, ConfigServerInfo.ssl_certificate_file, ConfigServerInfo.rsa_private_key_file, GNUTLS_X509_FMT_PEM);
81	michael	7134	if (ret != GNUTLS_E_SUCCESS)
82	michael	7105	{
83			ilog(LOG_TYPE_IRCD, "Could not set TLS keys -- %s", gnutls_strerror(ret));
84
85			gnutls_certificate_free_credentials(context->x509_cred);
86			gnutls_priority_deinit(context->priorities);
87			xfree(context);
88			return 0;
89			}
90
91			gnutls_dh_params_init(&context->dh_params);
92
93			if (ConfigServerInfo.ssl_dh_param_file)
94			{
95			gnutls_datum_t data;
96
97			ret = gnutls_load_file(ConfigServerInfo.ssl_dh_param_file, &data);
98
99			if (ret != GNUTLS_E_SUCCESS)
100			ilog(LOG_TYPE_IRCD, "Ignoring serverinfo::ssl_dh_param_file -- unable to load file -- %s", gnutls_strerror(ret));
101			else
102			{
103			ret = gnutls_dh_params_import_pkcs3(context->dh_params, &data, GNUTLS_X509_FMT_PEM);
104
105			if (ret != GNUTLS_E_SUCCESS)
106			ilog(LOG_TYPE_IRCD, "Ignoring serverinfo::ssl_dh_param_file -- unable to import dh params -- %s", gnutls_strerror(ret));
107
108			gnutls_free(data.data);
109			}
110			}
111
112			gnutls_certificate_set_dh_params(context->x509_cred, context->dh_params);
113
114			if (ConfigServerInfo.ssl_message_digest_algorithm == NULL)
115			ConfigServerInfo.message_digest_algorithm = GNUTLS_DIG_SHA256;
116			else
117			{
118			ConfigServerInfo.message_digest_algorithm = gnutls_digest_get_id(ConfigServerInfo.ssl_message_digest_algorithm);
119
120			if (ConfigServerInfo.message_digest_algorithm == GNUTLS_DIG_UNKNOWN)
121			{
122			ConfigServerInfo.message_digest_algorithm = GNUTLS_DIG_SHA256;
123			ilog(LOG_TYPE_IRCD, "Ignoring serverinfo::ssl_message_digest_algorithm -- unknown message digest algorithm");
124			}
125			}
126
127			if (ConfigServerInfo.tls_ctx && --ConfigServerInfo.tls_ctx->refs == 0)
128			tls_free_cred(ConfigServerInfo.tls_ctx);
129
130			ConfigServerInfo.tls_ctx = context;
131			++context->refs;
132
133			return 1;
134			}
135
136			const char *
137			tls_get_cipher(const tls_data_t *tls_data)
138			{
139			static char buffer[IRCD_BUFSIZE];
140
141	michael	7120	snprintf(buffer, sizeof(buffer), "%s-%s-%s-%s",
142			gnutls_protocol_get_name(gnutls_protocol_get_version(tls_data->session)),
143	michael	7105	gnutls_kx_get_name(gnutls_kx_get(tls_data->session)),
144			gnutls_cipher_get_name(gnutls_cipher_get(tls_data->session)),
145			gnutls_mac_get_name(gnutls_mac_get(tls_data->session)));
146
147			return buffer;
148			}
149
150			int
151			tls_isusing(tls_data_t *tls_data)
152			{
153			return tls_data->session != NULL;
154			}
155
156			void
157			tls_free(tls_data_t *tls_data)
158			{
159			gnutls_deinit(tls_data->session);
160			}
161
162			int
163			tls_read(tls_data_t tls_data, char buf, size_t bufsize, int *want_write)
164			{
165			int length = gnutls_record_recv(tls_data->session, buf, bufsize);
166
167			if (length <= 0)
168			{
169			switch (length)
170			{
171			case GNUTLS_E_AGAIN:
172			case GNUTLS_E_INTERRUPTED:
173			errno = EWOULDBLOCK;
174	michael	7146	return -1;
175	michael	7105	case 0: /* Closed */
176			default: /* Other error */
177	michael	7146	/* XXX can gnutls_strerror(length) if <0 for gnutls's idea of the reason */
178			return 0;
179	michael	7105	}
180			}
181
182			return length;
183			}
184
185			int
186			tls_write(tls_data_t tls_data, const char buf, size_t bufsize, int *want_read)
187			{
188			int length = gnutls_record_send(tls_data->session, buf, bufsize);
189
190			if (length <= 0)
191			{
192			switch (length)
193			{
194			case GNUTLS_E_AGAIN:
195			case GNUTLS_E_INTERRUPTED:
196			case 0:
197			errno = EWOULDBLOCK;
198	michael	7146	return -1;
199	michael	7105	default:
200	michael	7146	return 0;
201	michael	7105	}
202			}
203
204			return length;
205			}
206
207			void
208			tls_shutdown(tls_data_t *tls_data)
209			{
210			gnutls_bye(tls_data->session, GNUTLS_SHUT_WR);
211
212			if (--tls_data->context->refs == 0)
213			tls_free_cred(tls_data->context);
214			}
215
216			int
217			tls_new(tls_data_t *tls_data, int fd, tls_role_t role)
218			{
219			gnutls_init(&tls_data->session, role == TLS_ROLE_SERVER ? GNUTLS_SERVER : GNUTLS_CLIENT);
220
221			tls_data->context = ConfigServerInfo.tls_ctx;
222			++tls_data->context->refs;
223
224			gnutls_priority_set(tls_data->session, tls_data->context->priorities);
225			gnutls_credentials_set(tls_data->session, GNUTLS_CRD_CERTIFICATE, tls_data->context->x509_cred);
226			gnutls_dh_set_prime_bits(tls_data->session, 1024);
227			gnutls_transport_set_int(tls_data->session, fd);
228
229			if (role == TLS_ROLE_SERVER)
230			/* Request client certificate if any. */
231			gnutls_certificate_server_set_request(tls_data->session, GNUTLS_CERT_REQUEST);
232
233			return 1;
234			}
235
236			int
237			tls_set_ciphers(tls_data_t tls_data, const char cipher_list)
238			{
239			int ret;
240			const char *prioerror;
241
242			gnutls_priority_deinit(tls_data->context->priorities);
243
244			ret = gnutls_priority_init(&tls_data->context->priorities, cipher_list, &prioerror);
245	michael	7134	if (ret != GNUTLS_E_SUCCESS)
246	michael	7105	{
247			/* GnuTLS did not understand the user supplied string, log and fall back to the default priorities */
248	michael	7196	ilog(LOG_TYPE_IRCD, "Failed to set GnuTLS priorities to \"%s\": %s Syntax error at position %u, falling back to default (NORMAL:%%SERVER_PRECEDENCE:!VERS-SSL3.0)",
249	michael	7105	cipher_list, gnutls_strerror(ret), (unsigned int)(prioerror - cipher_list));
250	michael	7196	gnutls_priority_init(&tls_data->context->priorities, "NORMAL:%SERVER_PRECEDENCE:!VERS-SSL3.0", NULL);
251	michael	7105	return 0;
252			}
253
254			return 1;
255			}
256
257			tls_handshake_status_t
258			tls_handshake(tls_data_t tls_data, tls_role_t role, const char *errstr)
259			{
260			int ret = gnutls_handshake(tls_data->session);
261
262			if (ret >= 0)
263			return TLS_HANDSHAKE_DONE;
264
265			if (ret == GNUTLS_E_AGAIN \|\| ret == GNUTLS_E_INTERRUPTED)
266			{
267			/* Handshake needs resuming later, read() or write() would have blocked. */
268
269			if (gnutls_record_get_direction(tls_data->session) == 0)
270			{
271			/* gnutls_handshake() wants to read() again. */
272			return TLS_HANDSHAKE_WANT_READ;
273			}
274			else
275			{
276			/* gnutls_handshake() wants to write() again. */
277			return TLS_HANDSHAKE_WANT_WRITE;
278			}
279			}
280			else
281			{
282			const char *error = gnutls_strerror(ret);
283
284			if (errstr)
285			*errstr = error;
286
287			return TLS_HANDSHAKE_ERROR;
288			}
289			}
290
291			int
292	michael	7142	tls_verify_cert(tls_data_t tls_data, tls_md_t digest, char *fingerprint)
293	michael	7105	{
294			int ret;
295			gnutls_x509_crt_t cert;
296			const gnutls_datum_t *cert_list;
297			unsigned int cert_list_size = 0;
298	michael	7134	unsigned char digestbuf[TLS_GNUTLS_MAX_HASH_SIZE];
299	michael	7105	size_t digest_size = sizeof(digestbuf);
300	michael	7134	char buf[TLS_GNUTLS_MAX_HASH_SIZE * 2 + 1];
301	michael	7105
302			cert_list = gnutls_certificate_get_peers(tls_data->session, &cert_list_size);
303			if (!cert_list)
304			return 1; /* No certificate */
305
306			ret = gnutls_x509_crt_init(&cert);
307	michael	7134	if (ret != GNUTLS_E_SUCCESS)
308	michael	7105	return 1;
309
310			ret = gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER);
311	michael	7134	if (ret != GNUTLS_E_SUCCESS)
312	michael	7105	goto info_done_dealloc;
313
314			ret = gnutls_x509_crt_get_fingerprint(cert, digest, digestbuf, &digest_size);
315	michael	7134	if (ret != GNUTLS_E_SUCCESS)
316	michael	7105	goto info_done_dealloc;
317
318			binary_to_hex(digestbuf, buf, digest_size);
319			*fingerprint = xstrdup(buf);
320
321	michael	7145	gnutls_x509_crt_deinit(cert);
322	michael	7105	return 1;
323
324			info_done_dealloc:
325			gnutls_x509_crt_deinit(cert);
326			return 0;
327			}
328			#endif /* HAVE_TLS_GNUTLS */