trunk/src/auth.c

/*
 *  ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
 *
 *  Copyright (c) 1997-2020 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 auth.c
 * \brief Implementation of DNS and ident lookups.
 * \version $Id$
 */

/*
 * Changes:
 *   July 6, 1999 - Rewrote most of the code here. When a client connects
 *     to the server and passes initial socket validation checks, it
 *     is owned by this module (auth) which returns it to the rest of the
 *     server when dns and auth queries are finished. Until the client is
 *     released, the server does not know it exists and does not process
 *     any messages from it.
 *     --Bleep  Thomas Helvey <tomh@inxpress.net>
 */

#include "stdinc.h"
#include "list.h"
#include "ircd_defs.h"
#include "fdlist.h"
#include "auth.h"
#include "conf.h"
#include "client.h"
#include "event.h"
#include "irc_string.h"
#include "ircd.h"
#include "packet.h"
#include "res.h"
#include "s_bsd.h"
#include "log.h"
#include "send.h"
#include "memory.h"
#include "misc.h"
#include "hostmask.h"


enum
{
  REPORT_DO_DNS,
  REPORT_FIN_DNS,
  REPORT_FAIL_DNS,
  REPORT_DO_ID,
  REPORT_FIN_ID,
  REPORT_FAIL_ID,
  REPORT_IP_MISMATCH,
  REPORT_HOST_TOOLONG,
  REPORT_HOST_INVALID
};

static const char *const HeaderMessages[] =
{
  [REPORT_DO_DNS] = ":*** Looking up your hostname",
  [REPORT_FIN_DNS] = ":*** Found your hostname",
  [REPORT_FAIL_DNS] = ":*** Couldn't look up your hostname",
  [REPORT_DO_ID] = ":*** Checking Ident",
  [REPORT_FIN_ID] = ":*** Got Ident response",
  [REPORT_FAIL_ID] = ":*** No Ident response",
  [REPORT_IP_MISMATCH] = ":*** Your forward and reverse DNS do not match, ignoring hostname",
  [REPORT_HOST_TOOLONG] = ":*** Your hostname is too long, ignoring hostname",
  [REPORT_HOST_INVALID] = ":*** Your hostname contains illegal characters, ignoring hostname"
};

#define auth_sendheader(c, i) sendto_one_notice((c), &me, "%s", HeaderMessages[(i)])


/*! \brief Allocate a new auth request.
 * \param client The client being looked up.
 * \return The newly allocated auth request.
 */
static struct AuthRequest *
auth_make(struct Client *client)
{
  struct AuthRequest *auth = xcalloc(sizeof(*auth));

  auth->client = client;
  auth->client->connection->auth = auth;

  return auth;
}

/*! \brief Free memory
 * \param auth The allocated auth request to cleanup.
 */
static void
auth_free(struct AuthRequest *auth)
{
  auth->client = NULL;
  xfree(auth);
}

/*! \brief Release auth client from auth system. This adds the client into the
 *         local client lists so it can be read by the main io processing loop.
 * \param auth Pointer to AuthRequest struct to release
 */
static void
auth_release_client(struct AuthRequest *auth)
{
  struct Client *client = auth->client;

  assert(client);
  assert(client->connection);

  if (auth->ident_pending == true || auth->dns_pending == true)
    return;

  auth_free(auth);
  client->connection->auth = NULL;

  /*
   * When a client has auth'ed, we want to start reading what it sends
   * us. This is what read_packet() does.
   *     -- adrian
   */
  comm_setflush(client->connection->fd, 1, flood_recalc, client);

  client->connection->last_ping = event_base->time.sec_monotonic;
  client->connection->last_data = event_base->time.sec_monotonic;
  client->connection->created_real = event_base->time.sec_real;
  client->connection->created_monotonic = event_base->time.sec_monotonic;

  AddFlag(client, FLAGS_FINISHED_AUTH);

  read_packet(client->connection->fd, client);
}

/*! Checks if a hostname is valid and doesn't contain illegal characters
 * \param hostname The string to verify
 * \return 1 if it is valid, 0 if it isn't
 */
static bool
auth_verify_hostname(const char *hostname)
{
  const char *p = hostname;

  assert(p);

  if (EmptyString(p) || *p == '.' || *p == ':')
    return false;

  for (; *p; ++p)
    if (!IsHostChar(*p))
      return false;

  return true;
}

/*! \brief Handle a complete DNS lookup. Send the client on its way to a connection
 *         completion, regardless of success or failure.
 * \param vptr The pending struct AuthRequest.
 * \param addr IP address being resolved.
 * \param name Resolved name, or NULL if lookup failed.
 * \param namelength String length of the resolved hostname pointed by 'name'
 */
static void
auth_dns_callback(void *vptr, const struct irc_ssaddr *addr, const char *name, size_t namelength)
{
  struct AuthRequest *const auth = vptr;

  assert(auth->client);
  assert(auth->client->connection);

  auth->dns_pending = false;

  if (namelength == 0)
    auth_sendheader(auth->client, REPORT_FAIL_DNS);
  else if (address_compare(addr, &auth->client->ip, true, false, 0) == false)
    auth_sendheader(auth->client, REPORT_IP_MISMATCH);
  else if (namelength > HOSTLEN)
    auth_sendheader(auth->client, REPORT_HOST_TOOLONG);
  else if (auth_verify_hostname(name) == false)
    auth_sendheader(auth->client, REPORT_HOST_INVALID);
  else
  {
    strlcpy(auth->client->host, name, sizeof(auth->client->host));
    auth_sendheader(auth->client, REPORT_FIN_DNS);
  }

  auth_release_client(auth);
}

/*
 * auth_error - handle auth send errors
 */
static void
auth_error(struct AuthRequest *auth)
{
  assert(auth);
  assert(auth->fd);
  assert(auth->client);
  assert(auth->client->connection);

  ++ServerStats.is_abad;

  fd_close(auth->fd);
  auth->fd = NULL;
  auth->ident_pending = false;

  auth_sendheader(auth->client, REPORT_FAIL_ID);

  auth_release_client(auth);
}

/** Enum used to index ident reply fields in a human-readable way. */
enum IdentReplyFields
{
  IDENT_PORT_NUMBERS,
  IDENT_REPLY_TYPE,
  IDENT_OS_TYPE,
  IDENT_INFO,
  USERID_TOKEN_COUNT
};

/** Parse an ident reply line and extract the userid from it.
 * \param reply The ident reply line.
 * \return The userid, or NULL on parse failure.
 */
static const char *
auth_check_ident_reply(char *const reply)
{
  char *token = NULL, *end = NULL;
  char *vector[USERID_TOKEN_COUNT];
  const unsigned int count = token_vector(reply, ':', vector, USERID_TOKEN_COUNT);

  if (USERID_TOKEN_COUNT != count)
    return NULL;

  /*
   * Second token is the reply type
   */
  token = vector[IDENT_REPLY_TYPE];

  if (EmptyString(token))
    return NULL;

  while (IsSpace(*token))
    ++token;

  if (strncmp(token, "USERID", 6))
    return NULL;

  /*
   * Third token is the os type
   */
  token = vector[IDENT_OS_TYPE];

  if (EmptyString(token))
    return NULL;

  while (IsSpace(*token))
   ++token;

  /*
   * Unless "OTHER" is specified as the operating system type, the server
   * is expected to return the "normal" user identification of the owner
   * of this connection. "Normal" in this context may be taken to mean a
   * string of characters which uniquely identifies the connection owner
   * such as a user identifier assigned by the system administrator and
   * used by such user as a mail identifier, or as the "user" part of a
   * user/password pair used to gain access to system resources. When an
   * operating system is specified (e.g., anything but "OTHER"), the user
   * identifier is expected to be in a more or less immediately useful
   * form - e.g., something that could be used as an argument to "finger"
   * or as a mail address.
   */
  if (strncmp(token, "OTHER", 5) == 0)
    return NULL;

  /*
   * Fourth token is the username
   */
  token = vector[IDENT_INFO];

  if (EmptyString(token))
    return NULL;

  while (IsSpace(*token))
    ++token;

  while (*token == '~' || *token == '^')
    ++token;

  /*
   * Look for the end of the username, terminators are '\0, @, <SPACE>, :'
   */
  for (end = token; *end; ++end)
    if (IsSpace(*end) || '@' == *end || ':' == *end)
      break;
  *end = '\0';

  return token;
}

/*! \brief Read the reply (if any) from the ident server we connected to. We
 *         only give it one shot, if the reply isn't good the first time fail
 *         the authentication entirely. --Bleep
 * \param F The socket/fd to read from.
 * \param data The request to read.
 */
static void
auth_read_reply(fde_t *F, void *data)
{
  struct AuthRequest *const auth = data;
  const char *username = NULL;
  ssize_t len = 0;
  char buf[RFC1413_BUFSIZ + 1];

  assert(auth->fd == F);
  assert(auth->client);
  assert(auth->client->connection);

  if (F->read_handler == NULL && (len = recv(auth->fd->fd, buf, sizeof(buf) - 1, 0)) > 0)
  {
    buf[len] = '\0';
    username = auth_check_ident_reply(buf);
  }

  fd_close(auth->fd);
  auth->fd = NULL;
  auth->ident_pending = false;

  if (EmptyString(username))
  {
    auth_sendheader(auth->client, REPORT_FAIL_ID);
    ++ServerStats.is_abad;
  }
  else
  {
    strlcpy(auth->client->username, username, sizeof(auth->client->username));
    auth_sendheader(auth->client, REPORT_FIN_ID);
    ++ServerStats.is_asuc;
    AddFlag(auth->client, FLAGS_GOTID);
  }

  auth_release_client(auth);
}

/*
 * auth_connect_callback() - deal with the result of comm_connect_tcp()
 *
 * If the connection failed, we simply close the auth fd and report
 * a failure. If the connection suceeded send the ident server a query
 * giving "theirport , ourport". The write is only attempted *once* so
 * it is deemed to be a fail if the entire write doesn't write all the
 * data given.  This shouldnt be a problem since the socket should have
 * a write buffer far greater than this message to store it in should
 * problems arise. -avalon
 */
static void
auth_connect_callback(fde_t *F, int error, void *data)
{
  struct AuthRequest *const auth = data;
  struct irc_ssaddr us;
  struct irc_ssaddr them;
  char authbuf[16];
  ssize_t len = 0;
  socklen_t ulen = sizeof(struct irc_ssaddr);
  socklen_t tlen = sizeof(struct irc_ssaddr);
  uint16_t uport, tport;
  struct sockaddr_in6 *v6;

  assert(auth->fd == F);
  assert(auth->client);
  assert(auth->client->connection);

  if (error != COMM_OK)
  {
    auth_error(auth);
    return;
  }

  if (getsockname(auth->client->connection->fd->fd, (struct sockaddr *)&us, &ulen) ||
      getpeername(auth->client->connection->fd->fd, (struct sockaddr *)&them, &tlen))
  {
    report_error(L_ALL, "auth get{sock,peer}name error %s:%s",
                 client_get_name(auth->client, SHOW_IP), errno);
    auth_error(auth);
    return;
  }

  v6 = (struct sockaddr_in6 *)&us;
  uport = ntohs(v6->sin6_port);
  v6 = (struct sockaddr_in6 *)&them;
  tport = ntohs(v6->sin6_port);

  len = snprintf(authbuf, sizeof(authbuf), "%u, %u\r\n", tport, uport);

  if (send(F->fd, authbuf, len, 0) != len)
  {
    auth_error(auth);
    return;
  }

  comm_setselect(F, COMM_SELECT_READ, auth_read_reply, auth, 4);
}

/*! \brief Flag the client to show an attempt to contact the ident server on
 *         the client's host. Should the connect or any later phase of the
 *         identifying process fail, it is aborted and the user is given a
 *         username of "unknown".
 * \param auth The request for which to start the ident lookup.
 */
static void
auth_start_query(struct AuthRequest *auth)
{
  struct irc_ssaddr localaddr;
  socklen_t locallen = sizeof(struct irc_ssaddr);
  struct sockaddr_in6 *v6;

  assert(auth->client);
  assert(auth->client->connection);

  /* Open a socket of the same type as the client socket */
  int fd = comm_socket(auth->client->ip.ss.ss_family, SOCK_STREAM, 0);
  if (fd == -1)
  {
    report_error(L_ALL, "creating auth stream socket %s:%s",
                 client_get_name(auth->client, SHOW_IP), errno);
    ++ServerStats.is_abad;
    return;
  }

  auth->fd = fd_open(fd, true, "ident");
  auth->ident_pending = true;

  auth_sendheader(auth->client, REPORT_DO_ID);

  /*
   * Get the local address of the client and bind to that to
   * make the auth request.
   */
  memset(&localaddr, 0, locallen);
  getsockname(auth->client->connection->fd->fd, (struct sockaddr *)&localaddr, &locallen);

  remove_ipv6_mapping(&localaddr);
  v6 = (struct sockaddr_in6 *)&localaddr;
  v6->sin6_port = htons(0);

  comm_connect_tcp(auth->fd, &auth->client->ip, RFC1413_PORT, &localaddr,
                   auth_connect_callback, auth, 4);
}

/*
 * auth_start
 *
 * inputs       - pointer to client to auth
 * output       - NONE
 * side effects - starts auth (identd) and dns queries for a client
 */
void
auth_start(struct Client *client)
{
  struct AuthRequest *auth = auth_make(client);

  assert(client);
  assert(client->connection);

  auth_sendheader(client, REPORT_DO_DNS);

  auth->dns_pending = true;

  if (ConfigGeneral.disable_auth == 0)
    auth_start_query(auth);

  gethost_byaddr(auth_dns_callback, auth, &client->ip);
}

/*
 * auth_delete()
 */
void
auth_delete(struct AuthRequest *auth)
{
  assert(auth->client);
  assert(auth->client->connection);

  if (auth->fd)
  {
    fd_close(auth->fd);
    auth->fd = NULL;
  }

  auth->ident_pending = false;

  delete_resolver_queries(auth);
  auth->dns_pending = false;

  auth_free(auth);
}
Revision:	9596
Committed:	Fri Sep 4 16:51:08 2020 UTC (4 years, 11 months ago) by michael
Content type:	text/x-csrc
File size:	13621 byte(s)
Log Message:	- Cleanup ip address matching routine in various places
#	Content
1	/*
2	* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3	*
4	* Copyright (c) 1997-2020 ircd-hybrid development team
5	*
6	* This program is free software; you can redistribute it and/or modify
7	* it under the terms of the GNU General Public License as published by
8	* the Free Software Foundation; either version 2 of the License, or
9	* (at your option) any later version.
10	*
11	* This program is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the GNU General Public License
17	* along with this program; if not, write to the Free Software
18	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
19	* USA
20	*/
21
22	/*! \file auth.c
23	* \brief Implementation of DNS and ident lookups.
24	* \version $Id$
25	*/
26
27	/*
28	* Changes:
29	* July 6, 1999 - Rewrote most of the code here. When a client connects
30	* to the server and passes initial socket validation checks, it
31	* is owned by this module (auth) which returns it to the rest of the
32	* server when dns and auth queries are finished. Until the client is
33	* released, the server does not know it exists and does not process
34	* any messages from it.
35	* --Bleep Thomas Helvey <tomh@inxpress.net>
36	*/
37
38	#include "stdinc.h"
39	#include "list.h"
40	#include "ircd_defs.h"
41	#include "fdlist.h"
42	#include "auth.h"
43	#include "conf.h"
44	#include "client.h"
45	#include "event.h"
46	#include "irc_string.h"
47	#include "ircd.h"
48	#include "packet.h"
49	#include "res.h"
50	#include "s_bsd.h"
51	#include "log.h"
52	#include "send.h"
53	#include "memory.h"
54	#include "misc.h"
55	#include "hostmask.h"
56
57
58	enum
59	{
60	REPORT_DO_DNS,
61	REPORT_FIN_DNS,
62	REPORT_FAIL_DNS,
63	REPORT_DO_ID,
64	REPORT_FIN_ID,
65	REPORT_FAIL_ID,
66	REPORT_IP_MISMATCH,
67	REPORT_HOST_TOOLONG,
68	REPORT_HOST_INVALID
69	};
70
71	static const char *const HeaderMessages[] =
72	{
73	[REPORT_DO_DNS] = ":*** Looking up your hostname",
74	[REPORT_FIN_DNS] = ":*** Found your hostname",
75	[REPORT_FAIL_DNS] = ":*** Couldn't look up your hostname",
76	[REPORT_DO_ID] = ":*** Checking Ident",
77	[REPORT_FIN_ID] = ":*** Got Ident response",
78	[REPORT_FAIL_ID] = ":*** No Ident response",
79	[REPORT_IP_MISMATCH] = ":*** Your forward and reverse DNS do not match, ignoring hostname",
80	[REPORT_HOST_TOOLONG] = ":*** Your hostname is too long, ignoring hostname",
81	[REPORT_HOST_INVALID] = ":*** Your hostname contains illegal characters, ignoring hostname"
82	};
83
84	#define auth_sendheader(c, i) sendto_one_notice((c), &me, "%s", HeaderMessages[(i)])
85
86
87
88	/*! \brief Allocate a new auth request.
89	* \param client The client being looked up.
90	* \return The newly allocated auth request.
91	*/
92	static struct AuthRequest *
93	auth_make(struct Client *client)
94	{
95	struct AuthRequest auth = xcalloc(sizeof(auth));
96
97	auth->client = client;
98	auth->client->connection->auth = auth;
99
100	return auth;
101	}
102
103	/*! \brief Free memory
104	* \param auth The allocated auth request to cleanup.
105	*/
106	static void
107	auth_free(struct AuthRequest *auth)
108	{
109	auth->client = NULL;
110	xfree(auth);
111	}
112
113	/*! \brief Release auth client from auth system. This adds the client into the
114	* local client lists so it can be read by the main io processing loop.
115	* \param auth Pointer to AuthRequest struct to release
116	*/
117	static void
118	auth_release_client(struct AuthRequest *auth)
119	{
120	struct Client *client = auth->client;
121
122	assert(client);
123	assert(client->connection);
124
125	if (auth->ident_pending == true \|\| auth->dns_pending == true)
126	return;
127
128	auth_free(auth);
129	client->connection->auth = NULL;
130
131	/*
132	* When a client has auth'ed, we want to start reading what it sends
133	* us. This is what read_packet() does.
134	* -- adrian
135	*/
136	comm_setflush(client->connection->fd, 1, flood_recalc, client);
137
138	client->connection->last_ping = event_base->time.sec_monotonic;
139	client->connection->last_data = event_base->time.sec_monotonic;
140	client->connection->created_real = event_base->time.sec_real;
141	client->connection->created_monotonic = event_base->time.sec_monotonic;
142
143	AddFlag(client, FLAGS_FINISHED_AUTH);
144
145	read_packet(client->connection->fd, client);
146	}
147
148	/*! Checks if a hostname is valid and doesn't contain illegal characters
149	* \param hostname The string to verify
150	* \return 1 if it is valid, 0 if it isn't
151	*/
152	static bool
153	auth_verify_hostname(const char *hostname)
154	{
155	const char *p = hostname;
156
157	assert(p);
158
159	if (EmptyString(p) \|\| p == '.' \|\| p == ':')
160	return false;
161
162	for (; *p; ++p)
163	if (!IsHostChar(*p))
164	return false;
165
166	return true;
167	}
168
169	/*! \brief Handle a complete DNS lookup. Send the client on its way to a connection
170	* completion, regardless of success or failure.
171	* \param vptr The pending struct AuthRequest.
172	* \param addr IP address being resolved.
173	* \param name Resolved name, or NULL if lookup failed.
174	* \param namelength String length of the resolved hostname pointed by 'name'
175	*/
176	static void
177	auth_dns_callback(void vptr, const struct irc_ssaddr addr, const char *name, size_t namelength)
178	{
179	struct AuthRequest *const auth = vptr;
180
181	assert(auth->client);
182	assert(auth->client->connection);
183
184	auth->dns_pending = false;
185
186	if (namelength == 0)
187	auth_sendheader(auth->client, REPORT_FAIL_DNS);
188	else if (address_compare(addr, &auth->client->ip, true, false, 0) == false)
189	auth_sendheader(auth->client, REPORT_IP_MISMATCH);
190	else if (namelength > HOSTLEN)
191	auth_sendheader(auth->client, REPORT_HOST_TOOLONG);
192	else if (auth_verify_hostname(name) == false)
193	auth_sendheader(auth->client, REPORT_HOST_INVALID);
194	else
195	{
196	strlcpy(auth->client->host, name, sizeof(auth->client->host));
197	auth_sendheader(auth->client, REPORT_FIN_DNS);
198	}
199
200	auth_release_client(auth);
201	}
202
203	/*
204	* auth_error - handle auth send errors
205	*/
206	static void
207	auth_error(struct AuthRequest *auth)
208	{
209	assert(auth);
210	assert(auth->fd);
211	assert(auth->client);
212	assert(auth->client->connection);
213
214	++ServerStats.is_abad;
215
216	fd_close(auth->fd);
217	auth->fd = NULL;
218	auth->ident_pending = false;
219
220	auth_sendheader(auth->client, REPORT_FAIL_ID);
221
222	auth_release_client(auth);
223	}
224
225	/** Enum used to index ident reply fields in a human-readable way. */
226	enum IdentReplyFields
227	{
228	IDENT_PORT_NUMBERS,
229	IDENT_REPLY_TYPE,
230	IDENT_OS_TYPE,
231	IDENT_INFO,
232	USERID_TOKEN_COUNT
233	};
234
235	/** Parse an ident reply line and extract the userid from it.
236	* \param reply The ident reply line.
237	* \return The userid, or NULL on parse failure.
238	*/
239	static const char *
240	auth_check_ident_reply(char *const reply)
241	{
242	char token = NULL, end = NULL;
243	char *vector[USERID_TOKEN_COUNT];
244	const unsigned int count = token_vector(reply, ':', vector, USERID_TOKEN_COUNT);
245
246	if (USERID_TOKEN_COUNT != count)
247	return NULL;
248
249	/*
250	* Second token is the reply type
251	*/
252	token = vector[IDENT_REPLY_TYPE];
253
254	if (EmptyString(token))
255	return NULL;
256
257	while (IsSpace(*token))
258	++token;
259
260	if (strncmp(token, "USERID", 6))
261	return NULL;
262
263	/*
264	* Third token is the os type
265	*/
266	token = vector[IDENT_OS_TYPE];
267
268	if (EmptyString(token))
269	return NULL;
270
271	while (IsSpace(*token))
272	++token;
273
274	/*
275	* Unless "OTHER" is specified as the operating system type, the server
276	* is expected to return the "normal" user identification of the owner
277	* of this connection. "Normal" in this context may be taken to mean a
278	* string of characters which uniquely identifies the connection owner
279	* such as a user identifier assigned by the system administrator and
280	* used by such user as a mail identifier, or as the "user" part of a
281	* user/password pair used to gain access to system resources. When an
282	* operating system is specified (e.g., anything but "OTHER"), the user
283	* identifier is expected to be in a more or less immediately useful
284	* form - e.g., something that could be used as an argument to "finger"
285	* or as a mail address.
286	*/
287	if (strncmp(token, "OTHER", 5) == 0)
288	return NULL;
289
290	/*
291	* Fourth token is the username
292	*/
293	token = vector[IDENT_INFO];
294
295	if (EmptyString(token))
296	return NULL;
297
298	while (IsSpace(*token))
299	++token;
300
301	while (token == '~' \|\| token == '^')
302	++token;
303
304	/*
305	* Look for the end of the username, terminators are '\0, @, <SPACE>, :'
306	*/
307	for (end = token; *end; ++end)
308	if (IsSpace(end) \|\| '@' == end \|\| ':' == *end)
309	break;
310	*end = '\0';
311
312	return token;
313	}
314
315	/*! \brief Read the reply (if any) from the ident server we connected to. We
316	* only give it one shot, if the reply isn't good the first time fail
317	* the authentication entirely. --Bleep
318	* \param F The socket/fd to read from.
319	* \param data The request to read.
320	*/
321	static void
322	auth_read_reply(fde_t F, void data)
323	{
324	struct AuthRequest *const auth = data;
325	const char *username = NULL;
326	ssize_t len = 0;
327	char buf[RFC1413_BUFSIZ + 1];
328
329	assert(auth->fd == F);
330	assert(auth->client);
331	assert(auth->client->connection);
332
333	if (F->read_handler == NULL && (len = recv(auth->fd->fd, buf, sizeof(buf) - 1, 0)) > 0)
334	{
335	buf[len] = '\0';
336	username = auth_check_ident_reply(buf);
337	}
338
339	fd_close(auth->fd);
340	auth->fd = NULL;
341	auth->ident_pending = false;
342
343	if (EmptyString(username))
344	{
345	auth_sendheader(auth->client, REPORT_FAIL_ID);
346	++ServerStats.is_abad;
347	}
348	else
349	{
350	strlcpy(auth->client->username, username, sizeof(auth->client->username));
351	auth_sendheader(auth->client, REPORT_FIN_ID);
352	++ServerStats.is_asuc;
353	AddFlag(auth->client, FLAGS_GOTID);
354	}
355
356	auth_release_client(auth);
357	}
358
359	/*
360	* auth_connect_callback() - deal with the result of comm_connect_tcp()
361	*
362	* If the connection failed, we simply close the auth fd and report
363	* a failure. If the connection suceeded send the ident server a query
364	* giving "theirport , ourport". The write is only attempted once so
365	* it is deemed to be a fail if the entire write doesn't write all the
366	* data given. This shouldnt be a problem since the socket should have
367	* a write buffer far greater than this message to store it in should
368	* problems arise. -avalon
369	*/
370	static void
371	auth_connect_callback(fde_t F, int error, void data)
372	{
373	struct AuthRequest *const auth = data;
374	struct irc_ssaddr us;
375	struct irc_ssaddr them;
376	char authbuf[16];
377	ssize_t len = 0;
378	socklen_t ulen = sizeof(struct irc_ssaddr);
379	socklen_t tlen = sizeof(struct irc_ssaddr);
380	uint16_t uport, tport;
381	struct sockaddr_in6 *v6;
382
383	assert(auth->fd == F);
384	assert(auth->client);
385	assert(auth->client->connection);
386
387	if (error != COMM_OK)
388	{
389	auth_error(auth);
390	return;
391	}
392
393	if (getsockname(auth->client->connection->fd->fd, (struct sockaddr *)&us, &ulen) \|\|
394	getpeername(auth->client->connection->fd->fd, (struct sockaddr *)&them, &tlen))
395	{
396	report_error(L_ALL, "auth get{sock,peer}name error %s:%s",
397	client_get_name(auth->client, SHOW_IP), errno);
398	auth_error(auth);
399	return;
400	}
401
402	v6 = (struct sockaddr_in6 *)&us;
403	uport = ntohs(v6->sin6_port);
404	v6 = (struct sockaddr_in6 *)&them;
405	tport = ntohs(v6->sin6_port);
406
407	len = snprintf(authbuf, sizeof(authbuf), "%u, %u\r\n", tport, uport);
408
409	if (send(F->fd, authbuf, len, 0) != len)
410	{
411	auth_error(auth);
412	return;
413	}
414
415	comm_setselect(F, COMM_SELECT_READ, auth_read_reply, auth, 4);
416	}
417
418	/*! \brief Flag the client to show an attempt to contact the ident server on
419	* the client's host. Should the connect or any later phase of the
420	* identifying process fail, it is aborted and the user is given a
421	* username of "unknown".
422	* \param auth The request for which to start the ident lookup.
423	*/
424	static void
425	auth_start_query(struct AuthRequest *auth)
426	{
427	struct irc_ssaddr localaddr;
428	socklen_t locallen = sizeof(struct irc_ssaddr);
429	struct sockaddr_in6 *v6;
430
431	assert(auth->client);
432	assert(auth->client->connection);
433
434	/* Open a socket of the same type as the client socket */
435	int fd = comm_socket(auth->client->ip.ss.ss_family, SOCK_STREAM, 0);
436	if (fd == -1)
437	{
438	report_error(L_ALL, "creating auth stream socket %s:%s",
439	client_get_name(auth->client, SHOW_IP), errno);
440	++ServerStats.is_abad;
441	return;
442	}
443
444	auth->fd = fd_open(fd, true, "ident");
445	auth->ident_pending = true;
446
447	auth_sendheader(auth->client, REPORT_DO_ID);
448
449	/*
450	* Get the local address of the client and bind to that to
451	* make the auth request.
452	*/
453	memset(&localaddr, 0, locallen);
454	getsockname(auth->client->connection->fd->fd, (struct sockaddr *)&localaddr, &locallen);
455
456	remove_ipv6_mapping(&localaddr);
457	v6 = (struct sockaddr_in6 *)&localaddr;
458	v6->sin6_port = htons(0);
459
460	comm_connect_tcp(auth->fd, &auth->client->ip, RFC1413_PORT, &localaddr,
461	auth_connect_callback, auth, 4);
462	}
463
464	/*
465	* auth_start
466	*
467	* inputs - pointer to client to auth
468	* output - NONE
469	* side effects - starts auth (identd) and dns queries for a client
470	*/
471	void
472	auth_start(struct Client *client)
473	{
474	struct AuthRequest *auth = auth_make(client);
475
476	assert(client);
477	assert(client->connection);
478
479	auth_sendheader(client, REPORT_DO_DNS);
480
481	auth->dns_pending = true;
482
483	if (ConfigGeneral.disable_auth == 0)
484	auth_start_query(auth);
485
486	gethost_byaddr(auth_dns_callback, auth, &client->ip);
487	}
488
489	/*
490	* auth_delete()
491	*/
492	void
493	auth_delete(struct AuthRequest *auth)
494	{
495	assert(auth->client);
496	assert(auth->client->connection);
497
498	if (auth->fd)
499	{
500	fd_close(auth->fd);
501	auth->fd = NULL;
502	}
503
504	auth->ident_pending = false;
505
506	delete_resolver_queries(auth);
507	auth->dns_pending = false;
508
509	auth_free(auth);
510	}