8.2.x/src/auth.c

/*
 *  ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
 *
 *  Copyright (c) 1997-2016 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 auth.c
 * \brief Functions for querying a users ident.
 * \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 "mempool.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
};

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"
};

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

static dlink_list auth_list;
static void read_auth_reply(fde_t *, void *);
static void auth_connect_callback(fde_t *, int, void *);


/*
 * make_auth_request - allocate a new auth request
 */
static struct AuthRequest *
make_auth_request(struct Client *client)
{
  struct AuthRequest *const auth = &client->connection->auth;

  memset(auth, 0, sizeof(*auth));

  auth->client = client;
  auth->timeout = CurrentTime + CONNECTTIMEOUT;

  return auth;
}

/*
 * release_auth_client - 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
 */
void
release_auth_client(struct AuthRequest *auth)
{
  struct Client *const client = auth->client;

  if (IsDoingAuth(auth) || IsDNSPending(auth))
    return;

  if (IsInAuth(auth))
  {
    dlinkDelete(&auth->node, &auth_list);
    ClearInAuth(auth);
  }

  /*
   * When a client has auth'ed, we want to start reading what it sends
   * us. This is what read_packet() does.
   *     -- adrian
   */
  client->connection->allow_read = MAX_FLOOD;
  comm_setflush(&client->connection->fd, 1000, flood_recalc, client);

  client->connection->since     = CurrentTime;
  client->connection->lasttime  = CurrentTime;
  client->connection->firsttime = CurrentTime;
  client->flags |= FLAGS_FINISHED_AUTH;

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

/*
 * auth_dns_callback - called when resolver query finishes
 * if the query resulted in a successful search, name will contain
 * a non-NULL pointer, otherwise name will be NULL.
 * set the client on it's way to a connection completion, regardless
 * of success of failure
 */
static void
auth_dns_callback(void *vptr, const struct irc_ssaddr *addr, const char *name, size_t namelength)
{
  struct AuthRequest *const auth = vptr;

  ClearDNSPending(auth);

  if (!EmptyString(name))
  {
    if (auth->client->connection->ip.ss.ss_family == AF_INET6)
    {
      const struct sockaddr_in6 *const v6 = (const struct sockaddr_in6 *)&auth->client->connection->ip;
      const struct sockaddr_in6 *const v6dns = (const struct sockaddr_in6 *)addr;

      if (memcmp(&v6->sin6_addr, &v6dns->sin6_addr, sizeof(struct in6_addr)))
      {
        sendheader(auth->client, REPORT_IP_MISMATCH);
        release_auth_client(auth);
        return;
      }
    }
    else
    {
      const struct sockaddr_in *const v4 = (const struct sockaddr_in *)&auth->client->connection->ip;
      const struct sockaddr_in *const v4dns = (const struct sockaddr_in *)addr;

      if (v4->sin_addr.s_addr != v4dns->sin_addr.s_addr)
      {
        sendheader(auth->client, REPORT_IP_MISMATCH);
        release_auth_client(auth);
        return;
      }
    }

    if (namelength > HOSTLEN)
      sendheader(auth->client, REPORT_HOST_TOOLONG);
    else
    {
      strlcpy(auth->client->host, name, sizeof(auth->client->host));
      sendheader(auth->client, REPORT_FIN_DNS);
    }
  }
  else
    sendheader(auth->client, REPORT_FAIL_DNS);

  release_auth_client(auth);
}

/*
 * authsenderr - handle auth send errors
 */
static void
auth_error(struct AuthRequest *auth)
{
  ++ServerStats.is_abad;

  fd_close(&auth->fd);

  ClearAuth(auth);

  sendheader(auth->client, REPORT_FAIL_ID);

  release_auth_client(auth);
}

/*
 * start_auth_query - Flag the client to show that an attempt to
 * contact the ident server on
 * the client's host.  The connect and subsequently the socket are all put
 * into 'non-blocking' mode.  Should the connect or any later phase of the
 * identifing process fail, it is aborted and the user is given a username
 * of "unknown".
 */
static void
start_auth_query(struct AuthRequest *auth)
{
  struct irc_ssaddr localaddr;
  socklen_t locallen = sizeof(struct irc_ssaddr);
  struct sockaddr_in6 *v6;

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

  SetDoingAuth(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);
  localaddr.ss_port = htons(0);

  comm_connect_tcp(&auth->fd, auth->client->sockhost, RFC1413_PORT,
      (struct sockaddr *)&localaddr, localaddr.ss_len, auth_connect_callback,
      auth, auth->client->connection->ip.ss.ss_family,
      GlobalSetOptions.ident_timeout);
}

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

  SetInAuth(auth);
  dlinkAddTail(auth, &auth->node, &auth_list);

  sendheader(client_p, REPORT_DO_DNS);

  SetDNSPending(auth);

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

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

/*
 * timeout_auth_queries - timeout resolver and identd requests
 * allow clients through if requests failed
 */
static void
timeout_auth_queries_event(void *notused)
{
  dlink_node *node, *node_next;

  DLINK_FOREACH_SAFE(node, node_next, auth_list.head)
  {
    struct AuthRequest *auth = node->data;

    if (auth->timeout > CurrentTime)
      break;

    if (IsDoingAuth(auth))
    {
      ++ServerStats.is_abad;
      fd_close(&auth->fd);
      ClearAuth(auth);
      sendheader(auth->client, REPORT_FAIL_ID);
    }

    if (IsDNSPending(auth))
    {
      delete_resolver_queries(auth);
      ClearDNSPending(auth);
      sendheader(auth->client, REPORT_FAIL_DNS);
    }

    release_auth_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 *fd, 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;

  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",
                 get_client_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(fd->fd, authbuf, len, 0) != len)
  {
    auth_error(auth);
    return;
  }

  comm_setselect(fd, COMM_SELECT_READ, read_auth_reply, auth, 0);
}

/** 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 *
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))
    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;
}

/*
 * read_auth_reply - 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
 */
static void
read_auth_reply(fde_t *fd, void *data)
{
  struct AuthRequest *const auth = data;
  const char *username = NULL;
  ssize_t len = 0;
  char buf[RFC1413_BUFSIZ + 1];

  if ((len = recv(fd->fd, buf, RFC1413_BUFSIZ, 0)) > 0)
  {
    buf[len] = '\0';
    username = check_ident_reply(buf);
  }

  fd_close(fd);

  ClearAuth(auth);

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

  release_auth_client(auth);
}

/*
 * delete_auth()
 */
void
delete_auth(struct AuthRequest *auth)
{
  if (IsDNSPending(auth))
    delete_resolver_queries(auth);

  if (IsDoingAuth(auth))
    fd_close(&auth->fd);

  if (IsInAuth(auth))
  {
    dlinkDelete(&auth->node, &auth_list);
    ClearInAuth(auth);
  }
}

/* auth_init
 *
 * Initialise the auth code
 */
void
auth_init(void)
{
  static struct event timeout_auth_queries =
  {
    .name = "timeout_auth_queries_event",
    .handler = timeout_auth_queries_event,
    .when = 1
  };

  event_add(&timeout_auth_queries, NULL);
}
Revision:	7913
Committed:	Sun Nov 27 18:54:38 2016 UTC (7 years, 4 months ago) by michael
Content type:	text/x-csrc
File size:	13895 byte(s)
Log Message:	- Style corrections
#	Content
1	/*
2	* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3	*
4	* Copyright (c) 1997-2016 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 Functions for querying a users ident.
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 "mempool.h"
54
55
56	enum
57	{
58	REPORT_DO_DNS,
59	REPORT_FIN_DNS,
60	REPORT_FAIL_DNS,
61	REPORT_DO_ID,
62	REPORT_FIN_ID,
63	REPORT_FAIL_ID,
64	REPORT_IP_MISMATCH,
65	REPORT_HOST_TOOLONG
66	};
67
68	static const char *const HeaderMessages[] =
69	{
70	[REPORT_DO_DNS] = ":*** Looking up your hostname",
71	[REPORT_FIN_DNS] = ":*** Found your hostname",
72	[REPORT_FAIL_DNS] = ":*** Couldn't look up your hostname",
73	[REPORT_DO_ID] = ":*** Checking Ident",
74	[REPORT_FIN_ID] = ":*** Got Ident response",
75	[REPORT_FAIL_ID] = ":*** No Ident response",
76	[REPORT_IP_MISMATCH] = ":*** Your forward and reverse DNS do not match, ignoring hostname",
77	[REPORT_HOST_TOOLONG] = ":*** Your hostname is too long, ignoring hostname"
78	};
79
80	#define sendheader(c, i) sendto_one_notice((c), &me, "%s", HeaderMessages[(i)])
81
82	static dlink_list auth_list;
83	static void read_auth_reply(fde_t , void );
84	static void auth_connect_callback(fde_t , int, void );
85
86
87	/*
88	* make_auth_request - allocate a new auth request
89	*/
90	static struct AuthRequest *
91	make_auth_request(struct Client *client)
92	{
93	struct AuthRequest *const auth = &client->connection->auth;
94
95	memset(auth, 0, sizeof(*auth));
96
97	auth->client = client;
98	auth->timeout = CurrentTime + CONNECTTIMEOUT;
99
100	return auth;
101	}
102
103	/*
104	* release_auth_client - release auth client from auth system
105	* this adds the client into the local client lists so it can be read by
106	* the main io processing loop
107	*/
108	void
109	release_auth_client(struct AuthRequest *auth)
110	{
111	struct Client *const client = auth->client;
112
113	if (IsDoingAuth(auth) \|\| IsDNSPending(auth))
114	return;
115
116	if (IsInAuth(auth))
117	{
118	dlinkDelete(&auth->node, &auth_list);
119	ClearInAuth(auth);
120	}
121
122	/*
123	* When a client has auth'ed, we want to start reading what it sends
124	* us. This is what read_packet() does.
125	* -- adrian
126	*/
127	client->connection->allow_read = MAX_FLOOD;
128	comm_setflush(&client->connection->fd, 1000, flood_recalc, client);
129
130	client->connection->since = CurrentTime;
131	client->connection->lasttime = CurrentTime;
132	client->connection->firsttime = CurrentTime;
133	client->flags \|= FLAGS_FINISHED_AUTH;
134
135	read_packet(&client->connection->fd, client);
136	}
137
138	/*
139	* auth_dns_callback - called when resolver query finishes
140	* if the query resulted in a successful search, name will contain
141	* a non-NULL pointer, otherwise name will be NULL.
142	* set the client on it's way to a connection completion, regardless
143	* of success of failure
144	*/
145	static void
146	auth_dns_callback(void vptr, const struct irc_ssaddr addr, const char *name, size_t namelength)
147	{
148	struct AuthRequest *const auth = vptr;
149
150	ClearDNSPending(auth);
151
152	if (!EmptyString(name))
153	{
154	if (auth->client->connection->ip.ss.ss_family == AF_INET6)
155	{
156	const struct sockaddr_in6 const v6 = (const struct sockaddr_in6 )&auth->client->connection->ip;
157	const struct sockaddr_in6 const v6dns = (const struct sockaddr_in6 )addr;
158
159	if (memcmp(&v6->sin6_addr, &v6dns->sin6_addr, sizeof(struct in6_addr)))
160	{
161	sendheader(auth->client, REPORT_IP_MISMATCH);
162	release_auth_client(auth);
163	return;
164	}
165	}
166	else
167	{
168	const struct sockaddr_in const v4 = (const struct sockaddr_in )&auth->client->connection->ip;
169	const struct sockaddr_in const v4dns = (const struct sockaddr_in )addr;
170
171	if (v4->sin_addr.s_addr != v4dns->sin_addr.s_addr)
172	{
173	sendheader(auth->client, REPORT_IP_MISMATCH);
174	release_auth_client(auth);
175	return;
176	}
177	}
178
179	if (namelength > HOSTLEN)
180	sendheader(auth->client, REPORT_HOST_TOOLONG);
181	else
182	{
183	strlcpy(auth->client->host, name, sizeof(auth->client->host));
184	sendheader(auth->client, REPORT_FIN_DNS);
185	}
186	}
187	else
188	sendheader(auth->client, REPORT_FAIL_DNS);
189
190	release_auth_client(auth);
191	}
192
193	/*
194	* authsenderr - handle auth send errors
195	*/
196	static void
197	auth_error(struct AuthRequest *auth)
198	{
199	++ServerStats.is_abad;
200
201	fd_close(&auth->fd);
202
203	ClearAuth(auth);
204
205	sendheader(auth->client, REPORT_FAIL_ID);
206
207	release_auth_client(auth);
208	}
209
210	/*
211	* start_auth_query - Flag the client to show that an attempt to
212	* contact the ident server on
213	* the client's host. The connect and subsequently the socket are all put
214	* into 'non-blocking' mode. Should the connect or any later phase of the
215	* identifing process fail, it is aborted and the user is given a username
216	* of "unknown".
217	*/
218	static void
219	start_auth_query(struct AuthRequest *auth)
220	{
221	struct irc_ssaddr localaddr;
222	socklen_t locallen = sizeof(struct irc_ssaddr);
223	struct sockaddr_in6 *v6;
224
225	/* open a socket of the same type as the client socket */
226	if (comm_open(&auth->fd, auth->client->connection->ip.ss.ss_family,
227	SOCK_STREAM, 0, "ident") == -1)
228	{
229	report_error(L_ALL, "creating auth stream socket %s:%s",
230	get_client_name(auth->client, SHOW_IP), errno);
231	++ServerStats.is_abad;
232	return;
233	}
234
235	SetDoingAuth(auth);
236	sendheader(auth->client, REPORT_DO_ID);
237
238	/*
239	* Get the local address of the client and bind to that to
240	* make the auth request.
241	*/
242	memset(&localaddr, 0, locallen);
243	getsockname(auth->client->connection->fd.fd, (struct sockaddr*)&localaddr,
244	&locallen);
245
246	remove_ipv6_mapping(&localaddr);
247	v6 = (struct sockaddr_in6 *)&localaddr;
248	v6->sin6_port = htons(0);
249	localaddr.ss_port = htons(0);
250
251	comm_connect_tcp(&auth->fd, auth->client->sockhost, RFC1413_PORT,
252	(struct sockaddr *)&localaddr, localaddr.ss_len, auth_connect_callback,
253	auth, auth->client->connection->ip.ss.ss_family,
254	GlobalSetOptions.ident_timeout);
255	}
256
257	/*
258	* start_auth
259	*
260	* inputs - pointer to client to auth
261	* output - NONE
262	* side effects - starts auth (identd) and dns queries for a client
263	*/
264	void
265	start_auth(struct Client *client_p)
266	{
267	struct AuthRequest *const auth = make_auth_request(client_p);
268
269	SetInAuth(auth);
270	dlinkAddTail(auth, &auth->node, &auth_list);
271
272	sendheader(client_p, REPORT_DO_DNS);
273
274	SetDNSPending(auth);
275
276	if (ConfigGeneral.disable_auth == 0)
277	start_auth_query(auth);
278
279	gethost_byaddr(auth_dns_callback, auth, &client_p->connection->ip);
280	}
281
282	/*
283	* timeout_auth_queries - timeout resolver and identd requests
284	* allow clients through if requests failed
285	*/
286	static void
287	timeout_auth_queries_event(void *notused)
288	{
289	dlink_node node, node_next;
290
291	DLINK_FOREACH_SAFE(node, node_next, auth_list.head)
292	{
293	struct AuthRequest *auth = node->data;
294
295	if (auth->timeout > CurrentTime)
296	break;
297
298	if (IsDoingAuth(auth))
299	{
300	++ServerStats.is_abad;
301	fd_close(&auth->fd);
302	ClearAuth(auth);
303	sendheader(auth->client, REPORT_FAIL_ID);
304	}
305
306	if (IsDNSPending(auth))
307	{
308	delete_resolver_queries(auth);
309	ClearDNSPending(auth);
310	sendheader(auth->client, REPORT_FAIL_DNS);
311	}
312
313	release_auth_client(auth);
314	}
315	}
316
317	/*
318	* auth_connect_callback() - deal with the result of comm_connect_tcp()
319	*
320	* If the connection failed, we simply close the auth fd and report
321	* a failure. If the connection suceeded send the ident server a query
322	* giving "theirport , ourport". The write is only attempted once so
323	* it is deemed to be a fail if the entire write doesn't write all the
324	* data given. This shouldnt be a problem since the socket should have
325	* a write buffer far greater than this message to store it in should
326	* problems arise. -avalon
327	*/
328	static void
329	auth_connect_callback(fde_t fd, int error, void data)
330	{
331	struct AuthRequest *const auth = data;
332	struct irc_ssaddr us;
333	struct irc_ssaddr them;
334	char authbuf[16];
335	ssize_t len = 0;
336	socklen_t ulen = sizeof(struct irc_ssaddr);
337	socklen_t tlen = sizeof(struct irc_ssaddr);
338	uint16_t uport, tport;
339	struct sockaddr_in6 *v6;
340
341	if (error != COMM_OK)
342	{
343	auth_error(auth);
344	return;
345	}
346
347	if (getsockname(auth->client->connection->fd.fd, (struct sockaddr *)&us, &ulen) \|\|
348	getpeername(auth->client->connection->fd.fd, (struct sockaddr *)&them, &tlen))
349	{
350	report_error(L_ALL, "auth get{sock,peer}name error %s:%s",
351	get_client_name(auth->client, SHOW_IP), errno);
352	auth_error(auth);
353	return;
354	}
355
356	v6 = (struct sockaddr_in6 *)&us;
357	uport = ntohs(v6->sin6_port);
358	v6 = (struct sockaddr_in6 *)&them;
359	tport = ntohs(v6->sin6_port);
360
361	len = snprintf(authbuf, sizeof(authbuf), "%u, %u\r\n", tport, uport);
362
363	if (send(fd->fd, authbuf, len, 0) != len)
364	{
365	auth_error(auth);
366	return;
367	}
368
369	comm_setselect(fd, COMM_SELECT_READ, read_auth_reply, auth, 0);
370	}
371
372	/** Enum used to index ident reply fields in a human-readable way. */
373	enum IdentReplyFields
374	{
375	IDENT_PORT_NUMBERS,
376	IDENT_REPLY_TYPE,
377	IDENT_OS_TYPE,
378	IDENT_INFO,
379	USERID_TOKEN_COUNT
380	};
381
382	/** Parse an ident reply line and extract the userid from it.
383	* \param reply The ident reply line.
384	* \return The userid, or NULL on parse failure.
385	*/
386	static const char *
387	check_ident_reply(char *const reply)
388	{
389	char token = NULL, end = NULL;
390	char *vector[USERID_TOKEN_COUNT];
391	const unsigned int count = token_vector(reply, ':', vector, USERID_TOKEN_COUNT);
392
393	if (USERID_TOKEN_COUNT != count)
394	return NULL;
395
396	/*
397	* Second token is the reply type
398	*/
399	token = vector[IDENT_REPLY_TYPE];
400
401	if (EmptyString(token))
402	return NULL;
403
404	while (IsSpace(*token))
405	++token;
406
407	if (strncmp(token, "USERID", 6))
408	return NULL;
409
410	/*
411	* Third token is the os type
412	*/
413	token = vector[IDENT_OS_TYPE];
414
415	if (EmptyString(token))
416	return NULL;
417
418	while (IsSpace(*token))
419	++token;
420
421	/*
422	* Unless "OTHER" is specified as the operating system type, the server
423	* is expected to return the "normal" user identification of the owner
424	* of this connection. "Normal" in this context may be taken to mean a
425	* string of characters which uniquely identifies the connection owner
426	* such as a user identifier assigned by the system administrator and
427	* used by such user as a mail identifier, or as the "user" part of a
428	* user/password pair used to gain access to system resources. When an
429	* operating system is specified (e.g., anything but "OTHER"), the user
430	* identifier is expected to be in a more or less immediately useful
431	* form - e.g., something that could be used as an argument to "finger"
432	* or as a mail address.
433	*/
434	if (!strncmp(token, "OTHER", 5))
435	return NULL;
436
437	/*
438	* Fourth token is the username
439	*/
440	token = vector[IDENT_INFO];
441
442	if (EmptyString(token))
443	return NULL;
444
445	while (IsSpace(*token))
446	++token;
447
448	while (token == '~' \|\| token == '^')
449	++token;
450
451	/*
452	* Look for the end of the username, terminators are '\0, @, <SPACE>, :'
453	*/
454	for (end = token; *end; ++end)
455	if (IsSpace(end) \|\| '@' == end \|\| ':' == *end)
456	break;
457	*end = '\0';
458
459	return token;
460	}
461
462	/*
463	* read_auth_reply - read the reply (if any) from the ident server
464	* we connected to.
465	* We only give it one shot, if the reply isn't good the first time
466	* fail the authentication entirely. --Bleep
467	*/
468	static void
469	read_auth_reply(fde_t fd, void data)
470	{
471	struct AuthRequest *const auth = data;
472	const char *username = NULL;
473	ssize_t len = 0;
474	char buf[RFC1413_BUFSIZ + 1];
475
476	if ((len = recv(fd->fd, buf, RFC1413_BUFSIZ, 0)) > 0)
477	{
478	buf[len] = '\0';
479	username = check_ident_reply(buf);
480	}
481
482	fd_close(fd);
483
484	ClearAuth(auth);
485
486	if (EmptyString(username))
487	{
488	sendheader(auth->client, REPORT_FAIL_ID);
489	++ServerStats.is_abad;
490	}
491	else
492	{
493	strlcpy(auth->client->username, username, sizeof(auth->client->username));
494	sendheader(auth->client, REPORT_FIN_ID);
495	++ServerStats.is_asuc;
496	AddFlag(auth->client, FLAGS_GOTID);
497	}
498
499	release_auth_client(auth);
500	}
501
502	/*
503	* delete_auth()
504	*/
505	void
506	delete_auth(struct AuthRequest *auth)
507	{
508	if (IsDNSPending(auth))
509	delete_resolver_queries(auth);
510
511	if (IsDoingAuth(auth))
512	fd_close(&auth->fd);
513
514	if (IsInAuth(auth))
515	{
516	dlinkDelete(&auth->node, &auth_list);
517	ClearInAuth(auth);
518	}
519	}
520
521	/* auth_init
522	*
523	* Initialise the auth code
524	*/
525	void
526	auth_init(void)
527	{
528	static struct event timeout_auth_queries =
529	{
530	.name = "timeout_auth_queries_event",
531	.handler = timeout_auth_queries_event,
532	.when = 1
533	};
534
535	event_add(&timeout_auth_queries, NULL);
536	}