trunk/src/auth.c

/*
 *  ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
 *
 *  Copyright (c) 1997-2014 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"


static const char *const HeaderMessages[] =
{
  ":*** Looking up your hostname",
  ":*** Found your hostname",
  ":*** Couldn't look up your hostname",
  ":*** Checking Ident",
  ":*** Got Ident response",
  ":*** No Ident response",
  ":*** Your forward and reverse DNS do not match, ignoring hostname",
  ":*** Your hostname is too long, ignoring hostname"
};

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
};

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

static dlink_list auth_pending_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 *request = &client->localClient->auth;

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

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

  return request;
}

/*
 * 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 *client = auth->client;

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

  if (IsInAuth(auth))
  {
    dlinkDelete(&auth->node, &auth_pending_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->localClient->allow_read = MAX_FLOOD;
  comm_setflush(&client->localClient->fd, 1000, flood_recalc, client);

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

  read_packet(&client->localClient->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 *auth = vptr;

  ClearDNSPending(auth);

  if (!EmptyString(name))
  {
    const struct sockaddr_in *v4, *v4dns;
    const struct sockaddr_in6 *v6, *v6dns;

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

      if (memcmp(&v6->sin6_addr, &v6dns->sin6_addr, sizeof(struct in6_addr)) != 0)
      {
        sendheader(auth->client, REPORT_IP_MISMATCH);
        release_auth_client(auth);
        return;
      }
    }
    else
    {
      v4 = (const struct sockaddr_in *)&auth->client->localClient->ip;
      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 int
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->localClient->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);
    ilog(LOG_TYPE_IRCD, "Unable to create auth socket for %s",
        get_client_name(auth->client, SHOW_IP));
    ++ServerStats.is_abad;
    return 0;
  }

  sendheader(auth->client, REPORT_DO_ID);

  /*
   * get the local address of the client and bind to that to
   * make the auth request.  This used to be done only for
   * ifdef VIRTUAL_HOST, but needs to be done for all clients
   * since the ident request must originate from that same address--
   * and machines with multiple IP addresses are common now
   */
  memset(&localaddr, 0, locallen);
  getsockname(auth->client->localClient->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->localClient->ip.ss.ss_family,
      GlobalSetOptions.ident_timeout);
  return 1; /* We suceed here for now */
}

/*
 * 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 *auth = NULL;

  assert(client_p);

  auth = make_auth_request(client_p);
  SetInAuth(auth);
  dlinkAddTail(auth, &auth->node, &auth_pending_list);

  sendheader(client_p, REPORT_DO_DNS);

  SetDNSPending(auth);

  if (ConfigGeneral.disable_auth == 0)
  {
    SetDoingAuth(auth);
    start_auth_query(auth);
  }

  gethost_byaddr(auth_dns_callback, auth, &client_p->localClient->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 *ptr = NULL, *ptr_next = NULL;

  DLINK_FOREACH_SAFE(ptr, ptr_next, auth_pending_list.head)
  {
    struct AuthRequest *auth = ptr->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);
    }

    ilog(LOG_TYPE_IRCD, "DNS/AUTH timeout %s",
         get_client_name(auth->client, SHOW_IP));
    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 *auth = data;
  struct irc_ssaddr us;
  struct irc_ssaddr them;
  char authbuf[32];
  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->localClient->fd.fd, (struct sockaddr *)&us, &ulen) ||
      getpeername(auth->client->localClient->fd.fd, (struct sockaddr *)&them, &tlen))
  {
    ilog(LOG_TYPE_IRCD, "auth get{sock,peer}name error for %s",
         get_client_name(auth->client, SHOW_IP));
    auth_error(auth);
    return;
  }

  v6 = (struct sockaddr_in6 *)&us;
  uport = ntohs(v6->sin6_port);
  v6 = (struct sockaddr_in6 *)&them;
  tport = ntohs(v6->sin6_port);
  remove_ipv6_mapping(&us);
  remove_ipv6_mapping(&them);

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

  if (send(fd->fd, authbuf, strlen(authbuf), 0) == -1)
  {
    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 *reply)
{
  char *token = NULL, *end = NULL;
  char *vector[USERID_TOKEN_COUNT];
  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 *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;
    SetGotId(auth->client);
  }

  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_pending_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:	4565
Committed:	Sun Aug 24 10:27:40 2014 UTC (9 years, 7 months ago) by michael
Content type:	text/x-csrc
File size:	14256 byte(s)
Log Message:	- Update GPL 2 license headers
#	Content
1	/*
2	* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3	*
4	* Copyright (c) 1997-2014 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	static const char *const HeaderMessages[] =
57	{
58	":*** Looking up your hostname",
59	":*** Found your hostname",
60	":*** Couldn't look up your hostname",
61	":*** Checking Ident",
62	":*** Got Ident response",
63	":*** No Ident response",
64	":*** Your forward and reverse DNS do not match, ignoring hostname",
65	":*** Your hostname is too long, ignoring hostname"
66	};
67
68	enum
69	{
70	REPORT_DO_DNS,
71	REPORT_FIN_DNS,
72	REPORT_FAIL_DNS,
73	REPORT_DO_ID,
74	REPORT_FIN_ID,
75	REPORT_FAIL_ID,
76	REPORT_IP_MISMATCH,
77	REPORT_HOST_TOOLONG
78	};
79
80	#define sendheader(c, i) sendto_one_notice((c), &me, HeaderMessages[(i)])
81
82	static dlink_list auth_pending_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 *request = &client->localClient->auth;
94
95	memset(request, 0, sizeof(*request));
96
97	request->client = client;
98	request->timeout = CurrentTime + CONNECTTIMEOUT;
99
100	return request;
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 *client = auth->client;
112
113	if (IsDoingAuth(auth) \|\| IsDNSPending(auth))
114	return;
115
116	if (IsInAuth(auth))
117	{
118	dlinkDelete(&auth->node, &auth_pending_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->localClient->allow_read = MAX_FLOOD;
128	comm_setflush(&client->localClient->fd, 1000, flood_recalc, client);
129
130	client->localClient->since = CurrentTime;
131	client->localClient->lasttime = CurrentTime;
132	client->localClient->firsttime = CurrentTime;
133	client->flags \|= FLAGS_FINISHED_AUTH;
134
135	read_packet(&client->localClient->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 *auth = vptr;
149
150	ClearDNSPending(auth);
151
152	if (!EmptyString(name))
153	{
154	const struct sockaddr_in v4, v4dns;
155	const struct sockaddr_in6 v6, v6dns;
156
157	if (auth->client->localClient->ip.ss.ss_family == AF_INET6)
158	{
159	v6 = (const struct sockaddr_in6 *)&auth->client->localClient->ip;
160	v6dns = (const struct sockaddr_in6 *)addr;
161
162	if (memcmp(&v6->sin6_addr, &v6dns->sin6_addr, sizeof(struct in6_addr)) != 0)
163	{
164	sendheader(auth->client, REPORT_IP_MISMATCH);
165	release_auth_client(auth);
166	return;
167	}
168	}
169	else
170	{
171	v4 = (const struct sockaddr_in *)&auth->client->localClient->ip;
172	v4dns = (const struct sockaddr_in *)addr;
173
174	if (v4->sin_addr.s_addr != v4dns->sin_addr.s_addr)
175	{
176	sendheader(auth->client, REPORT_IP_MISMATCH);
177	release_auth_client(auth);
178	return;
179	}
180	}
181
182	if (namelength > HOSTLEN)
183	sendheader(auth->client, REPORT_HOST_TOOLONG);
184	else
185	{
186	strlcpy(auth->client->host, name, sizeof(auth->client->host));
187	sendheader(auth->client, REPORT_FIN_DNS);
188	}
189	}
190	else
191	sendheader(auth->client, REPORT_FAIL_DNS);
192
193	release_auth_client(auth);
194	}
195
196	/*
197	* authsenderr - handle auth send errors
198	*/
199	static void
200	auth_error(struct AuthRequest *auth)
201	{
202	++ServerStats.is_abad;
203
204	fd_close(&auth->fd);
205
206	ClearAuth(auth);
207
208	sendheader(auth->client, REPORT_FAIL_ID);
209
210	release_auth_client(auth);
211	}
212
213	/*
214	* start_auth_query - Flag the client to show that an attempt to
215	* contact the ident server on
216	* the client's host. The connect and subsequently the socket are all put
217	* into 'non-blocking' mode. Should the connect or any later phase of the
218	* identifing process fail, it is aborted and the user is given a username
219	* of "unknown".
220	*/
221	static int
222	start_auth_query(struct AuthRequest *auth)
223	{
224	struct irc_ssaddr localaddr;
225	socklen_t locallen = sizeof(struct irc_ssaddr);
226	struct sockaddr_in6 *v6;
227
228	/* open a socket of the same type as the client socket */
229	if (comm_open(&auth->fd, auth->client->localClient->ip.ss.ss_family,
230	SOCK_STREAM, 0, "ident") == -1)
231	{
232	report_error(L_ALL, "creating auth stream socket %s:%s",
233	get_client_name(auth->client, SHOW_IP), errno);
234	ilog(LOG_TYPE_IRCD, "Unable to create auth socket for %s",
235	get_client_name(auth->client, SHOW_IP));
236	++ServerStats.is_abad;
237	return 0;
238	}
239
240	sendheader(auth->client, REPORT_DO_ID);
241
242	/*
243	* get the local address of the client and bind to that to
244	* make the auth request. This used to be done only for
245	* ifdef VIRTUAL_HOST, but needs to be done for all clients
246	* since the ident request must originate from that same address--
247	* and machines with multiple IP addresses are common now
248	*/
249	memset(&localaddr, 0, locallen);
250	getsockname(auth->client->localClient->fd.fd, (struct sockaddr*)&localaddr,
251	&locallen);
252
253	remove_ipv6_mapping(&localaddr);
254	v6 = (struct sockaddr_in6 *)&localaddr;
255	v6->sin6_port = htons(0);
256	localaddr.ss_port = htons(0);
257
258	comm_connect_tcp(&auth->fd, auth->client->sockhost, RFC1413_PORT,
259	(struct sockaddr *)&localaddr, localaddr.ss_len, auth_connect_callback,
260	auth, auth->client->localClient->ip.ss.ss_family,
261	GlobalSetOptions.ident_timeout);
262	return 1; /* We suceed here for now */
263	}
264
265	/*
266	* start_auth
267	*
268	* inputs - pointer to client to auth
269	* output - NONE
270	* side effects - starts auth (identd) and dns queries for a client
271	*/
272	void
273	start_auth(struct Client *client_p)
274	{
275	struct AuthRequest *auth = NULL;
276
277	assert(client_p);
278
279	auth = make_auth_request(client_p);
280	SetInAuth(auth);
281	dlinkAddTail(auth, &auth->node, &auth_pending_list);
282
283	sendheader(client_p, REPORT_DO_DNS);
284
285	SetDNSPending(auth);
286
287	if (ConfigGeneral.disable_auth == 0)
288	{
289	SetDoingAuth(auth);
290	start_auth_query(auth);
291	}
292
293	gethost_byaddr(auth_dns_callback, auth, &client_p->localClient->ip);
294	}
295
296	/*
297	* timeout_auth_queries - timeout resolver and identd requests
298	* allow clients through if requests failed
299	*/
300	static void
301	timeout_auth_queries_event(void *notused)
302	{
303	dlink_node ptr = NULL, ptr_next = NULL;
304
305	DLINK_FOREACH_SAFE(ptr, ptr_next, auth_pending_list.head)
306	{
307	struct AuthRequest *auth = ptr->data;
308
309	if (auth->timeout > CurrentTime)
310	break;
311
312	if (IsDoingAuth(auth))
313	{
314	++ServerStats.is_abad;
315	fd_close(&auth->fd);
316	ClearAuth(auth);
317	sendheader(auth->client, REPORT_FAIL_ID);
318	}
319
320	if (IsDNSPending(auth))
321	{
322	delete_resolver_queries(auth);
323	ClearDNSPending(auth);
324	sendheader(auth->client, REPORT_FAIL_DNS);
325	}
326
327	ilog(LOG_TYPE_IRCD, "DNS/AUTH timeout %s",
328	get_client_name(auth->client, SHOW_IP));
329	release_auth_client(auth);
330	}
331	}
332
333	/*
334	* auth_connect_callback() - deal with the result of comm_connect_tcp()
335	*
336	* If the connection failed, we simply close the auth fd and report
337	* a failure. If the connection suceeded send the ident server a query
338	* giving "theirport , ourport". The write is only attempted once so
339	* it is deemed to be a fail if the entire write doesn't write all the
340	* data given. This shouldnt be a problem since the socket should have
341	* a write buffer far greater than this message to store it in should
342	* problems arise. -avalon
343	*/
344	static void
345	auth_connect_callback(fde_t fd, int error, void data)
346	{
347	struct AuthRequest *auth = data;
348	struct irc_ssaddr us;
349	struct irc_ssaddr them;
350	char authbuf[32];
351	socklen_t ulen = sizeof(struct irc_ssaddr);
352	socklen_t tlen = sizeof(struct irc_ssaddr);
353	uint16_t uport, tport;
354	struct sockaddr_in6 *v6;
355
356	if (error != COMM_OK)
357	{
358	auth_error(auth);
359	return;
360	}
361
362	if (getsockname(auth->client->localClient->fd.fd, (struct sockaddr *)&us, &ulen) \|\|
363	getpeername(auth->client->localClient->fd.fd, (struct sockaddr *)&them, &tlen))
364	{
365	ilog(LOG_TYPE_IRCD, "auth get{sock,peer}name error for %s",
366	get_client_name(auth->client, SHOW_IP));
367	auth_error(auth);
368	return;
369	}
370
371	v6 = (struct sockaddr_in6 *)&us;
372	uport = ntohs(v6->sin6_port);
373	v6 = (struct sockaddr_in6 *)&them;
374	tport = ntohs(v6->sin6_port);
375	remove_ipv6_mapping(&us);
376	remove_ipv6_mapping(&them);
377
378	snprintf(authbuf, sizeof(authbuf), "%u, %u\r\n", tport, uport);
379
380	if (send(fd->fd, authbuf, strlen(authbuf), 0) == -1)
381	{
382	auth_error(auth);
383	return;
384	}
385
386	comm_setselect(fd, COMM_SELECT_READ, read_auth_reply, auth, 0);
387	}
388
389	/** Enum used to index ident reply fields in a human-readable way. */
390	enum IdentReplyFields
391	{
392	IDENT_PORT_NUMBERS,
393	IDENT_REPLY_TYPE,
394	IDENT_OS_TYPE,
395	IDENT_INFO,
396	USERID_TOKEN_COUNT
397	};
398
399	/** Parse an ident reply line and extract the userid from it.
400	* \param reply The ident reply line.
401	* \return The userid, or NULL on parse failure.
402	*/
403	static const char *
404	check_ident_reply(char *reply)
405	{
406	char token = NULL, end = NULL;
407	char *vector[USERID_TOKEN_COUNT];
408	int count = token_vector(reply, ':', vector, USERID_TOKEN_COUNT);
409
410	if (USERID_TOKEN_COUNT != count)
411	return NULL;
412
413	/*
414	* Second token is the reply type
415	*/
416	token = vector[IDENT_REPLY_TYPE];
417
418	if (EmptyString(token))
419	return NULL;
420
421	while (IsSpace(*token))
422	++token;
423
424	if (strncmp(token, "USERID", 6))
425	return NULL;
426
427	/*
428	* Third token is the os type
429	*/
430	token = vector[IDENT_OS_TYPE];
431
432	if (EmptyString(token))
433	return NULL;
434
435	while (IsSpace(*token))
436	++token;
437
438	/*
439	* Unless "OTHER" is specified as the operating system type, the server
440	* is expected to return the "normal" user identification of the owner
441	* of this connection. "Normal" in this context may be taken to mean a
442	* string of characters which uniquely identifies the connection owner
443	* such as a user identifier assigned by the system administrator and
444	* used by such user as a mail identifier, or as the "user" part of a
445	* user/password pair used to gain access to system resources. When an
446	* operating system is specified (e.g., anything but "OTHER"), the user
447	* identifier is expected to be in a more or less immediately useful
448	* form - e.g., something that could be used as an argument to "finger"
449	* or as a mail address.
450	*/
451	if (!strncmp(token, "OTHER", 5))
452	return NULL;
453
454	/*
455	* Fourth token is the username
456	*/
457	token = vector[IDENT_INFO];
458
459	if (EmptyString(token))
460	return NULL;
461
462	while (IsSpace(*token))
463	++token;
464
465	while (token == '~' \|\| token == '^')
466	++token;
467
468	/*
469	* Look for the end of the username, terminators are '\0, @, <SPACE>, :'
470	*/
471	for (end = token; *end; ++end)
472	if (IsSpace(end) \|\| '@' == end \|\| ':' == *end)
473	break;
474	*end = '\0';
475
476	return token;
477	}
478
479	/*
480	* read_auth_reply - read the reply (if any) from the ident server
481	* we connected to.
482	* We only give it one shot, if the reply isn't good the first time
483	* fail the authentication entirely. --Bleep
484	*/
485	static void
486	read_auth_reply(fde_t fd, void data)
487	{
488	struct AuthRequest *auth = data;
489	const char *username = NULL;
490	ssize_t len = 0;
491	char buf[RFC1413_BUFSIZ + 1];
492
493	if ((len = recv(fd->fd, buf, RFC1413_BUFSIZ, 0)) > 0)
494	{
495	buf[len] = '\0';
496	username = check_ident_reply(buf);
497	}
498
499	fd_close(fd);
500
501	ClearAuth(auth);
502
503	if (EmptyString(username))
504	{
505	sendheader(auth->client, REPORT_FAIL_ID);
506	++ServerStats.is_abad;
507	}
508	else
509	{
510	strlcpy(auth->client->username, username, sizeof(auth->client->username));
511	sendheader(auth->client, REPORT_FIN_ID);
512	++ServerStats.is_asuc;
513	SetGotId(auth->client);
514	}
515
516	release_auth_client(auth);
517	}
518
519	/*
520	* delete_auth()
521	*/
522	void
523	delete_auth(struct AuthRequest *auth)
524	{
525	if (IsDNSPending(auth))
526	delete_resolver_queries(auth);
527
528	if (IsDoingAuth(auth))
529	fd_close(&auth->fd);
530
531	if (IsInAuth(auth))
532	{
533	dlinkDelete(&auth->node, &auth_pending_list);
534	ClearInAuth(auth);
535	}
536	}
537
538	/* auth_init
539	*
540	* Initialise the auth code
541	*/
542	void
543	auth_init(void)
544	{
545	static struct event timeout_auth_queries =
546	{
547	.name = "timeout_auth_queries_event",
548	.handler = timeout_auth_queries_event,
549	.when = 1
550	};
551
552	event_add(&timeout_auth_queries, NULL);
553	}