trunk/src/auth.c

/*
 *  ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
 *
 *  Copyright (c) 1997-2019 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"


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)])

static dlink_list auth_list;


/*! \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;
  auth->timeout = CurrentTime + CONNECTTIMEOUT;

  return auth;
}

/*! \brief Unlink auth request from auth_list and free memory
 * \param auth The allocated auth request to cleanup.
 */
static void
auth_free(struct AuthRequest *auth)
{
  assert(dlinkFind(&auth_list, auth));

  dlinkDelete(&auth->node, &auth_list);

  assert(dlinkFind(&auth_list, auth) == NULL);

  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, 1000, flood_recalc, client);

  client->connection->since     = CurrentTime;
  client->connection->lasttime  = CurrentTime;
  client->connection->firsttime = CurrentTime;
  AddFlag(client, FLAGS_FINISHED_AUTH);

  strlcpy(client->realhost, client->host, sizeof(client->realhost));

  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 (EmptyString(name))
    auth_sendheader(auth->client, REPORT_FAIL_DNS);
  else if (address_compare(addr, &auth->client->ip, false) == 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 ((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, 0);
}

/*! \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,
                   GlobalSetOptions.ident_timeout);
}

/*
 * 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_p)
{
  struct AuthRequest *auth = auth_make(client_p);

  assert(client_p);
  assert(client_p->connection);

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

  auth_sendheader(client_p, REPORT_DO_DNS);

  auth->dns_pending = true;

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

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

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

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

  if (auth->dns_pending == true)
  {
    delete_resolver_queries(auth);
    auth->dns_pending = false;
  }

  auth_free(auth);
}

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

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

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

    if (auth->timeout > CurrentTime)
      break;

    if (auth->ident_pending == true)
    {
      ++ServerStats.is_abad;

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

      auth_sendheader(auth->client, REPORT_FAIL_ID);
    }

    if (auth->dns_pending == true)
    {
      delete_resolver_queries(auth);
      auth->dns_pending = false;

      auth_sendheader(auth->client, REPORT_FAIL_DNS);
    }

    auth_release_client(auth);
  }
}

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

  event_add(&timeout_auth_queries, NULL);
}
Revision:	8885
Committed:	Fri Apr 19 11:48:00 2019 UTC (7 years, 5 months ago) by michael
Content type:	text/x-csrc
File size:	15028 byte(s)
Log Message:	- auth.c:auth_free(): set auth->client pointer to NULL
#	User	Rev	Content
1	adx	30	/*
2	michael	2916	* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3	adx	30	*
4	michael	8752	* Copyright (c) 1997-2019 ircd-hybrid development team
5	adx	30	*
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	michael	4565	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
19	adx	30	* USA
20			*/
21
22	michael	3324	/*! \file auth.c
23	michael	8306	* \brief Implementation of DNS and ident lookups.
24	michael	2916	* \version $Id$
25			*/
26
27	adx	30	/*
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	michael	1309
38	adx	30	#include "stdinc.h"
39			#include "list.h"
40	michael	1011	#include "ircd_defs.h"
41			#include "fdlist.h"
42	michael	3324	#include "auth.h"
43	michael	1309	#include "conf.h"
44	adx	30	#include "client.h"
45			#include "event.h"
46			#include "irc_string.h"
47			#include "ircd.h"
48			#include "packet.h"
49	michael	3322	#include "res.h"
50	adx	30	#include "s_bsd.h"
51	michael	1309	#include "log.h"
52	adx	30	#include "send.h"
53	michael	8385	#include "memory.h"
54	michael	8881	#include "misc.h"
55	adx	30
56	michael	1011
57	michael	2916	enum
58			{
59	adx	30	REPORT_DO_DNS,
60			REPORT_FIN_DNS,
61			REPORT_FAIL_DNS,
62			REPORT_DO_ID,
63			REPORT_FIN_ID,
64			REPORT_FAIL_ID,
65			REPORT_IP_MISMATCH,
66	michael	8217	REPORT_HOST_TOOLONG,
67			REPORT_HOST_INVALID
68	adx	30	};
69
70	michael	5888	static const char *const HeaderMessages[] =
71			{
72			[REPORT_DO_DNS] = ":*** Looking up your hostname",
73			[REPORT_FIN_DNS] = ":*** Found your hostname",
74			[REPORT_FAIL_DNS] = ":*** Couldn't look up your hostname",
75			[REPORT_DO_ID] = ":*** Checking Ident",
76			[REPORT_FIN_ID] = ":*** Got Ident response",
77			[REPORT_FAIL_ID] = ":*** No Ident response",
78			[REPORT_IP_MISMATCH] = ":*** Your forward and reverse DNS do not match, ignoring hostname",
79	michael	8217	[REPORT_HOST_TOOLONG] = ":*** Your hostname is too long, ignoring hostname",
80			[REPORT_HOST_INVALID] = ":*** Your hostname contains illegal characters, ignoring hostname"
81	michael	5888	};
82
83	michael	8306	#define auth_sendheader(c, i) sendto_one_notice((c), &me, "%s", HeaderMessages[(i)])
84	adx	30
85	michael	6478	static dlink_list auth_list;
86	adx	30
87	michael	4094
88	michael	8349	/*! \brief Allocate a new auth request.
89			* \param client The client being looked up.
90			* \return The newly allocated auth request.
91	adx	30	*/
92			static struct AuthRequest *
93	michael	8339	auth_make(struct Client *client)
94	adx	30	{
95	michael	8385	struct AuthRequest auth = xcalloc(sizeof(auth));
96	adx	30
97	michael	6690	auth->client = client;
98	michael	8470	auth->client->connection->auth = auth;
99	michael	6690	auth->timeout = CurrentTime + CONNECTTIMEOUT;
100	michael	2181
101	michael	6690	return auth;
102	adx	30	}
103
104	michael	8470	/*! \brief Unlink auth request from auth_list and free memory
105			* \param auth The allocated auth request to cleanup.
106			*/
107			static void
108			auth_free(struct AuthRequest *auth)
109			{
110			assert(dlinkFind(&auth_list, auth));
111	michael	8885
112	michael	8470	dlinkDelete(&auth->node, &auth_list);
113	michael	8885
114	michael	8470	assert(dlinkFind(&auth_list, auth) == NULL);
115
116	michael	8885	auth->client = NULL;
117	michael	8470	xfree(auth);
118			}
119
120	michael	8306	/*! \brief Release auth client from auth system. This adds the client into the
121			* local client lists so it can be read by the main io processing loop.
122			* \param auth Pointer to AuthRequest struct to release
123	adx	30	*/
124	michael	8304	static void
125	michael	8306	auth_release_client(struct AuthRequest *auth)
126	adx	30	{
127	michael	8470	struct Client *client = auth->client;
128	michael	992
129	michael	8813	assert(client);
130			assert(client->connection);
131
132	michael	8721	if (auth->ident_pending == true \|\| auth->dns_pending == true)
133	michael	992	return;
134
135	michael	8470	auth_free(auth);
136	michael	8339	client->connection->auth = NULL;
137
138	adx	30	/*
139			* When a client has auth'ed, we want to start reading what it sends
140			* us. This is what read_packet() does.
141			* -- adrian
142			*/
143	michael	8339	comm_setflush(client->connection->fd, 1000, flood_recalc, client);
144	michael	650
145	michael	4588	client->connection->since = CurrentTime;
146			client->connection->lasttime = CurrentTime;
147			client->connection->firsttime = CurrentTime;
148	michael	8298	AddFlag(client, FLAGS_FINISHED_AUTH);
149	michael	650
150	michael	8214	strlcpy(client->realhost, client->host, sizeof(client->realhost));
151
152	michael	8339	read_packet(client->connection->fd, client);
153	adx	30	}
154	michael	2916
155	michael	8218	/*! Checks if a hostname is valid and doesn't contain illegal characters
156			* \param hostname The string to verify
157			* \return 1 if it is valid, 0 if it isn't
158			*/
159	michael	8656	static bool
160	michael	8217	auth_verify_hostname(const char *hostname)
161			{
162			const char *p = hostname;
163
164			assert(p);
165
166			if (EmptyString(p) \|\| p == '.' \|\| p == ':')
167	michael	8656	return false;
168	michael	8217
169			for (; *p; ++p)
170			if (!IsHostChar(*p))
171	michael	8656	return false;
172	michael	8217
173	michael	8656	return true;
174	michael	8217	}
175
176	michael	8306	/*! \brief Handle a complete DNS lookup. Send the client on its way to a connection
177			* completion, regardless of success or failure.
178			* \param vptr The pending struct AuthRequest.
179			* \param addr IP address being resolved.
180			* \param name Resolved name, or NULL if lookup failed.
181			* \param namelength String length of the resolved hostname pointed by 'name'
182	adx	30	*/
183			static void
184	michael	4408	auth_dns_callback(void vptr, const struct irc_ssaddr addr, const char *name, size_t namelength)
185	adx	30	{
186	michael	4854	struct AuthRequest *const auth = vptr;
187	adx	30
188	michael	8813	assert(auth->client);
189			assert(auth->client->connection);
190
191	michael	8721	auth->dns_pending = false;
192	adx	30
193	michael	8431	if (EmptyString(name))
194			auth_sendheader(auth->client, REPORT_FAIL_DNS);
195	michael	8883	else if (address_compare(addr, &auth->client->ip, false) == false)
196			auth_sendheader(auth->client, REPORT_IP_MISMATCH);
197			else if (namelength > HOSTLEN)
198			auth_sendheader(auth->client, REPORT_HOST_TOOLONG);
199			else if (auth_verify_hostname(name) == false)
200			auth_sendheader(auth->client, REPORT_HOST_INVALID);
201	michael	8431	else
202	adx	30	{
203	michael	8883	strlcpy(auth->client->host, name, sizeof(auth->client->host));
204			auth_sendheader(auth->client, REPORT_FIN_DNS);
205	adx	30	}
206
207	michael	8306	auth_release_client(auth);
208	adx	30	}
209
210			/*
211	michael	8306	* auth_error - handle auth send errors
212	adx	30	*/
213			static void
214			auth_error(struct AuthRequest *auth)
215			{
216	michael	8524	assert(auth);
217			assert(auth->fd);
218	michael	8813	assert(auth->client);
219			assert(auth->client->connection);
220	michael	8524
221	michael	896	++ServerStats.is_abad;
222	adx	30
223	michael	8339	fd_close(auth->fd);
224			auth->fd = NULL;
225	michael	8721	auth->ident_pending = false;
226	michael	8339
227	michael	8306	auth_sendheader(auth->client, REPORT_FAIL_ID);
228	adx	30
229	michael	8306	auth_release_client(auth);
230	adx	30	}
231
232	michael	4309	/** Enum used to index ident reply fields in a human-readable way. */
233			enum IdentReplyFields
234			{
235			IDENT_PORT_NUMBERS,
236			IDENT_REPLY_TYPE,
237			IDENT_OS_TYPE,
238			IDENT_INFO,
239			USERID_TOKEN_COUNT
240			};
241
242			/** Parse an ident reply line and extract the userid from it.
243			* \param reply The ident reply line.
244			* \return The userid, or NULL on parse failure.
245			*/
246			static const char *
247	michael	8306	auth_check_ident_reply(char *const reply)
248	michael	4309	{
249			char token = NULL, end = NULL;
250			char *vector[USERID_TOKEN_COUNT];
251	michael	7584	const unsigned int count = token_vector(reply, ':', vector, USERID_TOKEN_COUNT);
252	michael	4309
253			if (USERID_TOKEN_COUNT != count)
254			return NULL;
255
256			/*
257			* Second token is the reply type
258			*/
259			token = vector[IDENT_REPLY_TYPE];
260
261			if (EmptyString(token))
262			return NULL;
263
264			while (IsSpace(*token))
265			++token;
266
267			if (strncmp(token, "USERID", 6))
268			return NULL;
269
270			/*
271			* Third token is the os type
272			*/
273			token = vector[IDENT_OS_TYPE];
274
275			if (EmptyString(token))
276			return NULL;
277
278			while (IsSpace(*token))
279			++token;
280
281			/*
282			* Unless "OTHER" is specified as the operating system type, the server
283			* is expected to return the "normal" user identification of the owner
284			* of this connection. "Normal" in this context may be taken to mean a
285			* string of characters which uniquely identifies the connection owner
286			* such as a user identifier assigned by the system administrator and
287			* used by such user as a mail identifier, or as the "user" part of a
288			* user/password pair used to gain access to system resources. When an
289			* operating system is specified (e.g., anything but "OTHER"), the user
290			* identifier is expected to be in a more or less immediately useful
291			* form - e.g., something that could be used as an argument to "finger"
292			* or as a mail address.
293			*/
294	michael	8620	if (strncmp(token, "OTHER", 5) == 0)
295	michael	4309	return NULL;
296
297			/*
298			* Fourth token is the username
299			*/
300			token = vector[IDENT_INFO];
301
302			if (EmptyString(token))
303			return NULL;
304
305			while (IsSpace(*token))
306			++token;
307
308			while (token == '~' \|\| token == '^')
309			++token;
310
311			/*
312			* Look for the end of the username, terminators are '\0, @, <SPACE>, :'
313			*/
314			for (end = token; *end; ++end)
315			if (IsSpace(end) \|\| '@' == end \|\| ':' == *end)
316			break;
317			*end = '\0';
318
319			return token;
320			}
321
322	michael	8306	/*! \brief Read the reply (if any) from the ident server we connected to. We
323			* only give it one shot, if the reply isn't good the first time fail
324			* the authentication entirely. --Bleep
325	michael	8349	* \param F The socket/fd to read from.
326	michael	8306	* \param data The request to read.
327	adx	30	*/
328			static void
329	michael	8349	auth_read_reply(fde_t F, void data)
330	adx	30	{
331	michael	4854	struct AuthRequest *const auth = data;
332	michael	4309	const char *username = NULL;
333			ssize_t len = 0;
334			char buf[RFC1413_BUFSIZ + 1];
335	adx	30
336	michael	8349	assert(auth->fd == F);
337	michael	8813	assert(auth->client);
338			assert(auth->client->connection);
339	michael	8339
340	michael	8819	if ((len = recv(auth->fd->fd, buf, sizeof(buf) - 1, 0)) > 0)
341	adx	30	{
342			buf[len] = '\0';
343	michael	8306	username = auth_check_ident_reply(buf);
344	adx	30	}
345
346	michael	8339	fd_close(auth->fd);
347			auth->fd = NULL;
348	michael	8721	auth->ident_pending = false;
349	michael	8339
350	michael	4309	if (EmptyString(username))
351	adx	30	{
352	michael	8306	auth_sendheader(auth->client, REPORT_FAIL_ID);
353	michael	896	++ServerStats.is_abad;
354	adx	30	}
355			else
356			{
357	michael	4309	strlcpy(auth->client->username, username, sizeof(auth->client->username));
358	michael	8306	auth_sendheader(auth->client, REPORT_FIN_ID);
359	michael	896	++ServerStats.is_asuc;
360	michael	6313	AddFlag(auth->client, FLAGS_GOTID);
361	adx	30	}
362
363	michael	8306	auth_release_client(auth);
364	adx	30	}
365
366			/*
367	michael	8306	* auth_connect_callback() - deal with the result of comm_connect_tcp()
368			*
369			* If the connection failed, we simply close the auth fd and report
370			* a failure. If the connection suceeded send the ident server a query
371			* giving "theirport , ourport". The write is only attempted once so
372			* it is deemed to be a fail if the entire write doesn't write all the
373			* data given. This shouldnt be a problem since the socket should have
374			* a write buffer far greater than this message to store it in should
375			* problems arise. -avalon
376			*/
377			static void
378	michael	8349	auth_connect_callback(fde_t F, int error, void data)
379	michael	8306	{
380			struct AuthRequest *const auth = data;
381			struct irc_ssaddr us;
382			struct irc_ssaddr them;
383			char authbuf[16];
384			ssize_t len = 0;
385			socklen_t ulen = sizeof(struct irc_ssaddr);
386			socklen_t tlen = sizeof(struct irc_ssaddr);
387			uint16_t uport, tport;
388			struct sockaddr_in6 *v6;
389
390	michael	8813	assert(auth->fd == F);
391			assert(auth->client);
392			assert(auth->client->connection);
393
394	michael	8306	if (error != COMM_OK)
395			{
396			auth_error(auth);
397			return;
398			}
399
400	michael	8339	if (getsockname(auth->client->connection->fd->fd, (struct sockaddr *)&us, &ulen) \|\|
401			getpeername(auth->client->connection->fd->fd, (struct sockaddr *)&them, &tlen))
402	michael	8306	{
403			report_error(L_ALL, "auth get{sock,peer}name error %s:%s",
404			client_get_name(auth->client, SHOW_IP), errno);
405			auth_error(auth);
406			return;
407			}
408
409			v6 = (struct sockaddr_in6 *)&us;
410			uport = ntohs(v6->sin6_port);
411			v6 = (struct sockaddr_in6 *)&them;
412			tport = ntohs(v6->sin6_port);
413
414			len = snprintf(authbuf, sizeof(authbuf), "%u, %u\r\n", tport, uport);
415
416	michael	8349	if (send(F->fd, authbuf, len, 0) != len)
417	michael	8306	{
418			auth_error(auth);
419			return;
420			}
421
422	michael	8349	comm_setselect(F, COMM_SELECT_READ, auth_read_reply, auth, 0);
423	michael	8306	}
424
425			/*! \brief Flag the client to show an attempt to contact the ident server on
426			* the client's host. Should the connect or any later phase of the
427			* identifying process fail, it is aborted and the user is given a
428			* username of "unknown".
429			* \param auth The request for which to start the ident lookup.
430			*/
431			static void
432			auth_start_query(struct AuthRequest *auth)
433			{
434			struct irc_ssaddr localaddr;
435			socklen_t locallen = sizeof(struct irc_ssaddr);
436			struct sockaddr_in6 *v6;
437
438	michael	8813	assert(auth->client);
439			assert(auth->client->connection);
440
441	michael	8306	/* Open a socket of the same type as the client socket */
442	michael	8496	int fd = comm_socket(auth->client->ip.ss.ss_family, SOCK_STREAM, 0);
443	michael	8339	if (fd == -1)
444	michael	8306	{
445			report_error(L_ALL, "creating auth stream socket %s:%s",
446			client_get_name(auth->client, SHOW_IP), errno);
447			++ServerStats.is_abad;
448			return;
449			}
450
451	michael	8658	auth->fd = fd_open(fd, true, "ident");
452	michael	8721	auth->ident_pending = true;
453	michael	8339
454	michael	8306	auth_sendheader(auth->client, REPORT_DO_ID);
455
456			/*
457			* Get the local address of the client and bind to that to
458			* make the auth request.
459			*/
460			memset(&localaddr, 0, locallen);
461	michael	8339	getsockname(auth->client->connection->fd->fd, (struct sockaddr *)&localaddr, &locallen);
462	michael	8306
463			remove_ipv6_mapping(&localaddr);
464			v6 = (struct sockaddr_in6 *)&localaddr;
465			v6->sin6_port = htons(0);
466
467	michael	8872	comm_connect_tcp(auth->fd, &auth->client->ip, RFC1413_PORT,
468			&localaddr, auth_connect_callback, auth,
469			GlobalSetOptions.ident_timeout);
470	michael	8306	}
471
472			/*
473			* auth_start
474			*
475			* inputs - pointer to client to auth
476			* output - NONE
477			* side effects - starts auth (identd) and dns queries for a client
478			*/
479			void
480			auth_start(struct Client *client_p)
481			{
482	michael	8339	struct AuthRequest *auth = auth_make(client_p);
483	michael	8306
484	michael	8813	assert(client_p);
485			assert(client_p->connection);
486
487	michael	8306	dlinkAddTail(auth, &auth->node, &auth_list);
488
489			auth_sendheader(client_p, REPORT_DO_DNS);
490
491	michael	8721	auth->dns_pending = true;
492	michael	8306
493			if (ConfigGeneral.disable_auth == 0)
494			auth_start_query(auth);
495
496	michael	8496	gethost_byaddr(auth_dns_callback, auth, &client_p->ip);
497	michael	8306	}
498
499			/*
500	michael	7955	* auth_delete()
501	adx	30	*/
502	michael	2916	void
503	michael	7955	auth_delete(struct AuthRequest *auth)
504	adx	30	{
505	michael	8813	assert(auth->client);
506			assert(auth->client->connection);
507
508	michael	8721	if (auth->ident_pending == true)
509	michael	8306	{
510	michael	8339	fd_close(auth->fd);
511			auth->fd = NULL;
512	michael	8721	auth->ident_pending = false;
513	michael	8306	}
514
515	michael	8721	if (auth->dns_pending == true)
516	michael	8300	{
517	michael	992	delete_resolver_queries(auth);
518	michael	8721	auth->dns_pending = false;
519	michael	8300	}
520	adx	30
521	michael	8470	auth_free(auth);
522	adx	30	}
523	michael	4309
524	michael	8306	/*
525			* auth_timeout_queries - timeout resolver and identd requests
526			* allow clients through if requests failed
527			*/
528			static void
529			auth_timeout_queries(void *notused)
530			{
531			dlink_node node, node_next;
532
533			DLINK_FOREACH_SAFE(node, node_next, auth_list.head)
534			{
535			struct AuthRequest *auth = node->data;
536
537	michael	8813	assert(auth->client);
538			assert(auth->client->connection);
539
540	michael	8306	if (auth->timeout > CurrentTime)
541			break;
542
543	michael	8721	if (auth->ident_pending == true)
544	michael	8306	{
545			++ServerStats.is_abad;
546	michael	8349
547	michael	8339	fd_close(auth->fd);
548			auth->fd = NULL;
549	michael	8721	auth->ident_pending = false;
550	michael	8339
551	michael	8306	auth_sendheader(auth->client, REPORT_FAIL_ID);
552			}
553
554	michael	8721	if (auth->dns_pending == true)
555	michael	8306	{
556			delete_resolver_queries(auth);
557	michael	8721	auth->dns_pending = false;
558	michael	8306
559			auth_sendheader(auth->client, REPORT_FAIL_DNS);
560			}
561
562			auth_release_client(auth);
563			}
564			}
565
566	michael	4309	/* auth_init
567			*
568			* Initialise the auth code
569			*/
570			void
571			auth_init(void)
572			{
573			static struct event timeout_auth_queries =
574			{
575	michael	8306	.name = "auth_timeout_queries",
576			.handler = auth_timeout_queries,
577	michael	4309	.when = 1
578			};
579
580			event_add(&timeout_auth_queries, NULL);
581			}