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., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *  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_doing_list = { NULL, NULL, 0 };

static void timeout_auth_queries_event(void *);

static PF read_auth_reply;
static CNCB auth_connect_callback;

/* 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);
}

/*
 * 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_doing_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);

  dlinkAdd(client, &client->node, &global_client_list);

  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)
{
  struct AuthRequest *auth = vptr;

  ClearDNSPending(auth);

  if (name)
  {
    const struct sockaddr_in *v4, *v4dns;
#ifdef IPV6
    const struct sockaddr_in6 *v6, *v6dns;
#endif
    int good = 1;

#ifdef IPV6
    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);
        good = 0;
      }
    }
    else
#endif
    {
      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);
        good = 0;
      }
    }

    if (good && strlen(name) <= HOSTLEN)
    {
      strlcpy(auth->client->host, name,
              sizeof(auth->client->host));
      sendheader(auth->client, REPORT_FIN_DNS);
    }
    else if (strlen(name) > HOSTLEN)
      sendheader(auth->client, REPORT_HOST_TOOLONG);
  }
  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);
#ifdef IPV6
  struct sockaddr_in6 *v6;
#else
  struct sockaddr_in *v4;
#endif

  /* 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);

#ifdef IPV6
  remove_ipv6_mapping(&localaddr);
  v6 = (struct sockaddr_in6 *)&localaddr;
  v6->sin6_port = htons(0);
#else
  localaddr.ss_len = locallen;
  v4 = (struct sockaddr_in *)&localaddr;
  v4->sin_port = htons(0);
#endif
  localaddr.ss_port = htons(0);

  comm_connect_tcp(&auth->fd, auth->client->sockhost, 113,
      (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 */
}

/*
 * GetValidIdent - parse ident query reply from identd server
 *
 * Inputs        - pointer to ident buf
 * Output        - NULL if no valid ident found, otherwise pointer to name
 * Side effects  -
 */
/*
 * A few questions have been asked about this mess, obviously
 * it should have been commented better the first time.
 * The original idea was to remove all references to libc from ircd-hybrid.
 * Instead of having to write a replacement for sscanf(), I did a
 * rather gruseome parser here so we could remove this function call.
 * Note, that I had also removed a few floating point printfs as well (though
 * now we are still stuck with a few...)
 * Remember, we have a replacement ircd sprintf, we have bleeps fputs lib
 * it would have been nice to remove some unneeded code.
 * Oh well. If we don't remove libc stuff totally, then it would be
 * far cleaner to use sscanf()
 *
 * - Dianora
 */
static char *
GetValidIdent(char *buf)
{
  int   remp = 0;
  int   locp = 0;
  char* colon1Ptr;
  char* colon2Ptr;
  char* colon3Ptr;
  char* commaPtr;
  char* remotePortString;

  /* All this to get rid of a sscanf() fun. */
  remotePortString = buf;

  if ((colon1Ptr = strchr(remotePortString,':')) == NULL)
    return 0;
  *colon1Ptr = '\0';
  colon1Ptr++;

  if ((colon2Ptr = strchr(colon1Ptr,':')) == NULL)
    return 0;
  *colon2Ptr = '\0';
  colon2Ptr++;

  if ((commaPtr = strchr(remotePortString, ',')) == NULL)
    return 0;
  *commaPtr = '\0';
  commaPtr++;

  if ((remp = atoi(remotePortString)) == 0)
    return 0;

  if ((locp = atoi(commaPtr)) == 0)
    return 0;

  /* look for USERID bordered by first pair of colons */
  if (strstr(colon1Ptr, "USERID") == NULL)
    return 0;

  if ((colon3Ptr = strchr(colon2Ptr,':')) == NULL)
    return 0;
  *colon3Ptr = '\0';
  colon3Ptr++;
  return (colon3Ptr);
}

/*
 * 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_doing_list);

  sendheader(client_p, REPORT_DO_DNS);

  SetDNSPending(auth);

  if (ConfigFileEntry.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_doing_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;
#ifdef IPV6
  struct sockaddr_in6 *v6;
#else
  struct sockaddr_in *v4;
#endif

  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;
  }

#ifdef IPV6
  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);
#else
  v4 = (struct sockaddr_in *)&us;
  uport = ntohs(v4->sin_port);
  v4 = (struct sockaddr_in *)&them;
  tport = ntohs(v4->sin_port);
  us.ss_len = ulen;
  them.ss_len = tlen;
#endif

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

  if (send(fd->fd, authbuf, strlen(authbuf), 0) == -1)
  {
    auth_error(auth);
    return;
  }

  read_auth_reply(&auth->fd, auth);
}

/*
 * 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
 */
#define AUTH_BUFSIZ 128

static void
read_auth_reply(fde_t *fd, void *data)
{
  struct AuthRequest *auth = data;
  char *s = NULL;
  char *t = NULL;
  int len;
  int count;
  char buf[AUTH_BUFSIZ + 1]; /* buffer to read auth reply into */

  /* Why?
   * Well, recv() on many POSIX systems is a per-packet operation,
   * and we do not necessarily want this, because on lowspec machines,
   * the ident response may come back fragmented, thus resulting in an
   * invalid ident response, even if the ident response was really OK.
   *
   * So PLEASE do not change this code to recv without being aware of the
   * consequences.
   *
   *    --nenolod
   */
  len = read(fd->fd, buf, AUTH_BUFSIZ);

  if (len < 0)
  {
    if (ignoreErrno(errno))
      comm_setselect(fd, COMM_SELECT_READ, read_auth_reply, auth, 0);
    else
      auth_error(auth);
    return;
  }

  if (len > 0)
  {
    buf[len] = '\0';

    if ((s = GetValidIdent(buf)))
    {
      t = auth->client->username;

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

      for (count = USERLEN; *s && count; s++)
      {
        if (*s == '@')
          break;
        if (!IsSpace(*s) && *s != ':')
        {
          *t++ = *s;
          count--;
        }
      }

      *t = '\0';
    }
  }

  fd_close(fd);

  ClearAuth(auth);

  if (s == NULL)
  {
    sendheader(auth->client, REPORT_FAIL_ID);
    ++ServerStats.is_abad;
  }
  else
  {
    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_doing_list);
    ClearInAuth(auth);
  }
}
Revision:	4108
Committed:	Mon Jun 30 21:02:06 2014 UTC (12 years, 3 months ago) by michael
Content type:	text/x-csrc
File size:	15208 byte(s)
Log Message:	- Allow [ in usernames
#	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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
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_doing_list = { NULL, NULL, 0 };
83
84	static void timeout_auth_queries_event(void *);
85
86	static PF read_auth_reply;
87	static CNCB auth_connect_callback;
88
89	/* auth_init
90	*
91	* Initialise the auth code
92	*/
93	void
94	auth_init(void)
95	{
96	static struct event timeout_auth_queries =
97	{
98	.name = "timeout_auth_queries_event",
99	.handler = timeout_auth_queries_event,
100	.when = 1
101	};
102
103	event_add(&timeout_auth_queries, NULL);
104	}
105
106	/*
107	* make_auth_request - allocate a new auth request
108	*/
109	static struct AuthRequest *
110	make_auth_request(struct Client *client)
111	{
112	struct AuthRequest *request = &client->localClient->auth;
113
114	memset(request, 0, sizeof(*request));
115
116	request->client = client;
117	request->timeout = CurrentTime + CONNECTTIMEOUT;
118
119	return request;
120	}
121
122	/*
123	* release_auth_client - release auth client from auth system
124	* this adds the client into the local client lists so it can be read by
125	* the main io processing loop
126	*/
127	void
128	release_auth_client(struct AuthRequest *auth)
129	{
130	struct Client *client = auth->client;
131
132	if (IsDoingAuth(auth) \|\| IsDNSPending(auth))
133	return;
134
135	if (IsInAuth(auth))
136	{
137	dlinkDelete(&auth->node, &auth_doing_list);
138	ClearInAuth(auth);
139	}
140
141	/*
142	* When a client has auth'ed, we want to start reading what it sends
143	* us. This is what read_packet() does.
144	* -- adrian
145	*/
146	client->localClient->allow_read = MAX_FLOOD;
147	comm_setflush(&client->localClient->fd, 1000, flood_recalc, client);
148
149	dlinkAdd(client, &client->node, &global_client_list);
150
151	client->localClient->since = CurrentTime;
152	client->localClient->lasttime = CurrentTime;
153	client->localClient->firsttime = CurrentTime;
154	client->flags \|= FLAGS_FINISHED_AUTH;
155
156	read_packet(&client->localClient->fd, client);
157	}
158
159	/*
160	* auth_dns_callback - called when resolver query finishes
161	* if the query resulted in a successful search, name will contain
162	* a non-NULL pointer, otherwise name will be NULL.
163	* set the client on it's way to a connection completion, regardless
164	* of success of failure
165	*/
166	static void
167	auth_dns_callback(void vptr, const struct irc_ssaddr addr, const char *name)
168	{
169	struct AuthRequest *auth = vptr;
170
171	ClearDNSPending(auth);
172
173	if (name)
174	{
175	const struct sockaddr_in v4, v4dns;
176	#ifdef IPV6
177	const struct sockaddr_in6 v6, v6dns;
178	#endif
179	int good = 1;
180
181	#ifdef IPV6
182	if (auth->client->localClient->ip.ss.ss_family == AF_INET6)
183	{
184	v6 = (const struct sockaddr_in6 *)&auth->client->localClient->ip;
185	v6dns = (const struct sockaddr_in6 *)addr;
186
187	if (memcmp(&v6->sin6_addr, &v6dns->sin6_addr, sizeof(struct in6_addr)) != 0)
188	{
189	sendheader(auth->client, REPORT_IP_MISMATCH);
190	good = 0;
191	}
192	}
193	else
194	#endif
195	{
196	v4 = (const struct sockaddr_in *)&auth->client->localClient->ip;
197	v4dns = (const struct sockaddr_in *)addr;
198
199	if (v4->sin_addr.s_addr != v4dns->sin_addr.s_addr)
200	{
201	sendheader(auth->client, REPORT_IP_MISMATCH);
202	good = 0;
203	}
204	}
205
206	if (good && strlen(name) <= HOSTLEN)
207	{
208	strlcpy(auth->client->host, name,
209	sizeof(auth->client->host));
210	sendheader(auth->client, REPORT_FIN_DNS);
211	}
212	else if (strlen(name) > HOSTLEN)
213	sendheader(auth->client, REPORT_HOST_TOOLONG);
214	}
215	else
216	sendheader(auth->client, REPORT_FAIL_DNS);
217
218	release_auth_client(auth);
219	}
220
221	/*
222	* authsenderr - handle auth send errors
223	*/
224	static void
225	auth_error(struct AuthRequest *auth)
226	{
227	++ServerStats.is_abad;
228
229	fd_close(&auth->fd);
230
231	ClearAuth(auth);
232
233	sendheader(auth->client, REPORT_FAIL_ID);
234
235	release_auth_client(auth);
236	}
237
238	/*
239	* start_auth_query - Flag the client to show that an attempt to
240	* contact the ident server on
241	* the client's host. The connect and subsequently the socket are all put
242	* into 'non-blocking' mode. Should the connect or any later phase of the
243	* identifing process fail, it is aborted and the user is given a username
244	* of "unknown".
245	*/
246	static int
247	start_auth_query(struct AuthRequest *auth)
248	{
249	struct irc_ssaddr localaddr;
250	socklen_t locallen = sizeof(struct irc_ssaddr);
251	#ifdef IPV6
252	struct sockaddr_in6 *v6;
253	#else
254	struct sockaddr_in *v4;
255	#endif
256
257	/* open a socket of the same type as the client socket */
258	if (comm_open(&auth->fd, auth->client->localClient->ip.ss.ss_family,
259	SOCK_STREAM, 0, "ident") == -1)
260	{
261	report_error(L_ALL, "creating auth stream socket %s:%s",
262	get_client_name(auth->client, SHOW_IP), errno);
263	ilog(LOG_TYPE_IRCD, "Unable to create auth socket for %s",
264	get_client_name(auth->client, SHOW_IP));
265	++ServerStats.is_abad;
266	return 0;
267	}
268
269	sendheader(auth->client, REPORT_DO_ID);
270
271	/*
272	* get the local address of the client and bind to that to
273	* make the auth request. This used to be done only for
274	* ifdef VIRTUAL_HOST, but needs to be done for all clients
275	* since the ident request must originate from that same address--
276	* and machines with multiple IP addresses are common now
277	*/
278	memset(&localaddr, 0, locallen);
279	getsockname(auth->client->localClient->fd.fd, (struct sockaddr*)&localaddr,
280	&locallen);
281
282	#ifdef IPV6
283	remove_ipv6_mapping(&localaddr);
284	v6 = (struct sockaddr_in6 *)&localaddr;
285	v6->sin6_port = htons(0);
286	#else
287	localaddr.ss_len = locallen;
288	v4 = (struct sockaddr_in *)&localaddr;
289	v4->sin_port = htons(0);
290	#endif
291	localaddr.ss_port = htons(0);
292
293	comm_connect_tcp(&auth->fd, auth->client->sockhost, 113,
294	(struct sockaddr *)&localaddr, localaddr.ss_len, auth_connect_callback,
295	auth, auth->client->localClient->ip.ss.ss_family,
296	GlobalSetOptions.ident_timeout);
297	return 1; /* We suceed here for now */
298	}
299
300	/*
301	* GetValidIdent - parse ident query reply from identd server
302	*
303	* Inputs - pointer to ident buf
304	* Output - NULL if no valid ident found, otherwise pointer to name
305	* Side effects -
306	*/
307	/*
308	* A few questions have been asked about this mess, obviously
309	* it should have been commented better the first time.
310	* The original idea was to remove all references to libc from ircd-hybrid.
311	* Instead of having to write a replacement for sscanf(), I did a
312	* rather gruseome parser here so we could remove this function call.
313	* Note, that I had also removed a few floating point printfs as well (though
314	* now we are still stuck with a few...)
315	* Remember, we have a replacement ircd sprintf, we have bleeps fputs lib
316	* it would have been nice to remove some unneeded code.
317	* Oh well. If we don't remove libc stuff totally, then it would be
318	* far cleaner to use sscanf()
319	*
320	* - Dianora
321	*/
322	static char *
323	GetValidIdent(char *buf)
324	{
325	int remp = 0;
326	int locp = 0;
327	char* colon1Ptr;
328	char* colon2Ptr;
329	char* colon3Ptr;
330	char* commaPtr;
331	char* remotePortString;
332
333	/* All this to get rid of a sscanf() fun. */
334	remotePortString = buf;
335
336	if ((colon1Ptr = strchr(remotePortString,':')) == NULL)
337	return 0;
338	*colon1Ptr = '\0';
339	colon1Ptr++;
340
341	if ((colon2Ptr = strchr(colon1Ptr,':')) == NULL)
342	return 0;
343	*colon2Ptr = '\0';
344	colon2Ptr++;
345
346	if ((commaPtr = strchr(remotePortString, ',')) == NULL)
347	return 0;
348	*commaPtr = '\0';
349	commaPtr++;
350
351	if ((remp = atoi(remotePortString)) == 0)
352	return 0;
353
354	if ((locp = atoi(commaPtr)) == 0)
355	return 0;
356
357	/* look for USERID bordered by first pair of colons */
358	if (strstr(colon1Ptr, "USERID") == NULL)
359	return 0;
360
361	if ((colon3Ptr = strchr(colon2Ptr,':')) == NULL)
362	return 0;
363	*colon3Ptr = '\0';
364	colon3Ptr++;
365	return (colon3Ptr);
366	}
367
368	/*
369	* start_auth
370	*
371	* inputs - pointer to client to auth
372	* output - NONE
373	* side effects - starts auth (identd) and dns queries for a client
374	*/
375	void
376	start_auth(struct Client *client_p)
377	{
378	struct AuthRequest *auth = NULL;
379
380	assert(client_p);
381
382	auth = make_auth_request(client_p);
383	SetInAuth(auth);
384	dlinkAddTail(auth, &auth->node, &auth_doing_list);
385
386	sendheader(client_p, REPORT_DO_DNS);
387
388	SetDNSPending(auth);
389
390	if (ConfigFileEntry.disable_auth == 0)
391	{
392	SetDoingAuth(auth);
393	start_auth_query(auth);
394	}
395
396	gethost_byaddr(auth_dns_callback, auth, &client_p->localClient->ip);
397	}
398
399	/*
400	* timeout_auth_queries - timeout resolver and identd requests
401	* allow clients through if requests failed
402	*/
403	static void
404	timeout_auth_queries_event(void *notused)
405	{
406	dlink_node ptr = NULL, ptr_next = NULL;
407
408	DLINK_FOREACH_SAFE(ptr, ptr_next, auth_doing_list.head)
409	{
410	struct AuthRequest *auth = ptr->data;
411
412	if (auth->timeout > CurrentTime)
413	break;
414
415	if (IsDoingAuth(auth))
416	{
417	++ServerStats.is_abad;
418	fd_close(&auth->fd);
419	ClearAuth(auth);
420	sendheader(auth->client, REPORT_FAIL_ID);
421	}
422
423	if (IsDNSPending(auth))
424	{
425	delete_resolver_queries(auth);
426	ClearDNSPending(auth);
427	sendheader(auth->client, REPORT_FAIL_DNS);
428	}
429
430	ilog(LOG_TYPE_IRCD, "DNS/AUTH timeout %s",
431	get_client_name(auth->client, SHOW_IP));
432	release_auth_client(auth);
433	}
434	}
435
436	/*
437	* auth_connect_callback() - deal with the result of comm_connect_tcp()
438	*
439	* If the connection failed, we simply close the auth fd and report
440	* a failure. If the connection suceeded send the ident server a query
441	* giving "theirport , ourport". The write is only attempted once so
442	* it is deemed to be a fail if the entire write doesn't write all the
443	* data given. This shouldnt be a problem since the socket should have
444	* a write buffer far greater than this message to store it in should
445	* problems arise. -avalon
446	*/
447	static void
448	auth_connect_callback(fde_t fd, int error, void data)
449	{
450	struct AuthRequest *auth = data;
451	struct irc_ssaddr us;
452	struct irc_ssaddr them;
453	char authbuf[32];
454	socklen_t ulen = sizeof(struct irc_ssaddr);
455	socklen_t tlen = sizeof(struct irc_ssaddr);
456	uint16_t uport, tport;
457	#ifdef IPV6
458	struct sockaddr_in6 *v6;
459	#else
460	struct sockaddr_in *v4;
461	#endif
462
463	if (error != COMM_OK)
464	{
465	auth_error(auth);
466	return;
467	}
468
469	if (getsockname(auth->client->localClient->fd.fd, (struct sockaddr *)&us, &ulen) \|\|
470	getpeername(auth->client->localClient->fd.fd, (struct sockaddr *)&them, &tlen))
471	{
472	ilog(LOG_TYPE_IRCD, "auth get{sock,peer}name error for %s",
473	get_client_name(auth->client, SHOW_IP));
474	auth_error(auth);
475	return;
476	}
477
478	#ifdef IPV6
479	v6 = (struct sockaddr_in6 *)&us;
480	uport = ntohs(v6->sin6_port);
481	v6 = (struct sockaddr_in6 *)&them;
482	tport = ntohs(v6->sin6_port);
483	remove_ipv6_mapping(&us);
484	remove_ipv6_mapping(&them);
485	#else
486	v4 = (struct sockaddr_in *)&us;
487	uport = ntohs(v4->sin_port);
488	v4 = (struct sockaddr_in *)&them;
489	tport = ntohs(v4->sin_port);
490	us.ss_len = ulen;
491	them.ss_len = tlen;
492	#endif
493
494	snprintf(authbuf, sizeof(authbuf), "%u , %u\r\n", tport, uport);
495
496	if (send(fd->fd, authbuf, strlen(authbuf), 0) == -1)
497	{
498	auth_error(auth);
499	return;
500	}
501
502	read_auth_reply(&auth->fd, auth);
503	}
504
505	/*
506	* read_auth_reply - read the reply (if any) from the ident server
507	* we connected to.
508	* We only give it one shot, if the reply isn't good the first time
509	* fail the authentication entirely. --Bleep
510	*/
511	#define AUTH_BUFSIZ 128
512
513	static void
514	read_auth_reply(fde_t fd, void data)
515	{
516	struct AuthRequest *auth = data;
517	char *s = NULL;
518	char *t = NULL;
519	int len;
520	int count;
521	char buf[AUTH_BUFSIZ + 1]; /* buffer to read auth reply into */
522
523	/* Why?
524	* Well, recv() on many POSIX systems is a per-packet operation,
525	* and we do not necessarily want this, because on lowspec machines,
526	* the ident response may come back fragmented, thus resulting in an
527	* invalid ident response, even if the ident response was really OK.
528	*
529	* So PLEASE do not change this code to recv without being aware of the
530	* consequences.
531	*
532	* --nenolod
533	*/
534	len = read(fd->fd, buf, AUTH_BUFSIZ);
535
536	if (len < 0)
537	{
538	if (ignoreErrno(errno))
539	comm_setselect(fd, COMM_SELECT_READ, read_auth_reply, auth, 0);
540	else
541	auth_error(auth);
542	return;
543	}
544
545	if (len > 0)
546	{
547	buf[len] = '\0';
548
549	if ((s = GetValidIdent(buf)))
550	{
551	t = auth->client->username;
552
553	while (s == '~' \|\| s == '^')
554	s++;
555
556	for (count = USERLEN; *s && count; s++)
557	{
558	if (*s == '@')
559	break;
560	if (!IsSpace(s) && s != ':')
561	{
562	t++ = s;
563	count--;
564	}
565	}
566
567	*t = '\0';
568	}
569	}
570
571	fd_close(fd);
572
573	ClearAuth(auth);
574
575	if (s == NULL)
576	{
577	sendheader(auth->client, REPORT_FAIL_ID);
578	++ServerStats.is_abad;
579	}
580	else
581	{
582	sendheader(auth->client, REPORT_FIN_ID);
583	++ServerStats.is_asuc;
584	SetGotId(auth->client);
585	}
586
587	release_auth_client(auth);
588	}
589
590	/*
591	* delete_auth()
592	*/
593	void
594	delete_auth(struct AuthRequest *auth)
595	{
596	if (IsDNSPending(auth))
597	delete_resolver_queries(auth);
598
599	if (IsDoingAuth(auth))
600	fd_close(&auth->fd);
601
602	if (IsInAuth(auth))
603	{
604	dlinkDelete(&auth->node, &auth_doing_list);
605	ClearInAuth(auth);
606	}
607	}