trunk/src/s_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 s_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 "s_auth.h"
#include "conf.h"
#include "client.h"
#include "event.h"
#include "hook.h"
#include "irc_string.h"
#include "ircd.h"
#include "packet.h"
#include "irc_res.h"
#include "s_bsd.h"
#include "log.h"
#include "send.h"
#include "mempool.h"


static const char *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 EVH timeout_auth_queries_event;

static PF read_auth_reply;
static CNCB auth_connect_callback;

/* auth_init
 *
 * Initialise the auth code
 */
void
auth_init(void)
{
  eventAddIsh("timeout_auth_queries_event", timeout_auth_queries_event, NULL, 1);
}

/*
 * 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 != NULL)
  {
    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)
{
  struct AuthRequest *auth = NULL;

  assert(client != NULL);

  auth = make_auth_request(client);
  SetInAuth(auth);
  dlinkAddTail(auth, &auth->node, &auth_doing_list);

  sendheader(client, REPORT_DO_DNS);

  SetDNSPending(auth);

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

  gethost_byaddr(auth_dns_callback, auth, &client->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, *next_ptr = NULL;

  DLINK_FOREACH_SAFE(ptr, next_ptr, 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 != ':' && *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:	3168
Committed:	Sat Mar 15 23:46:08 2014 UTC (11 years, 5 months ago) by michael
Content type:	text/x-csrc
File size:	15131 byte(s)
Log Message:	- s_auth.c: made sendheader macro use sendto_one_notice()
#	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 s_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 "s_auth.h"
43	#include "conf.h"
44	#include "client.h"
45	#include "event.h"
46	#include "hook.h"
47	#include "irc_string.h"
48	#include "ircd.h"
49	#include "packet.h"
50	#include "irc_res.h"
51	#include "s_bsd.h"
52	#include "log.h"
53	#include "send.h"
54	#include "mempool.h"
55
56
57	static const char *HeaderMessages[] =
58	{
59	":*** Looking up your hostname...",
60	":*** Found your hostname",
61	":*** Couldn't look up your hostname",
62	":*** Checking Ident",
63	":*** Got Ident response",
64	":*** No Ident response",
65	":*** Your forward and reverse DNS do not match, ignoring hostname.",
66	":*** Your hostname is too long, ignoring hostname"
67	};
68
69	enum
70	{
71	REPORT_DO_DNS,
72	REPORT_FIN_DNS,
73	REPORT_FAIL_DNS,
74	REPORT_DO_ID,
75	REPORT_FIN_ID,
76	REPORT_FAIL_ID,
77	REPORT_IP_MISMATCH,
78	REPORT_HOST_TOOLONG
79	};
80
81	#define sendheader(c, i) sendto_one_notice((c), &me, HeaderMessages[(i)])
82
83	static dlink_list auth_doing_list = { NULL, NULL, 0 };
84
85	static EVH timeout_auth_queries_event;
86
87	static PF read_auth_reply;
88	static CNCB auth_connect_callback;
89
90	/* auth_init
91	*
92	* Initialise the auth code
93	*/
94	void
95	auth_init(void)
96	{
97	eventAddIsh("timeout_auth_queries_event", timeout_auth_queries_event, NULL, 1);
98	}
99
100	/*
101	* make_auth_request - allocate a new auth request
102	*/
103	static struct AuthRequest *
104	make_auth_request(struct Client *client)
105	{
106	struct AuthRequest *request = &client->localClient->auth;
107
108	memset(request, 0, sizeof(*request));
109
110	request->client = client;
111	request->timeout = CurrentTime + CONNECTTIMEOUT;
112
113	return request;
114	}
115
116	/*
117	* release_auth_client - release auth client from auth system
118	* this adds the client into the local client lists so it can be read by
119	* the main io processing loop
120	*/
121	void
122	release_auth_client(struct AuthRequest *auth)
123	{
124	struct Client *client = auth->client;
125
126	if (IsDoingAuth(auth) \|\| IsDNSPending(auth))
127	return;
128
129	if (IsInAuth(auth))
130	{
131	dlinkDelete(&auth->node, &auth_doing_list);
132	ClearInAuth(auth);
133	}
134
135	/*
136	* When a client has auth'ed, we want to start reading what it sends
137	* us. This is what read_packet() does.
138	* -- adrian
139	*/
140	client->localClient->allow_read = MAX_FLOOD;
141	comm_setflush(&client->localClient->fd, 1000, flood_recalc, client);
142
143	dlinkAdd(client, &client->node, &global_client_list);
144
145	client->localClient->since = CurrentTime;
146	client->localClient->lasttime = CurrentTime;
147	client->localClient->firsttime = CurrentTime;
148	client->flags \|= FLAGS_FINISHED_AUTH;
149
150	read_packet(&client->localClient->fd, client);
151	}
152
153	/*
154	* auth_dns_callback - called when resolver query finishes
155	* if the query resulted in a successful search, name will contain
156	* a non-NULL pointer, otherwise name will be NULL.
157	* set the client on it's way to a connection completion, regardless
158	* of success of failure
159	*/
160	static void
161	auth_dns_callback(void vptr, const struct irc_ssaddr addr, const char *name)
162	{
163	struct AuthRequest *auth = vptr;
164
165	ClearDNSPending(auth);
166
167	if (name != NULL)
168	{
169	const struct sockaddr_in v4, v4dns;
170	#ifdef IPV6
171	const struct sockaddr_in6 v6, v6dns;
172	#endif
173	int good = 1;
174
175	#ifdef IPV6
176	if (auth->client->localClient->ip.ss.ss_family == AF_INET6)
177	{
178	v6 = (const struct sockaddr_in6 *)&auth->client->localClient->ip;
179	v6dns = (const struct sockaddr_in6 *)addr;
180	if (memcmp(&v6->sin6_addr, &v6dns->sin6_addr, sizeof(struct in6_addr)) != 0)
181	{
182	sendheader(auth->client, REPORT_IP_MISMATCH);
183	good = 0;
184	}
185	}
186	else
187	#endif
188	{
189	v4 = (const struct sockaddr_in *)&auth->client->localClient->ip;
190	v4dns = (const struct sockaddr_in *)addr;
191	if(v4->sin_addr.s_addr != v4dns->sin_addr.s_addr)
192	{
193	sendheader(auth->client, REPORT_IP_MISMATCH);
194	good = 0;
195	}
196	}
197	if (good && strlen(name) <= HOSTLEN)
198	{
199	strlcpy(auth->client->host, name,
200	sizeof(auth->client->host));
201	sendheader(auth->client, REPORT_FIN_DNS);
202	}
203	else if (strlen(name) > HOSTLEN)
204	sendheader(auth->client, REPORT_HOST_TOOLONG);
205	}
206	else
207	sendheader(auth->client, REPORT_FAIL_DNS);
208
209	release_auth_client(auth);
210	}
211
212	/*
213	* authsenderr - handle auth send errors
214	*/
215	static void
216	auth_error(struct AuthRequest *auth)
217	{
218	++ServerStats.is_abad;
219
220	fd_close(&auth->fd);
221
222	ClearAuth(auth);
223
224	sendheader(auth->client, REPORT_FAIL_ID);
225
226	release_auth_client(auth);
227	}
228
229	/*
230	* start_auth_query - Flag the client to show that an attempt to
231	* contact the ident server on
232	* the client's host. The connect and subsequently the socket are all put
233	* into 'non-blocking' mode. Should the connect or any later phase of the
234	* identifing process fail, it is aborted and the user is given a username
235	* of "unknown".
236	*/
237	static int
238	start_auth_query(struct AuthRequest *auth)
239	{
240	struct irc_ssaddr localaddr;
241	socklen_t locallen = sizeof(struct irc_ssaddr);
242	#ifdef IPV6
243	struct sockaddr_in6 *v6;
244	#else
245	struct sockaddr_in *v4;
246	#endif
247
248	/* open a socket of the same type as the client socket */
249	if (comm_open(&auth->fd, auth->client->localClient->ip.ss.ss_family,
250	SOCK_STREAM, 0, "ident") == -1)
251	{
252	report_error(L_ALL, "creating auth stream socket %s:%s",
253	get_client_name(auth->client, SHOW_IP), errno);
254	ilog(LOG_TYPE_IRCD, "Unable to create auth socket for %s",
255	get_client_name(auth->client, SHOW_IP));
256	++ServerStats.is_abad;
257	return 0;
258	}
259
260	sendheader(auth->client, REPORT_DO_ID);
261
262	/*
263	* get the local address of the client and bind to that to
264	* make the auth request. This used to be done only for
265	* ifdef VIRTUAL_HOST, but needs to be done for all clients
266	* since the ident request must originate from that same address--
267	* and machines with multiple IP addresses are common now
268	*/
269	memset(&localaddr, 0, locallen);
270	getsockname(auth->client->localClient->fd.fd, (struct sockaddr*)&localaddr,
271	&locallen);
272
273	#ifdef IPV6
274	remove_ipv6_mapping(&localaddr);
275	v6 = (struct sockaddr_in6 *)&localaddr;
276	v6->sin6_port = htons(0);
277	#else
278	localaddr.ss_len = locallen;
279	v4 = (struct sockaddr_in *)&localaddr;
280	v4->sin_port = htons(0);
281	#endif
282	localaddr.ss_port = htons(0);
283
284	comm_connect_tcp(&auth->fd, auth->client->sockhost, 113,
285	(struct sockaddr *)&localaddr, localaddr.ss_len, auth_connect_callback,
286	auth, auth->client->localClient->ip.ss.ss_family,
287	GlobalSetOptions.ident_timeout);
288	return 1; /* We suceed here for now */
289	}
290
291	/*
292	* GetValidIdent - parse ident query reply from identd server
293	*
294	* Inputs - pointer to ident buf
295	* Output - NULL if no valid ident found, otherwise pointer to name
296	* Side effects -
297	*/
298	/*
299	* A few questions have been asked about this mess, obviously
300	* it should have been commented better the first time.
301	* The original idea was to remove all references to libc from ircd-hybrid.
302	* Instead of having to write a replacement for sscanf(), I did a
303	* rather gruseome parser here so we could remove this function call.
304	* Note, that I had also removed a few floating point printfs as well (though
305	* now we are still stuck with a few...)
306	* Remember, we have a replacement ircd sprintf, we have bleeps fputs lib
307	* it would have been nice to remove some unneeded code.
308	* Oh well. If we don't remove libc stuff totally, then it would be
309	* far cleaner to use sscanf()
310	*
311	* - Dianora
312	*/
313	static char *
314	GetValidIdent(char *buf)
315	{
316	int remp = 0;
317	int locp = 0;
318	char* colon1Ptr;
319	char* colon2Ptr;
320	char* colon3Ptr;
321	char* commaPtr;
322	char* remotePortString;
323
324	/* All this to get rid of a sscanf() fun. */
325	remotePortString = buf;
326
327	if ((colon1Ptr = strchr(remotePortString,':')) == NULL)
328	return 0;
329	*colon1Ptr = '\0';
330	colon1Ptr++;
331
332	if ((colon2Ptr = strchr(colon1Ptr,':')) == NULL)
333	return 0;
334	*colon2Ptr = '\0';
335	colon2Ptr++;
336
337	if ((commaPtr = strchr(remotePortString, ',')) == NULL)
338	return 0;
339	*commaPtr = '\0';
340	commaPtr++;
341
342	if ((remp = atoi(remotePortString)) == 0)
343	return 0;
344
345	if ((locp = atoi(commaPtr)) == 0)
346	return 0;
347
348	/* look for USERID bordered by first pair of colons */
349	if (strstr(colon1Ptr, "USERID") == NULL)
350	return 0;
351
352	if ((colon3Ptr = strchr(colon2Ptr,':')) == NULL)
353	return 0;
354	*colon3Ptr = '\0';
355	colon3Ptr++;
356	return (colon3Ptr);
357	}
358
359	/*
360	* start_auth
361	*
362	* inputs - pointer to client to auth
363	* output - NONE
364	* side effects - starts auth (identd) and dns queries for a client
365	*/
366	void
367	start_auth(struct Client *client)
368	{
369	struct AuthRequest *auth = NULL;
370
371	assert(client != NULL);
372
373	auth = make_auth_request(client);
374	SetInAuth(auth);
375	dlinkAddTail(auth, &auth->node, &auth_doing_list);
376
377	sendheader(client, REPORT_DO_DNS);
378
379	SetDNSPending(auth);
380
381	if (ConfigFileEntry.disable_auth == 0)
382	{
383	SetDoingAuth(auth);
384	start_auth_query(auth);
385	}
386
387	gethost_byaddr(auth_dns_callback, auth, &client->localClient->ip);
388	}
389
390	/*
391	* timeout_auth_queries - timeout resolver and identd requests
392	* allow clients through if requests failed
393	*/
394	static void
395	timeout_auth_queries_event(void *notused)
396	{
397	dlink_node ptr = NULL, next_ptr = NULL;
398
399	DLINK_FOREACH_SAFE(ptr, next_ptr, auth_doing_list.head)
400	{
401	struct AuthRequest *auth = ptr->data;
402
403	if (auth->timeout > CurrentTime)
404	break;
405
406	if (IsDoingAuth(auth))
407	{
408	++ServerStats.is_abad;
409	fd_close(&auth->fd);
410	ClearAuth(auth);
411	sendheader(auth->client, REPORT_FAIL_ID);
412	}
413
414	if (IsDNSPending(auth))
415	{
416	delete_resolver_queries(auth);
417	ClearDNSPending(auth);
418	sendheader(auth->client, REPORT_FAIL_DNS);
419	}
420
421	ilog(LOG_TYPE_IRCD, "DNS/AUTH timeout %s",
422	get_client_name(auth->client, SHOW_IP));
423	release_auth_client(auth);
424	}
425	}
426
427	/*
428	* auth_connect_callback() - deal with the result of comm_connect_tcp()
429	*
430	* If the connection failed, we simply close the auth fd and report
431	* a failure. If the connection suceeded send the ident server a query
432	* giving "theirport , ourport". The write is only attempted once so
433	* it is deemed to be a fail if the entire write doesn't write all the
434	* data given. This shouldnt be a problem since the socket should have
435	* a write buffer far greater than this message to store it in should
436	* problems arise. -avalon
437	*/
438	static void
439	auth_connect_callback(fde_t fd, int error, void data)
440	{
441	struct AuthRequest *auth = data;
442	struct irc_ssaddr us;
443	struct irc_ssaddr them;
444	char authbuf[32];
445	socklen_t ulen = sizeof(struct irc_ssaddr);
446	socklen_t tlen = sizeof(struct irc_ssaddr);
447	uint16_t uport, tport;
448	#ifdef IPV6
449	struct sockaddr_in6 *v6;
450	#else
451	struct sockaddr_in *v4;
452	#endif
453
454	if (error != COMM_OK)
455	{
456	auth_error(auth);
457	return;
458	}
459
460	if (getsockname(auth->client->localClient->fd.fd, (struct sockaddr *)&us,
461	&ulen) \|\|
462	getpeername(auth->client->localClient->fd.fd, (struct sockaddr *)&them,
463	&tlen))
464	{
465	ilog(LOG_TYPE_IRCD, "auth get{sock,peer}name error for %s",
466	get_client_name(auth->client, SHOW_IP));
467	auth_error(auth);
468	return;
469	}
470
471	#ifdef IPV6
472	v6 = (struct sockaddr_in6 *)&us;
473	uport = ntohs(v6->sin6_port);
474	v6 = (struct sockaddr_in6 *)&them;
475	tport = ntohs(v6->sin6_port);
476	remove_ipv6_mapping(&us);
477	remove_ipv6_mapping(&them);
478	#else
479	v4 = (struct sockaddr_in *)&us;
480	uport = ntohs(v4->sin_port);
481	v4 = (struct sockaddr_in *)&them;
482	tport = ntohs(v4->sin_port);
483	us.ss_len = ulen;
484	them.ss_len = tlen;
485	#endif
486
487	snprintf(authbuf, sizeof(authbuf), "%u , %u\r\n", tport, uport);
488
489	if (send(fd->fd, authbuf, strlen(authbuf), 0) == -1)
490	{
491	auth_error(auth);
492	return;
493	}
494
495	read_auth_reply(&auth->fd, auth);
496	}
497
498	/*
499	* read_auth_reply - read the reply (if any) from the ident server
500	* we connected to.
501	* We only give it one shot, if the reply isn't good the first time
502	* fail the authentication entirely. --Bleep
503	*/
504	#define AUTH_BUFSIZ 128
505
506	static void
507	read_auth_reply(fde_t fd, void data)
508	{
509	struct AuthRequest *auth = data;
510	char *s = NULL;
511	char *t = NULL;
512	int len;
513	int count;
514	char buf[AUTH_BUFSIZ + 1]; /* buffer to read auth reply into */
515
516	/* Why?
517	* Well, recv() on many POSIX systems is a per-packet operation,
518	* and we do not necessarily want this, because on lowspec machines,
519	* the ident response may come back fragmented, thus resulting in an
520	* invalid ident response, even if the ident response was really OK.
521	*
522	* So PLEASE do not change this code to recv without being aware of the
523	* consequences.
524	*
525	* --nenolod
526	*/
527	len = read(fd->fd, buf, AUTH_BUFSIZ);
528
529	if (len < 0)
530	{
531	if (ignoreErrno(errno))
532	comm_setselect(fd, COMM_SELECT_READ, read_auth_reply, auth, 0);
533	else
534	auth_error(auth);
535	return;
536	}
537
538	if (len > 0)
539	{
540	buf[len] = '\0';
541
542	if ((s = GetValidIdent(buf)))
543	{
544	t = auth->client->username;
545
546	while (s == '~' \|\| s == '^')
547	s++;
548
549	for (count = USERLEN; *s && count; s++)
550	{
551	if (*s == '@')
552	break;
553	if (!IsSpace(s) && s != ':' && *s != '[')
554	{
555	t++ = s;
556	count--;
557	}
558	}
559
560	*t = '\0';
561	}
562	}
563
564	fd_close(fd);
565
566	ClearAuth(auth);
567
568	if (s == NULL)
569	{
570	sendheader(auth->client, REPORT_FAIL_ID);
571	++ServerStats.is_abad;
572	}
573	else
574	{
575	sendheader(auth->client, REPORT_FIN_ID);
576	++ServerStats.is_asuc;
577	SetGotId(auth->client);
578	}
579
580	release_auth_client(auth);
581	}
582
583	/*
584	* delete_auth()
585	*/
586	void
587	delete_auth(struct AuthRequest *auth)
588	{
589	if (IsDNSPending(auth))
590	delete_resolver_queries(auth);
591
592	if (IsDoingAuth(auth))
593	fd_close(&auth->fd);
594
595	if (IsInAuth(auth))
596	{
597	dlinkDelete(&auth->node, &auth_doing_list);
598	ClearInAuth(auth);
599	}
600	}