modules/m_sasl.c

   1 /* modules/m_sasl.c
   2  *   Copyright (C) 2006 Michael Tharp <gxti@partiallystapled.com>
   3  *   Copyright (C) 2006 charybdis development team
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met:
   8  *
   9  * 1.Redistributions of source code must retain the above copyright notice,
  10  *   this list of conditions and the following disclaimer.
  11  * 2.Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * 3.The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  21  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  25  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  26  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  27  * POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  * $Id: m_sasl.c 1409 2006-05-21 14:46:17Z jilles $
  30  */
  31
  32 #include "stdinc.h"
  33
  34 #include "client.h"
  35 #include "hash.h"
  36 #include "send.h"
  37 #include "msg.h"
  38 #include "modules.h"
  39 #include "numeric.h"
  40 #include "s_serv.h"
  41 #include "s_stats.h"
  42 #include "string.h"
  43
  44 static int mr_authenticate(struct Client *, struct Client *, int, const char **);
  45 static int me_sasl(struct Client *, struct Client *, int, const char **);
  46
  47 static void abort_sasl(struct Client *);
  48 static void abort_sasl_exit(hook_data_client_exit *);
  49
  50 struct Message authenticate_msgtab = {
  51         "AUTHENTICATE", 0, 0, 0, MFLG_SLOW,
  52         {{mr_authenticate, 2}, mg_reg, mg_ignore, mg_ignore, mg_ignore, mg_reg}
  53 };
  54 struct Message sasl_msgtab = {
  55         "SASL", 0, 0, 0, MFLG_SLOW,
  56         {mg_ignore, mg_ignore, mg_ignore, mg_ignore, {me_sasl, 5}, mg_ignore}
  57 };
  58
  59 mapi_clist_av1 sasl_clist[] = {
  60         &authenticate_msgtab, &sasl_msgtab, NULL
  61 };
  62 mapi_hfn_list_av1 sasl_hfnlist[] = {
  63         { "new_local_user",     (hookfn) abort_sasl },
  64         { "client_exit",        (hookfn) abort_sasl_exit },
  65         { NULL, NULL }
  66 };
  67
  68 DECLARE_MODULE_AV1(sasl, NULL, NULL, sasl_clist, NULL, sasl_hfnlist, "$Revision: 1409 $");
  69
  70 static int
  71 mr_authenticate(struct Client *client_p, struct Client *source_p,
  72         int parc, const char *parv[])
  73 {
  74         struct Client *agent_p = NULL;
  75
  76         /* They really should use CAP for their own sake. */
  77         if(!IsCapable(source_p, CLICAP_SASL))
  78                 return 0;
  79
  80         if (strlen(client_p->id) == 3)
  81         {
  82                 exit_client(client_p, client_p, client_p, "Mixing client and server protocol");
  83                 return 0;
  84         }
  85
  86         if(source_p->preClient->sasl_complete)
  87         {
  88                 sendto_one(source_p, form_str(ERR_SASLALREADY), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
  89                 return 0;
  90         }
  91
  92         if(strlen(parv[1]) > 400)
  93         {
  94                 sendto_one(source_p, form_str(ERR_SASLTOOLONG), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
  95                 return 0;
  96         }
  97
  98         if(!*source_p->id)
  99         {
 100                 /* Allocate a UID. */
 101                 strcpy(source_p->id, generate_uid());
 102                 add_to_id_hash(source_p->id, source_p);
 103         }
 104
 105         if(*source_p->preClient->sasl_agent)
 106                 agent_p = find_id(source_p->preClient->sasl_agent);
 107
 108         if(agent_p == NULL)
 109                 sendto_server(NULL, NULL, CAP_TS6|CAP_ENCAP, NOCAPS, ":%s ENCAP * SASL %s * S %s", me.id,
 110                                 source_p->id, parv[1]);
 111         else
 112                 sendto_one(agent_p, ":%s ENCAP %s SASL %s %s C %s", me.id, agent_p->servptr->name,
 113                                 source_p->id, agent_p->id, parv[1]);
 114         source_p->preClient->sasl_out++;
 115
 116         return 0;
 117 }
 118
 119 static int
 120 me_sasl(struct Client *client_p, struct Client *source_p,
 121         int parc, const char *parv[])
 122 {
 123         struct Client *target_p, *agent_p;
 124
 125         /* Let propagate if not addressed to us, or if broadcast.
 126          * Only SASL agents can answer global requests.
 127          */
 128         if(strncmp(parv[2], me.id, 3))
 129                 return 0;
 130
 131         if((target_p = find_id(parv[2])) == NULL)
 132                 return 0;
 133
 134         if(target_p->preClient == NULL)
 135                 return 0;
 136
 137         if((agent_p = find_id(parv[1])) == NULL)
 138                 return 0;
 139
 140         if(source_p != agent_p->servptr) /* WTF?! */
 141                 return 0;
 142
 143         /* We only accept messages from SASL agents; these must have umode +S
 144          * (so the server must be listed in a service{} block).
 145          */
 146         if(!IsService(agent_p))
 147                 return 0;
 148
 149         /* Reject if someone has already answered. */
 150         if(*target_p->preClient->sasl_agent && strncmp(parv[1], target_p->preClient->sasl_agent, IDLEN))
 151                 return 0;
 152         else if(!*target_p->preClient->sasl_agent)
 153                 rb_strlcpy(target_p->preClient->sasl_agent, parv[1], IDLEN);
 154
 155         if(*parv[3] == 'C')
 156                 sendto_one(target_p, "AUTHENTICATE %s", parv[4]);
 157         else if(*parv[3] == 'D')
 158         {
 159                 if(*parv[4] == 'F')
 160                         sendto_one(target_p, form_str(ERR_SASLFAIL), me.name, EmptyString(target_p->name) ? "*" : target_p->name);
 161                 else if(*parv[4] == 'S') {
 162                         sendto_one(target_p, form_str(RPL_SASLSUCCESS), me.name, EmptyString(target_p->name) ? "*" : target_p->name);
 163                         target_p->preClient->sasl_complete = 1;
 164                         ServerStats.is_ssuc++;
 165                 }
 166                 *target_p->preClient->sasl_agent = '\0'; /* Blank the stored agent so someone else can answer */
 167         }
 168
 169         return 0;
 170 }
 171
 172 /* If the client never finished authenticating but is
 173  * registering anyway, abort the exchange.
 174  */
 175 static void
 176 abort_sasl(struct Client *data)
 177 {
 178         if(data->preClient->sasl_out == 0 || data->preClient->sasl_complete)
 179                 return;
 180
 181         data->preClient->sasl_out = data->preClient->sasl_complete = 0;
 182         ServerStats.is_sbad++;
 183
 184         if(!IsClosing(data))
 185                 sendto_one(data, form_str(ERR_SASLABORTED), me.name, EmptyString(data->name) ? "*" : data->name);
 186
 187         if(*data->preClient->sasl_agent)
 188         {
 189                 struct Client *agent_p = find_id(data->preClient->sasl_agent);
 190                 if(agent_p)
 191                 {
 192                         sendto_one(agent_p, ":%s ENCAP %s SASL %s %s D A", me.id, agent_p->servptr->name,
 193                                         data->id, agent_p->id);
 194                         return;
 195                 }
 196         }
 197
 198         sendto_server(NULL, NULL, CAP_TS6|CAP_ENCAP, NOCAPS, ":%s ENCAP * SASL %s * D A", me.id,
 199                         data->id);
 200 }
 201
 202 static void
 203 abort_sasl_exit(hook_data_client_exit *data)
 204 {
 205         if (data->target->preClient)
 206                 abort_sasl(data->target);
 207 }
 208