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
  30 #include "stdinc.h"
  31
  32 #include "client.h"
  33 #include "hash.h"
  34 #include "send.h"
  35 #include "msg.h"
  36 #include "modules.h"
  37 #include "numeric.h"
  38 #include "s_serv.h"
  39 #include "s_stats.h"
  40 #include "string.h"
  41
  42 static int mr_authenticate(struct Client *, struct Client *, int, const char **);
  43 static int me_sasl(struct Client *, struct Client *, int, const char **);
  44
  45 static void abort_sasl(struct Client *);
  46 static void abort_sasl_exit(hook_data_client_exit *);
  47
  48 struct Message authenticate_msgtab = {
  49         "AUTHENTICATE", 0, 0, 0, MFLG_SLOW,
  50         {{mr_authenticate, 2}, mg_reg, mg_ignore, mg_ignore, mg_ignore, mg_reg}
  51 };
  52 struct Message sasl_msgtab = {
  53         "SASL", 0, 0, 0, MFLG_SLOW,
  54         {mg_ignore, mg_ignore, mg_ignore, mg_ignore, {me_sasl, 5}, mg_ignore}
  55 };
  56
  57 mapi_clist_av1 sasl_clist[] = {
  58         &authenticate_msgtab, &sasl_msgtab, NULL
  59 };
  60 mapi_hfn_list_av1 sasl_hfnlist[] = {
  61         { "new_local_user",     (hookfn) abort_sasl },
  62         { "client_exit",        (hookfn) abort_sasl_exit },
  63         { NULL, NULL }
  64 };
  65
  66 DECLARE_MODULE_AV1(sasl, NULL, NULL, sasl_clist, NULL, sasl_hfnlist, "$Revision: 26 $");
  67
  68 static int
  69 mr_authenticate(struct Client *client_p, struct Client *source_p,
  70         int parc, const char *parv[])
  71 {
  72         struct Client *agent_p = NULL;
  73
  74         /* They really should use CAP for their own sake. */
  75         if(!IsCapable(source_p, CLICAP_SASL))
  76                 return 0;
  77
  78         if (strlen(client_p->id) == 3)
  79         {
  80                 exit_client(client_p, client_p, client_p, "Mixing client and server protocol");
  81                 return 0;
  82         }
  83
  84         if(source_p->preClient->sasl_complete)
  85         {
  86                 sendto_one(source_p, form_str(ERR_SASLALREADY), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
  87                 return 0;
  88         }
  89
  90         if(strlen(parv[1]) > 400)
  91         {
  92                 sendto_one(source_p, form_str(ERR_SASLTOOLONG), me.name, EmptyString(source_p->name) ? "*" : source_p->name);
  93                 return 0;
  94         }
  95
  96         if(!*source_p->id)
  97         {
  98                 /* Allocate a UID. */
  99                 strcpy(source_p->id, generate_uid());
 100                 add_to_id_hash(source_p->id, source_p);
 101         }
 102
 103         if(*source_p->preClient->sasl_agent)
 104                 agent_p = find_id(source_p->preClient->sasl_agent);
 105
 106         if(agent_p == NULL)
 107                 sendto_server(NULL, NULL, CAP_TS6|CAP_ENCAP, NOCAPS, ":%s ENCAP * SASL %s * S %s", me.id,
 108                                 source_p->id, parv[1]);
 109         else
 110                 sendto_one(agent_p, ":%s ENCAP %s SASL %s %s C %s", me.id, agent_p->servptr->name,
 111                                 source_p->id, agent_p->id, parv[1]);
 112         source_p->preClient->sasl_out++;
 113
 114         return 0;
 115 }
 116
 117 static int
 118 me_sasl(struct Client *client_p, struct Client *source_p,
 119         int parc, const char *parv[])
 120 {
 121         struct Client *target_p, *agent_p;
 122
 123         /* Let propagate if not addressed to us, or if broadcast.
 124          * Only SASL agents can answer global requests.
 125          */
 126         if(strncmp(parv[2], me.id, 3))
 127                 return 0;
 128
 129         if((target_p = find_id(parv[2])) == NULL)
 130                 return 0;
 131
 132         if(target_p->preClient == NULL)
 133                 return 0;
 134
 135         if((agent_p = find_id(parv[1])) == NULL)
 136                 return 0;
 137
 138         if(source_p != agent_p->servptr) /* WTF?! */
 139                 return 0;
 140
 141         /* We only accept messages from SASL agents; these must have umode +S
 142          * (so the server must be listed in a service{} block).
 143          */
 144         if(!IsService(agent_p))
 145                 return 0;
 146
 147         /* Reject if someone has already answered. */
 148         if(*target_p->preClient->sasl_agent && strncmp(parv[1], target_p->preClient->sasl_agent, IDLEN))
 149                 return 0;
 150         else if(!*target_p->preClient->sasl_agent)
 151                 strlcpy(target_p->preClient->sasl_agent, parv[1], IDLEN);
 152
 153         if(*parv[3] == 'C')
 154                 sendto_one(target_p, "AUTHENTICATE %s", parv[4]);
 155         else if(*parv[3] == 'D')
 156         {
 157                 if(*parv[4] == 'F')
 158                         sendto_one(target_p, form_str(ERR_SASLFAIL), me.name, EmptyString(target_p->name) ? "*" : target_p->name);
 159                 else if(*parv[4] == 'S') {
 160                         sendto_one(target_p, form_str(RPL_SASLSUCCESS), me.name, EmptyString(target_p->name) ? "*" : target_p->name);
 161                         target_p->preClient->sasl_complete = 1;
 162                         ServerStats->is_ssuc++;
 163                 }
 164                 *target_p->preClient->sasl_agent = '\0'; /* Blank the stored agent so someone else can answer */
 165         }
 166
 167         return 0;
 168 }
 169
 170 /* If the client never finished authenticating but is
 171  * registering anyway, abort the exchange.
 172  */
 173 static void
 174 abort_sasl(struct Client *data)
 175 {
 176         if(data->preClient->sasl_out == 0 || data->preClient->sasl_complete)
 177                 return;
 178
 179         data->preClient->sasl_out = data->preClient->sasl_complete = 0;
 180         ServerStats->is_sbad++;
 181
 182         if(!IsClosing(data))
 183                 sendto_one(data, form_str(ERR_SASLABORTED), me.name, EmptyString(data->name) ? "*" : data->name);
 184
 185         if(*data->preClient->sasl_agent)
 186         {
 187                 struct Client *agent_p = find_id(data->preClient->sasl_agent);
 188                 if(agent_p)
 189                 {
 190                         sendto_one(agent_p, ":%s ENCAP %s SASL %s %s D A", me.id, agent_p->servptr->name,
 191                                         data->id, agent_p->id);
 192                         return;
 193                 }
 194         }
 195
 196         sendto_server(NULL, NULL, CAP_TS6|CAP_ENCAP, NOCAPS, ":%s ENCAP * SASL %s * D A", me.id,
 197                         data->id);
 198 }
 199
 200 static void
 201 abort_sasl_exit(hook_data_client_exit *data)
 202 {
 203         if (data->target->preClient)
 204                 abort_sasl(data->target);
 205 }
 206