citadel/dynloader.c

   1 /*
   2  * $Id$
   3  *
   4  * Citadel Dynamic Loading Module
   5  * Written by Brian Costello <btx@calyx.net>
   6  *
   7  */
   8
   9 #ifdef DLL_EXPORT
  10 #define IN_LIBCIT
  11 #endif
  12
  13 #include "sysdep.h"
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #ifdef HAVE_DLFCN_H
  17 #include <dlfcn.h>
  18 #endif
  19 #ifdef HAVE_DL_H
  20 #include <dl.h>
  21 #include "hpsux.h"
  22 #endif
  23 #include <sys/types.h>
  24 #include <dirent.h>
  25 #include <string.h>
  26 #include <syslog.h>
  27 #include <limits.h>
  28 #include <ctype.h>
  29 #include "citadel.h"
  30 #include "server.h"
  31 #include "dynloader.h"
  32 #include "sysdep_decls.h"
  33 #include "msgbase.h"
  34 #include "tools.h"
  35 #include "config.h"
  36
  37 #ifndef HAVE_SNPRINTF
  38 #include <stdarg.h>
  39 #include "snprintf.h"
  40 #endif
  41
  42 struct LogFunctionHook *LogHookTable = NULL;
  43 struct CleanupFunctionHook *CleanupHookTable = NULL;
  44 struct SessionFunctionHook *SessionHookTable = NULL;
  45 struct UserFunctionHook *UserHookTable = NULL;
  46 struct XmsgFunctionHook *XmsgHookTable = NULL;
  47 struct MessageFunctionHook *MessageHookTable = NULL;
  48 struct ServiceFunctionHook *ServiceHookTable = NULL;
  49
  50 struct ProtoFunctionHook {
  51         void (*handler) (char *cmdbuf);
  52         char *cmd;
  53         char *desc;
  54         struct ProtoFunctionHook *next;
  55 } *ProtoHookList = NULL;
  56
  57 void CtdlRegisterProtoHook(void (*handler) (char *), char *cmd, char *desc)
  58 {
  59         struct ProtoFunctionHook *p = mallok(sizeof *p);
  60
  61         if (p == NULL) {
  62                 fprintf(stderr, "can't malloc new ProtoFunctionHook\n");
  63                 exit(EXIT_FAILURE);
  64         }
  65         p->handler = handler;
  66         p->cmd = cmd;
  67         p->desc = desc;
  68         p->next = ProtoHookList;
  69         ProtoHookList = p;
  70         lprintf(5, "Registered server command %s (%s)\n", cmd, desc);
  71 }
  72
  73 int DLoader_Exec_Cmd(char *cmdbuf)
  74 {
  75         struct ProtoFunctionHook *p;
  76
  77         for (p = ProtoHookList; p; p = p->next) {
  78                 if (!strncasecmp(cmdbuf, p->cmd, 4)) {
  79                         p->handler(&cmdbuf[5]);
  80                         return 1;
  81                 }
  82         }
  83         return 0;
  84 }
  85
  86 void DLoader_Init(char *pathname)
  87 {
  88         void *fcn_handle;
  89         char dl_error[SIZ];
  90         DIR *dir;
  91         int i;
  92         struct dirent *dptr;
  93         char *(*h_init_fcn) (void);
  94         char *dl_info;
  95
  96         char pathbuf[PATH_MAX];
  97
  98         if ((dir = opendir(pathname)) == NULL) {
  99                 perror("opendir");
 100                 exit(1);
 101         }
 102         while ((dptr = readdir(dir)) != NULL) {
 103                 if (strlen(dptr->d_name) < 4)
 104                         continue;
 105 #ifndef __CYGWIN__
 106                 if (strcasecmp(&dptr->d_name[strlen(dptr->d_name)-3], ".so"))
 107 #else
 108                 if (strcasecmp(&dptr->d_name[strlen(dptr->d_name)-4], ".dll"))
 109 #endif
 110                         continue;
 111
 112                 snprintf(pathbuf, PATH_MAX, "%s/%s", pathname, dptr->d_name);
 113                 lprintf(7, "Initializing %s...\n", pathbuf);
 114
 115 #ifdef RTLD_LAZY
 116                 if (!(fcn_handle = dlopen(pathbuf, RTLD_LAZY)))
 117 #else                           /* OpenBSD */
 118                 if (!(fcn_handle = dlopen(pathbuf, DL_LAZY)))
 119 #endif
 120                 {
 121                         safestrncpy(dl_error, dlerror(), sizeof dl_error);
 122                         for (i=0; i<strlen(dl_error); ++i)
 123                                 if (!isprint(dl_error[i]))
 124                                         dl_error[i]='.';
 125                         fprintf(stderr, "DLoader_Init dlopen failed: %s\n",
 126                                 dl_error);
 127                         continue;
 128                 }
 129                 h_init_fcn = (char * (*)(void))
 130 #ifndef __OpenBSD__
 131                     dlsym(fcn_handle, "Dynamic_Module_Init");
 132 #else
 133                     dlsym(fcn_handle, "_Dynamic_Module_Init");
 134 #endif
 135
 136                 if (dlerror() != NULL) {
 137                         fprintf(stderr, "DLoader_Init dlsym failed\n");
 138                         continue;
 139                 }
 140                 dl_info = h_init_fcn();
 141
 142                 lprintf(3, "Loaded module: %s\n", dl_info);
 143         }       /* While */
 144 }
 145
 146
 147
 148 void CtdlRegisterLogHook(void (*fcn_ptr) (char *), int loglevel)
 149 {
 150
 151         struct LogFunctionHook *newfcn;
 152
 153         newfcn = (struct LogFunctionHook *)
 154             mallok(sizeof(struct LogFunctionHook));
 155         newfcn->next = LogHookTable;
 156         newfcn->h_function_pointer = fcn_ptr;
 157         newfcn->loglevel = loglevel;
 158         LogHookTable = newfcn;
 159
 160         lprintf(5, "Registered a new logging function\n");
 161 }
 162
 163
 164 void CtdlRegisterCleanupHook(void (*fcn_ptr) (void))
 165 {
 166
 167         struct CleanupFunctionHook *newfcn;
 168
 169         newfcn = (struct CleanupFunctionHook *)
 170             mallok(sizeof(struct CleanupFunctionHook));
 171         newfcn->next = CleanupHookTable;
 172         newfcn->h_function_pointer = fcn_ptr;
 173         CleanupHookTable = newfcn;
 174
 175         lprintf(5, "Registered a new cleanup function\n");
 176 }
 177
 178
 179 void CtdlRegisterSessionHook(void (*fcn_ptr) (void), int EventType)
 180 {
 181
 182         struct SessionFunctionHook *newfcn;
 183
 184         newfcn = (struct SessionFunctionHook *)
 185             mallok(sizeof(struct SessionFunctionHook));
 186         newfcn->next = SessionHookTable;
 187         newfcn->h_function_pointer = fcn_ptr;
 188         newfcn->eventtype = EventType;
 189         SessionHookTable = newfcn;
 190
 191         lprintf(5, "Registered a new session function (type %d)\n",
 192                 EventType);
 193 }
 194
 195
 196 void CtdlRegisterUserHook(void (*fcn_ptr) (char *, long), int EventType)
 197 {
 198
 199         struct UserFunctionHook *newfcn;
 200
 201         newfcn = (struct UserFunctionHook *)
 202             mallok(sizeof(struct UserFunctionHook));
 203         newfcn->next = UserHookTable;
 204         newfcn->h_function_pointer = fcn_ptr;
 205         newfcn->eventtype = EventType;
 206         UserHookTable = newfcn;
 207
 208         lprintf(5, "Registered a new user function (type %d)\n",
 209                 EventType);
 210 }
 211
 212
 213 void CtdlRegisterMessageHook(int (*handler)(struct CtdlMessage *),
 214                                 int EventType)
 215 {
 216
 217         struct MessageFunctionHook *newfcn;
 218
 219         newfcn = (struct MessageFunctionHook *)
 220             mallok(sizeof(struct MessageFunctionHook));
 221         newfcn->next = MessageHookTable;
 222         newfcn->h_function_pointer = handler;
 223         newfcn->eventtype = EventType;
 224         MessageHookTable = newfcn;
 225
 226         lprintf(5, "Registered a new message function (type %d)\n",
 227                 EventType);
 228 }
 229
 230
 231 void CtdlRegisterXmsgHook(int (*fcn_ptr) (char *, char *, char *), int order)
 232 {
 233
 234         struct XmsgFunctionHook *newfcn;
 235
 236         newfcn = (struct XmsgFunctionHook *)
 237             mallok(sizeof(struct XmsgFunctionHook));
 238         newfcn->next = XmsgHookTable;
 239         newfcn->order = order;
 240         newfcn->h_function_pointer = fcn_ptr;
 241         XmsgHookTable = newfcn;
 242         lprintf(5, "Registered a new x-msg function (priority %d)\n", order);
 243 }
 244
 245 void CtdlRegisterServiceHook(int tcp_port,
 246                         char *sockpath,
 247                         void (*h_greeting_function) (void),
 248                         void (*h_command_function) (void) )
 249 {
 250         struct ServiceFunctionHook *newfcn;
 251         char message[SIZ];
 252
 253         newfcn = (struct ServiceFunctionHook *)
 254             mallok(sizeof(struct ServiceFunctionHook));
 255         newfcn->next = ServiceHookTable;
 256         newfcn->tcp_port = tcp_port;
 257         newfcn->sockpath = sockpath;
 258         newfcn->h_greeting_function = h_greeting_function;
 259         newfcn->h_command_function = h_command_function;
 260
 261         if (sockpath != NULL) {
 262                 newfcn->msock = ig_uds_server(sockpath, config.c_maxsessions);
 263                 sprintf(message, "Unix domain socket '%s': ", sockpath);
 264         }
 265         else if (tcp_port <= 0) {       /* port -1 to disable */
 266                 lprintf(7, "Service has been manually disabled, skipping\n");
 267                 phree(newfcn);
 268                 return;
 269         }
 270         else {
 271                 newfcn->msock = ig_tcp_server(tcp_port, config.c_maxsessions);
 272                 sprintf(message, "TCP port %d: ", tcp_port);
 273         }
 274
 275         if (newfcn->msock > 0) {
 276                 ServiceHookTable = newfcn;
 277                 strcat(message, "registered.");
 278                 lprintf(5, "%s\n", message);
 279         }
 280         else {
 281                 strcat(message, "FAILED.");
 282                 lprintf(2, "%s\n", message);
 283                 phree(newfcn);
 284         }
 285 }
 286
 287
 288
 289 void PerformSessionHooks(int EventType)
 290 {
 291         struct SessionFunctionHook *fcn;
 292
 293         for (fcn = SessionHookTable; fcn != NULL; fcn = fcn->next) {
 294                 if (fcn->eventtype == EventType) {
 295                         (*fcn->h_function_pointer) ();
 296                 }
 297         }
 298 }
 299
 300 void PerformLogHooks(int loglevel, char *logmsg)
 301 {
 302         struct LogFunctionHook *fcn;
 303
 304         for (fcn = LogHookTable; fcn != NULL; fcn = fcn->next) {
 305                 if (fcn->loglevel >= loglevel) {
 306                         (*fcn->h_function_pointer) (logmsg);
 307                 }
 308         }
 309 }
 310
 311 void PerformUserHooks(char *username, long usernum, int EventType)
 312 {
 313         struct UserFunctionHook *fcn;
 314
 315         for (fcn = UserHookTable; fcn != NULL; fcn = fcn->next) {
 316                 if (fcn->eventtype == EventType) {
 317                         (*fcn->h_function_pointer) (username, usernum);
 318                 }
 319         }
 320 }
 321
 322 int PerformMessageHooks(struct CtdlMessage *msg, int EventType)
 323 {
 324         struct MessageFunctionHook *fcn;
 325         int total_retval = 0;
 326
 327         /* Other code may elect to protect this message from server-side
 328          * handlers; if this is the case, don't do anything.
 329         lprintf(9, "** Event type is %d, flags are %d\n",
 330                 EventType, msg->cm_flags);
 331          */
 332         if (msg->cm_flags & CM_SKIP_HOOKS) {
 333                 lprintf(9, "Skipping hooks\n");
 334                 return(0);
 335         }
 336
 337         /* Otherwise, run all the hooks appropriate to this event type.
 338          */
 339         for (fcn = MessageHookTable; fcn != NULL; fcn = fcn->next) {
 340                 if (fcn->eventtype == EventType) {
 341                         total_retval = total_retval +
 342                                 (*fcn->h_function_pointer) (msg);
 343                 }
 344         }
 345
 346         /* Return the sum of the return codes from the hook functions.  If
 347          * this is an EVT_BEFORESAVE event, a nonzero return code will cause
 348          * the save operation to abort.
 349          */
 350         return total_retval;
 351 }
 352
 353
 354
 355 int PerformXmsgHooks(char *sender, char *recp, char *msg)
 356 {
 357         struct XmsgFunctionHook *fcn;
 358         int total_sent = 0;
 359         int p;
 360
 361         for (p=0; p<MAX_XMSG_PRI; ++p) {
 362                 for (fcn = XmsgHookTable; fcn != NULL; fcn = fcn->next) {
 363                         if (fcn->order == p) {
 364                                 total_sent +=
 365                                         (*fcn->h_function_pointer)
 366                                                 (sender, recp, msg);
 367                         }
 368                 }
 369                 /* Break out of the loop if a higher-priority function
 370                  * successfully delivered the message.  This prevents duplicate
 371                  * deliveries to local users simultaneously signed onto
 372                  * remote services.
 373                  */
 374                 if (total_sent) goto DONE;
 375         }
 376 DONE:   return total_sent;
 377 }