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 #include <unistd.h>
  17 #ifdef HAVE_DLFCN_H
  18 #include <dlfcn.h>
  19 #endif
  20 #ifdef HAVE_DL_H
  21 #include <dl.h>
  22 #include "hpsux.h"
  23 #endif
  24 #include <sys/types.h>
  25 #include <dirent.h>
  26 #include <string.h>
  27 #include <syslog.h>
  28 #include <limits.h>
  29 #include <ctype.h>
  30 #include "citadel.h"
  31 #include "server.h"
  32 #include "dynloader.h"
  33 #include "sysdep_decls.h"
  34 #include "msgbase.h"
  35 #include "tools.h"
  36 #include "config.h"
  37
  38 #ifndef HAVE_SNPRINTF
  39 #include <stdarg.h>
  40 #include "snprintf.h"
  41 #endif
  42
  43 struct LogFunctionHook *LogHookTable = NULL;
  44 struct CleanupFunctionHook *CleanupHookTable = NULL;
  45 struct SessionFunctionHook *SessionHookTable = NULL;
  46 struct UserFunctionHook *UserHookTable = NULL;
  47 struct XmsgFunctionHook *XmsgHookTable = NULL;
  48 struct MessageFunctionHook *MessageHookTable = NULL;
  49 struct NetprocFunctionHook *NetprocHookTable = NULL;
  50 struct ServiceFunctionHook *ServiceHookTable = NULL;
  51
  52 struct ProtoFunctionHook {
  53         void (*handler) (char *cmdbuf);
  54         char *cmd;
  55         char *desc;
  56         struct ProtoFunctionHook *next;
  57 } *ProtoHookList = NULL;
  58
  59 void CtdlRegisterProtoHook(void (*handler) (char *), char *cmd, char *desc)
  60 {
  61         struct ProtoFunctionHook *p;
  62
  63         p = (struct ProtoFunctionHook *)
  64                 mallok(sizeof(struct ProtoFunctionHook));
  65
  66         if (p == NULL) {
  67                 fprintf(stderr, "can't malloc new ProtoFunctionHook\n");
  68                 exit(EXIT_FAILURE);
  69         }
  70         p->handler = handler;
  71         p->cmd = cmd;
  72         p->desc = desc;
  73         p->next = ProtoHookList;
  74         ProtoHookList = p;
  75         lprintf(5, "Registered server command %s (%s)\n", cmd, desc);
  76 }
  77
  78
  79 void CtdlUnregisterProtoHook(void (*handler) (char *), char *cmd)
  80 {
  81         struct ProtoFunctionHook *cur, *p;
  82
  83         for (cur = ProtoHookList; cur != NULL; cur = cur->next) {
  84                 /* This will also remove duplicates if any */
  85                 while (cur != NULL &&
  86                                 handler == cur->handler &&
  87                                 !strcmp(cmd, cur->cmd)) {
  88                         lprintf(5, "Unregistered server command %s (%s)\n",
  89                                         cmd, cur->desc);
  90                         p = cur->next;
  91                         if (cur == ProtoHookList) {
  92                                 ProtoHookList = p;
  93                         }
  94                         phree(cur);
  95                         cur = p;
  96                 }
  97         }
  98 }
  99
 100
 101 int DLoader_Exec_Cmd(char *cmdbuf)
 102 {
 103         struct ProtoFunctionHook *p;
 104
 105         for (p = ProtoHookList; p; p = p->next) {
 106                 if (!strncasecmp(cmdbuf, p->cmd, 4)) {
 107                         p->handler(&cmdbuf[5]);
 108                         return 1;
 109                 }
 110         }
 111         return 0;
 112 }
 113
 114 void DLoader_Init(char *pathname)
 115 {
 116         void *fcn_handle;
 117         char dl_error[SIZ];
 118         DIR *dir;
 119         int i;
 120         struct dirent *dptr;
 121         char *(*h_init_fcn) (void);
 122         char *dl_info;
 123
 124         char pathbuf[PATH_MAX];
 125
 126         if ((dir = opendir(pathname)) == NULL) {
 127                 perror("opendir");
 128                 exit(1);
 129         }
 130         while ((dptr = readdir(dir)) != NULL) {
 131                 if (strlen(dptr->d_name) < 4)
 132                         continue;
 133 #ifndef __CYGWIN__
 134                 if (strcasecmp(&dptr->d_name[strlen(dptr->d_name)-3], ".so"))
 135 #else
 136                 if (strcasecmp(&dptr->d_name[strlen(dptr->d_name)-4], ".dll"))
 137 #endif
 138                         continue;
 139
 140                 snprintf(pathbuf, PATH_MAX, "%s/%s", pathname, dptr->d_name);
 141                 lprintf(7, "Initializing %s...\n", pathbuf);
 142
 143 #ifdef RTLD_LAZY
 144                 if (!(fcn_handle = dlopen(pathbuf, RTLD_LAZY)))
 145 #else                           /* OpenBSD */
 146                 if (!(fcn_handle = dlopen(pathbuf, DL_LAZY)))
 147 #endif
 148                 {
 149                         safestrncpy(dl_error, dlerror(), sizeof dl_error);
 150                         for (i=0; i<strlen(dl_error); ++i)
 151                                 if (!isprint(dl_error[i]))
 152                                         dl_error[i]='.';
 153                         fprintf(stderr, "DLoader_Init dlopen failed: %s\n",
 154                                 dl_error);
 155                         continue;
 156                 }
 157                 h_init_fcn = (char * (*)(void))
 158 #ifndef __OpenBSD__
 159                     dlsym(fcn_handle, "Dynamic_Module_Init");
 160 #else
 161                     dlsym(fcn_handle, "_Dynamic_Module_Init");
 162 #endif
 163
 164                 if (dlerror() != NULL) {
 165                         fprintf(stderr, "DLoader_Init dlsym failed\n");
 166                         continue;
 167                 }
 168                 dl_info = h_init_fcn();
 169
 170                 lprintf(3, "Loaded module: %s\n", dl_info);
 171         }       /* While */
 172 }
 173
 174
 175
 176 void CtdlRegisterLogHook(void (*fcn_ptr) (char *), int loglevel)
 177 {
 178
 179         struct LogFunctionHook *newfcn;
 180
 181         newfcn = (struct LogFunctionHook *)
 182             mallok(sizeof(struct LogFunctionHook));
 183         newfcn->next = LogHookTable;
 184         newfcn->h_function_pointer = fcn_ptr;
 185         newfcn->loglevel = loglevel;
 186         LogHookTable = newfcn;
 187
 188         lprintf(5, "Registered a new logging function\n");
 189 }
 190
 191
 192 void CtdlUnregisterLogHook(void (*fcn_ptr) (char *), int loglevel)
 193 {
 194         struct LogFunctionHook *cur, *p;
 195
 196         for (cur = LogHookTable; cur != NULL; cur = cur->next) {
 197                 /* This will also remove duplicates if any */
 198                 while (cur != NULL &&
 199                                 fcn_ptr == cur->h_function_pointer &&
 200                                 loglevel == cur->loglevel) {
 201                         lprintf(5, "Unregistered logging function\n");
 202                         p = cur->next;
 203                         if (cur == LogHookTable) {
 204                                 LogHookTable = p;
 205                         }
 206                         phree(cur);
 207                         cur = p;
 208                 }
 209         }
 210 }
 211
 212
 213 void CtdlRegisterCleanupHook(void (*fcn_ptr) (void))
 214 {
 215
 216         struct CleanupFunctionHook *newfcn;
 217
 218         newfcn = (struct CleanupFunctionHook *)
 219             mallok(sizeof(struct CleanupFunctionHook));
 220         newfcn->next = CleanupHookTable;
 221         newfcn->h_function_pointer = fcn_ptr;
 222         CleanupHookTable = newfcn;
 223
 224         lprintf(5, "Registered a new cleanup function\n");
 225 }
 226
 227
 228 void CtdlUnregisterCleanupHook(void (*fcn_ptr) (void))
 229 {
 230         struct CleanupFunctionHook *cur, *p;
 231
 232         for (cur = CleanupHookTable; cur != NULL; cur = cur->next) {
 233                 /* This will also remove duplicates if any */
 234                 while (cur != NULL &&
 235                                 fcn_ptr == cur->h_function_pointer) {
 236                         lprintf(5, "Unregistered cleanup function\n");
 237                         p = cur->next;
 238                         if (cur == CleanupHookTable) {
 239                                 CleanupHookTable = p;
 240                         }
 241                         phree(cur);
 242                         cur = p;
 243                 }
 244         }
 245 }
 246
 247
 248 void CtdlRegisterSessionHook(void (*fcn_ptr) (void), int EventType)
 249 {
 250
 251         struct SessionFunctionHook *newfcn;
 252
 253         newfcn = (struct SessionFunctionHook *)
 254             mallok(sizeof(struct SessionFunctionHook));
 255         newfcn->next = SessionHookTable;
 256         newfcn->h_function_pointer = fcn_ptr;
 257         newfcn->eventtype = EventType;
 258         SessionHookTable = newfcn;
 259
 260         lprintf(5, "Registered a new session function (type %d)\n",
 261                 EventType);
 262 }
 263
 264
 265 void CtdlUnregisterSessionHook(void (*fcn_ptr) (void), int EventType)
 266 {
 267         struct SessionFunctionHook *cur, *p;
 268
 269         for (cur = SessionHookTable; cur != NULL; cur = cur->next) {
 270                 /* This will also remove duplicates if any */
 271                 while (cur != NULL &&
 272                                 fcn_ptr == cur->h_function_pointer &&
 273                                 EventType == cur->eventtype) {
 274                         lprintf(5, "Unregistered session function (type %d)\n",
 275                                         EventType);
 276                         p = cur->next;
 277                         if (cur == SessionHookTable) {
 278                                 SessionHookTable = p;
 279                         }
 280                         phree(cur);
 281                         cur = p;
 282                 }
 283         }
 284 }
 285
 286
 287 void CtdlRegisterUserHook(void (*fcn_ptr) (char *, long), int EventType)
 288 {
 289
 290         struct UserFunctionHook *newfcn;
 291
 292         newfcn = (struct UserFunctionHook *)
 293             mallok(sizeof(struct UserFunctionHook));
 294         newfcn->next = UserHookTable;
 295         newfcn->h_function_pointer = fcn_ptr;
 296         newfcn->eventtype = EventType;
 297         UserHookTable = newfcn;
 298
 299         lprintf(5, "Registered a new user function (type %d)\n",
 300                 EventType);
 301 }
 302
 303
 304 void CtdlUnregisterUserHook(void (*fcn_ptr) (char *, long), int EventType)
 305 {
 306         struct UserFunctionHook *cur, *p;
 307
 308         for (cur = UserHookTable; cur != NULL; cur = cur->next) {
 309                 /* This will also remove duplicates if any */
 310                 while (cur != NULL &&
 311                                 fcn_ptr == cur->h_function_pointer &&
 312                                 EventType == cur->eventtype) {
 313                         lprintf(5, "Unregistered user function (type %d)\n",
 314                                         EventType);
 315                         p = cur->next;
 316                         if (cur == UserHookTable) {
 317                                 UserHookTable = p;
 318                         }
 319                         phree(cur);
 320                         cur = p;
 321                 }
 322         }
 323 }
 324
 325
 326 void CtdlRegisterMessageHook(int (*handler)(struct CtdlMessage *),
 327                                 int EventType)
 328 {
 329
 330         struct MessageFunctionHook *newfcn;
 331
 332         newfcn = (struct MessageFunctionHook *)
 333             mallok(sizeof(struct MessageFunctionHook));
 334         newfcn->next = MessageHookTable;
 335         newfcn->h_function_pointer = handler;
 336         newfcn->eventtype = EventType;
 337         MessageHookTable = newfcn;
 338
 339         lprintf(5, "Registered a new message function (type %d)\n",
 340                 EventType);
 341 }
 342
 343
 344 void CtdlUnregisterMessageHook(int (*handler)(struct CtdlMessage *),
 345                 int EventType)
 346 {
 347         struct MessageFunctionHook *cur, *p;
 348
 349         for (cur = MessageHookTable; cur != NULL; cur = cur->next) {
 350                 /* This will also remove duplicates if any */
 351                 while (cur != NULL &&
 352                                 handler == cur->h_function_pointer &&
 353                                 EventType == cur->eventtype) {
 354                         lprintf(5, "Unregistered message function (type %d)\n",
 355                                         EventType);
 356                         p = cur->next;
 357                         if (cur == MessageHookTable) {
 358                                 MessageHookTable = p;
 359                         }
 360                         phree(cur);
 361                         cur = p;
 362                 }
 363         }
 364 }
 365
 366
 367 void CtdlRegisterNetprocHook(int (*handler)(struct CtdlMessage *, char *) )
 368 {
 369         struct NetprocFunctionHook *newfcn;
 370
 371         newfcn = (struct NetprocFunctionHook *)
 372             mallok(sizeof(struct NetprocFunctionHook));
 373         newfcn->next = NetprocHookTable;
 374         newfcn->h_function_pointer = handler;
 375         NetprocHookTable = newfcn;
 376
 377         lprintf(5, "Registered a new netproc function\n");
 378 }
 379
 380
 381 void CtdlUnregisterNetprocHook(int (*handler)(struct CtdlMessage *, char *) )
 382 {
 383         struct NetprocFunctionHook *cur, *p;
 384
 385         for (cur = NetprocHookTable; cur != NULL; cur = cur->next) {
 386                 /* This will also remove duplicates if any */
 387                 while (cur != NULL &&
 388                                 handler == cur->h_function_pointer ) {
 389                         lprintf(5, "Unregistered netproc function\n");
 390                         p = cur->next;
 391                         if (cur == NetprocHookTable) {
 392                                 NetprocHookTable = p;
 393                         }
 394                         phree(cur);
 395                         cur = p;
 396                 }
 397         }
 398 }
 399
 400
 401 void CtdlRegisterXmsgHook(int (*fcn_ptr) (char *, char *, char *), int order)
 402 {
 403
 404         struct XmsgFunctionHook *newfcn;
 405
 406         newfcn = (struct XmsgFunctionHook *)
 407             mallok(sizeof(struct XmsgFunctionHook));
 408         newfcn->next = XmsgHookTable;
 409         newfcn->order = order;
 410         newfcn->h_function_pointer = fcn_ptr;
 411         XmsgHookTable = newfcn;
 412         lprintf(5, "Registered a new x-msg function (priority %d)\n", order);
 413 }
 414
 415
 416 void CtdlUnregisterXmsgHook(int (*fcn_ptr) (char *, char *, char *), int order)
 417 {
 418         struct XmsgFunctionHook *cur, *p;
 419
 420         for (cur = XmsgHookTable; cur != NULL; cur = cur->next) {
 421                 /* This will also remove duplicates if any */
 422                 while (cur != NULL &&
 423                                 fcn_ptr == cur->h_function_pointer &&
 424                                 order == cur->order) {
 425                         lprintf(5, "Unregistered x-msg function "
 426                                         "(priority %d)\n", order);
 427                         p = cur->next;
 428                         if (cur == XmsgHookTable) {
 429                                 XmsgHookTable = p;
 430                         }
 431                         phree(cur);
 432                         cur = p;
 433                 }
 434         }
 435 }
 436
 437
 438 void CtdlRegisterServiceHook(int tcp_port,
 439                         char *sockpath,
 440                         void (*h_greeting_function) (void),
 441                         void (*h_command_function) (void) )
 442 {
 443         struct ServiceFunctionHook *newfcn;
 444         char message[SIZ];
 445
 446         newfcn = (struct ServiceFunctionHook *)
 447             mallok(sizeof(struct ServiceFunctionHook));
 448         newfcn->next = ServiceHookTable;
 449         newfcn->tcp_port = tcp_port;
 450         newfcn->sockpath = sockpath;
 451         newfcn->h_greeting_function = h_greeting_function;
 452         newfcn->h_command_function = h_command_function;
 453
 454         if (sockpath != NULL) {
 455                 newfcn->msock = ig_uds_server(sockpath, config.c_maxsessions);
 456                 sprintf(message, "Unix domain socket '%s': ", sockpath);
 457         }
 458         else if (tcp_port <= 0) {       /* port -1 to disable */
 459                 lprintf(7, "Service has been manually disabled, skipping\n");
 460                 phree(newfcn);
 461                 return;
 462         }
 463         else {
 464                 newfcn->msock = ig_tcp_server(tcp_port, config.c_maxsessions);
 465                 sprintf(message, "TCP port %d: ", tcp_port);
 466         }
 467
 468         if (newfcn->msock > 0) {
 469                 ServiceHookTable = newfcn;
 470                 strcat(message, "registered.");
 471                 lprintf(5, "%s\n", message);
 472         }
 473         else {
 474                 strcat(message, "FAILED.");
 475                 lprintf(2, "%s\n", message);
 476                 phree(newfcn);
 477         }
 478 }
 479
 480
 481 void CtdlUnregisterServiceHook(int tcp_port, char *sockpath,
 482                         void (*h_greeting_function) (void),
 483                         void (*h_command_function) (void) )
 484 {
 485         struct ServiceFunctionHook *cur, *p;
 486
 487         for (cur = ServiceHookTable; cur != NULL; cur = cur->next) {
 488                 /* This will also remove duplicates if any */
 489                 while (cur != NULL &&
 490                                 !(sockpath && cur->sockpath &&
 491                                         strcmp(sockpath, cur->sockpath)) &&
 492                                 h_greeting_function == cur->h_greeting_function &&
 493                                 h_command_function == cur->h_command_function &&
 494                                 tcp_port == cur->tcp_port) {
 495                         close(cur->msock);
 496                         if (sockpath) {
 497                                 lprintf(5, "Closed UNIX domain socket %s\n",
 498                                                 sockpath);
 499                         } else if (tcp_port) {
 500                                 lprintf(5, "Closed TCP port %d\n", tcp_port);
 501                         } else {
 502                                 lprintf(5, "Unregistered unknown service\n");
 503                         }
 504                         p = cur->next;
 505                         if (cur == ServiceHookTable) {
 506                                 ServiceHookTable = p;
 507                         }
 508                         phree(cur);
 509                         cur = p;
 510                 }
 511         }
 512 }
 513
 514
 515 void PerformSessionHooks(int EventType)
 516 {
 517         struct SessionFunctionHook *fcn;
 518
 519         for (fcn = SessionHookTable; fcn != NULL; fcn = fcn->next) {
 520                 if (fcn->eventtype == EventType) {
 521                         (*fcn->h_function_pointer) ();
 522                 }
 523         }
 524 }
 525
 526 void PerformLogHooks(int loglevel, char *logmsg)
 527 {
 528         struct LogFunctionHook *fcn;
 529
 530         for (fcn = LogHookTable; fcn != NULL; fcn = fcn->next) {
 531                 if (fcn->loglevel >= loglevel) {
 532                         (*fcn->h_function_pointer) (logmsg);
 533                 }
 534         }
 535 }
 536
 537 void PerformUserHooks(char *username, long usernum, int EventType)
 538 {
 539         struct UserFunctionHook *fcn;
 540
 541         for (fcn = UserHookTable; fcn != NULL; fcn = fcn->next) {
 542                 if (fcn->eventtype == EventType) {
 543                         (*fcn->h_function_pointer) (username, usernum);
 544                 }
 545         }
 546 }
 547
 548 int PerformMessageHooks(struct CtdlMessage *msg, int EventType)
 549 {
 550         struct MessageFunctionHook *fcn;
 551         int total_retval = 0;
 552
 553         /* Other code may elect to protect this message from server-side
 554          * handlers; if this is the case, don't do anything.
 555         lprintf(9, "** Event type is %d, flags are %d\n",
 556                 EventType, msg->cm_flags);
 557          */
 558         if (msg->cm_flags & CM_SKIP_HOOKS) {
 559                 lprintf(9, "Skipping hooks\n");
 560                 return(0);
 561         }
 562
 563         /* Otherwise, run all the hooks appropriate to this event type.
 564          */
 565         for (fcn = MessageHookTable; fcn != NULL; fcn = fcn->next) {
 566                 if (fcn->eventtype == EventType) {
 567                         total_retval = total_retval +
 568                                 (*fcn->h_function_pointer) (msg);
 569                 }
 570         }
 571
 572         /* Return the sum of the return codes from the hook functions.  If
 573          * this is an EVT_BEFORESAVE event, a nonzero return code will cause
 574          * the save operation to abort.
 575          */
 576         return total_retval;
 577 }
 578
 579
 580
 581 int PerformNetprocHooks(struct CtdlMessage *msg, char *target_room)
 582 {
 583         struct NetprocFunctionHook *fcn;
 584         int total_retval = 0;
 585
 586         for (fcn = NetprocHookTable; fcn != NULL; fcn = fcn->next) {
 587                 total_retval = total_retval +
 588                         (*fcn->h_function_pointer) (msg, target_room);
 589         }
 590
 591         /* Return the sum of the return codes from the hook functions.
 592          * A nonzero return code will cause the message to *not* be imported.
 593          */
 594         return total_retval;
 595 }
 596
 597
 598
 599 int PerformXmsgHooks(char *sender, char *recp, char *msg)
 600 {
 601         struct XmsgFunctionHook *fcn;
 602         int total_sent = 0;
 603         int p;
 604
 605         for (p=0; p<MAX_XMSG_PRI; ++p) {
 606                 for (fcn = XmsgHookTable; fcn != NULL; fcn = fcn->next) {
 607                         if (fcn->order == p) {
 608                                 total_sent +=
 609                                         (*fcn->h_function_pointer)
 610                                                 (sender, recp, msg);
 611                         }
 612                 }
 613                 /* Break out of the loop if a higher-priority function
 614                  * successfully delivered the message.  This prevents duplicate
 615                  * deliveries to local users simultaneously signed onto
 616                  * remote services.
 617                  */
 618                 if (total_sent) break;
 619         }
 620         return total_sent;
 621 }