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;
  60
  61         p = (struct ProtoFunctionHook *)
  62                 mallok(sizeof(struct ProtoFunctionHook));
  63
  64         if (p == NULL) {
  65                 fprintf(stderr, "can't malloc new ProtoFunctionHook\n");
  66                 exit(EXIT_FAILURE);
  67         }
  68         p->handler = handler;
  69         p->cmd = cmd;
  70         p->desc = desc;
  71         p->next = ProtoHookList;
  72         ProtoHookList = p;
  73         lprintf(5, "Registered server command %s (%s)\n", cmd, desc);
  74 }
  75
  76 int DLoader_Exec_Cmd(char *cmdbuf)
  77 {
  78         struct ProtoFunctionHook *p;
  79
  80         for (p = ProtoHookList; p; p = p->next) {
  81                 if (!strncasecmp(cmdbuf, p->cmd, 4)) {
  82                         p->handler(&cmdbuf[5]);
  83                         return 1;
  84                 }
  85         }
  86         return 0;
  87 }
  88
  89 void DLoader_Init(char *pathname)
  90 {
  91         void *fcn_handle;
  92         char dl_error[SIZ];
  93         DIR *dir;
  94         int i;
  95         struct dirent *dptr;
  96         char *(*h_init_fcn) (void);
  97         char *dl_info;
  98
  99         char pathbuf[PATH_MAX];
 100
 101         if ((dir = opendir(pathname)) == NULL) {
 102                 perror("opendir");
 103                 exit(1);
 104         }
 105         while ((dptr = readdir(dir)) != NULL) {
 106                 if (strlen(dptr->d_name) < 4)
 107                         continue;
 108 #ifndef __CYGWIN__
 109                 if (strcasecmp(&dptr->d_name[strlen(dptr->d_name)-3], ".so"))
 110 #else
 111                 if (strcasecmp(&dptr->d_name[strlen(dptr->d_name)-4], ".dll"))
 112 #endif
 113                         continue;
 114
 115                 snprintf(pathbuf, PATH_MAX, "%s/%s", pathname, dptr->d_name);
 116                 lprintf(7, "Initializing %s...\n", pathbuf);
 117
 118 #ifdef RTLD_LAZY
 119                 if (!(fcn_handle = dlopen(pathbuf, RTLD_LAZY)))
 120 #else                           /* OpenBSD */
 121                 if (!(fcn_handle = dlopen(pathbuf, DL_LAZY)))
 122 #endif
 123                 {
 124                         safestrncpy(dl_error, dlerror(), sizeof dl_error);
 125                         for (i=0; i<strlen(dl_error); ++i)
 126                                 if (!isprint(dl_error[i]))
 127                                         dl_error[i]='.';
 128                         fprintf(stderr, "DLoader_Init dlopen failed: %s\n",
 129                                 dl_error);
 130                         continue;
 131                 }
 132                 h_init_fcn = (char * (*)(void))
 133 #ifndef __OpenBSD__
 134                     dlsym(fcn_handle, "Dynamic_Module_Init");
 135 #else
 136                     dlsym(fcn_handle, "_Dynamic_Module_Init");
 137 #endif
 138
 139                 if (dlerror() != NULL) {
 140                         fprintf(stderr, "DLoader_Init dlsym failed\n");
 141                         continue;
 142                 }
 143                 dl_info = h_init_fcn();
 144
 145                 lprintf(3, "Loaded module: %s\n", dl_info);
 146         }       /* While */
 147 }
 148
 149
 150
 151 void CtdlRegisterLogHook(void (*fcn_ptr) (char *), int loglevel)
 152 {
 153
 154         struct LogFunctionHook *newfcn;
 155
 156         newfcn = (struct LogFunctionHook *)
 157             mallok(sizeof(struct LogFunctionHook));
 158         newfcn->next = LogHookTable;
 159         newfcn->h_function_pointer = fcn_ptr;
 160         newfcn->loglevel = loglevel;
 161         LogHookTable = newfcn;
 162
 163         lprintf(5, "Registered a new logging function\n");
 164 }
 165
 166
 167 void CtdlRegisterCleanupHook(void (*fcn_ptr) (void))
 168 {
 169
 170         struct CleanupFunctionHook *newfcn;
 171
 172         newfcn = (struct CleanupFunctionHook *)
 173             mallok(sizeof(struct CleanupFunctionHook));
 174         newfcn->next = CleanupHookTable;
 175         newfcn->h_function_pointer = fcn_ptr;
 176         CleanupHookTable = newfcn;
 177
 178         lprintf(5, "Registered a new cleanup function\n");
 179 }
 180
 181
 182 void CtdlRegisterSessionHook(void (*fcn_ptr) (void), int EventType)
 183 {
 184
 185         struct SessionFunctionHook *newfcn;
 186
 187         newfcn = (struct SessionFunctionHook *)
 188             mallok(sizeof(struct SessionFunctionHook));
 189         newfcn->next = SessionHookTable;
 190         newfcn->h_function_pointer = fcn_ptr;
 191         newfcn->eventtype = EventType;
 192         SessionHookTable = newfcn;
 193
 194         lprintf(5, "Registered a new session function (type %d)\n",
 195                 EventType);
 196 }
 197
 198
 199 void CtdlRegisterUserHook(void (*fcn_ptr) (char *, long), int EventType)
 200 {
 201
 202         struct UserFunctionHook *newfcn;
 203
 204         newfcn = (struct UserFunctionHook *)
 205             mallok(sizeof(struct UserFunctionHook));
 206         newfcn->next = UserHookTable;
 207         newfcn->h_function_pointer = fcn_ptr;
 208         newfcn->eventtype = EventType;
 209         UserHookTable = newfcn;
 210
 211         lprintf(5, "Registered a new user function (type %d)\n",
 212                 EventType);
 213 }
 214
 215
 216 void CtdlRegisterMessageHook(int (*handler)(struct CtdlMessage *),
 217                                 int EventType)
 218 {
 219
 220         struct MessageFunctionHook *newfcn;
 221
 222         newfcn = (struct MessageFunctionHook *)
 223             mallok(sizeof(struct MessageFunctionHook));
 224         newfcn->next = MessageHookTable;
 225         newfcn->h_function_pointer = handler;
 226         newfcn->eventtype = EventType;
 227         MessageHookTable = newfcn;
 228
 229         lprintf(5, "Registered a new message function (type %d)\n",
 230                 EventType);
 231 }
 232
 233
 234 void CtdlRegisterXmsgHook(int (*fcn_ptr) (char *, char *, char *), int order)
 235 {
 236
 237         struct XmsgFunctionHook *newfcn;
 238
 239         newfcn = (struct XmsgFunctionHook *)
 240             mallok(sizeof(struct XmsgFunctionHook));
 241         newfcn->next = XmsgHookTable;
 242         newfcn->order = order;
 243         newfcn->h_function_pointer = fcn_ptr;
 244         XmsgHookTable = newfcn;
 245         lprintf(5, "Registered a new x-msg function (priority %d)\n", order);
 246 }
 247
 248 void CtdlRegisterServiceHook(int tcp_port,
 249                         char *sockpath,
 250                         void (*h_greeting_function) (void),
 251                         void (*h_command_function) (void) )
 252 {
 253         struct ServiceFunctionHook *newfcn;
 254         char message[SIZ];
 255
 256         newfcn = (struct ServiceFunctionHook *)
 257             mallok(sizeof(struct ServiceFunctionHook));
 258         newfcn->next = ServiceHookTable;
 259         newfcn->tcp_port = tcp_port;
 260         newfcn->sockpath = sockpath;
 261         newfcn->h_greeting_function = h_greeting_function;
 262         newfcn->h_command_function = h_command_function;
 263
 264         if (sockpath != NULL) {
 265                 newfcn->msock = ig_uds_server(sockpath, config.c_maxsessions);
 266                 sprintf(message, "Unix domain socket '%s': ", sockpath);
 267         }
 268         else if (tcp_port <= 0) {       /* port -1 to disable */
 269                 lprintf(7, "Service has been manually disabled, skipping\n");
 270                 phree(newfcn);
 271                 return;
 272         }
 273         else {
 274                 newfcn->msock = ig_tcp_server(tcp_port, config.c_maxsessions);
 275                 sprintf(message, "TCP port %d: ", tcp_port);
 276         }
 277
 278         if (newfcn->msock > 0) {
 279                 ServiceHookTable = newfcn;
 280                 strcat(message, "registered.");
 281                 lprintf(5, "%s\n", message);
 282         }
 283         else {
 284                 strcat(message, "FAILED.");
 285                 lprintf(2, "%s\n", message);
 286                 phree(newfcn);
 287         }
 288 }
 289
 290
 291
 292 void PerformSessionHooks(int EventType)
 293 {
 294         struct SessionFunctionHook *fcn;
 295
 296         for (fcn = SessionHookTable; fcn != NULL; fcn = fcn->next) {
 297                 if (fcn->eventtype == EventType) {
 298                         (*fcn->h_function_pointer) ();
 299                 }
 300         }
 301 }
 302
 303 void PerformLogHooks(int loglevel, char *logmsg)
 304 {
 305         struct LogFunctionHook *fcn;
 306
 307         for (fcn = LogHookTable; fcn != NULL; fcn = fcn->next) {
 308                 if (fcn->loglevel >= loglevel) {
 309                         (*fcn->h_function_pointer) (logmsg);
 310                 }
 311         }
 312 }
 313
 314 void PerformUserHooks(char *username, long usernum, int EventType)
 315 {
 316         struct UserFunctionHook *fcn;
 317
 318         for (fcn = UserHookTable; fcn != NULL; fcn = fcn->next) {
 319                 if (fcn->eventtype == EventType) {
 320                         (*fcn->h_function_pointer) (username, usernum);
 321                 }
 322         }
 323 }
 324
 325 int PerformMessageHooks(struct CtdlMessage *msg, int EventType)
 326 {
 327         struct MessageFunctionHook *fcn;
 328         int total_retval = 0;
 329
 330         /* Other code may elect to protect this message from server-side
 331          * handlers; if this is the case, don't do anything.
 332         lprintf(9, "** Event type is %d, flags are %d\n",
 333                 EventType, msg->cm_flags);
 334          */
 335         if (msg->cm_flags & CM_SKIP_HOOKS) {
 336                 lprintf(9, "Skipping hooks\n");
 337                 return(0);
 338         }
 339
 340         /* Otherwise, run all the hooks appropriate to this event type.
 341          */
 342         for (fcn = MessageHookTable; fcn != NULL; fcn = fcn->next) {
 343                 if (fcn->eventtype == EventType) {
 344                         total_retval = total_retval +
 345                                 (*fcn->h_function_pointer) (msg);
 346                 }
 347         }
 348
 349         /* Return the sum of the return codes from the hook functions.  If
 350          * this is an EVT_BEFORESAVE event, a nonzero return code will cause
 351          * the save operation to abort.
 352          */
 353         return total_retval;
 354 }
 355
 356
 357
 358 int PerformXmsgHooks(char *sender, char *recp, char *msg)
 359 {
 360         struct XmsgFunctionHook *fcn;
 361         int total_sent = 0;
 362         int p;
 363
 364         for (p=0; p<MAX_XMSG_PRI; ++p) {
 365                 for (fcn = XmsgHookTable; fcn != NULL; fcn = fcn->next) {
 366                         if (fcn->order == p) {
 367                                 total_sent +=
 368                                         (*fcn->h_function_pointer)
 369                                                 (sender, recp, msg);
 370                         }
 371                 }
 372                 /* Break out of the loop if a higher-priority function
 373                  * successfully delivered the message.  This prevents duplicate
 374                  * deliveries to local users simultaneously signed onto
 375                  * remote services.
 376                  */
 377                 if (total_sent) goto DONE;
 378         }
 379 DONE:   return total_sent;
 380 }