+
+
+ /* If ${dlfunc support is configured, handle calling dynamically-loaded
+ functions, unless locked out at this time. Syntax is ${dlfunc{file}{func}}
+ or ${dlfunc{file}{func}{arg}} or ${dlfunc{file}{func}{arg1}{arg2}} or up to
+ a maximum of EXPAND_DLFUNC_MAX_ARGS arguments (defined below). */
+
+ #define EXPAND_DLFUNC_MAX_ARGS 8
+
+ case EITEM_DLFUNC:
+ #ifndef EXPAND_DLFUNC
+ expand_string_message = US"\"${dlfunc\" encountered, but this facility "
+ "is not included in this binary";
+ goto EXPAND_FAILED;
+
+ #else /* EXPAND_DLFUNC */
+ {
+ tree_node *t;
+ exim_dlfunc_t *func;
+ uschar *result;
+ int status, argc;
+ uschar *argv[EXPAND_DLFUNC_MAX_ARGS + 3];
+
+ if ((expand_forbid & RDO_DLFUNC) != 0)
+ {
+ expand_string_message =
+ US"dynamically-loaded functions are not permitted";
+ goto EXPAND_FAILED;
+ }
+
+ switch(read_subs(argv, EXPAND_DLFUNC_MAX_ARGS + 2, 2, &s, skipping,
+ TRUE, US"dlfunc"))
+ {
+ case 1: goto EXPAND_FAILED_CURLY;
+ case 2:
+ case 3: goto EXPAND_FAILED;
+ }
+
+ /* If skipping, we don't actually do anything */
+
+ if (skipping) continue;
+
+ /* Look up the dynamically loaded object handle in the tree. If it isn't
+ found, dlopen() the file and put the handle in the tree for next time. */
+
+ t = tree_search(dlobj_anchor, argv[0]);
+ if (t == NULL)
+ {
+ void *handle = dlopen(CS argv[0], RTLD_LAZY);
+ if (handle == NULL)
+ {
+ expand_string_message = string_sprintf("dlopen \"%s\" failed: %s",
+ argv[0], dlerror());
+ log_write(0, LOG_MAIN|LOG_PANIC, "%s", expand_string_message);
+ goto EXPAND_FAILED;
+ }
+ t = store_get_perm(sizeof(tree_node) + Ustrlen(argv[0]));
+ Ustrcpy(t->name, argv[0]);
+ t->data.ptr = handle;
+ (void)tree_insertnode(&dlobj_anchor, t);
+ }
+
+ /* Having obtained the dynamically loaded object handle, look up the
+ function pointer. */
+
+ func = (exim_dlfunc_t *)dlsym(t->data.ptr, CS argv[1]);
+ if (func == NULL)
+ {
+ expand_string_message = string_sprintf("dlsym \"%s\" in \"%s\" failed: "
+ "%s", argv[1], argv[0], dlerror());
+ log_write(0, LOG_MAIN|LOG_PANIC, "%s", expand_string_message);
+ goto EXPAND_FAILED;
+ }
+
+ /* Call the function and work out what to do with the result. If it
+ returns OK, we have a replacement string; if it returns DEFER then
+ expansion has failed in a non-forced manner; if it returns FAIL then
+ failure was forced; if it returns ERROR or any other value there's a
+ problem, so panic slightly. */
+
+ result = NULL;
+ for (argc = 0; argv[argc] != NULL; argc++);
+ status = func(&result, argc - 2, &argv[2]);
+ if(status == OK)
+ {
+ if (result == NULL) result = US"";
+ yield = string_cat(yield, &size, &ptr, result, Ustrlen(result));
+ continue;
+ }
+ else
+ {
+ expand_string_message = result == NULL ? US"(no message)" : result;
+ if(status == FAIL_FORCED) expand_string_forcedfail = TRUE;
+ else if(status != FAIL)
+ log_write(0, LOG_MAIN|LOG_PANIC, "dlfunc{%s}{%s} failed (%d): %s",
+ argv[0], argv[1], status, expand_string_message);
+ goto EXPAND_FAILED;
+ }
+ }
+ #endif /* EXPAND_DLFUNC */
git://git.exim.org / exim.git / commitdiff