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-rw-r--r--src/routers/queryprogram.c538
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diff --git a/src/routers/queryprogram.c b/src/routers/queryprogram.c
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--- /dev/null
+++ b/src/routers/queryprogram.c
@@ -0,0 +1,538 @@
+/*************************************************
+* Exim - an Internet mail transport agent *
+*************************************************/
+
+/* Copyright (c) The Exim Maintainers 2020 - 2022 */
+/* Copyright (c) University of Cambridge 1995 - 2018 */
+/* See the file NOTICE for conditions of use and distribution. */
+
+#include "../exim.h"
+#include "rf_functions.h"
+#include "queryprogram.h"
+
+
+
+/* Options specific to the queryprogram router. */
+
+optionlist queryprogram_router_options[] = {
+ { "*expand_command_group", opt_bool | opt_hidden,
+ OPT_OFF(queryprogram_router_options_block, expand_cmd_gid) },
+ { "*expand_command_user", opt_bool | opt_hidden,
+ OPT_OFF(queryprogram_router_options_block, expand_cmd_uid) },
+ { "*set_command_group", opt_bool | opt_hidden,
+ OPT_OFF(queryprogram_router_options_block, cmd_gid_set) },
+ { "*set_command_user", opt_bool | opt_hidden,
+ OPT_OFF(queryprogram_router_options_block, cmd_uid_set) },
+ { "command", opt_stringptr,
+ OPT_OFF(queryprogram_router_options_block, command) },
+ { "command_group",opt_expand_gid,
+ OPT_OFF(queryprogram_router_options_block, cmd_gid) },
+ { "command_user", opt_expand_uid,
+ OPT_OFF(queryprogram_router_options_block, cmd_uid) },
+ { "current_directory", opt_stringptr,
+ OPT_OFF(queryprogram_router_options_block, current_directory) },
+ { "timeout", opt_time,
+ OPT_OFF(queryprogram_router_options_block, timeout) }
+};
+
+/* Size of the options list. An extern variable has to be used so that its
+address can appear in the tables drtables.c. */
+
+int queryprogram_router_options_count =
+ sizeof(queryprogram_router_options)/sizeof(optionlist);
+
+
+#ifdef MACRO_PREDEF
+
+/* Dummy entries */
+queryprogram_router_options_block queryprogram_router_option_defaults = {0};
+void queryprogram_router_init(router_instance *rblock) {}
+int queryprogram_router_entry(router_instance *rblock, address_item *addr,
+ struct passwd *pw, int verify, address_item **addr_local,
+ address_item **addr_remote, address_item **addr_new,
+ address_item **addr_succeed) {return 0;}
+
+#else /*!MACRO_PREDEF*/
+
+
+/* Default private options block for the queryprogram router. */
+
+queryprogram_router_options_block queryprogram_router_option_defaults = {
+ NULL, /* command */
+ 60*60, /* timeout */
+ (uid_t)(-1), /* cmd_uid */
+ (gid_t)(-1), /* cmd_gid */
+ FALSE, /* cmd_uid_set */
+ FALSE, /* cmd_gid_set */
+ US"/", /* current_directory */
+ NULL, /* expand_cmd_gid */
+ NULL /* expand_cmd_uid */
+};
+
+
+
+/*************************************************
+* Initialization entry point *
+*************************************************/
+
+/* Called for each instance, after its options have been read, to enable
+consistency checks to be done, or anything else that needs to be set up. */
+
+void
+queryprogram_router_init(router_instance *rblock)
+{
+queryprogram_router_options_block *ob =
+ (queryprogram_router_options_block *)(rblock->options_block);
+
+/* A command must be given */
+
+if (!ob->command)
+ log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s router:\n "
+ "a command specification is required", rblock->name);
+
+/* A uid/gid must be supplied */
+
+if (!ob->cmd_uid_set && !ob->expand_cmd_uid)
+ log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s router:\n "
+ "command_user must be specified", rblock->name);
+}
+
+
+
+/*************************************************
+* Process a set of generated new addresses *
+*************************************************/
+
+/* This function sets up a set of newly generated child addresses and puts them
+on the new address chain.
+
+Arguments:
+ rblock router block
+ addr_new new address chain
+ addr original address
+ generated list of generated addresses
+ addr_prop the propagated data block, containing errors_to,
+ header change stuff, and address_data
+
+Returns: nothing
+*/
+
+static void
+add_generated(router_instance *rblock, address_item **addr_new,
+ address_item *addr, address_item *generated,
+ address_item_propagated *addr_prop)
+{
+while (generated != NULL)
+ {
+ BOOL ignore_error = addr->prop.ignore_error;
+ address_item *next = generated;
+
+ generated = next->next;
+
+ next->parent = addr;
+ next->prop = *addr_prop;
+ next->prop.ignore_error = next->prop.ignore_error || ignore_error;
+ next->start_router = rblock->redirect_router;
+
+ next->next = *addr_new;
+ *addr_new = next;
+
+ if (addr->child_count == USHRT_MAX)
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "%s router generated more than %d "
+ "child addresses for <%s>", rblock->name, USHRT_MAX, addr->address);
+ addr->child_count++;
+
+ DEBUG(D_route)
+ debug_printf("%s router generated %s\n", rblock->name, next->address);
+ }
+}
+
+
+
+
+/*************************************************
+* Main entry point *
+*************************************************/
+
+/* See local README for interface details. This router returns:
+
+DECLINE
+ . DECLINE returned
+ . self = DECLINE
+
+PASS
+ . PASS returned
+ . timeout of host lookup and pass_on_timeout set
+ . self = PASS
+
+DEFER
+ . verifying the errors address caused a deferment or a big disaster such
+ as an expansion failure (rf_get_errors_address)
+ . expanding a headers_{add,remove} string caused a deferment or another
+ expansion error (rf_get_munge_headers)
+ . a problem in rf_get_transport: no transport when one is needed;
+ failed to expand dynamic transport; failed to find dynamic transport
+ . bad lookup type
+ . problem looking up host (rf_lookup_hostlist)
+ . self = DEFER or FREEZE
+ . failure to set up uid/gid for running the command
+ . failure of transport_set_up_command: too many arguments, expansion fail
+ . failure to create child process
+ . child process crashed or timed out or didn't return data
+ . :defer: in data
+ . DEFER or FREEZE returned
+ . problem in redirection data
+ . unknown transport name or trouble expanding router transport
+
+FAIL
+ . :fail: in data
+ . FAIL returned
+ . self = FAIL
+
+OK
+ . address added to addr_local or addr_remote for delivery
+ . new addresses added to addr_new
+*/
+
+int
+queryprogram_router_entry(
+ router_instance *rblock, /* data for this instantiation */
+ address_item *addr, /* address we are working on */
+ struct passwd *pw, /* passwd entry after check_local_user */
+ int verify, /* v_none/v_recipient/v_sender/v_expn */
+ address_item **addr_local, /* add it to this if it's local */
+ address_item **addr_remote, /* add it to this if it's remote */
+ address_item **addr_new, /* put new addresses on here */
+ address_item **addr_succeed) /* put old address here on success */
+{
+int fd_in, fd_out, len, rc;
+pid_t pid;
+struct passwd *upw = NULL;
+uschar buffer[1024];
+const uschar **argvptr;
+uschar *rword, *rdata, *s;
+address_item_propagated addr_prop;
+queryprogram_router_options_block *ob =
+ (queryprogram_router_options_block *)(rblock->options_block);
+uschar *current_directory = ob->current_directory;
+ugid_block ugid;
+uid_t curr_uid = getuid();
+gid_t curr_gid = getgid();
+uid_t uid = ob->cmd_uid;
+gid_t gid = ob->cmd_gid;
+uid_t *puid = &uid;
+gid_t *pgid = &gid;
+
+DEBUG(D_route) debug_printf("%s router called for %s: domain = %s\n",
+ rblock->name, addr->address, addr->domain);
+
+ugid.uid_set = ugid.gid_set = FALSE;
+
+/* Set up the propagated data block with the current address_data and the
+errors address and extra header stuff. */
+
+bzero(&addr_prop, sizeof(addr_prop));
+addr_prop.address_data = deliver_address_data;
+tree_dup((tree_node **)&addr_prop.variables, addr->prop.variables);
+
+rc = rf_get_errors_address(addr, rblock, verify, &addr_prop.errors_address);
+if (rc != OK) return rc;
+
+rc = rf_get_munge_headers(addr, rblock, &addr_prop.extra_headers,
+ &addr_prop.remove_headers);
+if (rc != OK) return rc;
+
+/* Get the fixed or expanded uid under which the command is to run
+(initialization ensures that one or the other is set). */
+
+if ( !ob->cmd_uid_set
+ && !route_find_expanded_user(ob->expand_cmd_uid, rblock->name, US"router",
+ &upw, &uid, &(addr->message)))
+ return DEFER;
+
+/* Get the fixed or expanded gid, or take the gid from the passwd entry. */
+
+if (!ob->cmd_gid_set)
+ if (ob->expand_cmd_gid)
+ {
+ if (route_find_expanded_group(ob->expand_cmd_gid, rblock->name,
+ US"router", &gid, &(addr->message)))
+ return DEFER;
+ }
+ else if (upw)
+ gid = upw->pw_gid;
+ else
+ {
+ addr->message = string_sprintf("command_user set without command_group "
+ "for %s router", rblock->name);
+ return DEFER;
+ }
+
+DEBUG(D_route) debug_printf("requires uid=%ld gid=%ld current_directory=%s\n",
+ (long int)uid, (long int)gid, current_directory);
+
+/* If we are not running as root, we will not be able to change uid/gid. */
+
+if (curr_uid != root_uid && (uid != curr_uid || gid != curr_gid))
+ {
+ DEBUG(D_route)
+ {
+ debug_printf("not running as root: cannot change uid/gid\n");
+ debug_printf("subprocess will run with uid=%ld gid=%ld\n",
+ (long int)curr_uid, (long int)curr_gid);
+ }
+ puid = pgid = NULL;
+ }
+
+/* Set up the command to run */
+
+if (!transport_set_up_command(&argvptr, /* anchor for arg list */
+ ob->command, /* raw command */
+ TRUE, /* expand the arguments */
+ 0, /* not relevant when... */
+ NULL, /* no transporting address */
+ FALSE, /* args must be untainted */
+ US"queryprogram router", /* for error messages */
+ &addr->message)) /* where to put error message */
+ return DEFER;
+
+/* Create the child process, making it a group leader. */
+
+if ((pid = child_open_uid(argvptr, NULL, 0077, puid, pgid, &fd_in, &fd_out,
+ current_directory, TRUE, US"queryprogram-cmd")) < 0)
+ {
+ addr->message = string_sprintf("%s router couldn't create child process: %s",
+ rblock->name, strerror(errno));
+ return DEFER;
+ }
+
+/* Nothing is written to the standard input. */
+
+(void)close(fd_in);
+
+/* Wait for the process to finish, applying the timeout, and inspect its return
+code. */
+
+if ((rc = child_close(pid, ob->timeout)) != 0)
+ {
+ if (rc > 0)
+ addr->message = string_sprintf("%s router: command returned non-zero "
+ "code %d", rblock->name, rc);
+
+ else if (rc == -256)
+ {
+ addr->message = string_sprintf("%s router: command timed out",
+ rblock->name);
+ killpg(pid, SIGKILL); /* Kill the whole process group */
+ }
+
+ else if (rc == -257)
+ addr->message = string_sprintf("%s router: wait() failed: %s",
+ rblock->name, strerror(errno));
+
+ else
+ addr->message = string_sprintf("%s router: command killed by signal %d",
+ rblock->name, -rc);
+
+ return DEFER;
+ }
+
+/* Read the pipe to get the command's output, and then close it. */
+
+len = read(fd_out, buffer, sizeof(buffer) - 1);
+(void)close(fd_out);
+
+/* Failure to return any data is an error. */
+
+if (len <= 0)
+ {
+ addr->message = string_sprintf("%s router: command failed to return data",
+ rblock->name);
+ return DEFER;
+ }
+
+/* Get rid of leading and trailing white space, and pick off the first word of
+the result. */
+
+while (len > 0 && isspace(buffer[len-1])) len--;
+buffer[len] = 0;
+
+DEBUG(D_route) debug_printf("command wrote: %s\n", buffer);
+
+rword = buffer;
+while (isspace(*rword)) rword++;
+rdata = rword;
+while (*rdata && !isspace(*rdata)) rdata++;
+if (*rdata) *rdata++ = 0;
+
+/* The word must be a known yield name. If it is "REDIRECT", the rest of the
+line is redirection data, as for a .forward file. It may not contain filter
+data, and it may not contain anything other than addresses (no files, no pipes,
+no specials). */
+
+if (strcmpic(rword, US"REDIRECT") == 0)
+ {
+ int filtertype;
+ redirect_block redirect;
+ address_item *generated = NULL;
+
+ redirect.string = rdata;
+ redirect.isfile = FALSE;
+
+ rc = rda_interpret(&redirect, /* redirection data */
+ RDO_BLACKHOLE | /* forbid :blackhole: */
+ RDO_FAIL | /* forbid :fail: */
+ RDO_INCLUDE | /* forbid :include: */
+ RDO_REWRITE, /* rewrite generated addresses */
+ NULL, /* :include: directory not relevant */
+ NULL, /* sieve vacation directory not relevant */
+ NULL, /* sieve enotify mailto owner not relevant */
+ NULL, /* sieve useraddress not relevant */
+ NULL, /* sieve subaddress not relevant */
+ &ugid, /* uid/gid (but not set) */
+ &generated, /* where to hang the results */
+ &addr->message, /* where to put messages */
+ NULL, /* don't skip syntax errors */
+ &filtertype, /* not used; will always be FILTER_FORWARD */
+ string_sprintf("%s router", rblock->name));
+
+ switch (rc)
+ {
+ /* FF_DEFER and FF_FAIL can arise only as a result of explicit commands.
+ If a configured message was supplied, allow it to be included in an SMTP
+ response after verifying. */
+
+ case FF_DEFER:
+ if (!addr->message) addr->message = US"forced defer";
+ else addr->user_message = addr->message;
+ return DEFER;
+
+ case FF_FAIL:
+ add_generated(rblock, addr_new, addr, generated, &addr_prop);
+ if (!addr->message) addr->message = US"forced rejection";
+ else addr->user_message = addr->message;
+ return FAIL;
+
+ case FF_DELIVERED:
+ break;
+
+ case FF_NOTDELIVERED: /* an empty redirection list is bad */
+ addr->message = US"no addresses supplied";
+ /* Fall through */
+
+ case FF_ERROR:
+ default:
+ addr->basic_errno = ERRNO_BADREDIRECT;
+ addr->message = string_sprintf("error in redirect data: %s", addr->message);
+ return DEFER;
+ }
+
+ /* Handle the generated addresses, if any. */
+
+ add_generated(rblock, addr_new, addr, generated, &addr_prop);
+
+ /* Put the original address onto the succeed queue so that any retry items
+ that get attached to it get processed. */
+
+ addr->next = *addr_succeed;
+ *addr_succeed = addr;
+
+ return OK;
+ }
+
+/* Handle other returns that are not ACCEPT */
+
+if (strcmpic(rword, US"accept") != 0)
+ {
+ if (strcmpic(rword, US"decline") == 0) return DECLINE;
+ if (strcmpic(rword, US"pass") == 0) return PASS;
+ addr->message = string_copy(rdata); /* data is a message */
+ if (strcmpic(rword, US"fail") == 0)
+ {
+ setflag(addr, af_pass_message);
+ return FAIL;
+ }
+ if (strcmpic(rword, US"freeze") == 0) addr->special_action = SPECIAL_FREEZE;
+ else if (strcmpic(rword, US"defer") != 0)
+ {
+ addr->message = string_sprintf("bad command yield: %s %s", rword, rdata);
+ log_write(0, LOG_PANIC, "%s router: %s", rblock->name, addr->message);
+ }
+ return DEFER;
+ }
+
+/* The command yielded "ACCEPT". The rest of the string is a number of keyed
+fields from which we can fish out values using the equivalent of the "extract"
+expansion function. */
+
+if ((s = expand_getkeyed(US"data", rdata)) && *s)
+ addr_prop.address_data = string_copy(s);
+
+/* If we found a transport name, find the actual transport */
+
+if ((s = expand_getkeyed(US"transport", rdata)) && *s)
+ {
+ transport_instance *transport;
+ for (transport = transports; transport; transport = transport->next)
+ if (Ustrcmp(transport->name, s) == 0) break;
+ if (!transport)
+ {
+ addr->message = string_sprintf("unknown transport name %s yielded by "
+ "command", s);
+ log_write(0, LOG_PANIC, "%s router: %s", rblock->name, addr->message);
+ return DEFER;
+ }
+ addr->transport = transport;
+ }
+
+/* No transport given; get the transport from the router configuration. It may
+be fixed or expanded, but there will be an error if it is unset, requested by
+the last argument not being NULL. */
+
+else
+ {
+ if (!rf_get_transport(rblock->transport_name, &rblock->transport, addr,
+ rblock->name, US"transport"))
+ return DEFER;
+ addr->transport = rblock->transport;
+ }
+
+/* See if a host list is given, and if so, look up the addresses. */
+
+if ((s = expand_getkeyed(US"hosts", rdata)) && *s)
+ {
+ int lookup_type = LK_DEFAULT;
+ uschar * ss = expand_getkeyed(US"lookup", rdata);
+
+ if (ss && *ss)
+ {
+ if (Ustrcmp(ss, "byname") == 0) lookup_type = LK_BYNAME;
+ else if (Ustrcmp(ss, "bydns") == 0) lookup_type = LK_BYDNS;
+ else
+ {
+ addr->message = string_sprintf("bad lookup type \"%s\" yielded by "
+ "command", ss);
+ log_write(0, LOG_PANIC, "%s router: %s", rblock->name, addr->message);
+ return DEFER;
+ }
+ }
+
+ host_build_hostlist(&(addr->host_list), s, FALSE); /* pro tem no randomize */
+
+ rc = rf_lookup_hostlist(rblock, addr, rblock->ignore_target_hosts,
+ lookup_type, hff_defer, addr_new);
+ if (rc != OK) return rc;
+ }
+lookup_value = NULL;
+
+/* Put the errors address, extra headers, and address_data into this address */
+
+addr->prop = addr_prop;
+
+/* Queue the address for local or remote delivery. */
+
+return rf_queue_add(addr, addr_local, addr_remote, rblock, pw) ? OK : DEFER;
+}
+
+#endif /*!MACRO_PREDEF*/
+/* End of routers/queryprogram.c */
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-03 05:51:05 +0000