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Diffstat (limited to 'src/qmgr/qmgr_deliver.c')
| -rw-r--r-- | src/qmgr/qmgr_deliver.c | 456 |
1 files changed, 456 insertions, 0 deletions
diff --git a/src/qmgr/qmgr_deliver.c b/src/qmgr/qmgr_deliver.c new file mode 100644 index 0000000..07e89d4 --- /dev/null +++ b/src/qmgr/qmgr_deliver.c @@ -0,0 +1,456 @@ +/*++ +/* NAME +/* qmgr_deliver 3 +/* SUMMARY +/* deliver one per-site queue entry to that site +/* SYNOPSIS +/* #include "qmgr.h" +/* +/* int qmgr_deliver_concurrency; +/* +/* int qmgr_deliver(transport, fp) +/* QMGR_TRANSPORT *transport; +/* VSTREAM *fp; +/* DESCRIPTION +/* This module implements the client side of the `queue manager +/* to delivery agent' protocol. The queue manager uses +/* asynchronous I/O so that it can drive multiple delivery +/* agents in parallel. Depending on the outcome of a delivery +/* attempt, the status of messages, queues and transports is +/* updated. +/* +/* qmgr_deliver_concurrency is a global counter that says how +/* many delivery processes are in use. This can be used, for +/* example, to control the size of the `active' message queue. +/* +/* qmgr_deliver() executes when a delivery process announces its +/* availability for the named transport. It arranges for delivery +/* of a suitable queue entry. The \fIfp\fR argument specifies a +/* stream that is connected to a delivery process, or a null +/* pointer if the transport accepts no connection. Upon completion +/* of delivery (successful or not), the stream is closed, so that the +/* delivery process is released. +/* DIAGNOSTICS +/* LICENSE +/* .ad +/* .fi +/* The Secure Mailer license must be distributed with this software. +/* AUTHOR(S) +/* Wietse Venema +/* IBM T.J. Watson Research +/* P.O. Box 704 +/* Yorktown Heights, NY 10598, USA +/* +/* Preemptive scheduler enhancements: +/* Patrik Rak +/* Modra 6 +/* 155 00, Prague, Czech Republic +/* +/* Wietse Venema +/* Google, Inc. +/* 111 8th Avenue +/* New York, NY 10011, USA +/*--*/ + +/* System library. */ + +#include <sys_defs.h> +#include <time.h> +#include <string.h> + +/* Utility library. */ + +#include <msg.h> +#include <vstring.h> +#include <vstream.h> +#include <vstring_vstream.h> +#include <events.h> +#include <iostuff.h> +#include <stringops.h> +#include <mymalloc.h> + +/* Global library. */ + +#include <mail_queue.h> +#include <mail_proto.h> +#include <recipient_list.h> +#include <mail_params.h> +#include <deliver_request.h> +#include <verp_sender.h> +#include <dsn_util.h> +#include <dsn_buf.h> +#include <dsb_scan.h> +#include <rcpt_print.h> +#include <smtputf8.h> + +/* Application-specific. */ + +#include "qmgr.h" + + /* + * Important note on the _transport_rate_delay implementation: after + * qmgr_transport_alloc() sets the QMGR_TRANSPORT_STAT_RATE_LOCK flag, all + * code paths must directly or indirectly invoke qmgr_transport_unthrottle() + * or qmgr_transport_throttle(). Otherwise, transports with non-zero + * _transport_rate_delay will become stuck. + */ + +int qmgr_deliver_concurrency; + + /* + * Message delivery status codes. + */ +#define DELIVER_STAT_OK 0 /* all recipients delivered */ +#define DELIVER_STAT_DEFER 1 /* try some recipients later */ +#define DELIVER_STAT_CRASH 2 /* mailer internal problem */ + +/* qmgr_deliver_initial_reply - retrieve initial delivery process response */ + +static int qmgr_deliver_initial_reply(VSTREAM *stream) +{ + if (peekfd(vstream_fileno(stream)) < 0) { + msg_warn("%s: premature disconnect", VSTREAM_PATH(stream)); + return (DELIVER_STAT_CRASH); + } else if (attr_scan(stream, ATTR_FLAG_STRICT, + RECV_ATTR_STREQ(MAIL_ATTR_PROTO, MAIL_ATTR_PROTO_DELIVER), + ATTR_TYPE_END) != 0) { + msg_warn("%s: malformed response", VSTREAM_PATH(stream)); + return (DELIVER_STAT_DEFER); + } else { + return (0); + } +} + +/* qmgr_deliver_final_reply - retrieve final delivery process response */ + +static int qmgr_deliver_final_reply(VSTREAM *stream, DSN_BUF *dsb) +{ + int stat; + + if (peekfd(vstream_fileno(stream)) < 0) { + msg_warn("%s: premature disconnect", VSTREAM_PATH(stream)); + return (DELIVER_STAT_CRASH); + } else if (attr_scan(stream, ATTR_FLAG_STRICT, + RECV_ATTR_FUNC(dsb_scan, (void *) dsb), + RECV_ATTR_INT(MAIL_ATTR_STATUS, &stat), + ATTR_TYPE_END) != 2) { + msg_warn("%s: malformed response", VSTREAM_PATH(stream)); + return (DELIVER_STAT_CRASH); + } else { + return (stat ? DELIVER_STAT_DEFER : 0); + } +} + +/* qmgr_deliver_send_request - send delivery request to delivery process */ + +static int qmgr_deliver_send_request(QMGR_ENTRY *entry, VSTREAM *stream) +{ + RECIPIENT_LIST list = entry->rcpt_list; + RECIPIENT *recipient; + QMGR_MESSAGE *message = entry->message; + VSTRING *sender_buf = 0; + MSG_STATS stats; + char *sender; + int flags; + int smtputf8 = message->smtputf8; + const char *addr; + + /* + * Todo: integrate with code up-stream that builds the delivery request. + */ + for (recipient = list.info; recipient < list.info + list.len; recipient++) + if (var_smtputf8_enable && (addr = recipient->address)[0] + && !allascii(addr) && valid_utf8_string(addr, strlen(addr))) { + smtputf8 |= SMTPUTF8_FLAG_RECIPIENT; + if (message->verp_delims) + smtputf8 |= SMTPUTF8_FLAG_SENDER; + } + + /* + * If variable envelope return path is requested, change prefix+@origin + * into prefix+user=domain@origin. Note that with VERP there is only one + * recipient per delivery. + */ + if (message->verp_delims == 0) { + sender = message->sender; + } else { + sender_buf = vstring_alloc(100); + verp_sender(sender_buf, message->verp_delims, + message->sender, list.info); + sender = vstring_str(sender_buf); + } + + flags = message->tflags + | entry->queue->dflags + | (message->inspect_xport ? DEL_REQ_FLAG_BOUNCE : DEL_REQ_FLAG_DEFLT); + (void) QMGR_MSG_STATS(&stats, message); + attr_print(stream, ATTR_FLAG_NONE, + SEND_ATTR_INT(MAIL_ATTR_FLAGS, flags), + SEND_ATTR_STR(MAIL_ATTR_QUEUE, message->queue_name), + SEND_ATTR_STR(MAIL_ATTR_QUEUEID, message->queue_id), + SEND_ATTR_LONG(MAIL_ATTR_OFFSET, message->data_offset), + SEND_ATTR_LONG(MAIL_ATTR_SIZE, message->cont_length), + SEND_ATTR_STR(MAIL_ATTR_NEXTHOP, entry->queue->nexthop), + SEND_ATTR_STR(MAIL_ATTR_ENCODING, message->encoding), + SEND_ATTR_INT(MAIL_ATTR_SMTPUTF8, smtputf8), + SEND_ATTR_STR(MAIL_ATTR_SENDER, sender), + SEND_ATTR_STR(MAIL_ATTR_DSN_ENVID, message->dsn_envid), + SEND_ATTR_INT(MAIL_ATTR_DSN_RET, message->dsn_ret), + SEND_ATTR_FUNC(msg_stats_print, (const void *) &stats), + /* XXX Should be encapsulated with ATTR_TYPE_FUNC. */ + SEND_ATTR_STR(MAIL_ATTR_LOG_CLIENT_NAME, message->client_name), + SEND_ATTR_STR(MAIL_ATTR_LOG_CLIENT_ADDR, message->client_addr), + SEND_ATTR_STR(MAIL_ATTR_LOG_CLIENT_PORT, message->client_port), + SEND_ATTR_STR(MAIL_ATTR_LOG_PROTO_NAME, message->client_proto), + SEND_ATTR_STR(MAIL_ATTR_LOG_HELO_NAME, message->client_helo), + /* XXX Should be encapsulated with ATTR_TYPE_FUNC. */ + SEND_ATTR_STR(MAIL_ATTR_SASL_METHOD, message->sasl_method), + SEND_ATTR_STR(MAIL_ATTR_SASL_USERNAME, message->sasl_username), + SEND_ATTR_STR(MAIL_ATTR_SASL_SENDER, message->sasl_sender), + /* XXX Ditto if we want to pass TLS certificate info. */ + SEND_ATTR_STR(MAIL_ATTR_LOG_IDENT, message->log_ident), + SEND_ATTR_STR(MAIL_ATTR_RWR_CONTEXT, message->rewrite_context), + SEND_ATTR_INT(MAIL_ATTR_RCPT_COUNT, list.len), + ATTR_TYPE_END); + if (sender_buf != 0) + vstring_free(sender_buf); + for (recipient = list.info; recipient < list.info + list.len; recipient++) + attr_print(stream, ATTR_FLAG_NONE, + SEND_ATTR_FUNC(rcpt_print, (const void *) recipient), + ATTR_TYPE_END); + if (vstream_fflush(stream) != 0) { + msg_warn("write to process (%s): %m", entry->queue->transport->name); + return (-1); + } else { + if (msg_verbose) + msg_info("qmgr_deliver: site `%s'", entry->queue->name); + return (0); + } +} + +/* qmgr_deliver_abort - transport response watchdog */ + +static void qmgr_deliver_abort(int unused_event, void *context) +{ + QMGR_ENTRY *entry = (QMGR_ENTRY *) context; + QMGR_QUEUE *queue = entry->queue; + QMGR_TRANSPORT *transport = queue->transport; + QMGR_MESSAGE *message = entry->message; + + msg_fatal("%s: timeout receiving delivery status from transport: %s", + message->queue_id, transport->name); +} + +/* qmgr_deliver_update - process delivery status report */ + +static void qmgr_deliver_update(int unused_event, void *context) +{ + QMGR_ENTRY *entry = (QMGR_ENTRY *) context; + QMGR_QUEUE *queue = entry->queue; + QMGR_TRANSPORT *transport = queue->transport; + QMGR_MESSAGE *message = entry->message; + static DSN_BUF *dsb; + int status; + + /* + * Release the delivery agent from a "hot" queue entry. + */ +#define QMGR_DELIVER_RELEASE_AGENT(entry) do { \ + event_disable_readwrite(vstream_fileno(entry->stream)); \ + (void) vstream_fclose(entry->stream); \ + entry->stream = 0; \ + qmgr_deliver_concurrency--; \ + } while (0) + + if (dsb == 0) + dsb = dsb_create(); + + /* + * The message transport has responded. Stop the watchdog timer. + */ + event_cancel_timer(qmgr_deliver_abort, context); + + /* + * Retrieve the delivery agent status report. The numerical status code + * indicates if delivery should be tried again. The reason text is sent + * only when a site should be avoided for a while, so that the queue + * manager can log why it does not even try to schedule delivery to the + * affected recipients. + */ + status = qmgr_deliver_final_reply(entry->stream, dsb); + + /* + * The mail delivery process failed for some reason (although delivery + * may have been successful). Back off with this transport type for a + * while. Dispose of queue entries for this transport that await + * selection (the todo lists). Stay away from queue entries that have + * been selected (the busy lists), or we would have dangling pointers. + * The queue itself won't go away before we dispose of the current queue + * entry. + */ + if (status == DELIVER_STAT_CRASH) { + message->flags |= DELIVER_STAT_DEFER; +#if 0 + whatsup = concatenate("unknown ", transport->name, + " mail transport error", (char *) 0); + qmgr_transport_throttle(transport, + DSN_SIMPLE(&dsb->dsn, "4.3.0", whatsup)); + myfree(whatsup); +#else + qmgr_transport_throttle(transport, + DSN_SIMPLE(&dsb->dsn, "4.3.0", + "unknown mail transport error")); +#endif + msg_warn("transport %s failure -- see a previous warning/fatal/panic logfile record for the problem description", + transport->name); + + /* + * Assume the worst and write a defer logfile record for each + * recipient. This omission was already present in the first queue + * manager implementation of 199703, and was fixed 200511. + * + * To avoid the synchronous qmgr_defer_recipient() operation for each + * recipient of this queue entry, release the delivery process and + * move the entry back to the todo queue. Let qmgr_defer_transport() + * log the recipient asynchronously if possible, and get out of here. + * Note: if asynchronous logging is not possible, + * qmgr_defer_transport() eventually invokes qmgr_entry_done() and + * the entry becomes a dangling pointer. + */ + QMGR_DELIVER_RELEASE_AGENT(entry); + qmgr_entry_unselect(entry); + qmgr_defer_transport(transport, &dsb->dsn); + return; + } + + /* + * This message must be tried again. + * + * If we have a problem talking to this site, back off with this site for a + * while; dispose of queue entries for this site that await selection + * (the todo list); stay away from queue entries that have been selected + * (the busy list), or we would have dangling pointers. The queue itself + * won't go away before we dispose of the current queue entry. + * + * XXX Caution: DSN_COPY() will panic on empty status or reason. + */ +#define SUSPENDED "delivery temporarily suspended: " + + if (status == DELIVER_STAT_DEFER) { + message->flags |= DELIVER_STAT_DEFER; + if (VSTRING_LEN(dsb->status)) { + /* Sanitize the DSN status/reason from the delivery agent. */ + if (!dsn_valid(vstring_str(dsb->status))) + vstring_strcpy(dsb->status, "4.0.0"); + if (VSTRING_LEN(dsb->reason) == 0) + vstring_strcpy(dsb->reason, "unknown error"); + vstring_prepend(dsb->reason, SUSPENDED, sizeof(SUSPENDED) - 1); + if (QMGR_QUEUE_READY(queue)) { + qmgr_queue_throttle(queue, DSN_FROM_DSN_BUF(dsb)); + if (QMGR_QUEUE_THROTTLED(queue)) + qmgr_defer_todo(queue, &dsb->dsn); + } + } + } + + /* + * No problems detected. Mark the transport and queue as alive. The queue + * itself won't go away before we dispose of the current queue entry. + */ + if (status != DELIVER_STAT_CRASH) { + qmgr_transport_unthrottle(transport); + if (VSTRING_LEN(dsb->reason) == 0) + qmgr_queue_unthrottle(queue); + } + + /* + * Release the delivery process, and give some other queue entry a chance + * to be delivered. When all recipients for a message have been tried, + * decide what to do next with this message: defer, bounce, delete. + */ + QMGR_DELIVER_RELEASE_AGENT(entry); + qmgr_entry_done(entry, QMGR_QUEUE_BUSY); +} + +/* qmgr_deliver - deliver one per-site queue entry */ + +void qmgr_deliver(QMGR_TRANSPORT *transport, VSTREAM *stream) +{ + QMGR_ENTRY *entry; + DSN dsn; + + /* + * Find out if this delivery process is really available. Once elected, + * the delivery process is supposed to express its happiness. If there is + * a problem, wipe the pending deliveries for this transport. This + * routine runs in response to an external event, so it does not run + * while some other queue manipulation is happening. + */ + if (stream == 0 || qmgr_deliver_initial_reply(stream) != 0) { +#if 0 + whatsup = concatenate(transport->name, + " mail transport unavailable", (char *) 0); + qmgr_transport_throttle(transport, + DSN_SIMPLE(&dsn, "4.3.0", whatsup)); + myfree(whatsup); +#else + qmgr_transport_throttle(transport, + DSN_SIMPLE(&dsn, "4.3.0", + "mail transport unavailable")); +#endif + qmgr_defer_transport(transport, &dsn); + if (stream) + (void) vstream_fclose(stream); + return; + } + + /* + * Find a suitable queue entry. Things may have changed since this + * transport was allocated. If no suitable entry is found, + * unceremoniously disconnect from the delivery process. The delivery + * agent request reading routine is prepared for the queue manager to + * change its mind for no apparent reason. + */ + if ((entry = qmgr_job_entry_select(transport)) == 0) { + (void) vstream_fclose(stream); + return; + } + + /* + * Send the queue file info and recipient info to the delivery process. + * If there is a problem, wipe the pending deliveries for this transport. + * This routine runs in response to an external event, so it does not run + * while some other queue manipulation is happening. + */ + if (qmgr_deliver_send_request(entry, stream) < 0) { + qmgr_entry_unselect(entry); +#if 0 + whatsup = concatenate(transport->name, + " mail transport unavailable", (char *) 0); + qmgr_transport_throttle(transport, + DSN_SIMPLE(&dsn, "4.3.0", whatsup)); + myfree(whatsup); +#else + qmgr_transport_throttle(transport, + DSN_SIMPLE(&dsn, "4.3.0", + "mail transport unavailable")); +#endif + qmgr_defer_transport(transport, &dsn); + /* warning: entry may be a dangling pointer here */ + (void) vstream_fclose(stream); + return; + } + + /* + * If we get this far, go wait for the delivery status report. + */ + qmgr_deliver_concurrency++; + entry->stream = stream; + event_enable_read(vstream_fileno(stream), + qmgr_deliver_update, (void *) entry); + + /* + * Guard against broken systems. + */ + event_request_timer(qmgr_deliver_abort, (void *) entry, var_daemon_timeout); +} |