/*++ /* NAME /* qmgr 3h /* SUMMARY /* queue manager data structures /* SYNOPSIS /* #include "qmgr.h" /* DESCRIPTION /* .nf /* * System library. */ #include #include /* * Utility library. */ #include #include /* * Global library. */ #include #include /* * The queue manager is built around lots of mutually-referring structures. * These typedefs save some typing. */ typedef struct QMGR_TRANSPORT QMGR_TRANSPORT; typedef struct QMGR_QUEUE QMGR_QUEUE; typedef struct QMGR_ENTRY QMGR_ENTRY; typedef struct QMGR_MESSAGE QMGR_MESSAGE; typedef struct QMGR_JOB QMGR_JOB; typedef struct QMGR_PEER QMGR_PEER; typedef struct QMGR_TRANSPORT_LIST QMGR_TRANSPORT_LIST; typedef struct QMGR_QUEUE_LIST QMGR_QUEUE_LIST; typedef struct QMGR_ENTRY_LIST QMGR_ENTRY_LIST; typedef struct QMGR_JOB_LIST QMGR_JOB_LIST; typedef struct QMGR_PEER_LIST QMGR_PEER_LIST; typedef struct QMGR_SCAN QMGR_SCAN; typedef struct QMGR_FEEDBACK QMGR_FEEDBACK; /* * Hairy macros to update doubly-linked lists. */ #define QMGR_LIST_ROTATE(head, object, peers) { \ head.next->peers.prev = head.prev; \ head.prev->peers.next = head.next; \ head.next = object->peers.next; \ head.next->peers.prev = 0; \ head.prev = object; \ object->peers.next = 0; \ } #define QMGR_LIST_UNLINK(head, type, object, peers) { \ type _next = object->peers.next; \ type _prev = object->peers.prev; \ if (_prev) _prev->peers.next = _next; \ else head.next = _next; \ if (_next) _next->peers.prev = _prev; \ else head.prev = _prev; \ object->peers.next = object->peers.prev = 0; \ } #define QMGR_LIST_LINK(head, pred, object, succ, peers) { \ object->peers.prev = pred; \ object->peers.next = succ; \ if (pred) pred->peers.next = object; \ else head.next = object; \ if (succ) succ->peers.prev = object; \ else head.prev = object; \ } #define QMGR_LIST_PREPEND(head, object, peers) { \ object->peers.next = head.next; \ object->peers.prev = 0; \ if (head.next) { \ head.next->peers.prev = object; \ } else { \ head.prev = object; \ } \ head.next = object; \ } #define QMGR_LIST_APPEND(head, object, peers) { \ object->peers.prev = head.prev; \ object->peers.next = 0; \ if (head.prev) { \ head.prev->peers.next = object; \ } else { \ head.next = object; \ } \ head.prev = object; \ } #define QMGR_LIST_INIT(head) { \ head.prev = 0; \ head.next = 0; \ } /* * Transports are looked up by name (when we have resolved a message), or * round-robin wise (when we want to distribute resources fairly). */ struct QMGR_TRANSPORT_LIST { QMGR_TRANSPORT *next; QMGR_TRANSPORT *prev; }; extern struct HTABLE *qmgr_transport_byname; /* transport by name */ extern QMGR_TRANSPORT_LIST qmgr_transport_list; /* transports, round robin */ /* * Delivery agents provide feedback, as hints that Postfix should expend * more or fewer resources on a specific destination domain. The main.cf * file specifies how feedback affects delivery concurrency: add/subtract a * constant, a ratio of constants, or a constant divided by the delivery * concurrency; and it specifies how much feedback must accumulate between * concurrency updates. */ struct QMGR_FEEDBACK { int hysteresis; /* to pass, need to be this tall */ double base; /* pre-computed from main.cf */ int index; /* none, window, sqrt(window) */ }; #define QMGR_FEEDBACK_IDX_NONE 0 /* no window dependence */ #define QMGR_FEEDBACK_IDX_WIN 1 /* 1/window dependence */ #if 0 #define QMGR_FEEDBACK_IDX_SQRT_WIN 2 /* 1/sqrt(window) dependence */ #endif #ifdef QMGR_FEEDBACK_IDX_SQRT_WIN #include #endif extern void qmgr_feedback_init(QMGR_FEEDBACK *, const char *, const char *, const char *, const char *); #ifndef QMGR_FEEDBACK_IDX_SQRT_WIN #define QMGR_FEEDBACK_VAL(fb, win) \ ((fb).index == QMGR_FEEDBACK_IDX_NONE ? (fb).base : (fb).base / (win)) #else #define QMGR_FEEDBACK_VAL(fb, win) \ ((fb).index == QMGR_FEEDBACK_IDX_NONE ? (fb).base : \ (fb).index == QMGR_FEEDBACK_IDX_WIN ? (fb).base / (win) : \ (fb).base / sqrt(win)) #endif /* * Each transport (local, smtp-out, bounce) can have one queue per next hop * name. Queues are looked up by next hop name (when we have resolved a * message destination), or round-robin wise (when we want to deliver * messages fairly). */ struct QMGR_QUEUE_LIST { QMGR_QUEUE *next; QMGR_QUEUE *prev; }; struct QMGR_JOB_LIST { QMGR_JOB *next; QMGR_JOB *prev; }; struct QMGR_TRANSPORT { int flags; /* blocked, etc. */ int pending; /* incomplete DA connections */ char *name; /* transport name */ int dest_concurrency_limit; /* concurrency per domain */ int init_dest_concurrency; /* init. per-domain concurrency */ int recipient_limit; /* recipients per transaction */ int rcpt_per_stack; /* extra slots reserved for jobs put * on the job stack */ int rcpt_unused; /* available in-core recipient slots */ int refill_limit; /* recipient batch size for message * refill */ int refill_delay; /* delay before message refill */ int slot_cost; /* cost of new preemption slot (# of * selected entries) */ int slot_loan; /* preemption boost offset and */ int slot_loan_factor; /* factor, see qmgr_job_preempt() */ int min_slots; /* when preemption can take effect at * all */ struct HTABLE *queue_byname; /* queues indexed by domain */ QMGR_QUEUE_LIST queue_list; /* queues, round robin order */ struct HTABLE *job_byname; /* jobs indexed by queue id */ QMGR_JOB_LIST job_list; /* list of message jobs (1 per * message) ordered by scheduler */ QMGR_JOB_LIST job_bytime; /* jobs ordered by time since queued */ QMGR_JOB *job_current; /* keeps track of the current job */ QMGR_JOB *job_next_unread; /* next job with unread recipients */ QMGR_JOB *candidate_cache; /* cached result from * qmgr_job_candidate() */ QMGR_JOB *candidate_cache_current; /* current job tied to the candidate */ time_t candidate_cache_time; /* when candidate_cache was last * updated */ int blocker_tag; /* for marking blocker jobs */ QMGR_TRANSPORT_LIST peers; /* linkage */ DSN *dsn; /* why unavailable */ QMGR_FEEDBACK pos_feedback; /* positive feedback control */ QMGR_FEEDBACK neg_feedback; /* negative feedback control */ int fail_cohort_limit; /* flow shutdown control */ int xport_rate_delay; /* suspend per delivery */ int rate_delay; /* suspend per delivery */ }; #define QMGR_TRANSPORT_STAT_DEAD (1<<1) #define QMGR_TRANSPORT_STAT_RATE_LOCK (1<<2) typedef void (*QMGR_TRANSPORT_ALLOC_NOTIFY) (QMGR_TRANSPORT *, VSTREAM *); extern QMGR_TRANSPORT *qmgr_transport_select(void); extern void qmgr_transport_alloc(QMGR_TRANSPORT *, QMGR_TRANSPORT_ALLOC_NOTIFY); extern void qmgr_transport_throttle(QMGR_TRANSPORT *, DSN *); extern void qmgr_transport_unthrottle(QMGR_TRANSPORT *); extern QMGR_TRANSPORT *qmgr_transport_create(const char *); extern QMGR_TRANSPORT *qmgr_transport_find(const char *); #define QMGR_TRANSPORT_THROTTLED(t) ((t)->flags & QMGR_TRANSPORT_STAT_DEAD) /* * Each next hop (e.g., a domain name) has its own queue of pending message * transactions. The "todo" queue contains messages that are to be delivered * to this next hop. When a message is elected for transmission, it is moved * from the "todo" queue to the "busy" queue. Messages are taken from the * "todo" queue in round-robin order. */ struct QMGR_ENTRY_LIST { QMGR_ENTRY *next; QMGR_ENTRY *prev; }; struct QMGR_QUEUE { int dflags; /* delivery request options */ time_t last_done; /* last delivery completion */ char *name; /* domain name or address */ char *nexthop; /* domain name */ int todo_refcount; /* queue entries (todo list) */ int busy_refcount; /* queue entries (busy list) */ int window; /* slow open algorithm */ double success; /* accumulated positive feedback */ double failure; /* accumulated negative feedback */ double fail_cohorts; /* pseudo-cohort failure count */ QMGR_TRANSPORT *transport; /* transport linkage */ QMGR_ENTRY_LIST todo; /* todo queue entries */ QMGR_ENTRY_LIST busy; /* messages on the wire */ QMGR_QUEUE_LIST peers; /* neighbor queues */ DSN *dsn; /* why unavailable */ time_t clog_time_to_warn; /* time of last warning */ int blocker_tag; /* tagged if blocks job list */ }; #define QMGR_QUEUE_TODO 1 /* waiting for service */ #define QMGR_QUEUE_BUSY 2 /* recipients on the wire */ extern int qmgr_queue_count; extern QMGR_QUEUE *qmgr_queue_create(QMGR_TRANSPORT *, const char *, const char *); extern void qmgr_queue_done(QMGR_QUEUE *); extern void qmgr_queue_throttle(QMGR_QUEUE *, DSN *); extern void qmgr_queue_unthrottle(QMGR_QUEUE *); extern QMGR_QUEUE *qmgr_queue_find(QMGR_TRANSPORT *, const char *); extern void qmgr_queue_suspend(QMGR_QUEUE *, int); /* * Exclusive queue states. Originally there were only two: "throttled" and * "not throttled". It was natural to encode these in the queue window size. * After 10 years it's not practical to rip out all the working code and * change representations, so we just clean up the names a little. * * Note: only the "ready" state can reach every state (including itself); * non-ready states can reach only the "ready" state. Other transitions are * forbidden, because they would result in dangling event handlers. */ #define QMGR_QUEUE_STAT_THROTTLED 0 /* back-off timer */ #define QMGR_QUEUE_STAT_SUSPENDED -1 /* voluntary delay timer */ #define QMGR_QUEUE_STAT_SAVED -2 /* delayed cleanup timer */ #define QMGR_QUEUE_STAT_BAD -3 /* can't happen */ #define QMGR_QUEUE_READY(q) ((q)->window > 0) #define QMGR_QUEUE_THROTTLED(q) ((q)->window == QMGR_QUEUE_STAT_THROTTLED) #define QMGR_QUEUE_SUSPENDED(q) ((q)->window == QMGR_QUEUE_STAT_SUSPENDED) #define QMGR_QUEUE_SAVED(q) ((q)->window == QMGR_QUEUE_STAT_SAVED) #define QMGR_QUEUE_BAD(q) ((q)->window <= QMGR_QUEUE_STAT_BAD) #define QMGR_QUEUE_STATUS(q) ( \ QMGR_QUEUE_READY(q) ? "ready" : \ QMGR_QUEUE_THROTTLED(q) ? "throttled" : \ QMGR_QUEUE_SUSPENDED(q) ? "suspended" : \ QMGR_QUEUE_SAVED(q) ? "saved" : \ "invalid queue status" \ ) /* * Structure of one next-hop queue entry. In order to save some copying * effort we allow multiple recipients per transaction. */ struct QMGR_ENTRY { VSTREAM *stream; /* delivery process */ QMGR_MESSAGE *message; /* message info */ RECIPIENT_LIST rcpt_list; /* as many as it takes */ QMGR_QUEUE *queue; /* parent linkage */ QMGR_PEER *peer; /* parent linkage */ QMGR_ENTRY_LIST queue_peers; /* per queue neighbor entries */ QMGR_ENTRY_LIST peer_peers; /* per peer neighbor entries */ }; extern QMGR_ENTRY *qmgr_entry_select(QMGR_PEER *); extern void qmgr_entry_unselect(QMGR_ENTRY *); extern void qmgr_entry_move_todo(QMGR_QUEUE *, QMGR_ENTRY *); extern void qmgr_entry_done(QMGR_ENTRY *, int); extern QMGR_ENTRY *qmgr_entry_create(QMGR_PEER *, QMGR_MESSAGE *); /* * All common in-core information about a message is kept here. When all * recipients have been tried the message file is linked to the "deferred" * queue (some hosts not reachable), to the "bounce" queue (some recipients * were rejected), and is then removed from the "active" queue. */ struct QMGR_MESSAGE { int flags; /* delivery problems */ int qflags; /* queuing flags */ int tflags; /* tracing flags */ long tflags_offset; /* offset for killing */ int rflags; /* queue file read flags */ VSTREAM *fp; /* open queue file or null */ int refcount; /* queue entries */ int single_rcpt; /* send one rcpt at a time */ struct timeval arrival_time; /* start of receive transaction */ time_t create_time; /* queue file create time */ struct timeval active_time; /* time of entry into active queue */ time_t queued_time; /* sanitized time when moved to the * active queue */ time_t refill_time; /* sanitized time of last message * refill */ long warn_offset; /* warning bounce flag offset */ time_t warn_time; /* time next warning to be sent */ long data_offset; /* data seek offset */ char *queue_name; /* queue name */ char *queue_id; /* queue file */ char *encoding; /* content encoding */ char *sender; /* complete address */ char *dsn_envid; /* DSN envelope ID */ int dsn_ret; /* DSN headers/full */ int smtputf8; /* requires unicode */ char *verp_delims; /* VERP delimiters */ char *filter_xport; /* filtering transport */ char *inspect_xport; /* inspecting transport */ char *redirect_addr; /* info@spammer.tld */ long data_size; /* data segment size */ long cont_length; /* message content length */ long rcpt_offset; /* more recipients here */ char *client_name; /* client hostname */ char *client_addr; /* client address */ char *client_port; /* client port */ char *client_proto; /* client protocol */ char *client_helo; /* helo parameter */ char *sasl_method; /* SASL method */ char *sasl_username; /* SASL user name */ char *sasl_sender; /* SASL sender */ char *log_ident; /* up-stream queue ID */ char *rewrite_context; /* address qualification */ RECIPIENT_LIST rcpt_list; /* complete addresses */ int rcpt_count; /* used recipient slots */ int rcpt_limit; /* maximum read in-core */ int rcpt_unread; /* # of recipients left in queue file */ QMGR_JOB_LIST job_list; /* jobs delivering this message (1 * per transport) */ }; /* * Flags 0-15 are reserved for qmgr_user.h. */ #define QMGR_READ_FLAG_SEEN_ALL_NON_RCPT (1<<16) #define QMGR_MESSAGE_LOCKED ((QMGR_MESSAGE *) 1) extern int qmgr_message_count; extern int qmgr_recipient_count; extern int qmgr_vrfy_pend_count; extern void qmgr_message_free(QMGR_MESSAGE *); extern void qmgr_message_update_warn(QMGR_MESSAGE *); extern void qmgr_message_kill_record(QMGR_MESSAGE *, long); extern QMGR_MESSAGE *qmgr_message_alloc(const char *, const char *, int, mode_t); extern QMGR_MESSAGE *qmgr_message_realloc(QMGR_MESSAGE *); #define QMGR_MSG_STATS(stats, message) \ MSG_STATS_INIT2(stats, \ incoming_arrival, message->arrival_time, \ active_arrival, message->active_time) /* * Sometimes it's required to access the transport queues and entries on per * message basis. That's what the QMGR_JOB structure is for - it groups all * per message information within each transport using a list of QMGR_PEER * structures. These structures in turn correspond with per message * QMGR_QUEUE structure and list all per message QMGR_ENTRY structures. */ struct QMGR_PEER_LIST { QMGR_PEER *next; QMGR_PEER *prev; }; struct QMGR_JOB { QMGR_MESSAGE *message; /* message delivered by this job */ QMGR_TRANSPORT *transport; /* transport this job belongs to */ QMGR_JOB_LIST message_peers; /* per message neighbor linkage */ QMGR_JOB_LIST transport_peers; /* per transport neighbor linkage */ QMGR_JOB_LIST time_peers; /* by time neighbor linkage */ QMGR_JOB *stack_parent; /* stack parent */ QMGR_JOB_LIST stack_children; /* all stack children */ QMGR_JOB_LIST stack_siblings; /* stack children linkage */ int stack_level; /* job stack nesting level (-1 means * it's not on the lists at all) */ int blocker_tag; /* tagged if blocks the job list */ struct HTABLE *peer_byname; /* message job peers, indexed by * domain */ QMGR_PEER_LIST peer_list; /* list of message job peers */ int slots_used; /* slots used during preemption */ int slots_available; /* slots available for preemption (in * multiples of slot_cost) */ int selected_entries; /* # of entries selected for delivery * so far */ int read_entries; /* # of entries read in-core so far */ int rcpt_count; /* used recipient slots */ int rcpt_limit; /* available recipient slots */ }; struct QMGR_PEER { QMGR_JOB *job; /* job handling this peer */ QMGR_QUEUE *queue; /* queue corresponding with this peer */ int refcount; /* peer entries */ QMGR_ENTRY_LIST entry_list; /* todo message entries queued for * this peer */ QMGR_PEER_LIST peers; /* neighbor linkage */ }; extern QMGR_ENTRY *qmgr_job_entry_select(QMGR_TRANSPORT *); extern QMGR_PEER *qmgr_peer_select(QMGR_JOB *); extern void qmgr_job_blocker_update(QMGR_QUEUE *); extern QMGR_JOB *qmgr_job_obtain(QMGR_MESSAGE *, QMGR_TRANSPORT *); extern void qmgr_job_free(QMGR_JOB *); extern void qmgr_job_move_limits(QMGR_JOB *); extern QMGR_PEER *qmgr_peer_create(QMGR_JOB *, QMGR_QUEUE *); extern QMGR_PEER *qmgr_peer_find(QMGR_JOB *, QMGR_QUEUE *); extern QMGR_PEER *qmgr_peer_obtain(QMGR_JOB *, QMGR_QUEUE *); extern void qmgr_peer_free(QMGR_PEER *); /* * qmgr_defer.c */ extern void qmgr_defer_transport(QMGR_TRANSPORT *, DSN *); extern void qmgr_defer_todo(QMGR_QUEUE *, DSN *); extern void qmgr_defer_recipient(QMGR_MESSAGE *, RECIPIENT *, DSN *); /* * qmgr_bounce.c */ extern void qmgr_bounce_recipient(QMGR_MESSAGE *, RECIPIENT *, DSN *); /* * qmgr_deliver.c */ extern int qmgr_deliver_concurrency; extern void qmgr_deliver(QMGR_TRANSPORT *, VSTREAM *); /* * qmgr_active.c */ extern int qmgr_active_feed(QMGR_SCAN *, const char *); extern void qmgr_active_drain(void); extern void qmgr_active_done(QMGR_MESSAGE *); /* * qmgr_move.c */ extern void qmgr_move(const char *, const char *, time_t); /* * qmgr_enable.c */ extern void qmgr_enable_all(void); extern void qmgr_enable_transport(QMGR_TRANSPORT *); extern void qmgr_enable_queue(QMGR_QUEUE *); /* * Queue scan context. */ struct QMGR_SCAN { char *queue; /* queue name */ int flags; /* private, this run */ int nflags; /* private, next run */ struct SCAN_DIR *handle; /* scan */ }; /* * Flags that control queue scans or destination selection. These are * similar to the QMGR_REQ_XXX request codes. */ #define QMGR_SCAN_START (1<<0) /* start now/restart when done */ #define QMGR_SCAN_ALL (1<<1) /* all queue file time stamps */ #define QMGR_FLUSH_ONCE (1<<2) /* unthrottle once */ #define QMGR_FLUSH_DFXP (1<<3) /* override defer_transports */ #define QMGR_FLUSH_EACH (1<<4) /* unthrottle per message */ #define QMGR_FORCE_EXPIRE (1<<5) /* force-defer and force-expire */ /* * qmgr_scan.c */ extern QMGR_SCAN *qmgr_scan_create(const char *); extern void qmgr_scan_request(QMGR_SCAN *, int); extern char *qmgr_scan_next(QMGR_SCAN *); /* * qmgr_error.c */ extern QMGR_TRANSPORT *qmgr_error_transport(const char *); extern QMGR_QUEUE *qmgr_error_queue(const char *, DSN *); extern char *qmgr_error_nexthop(DSN *); /* 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 /* /* Wietse Venema /* Google, Inc. /* 111 8th Avenue /* New York, NY 10011, USA /* /* Preemptive scheduler enhancements: /* Patrik Rak /* Modra 6 /* 155 00, Prague, Czech Republic /*--*/