Mercurial > hg > nginx
view src/event/ngx_event_timer.h @ 8085:043006e5a0b1
SSL: optimized rotation of session ticket keys.
Instead of syncing keys with shared memory on each ticket operation,
the code now does this only when the worker is going to change expiration
of the current key, or going to switch to a new key: that is, usually
at most once per second.
To do so without races, the code maintains 3 keys: current, previous,
and next. If a worker will switch to the next key earlier, other workers
will still be able to decrypt new tickets, since they will be encrypted
with the next key.
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Wed, 12 Oct 2022 20:14:55 +0300 |
parents | 3069dd358ba2 |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_EVENT_TIMER_H_INCLUDED_ #define _NGX_EVENT_TIMER_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #define NGX_TIMER_INFINITE (ngx_msec_t) -1 #define NGX_TIMER_LAZY_DELAY 300 ngx_int_t ngx_event_timer_init(ngx_log_t *log); ngx_msec_t ngx_event_find_timer(void); void ngx_event_expire_timers(void); ngx_int_t ngx_event_no_timers_left(void); extern ngx_rbtree_t ngx_event_timer_rbtree; static ngx_inline void ngx_event_del_timer(ngx_event_t *ev) { ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0, "event timer del: %d: %M", ngx_event_ident(ev->data), ev->timer.key); ngx_rbtree_delete(&ngx_event_timer_rbtree, &ev->timer); #if (NGX_DEBUG) ev->timer.left = NULL; ev->timer.right = NULL; ev->timer.parent = NULL; #endif ev->timer_set = 0; } static ngx_inline void ngx_event_add_timer(ngx_event_t *ev, ngx_msec_t timer) { ngx_msec_t key; ngx_msec_int_t diff; key = ngx_current_msec + timer; if (ev->timer_set) { /* * Use a previous timer value if difference between it and a new * value is less than NGX_TIMER_LAZY_DELAY milliseconds: this allows * to minimize the rbtree operations for fast connections. */ diff = (ngx_msec_int_t) (key - ev->timer.key); if (ngx_abs(diff) < NGX_TIMER_LAZY_DELAY) { ngx_log_debug3(NGX_LOG_DEBUG_EVENT, ev->log, 0, "event timer: %d, old: %M, new: %M", ngx_event_ident(ev->data), ev->timer.key, key); return; } ngx_del_timer(ev); } ev->timer.key = key; ngx_log_debug3(NGX_LOG_DEBUG_EVENT, ev->log, 0, "event timer add: %d: %M:%M", ngx_event_ident(ev->data), timer, ev->timer.key); ngx_rbtree_insert(&ngx_event_timer_rbtree, &ev->timer); ev->timer_set = 1; } #endif /* _NGX_EVENT_TIMER_H_INCLUDED_ */