blob: 93f93dfc28bf7c56d4ae994a2503da75d98990b6 [file] [log] [blame]
/*
* Health-checks functions.
*
* Copyright 2000-2009 Willy Tarreau <w@1wt.eu>
* Copyright 2007-2009 Krzysztof Piotr Oledzki <ole@ans.pl>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
*/
#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <common/chunk.h>
#include <common/compat.h>
#include <common/config.h>
#include <common/mini-clist.h>
#include <common/standard.h>
#include <common/time.h>
#include <types/global.h>
#include <proto/backend.h>
#include <proto/checks.h>
#include <proto/fd.h>
#include <proto/log.h>
#include <proto/queue.h>
#include <proto/port_range.h>
#include <proto/proto_http.h>
#include <proto/proto_tcp.h>
#include <proto/proxy.h>
#include <proto/server.h>
#include <proto/session.h>
#include <proto/stream_interface.h>
#include <proto/task.h>
static int httpchk_expect(struct server *s, int done);
static const struct check_status check_statuses[HCHK_STATUS_SIZE] = {
[HCHK_STATUS_UNKNOWN] = { SRV_CHK_UNKNOWN, "UNK", "Unknown" },
[HCHK_STATUS_INI] = { SRV_CHK_UNKNOWN, "INI", "Initializing" },
[HCHK_STATUS_START] = { /* SPECIAL STATUS*/ },
[HCHK_STATUS_HANA] = { SRV_CHK_ERROR, "HANA", "Health analyze" },
[HCHK_STATUS_SOCKERR] = { SRV_CHK_ERROR, "SOCKERR", "Socket error" },
[HCHK_STATUS_L4OK] = { SRV_CHK_RUNNING, "L4OK", "Layer4 check passed" },
[HCHK_STATUS_L4TOUT] = { SRV_CHK_ERROR, "L4TOUT", "Layer4 timeout" },
[HCHK_STATUS_L4CON] = { SRV_CHK_ERROR, "L4CON", "Layer4 connection problem" },
[HCHK_STATUS_L6OK] = { SRV_CHK_RUNNING, "L6OK", "Layer6 check passed" },
[HCHK_STATUS_L6TOUT] = { SRV_CHK_ERROR, "L6TOUT", "Layer6 timeout" },
[HCHK_STATUS_L6RSP] = { SRV_CHK_ERROR, "L6RSP", "Layer6 invalid response" },
[HCHK_STATUS_L7TOUT] = { SRV_CHK_ERROR, "L7TOUT", "Layer7 timeout" },
[HCHK_STATUS_L7RSP] = { SRV_CHK_ERROR, "L7RSP", "Layer7 invalid response" },
[HCHK_STATUS_L57DATA] = { /* DUMMY STATUS */ },
[HCHK_STATUS_L7OKD] = { SRV_CHK_RUNNING, "L7OK", "Layer7 check passed" },
[HCHK_STATUS_L7OKCD] = { SRV_CHK_RUNNING | SRV_CHK_DISABLE, "L7OKC", "Layer7 check conditionally passed" },
[HCHK_STATUS_L7STS] = { SRV_CHK_ERROR, "L7STS", "Layer7 wrong status" },
};
static const struct analyze_status analyze_statuses[HANA_STATUS_SIZE] = { /* 0: ignore, 1: error, 2: OK */
[HANA_STATUS_UNKNOWN] = { "Unknown", { 0, 0 }},
[HANA_STATUS_L4_OK] = { "L4 successful connection", { 2, 0 }},
[HANA_STATUS_L4_ERR] = { "L4 unsuccessful connection", { 1, 1 }},
[HANA_STATUS_HTTP_OK] = { "Correct http response", { 0, 2 }},
[HANA_STATUS_HTTP_STS] = { "Wrong http response", { 0, 1 }},
[HANA_STATUS_HTTP_HDRRSP] = { "Invalid http response (headers)", { 0, 1 }},
[HANA_STATUS_HTTP_RSP] = { "Invalid http response", { 0, 1 }},
[HANA_STATUS_HTTP_READ_ERROR] = { "Read error (http)", { 0, 1 }},
[HANA_STATUS_HTTP_READ_TIMEOUT] = { "Read timeout (http)", { 0, 1 }},
[HANA_STATUS_HTTP_BROKEN_PIPE] = { "Close from server (http)", { 0, 1 }},
};
/*
* Convert check_status code to description
*/
const char *get_check_status_description(short check_status) {
const char *desc;
if (check_status < HCHK_STATUS_SIZE)
desc = check_statuses[check_status].desc;
else
desc = NULL;
if (desc && *desc)
return desc;
else
return check_statuses[HCHK_STATUS_UNKNOWN].desc;
}
/*
* Convert check_status code to short info
*/
const char *get_check_status_info(short check_status) {
const char *info;
if (check_status < HCHK_STATUS_SIZE)
info = check_statuses[check_status].info;
else
info = NULL;
if (info && *info)
return info;
else
return check_statuses[HCHK_STATUS_UNKNOWN].info;
}
const char *get_analyze_status(short analyze_status) {
const char *desc;
if (analyze_status < HANA_STATUS_SIZE)
desc = analyze_statuses[analyze_status].desc;
else
desc = NULL;
if (desc && *desc)
return desc;
else
return analyze_statuses[HANA_STATUS_UNKNOWN].desc;
}
#define SSP_O_HCHK 0x0002
static void server_status_printf(struct chunk *msg, struct server *s, unsigned options, int xferred) {
if (s->track)
chunk_printf(msg, " via %s/%s",
s->track->proxy->id, s->track->id);
if (options & SSP_O_HCHK) {
chunk_printf(msg, ", reason: %s", get_check_status_description(s->check_status));
if (s->check_status >= HCHK_STATUS_L57DATA)
chunk_printf(msg, ", code: %d", s->check_code);
if (*s->check_desc) {
struct chunk src;
chunk_printf(msg, ", info: \"");
chunk_initlen(&src, s->check_desc, 0, strlen(s->check_desc));
chunk_asciiencode(msg, &src, '"');
chunk_printf(msg, "\"");
}
if (s->check_duration >= 0)
chunk_printf(msg, ", check duration: %ldms", s->check_duration);
}
if (xferred >= 0) {
if (!(s->state & SRV_RUNNING))
chunk_printf(msg, ". %d active and %d backup servers left.%s"
" %d sessions active, %d requeued, %d remaining in queue",
s->proxy->srv_act, s->proxy->srv_bck,
(s->proxy->srv_bck && !s->proxy->srv_act) ? " Running on backup." : "",
s->cur_sess, xferred, s->nbpend);
else
chunk_printf(msg, ". %d active and %d backup servers online.%s"
" %d sessions requeued, %d total in queue",
s->proxy->srv_act, s->proxy->srv_bck,
(s->proxy->srv_bck && !s->proxy->srv_act) ? " Running on backup." : "",
xferred, s->nbpend);
}
}
/*
* Set s->check_status, update s->check_duration and fill s->result with
* an adequate SRV_CHK_* value.
*
* Show information in logs about failed health check if server is UP
* or succeeded health checks if server is DOWN.
*/
static void set_server_check_status(struct server *s, short status, char *desc) {
struct chunk msg;
if (status == HCHK_STATUS_START) {
s->result = SRV_CHK_UNKNOWN; /* no result yet */
s->check_desc[0] = '\0';
s->check_start = now;
return;
}
if (!s->check_status)
return;
if (desc && *desc) {
strncpy(s->check_desc, desc, HCHK_DESC_LEN-1);
s->check_desc[HCHK_DESC_LEN-1] = '\0';
} else
s->check_desc[0] = '\0';
s->check_status = status;
if (check_statuses[status].result)
s->result = check_statuses[status].result;
if (status == HCHK_STATUS_HANA)
s->check_duration = -1;
else if (!tv_iszero(&s->check_start)) {
/* set_server_check_status() may be called more than once */
s->check_duration = tv_ms_elapsed(&s->check_start, &now);
tv_zero(&s->check_start);
}
if (s->proxy->options2 & PR_O2_LOGHCHKS &&
(((s->health != 0) && (s->result & SRV_CHK_ERROR)) ||
((s->health != s->rise + s->fall - 1) && (s->result & SRV_CHK_RUNNING)) ||
((s->state & SRV_GOINGDOWN) && !(s->result & SRV_CHK_DISABLE)) ||
(!(s->state & SRV_GOINGDOWN) && (s->result & SRV_CHK_DISABLE)))) {
int health, rise, fall, state;
chunk_init(&msg, trash, trashlen);
/* FIXME begin: calculate local version of the health/rise/fall/state */
health = s->health;
rise = s->rise;
fall = s->fall;
state = s->state;
if (s->result & SRV_CHK_ERROR) {
if (health > rise) {
health--; /* still good */
} else {
if (health == rise)
state &= ~(SRV_RUNNING | SRV_GOINGDOWN);
health = 0;
}
}
if (s->result & SRV_CHK_RUNNING) {
if (health < rise + fall - 1) {
health++; /* was bad, stays for a while */
if (health == rise)
state |= SRV_RUNNING;
if (health >= rise)
health = rise + fall - 1; /* OK now */
}
/* clear consecutive_errors if observing is enabled */
if (s->onerror)
s->consecutive_errors = 0;
}
/* FIXME end: calculate local version of the health/rise/fall/state */
chunk_printf(&msg,
"Health check for %sserver %s/%s %s%s",
s->state & SRV_BACKUP ? "backup " : "",
s->proxy->id, s->id,
(s->result & SRV_CHK_DISABLE)?"conditionally ":"",
(s->result & SRV_CHK_RUNNING)?"succeeded":"failed");
server_status_printf(&msg, s, SSP_O_HCHK, -1);
chunk_printf(&msg, ", status: %d/%d %s",
(state & SRV_RUNNING) ? (health - rise + 1) : (health),
(state & SRV_RUNNING) ? (fall) : (rise),
(state & SRV_RUNNING)?"UP":"DOWN");
Warning("%s.\n", trash);
send_log(s->proxy, LOG_NOTICE, "%s.\n", trash);
}
}
/* sends a log message when a backend goes down, and also sets last
* change date.
*/
static void set_backend_down(struct proxy *be)
{
be->last_change = now.tv_sec;
be->down_trans++;
Alert("%s '%s' has no server available!\n", proxy_type_str(be), be->id);
send_log(be, LOG_EMERG, "%s %s has no server available!\n", proxy_type_str(be), be->id);
}
/* Redistribute pending connections when a server goes down. The number of
* connections redistributed is returned.
*/
static int redistribute_pending(struct server *s)
{
struct pendconn *pc, *pc_bck, *pc_end;
int xferred = 0;
FOREACH_ITEM_SAFE(pc, pc_bck, &s->pendconns, pc_end, struct pendconn *, list) {
struct session *sess = pc->sess;
if ((sess->be->options & (PR_O_REDISP|PR_O_PERSIST)) == PR_O_REDISP &&
!(sess->flags & SN_FORCE_PRST)) {
/* The REDISP option was specified. We will ignore
* cookie and force to balance or use the dispatcher.
*/
/* it's left to the dispatcher to choose a server */
sess->flags &= ~(SN_DIRECT | SN_ASSIGNED | SN_ADDR_SET);
pendconn_free(pc);
task_wakeup(sess->task, TASK_WOKEN_RES);
xferred++;
}
}
return xferred;
}
/* Check for pending connections at the backend, and assign some of them to
* the server coming up. The server's weight is checked before being assigned
* connections it may not be able to handle. The total number of transferred
* connections is returned.
*/
static int check_for_pending(struct server *s)
{
int xferred;
if (!s->eweight)
return 0;
for (xferred = 0; !s->maxconn || xferred < srv_dynamic_maxconn(s); xferred++) {
struct session *sess;
struct pendconn *p;
p = pendconn_from_px(s->proxy);
if (!p)
break;
set_target_server(&p->sess->target, s);
sess = p->sess;
pendconn_free(p);
task_wakeup(sess->task, TASK_WOKEN_RES);
}
return xferred;
}
/* Shutdown all connections of a server. The caller must pass a termination
* code in <why>, which must be one of SN_ERR_* indicating the reason for the
* shutdown.
*/
static void shutdown_sessions(struct server *srv, int why)
{
struct session *session, *session_bck;
list_for_each_entry_safe(session, session_bck, &srv->actconns, by_srv)
if (session->srv_conn == srv)
session_shutdown(session, why);
}
/* Shutdown all connections of all backup servers of a proxy. The caller must
* pass a termination code in <why>, which must be one of SN_ERR_* indicating
* the reason for the shutdown.
*/
static void shutdown_backup_sessions(struct proxy *px, int why)
{
struct server *srv;
for (srv = px->srv; srv != NULL; srv = srv->next)
if (srv->state & SRV_BACKUP)
shutdown_sessions(srv, why);
}
/* Sets server <s> down, notifies by all available means, recounts the
* remaining servers on the proxy and transfers queued sessions whenever
* possible to other servers. It automatically recomputes the number of
* servers, but not the map.
*/
void set_server_down(struct server *s)
{
struct server *srv;
struct chunk msg;
int xferred;
if (s->state & SRV_MAINTAIN) {
s->health = s->rise;
}
if (s->health == s->rise || s->track) {
int srv_was_paused = s->state & SRV_GOINGDOWN;
int prev_srv_count = s->proxy->srv_bck + s->proxy->srv_act;
s->last_change = now.tv_sec;
s->state &= ~(SRV_RUNNING | SRV_GOINGDOWN);
if (s->proxy->lbprm.set_server_status_down)
s->proxy->lbprm.set_server_status_down(s);
if (s->onmarkeddown & HANA_ONMARKEDDOWN_SHUTDOWNSESSIONS)
shutdown_sessions(s, SN_ERR_DOWN);
/* we might have sessions queued on this server and waiting for
* a connection. Those which are redispatchable will be queued
* to another server or to the proxy itself.
*/
xferred = redistribute_pending(s);
chunk_init(&msg, trash, trashlen);
if (s->state & SRV_MAINTAIN) {
chunk_printf(&msg,
"%sServer %s/%s is DOWN for maintenance", s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
} else {
chunk_printf(&msg,
"%sServer %s/%s is DOWN", s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
server_status_printf(&msg, s,
((!s->track && !(s->proxy->options2 & PR_O2_LOGHCHKS))?SSP_O_HCHK:0),
xferred);
}
Warning("%s.\n", trash);
/* we don't send an alert if the server was previously paused */
if (srv_was_paused)
send_log(s->proxy, LOG_NOTICE, "%s.\n", trash);
else
send_log(s->proxy, LOG_ALERT, "%s.\n", trash);
if (prev_srv_count && s->proxy->srv_bck == 0 && s->proxy->srv_act == 0)
set_backend_down(s->proxy);
s->counters.down_trans++;
if (s->state & SRV_CHECKED)
for(srv = s->tracknext; srv; srv = srv->tracknext)
if (! (srv->state & SRV_MAINTAIN))
/* Only notify tracking servers that are not already in maintenance. */
set_server_down(srv);
}
s->health = 0; /* failure */
}
void set_server_up(struct server *s) {
struct server *srv;
struct chunk msg;
int xferred;
unsigned int old_state = s->state;
if (s->state & SRV_MAINTAIN) {
s->health = s->rise;
}
if (s->health == s->rise || s->track) {
if (s->proxy->srv_bck == 0 && s->proxy->srv_act == 0) {
if (s->proxy->last_change < now.tv_sec) // ignore negative times
s->proxy->down_time += now.tv_sec - s->proxy->last_change;
s->proxy->last_change = now.tv_sec;
}
if (s->last_change < now.tv_sec) // ignore negative times
s->down_time += now.tv_sec - s->last_change;
s->last_change = now.tv_sec;
s->state |= SRV_RUNNING;
s->state &= ~SRV_MAINTAIN;
if (s->slowstart > 0) {
s->state |= SRV_WARMINGUP;
if (s->proxy->lbprm.algo & BE_LB_PROP_DYN) {
/* For dynamic algorithms, start at the first step of the weight,
* without multiplying by BE_WEIGHT_SCALE.
*/
s->eweight = s->uweight;
if (s->proxy->lbprm.update_server_eweight)
s->proxy->lbprm.update_server_eweight(s);
}
task_schedule(s->warmup, tick_add(now_ms, MS_TO_TICKS(MAX(1000, s->slowstart / 20))));
}
if (s->proxy->lbprm.set_server_status_up)
s->proxy->lbprm.set_server_status_up(s);
/* If the server is set with "on-marked-up shutdown-backup-sessions",
* and it's not a backup server and its effective weight is > 0,
* then it can accept new connections, so we shut down all sessions
* on all backup servers.
*/
if ((s->onmarkedup & HANA_ONMARKEDUP_SHUTDOWNBACKUPSESSIONS) &&
!(s->state & SRV_BACKUP) && s->eweight)
shutdown_backup_sessions(s->proxy, SN_ERR_UP);
/* check if we can handle some connections queued at the proxy. We
* will take as many as we can handle.
*/
xferred = check_for_pending(s);
chunk_init(&msg, trash, trashlen);
if (old_state & SRV_MAINTAIN) {
chunk_printf(&msg,
"%sServer %s/%s is UP (leaving maintenance)", s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
} else {
chunk_printf(&msg,
"%sServer %s/%s is UP", s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
server_status_printf(&msg, s,
((!s->track && !(s->proxy->options2 & PR_O2_LOGHCHKS))?SSP_O_HCHK:0),
xferred);
}
Warning("%s.\n", trash);
send_log(s->proxy, LOG_NOTICE, "%s.\n", trash);
if (s->state & SRV_CHECKED)
for(srv = s->tracknext; srv; srv = srv->tracknext)
if (! (srv->state & SRV_MAINTAIN))
/* Only notify tracking servers if they're not in maintenance. */
set_server_up(srv);
}
if (s->health >= s->rise)
s->health = s->rise + s->fall - 1; /* OK now */
}
static void set_server_disabled(struct server *s) {
struct server *srv;
struct chunk msg;
int xferred;
s->state |= SRV_GOINGDOWN;
if (s->proxy->lbprm.set_server_status_down)
s->proxy->lbprm.set_server_status_down(s);
/* we might have sessions queued on this server and waiting for
* a connection. Those which are redispatchable will be queued
* to another server or to the proxy itself.
*/
xferred = redistribute_pending(s);
chunk_init(&msg, trash, trashlen);
chunk_printf(&msg,
"Load-balancing on %sServer %s/%s is disabled",
s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
server_status_printf(&msg, s,
((!s->track && !(s->proxy->options2 & PR_O2_LOGHCHKS))?SSP_O_HCHK:0),
xferred);
Warning("%s.\n", trash);
send_log(s->proxy, LOG_NOTICE, "%s.\n", trash);
if (!s->proxy->srv_bck && !s->proxy->srv_act)
set_backend_down(s->proxy);
if (s->state & SRV_CHECKED)
for(srv = s->tracknext; srv; srv = srv->tracknext)
set_server_disabled(srv);
}
static void set_server_enabled(struct server *s) {
struct server *srv;
struct chunk msg;
int xferred;
s->state &= ~SRV_GOINGDOWN;
if (s->proxy->lbprm.set_server_status_up)
s->proxy->lbprm.set_server_status_up(s);
/* check if we can handle some connections queued at the proxy. We
* will take as many as we can handle.
*/
xferred = check_for_pending(s);
chunk_init(&msg, trash, trashlen);
chunk_printf(&msg,
"Load-balancing on %sServer %s/%s is enabled again",
s->state & SRV_BACKUP ? "Backup " : "",
s->proxy->id, s->id);
server_status_printf(&msg, s,
((!s->track && !(s->proxy->options2 & PR_O2_LOGHCHKS))?SSP_O_HCHK:0),
xferred);
Warning("%s.\n", trash);
send_log(s->proxy, LOG_NOTICE, "%s.\n", trash);
if (s->state & SRV_CHECKED)
for(srv = s->tracknext; srv; srv = srv->tracknext)
set_server_enabled(srv);
}
void health_adjust(struct server *s, short status) {
int failed;
int expire;
/* return now if observing nor health check is not enabled */
if (!s->observe || !s->check)
return;
if (s->observe >= HANA_OBS_SIZE)
return;
if (status >= HCHK_STATUS_SIZE || !analyze_statuses[status].desc)
return;
switch (analyze_statuses[status].lr[s->observe - 1]) {
case 1:
failed = 1;
break;
case 2:
failed = 0;
break;
default:
return;
}
if (!failed) {
/* good: clear consecutive_errors */
s->consecutive_errors = 0;
return;
}
s->consecutive_errors++;
if (s->consecutive_errors < s->consecutive_errors_limit)
return;
sprintf(trash, "Detected %d consecutive errors, last one was: %s",
s->consecutive_errors, get_analyze_status(status));
switch (s->onerror) {
case HANA_ONERR_FASTINTER:
/* force fastinter - nothing to do here as all modes force it */
break;
case HANA_ONERR_SUDDTH:
/* simulate a pre-fatal failed health check */
if (s->health > s->rise)
s->health = s->rise + 1;
/* no break - fall through */
case HANA_ONERR_FAILCHK:
/* simulate a failed health check */
set_server_check_status(s, HCHK_STATUS_HANA, trash);
if (s->health > s->rise) {
s->health--; /* still good */
s->counters.failed_checks++;
}
else
set_server_down(s);
break;
case HANA_ONERR_MARKDWN:
/* mark server down */
s->health = s->rise;
set_server_check_status(s, HCHK_STATUS_HANA, trash);
set_server_down(s);
break;
default:
/* write a warning? */
break;
}
s->consecutive_errors = 0;
s->counters.failed_hana++;
if (s->fastinter) {
expire = tick_add(now_ms, MS_TO_TICKS(s->fastinter));
if (s->check->expire > expire)
s->check->expire = expire;
}
}
static int httpchk_build_status_header(struct server *s, char *buffer)
{
int sv_state;
int ratio;
int hlen = 0;
const char *srv_hlt_st[7] = { "DOWN", "DOWN %d/%d",
"UP %d/%d", "UP",
"NOLB %d/%d", "NOLB",
"no check" };
memcpy(buffer + hlen, "X-Haproxy-Server-State: ", 24);
hlen += 24;
if (!(s->state & SRV_CHECKED))
sv_state = 6; /* should obviously never happen */
else if (s->state & SRV_RUNNING) {
if (s->health == s->rise + s->fall - 1)
sv_state = 3; /* UP */
else
sv_state = 2; /* going down */
if (s->state & SRV_GOINGDOWN)
sv_state += 2;
} else {
if (s->health)
sv_state = 1; /* going up */
else
sv_state = 0; /* DOWN */
}
hlen += sprintf(buffer + hlen,
srv_hlt_st[sv_state],
(s->state & SRV_RUNNING) ? (s->health - s->rise + 1) : (s->health),
(s->state & SRV_RUNNING) ? (s->fall) : (s->rise));
hlen += sprintf(buffer + hlen, "; name=%s/%s; node=%s; weight=%d/%d; scur=%d/%d; qcur=%d",
s->proxy->id, s->id,
global.node,
(s->eweight * s->proxy->lbprm.wmult + s->proxy->lbprm.wdiv - 1) / s->proxy->lbprm.wdiv,
(s->proxy->lbprm.tot_weight * s->proxy->lbprm.wmult + s->proxy->lbprm.wdiv - 1) / s->proxy->lbprm.wdiv,
s->cur_sess, s->proxy->beconn - s->proxy->nbpend,
s->nbpend);
if ((s->state & SRV_WARMINGUP) &&
now.tv_sec < s->last_change + s->slowstart &&
now.tv_sec >= s->last_change) {
ratio = MAX(1, 100 * (now.tv_sec - s->last_change) / s->slowstart);
hlen += sprintf(buffer + hlen, "; throttle=%d%%", ratio);
}
buffer[hlen++] = '\r';
buffer[hlen++] = '\n';
return hlen;
}
/*
* This function is used only for server health-checks. It handles
* the connection acknowledgement. If the proxy requires L7 health-checks,
* it sends the request. In other cases, it calls set_server_check_status()
* to set s->check_status, s->check_duration and s->result.
*/
static void event_srv_chk_w(int fd)
{
__label__ out_wakeup, out_nowake, out_poll, out_error;
struct task *t = fdtab[fd].owner;
struct server *s = t->context;
if (unlikely((s->check_conn->flags & CO_FL_ERROR) || (fdtab[fd].ev & FD_POLL_ERR))) {
int skerr, err = errno;
socklen_t lskerr = sizeof(skerr);
if (!getsockopt(fd, SOL_SOCKET, SO_ERROR, &skerr, &lskerr) && skerr)
err = skerr;
set_server_check_status(s, HCHK_STATUS_L4CON, strerror(err));
goto out_error;
}
/* here, we know that the connection is established */
if (!(s->result & SRV_CHK_ERROR)) {
/* we don't want to mark 'UP' a server on which we detected an error earlier */
if (s->proxy->options2 & PR_O2_CHK_ANY) {
int ret;
const char *check_req = s->proxy->check_req;
int check_len = s->proxy->check_len;
/* we want to check if this host replies to HTTP or SSLv3 requests
* so we'll send the request, and won't wake the checker up now.
*/
if ((s->proxy->options2 & PR_O2_CHK_ANY) == PR_O2_SSL3_CHK) {
/* SSL requires that we put Unix time in the request */
int gmt_time = htonl(date.tv_sec);
memcpy(s->proxy->check_req + 11, &gmt_time, 4);
}
else if ((s->proxy->options2 & PR_O2_CHK_ANY) == PR_O2_HTTP_CHK) {
memcpy(trash, check_req, check_len);
if (s->proxy->options2 & PR_O2_CHK_SNDST)
check_len += httpchk_build_status_header(s, trash + check_len);
trash[check_len++] = '\r';
trash[check_len++] = '\n';
trash[check_len] = '\0';
check_req = trash;
}
ret = send(fd, check_req, check_len, MSG_DONTWAIT | MSG_NOSIGNAL);
if (ret == check_len) {
/* we allow up to <timeout.check> if nonzero for a responce */
if (s->proxy->timeout.check) {
t->expire = tick_add_ifset(now_ms, s->proxy->timeout.check);
task_queue(t);
}
fd_want_recv(fd); /* prepare for reading reply */
goto out_nowake;
}
else if (ret == 0 || errno == EAGAIN)
goto out_poll;
else {
switch (errno) {
case ECONNREFUSED:
case ENETUNREACH:
set_server_check_status(s, HCHK_STATUS_L4CON, strerror(errno));
break;
default:
set_server_check_status(s, HCHK_STATUS_SOCKERR, strerror(errno));
}
goto out_error;
}
}
else {
/* We have no data to send to check the connection, and
* getsockopt() will not inform us whether the connection
* is still pending. So we'll reuse connect() to check the
* state of the socket. This has the advantage of givig us
* the following info :
* - error
* - connecting (EALREADY, EINPROGRESS)
* - connected (EISCONN, 0)
*/
struct sockaddr_storage sa;
if (is_addr(&s->check_addr))
sa = s->check_addr;
else
sa = s->addr;
set_host_port(&sa, s->check_port);
if (connect(fd, (struct sockaddr *)&sa, get_addr_len(&sa)) == 0)
errno = 0;
if (errno == EALREADY || errno == EINPROGRESS)
goto out_poll;
if (errno && errno != EISCONN) {
set_server_check_status(s, HCHK_STATUS_L4CON, strerror(errno));
goto out_error;
}
/* good TCP connection is enough */
set_server_check_status(s, HCHK_STATUS_L4OK, NULL);
goto out_wakeup;
}
}
out_wakeup:
task_wakeup(t, TASK_WOKEN_IO);
out_nowake:
fd_stop_send(fd); /* nothing more to write */
fdtab[fd].ev &= ~FD_POLL_OUT;
return;
out_poll:
/* The connection is still pending. We'll have to poll it
* before attempting to go further. */
fdtab[fd].ev &= ~FD_POLL_OUT;
fd_poll_send(fd);
return;
out_error:
s->check_conn->flags |= CO_FL_ERROR;
goto out_wakeup;
}
/*
* This function is used only for server health-checks. It handles the server's
* reply to an HTTP request, SSL HELLO or MySQL client Auth. It calls
* set_server_check_status() to update s->check_status, s->check_duration
* and s->result.
* The set_server_check_status function is called with HCHK_STATUS_L7OKD if
* an HTTP server replies HTTP 2xx or 3xx (valid responses), if an SMTP server
* returns 2xx, HCHK_STATUS_L6OK if an SSL server returns at least 5 bytes in
* response to an SSL HELLO (the principle is that this is enough to
* distinguish between an SSL server and a pure TCP relay). All other cases will
* call it with a proper error status like HCHK_STATUS_L7STS, HCHK_STATUS_L6RSP,
* etc.
*/
static void event_srv_chk_r(int fd)
{
__label__ out_wakeup;
int len;
struct task *t = fdtab[fd].owner;
struct server *s = t->context;
char *desc;
int done;
unsigned short msglen;
if (unlikely((s->result & SRV_CHK_ERROR) || (s->check_conn->flags & CO_FL_ERROR))) {
/* in case of TCP only, this tells us if the connection failed */
if (!(s->result & SRV_CHK_ERROR))
set_server_check_status(s, HCHK_STATUS_SOCKERR, NULL);
goto out_wakeup;
}
/* Warning! Linux returns EAGAIN on SO_ERROR if data are still available
* but the connection was closed on the remote end. Fortunately, recv still
* works correctly and we don't need to do the getsockopt() on linux.
*/
/* Set buffer to point to the end of the data already read, and check
* that there is free space remaining. If the buffer is full, proceed
* with running the checks without attempting another socket read.
*/
done = 0;
for (len = 0; s->check_data_len < global.tune.chksize; s->check_data_len += len) {
len = recv(fd, s->check_data + s->check_data_len, global.tune.chksize - s->check_data_len, 0);
if (len <= 0)
break;
}
if (len == 0)
done = 1; /* connection hangup received */
else if (len < 0 && errno != EAGAIN) {
/* Report network errors only if we got no other data. Otherwise
* we'll let the upper layers decide whether the response is OK
* or not. It is very common that an RST sent by the server is
* reported as an error just after the last data chunk.
*/
done = 1;
if (!s->check_data_len) {
if (!(s->result & SRV_CHK_ERROR))
set_server_check_status(s, HCHK_STATUS_SOCKERR, NULL);
goto out_wakeup;
}
}
/* Intermediate or complete response received.
* Terminate string in check_data buffer.
*/
if (s->check_data_len < global.tune.chksize)
s->check_data[s->check_data_len] = '\0';
else {
s->check_data[s->check_data_len - 1] = '\0';
done = 1; /* buffer full, don't wait for more data */
}
/* Run the checks... */
switch (s->proxy->options2 & PR_O2_CHK_ANY) {
case PR_O2_HTTP_CHK:
if (!done && s->check_data_len < strlen("HTTP/1.0 000\r"))
goto wait_more_data;
/* Check if the server speaks HTTP 1.X */
if ((s->check_data_len < strlen("HTTP/1.0 000\r")) ||
(memcmp(s->check_data, "HTTP/1.", 7) != 0 ||
(*(s->check_data + 12) != ' ' && *(s->check_data + 12) != '\r')) ||
!isdigit((unsigned char) *(s->check_data + 9)) || !isdigit((unsigned char) *(s->check_data + 10)) ||
!isdigit((unsigned char) *(s->check_data + 11))) {
cut_crlf(s->check_data);
set_server_check_status(s, HCHK_STATUS_L7RSP, s->check_data);
goto out_wakeup;
}
s->check_code = str2uic(s->check_data + 9);
desc = ltrim(s->check_data + 12, ' ');
if ((s->proxy->options & PR_O_DISABLE404) &&
(s->state & SRV_RUNNING) && (s->check_code == 404)) {
/* 404 may be accepted as "stopping" only if the server was up */
cut_crlf(desc);
set_server_check_status(s, HCHK_STATUS_L7OKCD, desc);
}
else if (s->proxy->options2 & PR_O2_EXP_TYPE) {
/* Run content verification check... We know we have at least 13 chars */
if (!httpchk_expect(s, done))
goto wait_more_data;
}
/* check the reply : HTTP/1.X 2xx and 3xx are OK */
else if (*(s->check_data + 9) == '2' || *(s->check_data + 9) == '3') {
cut_crlf(desc);
set_server_check_status(s, HCHK_STATUS_L7OKD, desc);
}
else {
cut_crlf(desc);
set_server_check_status(s, HCHK_STATUS_L7STS, desc);
}
break;
case PR_O2_SSL3_CHK:
if (!done && s->check_data_len < 5)
goto wait_more_data;
/* Check for SSLv3 alert or handshake */
if ((s->check_data_len >= 5) && (*s->check_data == 0x15 || *s->check_data == 0x16))
set_server_check_status(s, HCHK_STATUS_L6OK, NULL);
else
set_server_check_status(s, HCHK_STATUS_L6RSP, NULL);
break;
case PR_O2_SMTP_CHK:
if (!done && s->check_data_len < strlen("000\r"))
goto wait_more_data;
/* Check if the server speaks SMTP */
if ((s->check_data_len < strlen("000\r")) ||
(*(s->check_data + 3) != ' ' && *(s->check_data + 3) != '\r') ||
!isdigit((unsigned char) *s->check_data) || !isdigit((unsigned char) *(s->check_data + 1)) ||
!isdigit((unsigned char) *(s->check_data + 2))) {
cut_crlf(s->check_data);
set_server_check_status(s, HCHK_STATUS_L7RSP, s->check_data);
goto out_wakeup;
}
s->check_code = str2uic(s->check_data);
desc = ltrim(s->check_data + 3, ' ');
cut_crlf(desc);
/* Check for SMTP code 2xx (should be 250) */
if (*s->check_data == '2')
set_server_check_status(s, HCHK_STATUS_L7OKD, desc);
else
set_server_check_status(s, HCHK_STATUS_L7STS, desc);
break;
case PR_O2_PGSQL_CHK:
if (!done && s->check_data_len < 9)
goto wait_more_data;
if (s->check_data[0] == 'R') {
set_server_check_status(s, HCHK_STATUS_L7OKD, "PostgreSQL server is ok");
}
else {
if ((s->check_data[0] == 'E') && (s->check_data[5]!=0) && (s->check_data[6]!=0))
desc = &s->check_data[6];
else
desc = "PostgreSQL unknown error";
set_server_check_status(s, HCHK_STATUS_L7STS, desc);
}
break;
case PR_O2_REDIS_CHK:
if (!done && s->check_data_len < 7)
goto wait_more_data;
if (strcmp(s->check_data, "+PONG\r\n") == 0) {
set_server_check_status(s, HCHK_STATUS_L7OKD, "Redis server is ok");
}
else {
set_server_check_status(s, HCHK_STATUS_L7STS, s->check_data);
}
break;
case PR_O2_MYSQL_CHK:
if (!done && s->check_data_len < 5)
goto wait_more_data;
if (s->proxy->check_len == 0) { // old mode
if (*(s->check_data + 4) != '\xff') {
/* We set the MySQL Version in description for information purpose
* FIXME : it can be cool to use MySQL Version for other purpose,
* like mark as down old MySQL server.
*/
if (s->check_data_len > 51) {
desc = ltrim(s->check_data + 5, ' ');
set_server_check_status(s, HCHK_STATUS_L7OKD, desc);
}
else {
if (!done)
goto wait_more_data;
/* it seems we have a OK packet but without a valid length,
* it must be a protocol error
*/
set_server_check_status(s, HCHK_STATUS_L7RSP, s->check_data);
}
}
else {
/* An error message is attached in the Error packet */
desc = ltrim(s->check_data + 7, ' ');
set_server_check_status(s, HCHK_STATUS_L7STS, desc);
}
} else {
unsigned int first_packet_len = ((unsigned int) *s->check_data) +
(((unsigned int) *(s->check_data + 1)) << 8) +
(((unsigned int) *(s->check_data + 2)) << 16);
if (s->check_data_len == first_packet_len + 4) {
/* MySQL Error packet always begin with field_count = 0xff */
if (*(s->check_data + 4) != '\xff') {
/* We have only one MySQL packet and it is a Handshake Initialization packet
* but we need to have a second packet to know if it is alright
*/
if (!done && s->check_data_len < first_packet_len + 5)
goto wait_more_data;
}
else {
/* We have only one packet and it is an Error packet,
* an error message is attached, so we can display it
*/
desc = &s->check_data[7];
//Warning("onlyoneERR: %s\n", desc);
set_server_check_status(s, HCHK_STATUS_L7STS, desc);
}
} else if (s->check_data_len > first_packet_len + 4) {
unsigned int second_packet_len = ((unsigned int) *(s->check_data + first_packet_len + 4)) +
(((unsigned int) *(s->check_data + first_packet_len + 5)) << 8) +
(((unsigned int) *(s->check_data + first_packet_len + 6)) << 16);
if (s->check_data_len == first_packet_len + 4 + second_packet_len + 4 ) {
/* We have 2 packets and that's good */
/* Check if the second packet is a MySQL Error packet or not */
if (*(s->check_data + first_packet_len + 8) != '\xff') {
/* No error packet */
/* We set the MySQL Version in description for information purpose */
desc = &s->check_data[5];
//Warning("2packetOK: %s\n", desc);
set_server_check_status(s, HCHK_STATUS_L7OKD, desc);
}
else {
/* An error message is attached in the Error packet
* so we can display it ! :)
*/
desc = &s->check_data[first_packet_len+11];
//Warning("2packetERR: %s\n", desc);
set_server_check_status(s, HCHK_STATUS_L7STS, desc);
}
}
}
else {
if (!done)
goto wait_more_data;
/* it seems we have a Handshake Initialization packet but without a valid length,
* it must be a protocol error
*/
desc = &s->check_data[5];
//Warning("protoerr: %s\n", desc);
set_server_check_status(s, HCHK_STATUS_L7RSP, desc);
}
}
break;
case PR_O2_LDAP_CHK:
if (!done && s->check_data_len < 14)
goto wait_more_data;
/* Check if the server speaks LDAP (ASN.1/BER)
* http://en.wikipedia.org/wiki/Basic_Encoding_Rules
* http://tools.ietf.org/html/rfc4511
*/
/* http://tools.ietf.org/html/rfc4511#section-4.1.1
* LDAPMessage: 0x30: SEQUENCE
*/
if ((s->check_data_len < 14) || (*(s->check_data) != '\x30')) {
set_server_check_status(s, HCHK_STATUS_L7RSP, "Not LDAPv3 protocol");
}
else {
/* size of LDAPMessage */
msglen = (*(s->check_data + 1) & 0x80) ? (*(s->check_data + 1) & 0x7f) : 0;
/* http://tools.ietf.org/html/rfc4511#section-4.2.2
* messageID: 0x02 0x01 0x01: INTEGER 1
* protocolOp: 0x61: bindResponse
*/
if ((msglen > 2) ||
(memcmp(s->check_data + 2 + msglen, "\x02\x01\x01\x61", 4) != 0)) {
set_server_check_status(s, HCHK_STATUS_L7RSP, "Not LDAPv3 protocol");
goto out_wakeup;
}
/* size of bindResponse */
msglen += (*(s->check_data + msglen + 6) & 0x80) ? (*(s->check_data + msglen + 6) & 0x7f) : 0;
/* http://tools.ietf.org/html/rfc4511#section-4.1.9
* ldapResult: 0x0a 0x01: ENUMERATION
*/
if ((msglen > 4) ||
(memcmp(s->check_data + 7 + msglen, "\x0a\x01", 2) != 0)) {
set_server_check_status(s, HCHK_STATUS_L7RSP, "Not LDAPv3 protocol");
goto out_wakeup;
}
/* http://tools.ietf.org/html/rfc4511#section-4.1.9
* resultCode
*/
s->check_code = *(s->check_data + msglen + 9);
if (s->check_code) {
set_server_check_status(s, HCHK_STATUS_L7STS, "See RFC: http://tools.ietf.org/html/rfc4511#section-4.1.9");
} else {
set_server_check_status(s, HCHK_STATUS_L7OKD, "Success");
}
}
break;
default:
/* other checks are valid if the connection succeeded anyway */
set_server_check_status(s, HCHK_STATUS_L4OK, NULL);
break;
} /* switch */
out_wakeup:
if (s->result & SRV_CHK_ERROR)
s->check_conn->flags |= CO_FL_ERROR;
/* Reset the check buffer... */
*s->check_data = '\0';
s->check_data_len = 0;
/* Close the connection... */
shutdown(fd, SHUT_RDWR);
fd_stop_recv(fd);
task_wakeup(t, TASK_WOKEN_IO);
fdtab[fd].ev &= ~FD_POLL_IN;
return;
wait_more_data:
fdtab[fd].ev &= ~FD_POLL_IN;
fd_poll_recv(fd);
}
/* I/O call back for the health checks. Returns 0. */
static int check_iocb(int fd)
{
int e;
if (!fdtab[fd].owner)
return 0;
e = fdtab[fd].ev;
if (e & (FD_POLL_IN | FD_POLL_HUP | FD_POLL_ERR))
event_srv_chk_r(fd);
if (e & (FD_POLL_OUT | FD_POLL_ERR))
event_srv_chk_w(fd);
return 0;
}
/*
* updates the server's weight during a warmup stage. Once the final weight is
* reached, the task automatically stops. Note that any server status change
* must have updated s->last_change accordingly.
*/
static struct task *server_warmup(struct task *t)
{
struct server *s = t->context;
/* by default, plan on stopping the task */
t->expire = TICK_ETERNITY;
if ((s->state & (SRV_RUNNING|SRV_WARMINGUP|SRV_MAINTAIN)) != (SRV_RUNNING|SRV_WARMINGUP))
return t;
if (now.tv_sec < s->last_change || now.tv_sec >= s->last_change + s->slowstart) {
/* go to full throttle if the slowstart interval is reached */
s->state &= ~SRV_WARMINGUP;
if (s->proxy->lbprm.algo & BE_LB_PROP_DYN)
s->eweight = s->uweight * BE_WEIGHT_SCALE;
if (s->proxy->lbprm.update_server_eweight)
s->proxy->lbprm.update_server_eweight(s);
}
else if (s->proxy->lbprm.algo & BE_LB_PROP_DYN) {
/* for dynamic algorithms, let's slowly update the weight */
s->eweight = (BE_WEIGHT_SCALE * (now.tv_sec - s->last_change) +
s->slowstart - 1) / s->slowstart;
s->eweight *= s->uweight;
if (s->proxy->lbprm.update_server_eweight)
s->proxy->lbprm.update_server_eweight(s);
}
/* Note that static algorithms are already running at full throttle */
/* probably that we can refill this server with a bit more connections */
check_for_pending(s);
/* get back there in 1 second or 1/20th of the slowstart interval,
* whichever is greater, resulting in small 5% steps.
*/
if (s->state & SRV_WARMINGUP)
t->expire = tick_add(now_ms, MS_TO_TICKS(MAX(1000, s->slowstart / 20)));
return t;
}
/*
* manages a server health-check. Returns
* the time the task accepts to wait, or TIME_ETERNITY for infinity.
*/
static struct task *process_chk(struct task *t)
{
int attempts = 0;
struct server *s = t->context;
struct sockaddr_storage sa;
int fd;
int rv;
new_chk:
if (attempts++ > 0) {
/* we always fail to create a server, let's stop insisting... */
while (tick_is_expired(t->expire, now_ms))
t->expire = tick_add(t->expire, MS_TO_TICKS(s->inter));
return t;
}
fd = s->curfd;
if (fd < 0) { /* no check currently running */
if (!tick_is_expired(t->expire, now_ms)) /* woke up too early */
return t;
/* we don't send any health-checks when the proxy is stopped or when
* the server should not be checked.
*/
if (!(s->state & SRV_CHECKED) || s->proxy->state == PR_STSTOPPED || (s->state & SRV_MAINTAIN)) {
while (tick_is_expired(t->expire, now_ms))
t->expire = tick_add(t->expire, MS_TO_TICKS(s->inter));
return t;
}
/* we'll initiate a new check */
set_server_check_status(s, HCHK_STATUS_START, NULL);
if ((fd = socket(s->addr.ss_family, SOCK_STREAM, IPPROTO_TCP)) != -1) {
if ((fd < global.maxsock) &&
(fcntl(fd, F_SETFL, O_NONBLOCK) != -1) &&
(setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, (char *) &one, sizeof(one)) != -1)) {
//fprintf(stderr, "process_chk: 3\n");
if (s->proxy->options & PR_O_TCP_NOLING) {
/* We don't want to useless data */
setsockopt(fd, SOL_SOCKET, SO_LINGER, (struct linger *) &nolinger, sizeof(struct linger));
}
if (is_addr(&s->check_addr))
/* we'll connect to the check addr specified on the server */
sa = s->check_addr;
else
/* we'll connect to the addr on the server */
sa = s->addr;
set_host_port(&sa, s->check_port);
/* allow specific binding :
* - server-specific at first
* - proxy-specific next
*/
if (s->state & SRV_BIND_SRC) {
struct sockaddr_storage *remote = NULL;
int ret, flags = 0;
#if defined(CONFIG_HAP_CTTPROXY) || defined(CONFIG_HAP_LINUX_TPROXY)
if ((s->state & SRV_TPROXY_MASK) == SRV_TPROXY_ADDR) {
remote = &s->tproxy_addr;
flags = 3;
}
#endif
#ifdef SO_BINDTODEVICE
/* Note: this might fail if not CAP_NET_RAW */
if (s->iface_name)
setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
s->iface_name, s->iface_len + 1);
#endif
if (s->sport_range) {
int bind_attempts = 10; /* should be more than enough to find a spare port */
struct sockaddr_storage src;
ret = 1;
src = s->source_addr;
do {
/* note: in case of retry, we may have to release a previously
* allocated port, hence this loop's construct.
*/
port_range_release_port(fdinfo[fd].port_range, fdinfo[fd].local_port);
fdinfo[fd].port_range = NULL;
if (!bind_attempts)
break;
bind_attempts--;
fdinfo[fd].local_port = port_range_alloc_port(s->sport_range);
if (!fdinfo[fd].local_port)
break;
fdinfo[fd].port_range = s->sport_range;
set_host_port(&src, fdinfo[fd].local_port);
ret = tcp_bind_socket(fd, flags, &src, remote);
} while (ret != 0); /* binding NOK */
}
else {
ret = tcp_bind_socket(fd, flags, &s->source_addr, remote);
}
if (ret) {
set_server_check_status(s, HCHK_STATUS_SOCKERR, NULL);
switch (ret) {
case 1:
Alert("Cannot bind to source address before connect() for server %s/%s. Aborting.\n",
s->proxy->id, s->id);
break;
case 2:
Alert("Cannot bind to tproxy source address before connect() for server %s/%s. Aborting.\n",
s->proxy->id, s->id);
break;
}
}
}
else if (s->proxy->options & PR_O_BIND_SRC) {
struct sockaddr_storage *remote = NULL;
int ret, flags = 0;
#if defined(CONFIG_HAP_CTTPROXY) || defined(CONFIG_HAP_LINUX_TPROXY)
if ((s->proxy->options & PR_O_TPXY_MASK) == PR_O_TPXY_ADDR) {
remote = &s->proxy->tproxy_addr;
flags = 3;
}
#endif
#ifdef SO_BINDTODEVICE
/* Note: this might fail if not CAP_NET_RAW */
if (s->proxy->iface_name)
setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
s->proxy->iface_name, s->proxy->iface_len + 1);
#endif
ret = tcp_bind_socket(fd, flags, &s->proxy->source_addr, remote);
if (ret) {
set_server_check_status(s, HCHK_STATUS_SOCKERR, NULL);
switch (ret) {
case 1:
Alert("Cannot bind to source address before connect() for %s '%s'. Aborting.\n",
proxy_type_str(s->proxy), s->proxy->id);
break;
case 2:
Alert("Cannot bind to tproxy source address before connect() for %s '%s'. Aborting.\n",
proxy_type_str(s->proxy), s->proxy->id);
break;
}
}
}
if (s->result == SRV_CHK_UNKNOWN) {
#if defined(TCP_QUICKACK)
/* disabling tcp quick ack now allows
* the request to leave the machine with
* the first ACK.
*/
if (s->proxy->options2 & PR_O2_SMARTCON)
setsockopt(fd, IPPROTO_TCP, TCP_QUICKACK, (char *) &zero, sizeof(zero));
#endif
if ((connect(fd, (struct sockaddr *)&sa, get_addr_len(&sa)) != -1) || (errno == EINPROGRESS)) {
/* OK, connection in progress or established */
//fprintf(stderr, "process_chk: 4\n");
s->curfd = fd; /* that's how we know a test is in progress ;-) */
s->check_conn->flags = CO_FL_WAIT_L4_CONN; /* TCP connection pending */
fd_insert(fd);
fdtab[fd].owner = t;
fdtab[fd].iocb = &check_iocb;
fdtab[fd].flags = FD_FL_TCP | FD_FL_TCP_NODELAY;
fd_want_send(fd); /* for connect status */
#ifdef DEBUG_FULL
assert (!EV_FD_ISSET(fd, DIR_RD));
#endif
//fprintf(stderr, "process_chk: 4+, %lu\n", __tv_to_ms(&s->proxy->timeout.connect));
/* we allow up to min(inter, timeout.connect) for a connection
* to establish but only when timeout.check is set
* as it may be to short for a full check otherwise
*/
t->expire = tick_add(now_ms, MS_TO_TICKS(s->inter));
if (s->proxy->timeout.check && s->proxy->timeout.connect) {
int t_con = tick_add(now_ms, s->proxy->timeout.connect);
t->expire = tick_first(t->expire, t_con);
}
return t;
}
else if (errno != EALREADY && errno != EISCONN && errno != EAGAIN) {
/* a real error */
switch (errno) {
/* FIXME: is it possible to get ECONNREFUSED/ENETUNREACH with O_NONBLOCK? */
case ECONNREFUSED:
case ENETUNREACH:
set_server_check_status(s, HCHK_STATUS_L4CON, strerror(errno));
break;
default:
set_server_check_status(s, HCHK_STATUS_SOCKERR, strerror(errno));
}
}
}
}
port_range_release_port(fdinfo[fd].port_range, fdinfo[fd].local_port);
fdinfo[fd].port_range = NULL;
close(fd); /* socket creation error */
}
else
set_server_check_status(s, HCHK_STATUS_SOCKERR, strerror(errno));
if (s->result == SRV_CHK_UNKNOWN) { /* nothing done */
//fprintf(stderr, "process_chk: 6\n");
while (tick_is_expired(t->expire, now_ms))
t->expire = tick_add(t->expire, MS_TO_TICKS(s->inter));
goto new_chk; /* may be we should initialize a new check */
}
/* here, we have seen a failure */
if (s->health > s->rise) {
s->health--; /* still good */
s->counters.failed_checks++;
}
else
set_server_down(s);
//fprintf(stderr, "process_chk: 7, %lu\n", __tv_to_ms(&s->proxy->timeout.connect));
/* we allow up to min(inter, timeout.connect) for a connection
* to establish but only when timeout.check is set
* as it may be to short for a full check otherwise
*/
while (tick_is_expired(t->expire, now_ms)) {
int t_con;
t_con = tick_add(t->expire, s->proxy->timeout.connect);
t->expire = tick_add(t->expire, MS_TO_TICKS(s->inter));
if (s->proxy->timeout.check)
t->expire = tick_first(t->expire, t_con);
}
goto new_chk;
}
else {
/* there was a test running */
if ((s->result & (SRV_CHK_ERROR|SRV_CHK_RUNNING)) == SRV_CHK_RUNNING) { /* good server detected */
/* we may have to add/remove this server from the LB group */
if ((s->state & SRV_RUNNING) && (s->proxy->options & PR_O_DISABLE404)) {
if ((s->state & SRV_GOINGDOWN) &&
((s->result & (SRV_CHK_RUNNING|SRV_CHK_DISABLE)) == SRV_CHK_RUNNING))
set_server_enabled(s);
else if (!(s->state & SRV_GOINGDOWN) &&
((s->result & (SRV_CHK_RUNNING | SRV_CHK_DISABLE)) ==
(SRV_CHK_RUNNING | SRV_CHK_DISABLE)))
set_server_disabled(s);
}
if (s->health < s->rise + s->fall - 1) {
s->health++; /* was bad, stays for a while */
set_server_up(s);
}
s->curfd = -1; /* no check running anymore */
fd_delete(fd);
rv = 0;
if (global.spread_checks > 0) {
rv = srv_getinter(s) * global.spread_checks / 100;
rv -= (int) (2 * rv * (rand() / (RAND_MAX + 1.0)));
}
t->expire = tick_add(now_ms, MS_TO_TICKS(srv_getinter(s) + rv));
goto new_chk;
}
else if ((s->result & SRV_CHK_ERROR) || tick_is_expired(t->expire, now_ms)) {
if (!(s->result & SRV_CHK_ERROR)) {
if (!EV_FD_ISSET(fd, DIR_RD)) {
set_server_check_status(s, HCHK_STATUS_L4TOUT, NULL);
} else {
if ((s->proxy->options2 & PR_O2_CHK_ANY) == PR_O2_SSL3_CHK)
set_server_check_status(s, HCHK_STATUS_L6TOUT, NULL);
else /* HTTP, SMTP */
set_server_check_status(s, HCHK_STATUS_L7TOUT, NULL);
}
}
/* failure or timeout detected */
if (s->health > s->rise) {
s->health--; /* still good */
s->counters.failed_checks++;
}
else
set_server_down(s);
s->curfd = -1;
fd_delete(fd);
rv = 0;
if (global.spread_checks > 0) {
rv = srv_getinter(s) * global.spread_checks / 100;
rv -= (int) (2 * rv * (rand() / (RAND_MAX + 1.0)));
}
t->expire = tick_add(now_ms, MS_TO_TICKS(srv_getinter(s) + rv));
goto new_chk;
}
/* if result is unknown and there's no timeout, we have to wait again */
}
s->result = SRV_CHK_UNKNOWN;
return t;
}
/*
* Start health-check.
* Returns 0 if OK, -1 if error, and prints the error in this case.
*/
int start_checks() {
struct proxy *px;
struct server *s;
struct task *t;
int nbchk=0, mininter=0, srvpos=0;
/* 1- count the checkers to run simultaneously.
* We also determine the minimum interval among all of those which
* have an interval larger than SRV_CHK_INTER_THRES. This interval
* will be used to spread their start-up date. Those which have
* a shorter interval will start independently and will not dictate
* too short an interval for all others.
*/
for (px = proxy; px; px = px->next) {
for (s = px->srv; s; s = s->next) {
if (!(s->state & SRV_CHECKED))
continue;
if ((srv_getinter(s) >= SRV_CHK_INTER_THRES) &&
(!mininter || mininter > srv_getinter(s)))
mininter = srv_getinter(s);
nbchk++;
}
}
if (!nbchk)
return 0;
srand((unsigned)time(NULL));
/*
* 2- start them as far as possible from each others. For this, we will
* start them after their interval set to the min interval divided by
* the number of servers, weighted by the server's position in the list.
*/
for (px = proxy; px; px = px->next) {
for (s = px->srv; s; s = s->next) {
if (s->slowstart) {
if ((t = task_new()) == NULL) {
Alert("Starting [%s:%s] check: out of memory.\n", px->id, s->id);
return -1;
}
/* We need a warmup task that will be called when the server
* state switches from down to up.
*/
s->warmup = t;
t->process = server_warmup;
t->context = s;
t->expire = TICK_ETERNITY;
}
if (!(s->state & SRV_CHECKED))
continue;
/* one task for the checks */
if ((t = task_new()) == NULL) {
Alert("Starting [%s:%s] check: out of memory.\n", px->id, s->id);
return -1;
}
s->check = t;
t->process = process_chk;
t->context = s;
/* check this every ms */
t->expire = tick_add(now_ms,
MS_TO_TICKS(((mininter && mininter >= srv_getinter(s)) ?
mininter : srv_getinter(s)) * srvpos / nbchk));
s->check_start = now;
task_queue(t);
srvpos++;
}
}
return 0;
}
/*
* Perform content verification check on data in s->check_data buffer.
* The buffer MUST be terminated by a null byte before calling this function.
* Sets server status appropriately. The caller is responsible for ensuring
* that the buffer contains at least 13 characters. If <done> is zero, we may
* return 0 to indicate that data is required to decide of a match.
*/
static int httpchk_expect(struct server *s, int done)
{
static char status_msg[] = "HTTP status check returned code <000>";
char status_code[] = "000";
char *contentptr;
int crlf;
int ret;
switch (s->proxy->options2 & PR_O2_EXP_TYPE) {
case PR_O2_EXP_STS:
case PR_O2_EXP_RSTS:
memcpy(status_code, s->check_data + 9, 3);
memcpy(status_msg + strlen(status_msg) - 4, s->check_data + 9, 3);
if ((s->proxy->options2 & PR_O2_EXP_TYPE) == PR_O2_EXP_STS)
ret = strncmp(s->proxy->expect_str, status_code, 3) == 0;
else
ret = regexec(s->proxy->expect_regex, status_code, MAX_MATCH, pmatch, 0) == 0;
/* we necessarily have the response, so there are no partial failures */
if (s->proxy->options2 & PR_O2_EXP_INV)
ret = !ret;
set_server_check_status(s, ret ? HCHK_STATUS_L7OKD : HCHK_STATUS_L7STS, status_msg);
break;
case PR_O2_EXP_STR:
case PR_O2_EXP_RSTR:
/* very simple response parser: ignore CR and only count consecutive LFs,
* stop with contentptr pointing to first char after the double CRLF or
* to '\0' if crlf < 2.
*/
crlf = 0;
for (contentptr = s->check_data; *contentptr; contentptr++) {
if (crlf >= 2)
break;
if (*contentptr == '\r')
continue;
else if (*contentptr == '\n')
crlf++;
else
crlf = 0;
}
/* Check that response contains a body... */
if (crlf < 2) {
if (!done)
return 0;
set_server_check_status(s, HCHK_STATUS_L7RSP,
"HTTP content check could not find a response body");
return 1;
}
/* Check that response body is not empty... */
if (*contentptr == '\0') {
if (!done)
return 0;
set_server_check_status(s, HCHK_STATUS_L7RSP,
"HTTP content check found empty response body");
return 1;
}
/* Check the response content against the supplied string
* or regex... */
if ((s->proxy->options2 & PR_O2_EXP_TYPE) == PR_O2_EXP_STR)
ret = strstr(contentptr, s->proxy->expect_str) != NULL;
else
ret = regexec(s->proxy->expect_regex, contentptr, MAX_MATCH, pmatch, 0) == 0;
/* if we don't match, we may need to wait more */
if (!ret && !done)
return 0;
if (ret) {
/* content matched */
if (s->proxy->options2 & PR_O2_EXP_INV)
set_server_check_status(s, HCHK_STATUS_L7RSP,
"HTTP check matched unwanted content");
else
set_server_check_status(s, HCHK_STATUS_L7OKD,
"HTTP content check matched");
}
else {
if (s->proxy->options2 & PR_O2_EXP_INV)
set_server_check_status(s, HCHK_STATUS_L7OKD,
"HTTP check did not match unwanted content");
else
set_server_check_status(s, HCHK_STATUS_L7RSP,
"HTTP content check did not match");
}
break;
}
return 1;
}
/*
* Local variables:
* c-indent-level: 8
* c-basic-offset: 8
* End:
*/