Mercurial > hg > nginx-quic
view src/core/ngx_syslog.c @ 6133:af7eba90645d
Win32: shared memory base addresses and remapping.
Two mechanisms are implemented to make it possible to store pointers
in shared memory on Windows, in particular on Windows Vista and later
versions with ASLR:
- The ngx_shm_remap() function added to allow remapping of a shared memory
zone to the address originally used for it in the master process. While
important, it doesn't solve the problem by itself as in many cases it's
not possible to use the address because of conflicts with other
allocations.
- We now create mappings at the same address in all processes by starting
mappings at predefined addresses normally unused by newborn processes.
These two mechanisms combined allow to use shared memory on Windows
almost without problems, including reloads.
Based on the patch by Sergey Brester:
http://mailman.nginx.org/pipermail/nginx-devel/2015-April/006836.html
author | Maxim Dounin <mdounin@mdounin.ru> |
---|---|
date | Mon, 27 Apr 2015 18:25:42 +0300 |
parents | 68f64bc17fa4 |
children | a6a2016b8e31 |
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/* * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #define NGX_SYSLOG_MAX_STR \ NGX_MAX_ERROR_STR + sizeof("<255>Jan 01 00:00:00 ") - 1 \ + (NGX_MAXHOSTNAMELEN - 1) + 1 /* space */ \ + 32 /* tag */ + 2 /* colon, space */ static char *ngx_syslog_parse_args(ngx_conf_t *cf, ngx_syslog_peer_t *peer); static ngx_int_t ngx_syslog_init_peer(ngx_syslog_peer_t *peer); static void ngx_syslog_cleanup(void *data); static char *facilities[] = { "kern", "user", "mail", "daemon", "auth", "intern", "lpr", "news", "uucp", "clock", "authpriv", "ftp", "ntp", "audit", "alert", "cron", "local0", "local1", "local2", "local3", "local4", "local5", "local6", "local7", NULL }; /* note 'error/warn' like in nginx.conf, not 'err/warning' */ static char *severities[] = { "emerg", "alert", "crit", "error", "warn", "notice", "info", "debug", NULL }; static ngx_log_t ngx_syslog_dummy_log; static ngx_event_t ngx_syslog_dummy_event; char * ngx_syslog_process_conf(ngx_conf_t *cf, ngx_syslog_peer_t *peer) { peer->pool = cf->pool; peer->facility = NGX_CONF_UNSET_UINT; peer->severity = NGX_CONF_UNSET_UINT; if (ngx_syslog_parse_args(cf, peer) != NGX_CONF_OK) { return NGX_CONF_ERROR; } if (peer->server.sockaddr == NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "no syslog server specified"); return NGX_CONF_ERROR; } if (peer->facility == NGX_CONF_UNSET_UINT) { peer->facility = 23; /* local7 */ } if (peer->severity == NGX_CONF_UNSET_UINT) { peer->severity = 6; /* info */ } if (peer->tag.data == NULL) { ngx_str_set(&peer->tag, "nginx"); } peer->conn.fd = (ngx_socket_t) -1; return NGX_CONF_OK; } static char * ngx_syslog_parse_args(ngx_conf_t *cf, ngx_syslog_peer_t *peer) { u_char *p, *comma, c; size_t len; ngx_str_t *value; ngx_url_t u; ngx_uint_t i; value = cf->args->elts; p = value[1].data + sizeof("syslog:") - 1; for ( ;; ) { comma = (u_char *) ngx_strchr(p, ','); if (comma != NULL) { len = comma - p; *comma = '\0'; } else { len = value[1].data + value[1].len - p; } if (ngx_strncmp(p, "server=", 7) == 0) { if (peer->server.sockaddr != NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"server\""); return NGX_CONF_ERROR; } ngx_memzero(&u, sizeof(ngx_url_t)); u.url.data = p + 7; u.url.len = len - 7; u.default_port = 514; if (ngx_parse_url(cf->pool, &u) != NGX_OK) { if (u.err) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%s in syslog server \"%V\"", u.err, &u.url); } return NGX_CONF_ERROR; } peer->server = u.addrs[0]; } else if (ngx_strncmp(p, "facility=", 9) == 0) { if (peer->facility != NGX_CONF_UNSET_UINT) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"facility\""); return NGX_CONF_ERROR; } for (i = 0; facilities[i] != NULL; i++) { if (ngx_strcmp(p + 9, facilities[i]) == 0) { peer->facility = i; goto next; } } ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unknown syslog facility \"%s\"", p + 9); return NGX_CONF_ERROR; } else if (ngx_strncmp(p, "severity=", 9) == 0) { if (peer->severity != NGX_CONF_UNSET_UINT) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"severity\""); return NGX_CONF_ERROR; } for (i = 0; severities[i] != NULL; i++) { if (ngx_strcmp(p + 9, severities[i]) == 0) { peer->severity = i; goto next; } } ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unknown syslog severity \"%s\"", p + 9); return NGX_CONF_ERROR; } else if (ngx_strncmp(p, "tag=", 4) == 0) { if (peer->tag.data != NULL) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "duplicate syslog \"tag\""); return NGX_CONF_ERROR; } /* * RFC 3164: the TAG is a string of ABNF alphanumeric characters * that MUST NOT exceed 32 characters. */ if (len - 4 > 32) { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "syslog tag length exceeds 32"); return NGX_CONF_ERROR; } for (i = 4; i < len; i++) { c = ngx_tolower(p[i]); if (c < '0' || (c > '9' && c < 'a' && c != '_') || c > 'z') { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "syslog \"tag\" only allows " "alphanumeric characters " "and underscore"); return NGX_CONF_ERROR; } } peer->tag.data = p + 4; peer->tag.len = len - 4; } else { ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "unknown syslog parameter \"%s\"", p); return NGX_CONF_ERROR; } next: if (comma == NULL) { break; } p = comma + 1; } return NGX_CONF_OK; } u_char * ngx_syslog_add_header(ngx_syslog_peer_t *peer, u_char *buf) { ngx_uint_t pri; pri = peer->facility * 8 + peer->severity; return ngx_sprintf(buf, "<%ui>%V %V %V: ", pri, &ngx_cached_syslog_time, &ngx_cycle->hostname, &peer->tag); } void ngx_syslog_writer(ngx_log_t *log, ngx_uint_t level, u_char *buf, size_t len) { u_char *p, msg[NGX_SYSLOG_MAX_STR]; ngx_uint_t head_len; ngx_syslog_peer_t *peer; peer = log->wdata; if (peer->busy) { return; } peer->busy = 1; peer->severity = level - 1; p = ngx_syslog_add_header(peer, msg); head_len = p - msg; len -= NGX_LINEFEED_SIZE; if (len > NGX_SYSLOG_MAX_STR - head_len) { len = NGX_SYSLOG_MAX_STR - head_len; } p = ngx_snprintf(p, len, "%s", buf); (void) ngx_syslog_send(peer, msg, p - msg); peer->busy = 0; } ssize_t ngx_syslog_send(ngx_syslog_peer_t *peer, u_char *buf, size_t len) { ssize_t n; if (peer->conn.fd == (ngx_socket_t) -1) { if (ngx_syslog_init_peer(peer) != NGX_OK) { return NGX_ERROR; } } /* log syslog socket events with valid log */ peer->conn.log = ngx_cycle->log; if (ngx_send) { n = ngx_send(&peer->conn, buf, len); } else { /* event module has not yet set ngx_io */ n = ngx_os_io.send(&peer->conn, buf, len); } #if (NGX_HAVE_UNIX_DOMAIN) if (n == NGX_ERROR && peer->server.sockaddr->sa_family == AF_UNIX) { if (ngx_close_socket(peer->conn.fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_close_socket_n " failed"); } peer->conn.fd = (ngx_socket_t) -1; } #endif return n; } static ngx_int_t ngx_syslog_init_peer(ngx_syslog_peer_t *peer) { ngx_socket_t fd; ngx_pool_cleanup_t *cln; peer->conn.read = &ngx_syslog_dummy_event; peer->conn.write = &ngx_syslog_dummy_event; ngx_syslog_dummy_event.log = &ngx_syslog_dummy_log; fd = ngx_socket(peer->server.sockaddr->sa_family, SOCK_DGRAM, 0); if (fd == (ngx_socket_t) -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_socket_n " failed"); return NGX_ERROR; } if (ngx_nonblocking(fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_nonblocking_n " failed"); goto failed; } if (connect(fd, peer->server.sockaddr, peer->server.socklen) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, "connect() failed"); goto failed; } cln = ngx_pool_cleanup_add(peer->pool, 0); if (cln == NULL) { goto failed; } cln->data = peer; cln->handler = ngx_syslog_cleanup; peer->conn.fd = fd; /* UDP sockets are always ready to write */ peer->conn.write->ready = 1; return NGX_OK; failed: if (ngx_close_socket(fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_close_socket_n " failed"); } return NGX_ERROR; } static void ngx_syslog_cleanup(void *data) { ngx_syslog_peer_t *peer = data; /* prevents further use of this peer */ peer->busy = 1; if (peer->conn.fd == (ngx_socket_t) -1) { return; } if (ngx_close_socket(peer->conn.fd) == -1) { ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno, ngx_close_socket_n " failed"); } }