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|
/*++
/* NAME
/* postscreen 8
/* SUMMARY
/* Postfix zombie blocker
/* SYNOPSIS
/* \fBpostscreen\fR [generic Postfix daemon options]
/* DESCRIPTION
/* The Postfix \fBpostscreen\fR(8) server provides additional
/* protection against mail server overload. One \fBpostscreen\fR(8)
/* process handles multiple inbound SMTP connections, and decides
/* which clients may talk to a Postfix SMTP server process.
/* By keeping spambots away, \fBpostscreen\fR(8) leaves more
/* SMTP server processes available for legitimate clients, and
/* delays the onset of server overload conditions.
/*
/* This program should not be used on SMTP ports that receive
/* mail from end-user clients (MUAs). In a typical deployment,
/* \fBpostscreen\fR(8) handles the MX service on TCP port 25, and
/* \fBsmtpd\fR(8) receives mail from MUAs on the \fBsubmission\fR
/* service (TCP port 587) which requires client authentication.
/* Alternatively, a site could set up a dedicated, non-postscreen,
/* "port 25" server that provides \fBsubmission\fR service and
/* client authentication, but no MX service.
/*
/* \fBpostscreen\fR(8) maintains a temporary allowlist for
/* clients that have passed a number of tests. When an SMTP
/* client IP address is allowlisted, \fBpostscreen\fR(8) hands
/* off the connection immediately to a Postfix SMTP server
/* process. This minimizes the overhead for legitimate mail.
/*
/* By default, \fBpostscreen\fR(8) logs statistics and hands
/* off each connection to a Postfix SMTP server process, while
/* excluding clients in mynetworks from all tests (primarily,
/* to avoid problems with non-standard SMTP implementations
/* in network appliances). This default mode blocks no clients,
/* and is useful for non-destructive testing.
/*
/* In a typical production setting, \fBpostscreen\fR(8) is
/* configured to reject mail from clients that fail one or
/* more tests. \fBpostscreen\fR(8) logs rejected mail with the
/* client address, helo, sender and recipient information.
/*
/* \fBpostscreen\fR(8) is not an SMTP proxy; this is intentional.
/* The purpose is to keep spambots away from Postfix SMTP
/* server processes, while minimizing overhead for legitimate
/* traffic.
/* SECURITY
/* .ad
/* .fi
/* The \fBpostscreen\fR(8) server is moderately security-sensitive.
/* It talks to untrusted clients on the network. The process
/* can be run chrooted at fixed low privilege.
/* STANDARDS
/* RFC 821 (SMTP protocol)
/* RFC 1123 (Host requirements)
/* RFC 1652 (8bit-MIME transport)
/* RFC 1869 (SMTP service extensions)
/* RFC 1870 (Message Size Declaration)
/* RFC 1985 (ETRN command)
/* RFC 2034 (SMTP Enhanced Status Codes)
/* RFC 2821 (SMTP protocol)
/* Not: RFC 2920 (SMTP Pipelining)
/* RFC 3030 (CHUNKING without BINARYMIME)
/* RFC 3207 (STARTTLS command)
/* RFC 3461 (SMTP DSN Extension)
/* RFC 3463 (Enhanced Status Codes)
/* RFC 5321 (SMTP protocol, including multi-line 220 banners)
/* DIAGNOSTICS
/* Problems and transactions are logged to \fBsyslogd\fR(8)
/* or \fBpostlogd\fR(8).
/* BUGS
/* The \fBpostscreen\fR(8) built-in SMTP protocol engine
/* currently does not announce support for AUTH, XCLIENT or
/* XFORWARD.
/* If you need to make these services available
/* on port 25, then do not enable the optional "after 220
/* server greeting" tests.
/*
/* The optional "after 220 server greeting" tests may result in
/* unexpected delivery delays from senders that retry email delivery
/* from a different IP address. Reason: after passing these tests a
/* new client must disconnect, and reconnect from the same IP
/* address before it can deliver mail. See POSTSCREEN_README, section
/* "Tests after the 220 SMTP server greeting", for a discussion.
/* CONFIGURATION PARAMETERS
/* .ad
/* .fi
/* Changes to main.cf are not picked up automatically, as
/* \fBpostscreen\fR(8) processes may run for several hours.
/* Use the command "postfix reload" after a configuration
/* change.
/*
/* The text below provides only a parameter summary. See
/* \fBpostconf\fR(5) for more details including examples.
/*
/* NOTE: Some \fBpostscreen\fR(8) parameters implement
/* stress-dependent behavior. This is supported only when the
/* default parameter value is stress-dependent (that is, it
/* looks like ${stress?{X}:{Y}}, or it is the $\fIname\fR
/* of an smtpd parameter with a stress-dependent default).
/* Other parameters always evaluate as if the \fBstress\fR
/* parameter value is the empty string.
/* COMPATIBILITY CONTROLS
/* .ad
/* .fi
/* .IP "\fBpostscreen_command_filter ($smtpd_command_filter)\fR"
/* A mechanism to transform commands from remote SMTP clients.
/* .IP "\fBpostscreen_discard_ehlo_keyword_address_maps ($smtpd_discard_ehlo_keyword_address_maps)\fR"
/* Lookup tables, indexed by the remote SMTP client address, with
/* case insensitive lists of EHLO keywords (pipelining, starttls, auth,
/* etc.) that the \fBpostscreen\fR(8) server will not send in the EHLO response
/* to a remote SMTP client.
/* .IP "\fBpostscreen_discard_ehlo_keywords ($smtpd_discard_ehlo_keywords)\fR"
/* A case insensitive list of EHLO keywords (pipelining, starttls,
/* auth, etc.) that the \fBpostscreen\fR(8) server will not send in the EHLO
/* response to a remote SMTP client.
/* .PP
/* Available in Postfix version 3.1 and later:
/* .IP "\fBdns_ncache_ttl_fix_enable (no)\fR"
/* Enable a workaround for future libc incompatibility.
/* .PP
/* Available in Postfix version 3.4 and later:
/* .IP "\fBpostscreen_reject_footer_maps ($smtpd_reject_footer_maps)\fR"
/* Optional lookup table for information that is appended after a 4XX
/* or 5XX \fBpostscreen\fR(8) server response.
/* .PP
/* Available in Postfix 3.6 and later:
/* .IP "\fBrespectful_logging (see 'postconf -d' output)\fR"
/* Avoid logging that implies white is better than black.
/* TROUBLE SHOOTING CONTROLS
/* .ad
/* .fi
/* .IP "\fBpostscreen_expansion_filter (see 'postconf -d' output)\fR"
/* List of characters that are permitted in postscreen_reject_footer
/* attribute expansions.
/* .IP "\fBpostscreen_reject_footer ($smtpd_reject_footer)\fR"
/* Optional information that is appended after a 4XX or 5XX
/* \fBpostscreen\fR(8) server
/* response.
/* .IP "\fBsoft_bounce (no)\fR"
/* Safety net to keep mail queued that would otherwise be returned to
/* the sender.
/* BEFORE-POSTSCREEN PROXY AGENT
/* .ad
/* .fi
/* Available in Postfix version 2.10 and later:
/* .IP "\fBpostscreen_upstream_proxy_protocol (empty)\fR"
/* The name of the proxy protocol used by an optional before-postscreen
/* proxy agent.
/* .IP "\fBpostscreen_upstream_proxy_timeout (5s)\fR"
/* The time limit for the proxy protocol specified with the
/* postscreen_upstream_proxy_protocol parameter.
/* PERMANENT ALLOW/DENYLIST TEST
/* .ad
/* .fi
/* This test is executed immediately after a remote SMTP client
/* connects. If a client is permanently allowlisted, the client
/* will be handed off immediately to a Postfix SMTP server
/* process.
/* .IP "\fBpostscreen_access_list (permit_mynetworks)\fR"
/* Permanent allow/denylist for remote SMTP client IP addresses.
/* .IP "\fBpostscreen_blacklist_action (ignore)\fR"
/* Renamed to postscreen_denylist_action in Postfix 3.6.
/* MAIL EXCHANGER POLICY TESTS
/* .ad
/* .fi
/* When \fBpostscreen\fR(8) is configured to monitor all primary
/* and backup MX addresses, it can refuse to allowlist clients
/* that connect to a backup MX address only. For small sites,
/* this requires configuring primary and backup MX addresses
/* on the same MTA. Larger sites would have to share the
/* \fBpostscreen\fR(8) cache between primary and backup MTAs,
/* which would introduce a common point of failure.
/* .IP "\fBpostscreen_allowlist_interfaces (static:all)\fR"
/* A list of local \fBpostscreen\fR(8) server IP addresses where a
/* non-allowlisted remote SMTP client can obtain \fBpostscreen\fR(8)'s temporary
/* allowlist status.
/* BEFORE 220 GREETING TESTS
/* .ad
/* .fi
/* These tests are executed before the remote SMTP client
/* receives the "220 servername" greeting. If no tests remain
/* after the successful completion of this phase, the client
/* will be handed off immediately to a Postfix SMTP server
/* process.
/* .IP "\fBdnsblog_service_name (dnsblog)\fR"
/* The name of the \fBdnsblog\fR(8) service entry in master.cf.
/* .IP "\fBpostscreen_dnsbl_action (ignore)\fR"
/* The action that \fBpostscreen\fR(8) takes when a remote SMTP client's combined
/* DNSBL score is equal to or greater than a threshold (as defined
/* with the postscreen_dnsbl_sites and postscreen_dnsbl_threshold
/* parameters).
/* .IP "\fBpostscreen_dnsbl_reply_map (empty)\fR"
/* A mapping from an actual DNSBL domain name which includes a secret
/* password, to the DNSBL domain name that postscreen will reply with
/* when it rejects mail.
/* .IP "\fBpostscreen_dnsbl_sites (empty)\fR"
/* Optional list of patterns with DNS allow/denylist domains, filters
/* and weight
/* factors.
/* .IP "\fBpostscreen_dnsbl_threshold (1)\fR"
/* The inclusive lower bound for blocking a remote SMTP client, based on
/* its combined DNSBL score as defined with the postscreen_dnsbl_sites
/* parameter.
/* .IP "\fBpostscreen_greet_action (ignore)\fR"
/* The action that \fBpostscreen\fR(8) takes when a remote SMTP client speaks
/* before its turn within the time specified with the postscreen_greet_wait
/* parameter.
/* .IP "\fBpostscreen_greet_banner ($smtpd_banner)\fR"
/* The \fItext\fR in the optional "220-\fItext\fR..." server
/* response that
/* \fBpostscreen\fR(8) sends ahead of the real Postfix SMTP server's "220
/* text..." response, in an attempt to confuse bad SMTP clients so
/* that they speak before their turn (pre-greet).
/* .IP "\fBpostscreen_greet_wait (normal: 6s, overload: 2s)\fR"
/* The amount of time that \fBpostscreen\fR(8) will wait for an SMTP
/* client to send a command before its turn, and for DNS blocklist
/* lookup results to arrive (default: up to 2 seconds under stress,
/* up to 6 seconds otherwise).
/* .IP "\fBsmtpd_service_name (smtpd)\fR"
/* The internal service that \fBpostscreen\fR(8) hands off allowed
/* connections to.
/* .PP
/* Available in Postfix version 2.11 and later:
/* .IP "\fBpostscreen_dnsbl_whitelist_threshold (0)\fR"
/* Renamed to postscreen_dnsbl_allowlist_threshold in Postfix 3.6.
/* .PP
/* Available in Postfix version 3.0 and later:
/* .IP "\fBpostscreen_dnsbl_timeout (10s)\fR"
/* The time limit for DNSBL or DNSWL lookups.
/* .PP
/* Available in Postfix version 3.6 and later:
/* .IP "\fBpostscreen_denylist_action (ignore)\fR"
/* The action that \fBpostscreen\fR(8) takes when a remote SMTP client is
/* permanently denylisted with the postscreen_access_list parameter.
/* .IP "\fBpostscreen_allowlist_interfaces (static:all)\fR"
/* A list of local \fBpostscreen\fR(8) server IP addresses where a
/* non-allowlisted remote SMTP client can obtain \fBpostscreen\fR(8)'s temporary
/* allowlist status.
/* .IP "\fBpostscreen_dnsbl_allowlist_threshold (0)\fR"
/* Allow a remote SMTP client to skip "before" and "after 220
/* greeting" protocol tests, based on its combined DNSBL score as
/* defined with the postscreen_dnsbl_sites parameter.
/* AFTER 220 GREETING TESTS
/* .ad
/* .fi
/* These tests are executed after the remote SMTP client
/* receives the "220 servername" greeting. If a client passes
/* all tests during this phase, it will receive a 4XX response
/* to all RCPT TO commands. After the client reconnects, it
/* will be allowed to talk directly to a Postfix SMTP server
/* process.
/* .IP "\fBpostscreen_bare_newline_action (ignore)\fR"
/* The action that \fBpostscreen\fR(8) takes when a remote SMTP client sends
/* a bare newline character, that is, a newline not preceded by carriage
/* return.
/* .IP "\fBpostscreen_bare_newline_enable (no)\fR"
/* Enable "bare newline" SMTP protocol tests in the \fBpostscreen\fR(8)
/* server.
/* .IP "\fBpostscreen_disable_vrfy_command ($disable_vrfy_command)\fR"
/* Disable the SMTP VRFY command in the \fBpostscreen\fR(8) daemon.
/* .IP "\fBpostscreen_forbidden_commands ($smtpd_forbidden_commands)\fR"
/* List of commands that the \fBpostscreen\fR(8) server considers in
/* violation of the SMTP protocol.
/* .IP "\fBpostscreen_helo_required ($smtpd_helo_required)\fR"
/* Require that a remote SMTP client sends HELO or EHLO before
/* commencing a MAIL transaction.
/* .IP "\fBpostscreen_non_smtp_command_action (drop)\fR"
/* The action that \fBpostscreen\fR(8) takes when a remote SMTP client sends
/* non-SMTP commands as specified with the postscreen_forbidden_commands
/* parameter.
/* .IP "\fBpostscreen_non_smtp_command_enable (no)\fR"
/* Enable "non-SMTP command" tests in the \fBpostscreen\fR(8) server.
/* .IP "\fBpostscreen_pipelining_action (enforce)\fR"
/* The action that \fBpostscreen\fR(8) takes when a remote SMTP client
/* sends
/* multiple commands instead of sending one command and waiting for
/* the server to respond.
/* .IP "\fBpostscreen_pipelining_enable (no)\fR"
/* Enable "pipelining" SMTP protocol tests in the \fBpostscreen\fR(8)
/* server.
/* CACHE CONTROLS
/* .ad
/* .fi
/* .IP "\fBpostscreen_cache_cleanup_interval (12h)\fR"
/* The amount of time between \fBpostscreen\fR(8) cache cleanup runs.
/* .IP "\fBpostscreen_cache_map (btree:$data_directory/postscreen_cache)\fR"
/* Persistent storage for the \fBpostscreen\fR(8) server decisions.
/* .IP "\fBpostscreen_cache_retention_time (7d)\fR"
/* The amount of time that \fBpostscreen\fR(8) will cache an expired
/* temporary allowlist entry before it is removed.
/* .IP "\fBpostscreen_bare_newline_ttl (30d)\fR"
/* The amount of time that \fBpostscreen\fR(8) will use the result from
/* a successful "bare newline" SMTP protocol test.
/* .IP "\fBpostscreen_dnsbl_max_ttl (${postscreen_dnsbl_ttl?{$postscreen_dnsbl_ttl}:{1}}h)\fR"
/* The maximum amount of time that \fBpostscreen\fR(8) will use the
/* result from a successful DNS-based reputation test before a
/* client IP address is required to pass that test again.
/* .IP "\fBpostscreen_dnsbl_min_ttl (60s)\fR"
/* The minimum amount of time that \fBpostscreen\fR(8) will use the
/* result from a successful DNS-based reputation test before a
/* client IP address is required to pass that test again.
/* .IP "\fBpostscreen_greet_ttl (1d)\fR"
/* The amount of time that \fBpostscreen\fR(8) will use the result from
/* a successful PREGREET test.
/* .IP "\fBpostscreen_non_smtp_command_ttl (30d)\fR"
/* The amount of time that \fBpostscreen\fR(8) will use the result from
/* a successful "non_smtp_command" SMTP protocol test.
/* .IP "\fBpostscreen_pipelining_ttl (30d)\fR"
/* The amount of time that \fBpostscreen\fR(8) will use the result from
/* a successful "pipelining" SMTP protocol test.
/* RESOURCE CONTROLS
/* .ad
/* .fi
/* .IP "\fBline_length_limit (2048)\fR"
/* Upon input, long lines are chopped up into pieces of at most
/* this length; upon delivery, long lines are reconstructed.
/* .IP "\fBpostscreen_client_connection_count_limit ($smtpd_client_connection_count_limit)\fR"
/* How many simultaneous connections any remote SMTP client is
/* allowed to have
/* with the \fBpostscreen\fR(8) daemon.
/* .IP "\fBpostscreen_command_count_limit (20)\fR"
/* The limit on the total number of commands per SMTP session for
/* \fBpostscreen\fR(8)'s built-in SMTP protocol engine.
/* .IP "\fBpostscreen_command_time_limit (normal: 300s, overload: 10s)\fR"
/* The time limit to read an entire command line with \fBpostscreen\fR(8)'s
/* built-in SMTP protocol engine.
/* .IP "\fBpostscreen_post_queue_limit ($default_process_limit)\fR"
/* The number of clients that can be waiting for service from a
/* real Postfix SMTP server process.
/* .IP "\fBpostscreen_pre_queue_limit ($default_process_limit)\fR"
/* The number of non-allowlisted clients that can be waiting for
/* a decision whether they will receive service from a real Postfix
/* SMTP server
/* process.
/* .IP "\fBpostscreen_watchdog_timeout (10s)\fR"
/* How much time a \fBpostscreen\fR(8) process may take to respond to
/* a remote SMTP client command or to perform a cache operation before it
/* is terminated by a built-in watchdog timer.
/* STARTTLS CONTROLS
/* .ad
/* .fi
/* .IP "\fBpostscreen_tls_security_level ($smtpd_tls_security_level)\fR"
/* The SMTP TLS security level for the \fBpostscreen\fR(8) server; when
/* a non-empty value is specified, this overrides the obsolete parameters
/* postscreen_use_tls and postscreen_enforce_tls.
/* .IP "\fBtlsproxy_service_name (tlsproxy)\fR"
/* The name of the \fBtlsproxy\fR(8) service entry in master.cf.
/* OBSOLETE STARTTLS SUPPORT CONTROLS
/* .ad
/* .fi
/* These parameters are supported for compatibility with
/* \fBsmtpd\fR(8) legacy parameters.
/* .IP "\fBpostscreen_use_tls ($smtpd_use_tls)\fR"
/* Opportunistic TLS: announce STARTTLS support to remote SMTP clients,
/* but do not require that clients use TLS encryption.
/* .IP "\fBpostscreen_enforce_tls ($smtpd_enforce_tls)\fR"
/* Mandatory TLS: announce STARTTLS support to remote SMTP clients, and
/* require that clients use TLS encryption.
/* MISCELLANEOUS CONTROLS
/* .ad
/* .fi
/* .IP "\fBconfig_directory (see 'postconf -d' output)\fR"
/* The default location of the Postfix main.cf and master.cf
/* configuration files.
/* .IP "\fBdelay_logging_resolution_limit (2)\fR"
/* The maximal number of digits after the decimal point when logging
/* sub-second delay values.
/* .IP "\fBcommand_directory (see 'postconf -d' output)\fR"
/* The location of all postfix administrative commands.
/* .IP "\fBmax_idle (100s)\fR"
/* The maximum amount of time that an idle Postfix daemon process waits
/* for an incoming connection before terminating voluntarily.
/* .IP "\fBprocess_id (read-only)\fR"
/* The process ID of a Postfix command or daemon process.
/* .IP "\fBprocess_name (read-only)\fR"
/* The process name of a Postfix command or daemon process.
/* .IP "\fBsyslog_facility (mail)\fR"
/* The syslog facility of Postfix logging.
/* .IP "\fBsyslog_name (see 'postconf -d' output)\fR"
/* A prefix that is prepended to the process name in syslog
/* records, so that, for example, "smtpd" becomes "prefix/smtpd".
/* .PP
/* Available in Postfix 3.3 and later:
/* .IP "\fBservice_name (read-only)\fR"
/* The master.cf service name of a Postfix daemon process.
/* .PP
/* Available in Postfix 3.5 and later:
/* .IP "\fBinfo_log_address_format (external)\fR"
/* The email address form that will be used in non-debug logging
/* (info, warning, etc.).
/* SEE ALSO
/* smtpd(8), Postfix SMTP server
/* tlsproxy(8), Postfix TLS proxy server
/* dnsblog(8), DNS allow/denylist logger
/* postlogd(8), Postfix logging
/* syslogd(8), system logging
/* README FILES
/* .ad
/* .fi
/* Use "\fBpostconf readme_directory\fR" or "\fBpostconf
/* html_directory\fR" to locate this information.
/* .nf
/* .na
/* POSTSCREEN_README, Postfix Postscreen Howto
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* HISTORY
/* .ad
/* .fi
/* This service was introduced with Postfix version 2.8.
/*
/* Many ideas in \fBpostscreen\fR(8) were explored in earlier
/* work by Michael Tokarev, in OpenBSD spamd, and in MailChannels
/* Traffic Control.
/* 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
/*--*/
/* System library. */
#include <sys_defs.h>
#include <sys/stat.h>
#include <stdlib.h>
/* Utility library. */
#include <msg.h>
#include <mymalloc.h>
#include <events.h>
#include <myaddrinfo.h>
#include <dict_cache.h>
#include <set_eugid.h>
#include <vstream.h>
#include <name_code.h>
#include <inet_proto.h>
/* Global library. */
#include <mail_conf.h>
#include <mail_params.h>
#include <mail_version.h>
#include <mail_proto.h>
#include <data_redirect.h>
#include <string_list.h>
/* Master server protocols. */
#include <mail_server.h>
/* Application-specific. */
#include <postscreen.h>
/*
* Configuration parameters.
*/
char *var_smtpd_service;
char *var_smtpd_banner;
bool var_disable_vrfy_cmd;
bool var_helo_required;
char *var_smtpd_cmd_filter;
char *var_psc_cmd_filter;
char *var_smtpd_forbid_cmds;
char *var_psc_forbid_cmds;
char *var_smtpd_ehlo_dis_words;
char *var_smtpd_ehlo_dis_maps;
char *var_psc_ehlo_dis_words;
char *var_psc_ehlo_dis_maps;
char *var_smtpd_tls_level;
bool var_smtpd_use_tls;
bool var_smtpd_enforce_tls;
char *var_psc_tls_level;
bool var_psc_use_tls;
bool var_psc_enforce_tls;
bool var_psc_disable_vrfy;
bool var_psc_helo_required;
char *var_psc_cache_map;
int var_psc_cache_scan;
int var_psc_cache_ret;
int var_psc_post_queue_limit;
int var_psc_pre_queue_limit;
int var_psc_watchdog;
char *var_psc_acl;
char *var_psc_dnlist_action;
char *var_psc_greet_ttl;
int var_psc_greet_wait;
char *var_psc_pregr_banner;
char *var_psc_pregr_action;
int var_psc_pregr_ttl;
char *var_psc_dnsbl_sites;
char *var_psc_dnsbl_reply;
int var_psc_dnsbl_thresh;
int var_psc_dnsbl_althresh;
char *var_psc_dnsbl_action;
int var_psc_dnsbl_min_ttl;
int var_psc_dnsbl_max_ttl;
int var_psc_dnsbl_tmout;
bool var_psc_pipel_enable;
char *var_psc_pipel_action;
int var_psc_pipel_ttl;
bool var_psc_nsmtp_enable;
char *var_psc_nsmtp_action;
int var_psc_nsmtp_ttl;
bool var_psc_barlf_enable;
char *var_psc_barlf_action;
int var_psc_barlf_ttl;
int var_psc_cmd_count;
int var_psc_cmd_time;
char *var_dnsblog_service;
char *var_tlsproxy_service;
char *var_smtpd_rej_footer;
char *var_psc_rej_footer;
char *var_psc_rej_ftr_maps;
int var_smtpd_cconn_limit;
int var_psc_cconn_limit;
char *var_smtpd_exp_filter;
char *var_psc_exp_filter;
char *var_psc_allist_if;
char *var_psc_uproxy_proto;
int var_psc_uproxy_tmout;
/*
* Global variables.
*/
int psc_check_queue_length; /* connections being checked */
int psc_post_queue_length; /* being sent to real SMTPD */
DICT_CACHE *psc_cache_map; /* cache table handle */
VSTRING *psc_temp; /* scratchpad */
char *psc_smtpd_service_name; /* path to real SMTPD */
int psc_pregr_action; /* PSC_ACT_DROP/ENFORCE/etc */
int psc_dnsbl_action; /* PSC_ACT_DROP/ENFORCE/etc */
int psc_pipel_action; /* PSC_ACT_DROP/ENFORCE/etc */
int psc_nsmtp_action; /* PSC_ACT_DROP/ENFORCE/etc */
int psc_barlf_action; /* PSC_ACT_DROP/ENFORCE/etc */
int psc_min_ttl; /* Update with new tests! */
STRING_LIST *psc_forbid_cmds; /* CONNECT GET POST */
int psc_stress_greet_wait; /* stressed greet wait */
int psc_normal_greet_wait; /* stressed greet wait */
int psc_stress_cmd_time_limit; /* stressed command limit */
int psc_normal_cmd_time_limit; /* normal command time limit */
int psc_stress; /* stress level */
int psc_lowat_check_queue_length; /* stress low-water mark */
int psc_hiwat_check_queue_length; /* stress high-water mark */
DICT *psc_dnsbl_reply; /* DNSBL name mapper */
HTABLE *psc_client_concurrency; /* per-client concurrency */
/*
* Local variables and functions.
*/
static ARGV *psc_acl; /* permanent allow/denylist */
static int psc_dnlist_action; /* PSC_ACT_DROP/ENFORCE/etc */
static ADDR_MATCH_LIST *psc_allist_if; /* allowlist interfaces */
static void psc_endpt_lookup_done(int, VSTREAM *,
MAI_HOSTADDR_STR *, MAI_SERVPORT_STR *,
MAI_HOSTADDR_STR *, MAI_SERVPORT_STR *);
/* psc_dump - dump some statistics before exit */
static void psc_dump(char *unused_service, char **unused_argv)
{
/*
* Dump preliminary cache cleanup statistics when the process commits
* suicide while a cache cleanup run is in progress. We can't currently
* distinguish between "postfix reload" (we should restart) or "maximal
* idle time reached" (we could finish the cache cleanup first).
*/
if (psc_cache_map) {
dict_cache_close(psc_cache_map);
psc_cache_map = 0;
}
}
/* psc_drain - delayed exit after "postfix reload" */
static void psc_drain(char *unused_service, char **unused_argv)
{
int count;
/*
* After "postfix reload", complete work-in-progress in the background,
* instead of dropping already-accepted connections on the floor.
*
* Unfortunately we must close all writable tables, so we can't store or
* look up reputation information. The reason is that we don't have any
* multi-writer safety guarantees. We also can't use the single-writer
* proxywrite service, because its latency guarantees are too weak.
*
* All error retry counts shall be limited. Instead of blocking here, we
* could retry failed fork() operations in the event call-back routines,
* but we don't need perfection. The host system is severely overloaded
* and service levels are already way down.
*
* XXX Some Berkeley DB versions break with close-after-fork. Every new
* version is an improvement over its predecessor.
*
* XXX Don't assume that it is OK to share the same LMDB lockfile descriptor
* between different processes.
*/
if (psc_cache_map != 0 /* XXX && psc_cache_map
requires locking */ ) {
dict_cache_close(psc_cache_map);
psc_cache_map = 0;
}
for (count = 0; /* see below */ ; count++) {
if (count >= 5) {
msg_fatal("fork: %m");
} else if (event_server_drain() != 0) {
msg_warn("fork: %m");
sleep(1);
continue;
} else {
return;
}
}
}
/* psc_service - handle new client connection */
static void psc_service(VSTREAM *smtp_client_stream,
char *unused_service,
char **unused_argv)
{
/*
* For sanity, require that at least one of INET or INET6 is enabled.
* Otherwise, we can't look up interface information, and we can't
* convert names or addresses.
*/
if (inet_proto_info()->ai_family_list[0] == 0)
msg_fatal("all network protocols are disabled (%s = %s)",
VAR_INET_PROTOCOLS, var_inet_protocols);
/*
* This program handles all incoming connections, so it must not block.
* We use event-driven code for all operations that introduce latency.
*
* Note: instead of using VSTREAM-level timeouts, we enforce limits on the
* total amount of time to receive a complete SMTP command line.
*/
non_blocking(vstream_fileno(smtp_client_stream), NON_BLOCKING);
/*
* Look up the remote SMTP client address and port.
*/
psc_endpt_lookup(smtp_client_stream, psc_endpt_lookup_done);
}
/* psc_warn_compat_respectful_logging - compatibility warning */
static void psc_warn_compat_respectful_logging(PSC_STATE *state)
{
msg_info("using backwards-compatible default setting "
VAR_RESPECTFUL_LOGGING "=no for client [%s]:%s",
PSC_CLIENT_ADDR_PORT(state));
warn_compat_respectful_logging = 0;
}
/* psc_endpt_lookup_done - endpoint lookup completed */
static void psc_endpt_lookup_done(int endpt_status,
VSTREAM *smtp_client_stream,
MAI_HOSTADDR_STR *smtp_client_addr,
MAI_SERVPORT_STR *smtp_client_port,
MAI_HOSTADDR_STR *smtp_server_addr,
MAI_SERVPORT_STR *smtp_server_port)
{
const char *myname = "psc_endpt_lookup_done";
PSC_STATE *state;
const char *stamp_str;
int saved_flags;
/*
* Best effort - if this non-blocking write(2) fails, so be it.
*/
if (endpt_status < 0) {
(void) write(vstream_fileno(smtp_client_stream),
"421 4.3.2 No system resources\r\n",
sizeof("421 4.3.2 No system resources\r\n") - 1);
event_server_disconnect(smtp_client_stream);
return;
}
if (msg_verbose > 1)
msg_info("%s: sq=%d cq=%d connect from [%s]:%s",
myname, psc_post_queue_length, psc_check_queue_length,
smtp_client_addr->buf, smtp_client_port->buf);
msg_info("CONNECT from [%s]:%s to [%s]:%s",
smtp_client_addr->buf, smtp_client_port->buf,
smtp_server_addr->buf, smtp_server_port->buf);
/*
* Bundle up all the loose session pieces. This zeroes all flags and time
* stamps.
*/
state = psc_new_session_state(smtp_client_stream, smtp_client_addr->buf,
smtp_client_port->buf,
smtp_server_addr->buf,
smtp_server_port->buf);
/*
* Reply with 421 when the client has too many open connections.
*/
if (var_psc_cconn_limit > 0
&& state->client_info->concurrency > var_psc_cconn_limit) {
msg_info("NOQUEUE: reject: CONNECT from [%s]:%s: too many connections",
state->smtp_client_addr, state->smtp_client_port);
PSC_DROP_SESSION_STATE(state,
"421 4.7.0 Error: too many connections\r\n");
return;
}
/*
* Reply with 421 when we can't forward more connections.
*/
if (var_psc_post_queue_limit > 0
&& psc_post_queue_length >= var_psc_post_queue_limit) {
msg_info("NOQUEUE: reject: CONNECT from [%s]:%s: all server ports busy",
state->smtp_client_addr, state->smtp_client_port);
PSC_DROP_SESSION_STATE(state,
"421 4.3.2 All server ports are busy\r\n");
return;
}
/*
* The permanent allow/denylist has highest precedence.
*/
if (psc_acl != 0) {
switch (psc_acl_eval(state, psc_acl, VAR_PSC_ACL)) {
/*
* Permanently denylisted.
*/
case PSC_ACL_ACT_DENYLIST:
msg_info("%sLISTED [%s]:%s",
var_respectful_logging ? "DENY" : "BLACK",
PSC_CLIENT_ADDR_PORT(state));
if (warn_compat_respectful_logging)
psc_warn_compat_respectful_logging(state);
PSC_FAIL_SESSION_STATE(state, PSC_STATE_FLAG_DNLIST_FAIL);
switch (psc_dnlist_action) {
case PSC_ACT_DROP:
PSC_DROP_SESSION_STATE(state,
"521 5.3.2 Service currently unavailable\r\n");
return;
case PSC_ACT_ENFORCE:
PSC_ENFORCE_SESSION_STATE(state,
"550 5.3.2 Service currently unavailable\r\n");
break;
case PSC_ACT_IGNORE:
PSC_UNFAIL_SESSION_STATE(state, PSC_STATE_FLAG_DNLIST_FAIL);
/*
* Not: PSC_PASS_SESSION_STATE. Repeat this test the next
* time.
*/
break;
default:
msg_panic("%s: unknown denylist action value %d",
myname, psc_dnlist_action);
}
break;
/*
* Permanently allowlisted.
*/
case PSC_ACL_ACT_ALLOWLIST:
msg_info("%sLISTED [%s]:%s",
var_respectful_logging ? "ALLOW" : "WHITE",
PSC_CLIENT_ADDR_PORT(state));
if (warn_compat_respectful_logging)
psc_warn_compat_respectful_logging(state);
psc_conclude(state);
return;
/*
* Other: dunno (don't know) or error.
*/
default:
break;
}
}
/*
* The temporary allowlist (i.e. the postscreen cache) has the lowest
* precedence. This cache contains information about the results of prior
* tests. Allowlist the client when all enabled test results are still
* valid.
*/
if ((state->flags & PSC_STATE_MASK_ANY_FAIL) == 0
&& state->client_info->concurrency == 1
&& psc_cache_map != 0
&& (stamp_str = psc_cache_lookup(psc_cache_map, state->smtp_client_addr)) != 0) {
saved_flags = state->flags;
psc_parse_tests(state, stamp_str, event_time());
state->flags |= saved_flags;
if (msg_verbose)
msg_info("%s: cached + recent flags: %s",
myname, psc_print_state_flags(state->flags, myname));
if ((state->flags & PSC_STATE_MASK_ANY_TODO_FAIL) == 0) {
msg_info("PASS OLD [%s]:%s", PSC_CLIENT_ADDR_PORT(state));
psc_conclude(state);
return;
}
} else if (state->client_info->concurrency > 1) {
saved_flags = state->flags;
psc_todo_tests(state, event_time());
state->flags |= saved_flags;
if (msg_verbose)
msg_info("%s: new + recent flags: %s",
myname, psc_print_state_flags(state->flags, myname));
} else {
saved_flags = state->flags;
psc_new_tests(state);
state->flags |= saved_flags;
if (msg_verbose)
msg_info("%s: new + recent flags: %s",
myname, psc_print_state_flags(state->flags, myname));
}
/*
* Don't allowlist clients that connect to backup MX addresses. Fail
* "closed" on error.
*/
if (addr_match_list_match(psc_allist_if, smtp_server_addr->buf) == 0) {
state->flags |= (PSC_STATE_FLAG_ALLIST_FAIL | PSC_STATE_FLAG_NOFORWARD);
msg_info("%sLIST VETO [%s]:%s", var_respectful_logging ?
"ALLOW" : "WHITE", PSC_CLIENT_ADDR_PORT(state));
if (warn_compat_respectful_logging)
psc_warn_compat_respectful_logging(state);
}
/*
* Reply with 421 when we can't analyze more connections. That also means
* no deep protocol tests when the noforward flag is raised.
*/
if (var_psc_pre_queue_limit > 0
&& psc_check_queue_length - psc_post_queue_length
>= var_psc_pre_queue_limit) {
msg_info("reject: connect from [%s]:%s: all screening ports busy",
state->smtp_client_addr, state->smtp_client_port);
PSC_DROP_SESSION_STATE(state,
"421 4.3.2 All screening ports are busy\r\n");
return;
}
/*
* If the client has no up-to-date results for some tests, do those tests
* first. Otherwise, skip the tests and hand off the connection.
*/
if (state->flags & PSC_STATE_MASK_EARLY_TODO)
psc_early_tests(state);
else if (state->flags & (PSC_STATE_MASK_SMTPD_TODO | PSC_STATE_FLAG_NOFORWARD))
psc_smtpd_tests(state);
else
psc_conclude(state);
}
/* psc_cache_validator - validate one cache entry */
static int psc_cache_validator(const char *client_addr,
const char *stamp_str,
void *unused_context)
{
PSC_STATE dummy_state;
PSC_CLIENT_INFO dummy_client_info;
/*
* This function is called by the cache cleanup pseudo thread.
*
* When an entry is removed from the cache, the client will be reported as
* "NEW" in the next session where it passes all tests again. To avoid
* silly logging we remove the cache entry only after all tests have
* expired longer ago than the cache retention time.
*/
dummy_state.client_info = &dummy_client_info;
psc_parse_tests(&dummy_state, stamp_str, event_time() - var_psc_cache_ret);
return ((dummy_state.flags & PSC_STATE_MASK_ANY_TODO) == 0);
}
/* pre_jail_init - pre-jail initialization */
static void pre_jail_init(char *unused_name, char **unused_argv)
{
VSTRING *redirect;
/*
* Open read-only maps before dropping privilege, for consistency with
* other Postfix daemons.
*/
psc_acl_pre_jail_init(var_mynetworks, VAR_PSC_ACL);
if (*var_psc_acl)
psc_acl = psc_acl_parse(var_psc_acl, VAR_PSC_ACL);
/* Ignore smtpd_forbid_cmds lookup errors. Non-critical feature. */
if (*var_psc_forbid_cmds)
psc_forbid_cmds = string_list_init(VAR_PSC_FORBID_CMDS,
MATCH_FLAG_RETURN,
var_psc_forbid_cmds);
if (*var_psc_dnsbl_reply)
psc_dnsbl_reply = dict_open(var_psc_dnsbl_reply, O_RDONLY,
DICT_FLAG_DUP_WARN);
/*
* Never, ever, get killed by a master signal, as that would corrupt the
* database when we're in the middle of an update.
*/
if (setsid() < 0)
msg_warn("setsid: %m");
/*
* Security: don't create root-owned files that contain untrusted data.
* And don't create Postfix-owned files in root-owned directories,
* either. We want a correct relationship between (file or directory)
* ownership and (file or directory) content. To open files before going
* to jail, temporarily drop root privileges.
*/
SAVE_AND_SET_EUGID(var_owner_uid, var_owner_gid);
redirect = vstring_alloc(100);
/*
* Keep state in persistent external map. As a safety measure we sync the
* database on each update. This hurts on LINUX file systems that sync
* all dirty disk blocks whenever any application invokes fsync().
*
* Start the cache maintenance pseudo thread after dropping privileges.
*/
#define PSC_DICT_OPEN_FLAGS (DICT_FLAG_DUP_REPLACE | DICT_FLAG_SYNC_UPDATE | \
DICT_FLAG_OPEN_LOCK)
if (*var_psc_cache_map)
psc_cache_map =
dict_cache_open(data_redirect_map(redirect, var_psc_cache_map),
O_CREAT | O_RDWR, PSC_DICT_OPEN_FLAGS);
/*
* Clean up and restore privilege.
*/
vstring_free(redirect);
RESTORE_SAVED_EUGID();
/*
* Initialize the dummy SMTP engine.
*/
psc_smtpd_pre_jail_init();
}
/* pre_accept - see if tables have changed */
static void pre_accept(char *unused_name, char **unused_argv)
{
static time_t last_event_time;
time_t new_event_time;
const char *name;
/*
* If some table has changed then stop accepting new connections. Don't
* check the tables more than once a second.
*/
new_event_time = event_time();
if (new_event_time >= last_event_time + 1
&& (name = dict_changed_name()) != 0) {
msg_info("table %s has changed - finishing in the background", name);
event_server_drain();
} else {
last_event_time = new_event_time;
}
}
/* post_jail_init - post-jail initialization */
static void post_jail_init(char *unused_name, char **unused_argv)
{
const NAME_CODE actions[] = {
PSC_NAME_ACT_DROP, PSC_ACT_DROP,
PSC_NAME_ACT_ENFORCE, PSC_ACT_ENFORCE,
PSC_NAME_ACT_IGNORE, PSC_ACT_IGNORE,
PSC_NAME_ACT_CONT, PSC_ACT_IGNORE, /* compatibility */
0, -1,
};
int cache_flags;
const char *tmp;
/*
* This routine runs after the skeleton code has entered the chroot jail.
* Prevent automatic process suicide after a limited number of client
* requests. It is OK to terminate after a limited amount of idle time.
*/
var_use_limit = 0;
/*
* Workaround for parameters whose values may contain "$", and that have
* a default of "$parametername". Not sure if it would be a good idea to
* always to this in the mail_conf_raw(3) module.
*/
if (*var_psc_rej_footer == '$'
&& mail_conf_lookup(var_psc_rej_footer + 1)) {
tmp = mail_conf_eval_once(var_psc_rej_footer);
myfree(var_psc_rej_footer);
var_psc_rej_footer = mystrdup(tmp);
}
if (*var_psc_exp_filter == '$'
&& mail_conf_lookup(var_psc_exp_filter + 1)) {
tmp = mail_conf_eval_once(var_psc_exp_filter);
myfree(var_psc_exp_filter);
var_psc_exp_filter = mystrdup(tmp);
}
/*
* Other one-time initialization.
*/
psc_temp = vstring_alloc(10);
vstring_sprintf(psc_temp, "%s/%s", MAIL_CLASS_PRIVATE, var_smtpd_service);
psc_smtpd_service_name = mystrdup(STR(psc_temp));
psc_dnsbl_init();
psc_early_init();
psc_smtpd_init();
if ((psc_dnlist_action = name_code(actions, NAME_CODE_FLAG_NONE,
var_psc_dnlist_action)) < 0)
msg_fatal("bad %s value: %s", VAR_PSC_DNLIST_ACTION,
var_psc_dnlist_action);
if ((psc_dnsbl_action = name_code(actions, NAME_CODE_FLAG_NONE,
var_psc_dnsbl_action)) < 0)
msg_fatal("bad %s value: %s", VAR_PSC_DNSBL_ACTION,
var_psc_dnsbl_action);
if ((psc_pregr_action = name_code(actions, NAME_CODE_FLAG_NONE,
var_psc_pregr_action)) < 0)
msg_fatal("bad %s value: %s", VAR_PSC_PREGR_ACTION,
var_psc_pregr_action);
if ((psc_pipel_action = name_code(actions, NAME_CODE_FLAG_NONE,
var_psc_pipel_action)) < 0)
msg_fatal("bad %s value: %s", VAR_PSC_PIPEL_ACTION,
var_psc_pipel_action);
if ((psc_nsmtp_action = name_code(actions, NAME_CODE_FLAG_NONE,
var_psc_nsmtp_action)) < 0)
msg_fatal("bad %s value: %s", VAR_PSC_NSMTP_ACTION,
var_psc_nsmtp_action);
if ((psc_barlf_action = name_code(actions, NAME_CODE_FLAG_NONE,
var_psc_barlf_action)) < 0)
msg_fatal("bad %s value: %s", VAR_PSC_BARLF_ACTION,
var_psc_barlf_action);
/* Fail "closed" on error. */
psc_allist_if = addr_match_list_init(VAR_PSC_ALLIST_IF, MATCH_FLAG_RETURN,
var_psc_allist_if);
/*
* Start the cache maintenance pseudo thread last. Early cleanup makes
* verbose logging more informative (we get positive confirmation that
* the cleanup thread runs).
*/
cache_flags = DICT_CACHE_FLAG_STATISTICS;
if (msg_verbose > 1)
cache_flags |= DICT_CACHE_FLAG_VERBOSE;
if (psc_cache_map != 0 && var_psc_cache_scan > 0)
dict_cache_control(psc_cache_map,
CA_DICT_CACHE_CTL_FLAGS(cache_flags),
CA_DICT_CACHE_CTL_INTERVAL(var_psc_cache_scan),
CA_DICT_CACHE_CTL_VALIDATOR(psc_cache_validator),
CA_DICT_CACHE_CTL_CONTEXT((void *) 0),
CA_DICT_CACHE_CTL_END);
/*
* Pre-compute the minimal and maximal TTL.
*/
psc_min_ttl =
PSC_MIN(PSC_MIN(var_psc_pregr_ttl, var_psc_dnsbl_min_ttl),
PSC_MIN(PSC_MIN(var_psc_pipel_ttl, var_psc_nsmtp_ttl),
var_psc_barlf_ttl));
/*
* Pre-compute the stress and normal command time limits.
*/
mail_conf_update(VAR_STRESS, "yes");
psc_stress_cmd_time_limit =
get_mail_conf_time(VAR_PSC_CMD_TIME, DEF_PSC_CMD_TIME, 1, 0);
psc_stress_greet_wait =
get_mail_conf_time(VAR_PSC_GREET_WAIT, DEF_PSC_GREET_WAIT, 1, 0);
mail_conf_update(VAR_STRESS, "");
psc_normal_cmd_time_limit =
get_mail_conf_time(VAR_PSC_CMD_TIME, DEF_PSC_CMD_TIME, 1, 0);
psc_normal_greet_wait =
get_mail_conf_time(VAR_PSC_GREET_WAIT, DEF_PSC_GREET_WAIT, 1, 0);
psc_lowat_check_queue_length = .7 * var_psc_pre_queue_limit;
psc_hiwat_check_queue_length = .9 * var_psc_pre_queue_limit;
if (msg_verbose)
msg_info(VAR_PSC_CMD_TIME ": stress=%d normal=%d lowat=%d hiwat=%d",
psc_stress_cmd_time_limit, psc_normal_cmd_time_limit,
psc_lowat_check_queue_length, psc_hiwat_check_queue_length);
if (psc_lowat_check_queue_length == 0)
msg_panic("compiler error: 0.7 * %d = %d", var_psc_pre_queue_limit,
psc_lowat_check_queue_length);
if (psc_hiwat_check_queue_length == 0)
msg_panic("compiler error: 0.9 * %d = %d", var_psc_pre_queue_limit,
psc_hiwat_check_queue_length);
/*
* Per-client concurrency.
*/
psc_client_concurrency = htable_create(var_psc_pre_queue_limit);
}
MAIL_VERSION_STAMP_DECLARE;
/* main - pass control to the multi-threaded skeleton */
int main(int argc, char **argv)
{
/*
* List smtpd(8) parameters before any postscreen(8) parameters that have
* defaults dependencies on them.
*/
static const CONFIG_STR_TABLE str_table[] = {
VAR_SMTPD_SERVICE, DEF_SMTPD_SERVICE, &var_smtpd_service, 1, 0,
VAR_SMTPD_BANNER, DEF_SMTPD_BANNER, &var_smtpd_banner, 1, 0,
VAR_SMTPD_FORBID_CMDS, DEF_SMTPD_FORBID_CMDS, &var_smtpd_forbid_cmds, 0, 0,
VAR_SMTPD_EHLO_DIS_WORDS, DEF_SMTPD_EHLO_DIS_WORDS, &var_smtpd_ehlo_dis_words, 0, 0,
VAR_SMTPD_EHLO_DIS_MAPS, DEF_SMTPD_EHLO_DIS_MAPS, &var_smtpd_ehlo_dis_maps, 0, 0,
VAR_SMTPD_TLS_LEVEL, DEF_SMTPD_TLS_LEVEL, &var_smtpd_tls_level, 0, 0,
VAR_SMTPD_CMD_FILTER, DEF_SMTPD_CMD_FILTER, &var_smtpd_cmd_filter, 0, 0,
VAR_PSC_CACHE_MAP, DEF_PSC_CACHE_MAP, &var_psc_cache_map, 0, 0,
VAR_PSC_PREGR_BANNER, DEF_PSC_PREGR_BANNER, &var_psc_pregr_banner, 0, 0,
VAR_PSC_PREGR_ACTION, DEF_PSC_PREGR_ACTION, &var_psc_pregr_action, 1, 0,
VAR_PSC_DNSBL_SITES, DEF_PSC_DNSBL_SITES, &var_psc_dnsbl_sites, 0, 0,
VAR_PSC_DNSBL_ACTION, DEF_PSC_DNSBL_ACTION, &var_psc_dnsbl_action, 1, 0,
VAR_PSC_PIPEL_ACTION, DEF_PSC_PIPEL_ACTION, &var_psc_pipel_action, 1, 0,
VAR_PSC_NSMTP_ACTION, DEF_PSC_NSMTP_ACTION, &var_psc_nsmtp_action, 1, 0,
VAR_PSC_BARLF_ACTION, DEF_PSC_BARLF_ACTION, &var_psc_barlf_action, 1, 0,
VAR_PSC_ACL, DEF_PSC_ACL, &var_psc_acl, 0, 0,
VAR_PSC_DNLIST_ACTION, DEF_PSC_DNLIST_ACTION, &var_psc_dnlist_action, 1, 0,
VAR_PSC_FORBID_CMDS, DEF_PSC_FORBID_CMDS, &var_psc_forbid_cmds, 0, 0,
VAR_PSC_EHLO_DIS_WORDS, DEF_PSC_EHLO_DIS_WORDS, &var_psc_ehlo_dis_words, 0, 0,
VAR_PSC_EHLO_DIS_MAPS, DEF_PSC_EHLO_DIS_MAPS, &var_psc_ehlo_dis_maps, 0, 0,
VAR_PSC_DNSBL_REPLY, DEF_PSC_DNSBL_REPLY, &var_psc_dnsbl_reply, 0, 0,
VAR_PSC_TLS_LEVEL, DEF_PSC_TLS_LEVEL, &var_psc_tls_level, 0, 0,
VAR_PSC_CMD_FILTER, DEF_PSC_CMD_FILTER, &var_psc_cmd_filter, 0, 0,
VAR_DNSBLOG_SERVICE, DEF_DNSBLOG_SERVICE, &var_dnsblog_service, 1, 0,
VAR_TLSPROXY_SERVICE, DEF_TLSPROXY_SERVICE, &var_tlsproxy_service, 1, 0,
VAR_PSC_ALLIST_IF, DEF_PSC_ALLIST_IF, &var_psc_allist_if, 0, 0,
VAR_PSC_UPROXY_PROTO, DEF_PSC_UPROXY_PROTO, &var_psc_uproxy_proto, 0, 0,
VAR_PSC_REJ_FTR_MAPS, DEF_PSC_REJ_FTR_MAPS, &var_psc_rej_ftr_maps, 0, 0,
0,
};
static const CONFIG_INT_TABLE int_table[] = {
VAR_PSC_DNSBL_THRESH, DEF_PSC_DNSBL_THRESH, &var_psc_dnsbl_thresh, 1, 0,
VAR_PSC_CMD_COUNT, DEF_PSC_CMD_COUNT, &var_psc_cmd_count, 1, 0,
VAR_SMTPD_CCONN_LIMIT, DEF_SMTPD_CCONN_LIMIT, &var_smtpd_cconn_limit, 0, 0,
0,
};
static const CONFIG_NINT_TABLE nint_table[] = {
VAR_PSC_POST_QLIMIT, DEF_PSC_POST_QLIMIT, &var_psc_post_queue_limit, 5, 0,
VAR_PSC_PRE_QLIMIT, DEF_PSC_PRE_QLIMIT, &var_psc_pre_queue_limit, 10, 0,
VAR_PSC_CCONN_LIMIT, DEF_PSC_CCONN_LIMIT, &var_psc_cconn_limit, 0, 0,
VAR_PSC_DNSBL_ALTHRESH, DEF_PSC_DNSBL_ALTHRESH, &var_psc_dnsbl_althresh, 0, 0,
0,
};
static const CONFIG_TIME_TABLE time_table[] = {
VAR_PSC_CMD_TIME, DEF_PSC_CMD_TIME, &var_psc_cmd_time, 1, 0,
VAR_PSC_GREET_WAIT, DEF_PSC_GREET_WAIT, &var_psc_greet_wait, 1, 0,
VAR_PSC_PREGR_TTL, DEF_PSC_PREGR_TTL, &var_psc_pregr_ttl, 1, 0,
VAR_PSC_DNSBL_MIN_TTL, DEF_PSC_DNSBL_MIN_TTL, &var_psc_dnsbl_min_ttl, 1, 0,
VAR_PSC_DNSBL_MAX_TTL, DEF_PSC_DNSBL_MAX_TTL, &var_psc_dnsbl_max_ttl, 1, 0,
VAR_PSC_PIPEL_TTL, DEF_PSC_PIPEL_TTL, &var_psc_pipel_ttl, 1, 0,
VAR_PSC_NSMTP_TTL, DEF_PSC_NSMTP_TTL, &var_psc_nsmtp_ttl, 1, 0,
VAR_PSC_BARLF_TTL, DEF_PSC_BARLF_TTL, &var_psc_barlf_ttl, 1, 0,
VAR_PSC_CACHE_RET, DEF_PSC_CACHE_RET, &var_psc_cache_ret, 1, 0,
VAR_PSC_CACHE_SCAN, DEF_PSC_CACHE_SCAN, &var_psc_cache_scan, 0, 0,
VAR_PSC_WATCHDOG, DEF_PSC_WATCHDOG, &var_psc_watchdog, 10, 0,
VAR_PSC_UPROXY_TMOUT, DEF_PSC_UPROXY_TMOUT, &var_psc_uproxy_tmout, 1, 0,
VAR_PSC_DNSBL_TMOUT, DEF_PSC_DNSBL_TMOUT, &var_psc_dnsbl_tmout, 1, 0,
0,
};
static const CONFIG_BOOL_TABLE bool_table[] = {
VAR_HELO_REQUIRED, DEF_HELO_REQUIRED, &var_helo_required,
VAR_DISABLE_VRFY_CMD, DEF_DISABLE_VRFY_CMD, &var_disable_vrfy_cmd,
VAR_SMTPD_USE_TLS, DEF_SMTPD_USE_TLS, &var_smtpd_use_tls,
VAR_SMTPD_ENFORCE_TLS, DEF_SMTPD_ENFORCE_TLS, &var_smtpd_enforce_tls,
VAR_PSC_PIPEL_ENABLE, DEF_PSC_PIPEL_ENABLE, &var_psc_pipel_enable,
VAR_PSC_NSMTP_ENABLE, DEF_PSC_NSMTP_ENABLE, &var_psc_nsmtp_enable,
VAR_PSC_BARLF_ENABLE, DEF_PSC_BARLF_ENABLE, &var_psc_barlf_enable,
0,
};
static const CONFIG_RAW_TABLE raw_table[] = {
VAR_SMTPD_REJ_FOOTER, DEF_SMTPD_REJ_FOOTER, &var_smtpd_rej_footer, 0, 0,
VAR_PSC_REJ_FOOTER, DEF_PSC_REJ_FOOTER, &var_psc_rej_footer, 0, 0,
VAR_SMTPD_EXP_FILTER, DEF_SMTPD_EXP_FILTER, &var_smtpd_exp_filter, 1, 0,
VAR_PSC_EXP_FILTER, DEF_PSC_EXP_FILTER, &var_psc_exp_filter, 1, 0,
0,
};
static const CONFIG_NBOOL_TABLE nbool_table[] = {
VAR_PSC_HELO_REQUIRED, DEF_PSC_HELO_REQUIRED, &var_psc_helo_required,
VAR_PSC_DISABLE_VRFY, DEF_PSC_DISABLE_VRFY, &var_psc_disable_vrfy,
VAR_PSC_USE_TLS, DEF_PSC_USE_TLS, &var_psc_use_tls,
VAR_PSC_ENFORCE_TLS, DEF_PSC_ENFORCE_TLS, &var_psc_enforce_tls,
0,
};
/*
* Fingerprint executables and core dumps.
*/
MAIL_VERSION_STAMP_ALLOCATE;
event_server_main(argc, argv, psc_service,
CA_MAIL_SERVER_STR_TABLE(str_table),
CA_MAIL_SERVER_INT_TABLE(int_table),
CA_MAIL_SERVER_NINT_TABLE(nint_table),
CA_MAIL_SERVER_TIME_TABLE(time_table),
CA_MAIL_SERVER_BOOL_TABLE(bool_table),
CA_MAIL_SERVER_RAW_TABLE(raw_table),
CA_MAIL_SERVER_NBOOL_TABLE(nbool_table),
CA_MAIL_SERVER_PRE_INIT(pre_jail_init),
CA_MAIL_SERVER_POST_INIT(post_jail_init),
CA_MAIL_SERVER_PRE_ACCEPT(pre_accept),
CA_MAIL_SERVER_SOLITARY,
CA_MAIL_SERVER_SLOW_EXIT(psc_drain),
CA_MAIL_SERVER_EXIT(psc_dump),
CA_MAIL_SERVER_WATCHDOG(&var_psc_watchdog),
0);
}
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