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diff --git a/man/man8/tlsmgr.8 b/man/man8/tlsmgr.8 new file mode 100644 index 0000000..c4e594c --- /dev/null +++ b/man/man8/tlsmgr.8 @@ -0,0 +1,208 @@ +.TH TLSMGR 8 +.ad +.fi +.SH NAME +tlsmgr +\- +Postfix TLS session cache and PRNG manager +.SH "SYNOPSIS" +.na +.nf +\fBtlsmgr\fR [generic Postfix daemon options] +.SH DESCRIPTION +.ad +.fi +The \fBtlsmgr\fR(8) manages the Postfix TLS session caches. +It stores and retrieves cache entries on request by +\fBsmtpd\fR(8) and \fBsmtp\fR(8) processes, and periodically +removes entries that have expired. + +The \fBtlsmgr\fR(8) also manages the PRNG (pseudo random number +generator) pool. It answers queries by the \fBsmtpd\fR(8) +and \fBsmtp\fR(8) +processes to seed their internal PRNG pools. + +The \fBtlsmgr\fR(8)'s PRNG pool is initially seeded from +an external source (EGD, /dev/urandom, or regular file). +It is updated at configurable pseudo\-random intervals with +data from the external source. It is updated periodically +with data from TLS session cache entries and with the time +of day, and is updated with the time of day whenever a +process requests \fBtlsmgr\fR(8) service. + +The \fBtlsmgr\fR(8) saves the PRNG state to an exchange file +periodically and when the process terminates, and reads +the exchange file when initializing its PRNG. +.SH "SECURITY" +.na +.nf +.ad +.fi +The \fBtlsmgr\fR(8) is not security\-sensitive. The code that maintains +the external and internal PRNG pools does not "trust" the +data that it manipulates, and the code that maintains the +TLS session cache does not touch the contents of the cached +entries, except for seeding its internal PRNG pool. + +The \fBtlsmgr\fR(8) can be run chrooted and with reduced privileges. +At process startup it connects to the entropy source and +exchange file, and creates or truncates the optional TLS +session cache files. + +With Postfix version 2.5 and later, the \fBtlsmgr\fR(8) no +longer uses root privileges when opening cache files. These +files should now be stored under the Postfix\-owned +\fBdata_directory\fR. As a migration aid, an attempt to +open a cache file under a non\-Postfix directory is redirected +to the Postfix\-owned \fBdata_directory\fR, and a warning +is logged. +.SH DIAGNOSTICS +.ad +.fi +Problems and transactions are logged to \fBsyslogd\fR(8) +or \fBpostlogd\fR(8). +.SH BUGS +.ad +.fi +There is no automatic means to limit the number of entries in the +TLS session caches and/or the size of the TLS cache files. +.SH "CONFIGURATION PARAMETERS" +.na +.nf +.ad +.fi +Changes to \fBmain.cf\fR are not picked up automatically, +because \fBtlsmgr\fR(8) is a persistent processes. Use the +command "\fBpostfix reload\fR" after a configuration change. + +The text below provides only a parameter summary. See +\fBpostconf\fR(5) for more details including examples. +.SH "TLS SESSION CACHE" +.na +.nf +.ad +.fi +.IP "\fBlmtp_tls_loglevel (0)\fR" +The LMTP\-specific version of the smtp_tls_loglevel +configuration parameter. +.IP "\fBlmtp_tls_session_cache_database (empty)\fR" +The LMTP\-specific version of the smtp_tls_session_cache_database +configuration parameter. +.IP "\fBlmtp_tls_session_cache_timeout (3600s)\fR" +The LMTP\-specific version of the smtp_tls_session_cache_timeout +configuration parameter. +.IP "\fBsmtp_tls_loglevel (0)\fR" +Enable additional Postfix SMTP client logging of TLS activity. +.IP "\fBsmtp_tls_session_cache_database (empty)\fR" +Name of the file containing the optional Postfix SMTP client +TLS session cache. +.IP "\fBsmtp_tls_session_cache_timeout (3600s)\fR" +The expiration time of Postfix SMTP client TLS session cache +information. +.IP "\fBsmtpd_tls_loglevel (0)\fR" +Enable additional Postfix SMTP server logging of TLS activity. +.IP "\fBsmtpd_tls_session_cache_database (empty)\fR" +Name of the file containing the optional Postfix SMTP server +TLS session cache. +.IP "\fBsmtpd_tls_session_cache_timeout (3600s)\fR" +The expiration time of Postfix SMTP server TLS session cache +information. +.SH "PSEUDO RANDOM NUMBER GENERATOR" +.na +.nf +.ad +.fi +.IP "\fBtls_random_source (see 'postconf -d' output)\fR" +The external entropy source for the in\-memory \fBtlsmgr\fR(8) pseudo +random number generator (PRNG) pool. +.IP "\fBtls_random_bytes (32)\fR" +The number of bytes that \fBtlsmgr\fR(8) reads from $tls_random_source +when (re)seeding the in\-memory pseudo random number generator (PRNG) +pool. +.IP "\fBtls_random_exchange_name (see 'postconf -d' output)\fR" +Name of the pseudo random number generator (PRNG) state file +that is maintained by \fBtlsmgr\fR(8). +.IP "\fBtls_random_prng_update_period (3600s)\fR" +The time between attempts by \fBtlsmgr\fR(8) to save the state of +the pseudo random number generator (PRNG) to the file specified +with $tls_random_exchange_name. +.IP "\fBtls_random_reseed_period (3600s)\fR" +The maximal time between attempts by \fBtlsmgr\fR(8) to re\-seed the +in\-memory pseudo random number generator (PRNG) pool from external +sources. +.SH "MISCELLANEOUS CONTROLS" +.na +.nf +.ad +.fi +.IP "\fBconfig_directory (see 'postconf -d' output)\fR" +The default location of the Postfix main.cf and master.cf +configuration files. +.IP "\fBdata_directory (see 'postconf -d' output)\fR" +The directory with Postfix\-writable data files (for example: +caches, pseudo\-random numbers). +.IP "\fBdaemon_timeout (18000s)\fR" +How much time a Postfix daemon process may take to handle a +request before it is terminated by a built\-in watchdog timer. +.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. +.SH "SEE ALSO" +.na +.nf +smtp(8), Postfix SMTP client +smtpd(8), Postfix SMTP server +postconf(5), configuration parameters +master(5), generic daemon options +master(8), process manager +postlogd(8), Postfix logging +syslogd(8), system logging +.SH "README FILES" +.na +.nf +.ad +.fi +Use "\fBpostconf readme_directory\fR" or +"\fBpostconf html_directory\fR" to locate this information. +.na +.nf +TLS_README, Postfix TLS configuration and operation +.SH "LICENSE" +.na +.nf +.ad +.fi +The Secure Mailer license must be distributed with this software. +.SH HISTORY +.ad +.fi +This service was introduced with Postfix version 2.2. +.SH "AUTHOR(S)" +.na +.nf +Lutz Jaenicke +BTU Cottbus +Allgemeine Elektrotechnik +Universitaetsplatz 3\-4 +D\-03044 Cottbus, Germany + +Adapted by: +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 |