Postfix Overview - Introduction - SCN Research

More documents

Recommendations

Info

SPAWN(8) SPAWN(8) Page 1 of 2 NAME spawn - Postfix external command spawner SYNOPSIS spawn [generic Postfix daemon options] command_attributes... DESCRIPTION The spawn daemon provides the Postfix equivalent of inetd. It listens on a port as specified in the Postfix master.cf file and spawns an external command whenever a connection is established. The connection can be made over local IPC (such as UNIX-domain sockets) or over non-local IPC (such as TCP sockets). The command's standard input, output and error streams are connected directly to the communication endpoint. This daemon expects to be run from the master(8) process manager. COMMAND ATTRIBUTE SYNTAX The external command attributes are given in the master.cf file at the end of a service definition. The syntax is as follows: user=username (required) user=username:groupname The external command is executed with the rights of the specified username. The software refuses to execute commands with root privileges, or with the privileges of the mail system owner. If groupname is specified, the corresponding group ID is used instead of the group ID of of username. argv=command... (required) The command to be executed. This must be specified as the last command attribute. The command is executed directly, i.e. without interpretation of shell meta characters by a shell command interpreter. BUGS In order to enforce standard Postfix process resource controls, the spawn daemon runs only one external command at a time. As such, it presents a noticeable overhead by wasting precious process resources. The spawn daemon is expected to be replaced by a more structural solution. DIAGNOSTICS The spawn daemon reports abnormal child exits. Problems are logged to syslogd(8). SECURITY This program needs root privilege in order to execute external commands as the specified user. It is therefore security sensitive. However the spawn daemon does not talk to the external command and thus is not vulnerable to data-driven attacks. CONFIGURATION PARAMETERS The following main.cf parameters are especially relevant http://www.porcupine.org/postfix-mirror/spawn.8.html 6/26/01
to this program. See the Postfix main.cf file for syntax details and for default values. Use the postfix reload command after a configuration change. Page 2 of 2 Miscellaneous export_environment List of names of environment parameters that can be exported to non-Postfix processes. mail_owner The process privileges used while not running an external command. Resource control service_command_time_limit The amount of time the command is allowed to run before it is killed with force. The service name is the name of the entry in the master.cf file. The default time limit is given by the global command_time_limit configuration parameter. SEE ALSO master(8) process manager syslogd(8) system logging LICENSE The Secure Mailer license must be distributed with this software. AUTHOR(S) Wietse Venema IBM T.J. Watson Research P.O. Box 704 Yorktown Heights, NY 10598, USA 1 http://www.porcupine.org/postfix-mirror/spawn.8.html 6/26/01
Page 1:
Postfix Overview - Introduction Pag
Page 4 and 5:
Postfix Overview - Goals and Featur
Page 6 and 7:
Postfix Overview - Global Architect
Page 8 and 9:
Postfix Overview - Queue Management
Page 10 and 11:
Postfix Overview - Security assista
Page 12 and 13:
Postfix Anatomy - Receiving Mail Pa
Page 14 and 15:
Postfix Anatomy - Delivering Mail p
Page 16 and 17:
Postfix Anatomy - Command-line Util
Page 18 and 19:
Postfix Configuration - Basics What
Page 20 and 21:
Postfix Configuration - Basics My o
Page 23 and 24:
Postfix Configuration - UCE Control
Page 25 and 26:
Page 27 and 28:
Page 29 and 30:
Page 31 and 32:
Page 33 and 34:
Postfix Rate Controls Page 1 of 4 P
Page 35 and 36:
Postfix Rate Controls The defer_tra
Page 37 and 38:
Postfix Configuration - Resource Co
Page 39:
Postfix Configuration - Resource Co
Page 42 and 43:
Postfix Configuration - Address Man
Page 44 and 45:
Postfix Configuration - Address Man
Page 47 and 48:
ACCESS(5) ACCESS(5) Page 1 of 3 NAM
Page 49:
1 Page 3 of 3 http://www.porcupine.
Page 52 and 53:
ited to regular files. For example,
Page 54 and 55:
BOUNCE(8) BOUNCE(8) Page 1 of 2 NAM
Page 56 and 57:
CANONICAL(5) CANONICAL(5) Page 1 of
Page 58 and 59:
canonical_maps List of canonical ma
Page 60 and 61:
CONFIGURATION PARAMETERS The follow
Page 62 and 63:
BOUNCE(8) BOUNCE(8) Page 1 of 2 NAM
Page 64 and 65:
FLUSH(8) FLUSH(8) Page 1 of 3 NAME
Page 66 and 67:
fast_flush_purge_time Remove an emp
Page 68 and 69:
Problems and transactions are logge
Page 70 and 71:
parameter. Page 4 of 5 Timeout cont
Page 72 and 73:
LOCAL(8) LOCAL(8) Page 1 of 7 NAME
Page 74 and 75:
estricts delivery to external comma
Page 76 and 77:
details and for default values. Use
Page 78 and 79:
that is written to upon delivery).
Page 80 and 81:
Page 2 of 3 SIGTERM Upon receipt of
Page 82 and 83:
PCRE_TABLE(5) PCRE_TABLE(5) Page 1
Page 84 and 85:
PICKUP(8) PICKUP(8) Page 1 of 2 NAM
Page 86 and 87: PIPE(8) PIPE(8) Page 1 of 5 NAME pi
Page 88 and 89: This macro expands to the extension
Page 90 and 91: ounce(8) non-delivery status report
Page 92 and 93: -r When updating a table, do not wa
Page 94 and 95: POSTCAT(1) POSTCAT(1) Page 1 of 1 N
Page 96 and 97: POSTDROP(1) POSTDROP(1) Page 1 of 2
Page 98 and 99: POSTFIX(1) POSTFIX(1) Page 1 of 2 N
Page 100 and 101: POSTKICK(1) POSTKICK(1) Page 1 of 2
Page 102 and 103: POSTLOCK(1) POSTLOCK(1) Page 1 of 2
Page 104 and 105: POSTLOG(1) POSTLOG(1) Page 1 of 1 N
Page 106 and 107: default, postmap creates a new data
Page 108 and 109: POSTSUPER(1) POSTSUPER(1) Page 1 of
Page 110 and 111: LICENSE The Secure Mailer license m
Page 112 and 113: The queue manager implements a vari
Page 114 and 115: This parameter also limits the size
Page 116 and 117: REGEXP_TABLE(5) REGEXP_TABLE(5) Pag
Page 118 and 119: RELOCATED(5) RELOCATED(5) Page 1 of
Page 120 and 121: Yorktown Heights, NY 10598, USA Pag
Page 122 and 123: Page 2 of 5 -C config_file (ignored
Page 124 and 125: Page 4 of 5 DIAGNOSTICS Problems ar
Page 126 and 127: SHOWQ(8) SHOWQ(8) Page 1 of 1 NAME
Page 128 and 129: command after a configuration chang
Page 130 and 131: Page 4 of 4 smtp_helo_timeout Timeo
Page 132 and 133: Support older Microsoft clients tha
Page 134 and 135: Page 4 of 5 smtpd_hard_error_limit
Page 138 and 139: TRANSPORT(5) TRANSPORT(5) Page 1 of
Page 140 and 141: the entire domain being looked up.
Page 142 and 143: details and for default values. Use
Page 144 and 145: VIRTUAL(5) VIRTUAL(5) Page 1 of 4 N
Page 146 and 147: site is equal to $myorigin, when si
Page 148 and 149: VIRTUAL(8) VIRTUAL(8) Page 1 of 4 N
Page 150 and 151: Specifies a minimum uid that will b
show all

Postfix Overview - Introduction - SCN Research

Create successful ePaper yourself

Delete template?

Save as template?