add purge link when folder contains subfolders.
[squirrelmail.git] / doc / authentication.txt
CommitLineData
03814228 1**********************************************
2IMAP AND SMTP AUTHENTICATION WITH SQUIRRELMAIL
2f854f5f 3$Id$
4Chris Hilts tassium@squirrelmail.org
03814228 5**********************************************
6
a15f9d93 7Prior to SquirrelMail 1.4.0, only plaintext logins for IMAP and SMTP were
8supported. With the release of SquirrelMail 1.4.0, support for the
03814228 9CRAM-MD5 and DIGEST-MD5 auth mechanisms has been added. TLS support has
10also been added. It is possible to use different methods for both IMAP and
11SMTP. TLS is able to be enabled on a per-service basis as well.
12Unless the administrator changes the authentication methods, SquirrelMail
13will default to the "classic" plaintext methods, without TLS.
14
a8855d9c 15Note: There is no point in using TLS if your IMAP server is localhost. You need
16root to sniff the loopback interface, and if you don't trust root, or an attacker
17already has root, the game is over. You've got a lot more to worry about beyond
18having the loopback interface sniffed.
19
03814228 20REQUIREMENTS
21------------
22
23CRAM/DIGEST-MD5
a15f9d93 24* SquirrelMail 1.4.0 or higher
639c7164 25* If you have the mhash extension to PHP, it will automatically
26 be used, which may help performance on heavily loaded servers.
27 ** NOTE: mhash is optional and no longer a requirement **
a15f9d93 28* Digest-MD5 authentication needs PHP XML extension.
03814228 29
30TLS
a15f9d93 31* SquirrelMail 1.4.0 or higher
a8855d9c 32* PHP 4.3.0 or higher (Check Release Notes for PHP 4.3.x information)
a15f9d93 33* The server you wish to use TLS on must have a dedicated port listening for
34 TLS connections. (ie. port 993 for IMAP, 465 for SMTP). See STARTTLS
35 requirements, if you want to use IMAP or SMTP STARTTLS extension.
ad82f7c1 36* If you use PHP 4.3.x, OpenSSL support must be compiled staticly. See
37 PHP bug #29934 (http://bugs.php.net/bug.php?id=29934)
03814228 38
a15f9d93 39STARTTLS
40* SquirrelMail 1.5.1 or higher
41* PHP 5.1.0rc1 or higher (stream_socket_enable_crypto() function)
42* Server with STARTTLS extension support
43
03814228 44CONFIGURATION
45-------------
46
47All configuration is done using conf.pl, under main menu option #2.
48
1c6d997a 49conf.pl can now attempt to detect which mechanisms your servers support.
50You must have set the host and port before attempting to detect, or you
51may get inaccurate results, or a long wait while the connection times out.
52
a15f9d93 53If you get results that you know are wrong when you use auto-detection, send
54information about it to SquirrelMail developers. Provide the results you got,
55the results you expected, and server type, name, and version (eg. "imap,
56Cyrus, v2.1.9").
1c6d997a 57
03814228 58KNOWN ISSUES
59------------
60
61DIGEST-MD5 has three different methods of operation. (qop options "auth",
62"auth-int" and "auth-conf"). This implementation currently supports "auth"
63only. Work is being done to add the other two modes.
64
65DIGEST-MD5 _may_ fail when authenticating with servers that supply more
66than one "realm". I have no servers of this type to test on, so if you do
67and it fails, let me know! (A big help would be for you to telnet to your
68server, start a DIGEST-MD5 auth session, and include the challenge from the
69server in your bug report.)
70
71To get the challenge with IMAP:
e50f5ac2 72 telnet <your server> imap
73 [server says hello]
74 A01 AUTHENTICATE DIGEST-MD5
75 <copy the gobbledygook that the server sends - this is what I need>
76 *
77 [server says auth aborted]
78 A02 LOGOUT
79 [server says goodbye, closes connection]
03814228 80
81To get the challenge with SMTP:
e50f5ac2 82 telnet <your server> smtp
83 [server sends some sort of "hello" banner]
84 EHLO myhostname
85 [server will probably list a bunch of capabilities]
86 AUTH DIGEST-MD5
87 <copy the gobbledygook that the server sends - this is what I need>
88 *
89 [server says auth aborted]
90 QUIT
91 [server says bye, closes connection]
03814228 92
c475d271 93
94OPTIONAL SMTP AUTH CONFIGURATION
95--------------------------------
96
97If you need all users to send mail via an upstream SMTP provider
98(your ISP, for example), and that ISP requires authentication,
99there are two variables that can be added to config_local.php
100that will specify a sitewide SMTP username and password.
101
e50f5ac2 102Set up SMTP authentication to the remote server according to the
103instructions above, then add the following to config_local.php,
c475d271 104replacing <smtp_user> and <smtp_pass> with the username and password
105you'd like to use for the entire site:
106
e50f5ac2 107 $smtp_sitewide_user = '<smtp_user>';
108 $smtp_sitewide_pass = '<smtp_pass>';
c475d271 109
110These values will be used to connect to the SMTP server as long
111as the authentication mechanism is something besides 'none', i.e.
112'login','plain','cram-md5', or 'digest-md5'.
113
a15f9d93 114DEBUGGING SSL ERROR MESSAGES
115----------------------------
116
117SquirrelMail disables display of PHP errors in fsockopen() and
118stream_socket_enable_crypto() function calls. These functions use PHP error
119handler to display connection errors and SquirrelMail tries to handle
120errors without displaying debugging information to end user. If you use TLS or
121STARTTLS and get connection errors, try reproducing them in configtest.php
122script or remove @ symbol from fsockopen() and stream_socket_enable_crypto()
123calls in SquirrelMail scripts.
124
125Possible error messages:
126* SSL: Connection reset by peer in some script.
127 Error happened in IMAP server and server dropped connection. It is possible
128 that error is logged in system or imap logs.
129
130* SSL operation failed with code 1. OpenSSL Error messages: error:14094410:SSL
131routines:func(148):reason(1040) in some script.
132 Error generated by SSL libraries. Locate numbers listed 'SSL
133 routines:func(###):reason(####)' string, find ssl.h file in your OpenSSL
134 sources and locate same numbers listed in '/* Error codes for the SSL
135 functions. */' section. Error define can be self explanatory. If you don't
136 understand it, search for error or that define in your favorite search
137 engine.
138
c475d271 139
03814228 140[End]