NAME¶
mod_gridsite - Grid extensions to Apache httpd
SYNOPSIS¶
LoadModule gridsite_module mod_gridsite.so
DESCRIPTION¶
mod_gridsite is an Apache 2.0 module which enforces access control via
Grid Access Control Lists, and X.509, GSI or VOMS credentials. mod_gridsite
also gives Apache built-in support for the HTTP PUT and DELETE methods, and
formatting of HTML pages with standard headers and footers.
Since mod_gridsite access control within Apache itself, Grid authorization and
the associated verified credentials are available to all technologies
supported by Apache, including static file serving, SSI, CGI, PHP, mod_perl
and Java servlets via a connector to Tomcat.
Operation of mod_gridsite can be configured using runtime directives in Apache's
standard httpd.conf configuration file. The module must first be loaded with a
LoadModule directive:
LoadModule gridsite_module /PATH/TO/MODULES/mod_gridsite.so
The module's behaviour is then controlled by GridSite... directives within
Apache <Directory ...> sections, allowing different directories to use
GridSite features in different ways.
DIRECTIVES¶
- GridSiteIndexes on|off
- Determines whether GridSite generates HTML directory listings. These have
some advantages over standard Apache directory listings (eg the displayed
filenames are never truncated) and will include standard headers and
footers if GridSiteHtmlFormat is on. (Default: GridSiteIndexes off)
- GridSiteIndexHeader file
- If the named file is found in the directory being listed, the file is
included verbatim at the top of the listing and excluded from the
file-by-file listing. The file can either be HTML or plain text (in which
case browsers will be treat it as one HTML paragraph.) (Default: none)
- GridSiteHtmlFormat on|off
- Determines where HTML pages receive additional formatting before being
sent to the client. This includes the "Last modified",
"View page history", "Switch to HTTP(S)", "Print
View" and "Built with GridSite" footer elements. If header
and footer files are found, they will be used too. (Default:
GridSiteHtmlFormat off)
- GridSiteHeadFile file
- GridSiteFootFile file
- Set the filenames to be used for as standard headers and footers for HTML
pages. If the file name begins with "/" then this is used as the
absolute path to that file to be used. Otherwise, for each HTML page, the
directory of that page is tried first, and then parent directories in
ascending order until a header / footer file is found. Header files are
inserted in place of HTML <body[ ...]> tags; footer files in place
of </body>. (These standard files should each include the
appropriate body tag as a replacement.) (Defaults: GridSiteHeadFile
gridsitehead.txt, GridSiteFootFile gridsitefoot.txt)
- GridSiteAuth on|off
- Enables GridSite access control features, using GACL files. The files are
named .gacl and are per-directory. The current directory is tried and then
parent directories in ascending order until a .gacl file is found.
(Default: GridSiteAuth off)
- GridSiteAutoPasscode on|off
- Whether to automatically issue passcodes in response to HTTPS requests
made using a full X.509 certificate (not a GSI proxy.) (Default:
GridSiteAutoPasscode on)
- GridSiteRequirePasscode on|off
- Whether to require passcode cookies when processing HTTPS requests made
using a full X.509 certificate (not a GSI proxy.) (Default:
GridSiteRequirePasscode off)
- GridSiteZoneSlashes number
- How many slashes to include in passcode paths. The path is the prefix of
REQUEST_URI that includes that number of slashes. Path matching is checked
by mod_gridsite in addition to any selection of cookies by path made by
the browser. (Default: GridSiteZoneSlashes 1)
- GridSiteAdminList uri
- All members of the DN List with name "uri" receive the full set
of permissions, irrespective of per-directory .gacl files. People in this
group have full control over the whole site. (Default: none)
- GridSiteGSIProxyLimit limit
- When using GSI Proxy credentials, proxies with delegation depth greater
than "limit" will be ignored by mod_gridsite authorization
decisions. A limit of zero implies only full X.509 certificates (and no
proxies) will be accepted. A limit of 1 implies that only the initial
proxy, usually created on the user's own machine, is acceptable. Higher
levels lead to proxies on remote machines, eg used by running jobs, being
accepted. (Default: GridSiteGSIProxyLimit 1)
- GridSiteMethods [GET] [PUT] [DELETE] [MOVE]
- Specifies which HTTP methods are supported by GridSite. GET (and HEAD) are
always supported. PUT and DELETE support is turned on by this directive,
subject to a positive statement that write permission is allowed for the
directory in question, by a GACL file. (Default: GridSite GET)
- GridSiteDNlists directory1[:directory2[:directory3]...]
- Sets up the DN List path used by GACL for evaluating <dn-list>
credentials. If this directive is not used, then GACL will use the
GRST_DN_LISTS variable from Apache's own environment. If that is not set
either, then /etc/grid-security/dn-lists is searched. (Default: none)
- GridSiteDNlistsURI uri
- If GridSiteDNlistsURI is used, then the URI given appears to be populated
with all the DN lists on the current DN lists path which match the current
server. That is, for server https://example.org/ with DN lists URI
/dn-lists/, all DN lists with URLs starting https://example.org/dn-lists/
will appear to be present in /dn-lists/, irrespective of where in the path
they are stored. (Default: none) <p>
- GridSiteAdminURI uri
- GridSiteAdminURI gives the absolute URI on the server of the GridSite
Admin CGI program, which is used for file management, HTML and GACL
editing. This should be used in conjunction with the standard Apache
directive ScriptAlias to map that URI to the real-gridsite-admin.cgi
executable. For example:
ScriptAlias /real-gridsite-admin.cgi /PATH/TO/real-gridsite-admin.cgi
This URI is always reached by an internal redirection from the value set by
GridSiteAdminFile, and is never visible to users. (Default: none)
- GridSiteAdminFile cgifilename
- If GridSiteAdminURI is set, then the cgifilename of GridSiteAdminFile
appears to be present in all directories when explicitly requested (it
does not appear in directory listings.) Requests for these ghost CGI URIs
are internally redirected to the value set by GridSiteAdminURI. (Default:
GridSiteAdminFile gridsite-admin.cgi)
- GridSiteEnvs on|off
- This makes mod_gridsite export several variables into the environment of
CGI programs and other dynamic content systems. The variable names are
listed below. For gridsite-admin.cgi mechanism to work, this switch must
be left in its default state of on. (Default: GridSiteEnvs on)
- GridSiteEditable [ext1 [ext2 [ext3] ...]]]
- A space-separated list of file extensions which can safely be edited by
the GridSite Text/HTML editor. The extensions are given without the
initial dot. This directive must apply to the gridsite-admin.cgi
executable, rather than just to the files it manages. This is most easily
achieved by placing GridSiteEditable in the main section of the virtual
host, outside any Directory or Location containers. (Default:
GridSiteEditable txt shtml html htm css js php jsp)
- GridSiteHelpURI uri
- If set, gives the URI to use for "Website Help" links in HTML
page footers. (Default: none)
- GridSiteLoginURI uri
- If set, gives the URI prefix to use for login/logout links in page
footers. The text "Login/Logout" will be a link to the prefix
followed by the value of REQUEST_URI for the page in question. (Default:
none)
- GridSiteLink on|off
- Turns off the link in the HTML page footers which gives credit to
GridSite. (Default: GridSiteLink on)
- GridSiteUnzip path
- If "path" is set by this directive, then real-gridsite-admin.cgi
will offer to list the contents of .zip archives on the server. Users with
write access are able to unpack the contents into the same directory as
the .zip file. The value of "path" must point to the
location of the unzip binary. (Default: none)
- GridSiteGridHTTP on|off
- Enable GridHTTP for this server, virtual server or directory: HTTPS
requests made with the header Upgrade: GridHTTP/1.0 will be
redirected to an HTTP version of the file. (Default: off)
- GridSiteGridHTTPport port
- Sets the port to use for the unencrypted HTTP component of GridHTTP
HTTPS->HTTP transfers. The same setting will be used for all virtual
hosts which support GridHTTP. (Default: 777)
- GridSiteSessionsDir path
- Location of authentication cookies and SSL session credentials directory,
relative to ServerRoot. Used by GridHTTP to record the credentials
obtained via HTTPS, and available to the corresponding HTTP request or
subsequent HTTPS requests following a session restart. (Default:
/var/www/sessions)
- GridSiteACLFormat GACL|XACML
- Format to use when writing .gacl files. (Both formats are automatically
recognised when reading.) (Default: GACL)
- GridSiteACLPath path
- Specify the absolute or relative (to ServerRoot) path of the ACL file
governing this section of the server's URL space. This can be applied to
virtual URL spaces provided by other modules, such as DAV or SVN, using
the Apache <Location> container. If the path contains %0, it is
replaced by this virtual server's hostname. If it contains %1, %2, ... it
is replaced with the 1st, 2nd, ... component of the request's URI,
separated by slashes and counting from immediately after the initial
slash.
- GridSiteExecMethod nosetuid|suexec|X509DN|directory
- Execution strategy for CGI scripts and executables. For options other than
nosetuid, suexec (or gsexec renamed suexec) must installed. For X509DN and
directory, gsexec must be installed, as suexec. See gsexec(8) for
an explanation of the different execution strategies. (Default: nosetuid)
- GridSiteUserGroup user group
- Unix user and group when using suexec (or gsexec as suexec.) This is
equivalent to the suexec SuexecUserGroup directive, but can be specified
on a per-directory basis. (Default: none)
- GridSiteDiskMode GroupNone|GroupRead|GroupWrite WorldNone|WorldRead
- The file creation permissions mode, taking two arguments to specify the
group and other permissions. The mode always includes read and write
permission for the CGI user itself. (Default: GroupNone WorldNone)
- GridSiteCastUniPort port
- The UDP unicast port to listen on for HTCP queries, and from which
to send replies to HTCP unicast and multicast queries. Ideally, this
should be a privileged port below 1024. This directive may not appear
within a virtual server. (Default: 777)
- GridSiteCastGroup group[:port]
- A UDP multicast group on which to listen for HTCP queries, plus an
optional port. If no port is given, then 777 is used. Multiple
GridSiteCastGroup directives can be given to cause the UDP responder to
listen to more than one multicast group. This directive may not appear
within a virtual server.
- GridSiteCastAlias URL-prefix path-prefix
- Maps SiteCast generic URLs to the local filesystem. When processing HTCP
queries, matching SiteCast URLs will have URL-prefix stripped off and the
remaining portion of the URL added to path-prefix to construct a local
path and filename. If a file is found with that name, a SiteCast HTCP
response will be returned to the querying host. Otherwise the queries are
ignored. This directive may appear within virtual servers, and the virtual
server's servername and first port will determine the host and port name
used to construct the transfer URL.
ENVIRONMENT¶
The following variables are present in the environment of CGI programs and other
dynamic content systems if the
GridSiteEnvs on directive is in effect.
- GRST_PERM
- Numerical value of the permission bit-map obtained by comparing the user
with the GACL in force. (These should be tested using the
GRSTgaclPermHasXXXX functions from GACL.)
- GRST_PASSCODE_COOKIE
- Value of GRIDHTTP_PASSCODE cookie that should be returned when using a
double-submit cookie procedure to guard against Cross Site Request Forgery
(CSRF) attacks. This is only set if a valid passcode file was found in the
server's sessions directory.
- GRST_ADMIN_LIST
- URI of the DN List, listing people with full admin and write access to the
whole site.
- GRST_GSIPROXY_LIMIT
- Maximum valid delegation level for GSI Proxies.
- GRST_DIR_PATH
- Absolute path in the local filesystem to the directory holding the file
being requested.
- GRST_DESTINATION_TRANSLATED
- Present if a WebDAV Destination: header was given in the request
with a local URL. Contains the translation of the URL given into an
absolute path in the local filesystem.
- GRST_HELP_URI
- URI of website help pages set by GridSiteHelpURI directive.
- GRST_ADMIN_FILE
- Filename of per-directory ghost gridsite-admin.cgi program. (This is used
by real-gridsite-admin.cgi to construct links in its pages.)
- GRST_EDITABLE
- Space-separated list of extensions which can safely be edited with a
Text/HTML editor.
- GRST_HEAD_FILE and GRST_FOOT_FILE
- Filenames of standard header and footer files.
- GRST_DN_LISTS
- DN lists search path.
- GRST_DN_LISTS_URI
- Directory of virtual URIs used to publish this site's DN Lists.
- GRST_UNZIP
- Full path to the unzip(1) binary, used to list and unpack .zip
files.
- GRST_NO_LINK
- If set, do not include credit links to GridSite in page footers.
- GRST_ACL_FORMAT
- Format to use when writing .gacl files: either GACL or XACML.
- GRST_EXEC_METHOD
- Specified by GridSiteExecMethod either suexec, X509DN or directory.
- GRST_EXEC_DIRECTORY
- The directory containing the CGI script or executable (used by gsexec to
determine which pool account to use in directory mapping mode.)
- GRST_DISK_MODE
- The Apache disk permission modes bit pattern, in hexadecimal,
starting with 0x. (Similar to the Unix bit pattern, except with
hexadecimal rather than octal values: eg 0x600 [Apache] vs 0600 [Unix] are
both read/write for user only.)
AUTHOR¶
Andrew McNab <Andrew.McNab@manchester.ac.uk>
mod_gridsite is part of GridSite:
http://www.gridsite.org/
SEE ALSO¶
htcp(1), httpd(8), gsexec(8)