Viewing file:  mod_wrap2_sql.html (8.33 KB) -rw-r--r--
Select action/file-type:
 (+) | (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
ProFTPD module mod_wrap2_sql
ProFTPD module mod_wrap2_sql
This submodule provides the SQL database "driver" for storing
IP/DNS-based access control information in SQL tables.
This mod_wrap2 submodule is contained in the
mod_wrap2_sql.c file, and is not compiled by default. See the
mod_wrap2 installation
instructions.
Author
Please contact TJ Saunders <tj at castaglia.org> with any
questions, concerns, or suggestions regarding this module.
The mod_wrap2_sql module supports the "sql" string
for the source-type parameter of the
WrapUserTables,
WrapGroupTables,
and
WrapTables,
configuration directives. If the "sql" source-type is used,
then the source-info parameter must be as described below. Note
that support for SQL-based access tables requires the use of
mod_sql.
mod_wrap2_sql requires two to four SQL-related configuration
directives: SQLConnectInfo, and two, possibly four,
SQLNamedQuery directives. The SQLConnectInfo is
necessary to allow the module to connect to the SQL database. The other
directives define the SQL queries that will be used by mod_wrap2
for its retrieval operations involving access data.
When using SQL tables and mod_sql, the access tables should appear
in the database named by the SQLConnectInfo directive, which
will probably also contain the authentication information tables. This way
your proftpd-specific tables are kept together. Also, it is
probably better to use a connection policy of PERSESSION, otherwise there will
be more overhead associated with each new connection made to the database for
each transaction.
One SQLNamedQuery is needed to SELECT access
information from the allow table, and one to SELECT access
information from the deny table. These queries should return a list of words,
where each word is a host name, host address, pattern, or wildcard (see
here for how these things are
defined). Failure to define either of these SQLNamedQuery
directives will cause an error during mod_wrap2_sql's operation.
Optionally, other SQLNamedQuery directives can be defined
to look up access options from
the allow and deny tables.
For SQL tables, the format for the WrapUserTables,
WrapGroupTables, and WrapTables directives is:
WrapTables sql:/allow-SQLNamedQuery[/allow-options-SQLNamedQuery] \
sql:deny-SQLNamedQuery[/deny-options-SQLNamedQuery]
where the allow-options-SQLNamedQuery and
deny-options-SQLNamedQuery portions of the string are
optional.
SQL Access Tables Example
Here are example SQLNamedQuery directives to help demonstrate
how the mod_sql hooks are used by mod_wrap2_sql.
These example SQL statements assume the existence of two tables: a
wrapallow table that defines allowed clients, and a
wrapdeny table that defines the denied clients.
SQLNamedQuery get-allowed-clients SELECT "allowed FROM wrapallow WHERE name = '%{0}'"
SQLNamedQuery get-denied-clients SELECT "denied FROM wrapdeny WHERE name = '%{0}'"
...
SQLNamedQuery get-all-allowed-clients SELECT "allowed FROM wrapallow"
SQLNamedQuery get-all-denied-clients SELET "denied FROM wrapdeny"
These define the SQL statements to return the required list of words. The
%{0} meta sequence will be substituted with the name being looked
up (e.g. user name for WrapUserTables, primary group name
for WrapGroupTables, or the empty string for
WrapTables).
If the administrator wants to make use of access options, then queries for
those options would need to be similarly defined:
SQLNamedQuery get-allowed-options SELECT "options FROM wrapallow WHERE name = '%{0}'"
SQLNamedQuery get-denied-options SELECT "options FROM wrapdeny WHERE name = '%{0}'"
Now, using the above defined queries, the table configuration directives would
be:
# Access tables for users (with options)
WrapUserTables user1,user2 sql:/get-allowed-clients/get-allowed-options \
sql:/get-denied-clients/get-denied-options
# Access tables for groups (with options). Note that this directive
# uses the same SELECT queries used for looking up users. If group
# access information is in a different table, then separate group-specific
# SQLNamedQuery directives will need to be used.
WrapGroupTables group1,group2 sql:/get-allowed-clients/get-allowed-options \
sql:/get-denied-clients/get-denied-options
# Access tables for everyone else (without options). Note that these
# query names are different, since these tables are global, not
# per-user/group.
WrapTables sql:/get-all-allowed-clients sql:/get-all-denied-clients
One thing to keep in mind, however, is that the %{0} part of an
SQL query will only be expanded with the client's USER argument
for WrapUserTables queries. For WrapGroupTables
queries, that %{0} will be expanded to contain the primary group
name of the connecting client's USER. For WrapTables
queries, an empty string is used. This means that the same query cannot
often be easily reused.
Example Schema
Here are some example table schema for SQL-based access tables:
- Per-User/Group Allow Table
CREATE TABLE wrapallow (
name VARCHAR(64) PRIMARY KEY,
allowed VARCHAR(255) NOT NULL,
options VARCHAR(255)
);
- Per-User/Group Deny Table
CREATE TABLE wrapdeny (
name VARCHAR(64) PRIMARY KEY,
denied VARCHAR(255) NOT NULL,
options VARCHAR(255)
);
- Per-IP Allow Table
CREATE TABLE wrapallowip (
allowed VARCHAR(128) PRIMARY KEY
);
The idea here is that the allowed column would contain the IP
address of the client to be allowed; one row per IP address. The
SQLNamedQuery for this would then be:
SQLNamedQuery get-allowed-client-ip SELECT "allowed FROM wrapallowip WHERE allowed = '%a'"
Yes, this looks odd, to be returning the value that is used for the lookup,
but this interface is necessary due to the mod_wrap2 engine.
- Per-IP Deny Table
CREATE TABLE wrapdenyip (
denied VARCHAR(128) PRIMARY KEY
);
The idea here is that the denied column would contain the IP
address of the client to be denied; one row per IP address. The
SQLNamedQuery for this would then be:
SQLNamedQuery get-denied-client-ip SELECT "denied FROM wrapdenyip WHERE denied = '%a'"
Yes, this looks odd, to be returning the value that is used for the lookup,
but this interface is necessary due to the mod_wrap2 engine.
When constructing the client and options lists to return to
mod_wrap2's access control engine, mod_wrap2_sql will
parse each returned row separately, handling both comma- and space-limited
names in a row, into client list items. This means that the administrator can
store multiple client and option tokens in multiple rows, as in the above
schema, or the administrator can choose to store all of the clients and/or
options in a single row, in an appropriately formatted string.
© Copyright 2000-2017 TJ Saunders
All Rights Reserved
|