Copyright © 2002, 2003 FhG FOKUS
Copyright © 2005 voice-system
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Table of Contents
List of Examples
db_url parameter usageuser_column parameter usagedomain_column parameter usagepassword_column parameter usagepassword_column_2 parameter usagecalculate_ha1 parameter usageuse_domain parameter usageload_credentials parameter usagewww_authorize usageTable of Contents
This module contains all authentication related functions that need the access to the database. This module should be used together with auth module, it cannot be used independently because it depends on the module. Select this module if you want to use database to store authentication information like subscriber usernames and passwords. If you want to use radius authentication, then use auth_radius instead.
The module depends on the following modules (in the other words the listed modules must be loaded before this module):
auth -- Generic authentication functions
database -- Any database module (currently mysql, postgres, dbtext)
This is URL of the database to be used. Value of the parameter depends on the database module used. For example for mysql and postgres modules this is something like mysql://username:password@host:port/database. For dbtext module (which stores data in plaintext files) it is directory in which the database resides.
Default value is “mysql://openserro:openserro@localhost/openser”.
Example 1.1. db_url parameter usage
...
modparam("auth_db", "db_url", "dbdriver://username:password@dbhost/dbname")
...
This is the name of the column holding usernames. Default value is fine for most people. Use the parameter if you really need to change it.
Default value is “username”.
This is the name of the column holding domains of users. Default value is fine for most people. Use the parameter if you really need to change it.
Default value is “domain”.
This is the name of the column holding passwords. Passwords can be either stored as plain text or pre-calculated HA1 strings. HA1 strings are MD5 hashes of username, password, and realm. HA1 strings are more safe because the server doesn't need to know plaintext passwords and they cannot be obtained from HA1 strings.
Default value is “ha1”.
Example 1.4. password_column parameter usage
...
modparam("auth_db", "password_column", "password")
...
As described in the previous section this parameter contains name of
column holding pre-calculated HA1 string that were calculated including
the domain in the username. This parameter is used only when
calculate_ha1 is set to 0 and user agent send a
credentials containing the domain in the username.
Default value of the parameter is ha1b.
Example 1.5. password_column_2 parameter usage
...
modparam("auth_db", "password_column_2", "ha1_2")
...
This parameter tells the server whether it should use a pre-calculated HA1 string or plaintext passwords for authentification.
If the parameter is set to 0 and the username parameter of credentials contains also “@domain” (some user agents append the domain to the username parameter), then the server will use the HA1 values from the column specified in the “password_column_2” parameter. If the username parameter doesn't contain a domain, the server will use the HA1 values from the column given in the “password_column”parameter.
If the parameter is set to 1 then the HA1 value will be calculated from the column specified in the “password_column” parameter.
The “password_column_2”column contain also HA1 strings but they should be calculated including the domain in the username parameter (as opposed to password_column which (when containing HA1 strings) should always contains HA1 strings calculated without domain in username.
This ensures that the authentication will always work when using pre-calculated HA1 strings, not depending on the presence of the domain in username.
Default value of this parameter is 0.
If true (not 0), domain will be also used when looking up in the subscriber table. If you have a multi-domain setup, it is strongly recommended to turn on this parameter to avoid username overlapping between domains.
IMPORTANT: before turning on this parameter, be sure that the
domain column in subscriber
table is properly populated.
Default value is “0 (false)”.
This parameter specifies of credentials to be fetch from database when the authentication is performed. The loaded credentials will be stored in AVPs. If the AVP name is not specificaly given, it will be used a NAME AVP with the same name as the column name.
Parameter syntax:
load_credentials = credential (';' credential)*
credential = (avp_specification '=' column_name) | (column_name)
avp_specification = '$avp(' + 'i:'ID | 's:'NAME | alias + ')'
Default value of this parameter is “rpid”.
Example 1.8. load_credentials parameter usage
...
# load rpid column into $avp(i:123) and email_address column
# into $avp(s:email_address)
modparam("auth_db", "load_credentials", "$avp(i:123)=rpid;email_address")
...
Name alias: www_authorize(realm, table)
The function verifies credentials according to
RFC2617. If the
credentials are verified successfully then the function will succeed
and mark the credentials as authorized (marked credentials can be later
used by some other functions). If the function was unable to verify the
credentials for some reason then it will fail and the script should
call www_challenge which will
challenge the user again.
Negative codes may be interpreted as follows:
-1 (generic error) - some generic error occurred and no reply was sent out;
-2 (invalid password) - valid user, but wrong password;
-3 (invalid user) - authentication user does not exist.
Meaning of the parameters is as follows:
realm - Realm is a opaque string that the user agent should present to the user so he can decide what username and password to use. Usually this is domain of the host the server is running on.
It must not be empty string “”. In case of REGISTER requests To header field domain (e.g., variable $td) can be used (because this header field represents the user being registered), for all other messages From header field domain can be used (e.g., variable $fd).
The string may contain pseudo variables.
table - Table to be used to lookup usernames and passwords (usually subscribers table).
This function can be used from REQUEST_ROUTE.
Example 1.9. www_authorize usage
...
if (!www_authorize("kamailio.org", "subscriber")) {
www_challenge("kamailio.org", "1");
};
...
It is same function as www_authenticate(realm, table). This name is kept for backward compatibility, since it was named this way first time by it actually does user authentication.
Name alias: proxy_authorize(realm, table)
The function verifies credentials according to
RFC2617. If
the credentials are verified successfully then the function will
succeed and mark the credentials as authorized (marked credentials can
be later used by some other functions). If the function was unable to
verify the credentials for some reason then it will fail and
the script should call
proxy_challenge which will
challenge the user again.
Negative return codes have the same meaning as for www_authenticate().
Meaning of the parameters is as follows:
realm - Realm is a opaque string that the user agent should present to the user so he can decide what username and password to use. Usually this is domain of the host the server is running on.
It must not be empty string “”. Apart of a static strinh, typical value is From header field domain (e.g., variable $fd).
If an empty string “” is used then the server will generate it from the request. From header field domain will be used as realm.
The string may contain pseudo variables.
table - Table to be used to lookup usernames and passwords (usually subscribers table).
This function can be used from REQUEST_ROUTE.
Example 1.10. proxy_authorize usage
...
if (!proxy_authorize("$fd", "subscriber)) {
proxy_challenge("$fd", "1"); # Realm will be autogenerated
};
...