NAME
auth_generic - Generic authentication request
SYNOPSIS
#include <courierauth.h>
int rc=auth_generic(const char *service, const char *authtype,
const char *authdata,
int (*callback_func) (struct authinfo *, void *),
void *callback_arg);
DESCRIPTION
auth_generic processes a generic authentication request. You do not
want to use this function. You really want to use auth_login(3)[1].
service specifies which so-called "service" is being authenticated;
like “imap” or “pop3”. service may or may not be used by the Courier
authentication library´s configured back-end module.
authtype specifies the format of the authentication request. Three
authentication formats are defined in courierauth.h:
AUTHTYPE_LOGIN
authdata contains the following string: “userid\npassword\n”. That
is, the userid being authenticated, an ASCII newline character, the
password, and a second newline character.
AUTHTYPE_CRAMMD5 or AUTHTYPE_CRAMSHA1
This format is used with CRAM-MD5 or CRAM-SHA1. authdata contains
the following string: “challenge\nresponse\n”. challenge is the
base64-encoded challenge, which is followed by an ASCII newline
character. response is a base64-encoded string that´s followed by
a second newline character. The base64-encoded string consists of
the responding userid, a space character, then the response to the
challenge expressed as hexadecimal digits.
RETURNS
callback_func will be invoked if auth_generic succeeds, and
callback_func´s return value becomes the return value from auth_generic
(which should be 0, by convention). callback_func will not be invoked
if an error occurs, which is reported by a non-zero return value from
auth_generic. By convention, a positive return value indicates an
internal, temporary failure, such as the authentication daemon process
not running; a negative return value indicates that this request was
processed, but it failed.
The second argument to callback_func will be callback_arg, which is not
interpreted by this function in any way. The first argument will be a
pointer to the following structure:
Example 1. struct authinfo
struct authinfo {
const char *sysusername;
const uid_t *sysuserid;
gid_t sysgroupid;
const char *homedir;
const char *address;
const char *fullname;
const char *maildir;
const char *quota;
const char *passwd;
const char *clearpasswd;
const char *options;
} ;
Description of the above fields:
address
The authenticated login ID.
sysusername
The authenticated account´s userid and groupid can be looked up in
the password file using address. If this field is NULL, obtain the
userid and the groupid from sysuserid and sysgroupid.
sysuserid
sysuserid may be NULL if sysusername is initialized, otherwise it´s
a pointer to the account´s numeric userid.
sysgroupid
Account´s numeric groupid. sysgroupid is only used when
sysusername is NULL.
fullname
This is the account´s full name. This field is optional, it may be
NULL.
homedir
The account´s home directory. This field cannot be NULL.
maildir
The pathname to the account´s mailbox. This field is optional, it
can be NULL in which case the default location is assumed.
quota
Optional maildir quota on the account´s mailbox (and NULL if no
quota is set).
passwd
The account´s encrypted password, if available. If the account has
a cleartext password defined, this field can be set to NULL. The
encrypted password can take several formats:
· A traditional triple-DES crypted password, or a MD5+salt-hashed
password, as used in Linux.
· “{MD5}” followed by a base64-encoded MD5 hash of the password.
· “{SHA}” followed by a base64-encoded SHA1 hash of the
password.
clearpasswd
The account´s cleartext password, if available. If the account has
an encrypted password defined, this field can be set to NULL.
options
A comma-separated list of miscellaneous account options. See below
for more information.
Account options
Depending on the configuration of the Courier authentication library,
accounts may have individual options associated with them. If the
authentication library configuration does not implement account
options, the option string will be NULL. Otherwise it will be a
comma-separated list of “option=value” settings.
Note
This is the account option implementation that´s used by Courier,
Courier-IMAP, and SqWebMail packages. Some of the following information
is obviously not applicable for a particular package. The inapplicable
bits should be obvious.
The following options are recognized by the various Courier packages:
Note
The application is responsible for enforcing all the “disabled” option.
An authentication request for service “imap”, for example, will succeed
provided that the userid and the password are valid, even if
“disableimap=1” is set. The application´s callback_func should check
for this condition, and return a negative return code.
disableimap=n
If "n" is 1, IMAP access to this account should be disabled.
disablepop3=n
If "n" is 1, POP3 access to this account should be disabled.
disablewebmail=n
If "n" is 1, webmail access to this account should be disabled.
disableshared=n
If "n" is 1, this account should not have access to shared folders
or be able to share its own folders with other people.
group=name
This account is a member of access group name. Instead of granting
access rights on individual mail folders to individual accounts,
the access rights can be granted to an access group “name”, and all
members of this group get the specified access rights.
The access group name “administrators” is a reserved group. All
accounts in the administrators group automatically receive all
rights to all accessible folders.
Note
This option may be specified multiple times to specify that the
account belongs to multiple account groups.
sharedgroup=name
Append "name" to the name of the top level virtual shared folder
index file. This setting restricts which virtual shared folders
this account could possibly access (and that´s on top of whatever
else the access control lists say). See the virtual shared folder
documentation for more information.
For technical reasons, group names may not include comma, tab, "/"
or "|" characters.
SEE ALSO
authlib(3)[2], auth_login(3)[1], auth_getuserinfo(3)[3],
auth_enumerate(3)[4], auth_passwd(3)[5], auth_getoption(3)[6].
NOTES
1. auth_login(3)
auth_login.html
2. authlib(3)
authlib.html
3. auth_getuserinfo(3)
auth_getuserinfo.html
4. auth_enumerate(3)
auth_enumerate.html
5. auth_passwd(3)
auth_passwd.html
6. auth_getoption(3)
auth_getoption.html