4.2.1 Data Types

Data Type: mu_auth_fp

This is a pointer to authentication or authorization data. It is defined as follows:

typedef int (*mu_auth_fp) (struct mu_auth_data **return_data, void *key, void *func_data, void *call_data);

Its arguments are:

return_data

Upon successful return authorization handler leaves in this memory location a pointer to the filled mu_auth_data structure with the user's information.

For authentication handlers this argument is always NULL and should be ignored.

key

The search key value. Its actual type depends upon type of the handler.

For authorization handlers it is const char* if the handler is called by mu_get_auth_by_name() and uid_t * if it is called by mu_get_auth_by_uid().

For authentication handlers it is always struct mu_auth_data* representing the user's data obtained by a previous call to a mu_get_auth_by_... function.

func_data

Any data associated with this handler.

call_data

Any call specific data. This argument is not used at the moment.

Data Type: mu_auth_data

The mu_auth_data is used to return the information about the user. It is similar to system struct passwd, except that it is more mailutils-specific. Its definition is:

struct mu_auth_data { /* These are from struct passwd */ char *name; /* user name */ char *passwd; /* user password */ uid_t uid; /* user id */ gid_t gid; /* group id */ char *gecos; /* real name */ char *dir; /* home directory */ char *shell; /* shell program */ /* */ char *mailbox; /* Path to the user's system mailbox */ int change_uid; /* Should the uid be changed? */ };

Data Type: mu_auth_module

The mu_auth_module structure contains full information about a libmuauth module. It is declared as follows:

struct mu_auth_module { char *name; /* Module name */ struct argp *argp; /* Corresponding argp structure */ mu_auth_fp authenticate; /* Authentication function ... */ void *authenticate_data; /* ... and its specific data */ mu_auth_fp auth_by_name; /* Get user info by user name */ void *auth_by_name_data; /* ... and its specific data */ mu_auth_fp auth_by_uid; /* Get user info by user id */ void *auth_by_uid_data; /* ... and its specific data */ };