NAME

       nfs4_uid_to_name,    nfs4_gid_to_name,    nfs4_name_to_uid,   nfs4_name_to_gid,   nfs4_init_name_mapping,
       nfs4_get_default_domain,  nfs4_gss_princ_to_ids,  nfs4_gss_princ_to_grouplist,  nfs4_gss_princ_to_ids_ex,
       nfs4_gss_princ_to_grouplist_ex, nfs4_set_debug - ID mapping routines used for NFSv4

SYNOPSIS

       #include <nfs4_idmap.h>

       int nfs4_init_name_mapping(char *conffile);

       int nfs4_get_default_domain(char *server, char *domain, size_t len);

       int nfs4_uid_to_name(uid_t uid, char *domain, char *name, size_t len);

       int nfs4_uid_to_owner(uid_t uid, char *domain, char *name, size_t len);

       int nfs4_gid_to_name(gid_t gid, char *domain, char *name, size_t len);

       int nfs4_gid_to_owner(gid_t gid, char *domain, char *name, size_t len);

       int nfs4_name_to_uid(char *name, uid_t *uid);

       int nfs4_name_to_gid(char *name, gid_t *gid);

       int nfs4_owner_to_uid(char *name, uid_t *uid);

       int nfs4_owner_to_gid(char *name, gid_t *gid);

       int nfs4_gss_princ_to_ids(char *secname, char *princ, uid_t *uid, gid_t *gid);

       int nfs4_gss_princ_to_grouplist(char *secname, char *princ, gid_t *groups, int *ngroups);

       int  nfs4_gss_princ_to_ids_ex(char  *secname,  char  *princ, uid_t *uid, gid_t *gid, extra_mapping_params
       **ex);

       int  nfs4_gss_princ_to_grouplist_ex(char  *secname,   char   *princ,   gid_t   *groups,   int   *ngroups,
       extra_mapping_params **ex);

       void nfs4_set_debug(int dbg_level, void (*logger)(const char *, ...));

DESCRIPTION

       NFSv4  uses  names of the form user@domain.  To write code that helps the kernel map uid's (as rpc.idmapd
       does) or that processes NFSv4 ACLs, you need to be able to convert between NFSv4 names and local uids and
       gids.

       The  nfs4_uid_to_name()  and  nfs4_gid_to_name()  functions,  given  uid  or  gid  and domain (as a null-
       terminated string), write the corresponding nfsv4 name into the buffer provided in name, which must be of
       length at least len.

       The  nfs4_uid_to_owner() and nfs4_gid_to_group_owner() functions, given uid or gid and domain (as a null-
       terminated string), write the corresponding nfsv4 name into the buffer provided in name, which must be of
       length  at  least  len.   If there is no valid mapping from uid or gid to name, then the numerical string
       representing uid or gid is returned instead.

       The nfs4_name_to_uid() and nfs4_name_to_gid() functions, given name (as a null-terminated string), return
       the corresponding uid or gid in the second parameter.

       The  nfs4_owner_to_uid()  and  nfs4_group_owner_to_gid()  functions,  given  name  (as  a null-terminated
       string), return the corresponding uid or gid in the second parameter.  If there is no valid mapping  from
       name to uid or gid the value for the user or group "nobody" will be returned instead.

       The  nfs4_init_name_mapping()  function  must  be  called  before using any of these functions.  It reads
       defaults from the configuration file at the provided path, usually "etc/idmapd.conf".

       The domain argument to the id-to-name functions is there to provide a hint to the name mapper in the case
       where  an  id  might be mapped to names in multiple domains.  In most cases, this argument should just be
       the name returned in the domain argument to nfs4_get_default_domain() which should be called with  server
       set  to NULL.  The domain should be a buffer of length len.  The constant NFS4_MAX_DOMAIN_LEN may be used
       to determine a reasonable value for that length.

       The function nfs4_get_grouplist(), given a name, fills the provided array  groups  with  up  to  *ngroups
       group  IDs corresponding to which the user name belongs to, setting *ngroups to the actual number of such
       groups.  If the user belongs to more than *ngroups groups, then an  error  is  returned  and  the  actual
       number of groups is stored in *ngroups.

       Functions   nfs4_gss_princ_to_ids(),   nfs4_gss_princ_to_grouplist(),   nfs4_gss_princ_to_ids_ex(),   and
       nfs4_gss_princ_to_grouplist_ex() are  used  to  convert  from  a  gss  principal  name  (as  returned  by
       gss_display_name()) to a uid and gid, or list of gids.

       Finally,  nfs4_set_debug()  allows  the  application  to set a debugging level to produce extra debugging
       information from within the library.  The optional  logger  function  specifies  an  alternative  logging
       function to call for the debug messages rather than the default internal function within the library.

RETURN VALUE

       All functions return 0 or, in the case of error, -ERRNO.

                                                   2004-08-05                                nfs4_uid_to_name(3)