NAME
krb5_get_default_principal, krb5_principal, krb5_build_principal,
krb5_build_principal_ext, krb5_build_principal_va,
krb5_build_principal_va_ext, krb5_copy_principal, krb5_free_principal,
krb5_make_principal, krb5_parse_name, krb5_parse_name_flags,
krb5_parse_nametype, krb5_princ_set_realm, krb5_principal_compare,
krb5_principal_compare_any_realm, krb5_principal_get_comp_string,
krb5_principal_get_realm, krb5_principal_get_type, krb5_principal_match,
krb5_principal_set_type, krb5_realm_compare, krb5_sname_to_principal,
krb5_sock_to_principal, krb5_unparse_name, krb5_unparse_name_flags,
krb5_unparse_name_fixed, krb5_unparse_name_fixed_flags,
krb5_unparse_name_fixed_short, krb5_unparse_name_short - Kerberos 5
principal handling functions
LIBRARY
Kerberos 5 Library (libkrb5, -lkrb5)
SYNOPSIS
#include <krb5.h>
krb5_principal;
void
krb5_free_principal(krb5_context context, krb5_principal principal);
krb5_error_code
krb5_parse_name(krb5_context context, const char *name,
krb5_principal *principal);
krb5_error_code
krb5_parse_name_flags(krb5_context context, const char *name, int flags,
krb5_principal *principal);
krb5_error_code
krb5_unparse_name(krb5_context context, krb5_const_principal principal,
char **name);
krb5_error_code
krb5_unparse_name_flags(krb5_context context,
krb5_const_principal principal, int flags, char **name);
krb5_error_code
krb5_unparse_name_fixed(krb5_context context,
krb5_const_principal principal, char *name, size_t len);
krb5_error_code
krb5_unparse_name_fixed_flags(krb5_context context,
krb5_const_principal principal, int flags, char *name,
size_t len);
krb5_error_code
krb5_unparse_name_short(krb5_context context,
krb5_const_principal principal, char **name);
krb5_error_code
krb5_unparse_name_fixed_short(krb5_context context,
krb5_const_principal principal, char *name, size_t len);
void
krb5_princ_set_realm(krb5_context context, krb5_principal principal,
krb5_realm *realm);
krb5_error_code
krb5_build_principal(krb5_context context, krb5_principal *principal,
int rlen, krb5_const_realm realm, ...);
krb5_error_code
krb5_build_principal_va(krb5_context context, krb5_principal *principal,
int rlen, krb5_const_realm realm, va_list ap);
krb5_error_code
krb5_build_principal_ext(krb5_context context, krb5_principal *principal,
int rlen, krb5_const_realm realm, ...);
krb5_error_code
krb5_build_principal_va_ext(krb5_context context,
krb5_principal *principal, int rlen, krb5_const_realm realm,
va_list ap);
krb5_error_code
krb5_make_principal(krb5_context context, krb5_principal *principal,
krb5_const_realm realm, ...);
krb5_error_code
krb5_copy_principal(krb5_context context, krb5_const_principal inprinc,
krb5_principal *outprinc);
krb5_boolean
krb5_principal_compare(krb5_context context, krb5_const_principal princ1,
krb5_const_principal princ2);
krb5_boolean
krb5_principal_compare_any_realm(krb5_context context,
krb5_const_principal princ1, krb5_const_principal princ2);
const char *
krb5_principal_get_comp_string(krb5_context context,
krb5_const_principal principal, unsigned int component);
const char *
krb5_principal_get_realm(krb5_context context,
krb5_const_principal principal);
int
krb5_principal_get_type(krb5_context context,
krb5_const_principal principal);
krb5_boolean
krb5_principal_match(krb5_context context,
krb5_const_principal principal, krb5_const_principal pattern);
void
krb5_principal_set_type(krb5_context context, krb5_principal principal,
int type);
krb5_boolean
krb5_realm_compare(krb5_context context, krb5_const_principal princ1,
krb5_const_principal princ2);
krb5_error_code
krb5_sname_to_principal(krb5_context context, const char *hostname,
const char *sname, int32_t type, krb5_principal *ret_princ);
krb5_error_code
krb5_sock_to_principal(krb5_context context, int socket,
const char *sname, int32_t type, krb5_principal *principal);
krb5_error_code
krb5_get_default_principal(krb5_context context, krb5_principal *princ);
krb5_error_code
krb5_parse_nametype(krb5_context context, const char *str,
int32_t *type);
DESCRIPTION
krb5_principal holds the name of a user or service in Kerberos.
A principal has two parts, a PrincipalName and a realm. The
PrincipalName consists of one or more components. In printed form, the
components are separated by /. The PrincipalName also has a name-type.
Examples of a principal are nisse/root@EXAMPLE.COM and
host/datan.kth.se@KTH.SE. krb5_parse_name() and krb5_parse_name_flags()
passes a principal name in name to the kerberos principal structure.
krb5_parse_name_flags() takes an extra flags argument the following flags
can be passed in
KRB5_PRINCIPAL_PARSE_NO_REALM
requries the input string to be without a realm, and no realm is
stored in the principal return argument.
KRB5_PRINCIPAL_PARSE_REQUIRE_REALM
requries the input string to with a realm.
krb5_unparse_name() and krb5_unparse_name_flags() prints the principal
princ to the string name. name should be freed with free(3). To the
flags argument the following flags can be passed in
KRB5_PRINCIPAL_UNPARSE_SHORT
no realm if the realm is one of the local realms.
KRB5_PRINCIPAL_UNPARSE_NO_REALM
never include any realm in the principal name.
KRB5_PRINCIPAL_UNPARSE_DISPLAY
don’t quote
On failure name is set to NULL. krb5_unparse_name_fixed() and
krb5_unparse_name_fixed_flags() behaves just like krb5_unparse(), but
instead unparses the principal into a fixed size buffer.
krb5_unparse_name_short() just returns the principal without the realm if
the principal is in the default realm. If the principal isn’t, the full
name is returned. krb5_unparse_name_fixed_short() works just like
krb5_unparse_name_short() but on a fixed size buffer.
krb5_build_principal() builds a principal from the realm realm that has
the length rlen. The following arguments form the components of the
principal. The list of components is terminated with NULL.
krb5_build_principal_va() works like krb5_build_principal() using vargs.
krb5_build_principal_ext() and krb5_build_principal_va_ext() take a list
of length-value pairs, the list is terminated with a zero length.
krb5_make_principal() works the same way as krb5_build_principal(),
except it figures out the length of the realm itself.
krb5_copy_principal() makes a copy of a principal. The copy needs to be
freed with krb5_free_principal().
krb5_principal_compare() compares the two principals, including realm of
the principals and returns TRUE if they are the same and FALSE if not.
krb5_principal_compare_any_realm() works the same way as
krb5_principal_compare() but doesn’t compare the realm component of the
principal.
krb5_realm_compare() compares the realms of the two principals and
returns TRUE is they are the same, and FALSE if not.
krb5_principal_match() matches a principal against a pattern. The
pattern is a globbing expression, where each component (separated by /)
is matched against the corresponding component of the principal.
The krb5_principal_get_realm() and krb5_principal_get_comp_string()
functions return parts of the principal, either the realm or a specific
component. Both functions return string pointers to data inside the
principal, so they are valid only as long as the principal exists.
The component argument to krb5_principal_get_comp_string() is the index
of the component to return, from zero to the total number of components
minus one. If the index is out of range NULL is returned.
krb5_principal_get_realm() and krb5_principal_get_comp_string() are
replacements for krb5_princ_component() and related macros, described as
internal in the MIT API specification. Unlike the macros, these
functions return strings, not krb5_data. A reason to return krb5_data
was that it was believed that principal components could contain binary
data, but this belief was unfounded, and it has been decided that
principal components are infact UTF8, so it’s safe to use zero terminated
strings.
It’s generally not necessary to look at the components of a principal.
krb5_principal_get_type() and krb5_principal_set_type() get and sets the
name type for a principal. Name type handling is tricky and not often
needed, don’t use this unless you know what you do.
krb5_sname_to_principal() and krb5_sock_to_principal() are for easy
creation of “service” principals that can, for instance, be used to
lookup a key in a keytab. For both functions the sname parameter will be
used for the first component of the created principal. If sname is NULL,
“host” will be used instead.
krb5_sname_to_principal() will use the passed hostname for the second
component. If type is KRB5_NT_SRV_HST this name will be looked up with
gethostbyname(). If hostname is NULL, the local hostname will be used.
krb5_sock_to_principal() will use the “sockname” of the passed socket,
which should be a bound AF_INET or AF_INET6 socket. There must be a
mapping between the address and “sockname”. The function may try to
resolve the name in DNS.
krb5_get_default_principal() tries to find out what’s a reasonable
default principal by looking at the environment it is running in.
krb5_parse_nametype() parses and returns the name type integer value in
type. On failure the function returns an error code and set the error
string.
SEE ALSO
krb5_425_conv_principal(3), krb5_config(3), krb5.conf(5)
BUGS
You can not have a NUL in a component in some of the variable argument
functions above. Until someone can give a good example of where it would
be a good idea to have NUL’s in a component, this will not be fixed.