Linux Certif

Toute la documentation sur la certification Linux LPI

krb5_krbhst_next_as_string

BSD mandoc
HEIMDAL

NAME

krb5_krbhst_init krb5_krbhst_init_flags krb5_krbhst_next krb5_krbhst_next_as_string krb5_krbhst_reset krb5_krbhst_free krb5_krbhst_format_string krb5_krbhst_get_addrinfo - lookup Kerberos KDC hosts

LIBRARY

Kerberos 5 Library (libkrb5, -lkrb5)

SYNOPSIS

In krb5.h Ft krb5_error_code Fn krb5_krbhst_init krb5_context context const char *realm unsigned int type krb5_krbhst_handle *handle Ft krb5_error_code Fn krb5_krbhst_init_flags krb5_context context const char *realm unsigned int type int flags krb5_krbhst_handle *handle Ft krb5_error_code Fn krb5_krbhst_next krb5_context context krb5_krbhst_handle handle krb5_krbhst_info **host Ft krb5_error_code Fn krb5_krbhst_next_as_string krb5_context context krb5_krbhst_handle handle char *hostname size_t hostlen Ft void Fn krb5_krbhst_reset krb5_context context krb5_krbhst_handle handle Ft void Fn krb5_krbhst_free krb5_context context krb5_krbhst_handle handle Ft krb5_error_code Fn krb5_krbhst_format_string krb5_context context const krb5_krbhst_info *host char *hostname size_t hostlen Ft krb5_error_code Fn krb5_krbhst_get_addrinfo krb5_context context krb5_krbhst_info *host struct addrinfo **ai

DESCRIPTION

These functions are used to sequence through all Kerberos hosts of a particular realm and service. The service type can be the KDCs, the administrative servers, the password changing servers, or the servers for Kerberos 4 ticket conversion.

First a handle to a particular service is obtained by calling Fn krb5_krbhst_init (or Fn krb5_krbhst_init_flags ) with the Fa realm of interest and the type of service to lookup. The Fa type can be one of:

KRB5_KRBHST_KDC

KRB5_KRBHST_ADMIN

KRB5_KRBHST_CHANGEPW

KRB5_KRBHST_KRB524

The Fa handle is returned to the caller, and should be passed to the other functions.

The Fa flag argument to krb5_krbhst_init_flags is the same flags as Fn krb5_send_to_kdc_flags uses. Possible values are:

KRB5_KRBHST_FLAGS_MASTER

only talk to master (readwrite) KDC

KRB5_KRBHST_FLAGS_LARGE_MSG

this is a large message, so use transport that can handle that.

For each call to Fn krb5_krbhst_next information on a new host is returned. The former function returns in Fa host a pointer to a structure containing information about the host, such as protocol, hostname, and port:

 typedef struct krb5_krbhst_info {
     enum { KRB5_KRBHST_UDP,
            KRB5_KRBHST_TCP,
            KRB5_KRBHST_HTTP } proto;
     unsigned short port;
     struct addrinfo *ai;
     struct krb5_krbhst_info *next;
     char hostname[1];
 } krb5_krbhst_info;
 

The related function, Fn krb5_krbhst_next_as_string , return the same information as a URL-like string.

When there are no more hosts, these functions return KRB5_KDC_UNREACH

To re-iterate over all hosts, call Fn krb5_krbhst_reset and the next call to Fn krb5_krbhst_next will return the first host.

When done with the handle, Fn krb5_krbhst_free should be called.

To use a krb5_krbhst_info there are two functions: Fn krb5_krbhst_format_string that will return a printable representation of that struct and Fn krb5_krbhst_get_addrinfo that will return a struct addrinfo that can then be used for communicating with the server mentioned.

EXAMPLES

The following code will print the KDCs of the realm ``MY.REALM''

 krb5_krbhst_handle handle;
 char host[MAXHOSTNAMELEN];
 krb5_krbhst_init(context, "MY.REALM", KRB5_KRBHST_KDC, &handle);
 while(krb5_krbhst_next_as_string(context, handle,
                                  host, sizeof(host)) == 0)
     printf("%s\n", host);
 krb5_krbhst_free(context, handle);
 

SEE ALSO

getaddrinfo(3), krb5_get_krbhst3, krb5_send_to_kdc_flags3

HISTORY

These functions first appeared in Heimdal 0.3g.