Problem - Kevin Tafuro

each of these pieces of information in a single structure rather than adding several
additional arguments to our authentication functions.
#include
typedef struct {
krb5_context ctx;
krb5_auth_context auth_ctx;
krb5_ticket *ticket;
} spc_krb5bundle_t;
On the client side, only the ctx and auth_ctx fields will be initialized. On the server
side, all three fields will be initialized. Before passing an spc_krb5bundle_t object to
either spc_krb5_client( ) or spc_krb5_server( ), you must ensure that auth_ctx and
ticket are initialized to NULL. If the ctx field is not NULL, it should be a valid krb5_
context object, which will be used instead of creating a new one.
Both the client and the server must be able to handle using Kerberos authentication.
The code required for each side of the connection is very similar. On the client side,
spc_krb5_client( ) will attempt to authenticate with the server. The code assumes
that the user has already obtained a ticket-granting ticket from the appropriate Key
Distribution Center (KDC), and that a credentials cache exists.
The function spc_krb5_client( ) has the following signature:
krb5_error_code spc_krb5_client(int sockfd, spc_krb5bundle_t *bundle,
char *service, char *host, char *version);
This function has the following arguments:
sockfd
Socket descriptor over which the authentication should be performed. The connection
to the server should already be established, and the socket should be in
blocking mode.
bundle
spc_krb5bundle_t object that will be loaded with information if the authentication
with the server is successful. Before calling spc_krb5_client( ), you should
be sure to zero the contents of this structure. If the structure contains a pointer
to a Kerberos context object, spc_krb5_client( ) will use it instead of creating a
new one.
service
Name component of the server’s principal. It is combined with the server’s hostname
or instance to build the principal for the server. The server’s principal will
be of the form service/host@REALM. The realm is assumed to be the user’s default
realm.
host
Hostname of the server. It is used as the instance component of the server’s principal.
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Authenticating with Kerberos | 415