KRB5_VERIFY_USER(3)

NAME
krb5_verify_user, krb5_verify_user_lrealm, krb5_verify_user_opt, krb5_verify_opt_init, krb5_verify_opt_alloc, krb5_verify_opt_free, krb5_verify_opt_set_ccache, krb5_verify_opt_set_flags, krb5_verify_opt_set_service, krb5_verify_opt_set_secure, krb5_verify_opt_set_keytab - Heimdal password verifying functions

LIBRARY
Kerberos 5 Library (libkrb5, -lkrb5)

SYNOPSIS
#include <krb5.h>
krb5_error_code
krb5_verify_user(krb5_context context, krb5_principal principal, krb5_ccache ccache, const char *password, krb5_boolean secure, const char *service);
krb5_error_code
krb5_verify_user_lrealm(krb5_context context, krb5_principal principal, krb5_ccache ccache, const char *password, krb5_boolean secure, const char *service);
void
krb5_verify_opt_init(krb5_verify_opt *opt);
void
krb5_verify_opt_alloc(krb5_verify_opt **opt);
void
krb5_verify_opt_free(krb5_verify_opt *opt);
void
krb5_verify_opt_set_ccache(krb5_verify_opt *opt, krb5_ccache ccache);
void
krb5_verify_opt_set_keytab(krb5_verify_opt *opt, krb5_keytab keytab);
void
krb5_verify_opt_set_secure(krb5_verify_opt *opt, krb5_boolean secure);
void
krb5_verify_opt_set_service(krb5_verify_opt *opt, const char *service);
void
krb5_verify_opt_set_flags(krb5_verify_opt *opt, unsigned int flags);
krb5_error_code
krb5_verify_user_opt(krb5_context context, krb5_principal principal, const char *password, krb5_verify_opt *opt);

DESCRIPTION
The krb5_verify_user function verifies the password supplied by a user. The principal whose password will be verified is specified in principal. New tickets will be obtained as a side-effect and stored in ccache (if NULL, the default ccache is used). krb5_verify_user() will call krb5_cc_initialize() on the given ccache, so ccache must only initialized with krb5_cc_resolve() or krb5_cc_gen_new(). If the password is not supplied in password (and is given as NULL) the user will be prompted for it. If secure the ticket will be verified against the locally stored service key service (by default ‘host’ if given as NULL ).

The krb5_verify_user_lrealm() function does the same, except that it ignores the realm in principal and tries all the local realms (see krb5.conf(5)). After a successful return, the principal is set to the authenticated realm. If the call fails, the principal will not be meaningful, and should only be freed with krb5_free_principal(3).

krb5_verify_opt_alloc() and krb5_verify_opt_free() allocates and frees a krb5_verify_opt. You should use the the alloc and free function instead of allocation the structure yourself, this is because in a future release the structure wont be exported.

krb5_verify_opt_init() resets all opt to default values.

None of the krb5_verify_opt_set function makes a copy of the data structure that they are called with. It's up the caller to free them after the krb5_verify_user_opt() is called.

krb5_verify_opt_set_ccache() sets the ccache that user of opt will use. If not set, the default credential cache will be used.

krb5_verify_opt_set_keytab() sets the keytab that user of opt will use. If not set, the default keytab will be used.

krb5_verify_opt_set_secure() if secure if true, the password verification will require that the ticket will be verified against the locally stored service key. If not set, default value is true.

krb5_verify_opt_set_service() sets the service principal that user of opt will use. If not set, the ‘host’ service will be used.

krb5_verify_opt_set_flags() sets flags that user of opt will use. If the flag KRB5_VERIFY_LREALMS is used, the principal will be modified like krb5_verify_user_lrealm() modifies it.

krb5_verify_user_opt() function verifies the password supplied by a user. The principal whose password will be verified is specified in principal. Options the to the verification process is pass in in opt.

EXAMPLES
Here is a example program that verifies a password. it uses the ‘host/`hostname`’ service principal in krb5.keytab.

    #include <krb5.h>

    int
    main(int argc, char **argv)
    {
        char *user;
        krb5_error_code error;
        krb5_principal princ;
        krb5_context context;

        if (argc != 2)
    	errx(1, "usage: verify_passwd <principal-name>");

        user = argv[1];

        if (krb5_init_context(&context) < 0)
    	errx(1, "krb5_init_context");

        if ((error = krb5_parse_name(context, user, &princ)) != 0)
    	krb5_err(context, 1, error, "krb5_parse_name");

        error = krb5_verify_user(context, princ, NULL, NULL, TRUE, NULL);
        if (error)
            krb5_err(context, 1, error, "krb5_verify_user");

        return 0;
    }

SEE ALSO
krb5_cc_gen_new(3), krb5_cc_initialize(3), krb5_cc_resolve(3), krb5_err(3), krb5_free_principal(3), krb5_init_context(3), krb5_kt_default(3), krb5.conf(5)