KRB5\_VERIFY\_INIT\_CREDS(3) Library Functions Manual KRB5\_VERIFY\_INIT\_CREDS(3)

# [NAME](#NAME)

`krb5_verify_init_creds_opt_init`, `krb5_verify_init_creds_opt_set_ap_req_nofail`, `krb5_verify_init_creds` — verifies a credential cache is correct by using a local keytab

# [LIBRARY](#LIBRARY)

Kerberos 5 Library (libkrb5, -lkrb5)

# [SYNOPSIS](#SYNOPSIS)

`#include <krb5.h>`

`struct krb5_verify_init_creds_opt;`  
`void`  
`krb5_verify_init_creds_opt_init`(`krb5_verify_init_creds_opt *options`);

`void`  
`krb5_verify_init_creds_opt_set_ap_req_nofail`(`krb5_verify_init_creds_opt *options`, `int ap_req_nofail`);

`krb5_error_code`  
`krb5_verify_init_creds`(`krb5_context context`, `krb5_creds *creds`, `krb5_principal ap_req_server`, `krb5_ccache *ccache`, `krb5_verify_init_creds_opt *options`);

# [DESCRIPTION](#DESCRIPTION)

The `krb5_verify_init_creds` function verifies the initial tickets with the local keytab to make sure the response of the KDC was spoof-ed.

`krb5_verify_init_creds` will use principal `ap_req_server` from the local keytab, if `NULL` is passed in, the code will guess the local hostname and use that to form host/hostname/GUESSED-REALM-FOR-HOSTNAME. `creds` is the credential that `krb5_verify_init_creds` should verify. If `ccache` is given [`krb5_verify_init_creds`](#krb5_verify_init_creds)() stores all credentials it fetched from the KDC there, otherwise it will use a memory credential cache that is destroyed when done.

[`krb5_verify_init_creds_opt_init`](#krb5_verify_init_creds_opt_init)() cleans the the structure, must be used before trying to pass it in to `krb5_verify_init_creds`().

[`krb5_verify_init_creds_opt_set_ap_req_nofail`](#krb5_verify_init_creds_opt_set_ap_req_nofail)() controls controls the behavior if `ap_req_server` doesn't exists in the local keytab or in the KDC's database, if it's true, the error will be ignored. Note that this use is possible insecure.

# [SEE ALSO](#SEE_ALSO)

[krb5(3)](/man/os/heimdal/krb5.3), [krb5\_get\_init\_creds(3)](/man/os/heimdal/krb5_get_init_creds.3), [krb5\_verify\_user(3)](/man/os/heimdal/krb5_verify_user.3), [krb5.conf(5)](/man/os/heimdal/krb5.conf.5)

May 1, 2006 HEIMDAL

---

Document: krb5_verify_init_creds_opt_init(3) from heimdal 7.8.0-r52 (Chainguard OS)
Source: https://github.com/heimdal/heimdal