MIT Kerberos Documentation

krb5_mk_safe - Format a KRB-SAFE message.

krb5_error_code krb5_mk_safe(krb5_context context, krb5_auth_context auth_context, const krb5_data * userdata, krb5_data * outbuf, krb5_replay_data * outdata)

[in] context - Library context

[in] auth_context - Authentication context

[in] userdata - User data in the message

[out] outbuf - Formatted KRB-SAFE buffer

[out] outdata - Replay data. Specify NULL if not needed

  • 0 Success; otherwise - Kerberos error codes

This function creates an integrity protected KRB-SAFE message using data supplied by the application.

Fields in auth_context specify the checksum type, the keyblock that can be used to seed the checksum, full addresses (host and port) for the sender and receiver, and KRB5_AUTH_CONTEXT flags.

The local address in auth_context must be set, and is used to form the sender address used in the KRB-SAFE message. The remote address is optional; if specified, it will be used to form the receiver address used in the message.

If KRB5_AUTH_CONTEXT_DO_TIME flag is set in the auth_context , an entry describing the message is entered in the replay cache auth_context->rcache which enables the caller to detect if this message is reflected by an attacker. If KRB5_AUTH_CONTEXT_DO_TIME is not set, the replay cache is not used.

If either KRB5_AUTH_CONTEXT_DO_SEQUENCE or KRB5_AUTH_CONTEXT_RET_SEQUENCE is set, the auth_context local sequence number will be placed in outdata as its sequence number.

Use krb5_free_data_contents() to free outbuf when it is no longer needed.


The outdata argument is required if KRB5_AUTH_CONTEXT_RET_TIME or KRB5_AUTH_CONTEXT_RET_SEQUENCE flag is set in the auth_context .