2 * lib/krb5/krb/gen_subkey.c
4 * Copyright 1991 by the Massachusetts Institute of Technology.
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8 * require a specific license from the United States Government.
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13 * distribute this software and its documentation for any purpose and
14 * without fee is hereby granted, provided that the above copyright
15 * notice appear in all copies and that both that copyright notice and
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17 * the name of M.I.T. not be used in advertising or publicity pertaining
18 * to distribution of the software without specific, written prior
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24 * Routine to automatically generate a subsession key based on an input key.
30 krb5_generate_subkey(context, key, subkey)
32 const krb5_keyblock *key;
33 krb5_keyblock **subkey;
35 krb5_pointer random_state;
36 krb5_encrypt_block eblock;
37 krb5_error_code retval;
39 if (!valid_keytype(key->keytype))
40 return KRB5_PROG_KEYTYPE_NOSUPP;
42 krb5_use_keytype(context, &eblock, key->keytype);
44 if (retval = krb5_init_random_key(context, &eblock, key, &random_state))
46 *subkey = (krb5_keyblock *)malloc(sizeof(**subkey));
48 (void) krb5_finish_random_key(context, &eblock, &random_state);
52 if (retval = krb5_random_key(context, &eblock, random_state, subkey)) {
53 (void) krb5_finish_random_key(context, &eblock, &random_state);
57 /* ignore the error if any, since we've already gotten the key out */
58 (void) krb5_finish_random_key(context, &eblock, &random_state);