/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* tests/adata.c - Test harness for KDC authorization data */
/*
* Copyright (C) 2014 by the Massachusetts Institute of Technology.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Usage: ./adata [-c ccname] [-p clientprinc] serviceprinc
* [ad-type ad-contents ...]
*
* This program acquires credentials for the specified service principal, using
* the specified or default ccache, possibly including requested authdata. The
* resulting ticket is decrypted using the default keytab, and the authdata in
* the ticket are displayed to stdout.
*
* In the requested authdata types, the type may be prefixed with '?' for an
* AD-IF-RELEVANT container, '!' for an AD-MANDATORY-FOR-KDC container, or '^'
* for an AD-KDC-ISSUED container checksummed with a random AES256 key.
* Multiple prefixes may be specified for nested container.
*
* In the output, authdata containers will be flattened and displayed with the
* above prefixes or '+' for an AD-CAMMAC container. AD-KDC-ISSUED and
* AD-CAMMAC containers will be verified with the appropriate key. Nested
* containers only display the prefix for the innermost container.
*/
#include <k5-int.h>
#include <ctype.h>
static krb5_context ctx;
static void display_authdata_list(krb5_authdata **list, krb5_keyblock *skey,
krb5_keyblock *tktkey, char prefix_byte,
krb5_boolean pac_expected);
static void
check(krb5_error_code code)
{
const char *errmsg;
if (code) {
errmsg = krb5_get_error_message(ctx, code);
fprintf(stderr, "%s\n", errmsg);
krb5_free_error_message(ctx, errmsg);
exit(1);
}
}
static krb5_authdatatype
get_type_for_prefix(int prefix_byte)
{
if (prefix_byte == '?')
return KRB5_AUTHDATA_IF_RELEVANT;
if (prefix_byte == '!')
return KRB5_AUTHDATA_MANDATORY_FOR_KDC;
if (prefix_byte == '^')
return KRB5_AUTHDATA_KDC_ISSUED;
if (prefix_byte == '+')
return KRB5_AUTHDATA_CAMMAC;
abort();
}
static int
get_prefix_byte(krb5_authdata *ad)
{
if (ad->ad_type == KRB5_AUTHDATA_IF_RELEVANT)
return '?';
if (ad->ad_type == KRB5_AUTHDATA_MANDATORY_FOR_KDC)
return '!';
if (ad->ad_type == KRB5_AUTHDATA_KDC_ISSUED)
return '^';
if (ad->ad_type == KRB5_AUTHDATA_CAMMAC)
return '+';
abort();
}
/* Construct a container of type ad_type for the single authdata element
* content. For KDC-ISSUED containers, use a random checksum key. */
static krb5_authdata *
make_container(krb5_authdatatype ad_type, krb5_authdata *content)
{
krb5_authdata *list[2], **enclist, *ad;
krb5_keyblock kb;
list[0] = content;
list[1] = NULL;
if (ad_type == KRB5_AUTHDATA_KDC_ISSUED) {
check(krb5_c_make_random_key(ctx, ENCTYPE_AES256_CTS_HMAC_SHA1_96,
&kb));
check(krb5_make_authdata_kdc_issued(ctx, &kb, NULL, list, &enclist));
krb5_free_keyblock_contents(ctx, &kb);
} else {
check(krb5_encode_authdata_container(ctx, ad_type, list, &enclist));
}
/* Grab the first element from the encoded list and free the array. */
ad = enclist[0];
free(enclist);
return ad;
}
/* Parse typestr and contents into an authdata element. */
static krb5_authdata *
make_authdata(const char *typestr, const char *contents)
{
krb5_authdata *inner_ad, *ad;
if (*typestr == '?' || *typestr == '!' || *typestr == '^') {
inner_ad = make_authdata(typestr + 1, contents);
ad = make_container(get_type_for_prefix(*typestr), inner_ad);
free(inner_ad->contents);
free(inner_ad);
return ad;
}
ad = malloc(sizeof(*ad));
assert(ad != NULL);
ad->magic = KV5M_AUTHDATA;
ad->ad_type = atoi(typestr);
ad->length = strlen(contents);
ad->contents = (unsigned char *)strdup(contents);
assert(ad->contents != NULL);
return ad;
}
static krb5_authdata **
get_container_contents(krb5_authdata *ad, krb5_keyblock *skey,
krb5_keyblock *tktkey)
{
krb5_authdata **inner_ad;
if (ad->ad_type == KRB5_AUTHDATA_KDC_ISSUED)
check(krb5_verify_authdata_kdc_issued(ctx, skey, ad, NULL, &inner_ad));
else if (ad->ad_type == KRB5_AUTHDATA_CAMMAC)
check(k5_unwrap_cammac_svc(ctx, ad, tktkey, &inner_ad));
else
check(krb5_decode_authdata_container(ctx, ad->ad_type, ad, &inner_ad));
return inner_ad;
}
/* Decode and display authentication indicator authdata. */
static void
display_auth_indicator(krb5_authdata *ad)
{
krb5_data **strs = NULL, **p;
check(k5_authind_decode(ad, &strs));
assert(strs != NULL);
printf("[");
for (p = strs; *p != NULL; p++) {
printf("%.*s", (int)(*p)->length, (*p)->data);
if (*(p + 1) != NULL)
printf(", ");
}
printf("]");
k5_free_data_ptr_list(strs);
}
/* Display ad as either a hex dump or ASCII text. */
static void
display_binary_or_ascii(krb5_authdata *ad)
{
krb5_boolean binary = FALSE;
unsigned char *p;
for (p = ad->contents; p < ad->contents + ad->length; p++) {
if (!isascii(*p) || !isprint(*p))
binary = TRUE;
}
if (binary) {
for (p = ad->contents; p < ad->contents + ad->length; p++)
printf("%02X", *p);
} else {
printf("%.*s", (int)ad->length, ad->contents);
}
}
/* Display the contents of an authdata element, prefixed by prefix_byte. skey
* must be the ticket session key. */
static void
display_authdata(krb5_authdata *ad, krb5_keyblock *skey, krb5_keyblock *tktkey,
int prefix_byte, krb5_boolean pac_expected)
{
krb5_authdata **inner_ad;
if (ad->ad_type == KRB5_AUTHDATA_IF_RELEVANT ||
ad->ad_type == KRB5_AUTHDATA_MANDATORY_FOR_KDC ||
ad->ad_type == KRB5_AUTHDATA_KDC_ISSUED ||
ad->ad_type == KRB5_AUTHDATA_CAMMAC) {
if (ad->ad_type != KRB5_AUTHDATA_IF_RELEVANT)
pac_expected = FALSE;
/* Decode and display the contents. */
inner_ad = get_container_contents(ad, skey, tktkey);
display_authdata_list(inner_ad, skey, tktkey, get_prefix_byte(ad),
pac_expected);
krb5_free_authdata(ctx, inner_ad);
return;
}
assert(!pac_expected || ad->ad_type == KRB5_AUTHDATA_WIN2K_PAC);
printf("%c", prefix_byte);
printf("%d: ", (int)ad->ad_type);
if (ad->ad_type == KRB5_AUTHDATA_AUTH_INDICATOR)
display_auth_indicator(ad);
else
display_binary_or_ascii(ad);
printf("\n");
}
static void
display_authdata_list(krb5_authdata **list, krb5_keyblock *skey,
krb5_keyblock *tktkey, char prefix_byte,
krb5_boolean pac_expected)
{
if (list == NULL)
return;
/* Only expect a PAC in the first element, if at all. */
for (; *list != NULL; list++) {
display_authdata(*list, skey, tktkey, prefix_byte, pac_expected);
pac_expected = FALSE;
}
}
/* If a PAC is present in enc_part2, verify its service signature with key and
* set *has_pac to true. */
static void
check_pac(krb5_context context, krb5_enc_tkt_part *enc_part2,
const krb5_keyblock *key, krb5_boolean *has_pac)
{
krb5_authdata **authdata;
krb5_pac pac;
*has_pac = FALSE;
check(krb5_find_authdata(context, enc_part2->authorization_data, NULL,
KRB5_AUTHDATA_WIN2K_PAC, &authdata));
if (authdata == NULL)
return;
assert(authdata[1] == NULL);
check(krb5_pac_parse(context, authdata[0]->contents, authdata[0]->length,
&pac));
krb5_free_authdata(context, authdata);
check(krb5_pac_verify(context, pac, enc_part2->times.authtime,
enc_part2->client, key, NULL));
krb5_pac_free(context, pac);
*has_pac = TRUE;
}
int
main(int argc, char **argv)
{
const char *ccname = NULL, *clientname = NULL;
krb5_principal client, server;
krb5_ccache ccache;
krb5_keytab keytab;
krb5_creds in_creds, *creds;
krb5_ticket *ticket;
krb5_authdata **req_authdata = NULL, *ad;
krb5_keytab_entry ktent;
krb5_boolean with_pac;
size_t count;
int c;
check(krb5_init_context(&ctx));
while ((c = getopt(argc, argv, "+c:p:")) != -1) {
switch (c) {
case 'c':
ccname = optarg;
break;
case 'p':
clientname = optarg;
break;
default:
abort();
}
}
argv += optind;
/* Parse arguments. */
assert(*argv != NULL);
check(krb5_parse_name(ctx, *argv++, &server));
count = 0;
for (; argv[0] != NULL && argv[1] != NULL; argv += 2) {
ad = make_authdata(argv[0], argv[1]);
req_authdata = realloc(req_authdata,
(count + 2) * sizeof(*req_authdata));
assert(req_authdata != NULL);
req_authdata[count++] = ad;
req_authdata[count] = NULL;
}
assert(*argv == NULL);
if (ccname != NULL)
check(krb5_cc_resolve(ctx, ccname, &ccache));
else
check(krb5_cc_default(ctx, &ccache));
if (clientname != NULL)
check(krb5_parse_name(ctx, clientname, &client));
else
check(krb5_cc_get_principal(ctx, ccache, &client));
memset(&in_creds, 0, sizeof(in_creds));
in_creds.client = client;
in_creds.server = server;
in_creds.authdata = req_authdata;
check(krb5_get_credentials(ctx, KRB5_GC_NO_STORE, ccache, &in_creds,
&creds));
assert(in_creds.authdata == NULL || creds->authdata != NULL);
check(krb5_decode_ticket(&creds->ticket, &ticket));
check(krb5_kt_default(ctx, &keytab));
check(krb5_kt_get_entry(ctx, keytab, ticket->server, ticket->enc_part.kvno,
ticket->enc_part.enctype, &ktent));
check(krb5_decrypt_tkt_part(ctx, &ktent.key, ticket));
check_pac(ctx, ticket->enc_part2, &ktent.key, &with_pac);
display_authdata_list(ticket->enc_part2->authorization_data,
ticket->enc_part2->session, &ktent.key, ' ',
with_pac);
while (count > 0) {
free(req_authdata[--count]->contents);
free(req_authdata[count]);
}
free(req_authdata);
krb5_free_keytab_entry_contents(ctx, &ktent);
krb5_free_creds(ctx, creds);
krb5_free_ticket(ctx, ticket);
krb5_free_principal(ctx, client);
krb5_free_principal(ctx, server);
krb5_cc_close(ctx, ccache);
krb5_kt_close(ctx, keytab);
krb5_free_context(ctx);
return 0;
}