/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* tests/responder.c - Test harness for responder callbacks and the like. */
/*
* Copyright 2013 Red Hat, Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. 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 OWNER
* 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.
*/
/*
* A helper for testing PKINIT and responder callbacks.
*
* This test helper takes multiple options and one argument.
*
* responder [options] principal
* -X preauth_option -> preauth options, as for kinit
* -x challenge -> expected responder challenge, of the form
* "question=challenge"
* -r response -> provide a reponder answer, in the form
* "question=answer"
* -c -> print the pkinit challenge
* -p identity=pin -> provide a pkinit answer, in the form "identity=pin"
* -o index=value:pin -> provide an OTP answer, in the form "index=value:pin"
* principal -> client principal name
*
* If the responder callback isn't called, that's treated as an error.
*
* If an expected responder challenge is specified, when the responder
* callback is called, the challenge associated with the specified question is
* compared against the specified value. If the value provided to the
* callback doesn't parse as JSON, a literal string compare is performed,
* otherwise both values are parsed as JSON and then re-encoded before
* comparison. In either case, the comparison must succeed.
*
* Any missing data or mismatches are treated as errors.
*/
#include <k5-platform.h>
#include <k5-json.h>
#include <sys/types.h>
#include <unistd.h>
#include <krb5.h>
struct responder_data {
krb5_boolean called;
krb5_boolean print_pkinit_challenge;
const char *challenge;
const char *response;
const char *pkinit_answer;
const char *otp_answer;
};
static krb5_error_code
responder(krb5_context ctx, void *rawdata, krb5_responder_context rctx)
{
krb5_error_code err;
char *key, *value, *pin, *encoded1, *encoded2;
const char *challenge;
k5_json_value decoded1, decoded2;
k5_json_object ids;
k5_json_number val;
krb5_int32 token_flags;
struct responder_data *data = rawdata;
krb5_responder_pkinit_challenge *chl;
krb5_responder_otp_challenge *ochl;
unsigned int i, n;
data->called = TRUE;
/* Check that a particular challenge has the specified expected value. */
if (data->challenge != NULL) {
/* Separate the challenge name and its expected value. */
key = strdup(data->challenge);
if (key == NULL)
exit(ENOMEM);
value = key + strcspn(key, "=");
if (*value != '\0')
*value++ = '\0';
/* Read the challenge. */
challenge = krb5_responder_get_challenge(ctx, rctx, key);
err = k5_json_decode(value, &decoded1);
/* Check for "no challenge". */
if (challenge == NULL && *value == '\0') {
fprintf(stderr, "OK: (no challenge) == (no challenge)\n");
} else if (err != 0) {
/* It's not JSON, so assume we're just after a string compare. */
if (strcmp(challenge, value) == 0) {
fprintf(stderr, "OK: \"%s\" == \"%s\"\n", challenge, value);
} else {
fprintf(stderr, "ERROR: \"%s\" != \"%s\"\n", challenge, value);
exit(1);
}
} else {
/* Assume we're after a JSON compare - decode the actual value. */
err = k5_json_decode(challenge, &decoded2);
if (err != 0) {
fprintf(stderr, "error decoding \"%s\"\n", challenge);
exit(1);
}
/* Re-encode the expected challenge and the actual challenge... */
err = k5_json_encode(decoded1, &encoded1);
if (err != 0) {
fprintf(stderr, "error encoding json data\n");
exit(1);
}
err = k5_json_encode(decoded2, &encoded2);
if (err != 0) {
fprintf(stderr, "error encoding json data\n");
exit(1);
}
k5_json_release(decoded1);
k5_json_release(decoded2);
/* ... and see if they look the same. */
if (strcmp(encoded1, encoded2) == 0) {
fprintf(stderr, "OK: \"%s\" == \"%s\"\n", encoded1, encoded2);
} else {
fprintf(stderr, "ERROR: \"%s\" != \"%s\"\n", encoded1,
encoded2);
exit(1);
}
free(encoded1);
free(encoded2);
}
free(key);
}
/* Provide a particular response for a challenge. */
if (data->response != NULL) {
/* Separate the challenge and its data content... */
key = strdup(data->response);
if (key == NULL)
exit(ENOMEM);
value = key + strcspn(key, "=");
if (*value != '\0')
*value++ = '\0';
/* ... and pass it in. */
err = krb5_responder_set_answer(ctx, rctx, key, value);
if (err != 0) {
fprintf(stderr, "error setting response\n");
exit(1);
}
free(key);
}
if (data->print_pkinit_challenge) {
/* Read the PKINIT challenge, formatted as a structure. */
err = krb5_responder_pkinit_get_challenge(ctx, rctx, &chl);
if (err != 0) {
fprintf(stderr, "error getting pkinit challenge\n");
exit(1);
}
if (chl != NULL) {
for (n = 0; chl->identities[n] != NULL; n++)
continue;
for (i = 0; chl->identities[i] != NULL; i++) {
if (chl->identities[i]->token_flags != -1) {
printf("identity %u/%u: %s (flags=0x%lx)\n", i + 1, n,
chl->identities[i]->identity,
(long)chl->identities[i]->token_flags);
} else {
printf("identity %u/%u: %s\n", i + 1, n,
chl->identities[i]->identity);
}
}
}
krb5_responder_pkinit_challenge_free(ctx, rctx, chl);
}
/* Provide a particular response for the PKINIT challenge. */
if (data->pkinit_answer != NULL) {
/* Read the PKINIT challenge, formatted as a structure. */
err = krb5_responder_pkinit_get_challenge(ctx, rctx, &chl);
if (err != 0) {
fprintf(stderr, "error getting pkinit challenge\n");
exit(1);
}
/*
* In case order matters, if the identity starts with "FILE:", exercise
* the set_answer function, with the real answer second.
*/
if (chl != NULL &&
chl->identities != NULL &&
chl->identities[0] != NULL) {
if (strncmp(chl->identities[0]->identity, "FILE:", 5) == 0)
krb5_responder_pkinit_set_answer(ctx, rctx, "foo", "bar");
}
/* Provide the real answer. */
key = strdup(data->pkinit_answer);
if (key == NULL)
exit(ENOMEM);
value = strrchr(key, '=');
if (value != NULL)
*value++ = '\0';
else
value = "";
err = krb5_responder_pkinit_set_answer(ctx, rctx, key, value);
if (err != 0) {
fprintf(stderr, "error setting response\n");
exit(1);
}
free(key);
/*
* In case order matters, if the identity starts with "PKCS12:",
* exercise the set_answer function, with the real answer first.
*/
if (chl != NULL &&
chl->identities != NULL &&
chl->identities[0] != NULL) {
if (strncmp(chl->identities[0]->identity, "PKCS12:", 7) == 0)
krb5_responder_pkinit_set_answer(ctx, rctx, "foo", "bar");
}
krb5_responder_pkinit_challenge_free(ctx, rctx, chl);
}
/*
* Something we always check: read the PKINIT challenge, both as a
* structure and in JSON form, reconstruct the JSON form from the
* structure's contents, and check that they're the same.
*/
challenge = krb5_responder_get_challenge(ctx, rctx,
KRB5_RESPONDER_QUESTION_PKINIT);
if (challenge != NULL) {
krb5_responder_pkinit_get_challenge(ctx, rctx, &chl);
if (chl == NULL) {
fprintf(stderr, "pkinit raw challenge set, "
"but structure is NULL\n");
exit(1);
}
if (k5_json_object_create(&ids) != 0) {
fprintf(stderr, "error creating json objects\n");
exit(1);
}
for (i = 0; chl->identities[i] != NULL; i++) {
token_flags = chl->identities[i]->token_flags;
if (k5_json_number_create(token_flags, &val) != 0) {
fprintf(stderr, "error creating json number\n");
exit(1);
}
if (k5_json_object_set(ids, chl->identities[i]->identity,
val) != 0) {
fprintf(stderr, "error adding json number to object\n");
exit(1);
}
k5_json_release(val);
}
/* Encode the structure... */
err = k5_json_encode(ids, &encoded1);
if (err != 0) {
fprintf(stderr, "error encoding json data\n");
exit(1);
}
k5_json_release(ids);
/* ... and see if they look the same. */
if (strcmp(encoded1, challenge) != 0) {
fprintf(stderr, "\"%s\" != \"%s\"\n", encoded1, challenge);
exit(1);
}
krb5_responder_pkinit_challenge_free(ctx, rctx, chl);
free(encoded1);
}
/* Provide a particular response for an OTP challenge. */
if (data->otp_answer != NULL) {
if (krb5_responder_otp_get_challenge(ctx, rctx, &ochl) == 0) {
key = strchr(data->otp_answer, '=');
if (key != NULL) {
/* Make a copy of the answer that we can chop up. */
key = strdup(data->otp_answer);
if (key == NULL)
return ENOMEM;
/* Isolate the ti value. */
value = strchr(key, '=');
*value++ = '\0';
n = atoi(key);
/* Break the value and PIN apart. */
pin = strchr(value, ':');
if (pin != NULL)
*pin++ = '\0';
err = krb5_responder_otp_set_answer(ctx, rctx, n, value, pin);
if (err != 0) {
fprintf(stderr, "error setting response\n");
exit(1);
}
free(key);
}
krb5_responder_otp_challenge_free(ctx, rctx, ochl);
}
}
return 0;
}
int
main(int argc, char **argv)
{
krb5_context context;
krb5_ccache ccache;
krb5_get_init_creds_opt *opts;
krb5_principal principal;
krb5_creds creds;
krb5_error_code err;
const char *errmsg;
char *opt, *val;
struct responder_data response;
int c;
err = krb5_init_context(&context);
if (err != 0) {
fprintf(stderr, "error starting Kerberos: %s\n", error_message(err));
return err;
}
err = krb5_get_init_creds_opt_alloc(context, &opts);
if (err != 0) {
fprintf(stderr, "error initializing options: %s\n",
error_message(err));
return err;
}
err = krb5_cc_default(context, &ccache);
if (err != 0) {
fprintf(stderr, "error resolving default ccache: %s\n",
error_message(err));
return err;
}
err = krb5_get_init_creds_opt_set_out_ccache(context, opts, ccache);
if (err != 0) {
fprintf(stderr, "error setting output ccache: %s\n",
error_message(err));
return err;
}
memset(&response, 0, sizeof(response));
while ((c = getopt(argc, argv, "X:x:cr:p:")) != -1) {
switch (c) {
case 'X':
/* Like kinit, set a generic preauth option. */
opt = strdup(optarg);
val = opt + strcspn(opt, "=");
if (*val != '\0') {
*val++ = '\0';
}
err = krb5_get_init_creds_opt_set_pa(context, opts, opt, val);
if (err != 0) {
fprintf(stderr, "error setting option \"%s\": %s\n", opt,
error_message(err));
return err;
}
free(opt);
break;
case 'x':
/* Check that a particular question has a specific challenge. */
response.challenge = optarg;
break;
case 'c':
/* Note that we want a dump of the PKINIT challenge structure. */
response.print_pkinit_challenge = TRUE;
break;
case 'r':
/* Set a verbatim response for a verbatim challenge. */
response.response = optarg;
break;
case 'p':
/* Set a PKINIT answer for a specific PKINIT identity. */
response.pkinit_answer = optarg;
break;
case 'o':
/* Set an OTP answer for a specific OTP tokeninfo. */
response.otp_answer = optarg;
break;
}
}
if (argc > optind) {
err = krb5_parse_name(context, argv[optind], &principal);
if (err != 0) {
fprintf(stderr, "error parsing name \"%s\": %s", argv[optind],
error_message(err));
return err;
}
} else {
fprintf(stderr, "error: no principal name provided\n");
return -1;
}
err = krb5_get_init_creds_opt_set_responder(context, opts,
responder, &response);
if (err != 0) {
fprintf(stderr, "error setting responder: %s\n", error_message(err));
return err;
}
memset(&creds, 0, sizeof(creds));
err = krb5_get_init_creds_password(context, &creds, principal, NULL,
NULL, NULL, 0, NULL, opts);
if (err == 0)
krb5_free_cred_contents(context, &creds);
krb5_free_principal(context, principal);
krb5_get_init_creds_opt_free(context, opts);
krb5_cc_close(context, ccache);
if (!response.called) {
fprintf(stderr, "error: responder callback wasn't called\n");
err = 1;
} else if (err) {
errmsg = krb5_get_error_message(context, err);
fprintf(stderr, "error: krb5_get_init_creds_password failed: %s\n",
errmsg);
krb5_free_error_message(context, errmsg);
err = 2;
}
krb5_free_context(context);
return err;
}