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freebsd-nq/crypto/heimdal/kdc/digest.c
Stanislav Sedov ae77177087 - Update FreeBSD Heimdal distribution to version 1.5.1. This also brings 
several new kerberos related libraries and applications to FreeBSD:
  o kgetcred(1) allows one to manually get a ticket for a particular service.
  o kf(1) securily forwards ticket to another host through an authenticated
    and encrypted stream.
  o kcc(1) is an umbrella program around klist(1), kswitch(1), kgetcred(1)
    and other user kerberos operations. klist and kswitch are just symlinks
    to kcc(1) now.
  o kswitch(1) allows you to easily switch between kerberos credentials if
    you're running KCM.
  o hxtool(1) is a certificate management tool to use with PKINIT.
  o string2key(1) maps a password into key.
  o kdigest(8) is a userland tool to access the KDC's digest interface.
  o kimpersonate(8) creates a "fake" ticket for a service.

  We also now install manpages for some lirbaries that were not installed
  before, libheimntlm and libhx509.

- The new HEIMDAL version no longer supports Kerberos 4.  All users are
  recommended to switch to Kerberos 5.

- Weak ciphers are now disabled by default.  To enable DES support (used
  by telnet(8)), use "allow_weak_crypto" option in krb5.conf.

- libtelnet, pam_ksu and pam_krb5 are now compiled with error on warnings
  disabled due to the function they use (krb5_get_err_text(3)) being
  deprecated.  I plan to work on this next.

- Heimdal's KDC now require sqlite to operate.  We use the bundled version
  and install it as libheimsqlite.  If some other FreeBSD components will
  require it in the future we can rename it to libbsdsqlite and use for these
  components as well.

- This is not a latest Heimdal version, the new one was released while I was
  working on the update.  I will update it to 1.5.2 soon, as it fixes some
  important bugs and security issues.
2012-03-22 08:48:42 +00:00

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/*
* Copyright (c) 2006 - 2007 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* 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.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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.
*/
#include "kdc_locl.h"
#include <hex.h>
#ifdef DIGEST
#define MS_CHAP_V2 0x20
#define CHAP_MD5 0x10
#define DIGEST_MD5 0x08
#define NTLM_V2 0x04
#define NTLM_V1_SESSION 0x02
#define NTLM_V1 0x01
const struct units _kdc_digestunits[] = {
{"ms-chap-v2", 1U << 5},
{"chap-md5", 1U << 4},
{"digest-md5", 1U << 3},
{"ntlm-v2", 1U << 2},
{"ntlm-v1-session", 1U << 1},
{"ntlm-v1", 1U << 0},
{NULL, 0}
};
static krb5_error_code
get_digest_key(krb5_context context,
krb5_kdc_configuration *config,
hdb_entry_ex *server,
krb5_crypto *crypto)
{
krb5_error_code ret;
krb5_enctype enctype;
Key *key;
ret = _kdc_get_preferred_key(context,
config,
server,
"digest-service",
&enctype,
&key);
if (ret)
return ret;
return krb5_crypto_init(context, &key->key, 0, crypto);
}
/*
*
*/
static char *
get_ntlm_targetname(krb5_context context,
hdb_entry_ex *client)
{
char *targetname, *p;
targetname = strdup(krb5_principal_get_realm(context,
client->entry.principal));
if (targetname == NULL)
return NULL;
p = strchr(targetname, '.');
if (p)
*p = '\0';
strupr(targetname);
return targetname;
}
static krb5_error_code
fill_targetinfo(krb5_context context,
char *targetname,
hdb_entry_ex *client,
krb5_data *data)
{
struct ntlm_targetinfo ti;
krb5_error_code ret;
struct ntlm_buf d;
krb5_principal p;
const char *str;
memset(&ti, 0, sizeof(ti));
ti.domainname = targetname;
p = client->entry.principal;
str = krb5_principal_get_comp_string(context, p, 0);
if (str != NULL &&
(strcmp("host", str) == 0 ||
strcmp("ftp", str) == 0 ||
strcmp("imap", str) == 0 ||
strcmp("pop", str) == 0 ||
strcmp("smtp", str)))
{
str = krb5_principal_get_comp_string(context, p, 1);
ti.dnsservername = rk_UNCONST(str);
}
ret = heim_ntlm_encode_targetinfo(&ti, 1, &d);
if (ret)
return ret;
data->data = d.data;
data->length = d.length;
return 0;
}
static const unsigned char ms_chap_v2_magic1[39] = {
0x4D, 0x61, 0x67, 0x69, 0x63, 0x20, 0x73, 0x65, 0x72, 0x76,
0x65, 0x72, 0x20, 0x74, 0x6F, 0x20, 0x63, 0x6C, 0x69, 0x65,
0x6E, 0x74, 0x20, 0x73, 0x69, 0x67, 0x6E, 0x69, 0x6E, 0x67,
0x20, 0x63, 0x6F, 0x6E, 0x73, 0x74, 0x61, 0x6E, 0x74
};
static const unsigned char ms_chap_v2_magic2[41] = {
0x50, 0x61, 0x64, 0x20, 0x74, 0x6F, 0x20, 0x6D, 0x61, 0x6B,
0x65, 0x20, 0x69, 0x74, 0x20, 0x64, 0x6F, 0x20, 0x6D, 0x6F,
0x72, 0x65, 0x20, 0x74, 0x68, 0x61, 0x6E, 0x20, 0x6F, 0x6E,
0x65, 0x20, 0x69, 0x74, 0x65, 0x72, 0x61, 0x74, 0x69, 0x6F,
0x6E
};
static const unsigned char ms_rfc3079_magic1[27] = {
0x54, 0x68, 0x69, 0x73, 0x20, 0x69, 0x73, 0x20, 0x74,
0x68, 0x65, 0x20, 0x4d, 0x50, 0x50, 0x45, 0x20, 0x4d,
0x61, 0x73, 0x74, 0x65, 0x72, 0x20, 0x4b, 0x65, 0x79
};
/*
*
*/
static krb5_error_code
get_password_entry(krb5_context context,
krb5_kdc_configuration *config,
const char *username,
char **password)
{
krb5_principal clientprincipal;
krb5_error_code ret;
hdb_entry_ex *user;
HDB *db;
/* get username */
ret = krb5_parse_name(context, username, &clientprincipal);
if (ret)
return ret;
ret = _kdc_db_fetch(context, config, clientprincipal,
HDB_F_GET_CLIENT, NULL, &db, &user);
krb5_free_principal(context, clientprincipal);
if (ret)
return ret;
ret = hdb_entry_get_password(context, db, &user->entry, password);
if (ret || password == NULL) {
if (ret == 0) {
ret = EINVAL;
krb5_set_error_message(context, ret, "password missing");
}
memset(user, 0, sizeof(*user));
}
_kdc_free_ent (context, user);
return ret;
}
/*
*
*/
krb5_error_code
_kdc_do_digest(krb5_context context,
krb5_kdc_configuration *config,
const struct DigestREQ *req, krb5_data *reply,
const char *from, struct sockaddr *addr)
{
krb5_error_code ret = 0;
krb5_ticket *ticket = NULL;
krb5_auth_context ac = NULL;
krb5_keytab id = NULL;
krb5_crypto crypto = NULL;
DigestReqInner ireq;
DigestRepInner r;
DigestREP rep;
krb5_flags ap_req_options;
krb5_data buf;
size_t size;
krb5_storage *sp = NULL;
Checksum res;
hdb_entry_ex *server = NULL, *user = NULL;
hdb_entry_ex *client = NULL;
char *client_name = NULL, *password = NULL;
krb5_data serverNonce;
if(!config->enable_digest) {
kdc_log(context, config, 0,
"Rejected digest request (disabled) from %s", from);
return KRB5KDC_ERR_POLICY;
}
krb5_data_zero(&buf);
krb5_data_zero(reply);
krb5_data_zero(&serverNonce);
memset(&ireq, 0, sizeof(ireq));
memset(&r, 0, sizeof(r));
memset(&rep, 0, sizeof(rep));
memset(&res, 0, sizeof(res));
kdc_log(context, config, 0, "Digest request from %s", from);
ret = krb5_kt_resolve(context, "HDB:", &id);
if (ret) {
kdc_log(context, config, 0, "Can't open database for digest");
goto out;
}
ret = krb5_rd_req(context,
&ac,
&req->apReq,
NULL,
id,
&ap_req_options,
&ticket);
if (ret)
goto out;
/* check the server principal in the ticket matches digest/R@R */
{
krb5_principal principal = NULL;
const char *p, *rr;
ret = krb5_ticket_get_server(context, ticket, &principal);
if (ret)
goto out;
ret = EINVAL;
krb5_set_error_message(context, ret, "Wrong digest server principal used");
p = krb5_principal_get_comp_string(context, principal, 0);
if (p == NULL) {
krb5_free_principal(context, principal);
goto out;
}
if (strcmp(p, KRB5_DIGEST_NAME) != 0) {
krb5_free_principal(context, principal);
goto out;
}
p = krb5_principal_get_comp_string(context, principal, 1);
if (p == NULL) {
krb5_free_principal(context, principal);
goto out;
}
rr = krb5_principal_get_realm(context, principal);
if (rr == NULL) {
krb5_free_principal(context, principal);
goto out;
}
if (strcmp(p, rr) != 0) {
krb5_free_principal(context, principal);
goto out;
}
krb5_clear_error_message(context);
ret = _kdc_db_fetch(context, config, principal,
HDB_F_GET_SERVER, NULL, NULL, &server);
if (ret)
goto out;
krb5_free_principal(context, principal);
}
/* check the client is allowed to do digest auth */
{
krb5_principal principal = NULL;
ret = krb5_ticket_get_client(context, ticket, &principal);
if (ret)
goto out;
ret = krb5_unparse_name(context, principal, &client_name);
if (ret) {
krb5_free_principal(context, principal);
goto out;
}
ret = _kdc_db_fetch(context, config, principal,
HDB_F_GET_CLIENT, NULL, NULL, &client);
krb5_free_principal(context, principal);
if (ret)
goto out;
if (client->entry.flags.allow_digest == 0) {
kdc_log(context, config, 0,
"Client %s tried to use digest "
"but is not allowed to",
client_name);
ret = KRB5KDC_ERR_POLICY;
krb5_set_error_message(context, ret,
"Client is not permitted to use digest");
goto out;
}
}
/* unpack request */
{
krb5_keyblock *key;
ret = krb5_auth_con_getremotesubkey(context, ac, &key);
if (ret)
goto out;
if (key == NULL) {
ret = EINVAL;
krb5_set_error_message(context, ret, "digest: remote subkey not found");
goto out;
}
ret = krb5_crypto_init(context, key, 0, &crypto);
krb5_free_keyblock (context, key);
if (ret)
goto out;
}
ret = krb5_decrypt_EncryptedData(context, crypto, KRB5_KU_DIGEST_ENCRYPT,
&req->innerReq, &buf);
krb5_crypto_destroy(context, crypto);
crypto = NULL;
if (ret)
goto out;
ret = decode_DigestReqInner(buf.data, buf.length, &ireq, NULL);
krb5_data_free(&buf);
if (ret) {
krb5_set_error_message(context, ret, "Failed to decode digest inner request");
goto out;
}
kdc_log(context, config, 0, "Valid digest request from %s (%s)",
client_name, from);
/*
* Process the inner request
*/
switch (ireq.element) {
case choice_DigestReqInner_init: {
unsigned char server_nonce[16], identifier;
RAND_pseudo_bytes(&identifier, sizeof(identifier));
RAND_pseudo_bytes(server_nonce, sizeof(server_nonce));
server_nonce[0] = kdc_time & 0xff;
server_nonce[1] = (kdc_time >> 8) & 0xff;
server_nonce[2] = (kdc_time >> 16) & 0xff;
server_nonce[3] = (kdc_time >> 24) & 0xff;
r.element = choice_DigestRepInner_initReply;
hex_encode(server_nonce, sizeof(server_nonce), &r.u.initReply.nonce);
if (r.u.initReply.nonce == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "Failed to decode server nonce");
goto out;
}
sp = krb5_storage_emem();
if (sp == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
ret = krb5_store_stringz(sp, ireq.u.init.type);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
if (ireq.u.init.channel) {
char *s;
asprintf(&s, "%s-%s:%s", r.u.initReply.nonce,
ireq.u.init.channel->cb_type,
ireq.u.init.channel->cb_binding);
if (s == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret,
"Failed to allocate channel binding");
goto out;
}
free(r.u.initReply.nonce);
r.u.initReply.nonce = s;
}
ret = krb5_store_stringz(sp, r.u.initReply.nonce);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
if (strcasecmp(ireq.u.init.type, "CHAP") == 0) {
r.u.initReply.identifier =
malloc(sizeof(*r.u.initReply.identifier));
if (r.u.initReply.identifier == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
asprintf(r.u.initReply.identifier, "%02X", identifier & 0xff);
if (*r.u.initReply.identifier == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
} else
r.u.initReply.identifier = NULL;
if (ireq.u.init.hostname) {
ret = krb5_store_stringz(sp, *ireq.u.init.hostname);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
}
ret = krb5_storage_to_data(sp, &buf);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
ret = get_digest_key(context, config, server, &crypto);
if (ret)
goto out;
ret = krb5_create_checksum(context,
crypto,
KRB5_KU_DIGEST_OPAQUE,
0,
buf.data,
buf.length,
&res);
krb5_crypto_destroy(context, crypto);
crypto = NULL;
krb5_data_free(&buf);
if (ret)
goto out;
ASN1_MALLOC_ENCODE(Checksum, buf.data, buf.length, &res, &size, ret);
free_Checksum(&res);
if (ret) {
krb5_set_error_message(context, ret, "Failed to encode "
"checksum in digest request");
goto out;
}
if (size != buf.length)
krb5_abortx(context, "ASN1 internal error");
hex_encode(buf.data, buf.length, &r.u.initReply.opaque);
free(buf.data);
krb5_data_zero(&buf);
if (r.u.initReply.opaque == NULL) {
krb5_clear_error_message(context);
ret = ENOMEM;
goto out;
}
kdc_log(context, config, 0, "Digest %s init request successful from %s",
ireq.u.init.type, from);
break;
}
case choice_DigestReqInner_digestRequest: {
sp = krb5_storage_emem();
if (sp == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
ret = krb5_store_stringz(sp, ireq.u.digestRequest.type);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
krb5_store_stringz(sp, ireq.u.digestRequest.serverNonce);
if (ireq.u.digestRequest.hostname) {
ret = krb5_store_stringz(sp, *ireq.u.digestRequest.hostname);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
}
buf.length = strlen(ireq.u.digestRequest.opaque);
buf.data = malloc(buf.length);
if (buf.data == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
ret = hex_decode(ireq.u.digestRequest.opaque, buf.data, buf.length);
if (ret <= 0) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "Failed to decode opaque");
goto out;
}
buf.length = ret;
ret = decode_Checksum(buf.data, buf.length, &res, NULL);
free(buf.data);
krb5_data_zero(&buf);
if (ret) {
krb5_set_error_message(context, ret,
"Failed to decode digest Checksum");
goto out;
}
ret = krb5_storage_to_data(sp, &buf);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
serverNonce.length = strlen(ireq.u.digestRequest.serverNonce);
serverNonce.data = malloc(serverNonce.length);
if (serverNonce.data == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
/*
* CHAP does the checksum of the raw nonce, but do it for all
* types, since we need to check the timestamp.
*/
{
ssize_t ssize;
ssize = hex_decode(ireq.u.digestRequest.serverNonce,
serverNonce.data, serverNonce.length);
if (ssize <= 0) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "Failed to decode serverNonce");
goto out;
}
serverNonce.length = ssize;
}
ret = get_digest_key(context, config, server, &crypto);
if (ret)
goto out;
ret = krb5_verify_checksum(context, crypto,
KRB5_KU_DIGEST_OPAQUE,
buf.data, buf.length, &res);
free_Checksum(&res);
krb5_data_free(&buf);
krb5_crypto_destroy(context, crypto);
crypto = NULL;
if (ret)
goto out;
/* verify time */
{
unsigned char *p = serverNonce.data;
uint32_t t;
if (serverNonce.length < 4) {
ret = EINVAL;
krb5_set_error_message(context, ret, "server nonce too short");
goto out;
}
t = p[0] | (p[1] << 8) | (p[2] << 16) | (p[3] << 24);
if (abs((kdc_time & 0xffffffff) - t) > context->max_skew) {
ret = EINVAL;
krb5_set_error_message(context, ret, "time screw in server nonce ");
goto out;
}
}
if (strcasecmp(ireq.u.digestRequest.type, "CHAP") == 0) {
EVP_MD_CTX *ctx;
unsigned char md[MD5_DIGEST_LENGTH];
char *mdx;
char idx;
if ((config->digests_allowed & CHAP_MD5) == 0) {
kdc_log(context, config, 0, "Digest CHAP MD5 not allowed");
goto out;
}
if (ireq.u.digestRequest.identifier == NULL) {
ret = EINVAL;
krb5_set_error_message(context, ret, "Identifier missing "
"from CHAP request");
goto out;
}
if (hex_decode(*ireq.u.digestRequest.identifier, &idx, 1) != 1) {
ret = EINVAL;
krb5_set_error_message(context, ret, "failed to decode identifier");
goto out;
}
ret = get_password_entry(context, config,
ireq.u.digestRequest.username,
&password);
if (ret)
goto out;
ctx = EVP_MD_CTX_create();
EVP_DigestInit_ex(ctx, EVP_md5(), NULL);
EVP_DigestUpdate(ctx, &idx, 1);
EVP_DigestUpdate(ctx, password, strlen(password));
EVP_DigestUpdate(ctx, serverNonce.data, serverNonce.length);
EVP_DigestFinal_ex(ctx, md, NULL);
EVP_MD_CTX_destroy(ctx);
hex_encode(md, sizeof(md), &mdx);
if (mdx == NULL) {
krb5_clear_error_message(context);
ret = ENOMEM;
goto out;
}
r.element = choice_DigestRepInner_response;
ret = strcasecmp(mdx, ireq.u.digestRequest.responseData);
free(mdx);
if (ret == 0) {
r.u.response.success = TRUE;
} else {
kdc_log(context, config, 0,
"CHAP reply mismatch for %s",
ireq.u.digestRequest.username);
r.u.response.success = FALSE;
}
} else if (strcasecmp(ireq.u.digestRequest.type, "SASL-DIGEST-MD5") == 0) {
EVP_MD_CTX *ctx;
unsigned char md[MD5_DIGEST_LENGTH];
char *mdx;
char *A1, *A2;
if ((config->digests_allowed & DIGEST_MD5) == 0) {
kdc_log(context, config, 0, "Digest SASL MD5 not allowed");
goto out;
}
if (ireq.u.digestRequest.nonceCount == NULL)
goto out;
if (ireq.u.digestRequest.clientNonce == NULL)
goto out;
if (ireq.u.digestRequest.qop == NULL)
goto out;
if (ireq.u.digestRequest.realm == NULL)
goto out;
ret = get_password_entry(context, config,
ireq.u.digestRequest.username,
&password);
if (ret)
goto failed;
ctx = EVP_MD_CTX_create();
EVP_DigestInit_ex(ctx, EVP_md5(), NULL);
EVP_DigestUpdate(ctx, ireq.u.digestRequest.username,
strlen(ireq.u.digestRequest.username));
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, *ireq.u.digestRequest.realm,
strlen(*ireq.u.digestRequest.realm));
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, password, strlen(password));
EVP_DigestFinal_ex(ctx, md, NULL);
EVP_DigestInit_ex(ctx, EVP_md5(), NULL);
EVP_DigestUpdate(ctx, md, sizeof(md));
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, ireq.u.digestRequest.serverNonce,
strlen(ireq.u.digestRequest.serverNonce));
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, *ireq.u.digestRequest.nonceCount,
strlen(*ireq.u.digestRequest.nonceCount));
if (ireq.u.digestRequest.authid) {
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, *ireq.u.digestRequest.authid,
strlen(*ireq.u.digestRequest.authid));
}
EVP_DigestFinal_ex(ctx, md, NULL);
hex_encode(md, sizeof(md), &A1);
if (A1 == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
EVP_MD_CTX_destroy(ctx);
goto failed;
}
EVP_DigestInit_ex(ctx, EVP_md5(), NULL);
EVP_DigestUpdate(ctx,
"AUTHENTICATE:", sizeof("AUTHENTICATE:") - 1);
EVP_DigestUpdate(ctx, *ireq.u.digestRequest.uri,
strlen(*ireq.u.digestRequest.uri));
/* conf|int */
if (strcmp(ireq.u.digestRequest.digest, "clear") != 0) {
static char conf_zeros[] = ":00000000000000000000000000000000";
EVP_DigestUpdate(ctx, conf_zeros, sizeof(conf_zeros) - 1);
}
EVP_DigestFinal_ex(ctx, md, NULL);
hex_encode(md, sizeof(md), &A2);
if (A2 == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
free(A1);
goto failed;
}
EVP_DigestInit_ex(ctx, EVP_md5(), NULL);
EVP_DigestUpdate(ctx, A1, strlen(A2));
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, ireq.u.digestRequest.serverNonce,
strlen(ireq.u.digestRequest.serverNonce));
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, *ireq.u.digestRequest.nonceCount,
strlen(*ireq.u.digestRequest.nonceCount));
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, *ireq.u.digestRequest.clientNonce,
strlen(*ireq.u.digestRequest.clientNonce));
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, *ireq.u.digestRequest.qop,
strlen(*ireq.u.digestRequest.qop));
EVP_DigestUpdate(ctx, ":", 1);
EVP_DigestUpdate(ctx, A2, strlen(A2));
EVP_DigestFinal_ex(ctx, md, NULL);
EVP_MD_CTX_destroy(ctx);
free(A1);
free(A2);
hex_encode(md, sizeof(md), &mdx);
if (mdx == NULL) {
krb5_clear_error_message(context);
ret = ENOMEM;
goto out;
}
r.element = choice_DigestRepInner_response;
ret = strcasecmp(mdx, ireq.u.digestRequest.responseData);
free(mdx);
if (ret == 0) {
r.u.response.success = TRUE;
} else {
kdc_log(context, config, 0,
"DIGEST-MD5 reply mismatch for %s",
ireq.u.digestRequest.username);
r.u.response.success = FALSE;
}
} else if (strcasecmp(ireq.u.digestRequest.type, "MS-CHAP-V2") == 0) {
unsigned char md[SHA_DIGEST_LENGTH], challange[SHA_DIGEST_LENGTH];
krb5_principal clientprincipal = NULL;
char *mdx;
const char *username;
struct ntlm_buf answer;
Key *key = NULL;
EVP_MD_CTX *ctp;
if ((config->digests_allowed & MS_CHAP_V2) == 0) {
kdc_log(context, config, 0, "MS-CHAP-V2 not allowed");
goto failed;
}
if (ireq.u.digestRequest.clientNonce == NULL) {
ret = EINVAL;
krb5_set_error_message(context, ret,
"MS-CHAP-V2 clientNonce missing");
goto failed;
}
if (serverNonce.length != 16) {
ret = EINVAL;
krb5_set_error_message(context, ret,
"MS-CHAP-V2 serverNonce wrong length");
goto failed;
}
/* strip of the domain component */
username = strchr(ireq.u.digestRequest.username, '\\');
if (username == NULL)
username = ireq.u.digestRequest.username;
else
username++;
ctp = EVP_MD_CTX_create();
/* ChallangeHash */
EVP_DigestInit_ex(ctp, EVP_sha1(), NULL);
{
ssize_t ssize;
krb5_data clientNonce;
clientNonce.length = strlen(*ireq.u.digestRequest.clientNonce);
clientNonce.data = malloc(clientNonce.length);
if (clientNonce.data == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret,
"malloc: out of memory");
EVP_MD_CTX_destroy(ctp);
goto out;
}
ssize = hex_decode(*ireq.u.digestRequest.clientNonce,
clientNonce.data, clientNonce.length);
if (ssize != 16) {
ret = ENOMEM;
krb5_set_error_message(context, ret,
"Failed to decode clientNonce");
EVP_MD_CTX_destroy(ctp);
goto out;
}
EVP_DigestUpdate(ctp, clientNonce.data, ssize);
free(clientNonce.data);
}
EVP_DigestUpdate(ctp, serverNonce.data, serverNonce.length);
EVP_DigestUpdate(ctp, username, strlen(username));
EVP_DigestFinal_ex(ctp, challange, NULL);
EVP_MD_CTX_destroy(ctp);
/* NtPasswordHash */
ret = krb5_parse_name(context, username, &clientprincipal);
if (ret)
goto failed;
ret = _kdc_db_fetch(context, config, clientprincipal,
HDB_F_GET_CLIENT, NULL, NULL, &user);
krb5_free_principal(context, clientprincipal);
if (ret) {
krb5_set_error_message(context, ret,
"MS-CHAP-V2 user %s not in database",
username);
goto failed;
}
ret = hdb_enctype2key(context, &user->entry,
ETYPE_ARCFOUR_HMAC_MD5, &key);
if (ret) {
krb5_set_error_message(context, ret,
"MS-CHAP-V2 missing arcfour key %s",
username);
goto failed;
}
/* ChallengeResponse */
ret = heim_ntlm_calculate_ntlm1(key->key.keyvalue.data,
key->key.keyvalue.length,
challange, &answer);
if (ret) {
krb5_set_error_message(context, ret, "NTLM missing arcfour key");
goto failed;
}
hex_encode(answer.data, answer.length, &mdx);
if (mdx == NULL) {
free(answer.data);
krb5_clear_error_message(context);
ret = ENOMEM;
goto out;
}
r.element = choice_DigestRepInner_response;
ret = strcasecmp(mdx, ireq.u.digestRequest.responseData);
if (ret == 0) {
r.u.response.success = TRUE;
} else {
kdc_log(context, config, 0,
"MS-CHAP-V2 hash mismatch for %s",
ireq.u.digestRequest.username);
r.u.response.success = FALSE;
}
free(mdx);
if (r.u.response.success) {
unsigned char hashhash[MD4_DIGEST_LENGTH];
EVP_MD_CTX *ctxp;
ctxp = EVP_MD_CTX_create();
/* hashhash */
{
EVP_DigestInit_ex(ctxp, EVP_md4(), NULL);
EVP_DigestUpdate(ctxp,
key->key.keyvalue.data,
key->key.keyvalue.length);
EVP_DigestFinal_ex(ctxp, hashhash, NULL);
}
/* GenerateAuthenticatorResponse */
EVP_DigestInit_ex(ctxp, EVP_sha1(), NULL);
EVP_DigestUpdate(ctxp, hashhash, sizeof(hashhash));
EVP_DigestUpdate(ctxp, answer.data, answer.length);
EVP_DigestUpdate(ctxp, ms_chap_v2_magic1,
sizeof(ms_chap_v2_magic1));
EVP_DigestFinal_ex(ctxp, md, NULL);
EVP_DigestInit_ex(ctxp, EVP_sha1(), NULL);
EVP_DigestUpdate(ctxp, md, sizeof(md));
EVP_DigestUpdate(ctxp, challange, 8);
EVP_DigestUpdate(ctxp, ms_chap_v2_magic2,
sizeof(ms_chap_v2_magic2));
EVP_DigestFinal_ex(ctxp, md, NULL);
r.u.response.rsp = calloc(1, sizeof(*r.u.response.rsp));
if (r.u.response.rsp == NULL) {
free(answer.data);
krb5_clear_error_message(context);
EVP_MD_CTX_destroy(ctxp);
ret = ENOMEM;
goto out;
}
hex_encode(md, sizeof(md), r.u.response.rsp);
if (r.u.response.rsp == NULL) {
free(answer.data);
krb5_clear_error_message(context);
EVP_MD_CTX_destroy(ctxp);
ret = ENOMEM;
goto out;
}
/* get_master, rfc 3079 3.4 */
EVP_DigestInit_ex(ctxp, EVP_sha1(), NULL);
EVP_DigestUpdate(ctxp, hashhash, 16);
EVP_DigestUpdate(ctxp, answer.data, answer.length);
EVP_DigestUpdate(ctxp, ms_rfc3079_magic1,
sizeof(ms_rfc3079_magic1));
EVP_DigestFinal_ex(ctxp, md, NULL);
free(answer.data);
EVP_MD_CTX_destroy(ctxp);
r.u.response.session_key =
calloc(1, sizeof(*r.u.response.session_key));
if (r.u.response.session_key == NULL) {
krb5_clear_error_message(context);
ret = ENOMEM;
goto out;
}
ret = krb5_data_copy(r.u.response.session_key, md, 16);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
}
} else {
r.element = choice_DigestRepInner_error;
asprintf(&r.u.error.reason, "Unsupported digest type %s",
ireq.u.digestRequest.type);
if (r.u.error.reason == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
r.u.error.code = EINVAL;
}
kdc_log(context, config, 0, "Digest %s request successful %s",
ireq.u.digestRequest.type, ireq.u.digestRequest.username);
break;
}
case choice_DigestReqInner_ntlmInit:
if ((config->digests_allowed & (NTLM_V1|NTLM_V1_SESSION|NTLM_V2)) == 0) {
kdc_log(context, config, 0, "NTLM not allowed");
goto failed;
}
r.element = choice_DigestRepInner_ntlmInitReply;
r.u.ntlmInitReply.flags = NTLM_NEG_UNICODE;
if ((ireq.u.ntlmInit.flags & NTLM_NEG_UNICODE) == 0) {
kdc_log(context, config, 0, "NTLM client have no unicode");
goto failed;
}
if (ireq.u.ntlmInit.flags & NTLM_NEG_NTLM)
r.u.ntlmInitReply.flags |= NTLM_NEG_NTLM;
else {
kdc_log(context, config, 0, "NTLM client doesn't support NTLM");
goto failed;
}
r.u.ntlmInitReply.flags |=
NTLM_NEG_TARGET |
NTLM_TARGET_DOMAIN |
NTLM_ENC_128;
#define ALL \
NTLM_NEG_SIGN| \
NTLM_NEG_SEAL| \
NTLM_NEG_ALWAYS_SIGN| \
NTLM_NEG_NTLM2_SESSION| \
NTLM_NEG_KEYEX
r.u.ntlmInitReply.flags |= (ireq.u.ntlmInit.flags & (ALL));
#undef ALL
r.u.ntlmInitReply.targetname =
get_ntlm_targetname(context, client);
if (r.u.ntlmInitReply.targetname == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
r.u.ntlmInitReply.challange.data = malloc(8);
if (r.u.ntlmInitReply.challange.data == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
r.u.ntlmInitReply.challange.length = 8;
if (RAND_bytes(r.u.ntlmInitReply.challange.data,
r.u.ntlmInitReply.challange.length) != 1)
{
ret = ENOMEM;
krb5_set_error_message(context, ret, "out of random error");
goto out;
}
/* XXX fix targetinfo */
ALLOC(r.u.ntlmInitReply.targetinfo);
if (r.u.ntlmInitReply.targetinfo == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
ret = fill_targetinfo(context,
r.u.ntlmInitReply.targetname,
client,
r.u.ntlmInitReply.targetinfo);
if (ret) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
/*
* Save data encryted in opaque for the second part of the
* ntlm authentication
*/
sp = krb5_storage_emem();
if (sp == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
ret = krb5_storage_write(sp, r.u.ntlmInitReply.challange.data, 8);
if (ret != 8) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "storage write challange");
goto out;
}
ret = krb5_store_uint32(sp, r.u.ntlmInitReply.flags);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
ret = krb5_storage_to_data(sp, &buf);
if (ret) {
krb5_clear_error_message(context);
goto out;
}
ret = get_digest_key(context, config, server, &crypto);
if (ret)
goto out;
ret = krb5_encrypt(context, crypto, KRB5_KU_DIGEST_OPAQUE,
buf.data, buf.length, &r.u.ntlmInitReply.opaque);
krb5_data_free(&buf);
krb5_crypto_destroy(context, crypto);
crypto = NULL;
if (ret)
goto out;
kdc_log(context, config, 0, "NTLM init from %s", from);
break;
case choice_DigestReqInner_ntlmRequest: {
krb5_principal clientprincipal;
unsigned char sessionkey[16];
unsigned char challange[8];
uint32_t flags;
Key *key = NULL;
int version;
r.element = choice_DigestRepInner_ntlmResponse;
r.u.ntlmResponse.success = 0;
r.u.ntlmResponse.flags = 0;
r.u.ntlmResponse.sessionkey = NULL;
r.u.ntlmResponse.tickets = NULL;
/* get username */
ret = krb5_parse_name(context,
ireq.u.ntlmRequest.username,
&clientprincipal);
if (ret)
goto failed;
ret = _kdc_db_fetch(context, config, clientprincipal,
HDB_F_GET_CLIENT, NULL, NULL, &user);
krb5_free_principal(context, clientprincipal);
if (ret) {
krb5_set_error_message(context, ret, "NTLM user %s not in database",
ireq.u.ntlmRequest.username);
goto failed;
}
ret = get_digest_key(context, config, server, &crypto);
if (ret)
goto failed;
ret = krb5_decrypt(context, crypto, KRB5_KU_DIGEST_OPAQUE,
ireq.u.ntlmRequest.opaque.data,
ireq.u.ntlmRequest.opaque.length, &buf);
krb5_crypto_destroy(context, crypto);
crypto = NULL;
if (ret) {
kdc_log(context, config, 0,
"Failed to decrypt nonce from %s", from);
goto failed;
}
sp = krb5_storage_from_data(&buf);
if (sp == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
ret = krb5_storage_read(sp, challange, sizeof(challange));
if (ret != sizeof(challange)) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "NTLM storage read challange");
goto out;
}
ret = krb5_ret_uint32(sp, &flags);
if (ret) {
krb5_set_error_message(context, ret, "NTLM storage read flags");
goto out;
}
krb5_storage_free(sp);
sp = NULL;
krb5_data_free(&buf);
if ((flags & NTLM_NEG_NTLM) == 0) {
ret = EINVAL;
krb5_set_error_message(context, ret, "NTLM not negotiated");
goto out;
}
ret = hdb_enctype2key(context, &user->entry,
ETYPE_ARCFOUR_HMAC_MD5, &key);
if (ret) {
krb5_set_error_message(context, ret, "NTLM missing arcfour key");
goto out;
}
/* check if this is NTLMv2 */
if (ireq.u.ntlmRequest.ntlm.length != 24) {
struct ntlm_buf infotarget, answer;
char *targetname;
if ((config->digests_allowed & NTLM_V2) == 0) {
kdc_log(context, config, 0, "NTLM v2 not allowed");
goto out;
}
version = 2;
targetname = get_ntlm_targetname(context, client);
if (targetname == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
answer.length = ireq.u.ntlmRequest.ntlm.length;
answer.data = ireq.u.ntlmRequest.ntlm.data;
ret = heim_ntlm_verify_ntlm2(key->key.keyvalue.data,
key->key.keyvalue.length,
ireq.u.ntlmRequest.username,
targetname,
0,
challange,
&answer,
&infotarget,
sessionkey);
free(targetname);
if (ret) {
krb5_set_error_message(context, ret, "NTLM v2 verify failed");
goto failed;
}
/* XXX verify infotarget matches client (checksum ?) */
free(infotarget.data);
/* */
} else {
struct ntlm_buf answer;
version = 1;
if (flags & NTLM_NEG_NTLM2_SESSION) {
unsigned char sessionhash[MD5_DIGEST_LENGTH];
EVP_MD_CTX *ctx;
if ((config->digests_allowed & NTLM_V1_SESSION) == 0) {
kdc_log(context, config, 0, "NTLM v1-session not allowed");
ret = EINVAL;
goto failed;
}
if (ireq.u.ntlmRequest.lm.length != 24) {
ret = EINVAL;
krb5_set_error_message(context, ret, "LM hash have wrong length "
"for NTLM session key");
goto failed;
}
ctx = EVP_MD_CTX_create();
EVP_DigestInit_ex(ctx, EVP_md5(), NULL);
EVP_DigestUpdate(ctx, challange, sizeof(challange));
EVP_DigestUpdate(ctx, ireq.u.ntlmRequest.lm.data, 8);
EVP_DigestFinal_ex(ctx, sessionhash, NULL);
memcpy(challange, sessionhash, sizeof(challange));
EVP_MD_CTX_destroy(ctx);
} else {
if ((config->digests_allowed & NTLM_V1) == 0) {
kdc_log(context, config, 0, "NTLM v1 not allowed");
goto failed;
}
}
ret = heim_ntlm_calculate_ntlm1(key->key.keyvalue.data,
key->key.keyvalue.length,
challange, &answer);
if (ret) {
krb5_set_error_message(context, ret, "NTLM missing arcfour key");
goto failed;
}
if (ireq.u.ntlmRequest.ntlm.length != answer.length ||
memcmp(ireq.u.ntlmRequest.ntlm.data, answer.data, answer.length) != 0)
{
free(answer.data);
ret = EINVAL;
krb5_set_error_message(context, ret, "NTLM hash mismatch");
goto failed;
}
free(answer.data);
{
EVP_MD_CTX *ctx;
ctx = EVP_MD_CTX_create();
EVP_DigestInit_ex(ctx, EVP_md4(), NULL);
EVP_DigestUpdate(ctx,
key->key.keyvalue.data,
key->key.keyvalue.length);
EVP_DigestFinal_ex(ctx, sessionkey, NULL);
EVP_MD_CTX_destroy(ctx);
}
}
if (ireq.u.ntlmRequest.sessionkey) {
unsigned char masterkey[MD4_DIGEST_LENGTH];
EVP_CIPHER_CTX rc4;
size_t len;
if ((flags & NTLM_NEG_KEYEX) == 0) {
ret = EINVAL;
krb5_set_error_message(context, ret,
"NTLM client failed to neg key "
"exchange but still sent key");
goto failed;
}
len = ireq.u.ntlmRequest.sessionkey->length;
if (len != sizeof(masterkey)){
ret = EINVAL;
krb5_set_error_message(context, ret,
"NTLM master key wrong length: %lu",
(unsigned long)len);
goto failed;
}
EVP_CIPHER_CTX_init(&rc4);
EVP_CipherInit_ex(&rc4, EVP_rc4(), NULL, sessionkey, NULL, 1);
EVP_Cipher(&rc4,
masterkey, ireq.u.ntlmRequest.sessionkey->data,
sizeof(masterkey));
EVP_CIPHER_CTX_cleanup(&rc4);
r.u.ntlmResponse.sessionkey =
malloc(sizeof(*r.u.ntlmResponse.sessionkey));
if (r.u.ntlmResponse.sessionkey == NULL) {
ret = EINVAL;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
ret = krb5_data_copy(r.u.ntlmResponse.sessionkey,
masterkey, sizeof(masterkey));
if (ret) {
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
}
r.u.ntlmResponse.success = 1;
kdc_log(context, config, 0, "NTLM version %d successful for %s",
version, ireq.u.ntlmRequest.username);
break;
}
case choice_DigestReqInner_supportedMechs:
kdc_log(context, config, 0, "digest supportedMechs from %s", from);
r.element = choice_DigestRepInner_supportedMechs;
memset(&r.u.supportedMechs, 0, sizeof(r.u.supportedMechs));
if (config->digests_allowed & NTLM_V1)
r.u.supportedMechs.ntlm_v1 = 1;
if (config->digests_allowed & NTLM_V1_SESSION)
r.u.supportedMechs.ntlm_v1_session = 1;
if (config->digests_allowed & NTLM_V2)
r.u.supportedMechs.ntlm_v2 = 1;
if (config->digests_allowed & DIGEST_MD5)
r.u.supportedMechs.digest_md5 = 1;
if (config->digests_allowed & CHAP_MD5)
r.u.supportedMechs.chap_md5 = 1;
if (config->digests_allowed & MS_CHAP_V2)
r.u.supportedMechs.ms_chap_v2 = 1;
break;
default: {
const char *s;
ret = EINVAL;
krb5_set_error_message(context, ret, "unknown operation to digest");
failed:
s = krb5_get_error_message(context, ret);
if (s == NULL) {
krb5_clear_error_message(context);
goto out;
}
kdc_log(context, config, 0, "Digest failed with: %s", s);
r.element = choice_DigestRepInner_error;
r.u.error.reason = strdup("unknown error");
krb5_free_error_message(context, s);
if (r.u.error.reason == NULL) {
ret = ENOMEM;
krb5_set_error_message(context, ret, "malloc: out of memory");
goto out;
}
r.u.error.code = EINVAL;
break;
}
}
ASN1_MALLOC_ENCODE(DigestRepInner, buf.data, buf.length, &r, &size, ret);
if (ret) {
krb5_set_error_message(context, ret, "Failed to encode inner digest reply");
goto out;
}
if (size != buf.length)
krb5_abortx(context, "ASN1 internal error");
krb5_auth_con_addflags(context, ac, KRB5_AUTH_CONTEXT_USE_SUBKEY, NULL);
ret = krb5_mk_rep (context, ac, &rep.apRep);
if (ret)
goto out;
{
krb5_keyblock *key;
ret = krb5_auth_con_getlocalsubkey(context, ac, &key);
if (ret)
goto out;
ret = krb5_crypto_init(context, key, 0, &crypto);
krb5_free_keyblock (context, key);
if (ret)
goto out;
}
ret = krb5_encrypt_EncryptedData(context, crypto, KRB5_KU_DIGEST_ENCRYPT,
buf.data, buf.length, 0,
&rep.innerRep);
ASN1_MALLOC_ENCODE(DigestREP, reply->data, reply->length, &rep, &size, ret);
if (ret) {
krb5_set_error_message(context, ret, "Failed to encode digest reply");
goto out;
}
if (size != reply->length)
krb5_abortx(context, "ASN1 internal error");
out:
if (ac)
krb5_auth_con_free(context, ac);
if (ret)
krb5_warn(context, ret, "Digest request from %s failed", from);
if (ticket)
krb5_free_ticket(context, ticket);
if (id)
krb5_kt_close(context, id);
if (crypto)
krb5_crypto_destroy(context, crypto);
if (sp)
krb5_storage_free(sp);
if (user)
_kdc_free_ent (context, user);
if (server)
_kdc_free_ent (context, server);
if (client)
_kdc_free_ent (context, client);
if (password) {
memset(password, 0, strlen(password));
free (password);
}
if (client_name)
free (client_name);
krb5_data_free(&buf);
krb5_data_free(&serverNonce);
free_Checksum(&res);
free_DigestREP(&rep);
free_DigestRepInner(&r);
free_DigestReqInner(&ireq);
return ret;
}
#endif /* DIGEST */
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