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heimdal/lib/krb5/rd_req.c
Nicolas Williams b4cf4de807 Fix warnings (clang 3.6)
2016-02-26 01:04:31 -06:00

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/*
* Copyright (c) 1997 - 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 "krb5_locl.h"
static krb5_error_code
decrypt_tkt_enc_part (krb5_context context,
krb5_keyblock *key,
EncryptedData *enc_part,
EncTicketPart *decr_part)
{
krb5_error_code ret;
krb5_data plain;
size_t len;
krb5_crypto crypto;
ret = krb5_crypto_init(context, key, 0, &crypto);
if (ret)
return ret;
ret = krb5_decrypt_EncryptedData (context,
crypto,
KRB5_KU_TICKET,
enc_part,
&plain);
krb5_crypto_destroy(context, crypto);
if (ret)
return ret;
ret = decode_EncTicketPart(plain.data, plain.length, decr_part, &len);
if (ret)
krb5_set_error_message(context, ret,
N_("Failed to decode encrypted "
"ticket part", ""));
krb5_data_free (&plain);
return ret;
}
static krb5_error_code
decrypt_authenticator (krb5_context context,
EncryptionKey *key,
EncryptedData *enc_part,
Authenticator *authenticator,
krb5_key_usage usage)
{
krb5_error_code ret;
krb5_data plain;
size_t len;
krb5_crypto crypto;
ret = krb5_crypto_init(context, key, 0, &crypto);
if (ret)
return ret;
ret = krb5_decrypt_EncryptedData (context,
crypto,
usage /* KRB5_KU_AP_REQ_AUTH */,
enc_part,
&plain);
/* for backwards compatibility, also try the old usage */
if (ret && usage == KRB5_KU_TGS_REQ_AUTH)
ret = krb5_decrypt_EncryptedData (context,
crypto,
KRB5_KU_AP_REQ_AUTH,
enc_part,
&plain);
krb5_crypto_destroy(context, crypto);
if (ret)
return ret;
ret = decode_Authenticator(plain.data, plain.length,
authenticator, &len);
krb5_data_free (&plain);
return ret;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_decode_ap_req(krb5_context context,
const krb5_data *inbuf,
krb5_ap_req *ap_req)
{
krb5_error_code ret;
size_t len;
ret = decode_AP_REQ(inbuf->data, inbuf->length, ap_req, &len);
if (ret)
return ret;
if (ap_req->pvno != 5){
free_AP_REQ(ap_req);
krb5_clear_error_message (context);
return KRB5KRB_AP_ERR_BADVERSION;
}
if (ap_req->msg_type != krb_ap_req){
free_AP_REQ(ap_req);
krb5_clear_error_message (context);
return KRB5KRB_AP_ERR_MSG_TYPE;
}
if (ap_req->ticket.tkt_vno != 5){
free_AP_REQ(ap_req);
krb5_clear_error_message (context);
return KRB5KRB_AP_ERR_BADVERSION;
}
return 0;
}
static krb5_error_code
check_transited(krb5_context context, Ticket *ticket, EncTicketPart *enc)
{
char **realms;
unsigned int num_realms, n;
krb5_error_code ret;
/*
* Windows 2000 and 2003 uses this inside their TGT so it's normaly
* not seen by others, however, samba4 joined with a Windows AD as
* a Domain Controller gets exposed to this.
*/
if(enc->transited.tr_type == 0 && enc->transited.contents.length == 0)
return 0;
if(enc->transited.tr_type != DOMAIN_X500_COMPRESS)
return KRB5KDC_ERR_TRTYPE_NOSUPP;
if(enc->transited.contents.length == 0)
return 0;
ret = krb5_domain_x500_decode(context, enc->transited.contents,
&realms, &num_realms,
enc->crealm,
ticket->realm);
if(ret)
return ret;
ret = krb5_check_transited(context, enc->crealm,
ticket->realm,
realms, num_realms, NULL);
for (n = 0; n < num_realms; n++)
free(realms[n]);
free(realms);
return ret;
}
static krb5_error_code
find_etypelist(krb5_context context,
krb5_auth_context auth_context,
EtypeList *etypes)
{
krb5_error_code ret;
krb5_data data;
ret = _krb5_get_ad(context, auth_context->authenticator->authorization_data, NULL, KRB5_AUTHDATA_GSS_API_ETYPE_NEGOTIATION, &data);
if (ret)
return 0;
ret = decode_EtypeList(data.data, data.length, etypes, NULL);
krb5_data_free(&data);
if (ret)
krb5_clear_error_message(context);
return ret;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_decrypt_ticket(krb5_context context,
Ticket *ticket,
krb5_keyblock *key,
EncTicketPart *out,
krb5_flags flags)
{
EncTicketPart t;
krb5_error_code ret;
ret = decrypt_tkt_enc_part (context, key, &ticket->enc_part, &t);
if (ret)
return ret;
{
krb5_timestamp now;
time_t start = t.authtime;
krb5_timeofday (context, &now);
if(t.starttime)
start = *t.starttime;
if(start - now > context->max_skew
|| (t.flags.invalid
&& !(flags & KRB5_VERIFY_AP_REQ_IGNORE_INVALID))) {
free_EncTicketPart(&t);
krb5_clear_error_message (context);
return KRB5KRB_AP_ERR_TKT_NYV;
}
if(now - t.endtime > context->max_skew) {
free_EncTicketPart(&t);
krb5_clear_error_message (context);
return KRB5KRB_AP_ERR_TKT_EXPIRED;
}
if(!t.flags.transited_policy_checked) {
ret = check_transited(context, ticket, &t);
if(ret) {
free_EncTicketPart(&t);
return ret;
}
}
}
if(out)
*out = t;
else
free_EncTicketPart(&t);
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_verify_authenticator_checksum(krb5_context context,
krb5_auth_context ac,
void *data,
size_t len)
{
krb5_error_code ret;
krb5_keyblock *key;
krb5_authenticator authenticator;
krb5_crypto crypto;
ret = krb5_auth_con_getauthenticator (context,
ac,
&authenticator);
if(ret)
return ret;
if(authenticator->cksum == NULL) {
krb5_free_authenticator(context, &authenticator);
return -17;
}
ret = krb5_auth_con_getkey(context, ac, &key);
if(ret) {
krb5_free_authenticator(context, &authenticator);
return ret;
}
ret = krb5_crypto_init(context, key, 0, &crypto);
if(ret)
goto out;
ret = krb5_verify_checksum (context,
crypto,
KRB5_KU_AP_REQ_AUTH_CKSUM,
data,
len,
authenticator->cksum);
krb5_crypto_destroy(context, crypto);
out:
krb5_free_authenticator(context, &authenticator);
krb5_free_keyblock(context, key);
return ret;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_verify_ap_req(krb5_context context,
krb5_auth_context *auth_context,
krb5_ap_req *ap_req,
krb5_const_principal server,
krb5_keyblock *keyblock,
krb5_flags flags,
krb5_flags *ap_req_options,
krb5_ticket **ticket)
{
return krb5_verify_ap_req2 (context,
auth_context,
ap_req,
server,
keyblock,
flags,
ap_req_options,
ticket,
KRB5_KU_AP_REQ_AUTH);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_verify_ap_req2(krb5_context context,
krb5_auth_context *auth_context,
krb5_ap_req *ap_req,
krb5_const_principal server,
krb5_keyblock *keyblock,
krb5_flags flags,
krb5_flags *ap_req_options,
krb5_ticket **ticket,
krb5_key_usage usage)
{
krb5_ticket *t;
krb5_auth_context ac;
krb5_error_code ret;
EtypeList etypes;
memset(&etypes, 0, sizeof(etypes));
if (ticket)
*ticket = NULL;
if (auth_context && *auth_context) {
ac = *auth_context;
} else {
ret = krb5_auth_con_init (context, &ac);
if (ret)
return ret;
}
t = calloc(1, sizeof(*t));
if (t == NULL) {
ret = krb5_enomem(context);
goto out;
}
if (ap_req->ap_options.use_session_key && ac->keyblock){
ret = krb5_decrypt_ticket(context, &ap_req->ticket,
ac->keyblock,
&t->ticket,
flags);
krb5_free_keyblock(context, ac->keyblock);
ac->keyblock = NULL;
}else
ret = krb5_decrypt_ticket(context, &ap_req->ticket,
keyblock,
&t->ticket,
flags);
if(ret)
goto out;
ret = _krb5_principalname2krb5_principal(context,
&t->server,
ap_req->ticket.sname,
ap_req->ticket.realm);
if (ret) goto out;
ret = _krb5_principalname2krb5_principal(context,
&t->client,
t->ticket.cname,
t->ticket.crealm);
if (ret) goto out;
ret = decrypt_authenticator (context,
&t->ticket.key,
&ap_req->authenticator,
ac->authenticator,
usage);
if (ret)
goto out;
{
krb5_principal p1, p2;
krb5_boolean res;
_krb5_principalname2krb5_principal(context,
&p1,
ac->authenticator->cname,
ac->authenticator->crealm);
_krb5_principalname2krb5_principal(context,
&p2,
t->ticket.cname,
t->ticket.crealm);
res = krb5_principal_compare (context, p1, p2);
krb5_free_principal (context, p1);
krb5_free_principal (context, p2);
if (!res) {
ret = KRB5KRB_AP_ERR_BADMATCH;
krb5_clear_error_message (context);
goto out;
}
}
/* check addresses */
if (t->ticket.caddr
&& ac->remote_address
&& !krb5_address_search (context,
ac->remote_address,
t->ticket.caddr)) {
ret = KRB5KRB_AP_ERR_BADADDR;
krb5_clear_error_message (context);
goto out;
}
/* check timestamp in authenticator */
{
krb5_timestamp now;
krb5_timeofday (context, &now);
if (labs(ac->authenticator->ctime - now) > context->max_skew) {
ret = KRB5KRB_AP_ERR_SKEW;
krb5_clear_error_message (context);
goto out;
}
}
if (ac->authenticator->seq_number)
krb5_auth_con_setremoteseqnumber(context, ac,
*ac->authenticator->seq_number);
/* XXX - Xor sequence numbers */
if (ac->authenticator->subkey) {
ret = krb5_auth_con_setremotesubkey(context, ac,
ac->authenticator->subkey);
if (ret)
goto out;
}
ret = find_etypelist(context, ac, &etypes);
if (ret)
goto out;
ac->keytype = ETYPE_NULL;
if (etypes.val) {
size_t i;
for (i = 0; i < etypes.len; i++) {
if (krb5_enctype_valid(context, etypes.val[i]) == 0) {
ac->keytype = etypes.val[i];
break;
}
}
}
/* save key */
ret = krb5_copy_keyblock(context, &t->ticket.key, &ac->keyblock);
if (ret) goto out;
if (ap_req_options) {
*ap_req_options = 0;
if (ac->keytype != (krb5_enctype)ETYPE_NULL)
*ap_req_options |= AP_OPTS_USE_SUBKEY;
if (ap_req->ap_options.use_session_key)
*ap_req_options |= AP_OPTS_USE_SESSION_KEY;
if (ap_req->ap_options.mutual_required)
*ap_req_options |= AP_OPTS_MUTUAL_REQUIRED;
}
if(ticket)
*ticket = t;
else
krb5_free_ticket (context, t);
if (auth_context) {
if (*auth_context == NULL)
*auth_context = ac;
} else
krb5_auth_con_free (context, ac);
free_EtypeList(&etypes);
return 0;
out:
free_EtypeList(&etypes);
if (t)
krb5_free_ticket (context, t);
if (auth_context == NULL || *auth_context == NULL)
krb5_auth_con_free (context, ac);
return ret;
}
/*
*
*/
struct krb5_rd_req_in_ctx_data {
krb5_keytab keytab;
krb5_keyblock *keyblock;
krb5_boolean check_pac;
};
struct krb5_rd_req_out_ctx_data {
krb5_keyblock *keyblock;
krb5_flags ap_req_options;
krb5_ticket *ticket;
krb5_principal server;
};
/**
* Allocate a krb5_rd_req_in_ctx as an input parameter to
* krb5_rd_req_ctx(). The caller should free the context with
* krb5_rd_req_in_ctx_free() when done with the context.
*
* @param context Keberos 5 context.
* @param ctx in ctx to krb5_rd_req_ctx().
*
* @return Kerberos 5 error code, see krb5_get_error_message().
*
* @ingroup krb5_auth
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_in_ctx_alloc(krb5_context context, krb5_rd_req_in_ctx *ctx)
{
*ctx = calloc(1, sizeof(**ctx));
if (*ctx == NULL)
return krb5_enomem(context);
(*ctx)->check_pac = (context->flags & KRB5_CTX_F_CHECK_PAC) ? 1 : 0;
return 0;
}
/**
* Set the keytab that krb5_rd_req_ctx() will use.
*
* @param context Keberos 5 context.
* @param in in ctx to krb5_rd_req_ctx().
* @param keytab keytab that krb5_rd_req_ctx() will use, only copy the
* pointer, so the caller must free they keytab after
* krb5_rd_req_in_ctx_free() is called.
*
* @return Kerberos 5 error code, see krb5_get_error_message().
*
* @ingroup krb5_auth
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_in_set_keytab(krb5_context context,
krb5_rd_req_in_ctx in,
krb5_keytab keytab)
{
in->keytab = keytab;
return 0;
}
/**
* Set if krb5_rq_red() is going to check the Windows PAC or not
*
* @param context Keberos 5 context.
* @param in krb5_rd_req_in_ctx to check the option on.
* @param flag flag to select if to check the pac (TRUE) or not (FALSE).
*
* @return Kerberos 5 error code, see krb5_get_error_message().
*
* @ingroup krb5_auth
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_in_set_pac_check(krb5_context context,
krb5_rd_req_in_ctx in,
krb5_boolean flag)
{
in->check_pac = flag;
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_in_set_keyblock(krb5_context context,
krb5_rd_req_in_ctx in,
krb5_keyblock *keyblock)
{
in->keyblock = keyblock; /* XXX should make copy */
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_out_get_ap_req_options(krb5_context context,
krb5_rd_req_out_ctx out,
krb5_flags *ap_req_options)
{
*ap_req_options = out->ap_req_options;
return 0;
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_out_get_ticket(krb5_context context,
krb5_rd_req_out_ctx out,
krb5_ticket **ticket)
{
return krb5_copy_ticket(context, out->ticket, ticket);
}
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_out_get_keyblock(krb5_context context,
krb5_rd_req_out_ctx out,
krb5_keyblock **keyblock)
{
return krb5_copy_keyblock(context, out->keyblock, keyblock);
}
/**
* Get the principal that was used in the request from the
* client. Might not match whats in the ticket if krb5_rd_req_ctx()
* searched in the keytab for a matching key.
*
* @param context a Kerberos 5 context.
* @param out a krb5_rd_req_out_ctx from krb5_rd_req_ctx().
* @param principal return principal, free with krb5_free_principal().
*
* @ingroup krb5_auth
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_out_get_server(krb5_context context,
krb5_rd_req_out_ctx out,
krb5_principal *principal)
{
return krb5_copy_principal(context, out->server, principal);
}
KRB5_LIB_FUNCTION void KRB5_LIB_CALL
krb5_rd_req_in_ctx_free(krb5_context context, krb5_rd_req_in_ctx ctx)
{
free(ctx);
}
/**
* Free the krb5_rd_req_out_ctx.
*
* @param context Keberos 5 context.
* @param ctx krb5_rd_req_out_ctx context to free.
*
* @ingroup krb5_auth
*/
KRB5_LIB_FUNCTION void KRB5_LIB_CALL
krb5_rd_req_out_ctx_free(krb5_context context, krb5_rd_req_out_ctx ctx)
{
if (ctx->ticket)
krb5_free_ticket(context, ctx->ticket);
if (ctx->keyblock)
krb5_free_keyblock(context, ctx->keyblock);
if (ctx->server)
krb5_free_principal(context, ctx->server);
free(ctx);
}
/**
* Process an AP_REQ message.
*
* @param context Kerberos 5 context.
* @param auth_context authentication context of the peer.
* @param inbuf the AP_REQ message, obtained for example with krb5_read_message().
* @param server server principal.
* @param keytab server keytab.
* @param ap_req_options set to the AP_REQ options. See the AP_OPTS_* defines.
* @param ticket on success, set to the authenticated client credentials.
* Must be deallocated with krb5_free_ticket(). If not
* interested, pass a NULL value.
*
* @return 0 to indicate success. Otherwise a Kerberos error code is
* returned, see krb5_get_error_message().
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req(krb5_context context,
krb5_auth_context *auth_context,
const krb5_data *inbuf,
krb5_const_principal server,
krb5_keytab keytab,
krb5_flags *ap_req_options,
krb5_ticket **ticket)
{
krb5_error_code ret;
krb5_rd_req_in_ctx in;
krb5_rd_req_out_ctx out;
ret = krb5_rd_req_in_ctx_alloc(context, &in);
if (ret)
return ret;
ret = krb5_rd_req_in_set_keytab(context, in, keytab);
if (ret) {
krb5_rd_req_in_ctx_free(context, in);
return ret;
}
ret = krb5_rd_req_ctx(context, auth_context, inbuf, server, in, &out);
krb5_rd_req_in_ctx_free(context, in);
if (ret)
return ret;
if (ap_req_options)
*ap_req_options = out->ap_req_options;
if (ticket) {
ret = krb5_copy_ticket(context, out->ticket, ticket);
if (ret)
goto out;
}
out:
krb5_rd_req_out_ctx_free(context, out);
return ret;
}
/*
*
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_with_keyblock(krb5_context context,
krb5_auth_context *auth_context,
const krb5_data *inbuf,
krb5_const_principal server,
krb5_keyblock *keyblock,
krb5_flags *ap_req_options,
krb5_ticket **ticket)
{
krb5_error_code ret;
krb5_rd_req_in_ctx in;
krb5_rd_req_out_ctx out;
ret = krb5_rd_req_in_ctx_alloc(context, &in);
if (ret)
return ret;
ret = krb5_rd_req_in_set_keyblock(context, in, keyblock);
if (ret) {
krb5_rd_req_in_ctx_free(context, in);
return ret;
}
ret = krb5_rd_req_ctx(context, auth_context, inbuf, server, in, &out);
krb5_rd_req_in_ctx_free(context, in);
if (ret)
return ret;
if (ap_req_options)
*ap_req_options = out->ap_req_options;
if (ticket) {
ret = krb5_copy_ticket(context, out->ticket, ticket);
if (ret)
goto out;
}
out:
krb5_rd_req_out_ctx_free(context, out);
return ret;
}
/*
*
*/
static krb5_error_code
get_key_from_keytab(krb5_context context,
krb5_ap_req *ap_req,
krb5_const_principal server,
krb5_keytab keytab,
krb5_keyblock **out_key)
{
krb5_keytab_entry entry;
krb5_error_code ret;
int kvno;
krb5_keytab real_keytab;
if(keytab == NULL)
krb5_kt_default(context, &real_keytab);
else
real_keytab = keytab;
if (ap_req->ticket.enc_part.kvno)
kvno = *ap_req->ticket.enc_part.kvno;
else
kvno = 0;
ret = krb5_kt_get_entry (context,
real_keytab,
server,
kvno,
ap_req->ticket.enc_part.etype,
&entry);
if(ret)
goto out;
ret = krb5_copy_keyblock(context, &entry.keyblock, out_key);
krb5_kt_free_entry (context, &entry);
out:
if(keytab == NULL)
krb5_kt_close(context, real_keytab);
return ret;
}
/**
* The core server function that verify application authentication
* requests from clients.
*
* @param context Keberos 5 context.
* @param auth_context the authentication context, can be NULL, then
* default values for the authentication context will used.
* @param inbuf the (AP-REQ) authentication buffer
*
* @param server the server to authenticate to. If NULL the function
* will try to find any available credential in the keytab
* that will verify the reply. The function will prefer the
* server specified in the AP-REQ, but if
* there is no mach, it will try all keytab entries for a
* match. This has serious performance issues for large keytabs.
*
* @param inctx control the behavior of the function, if NULL, the
* default behavior is used.
* @param outctx the return outctx, free with krb5_rd_req_out_ctx_free().
* @return Kerberos 5 error code, see krb5_get_error_message().
*
* @ingroup krb5_auth
*/
KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
krb5_rd_req_ctx(krb5_context context,
krb5_auth_context *auth_context,
const krb5_data *inbuf,
krb5_const_principal server,
krb5_rd_req_in_ctx inctx,
krb5_rd_req_out_ctx *outctx)
{
krb5_error_code ret;
krb5_ap_req ap_req;
krb5_rd_req_out_ctx o = NULL;
krb5_keytab id = NULL, keytab = NULL;
krb5_principal service = NULL;
*outctx = NULL;
o = calloc(1, sizeof(*o));
if (o == NULL)
return krb5_enomem(context);
if (*auth_context == NULL) {
ret = krb5_auth_con_init(context, auth_context);
if (ret)
goto out;
}
ret = krb5_decode_ap_req(context, inbuf, &ap_req);
if(ret)
goto out;
/* Save the principal that was in the request */
ret = _krb5_principalname2krb5_principal(context,
&o->server,
ap_req.ticket.sname,
ap_req.ticket.realm);
if (ret)
goto out;
if (ap_req.ap_options.use_session_key &&
(*auth_context)->keyblock == NULL) {
ret = KRB5KRB_AP_ERR_NOKEY;
krb5_set_error_message(context, ret,
N_("krb5_rd_req: user to user auth "
"without session key given", ""));
goto out;
}
if (inctx && inctx->keytab)
id = inctx->keytab;
if((*auth_context)->keyblock){
ret = krb5_copy_keyblock(context,
(*auth_context)->keyblock,
&o->keyblock);
if (ret)
goto out;
} else if(inctx && inctx->keyblock){
ret = krb5_copy_keyblock(context,
inctx->keyblock,
&o->keyblock);
if (ret)
goto out;
} else {
if(id == NULL) {
krb5_kt_default(context, &keytab);
id = keytab;
}
if (id == NULL)
goto out;
if (server == NULL) {
ret = _krb5_principalname2krb5_principal(context,
&service,
ap_req.ticket.sname,
ap_req.ticket.realm);
if (ret)
goto out;
server = service;
}
ret = get_key_from_keytab(context,
&ap_req,
server,
id,
&o->keyblock);
if (ret) {
/* If caller specified a server, fail. */
if (service == NULL && (context->flags & KRB5_CTX_F_RD_REQ_IGNORE) == 0)
goto out;
/* Otherwise, fall back to iterating over the keytab. This
* have serious performace issues for larger keytab.
*/
o->keyblock = NULL;
}
}
if (o->keyblock) {
/*
* We got an exact keymatch, use that.
*/
ret = krb5_verify_ap_req2(context,
auth_context,
&ap_req,
server,
o->keyblock,
0,
&o->ap_req_options,
&o->ticket,
KRB5_KU_AP_REQ_AUTH);
if (ret)
goto out;
} else {
/*
* Interate over keytab to find a key that can decrypt the request.
*/
krb5_keytab_entry entry;
krb5_kt_cursor cursor;
int done = 0, kvno = 0;
memset(&cursor, 0, sizeof(cursor));
if (ap_req.ticket.enc_part.kvno)
kvno = *ap_req.ticket.enc_part.kvno;
ret = krb5_kt_start_seq_get(context, id, &cursor);
if (ret)
goto out;
done = 0;
while (!done) {
krb5_principal p;
ret = krb5_kt_next_entry(context, id, &entry, &cursor);
if (ret) {
_krb5_kt_principal_not_found(context, ret, id, o->server,
ap_req.ticket.enc_part.etype,
kvno);
break;
}
if (entry.keyblock.keytype != ap_req.ticket.enc_part.etype) {
krb5_kt_free_entry (context, &entry);
continue;
}
ret = krb5_verify_ap_req2(context,
auth_context,
&ap_req,
server,
&entry.keyblock,
0,
&o->ap_req_options,
&o->ticket,
KRB5_KU_AP_REQ_AUTH);
if (ret) {
krb5_kt_free_entry (context, &entry);
continue;
}
/*
* Found a match, save the keyblock for PAC processing,
* and update the service principal in the ticket to match
* whatever is in the keytab.
*/
ret = krb5_copy_keyblock(context,
&entry.keyblock,
&o->keyblock);
if (ret) {
krb5_kt_free_entry (context, &entry);
break;
}
ret = krb5_copy_principal(context, entry.principal, &p);
if (ret) {
krb5_kt_free_entry (context, &entry);
break;
}
krb5_free_principal(context, o->ticket->server);
o->ticket->server = p;
krb5_kt_free_entry (context, &entry);
done = 1;
}
krb5_kt_end_seq_get (context, id, &cursor);
if (ret)
goto out;
}
/* If there is a PAC, verify its server signature */
if (inctx == NULL || inctx->check_pac) {
krb5_pac pac;
krb5_data data;
ret = krb5_ticket_get_authorization_data_type(context,
o->ticket,
KRB5_AUTHDATA_WIN2K_PAC,
&data);
if (ret == 0) {
ret = krb5_pac_parse(context, data.data, data.length, &pac);
krb5_data_free(&data);
if (ret)
goto out;
ret = krb5_pac_verify(context,
pac,
o->ticket->ticket.authtime,
o->ticket->client,
o->keyblock,
NULL);
krb5_pac_free(context, pac);
if (ret)
goto out;
} else
ret = 0;
}
out:
if (ret || outctx == NULL) {
krb5_rd_req_out_ctx_free(context, o);
} else
*outctx = o;
free_AP_REQ(&ap_req);
if (service)
krb5_free_principal(context, service);
if (keytab)
krb5_kt_close(context, keytab);
return ret;
}
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