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|
/*
Unix SMB/CIFS implementation.
Kerberos backend for GENSEC
Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004
Copyright (C) Andrew Tridgell 2001
Copyright (C) Luke Howard 2002-2003
Copyright (C) Stefan Metzmacher 2004-2005
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "system/kerberos.h"
#include "auth/kerberos/kerberos.h"
#include "auth/auth.h"
#include "lib/socket/socket.h"
#include "lib/tsocket/tsocket.h"
#include "librpc/rpc/dcerpc.h"
#include "auth/credentials/credentials.h"
#include "auth/credentials/credentials_krb5.h"
#include "auth/kerberos/kerberos_credentials.h"
#include "auth/gensec/gensec.h"
#include "auth/gensec/gensec_proto.h"
#include "param/param.h"
#include "auth/auth_sam_reply.h"
#include "lib/util/util_net.h"
_PUBLIC_ NTSTATUS gensec_krb5_init(void);
enum GENSEC_KRB5_STATE {
GENSEC_KRB5_SERVER_START,
GENSEC_KRB5_CLIENT_START,
GENSEC_KRB5_CLIENT_MUTUAL_AUTH,
GENSEC_KRB5_DONE
};
struct gensec_krb5_state {
DATA_BLOB session_key;
DATA_BLOB pac;
enum GENSEC_KRB5_STATE state_position;
struct smb_krb5_context *smb_krb5_context;
krb5_auth_context auth_context;
krb5_data enc_ticket;
krb5_keyblock *keyblock;
krb5_ticket *ticket;
bool gssapi;
krb5_flags ap_req_options;
};
static int gensec_krb5_destroy(struct gensec_krb5_state *gensec_krb5_state)
{
if (!gensec_krb5_state->smb_krb5_context) {
/* We can't clean anything else up unless we started up this far */
return 0;
}
if (gensec_krb5_state->enc_ticket.length) {
kerberos_free_data_contents(gensec_krb5_state->smb_krb5_context->krb5_context,
&gensec_krb5_state->enc_ticket);
}
if (gensec_krb5_state->ticket) {
krb5_free_ticket(gensec_krb5_state->smb_krb5_context->krb5_context,
gensec_krb5_state->ticket);
}
/* ccache freed in a child destructor */
krb5_free_keyblock(gensec_krb5_state->smb_krb5_context->krb5_context,
gensec_krb5_state->keyblock);
if (gensec_krb5_state->auth_context) {
krb5_auth_con_free(gensec_krb5_state->smb_krb5_context->krb5_context,
gensec_krb5_state->auth_context);
}
return 0;
}
static NTSTATUS gensec_krb5_start(struct gensec_security *gensec_security, bool gssapi)
{
krb5_error_code ret;
struct gensec_krb5_state *gensec_krb5_state;
struct cli_credentials *creds;
const struct tsocket_address *tlocal_addr, *tremote_addr;
krb5_address my_krb5_addr, peer_krb5_addr;
creds = gensec_get_credentials(gensec_security);
if (!creds) {
return NT_STATUS_INVALID_PARAMETER;
}
gensec_krb5_state = talloc(gensec_security, struct gensec_krb5_state);
if (!gensec_krb5_state) {
return NT_STATUS_NO_MEMORY;
}
gensec_security->private_data = gensec_krb5_state;
gensec_krb5_state->smb_krb5_context = NULL;
gensec_krb5_state->auth_context = NULL;
gensec_krb5_state->ticket = NULL;
ZERO_STRUCT(gensec_krb5_state->enc_ticket);
gensec_krb5_state->keyblock = NULL;
gensec_krb5_state->session_key = data_blob(NULL, 0);
gensec_krb5_state->pac = data_blob(NULL, 0);
gensec_krb5_state->gssapi = gssapi;
talloc_set_destructor(gensec_krb5_state, gensec_krb5_destroy);
if (cli_credentials_get_krb5_context(creds,
gensec_security->settings->lp_ctx, &gensec_krb5_state->smb_krb5_context)) {
talloc_free(gensec_krb5_state);
return NT_STATUS_INTERNAL_ERROR;
}
ret = krb5_auth_con_init(gensec_krb5_state->smb_krb5_context->krb5_context, &gensec_krb5_state->auth_context);
if (ret) {
DEBUG(1,("gensec_krb5_start: krb5_auth_con_init failed (%s)\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context,
ret, gensec_krb5_state)));
talloc_free(gensec_krb5_state);
return NT_STATUS_INTERNAL_ERROR;
}
ret = krb5_auth_con_setflags(gensec_krb5_state->smb_krb5_context->krb5_context,
gensec_krb5_state->auth_context,
KRB5_AUTH_CONTEXT_DO_SEQUENCE);
if (ret) {
DEBUG(1,("gensec_krb5_start: krb5_auth_con_setflags failed (%s)\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context,
ret, gensec_krb5_state)));
talloc_free(gensec_krb5_state);
return NT_STATUS_INTERNAL_ERROR;
}
tlocal_addr = gensec_get_local_address(gensec_security);
if (tlocal_addr) {
ssize_t socklen;
struct sockaddr_storage ss;
socklen = tsocket_address_bsd_sockaddr(tlocal_addr,
(struct sockaddr *) &ss,
sizeof(struct sockaddr_storage));
if (socklen < 0) {
talloc_free(gensec_krb5_state);
return NT_STATUS_INTERNAL_ERROR;
}
ret = krb5_sockaddr2address(gensec_krb5_state->smb_krb5_context->krb5_context,
(const struct sockaddr *) &ss, &my_krb5_addr);
if (ret) {
DEBUG(1,("gensec_krb5_start: krb5_sockaddr2address (local) failed (%s)\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context,
ret, gensec_krb5_state)));
talloc_free(gensec_krb5_state);
return NT_STATUS_INTERNAL_ERROR;
}
}
tremote_addr = gensec_get_remote_address(gensec_security);
if (tremote_addr) {
ssize_t socklen;
struct sockaddr_storage ss;
socklen = tsocket_address_bsd_sockaddr(tremote_addr,
(struct sockaddr *) &ss,
sizeof(struct sockaddr_storage));
if (socklen < 0) {
talloc_free(gensec_krb5_state);
return NT_STATUS_INTERNAL_ERROR;
}
ret = krb5_sockaddr2address(gensec_krb5_state->smb_krb5_context->krb5_context,
(const struct sockaddr *) &ss, &peer_krb5_addr);
if (ret) {
DEBUG(1,("gensec_krb5_start: krb5_sockaddr2address (local) failed (%s)\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context,
ret, gensec_krb5_state)));
talloc_free(gensec_krb5_state);
return NT_STATUS_INTERNAL_ERROR;
}
}
ret = krb5_auth_con_setaddrs(gensec_krb5_state->smb_krb5_context->krb5_context,
gensec_krb5_state->auth_context,
tlocal_addr ? &my_krb5_addr : NULL,
tremote_addr ? &peer_krb5_addr : NULL);
if (ret) {
DEBUG(1,("gensec_krb5_start: krb5_auth_con_setaddrs failed (%s)\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context,
ret, gensec_krb5_state)));
talloc_free(gensec_krb5_state);
return NT_STATUS_INTERNAL_ERROR;
}
return NT_STATUS_OK;
}
static NTSTATUS gensec_krb5_common_server_start(struct gensec_security *gensec_security, bool gssapi)
{
NTSTATUS nt_status;
struct gensec_krb5_state *gensec_krb5_state;
nt_status = gensec_krb5_start(gensec_security, gssapi);
if (!NT_STATUS_IS_OK(nt_status)) {
return nt_status;
}
gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data;
gensec_krb5_state->state_position = GENSEC_KRB5_SERVER_START;
return NT_STATUS_OK;
}
static NTSTATUS gensec_krb5_server_start(struct gensec_security *gensec_security)
{
return gensec_krb5_common_server_start(gensec_security, false);
}
static NTSTATUS gensec_fake_gssapi_krb5_server_start(struct gensec_security *gensec_security)
{
return gensec_krb5_common_server_start(gensec_security, true);
}
static NTSTATUS gensec_krb5_common_client_start(struct gensec_security *gensec_security, bool gssapi)
{
struct gensec_krb5_state *gensec_krb5_state;
krb5_error_code ret;
NTSTATUS nt_status;
struct ccache_container *ccache_container;
const char *hostname;
const char *error_string;
const char *principal;
krb5_data in_data;
struct tevent_context *previous_ev;
hostname = gensec_get_target_hostname(gensec_security);
if (!hostname) {
DEBUG(1, ("Could not determine hostname for target computer, cannot use kerberos\n"));
return NT_STATUS_INVALID_PARAMETER;
}
if (is_ipaddress(hostname)) {
DEBUG(2, ("Cannot do krb5 to an IP address"));
return NT_STATUS_INVALID_PARAMETER;
}
if (strcmp(hostname, "localhost") == 0) {
DEBUG(2, ("krb5 to 'localhost' does not make sense"));
return NT_STATUS_INVALID_PARAMETER;
}
nt_status = gensec_krb5_start(gensec_security, gssapi);
if (!NT_STATUS_IS_OK(nt_status)) {
return nt_status;
}
gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data;
gensec_krb5_state->state_position = GENSEC_KRB5_CLIENT_START;
gensec_krb5_state->ap_req_options = AP_OPTS_USE_SUBKEY;
if (gensec_krb5_state->gssapi) {
/* The Fake GSSAPI modal emulates Samba3, which does not do mutual authentication */
if (gensec_setting_bool(gensec_security->settings, "gensec_fake_gssapi_krb5", "mutual", false)) {
gensec_krb5_state->ap_req_options |= AP_OPTS_MUTUAL_REQUIRED;
}
} else {
/* The wrapping for KPASSWD (a user of the raw KRB5 API) should be mutually authenticated */
if (gensec_setting_bool(gensec_security->settings, "gensec_krb5", "mutual", true)) {
gensec_krb5_state->ap_req_options |= AP_OPTS_MUTUAL_REQUIRED;
}
}
principal = gensec_get_target_principal(gensec_security);
ret = cli_credentials_get_ccache(gensec_get_credentials(gensec_security),
gensec_security->event_ctx,
gensec_security->settings->lp_ctx, &ccache_container, &error_string);
switch (ret) {
case 0:
break;
case KRB5KDC_ERR_PREAUTH_FAILED:
case KRB5KDC_ERR_C_PRINCIPAL_UNKNOWN:
return NT_STATUS_LOGON_FAILURE;
case KRB5_KDC_UNREACH:
DEBUG(3, ("Cannot reach a KDC we require to contact %s: %s\n", principal, error_string));
return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
case KRB5_CC_NOTFOUND:
case KRB5_CC_END:
DEBUG(3, ("Error preparing credentials we require to contact %s : %s\n", principal, error_string));
return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
default:
DEBUG(1, ("gensec_krb5_start: Aquiring initiator credentials failed: %s\n", error_string));
return NT_STATUS_UNSUCCESSFUL;
}
in_data.length = 0;
/* Do this every time, in case we have weird recursive issues here */
ret = smb_krb5_context_set_event_ctx(gensec_krb5_state->smb_krb5_context, gensec_security->event_ctx, &previous_ev);
if (ret != 0) {
DEBUG(1, ("gensec_krb5_start: Setting event context failed\n"));
return NT_STATUS_NO_MEMORY;
}
if (principal) {
krb5_principal target_principal;
ret = krb5_parse_name(gensec_krb5_state->smb_krb5_context->krb5_context, principal,
&target_principal);
if (ret == 0) {
ret = krb5_mk_req_exact(gensec_krb5_state->smb_krb5_context->krb5_context,
&gensec_krb5_state->auth_context,
gensec_krb5_state->ap_req_options,
target_principal,
&in_data, ccache_container->ccache,
&gensec_krb5_state->enc_ticket);
krb5_free_principal(gensec_krb5_state->smb_krb5_context->krb5_context,
target_principal);
}
} else {
ret = krb5_mk_req(gensec_krb5_state->smb_krb5_context->krb5_context,
&gensec_krb5_state->auth_context,
gensec_krb5_state->ap_req_options,
gensec_get_target_service(gensec_security),
hostname,
&in_data, ccache_container->ccache,
&gensec_krb5_state->enc_ticket);
}
smb_krb5_context_remove_event_ctx(gensec_krb5_state->smb_krb5_context, previous_ev, gensec_security->event_ctx);
switch (ret) {
case 0:
return NT_STATUS_OK;
case KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN:
DEBUG(3, ("Server [%s] is not registered with our KDC: %s\n",
hostname, smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state)));
return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
case KRB5_KDC_UNREACH:
DEBUG(3, ("Cannot reach a KDC we require to contact host [%s]: %s\n",
hostname, smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state)));
return NT_STATUS_INVALID_PARAMETER; /* Make SPNEGO ignore us, we can't go any further here */
case KRB5KDC_ERR_PREAUTH_FAILED:
case KRB5KRB_AP_ERR_TKT_EXPIRED:
case KRB5_CC_END:
/* Too much clock skew - we will need to kinit to re-skew the clock */
case KRB5KRB_AP_ERR_SKEW:
case KRB5_KDCREP_SKEW:
{
DEBUG(3, ("kerberos (mk_req) failed: %s\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state)));
/*fall through*/
}
/* just don't print a message for these really ordinary messages */
case KRB5_FCC_NOFILE:
case KRB5_CC_NOTFOUND:
case ENOENT:
return NT_STATUS_UNSUCCESSFUL;
break;
default:
DEBUG(0, ("kerberos: %s\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, gensec_krb5_state)));
return NT_STATUS_UNSUCCESSFUL;
}
}
static NTSTATUS gensec_krb5_client_start(struct gensec_security *gensec_security)
{
return gensec_krb5_common_client_start(gensec_security, false);
}
static NTSTATUS gensec_fake_gssapi_krb5_client_start(struct gensec_security *gensec_security)
{
return gensec_krb5_common_client_start(gensec_security, true);
}
/**
* Check if the packet is one for this mechansim
*
* @param gensec_security GENSEC state
* @param in The request, as a DATA_BLOB
* @return Error, INVALID_PARAMETER if it's not a packet for us
* or NT_STATUS_OK if the packet is ok.
*/
static NTSTATUS gensec_fake_gssapi_krb5_magic(struct gensec_security *gensec_security,
const DATA_BLOB *in)
{
if (gensec_gssapi_check_oid(in, GENSEC_OID_KERBEROS5)) {
return NT_STATUS_OK;
} else {
return NT_STATUS_INVALID_PARAMETER;
}
}
/**
* Next state function for the Krb5 GENSEC mechanism
*
* @param gensec_krb5_state KRB5 State
* @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
* @param in The request, as a DATA_BLOB
* @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
* @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
* or NT_STATUS_OK if the user is authenticated.
*/
static NTSTATUS gensec_krb5_update(struct gensec_security *gensec_security,
TALLOC_CTX *out_mem_ctx,
const DATA_BLOB in, DATA_BLOB *out)
{
struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data;
krb5_error_code ret = 0;
NTSTATUS nt_status;
switch (gensec_krb5_state->state_position) {
case GENSEC_KRB5_CLIENT_START:
{
DATA_BLOB unwrapped_out;
if (gensec_krb5_state->gssapi) {
unwrapped_out = data_blob_talloc(out_mem_ctx, gensec_krb5_state->enc_ticket.data, gensec_krb5_state->enc_ticket.length);
/* wrap that up in a nice GSS-API wrapping */
*out = gensec_gssapi_gen_krb5_wrap(out_mem_ctx, &unwrapped_out, TOK_ID_KRB_AP_REQ);
} else {
*out = data_blob_talloc(out_mem_ctx, gensec_krb5_state->enc_ticket.data, gensec_krb5_state->enc_ticket.length);
}
if (gensec_krb5_state->ap_req_options & AP_OPTS_MUTUAL_REQUIRED) {
gensec_krb5_state->state_position = GENSEC_KRB5_CLIENT_MUTUAL_AUTH;
nt_status = NT_STATUS_MORE_PROCESSING_REQUIRED;
} else {
gensec_krb5_state->state_position = GENSEC_KRB5_DONE;
nt_status = NT_STATUS_OK;
}
return nt_status;
}
case GENSEC_KRB5_CLIENT_MUTUAL_AUTH:
{
DATA_BLOB unwrapped_in;
krb5_data inbuf;
krb5_ap_rep_enc_part *repl = NULL;
uint8_t tok_id[2];
if (gensec_krb5_state->gssapi) {
if (!gensec_gssapi_parse_krb5_wrap(out_mem_ctx, &in, &unwrapped_in, tok_id)) {
DEBUG(1,("gensec_gssapi_parse_krb5_wrap(mutual authentication) failed to parse\n"));
dump_data_pw("Mutual authentication message:\n", in.data, in.length);
return NT_STATUS_INVALID_PARAMETER;
}
} else {
unwrapped_in = in;
}
/* TODO: check the tok_id */
inbuf.data = unwrapped_in.data;
inbuf.length = unwrapped_in.length;
ret = krb5_rd_rep(gensec_krb5_state->smb_krb5_context->krb5_context,
gensec_krb5_state->auth_context,
&inbuf, &repl);
if (ret) {
DEBUG(1,("krb5_rd_rep (mutual authentication) failed (%s)\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context, ret, out_mem_ctx)));
dump_data_pw("Mutual authentication message:\n", (uint8_t *)inbuf.data, inbuf.length);
nt_status = NT_STATUS_ACCESS_DENIED;
} else {
*out = data_blob(NULL, 0);
nt_status = NT_STATUS_OK;
gensec_krb5_state->state_position = GENSEC_KRB5_DONE;
}
if (repl) {
krb5_free_ap_rep_enc_part(gensec_krb5_state->smb_krb5_context->krb5_context, repl);
}
return nt_status;
}
case GENSEC_KRB5_SERVER_START:
{
DATA_BLOB unwrapped_in;
DATA_BLOB unwrapped_out = data_blob(NULL, 0);
krb5_data inbuf, outbuf;
uint8_t tok_id[2];
struct keytab_container *keytab;
krb5_principal server_in_keytab;
const char *error_string;
enum credentials_obtained obtained;
if (!in.data) {
return NT_STATUS_INVALID_PARAMETER;
}
/* Grab the keytab, however generated */
ret = cli_credentials_get_keytab(gensec_get_credentials(gensec_security),
gensec_security->settings->lp_ctx, &keytab);
if (ret) {
return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
}
/* This ensures we lookup the correct entry in that keytab */
ret = principal_from_credentials(out_mem_ctx, gensec_get_credentials(gensec_security),
gensec_krb5_state->smb_krb5_context,
&server_in_keytab, &obtained, &error_string);
if (ret) {
DEBUG(2,("Failed to make credentials from principal: %s\n", error_string));
return NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
}
/* Parse the GSSAPI wrapping, if it's there... (win2k3 allows it to be omited) */
if (gensec_krb5_state->gssapi
&& gensec_gssapi_parse_krb5_wrap(out_mem_ctx, &in, &unwrapped_in, tok_id)) {
inbuf.data = unwrapped_in.data;
inbuf.length = unwrapped_in.length;
} else {
inbuf.data = in.data;
inbuf.length = in.length;
}
ret = smb_rd_req_return_stuff(gensec_krb5_state->smb_krb5_context->krb5_context,
&gensec_krb5_state->auth_context,
&inbuf, keytab->keytab, server_in_keytab,
&outbuf,
&gensec_krb5_state->ticket,
&gensec_krb5_state->keyblock);
if (ret) {
return NT_STATUS_LOGON_FAILURE;
}
unwrapped_out.data = (uint8_t *)outbuf.data;
unwrapped_out.length = outbuf.length;
gensec_krb5_state->state_position = GENSEC_KRB5_DONE;
/* wrap that up in a nice GSS-API wrapping */
if (gensec_krb5_state->gssapi) {
*out = gensec_gssapi_gen_krb5_wrap(out_mem_ctx, &unwrapped_out, TOK_ID_KRB_AP_REP);
} else {
*out = data_blob_talloc(out_mem_ctx, outbuf.data, outbuf.length);
}
krb5_data_free(&outbuf);
return NT_STATUS_OK;
}
case GENSEC_KRB5_DONE:
default:
/* Asking too many times... */
return NT_STATUS_INVALID_PARAMETER;
}
}
static NTSTATUS gensec_krb5_session_key(struct gensec_security *gensec_security,
DATA_BLOB *session_key)
{
struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data;
krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context;
krb5_auth_context auth_context = gensec_krb5_state->auth_context;
krb5_keyblock *skey;
krb5_error_code err = -1;
if (gensec_krb5_state->state_position != GENSEC_KRB5_DONE) {
return NT_STATUS_NO_USER_SESSION_KEY;
}
if (gensec_krb5_state->session_key.data) {
*session_key = gensec_krb5_state->session_key;
return NT_STATUS_OK;
}
switch (gensec_security->gensec_role) {
case GENSEC_CLIENT:
err = krb5_auth_con_getlocalsubkey(context, auth_context, &skey);
break;
case GENSEC_SERVER:
err = krb5_auth_con_getremotesubkey(context, auth_context, &skey);
break;
}
if (err == 0 && skey != NULL) {
DEBUG(10, ("Got KRB5 session key of length %d\n",
(int)KRB5_KEY_LENGTH(skey)));
gensec_krb5_state->session_key = data_blob_talloc(gensec_krb5_state,
KRB5_KEY_DATA(skey), KRB5_KEY_LENGTH(skey));
*session_key = gensec_krb5_state->session_key;
dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
krb5_free_keyblock(context, skey);
return NT_STATUS_OK;
} else {
DEBUG(10, ("KRB5 error getting session key %d\n", err));
return NT_STATUS_NO_USER_SESSION_KEY;
}
}
static NTSTATUS gensec_krb5_session_info(struct gensec_security *gensec_security,
struct auth_session_info **_session_info)
{
NTSTATUS nt_status = NT_STATUS_UNSUCCESSFUL;
struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data;
krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context;
struct auth_user_info_dc *user_info_dc = NULL;
struct auth_session_info *session_info = NULL;
struct PAC_LOGON_INFO *logon_info;
krb5_principal client_principal;
char *principal_string;
DATA_BLOB pac;
krb5_data pac_data;
krb5_error_code ret;
TALLOC_CTX *mem_ctx = talloc_new(gensec_security);
if (!mem_ctx) {
return NT_STATUS_NO_MEMORY;
}
ret = krb5_ticket_get_client(context, gensec_krb5_state->ticket, &client_principal);
if (ret) {
DEBUG(5, ("krb5_ticket_get_client failed to get cleint principal: %s\n",
smb_get_krb5_error_message(context,
ret, mem_ctx)));
talloc_free(mem_ctx);
return NT_STATUS_NO_MEMORY;
}
ret = krb5_unparse_name(gensec_krb5_state->smb_krb5_context->krb5_context,
client_principal, &principal_string);
if (ret) {
DEBUG(1, ("Unable to parse client principal: %s\n",
smb_get_krb5_error_message(context,
ret, mem_ctx)));
krb5_free_principal(context, client_principal);
talloc_free(mem_ctx);
return NT_STATUS_NO_MEMORY;
}
ret = krb5_ticket_get_authorization_data_type(context, gensec_krb5_state->ticket,
KRB5_AUTHDATA_WIN2K_PAC,
&pac_data);
if (ret && gensec_setting_bool(gensec_security->settings, "gensec", "require_pac", false)) {
DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access: %s \n",
principal_string,
smb_get_krb5_error_message(context,
ret, mem_ctx)));
free(principal_string);
krb5_free_principal(context, client_principal);
talloc_free(mem_ctx);
return NT_STATUS_ACCESS_DENIED;
} else if (ret) {
/* NO pac */
DEBUG(5, ("krb5_ticket_get_authorization_data_type failed to find PAC: %s\n",
smb_get_krb5_error_message(context,
ret, mem_ctx)));
if (gensec_security->auth_context &&
!gensec_setting_bool(gensec_security->settings, "gensec", "require_pac", false)) {
DEBUG(1, ("Unable to find PAC for %s, resorting to local user lookup: %s",
principal_string, smb_get_krb5_error_message(context,
ret, mem_ctx)));
nt_status = gensec_security->auth_context->get_user_info_dc_principal(mem_ctx,
gensec_security->auth_context,
principal_string,
NULL, &user_info_dc);
if (!NT_STATUS_IS_OK(nt_status)) {
free(principal_string);
krb5_free_principal(context, client_principal);
talloc_free(mem_ctx);
return nt_status;
}
} else {
DEBUG(1, ("Unable to find PAC in ticket from %s, failing to allow access\n",
principal_string));
free(principal_string);
krb5_free_principal(context, client_principal);
talloc_free(mem_ctx);
return NT_STATUS_ACCESS_DENIED;
}
} else {
/* Found pac */
union netr_Validation validation;
pac = data_blob_talloc(mem_ctx, pac_data.data, pac_data.length);
if (!pac.data) {
free(principal_string);
krb5_free_principal(context, client_principal);
talloc_free(mem_ctx);
return NT_STATUS_NO_MEMORY;
}
/* decode and verify the pac */
nt_status = kerberos_pac_logon_info(gensec_krb5_state,
&logon_info, pac,
gensec_krb5_state->smb_krb5_context->krb5_context,
NULL, gensec_krb5_state->keyblock,
client_principal,
gensec_krb5_state->ticket->ticket.authtime, NULL);
if (!NT_STATUS_IS_OK(nt_status)) {
free(principal_string);
krb5_free_principal(context, client_principal);
talloc_free(mem_ctx);
return nt_status;
}
validation.sam3 = &logon_info->info3;
nt_status = make_user_info_dc_netlogon_validation(mem_ctx,
NULL,
3, &validation,
&user_info_dc);
if (!NT_STATUS_IS_OK(nt_status)) {
free(principal_string);
krb5_free_principal(context, client_principal);
talloc_free(mem_ctx);
return nt_status;
}
}
free(principal_string);
krb5_free_principal(context, client_principal);
/* references the user_info_dc into the session_info */
nt_status = gensec_generate_session_info(mem_ctx, gensec_security, user_info_dc, &session_info);
if (!NT_STATUS_IS_OK(nt_status)) {
talloc_free(mem_ctx);
return nt_status;
}
nt_status = gensec_krb5_session_key(gensec_security, &session_info->session_key);
if (!NT_STATUS_IS_OK(nt_status)) {
talloc_free(mem_ctx);
return nt_status;
}
*_session_info = session_info;
talloc_steal(gensec_krb5_state, session_info);
talloc_free(mem_ctx);
return NT_STATUS_OK;
}
static NTSTATUS gensec_krb5_wrap(struct gensec_security *gensec_security,
TALLOC_CTX *mem_ctx,
const DATA_BLOB *in,
DATA_BLOB *out)
{
struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data;
krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context;
krb5_auth_context auth_context = gensec_krb5_state->auth_context;
krb5_error_code ret;
krb5_data input, output;
input.length = in->length;
input.data = in->data;
if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
ret = krb5_mk_priv(context, auth_context, &input, &output, NULL);
if (ret) {
DEBUG(1, ("krb5_mk_priv failed: %s\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context,
ret, mem_ctx)));
return NT_STATUS_ACCESS_DENIED;
}
*out = data_blob_talloc(mem_ctx, output.data, output.length);
krb5_data_free(&output);
} else {
return NT_STATUS_ACCESS_DENIED;
}
return NT_STATUS_OK;
}
static NTSTATUS gensec_krb5_unwrap(struct gensec_security *gensec_security,
TALLOC_CTX *mem_ctx,
const DATA_BLOB *in,
DATA_BLOB *out)
{
struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data;
krb5_context context = gensec_krb5_state->smb_krb5_context->krb5_context;
krb5_auth_context auth_context = gensec_krb5_state->auth_context;
krb5_error_code ret;
krb5_data input, output;
krb5_replay_data replay;
input.length = in->length;
input.data = in->data;
if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
ret = krb5_rd_priv(context, auth_context, &input, &output, &replay);
if (ret) {
DEBUG(1, ("krb5_rd_priv failed: %s\n",
smb_get_krb5_error_message(gensec_krb5_state->smb_krb5_context->krb5_context,
ret, mem_ctx)));
return NT_STATUS_ACCESS_DENIED;
}
*out = data_blob_talloc(mem_ctx, output.data, output.length);
krb5_data_free(&output);
} else {
return NT_STATUS_ACCESS_DENIED;
}
return NT_STATUS_OK;
}
static bool gensec_krb5_have_feature(struct gensec_security *gensec_security,
uint32_t feature)
{
struct gensec_krb5_state *gensec_krb5_state = (struct gensec_krb5_state *)gensec_security->private_data;
if (feature & GENSEC_FEATURE_SESSION_KEY) {
return true;
}
if (!gensec_krb5_state->gssapi &&
(feature & GENSEC_FEATURE_SEAL)) {
return true;
}
return false;
}
static const char *gensec_krb5_oids[] = {
GENSEC_OID_KERBEROS5,
GENSEC_OID_KERBEROS5_OLD,
NULL
};
static const struct gensec_security_ops gensec_fake_gssapi_krb5_security_ops = {
.name = "fake_gssapi_krb5",
.auth_type = DCERPC_AUTH_TYPE_KRB5,
.oid = gensec_krb5_oids,
.client_start = gensec_fake_gssapi_krb5_client_start,
.server_start = gensec_fake_gssapi_krb5_server_start,
.update = gensec_krb5_update,
.magic = gensec_fake_gssapi_krb5_magic,
.session_key = gensec_krb5_session_key,
.session_info = gensec_krb5_session_info,
.have_feature = gensec_krb5_have_feature,
.enabled = false,
.kerberos = true,
.priority = GENSEC_KRB5
};
static const struct gensec_security_ops gensec_krb5_security_ops = {
.name = "krb5",
.client_start = gensec_krb5_client_start,
.server_start = gensec_krb5_server_start,
.update = gensec_krb5_update,
.session_key = gensec_krb5_session_key,
.session_info = gensec_krb5_session_info,
.have_feature = gensec_krb5_have_feature,
.wrap = gensec_krb5_wrap,
.unwrap = gensec_krb5_unwrap,
.enabled = true,
.kerberos = true,
.priority = GENSEC_KRB5
};
_PUBLIC_ NTSTATUS gensec_krb5_init(void)
{
NTSTATUS ret;
ret = gensec_register(&gensec_krb5_security_ops);
if (!NT_STATUS_IS_OK(ret)) {
DEBUG(0,("Failed to register '%s' gensec backend!\n",
gensec_krb5_security_ops.name));
return ret;
}
ret = gensec_register(&gensec_fake_gssapi_krb5_security_ops);
if (!NT_STATUS_IS_OK(ret)) {
DEBUG(0,("Failed to register '%s' gensec backend!\n",
gensec_krb5_security_ops.name));
return ret;
}
return ret;
}
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