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;
}
}
BOOL get_krb5_smb_session_key(krb5_context context, krb5_auth_context auth_context, DATA_BLOB *session_key, BOOL remote)
{
krb5_keyblock *skey;
krb5_error_code err;
BOOL ret = False;
if (remote)
err = krb5_auth_con_getremotesubkey(context, auth_context, &skey);
else
err = krb5_auth_con_getlocalsubkey(context, auth_context, &skey);
if (err == 0 && skey != NULL) {
DEBUG(10, ("Got KRB5 session key of length %d\n", (int)KRB5_KEY_LENGTH(skey)));
*session_key = data_blob(KRB5_KEY_DATA(skey), KRB5_KEY_LENGTH(skey));
dump_data_pw("KRB5 Session Key:\n", session_key->data, session_key->length);
ret = True;
krb5_free_keyblock(context, skey);
} else {
DEBUG(10, ("KRB5 error getting session key %d\n", err));
}
return ret;
}
static krb5_error_code
tgs_parse_request(krb5_context context,
krb5_kdc_configuration *config,
KDC_REQ_BODY *b,
const PA_DATA *tgs_req,
hdb_entry_ex **krbtgt,
krb5_enctype *krbtgt_etype,
krb5_ticket **ticket,
const char **e_text,
const char *from,
const struct sockaddr *from_addr,
time_t **csec,
int **cusec,
AuthorizationData **auth_data)
{
krb5_ap_req ap_req;
krb5_error_code ret;
krb5_principal princ;
krb5_auth_context ac = NULL;
krb5_flags ap_req_options;
krb5_flags verify_ap_req_flags;
krb5_crypto crypto;
Key *tkey;
*auth_data = NULL;
*csec = NULL;
*cusec = NULL;
memset(&ap_req, 0, sizeof(ap_req));
ret = krb5_decode_ap_req(context, &tgs_req->padata_value, &ap_req);
if(ret){
kdc_log(context, config, 0, "Failed to decode AP-REQ: %s",
krb5_get_err_text(context, ret));
goto out;
}
if(!get_krbtgt_realm(&ap_req.ticket.sname)){
/* XXX check for ticket.sname == req.sname */
kdc_log(context, config, 0, "PA-DATA is not a ticket-granting ticket");
ret = KRB5KDC_ERR_POLICY; /* ? */
goto out;
}
_krb5_principalname2krb5_principal(context,
&princ,
ap_req.ticket.sname,
ap_req.ticket.realm);
ret = _kdc_db_fetch(context, config, princ, HDB_F_GET_KRBTGT, NULL, krbtgt);
if(ret) {
char *p;
ret = krb5_unparse_name(context, princ, &p);
if (ret != 0)
p = "<unparse_name failed>";
krb5_free_principal(context, princ);
kdc_log(context, config, 0,
"Ticket-granting ticket not found in database: %s: %s",
p, krb5_get_err_text(context, ret));
if (ret == 0)
free(p);
ret = KRB5KRB_AP_ERR_NOT_US;
goto out;
}
if(ap_req.ticket.enc_part.kvno &&
*ap_req.ticket.enc_part.kvno != (*krbtgt)->entry.kvno){
char *p;
ret = krb5_unparse_name (context, princ, &p);
krb5_free_principal(context, princ);
if (ret != 0)
p = "<unparse_name failed>";
kdc_log(context, config, 0,
"Ticket kvno = %d, DB kvno = %d (%s)",
*ap_req.ticket.enc_part.kvno,
(*krbtgt)->entry.kvno,
p);
if (ret == 0)
free (p);
ret = KRB5KRB_AP_ERR_BADKEYVER;
goto out;
}
*krbtgt_etype = ap_req.ticket.enc_part.etype;
ret = hdb_enctype2key(context, &(*krbtgt)->entry,
ap_req.ticket.enc_part.etype, &tkey);
if(ret){
char *str, *p;
krb5_enctype_to_string(context, ap_req.ticket.enc_part.etype, &str);
krb5_unparse_name(context, princ, &p);
kdc_log(context, config, 0,
"No server key with enctype %s found for %s", str, p);
free(str);
free(p);
ret = KRB5KRB_AP_ERR_BADKEYVER;
goto out;
}
if (b->kdc_options.validate)
verify_ap_req_flags = KRB5_VERIFY_AP_REQ_IGNORE_INVALID;
else
verify_ap_req_flags = 0;
ret = krb5_verify_ap_req2(context,
&ac,
&ap_req,
princ,
&tkey->key,
verify_ap_req_flags,
&ap_req_options,
ticket,
KRB5_KU_TGS_REQ_AUTH);
krb5_free_principal(context, princ);
if(ret) {
kdc_log(context, config, 0, "Failed to verify AP-REQ: %s",
krb5_get_err_text(context, ret));
goto out;
}
{
krb5_authenticator auth;
ret = krb5_auth_con_getauthenticator(context, ac, &auth);
if (ret == 0) {
*csec = malloc(sizeof(**csec));
if (*csec == NULL) {
krb5_free_authenticator(context, &auth);
kdc_log(context, config, 0, "malloc failed");
goto out;
}
**csec = auth->ctime;
*cusec = malloc(sizeof(**cusec));
if (*cusec == NULL) {
krb5_free_authenticator(context, &auth);
kdc_log(context, config, 0, "malloc failed");
goto out;
}
**cusec = auth->cusec;
krb5_free_authenticator(context, &auth);
}
}
ret = tgs_check_authenticator(context, config,
ac, b, e_text, &(*ticket)->ticket.key);
if (ret) {
krb5_auth_con_free(context, ac);
goto out;
}
if (b->enc_authorization_data) {
krb5_keyblock *subkey;
krb5_data ad;
ret = krb5_auth_con_getremotesubkey(context,
ac,
&subkey);
if(ret){
krb5_auth_con_free(context, ac);
kdc_log(context, config, 0, "Failed to get remote subkey: %s",
krb5_get_err_text(context, ret));
goto out;
}
if(subkey == NULL){
ret = krb5_auth_con_getkey(context, ac, &subkey);
if(ret) {
krb5_auth_con_free(context, ac);
kdc_log(context, config, 0, "Failed to get session key: %s",
krb5_get_err_text(context, ret));
goto out;
}
}
if(subkey == NULL){
krb5_auth_con_free(context, ac);
kdc_log(context, config, 0,
"Failed to get key for enc-authorization-data");
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */
goto out;
}
ret = krb5_crypto_init(context, subkey, 0, &crypto);
if (ret) {
krb5_auth_con_free(context, ac);
kdc_log(context, config, 0, "krb5_crypto_init failed: %s",
krb5_get_err_text(context, ret));
goto out;
}
ret = krb5_decrypt_EncryptedData (context,
crypto,
KRB5_KU_TGS_REQ_AUTH_DAT_SUBKEY,
b->enc_authorization_data,
&ad);
krb5_crypto_destroy(context, crypto);
if(ret){
krb5_auth_con_free(context, ac);
kdc_log(context, config, 0,
"Failed to decrypt enc-authorization-data");
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */
goto out;
}
krb5_free_keyblock(context, subkey);
ALLOC(*auth_data);
if (*auth_data == NULL) {
krb5_auth_con_free(context, ac);
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */
goto out;
}
ret = decode_AuthorizationData(ad.data, ad.length, *auth_data, NULL);
if(ret){
krb5_auth_con_free(context, ac);
free(*auth_data);
*auth_data = NULL;
kdc_log(context, config, 0, "Failed to decode authorization data");
ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; /* ? */
goto out;
}
}
krb5_auth_con_free(context, ac);
out:
free_AP_REQ(&ap_req);
return ret;
}
static OM_uint32
gsskrb5_acceptor_start(OM_uint32 * minor_status,
gsskrb5_ctx ctx,
krb5_context context,
const gss_cred_id_t acceptor_cred_handle,
const gss_buffer_t input_token_buffer,
const gss_channel_bindings_t input_chan_bindings,
gss_name_t * src_name,
gss_OID * mech_type,
gss_buffer_t output_token,
OM_uint32 * ret_flags,
OM_uint32 * time_rec,
gss_cred_id_t * delegated_cred_handle)
{
krb5_error_code kret;
OM_uint32 ret = GSS_S_COMPLETE;
krb5_data indata;
krb5_flags ap_options;
krb5_keytab keytab = NULL;
int is_cfx = 0;
const gsskrb5_cred acceptor_cred = (gsskrb5_cred)acceptor_cred_handle;
/*
* We may, or may not, have an escapsulation.
*/
ret = _gsskrb5_decapsulate (minor_status,
input_token_buffer,
&indata,
"\x01\x00",
GSS_KRB5_MECHANISM);
if (ret) {
/* Assume that there is no OID wrapping. */
indata.length = input_token_buffer->length;
indata.data = input_token_buffer->value;
}
/*
* We need to get our keytab
*/
if (acceptor_cred == NULL) {
if (_gsskrb5_keytab != NULL)
keytab = _gsskrb5_keytab;
} else if (acceptor_cred->keytab != NULL) {
keytab = acceptor_cred->keytab;
}
/*
* We need to check the ticket and create the AP-REP packet
*/
{
krb5_rd_req_in_ctx in = NULL;
krb5_rd_req_out_ctx out = NULL;
krb5_principal server = NULL;
if (acceptor_cred)
server = acceptor_cred->principal;
kret = krb5_rd_req_in_ctx_alloc(context, &in);
if (kret == 0)
kret = krb5_rd_req_in_set_keytab(context, in, keytab);
if (kret) {
if (in)
krb5_rd_req_in_ctx_free(context, in);
*minor_status = kret;
return GSS_S_FAILURE;
}
kret = krb5_rd_req_ctx(context,
&ctx->auth_context,
&indata,
server,
in, &out);
krb5_rd_req_in_ctx_free(context, in);
if (kret == KRB5KRB_AP_ERR_SKEW || kret == KRB5KRB_AP_ERR_TKT_NYV) {
/*
* No reply in non-MUTUAL mode, but we don't know that its
* non-MUTUAL mode yet, thats inside the 8003 checksum, so
* lets only send the error token on clock skew, that
* limit when send error token for non-MUTUAL.
*/
return send_error_token(minor_status, context, kret,
server, &indata, output_token);
} else if (kret) {
*minor_status = kret;
return GSS_S_FAILURE;
}
/*
* we need to remember some data on the context_handle.
*/
kret = krb5_rd_req_out_get_ap_req_options(context, out,
&ap_options);
if (kret == 0)
kret = krb5_rd_req_out_get_ticket(context, out,
&ctx->ticket);
if (kret == 0)
kret = krb5_rd_req_out_get_keyblock(context, out,
&ctx->service_keyblock);
ctx->lifetime = ctx->ticket->ticket.endtime;
krb5_rd_req_out_ctx_free(context, out);
if (kret) {
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
}
/*
* We need to copy the principal names to the context and the
* calling layer.
*/
kret = krb5_copy_principal(context,
ctx->ticket->client,
&ctx->source);
if (kret) {
ret = GSS_S_FAILURE;
*minor_status = kret;
}
kret = krb5_copy_principal(context,
ctx->ticket->server,
&ctx->target);
if (kret) {
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
/*
* We need to setup some compat stuff, this assumes that
* context_handle->target is already set.
*/
ret = _gss_DES3_get_mic_compat(minor_status, ctx, context);
if (ret)
return ret;
if (src_name != NULL) {
kret = krb5_copy_principal (context,
ctx->ticket->client,
(gsskrb5_name*)src_name);
if (kret) {
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
}
/*
* We need to get the flags out of the 8003 checksum.
*/
{
krb5_authenticator authenticator;
kret = krb5_auth_con_getauthenticator(context,
ctx->auth_context,
&authenticator);
if(kret) {
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
if (authenticator->cksum == NULL) {
krb5_free_authenticator(context, &authenticator);
*minor_status = 0;
return GSS_S_BAD_BINDINGS;
}
if (authenticator->cksum->cksumtype == CKSUMTYPE_GSSAPI) {
ret = _gsskrb5_verify_8003_checksum(minor_status,
input_chan_bindings,
authenticator->cksum,
&ctx->flags,
&ctx->fwd_data);
krb5_free_authenticator(context, &authenticator);
if (ret) {
return ret;
}
} else {
krb5_crypto crypto;
kret = krb5_crypto_init(context,
ctx->auth_context->keyblock,
0, &crypto);
if(kret) {
krb5_free_authenticator(context, &authenticator);
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
/*
* Windows accepts Samba3's use of a kerberos, rather than
* GSSAPI checksum here
*/
kret = krb5_verify_checksum(context,
crypto, KRB5_KU_AP_REQ_AUTH_CKSUM, NULL, 0,
authenticator->cksum);
krb5_free_authenticator(context, &authenticator);
krb5_crypto_destroy(context, crypto);
if(kret) {
ret = GSS_S_BAD_SIG;
*minor_status = kret;
return ret;
}
/*
* Samba style get some flags (but not DCE-STYLE), use
* ap_options to guess the mutual flag.
*/
ctx->flags = GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG;
if (ap_options & AP_OPTS_MUTUAL_REQUIRED)
ctx->flags |= GSS_C_MUTUAL_FLAG;
}
}
if(ctx->flags & GSS_C_MUTUAL_FLAG) {
krb5_data outbuf;
int use_subkey = 0;
_gsskrb5i_is_cfx(context, ctx, 1);
is_cfx = (ctx->more_flags & IS_CFX);
if (is_cfx || (ap_options & AP_OPTS_USE_SUBKEY)) {
use_subkey = 1;
} else {
krb5_keyblock *rkey;
/*
* If there is a initiator subkey, copy that to acceptor
* subkey to match Windows behavior
*/
kret = krb5_auth_con_getremotesubkey(context,
ctx->auth_context,
&rkey);
if (kret == 0) {
kret = krb5_auth_con_setlocalsubkey(context,
ctx->auth_context,
rkey);
if (kret == 0)
use_subkey = 1;
krb5_free_keyblock(context, rkey);
}
}
if (use_subkey) {
ctx->more_flags |= ACCEPTOR_SUBKEY;
krb5_auth_con_addflags(context, ctx->auth_context,
KRB5_AUTH_CONTEXT_USE_SUBKEY,
NULL);
}
kret = krb5_mk_rep(context,
ctx->auth_context,
&outbuf);
if (kret) {
*minor_status = kret;
return GSS_S_FAILURE;
}
if (IS_DCE_STYLE(ctx)) {
output_token->length = outbuf.length;
output_token->value = outbuf.data;
} else {
ret = _gsskrb5_encapsulate(minor_status,
&outbuf,
output_token,
"\x02\x00",
GSS_KRB5_MECHANISM);
krb5_data_free (&outbuf);
if (ret)
return ret;
}
}
ctx->flags |= GSS_C_TRANS_FLAG;
/* Remember the flags */
ctx->lifetime = ctx->ticket->ticket.endtime;
ctx->more_flags |= OPEN;
if (mech_type)
*mech_type = GSS_KRB5_MECHANISM;
if (time_rec) {
ret = _gsskrb5_lifetime_left(minor_status,
context,
ctx->lifetime,
time_rec);
if (ret) {
return ret;
}
}
/*
* When GSS_C_DCE_STYLE is in use, we need ask for a AP-REP from
* the client.
*/
if (IS_DCE_STYLE(ctx)) {
/*
* Return flags to caller, but we haven't processed
* delgations yet
*/
if (ret_flags)
*ret_flags = (ctx->flags & ~GSS_C_DELEG_FLAG);
ctx->state = ACCEPTOR_WAIT_FOR_DCESTYLE;
return GSS_S_CONTINUE_NEEDED;
}
ret = gsskrb5_acceptor_ready(minor_status, ctx, context,
delegated_cred_handle);
if (ret_flags)
*ret_flags = ctx->flags;
return ret;
}
static OM_uint32
repl_mutual
(OM_uint32 * minor_status,
gsskrb5_ctx ctx,
const gss_OID mech_type,
OM_uint32 req_flags,
OM_uint32 time_req,
const gss_channel_bindings_t input_chan_bindings,
const gss_buffer_t input_token,
gss_OID * actual_mech_type,
gss_buffer_t output_token,
OM_uint32 * ret_flags,
OM_uint32 * time_rec
)
{
OM_uint32 ret;
krb5_error_code kret;
krb5_data indata;
krb5_ap_rep_enc_part *repl;
int is_cfx = 0;
output_token->length = 0;
output_token->value = NULL;
if (actual_mech_type)
*actual_mech_type = GSS_KRB5_MECHANISM;
if (ctx->flags & GSS_C_DCE_STYLE) {
/* There is no OID wrapping. */
indata.length = input_token->length;
indata.data = input_token->value;
} else {
ret = _gsskrb5_decapsulate (minor_status,
input_token,
&indata,
"\x02\x00",
GSS_KRB5_MECHANISM);
if (ret) {
/* XXX - Handle AP_ERROR */
return ret;
}
}
kret = krb5_rd_rep (_gsskrb5_context,
ctx->auth_context,
&indata,
&repl);
if (kret) {
_gsskrb5_set_error_string ();
*minor_status = kret;
return GSS_S_FAILURE;
}
krb5_free_ap_rep_enc_part (_gsskrb5_context,
repl);
_gsskrb5i_is_cfx(ctx, &is_cfx);
if (is_cfx) {
krb5_keyblock *key = NULL;
kret = krb5_auth_con_getremotesubkey(_gsskrb5_context,
ctx->auth_context,
&key);
if (kret == 0 && key != NULL) {
ctx->more_flags |= ACCEPTOR_SUBKEY;
krb5_free_keyblock (_gsskrb5_context, key);
}
}
*minor_status = 0;
if (time_rec) {
ret = _gsskrb5_lifetime_left(minor_status,
ctx->lifetime,
time_rec);
} else {
ret = GSS_S_COMPLETE;
}
if (ret_flags)
*ret_flags = ctx->flags;
if (req_flags & GSS_C_DCE_STYLE) {
int32_t con_flags;
krb5_data outbuf;
/* Do don't do sequence number for the mk-rep */
krb5_auth_con_removeflags(_gsskrb5_context,
ctx->auth_context,
KRB5_AUTH_CONTEXT_DO_SEQUENCE,
&con_flags);
kret = krb5_mk_rep(_gsskrb5_context,
ctx->auth_context,
&outbuf);
if (kret) {
_gsskrb5_set_error_string ();
*minor_status = kret;
return GSS_S_FAILURE;
}
output_token->length = outbuf.length;
output_token->value = outbuf.data;
krb5_auth_con_removeflags(_gsskrb5_context,
ctx->auth_context,
KRB5_AUTH_CONTEXT_DO_SEQUENCE,
NULL);
}
return gsskrb5_initiator_ready(minor_status, ctx);
}
static OM_uint32
gsskrb5_acceptor_start(OM_uint32 * minor_status,
gsskrb5_ctx ctx,
krb5_context context,
const gss_cred_id_t acceptor_cred_handle,
const gss_buffer_t input_token_buffer,
const gss_channel_bindings_t input_chan_bindings,
gss_name_t * src_name,
gss_OID * mech_type,
gss_buffer_t output_token,
OM_uint32 * ret_flags,
OM_uint32 * time_rec,
gss_cred_id_t * delegated_cred_handle)
{
krb5_error_code kret;
OM_uint32 ret = GSS_S_COMPLETE;
krb5_data indata;
krb5_flags ap_options;
krb5_keytab keytab = NULL;
int is_cfx = 0;
const gsskrb5_cred acceptor_cred = (gsskrb5_cred)acceptor_cred_handle;
krb5_boolean is_hostbased_service = FALSE;
/*
* We may, or may not, have an escapsulation.
*/
ret = _gsskrb5_decapsulate (minor_status,
input_token_buffer,
&indata,
"\x01\x00",
ctx->mech);
if (ret) {
/* Assume that there is no OID wrapping. */
indata.length = input_token_buffer->length;
indata.data = input_token_buffer->value;
}
/*
* We need to get our keytab
*/
if (acceptor_cred == NULL) {
if (_gsskrb5_keytab != NULL)
keytab = _gsskrb5_keytab;
} else if (acceptor_cred->keytab != NULL) {
keytab = acceptor_cred->keytab;
}
is_hostbased_service =
(acceptor_cred &&
acceptor_cred->principal &&
krb5_principal_is_gss_hostbased_service(context, acceptor_cred->principal));
/*
* We need to check the ticket and create the AP-REP packet
*/
{
krb5_rd_req_in_ctx in = NULL;
krb5_rd_req_out_ctx out = NULL;
krb5_principal server = NULL;
if (acceptor_cred && !is_hostbased_service)
server = acceptor_cred->principal;
kret = krb5_rd_req_in_ctx_alloc(context, &in);
if (kret == 0)
kret = krb5_rd_req_in_set_keytab(context, in, keytab);
if (kret) {
if (in)
krb5_rd_req_in_ctx_free(context, in);
*minor_status = kret;
return GSS_S_FAILURE;
}
kret = krb5_rd_req_ctx(context,
&ctx->auth_context,
&indata,
server,
in, &out);
krb5_rd_req_in_ctx_free(context, in);
if (ret && _gss_mg_log_level(5)) {
const char *e = krb5_get_error_message(context, ret);
char *s = NULL;
if (server)
(void)krb5_unparse_name(context, server, &s);
_gss_mg_log(5, "gss-asc: rd_req (server: %s) failed with: %d: %s",
s ? s : "<not specified>",
ret, e);
krb5_free_error_message(context, e);
if (s)
krb5_xfree(s);
}
switch (kret) {
case 0:
break;
case KRB5KRB_AP_ERR_SKEW:
case KRB5KRB_AP_ERR_TKT_NYV:
/*
* No reply in non-MUTUAL mode, but we don't know that its
* non-MUTUAL mode yet, thats inside the 8003 checksum, so
* lets only send the error token on clock skew, that
* limit when send error token for non-MUTUAL.
*/
return send_error_token(minor_status, context, kret,
server, &indata, ctx->mech, output_token);
case KRB5KRB_AP_ERR_MODIFIED:
case KRB5_KT_NOTFOUND:
case KRB5_KT_END:
/*
* If the error is on the keytab entry missing or bad
* decryption, lets assume that the keytab version was
* wrong and tell the client that.
*/
return send_error_token(minor_status, context, KRB5KRB_AP_ERR_MODIFIED,
server, NULL, ctx->mech, output_token);
default:
*minor_status = kret;
return GSS_S_FAILURE;
}
/*
* we need to remember some data on the context_handle.
*/
kret = krb5_rd_req_out_get_ap_req_options(context, out,
&ap_options);
if (kret == 0)
kret = krb5_rd_req_out_get_ticket(context, out,
&ctx->ticket);
if (kret == 0)
kret = krb5_rd_req_out_get_keyblock(context, out,
&ctx->service_keyblock);
if (kret == 0) {
int flags;
flags = krb5_rd_req_out_get_flags(context, out);
if (flags & KRB5_RD_REQ_OUT_PAC_VALID)
ctx->more_flags |= PAC_VALID;
}
if (kret == 0 && is_hostbased_service) {
krb5_principal sp = ctx->ticket->server;
if (sp->name.name_string.len < 1 ||
strcmp(sp->name.name_string.val[0], acceptor_cred->principal->name.name_string.val[0]) != 0)
{
kret = KRB5KRB_AP_WRONG_PRINC;
krb5_set_error_message(context, ret, "Expecting service %s but got %s",
acceptor_cred->principal->name.name_string.val[0],
sp->name.name_string.val[0]);
}
}
ctx->endtime = ctx->ticket->ticket.endtime;
krb5_rd_req_out_ctx_free(context, out);
if (kret) {
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
}
/*
* We need to copy the principal names to the context and the
* calling layer.
*/
kret = krb5_copy_principal(context,
ctx->ticket->client,
&ctx->source);
if (kret) {
*minor_status = kret;
return GSS_S_FAILURE;
}
kret = krb5_copy_principal(context,
ctx->ticket->server,
&ctx->target);
if (kret) {
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
/*
* We need to setup some compat stuff, this assumes that
* context_handle->target is already set.
*/
ret = _gss_DES3_get_mic_compat(minor_status, ctx, context);
if (ret)
return ret;
if (src_name != NULL) {
kret = krb5_copy_principal (context,
ctx->ticket->client,
(gsskrb5_name*)src_name);
if (kret) {
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
}
/*
* We need to get the flags out of the 8003 checksum.
*/
{
krb5_authenticator authenticator;
kret = krb5_auth_con_getauthenticator(context,
ctx->auth_context,
&authenticator);
if(kret) {
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
if (authenticator->cksum == NULL) {
krb5_free_authenticator(context, &authenticator);
*minor_status = 0;
return GSS_S_BAD_BINDINGS;
}
if (authenticator->cksum->cksumtype == CKSUMTYPE_GSSAPI) {
krb5_data finished_data;
krb5_crypto crypto = NULL;
if (ctx->auth_context->remote_subkey) {
kret = krb5_crypto_init(context,
ctx->auth_context->remote_subkey,
0, &crypto);
if (kret) {
*minor_status = kret;
return GSS_S_FAILURE;
}
}
krb5_data_zero(&finished_data);
ret = _gsskrb5_verify_8003_checksum(minor_status,
context,
crypto,
input_chan_bindings,
authenticator->cksum,
&ctx->flags,
&ctx->fwd_data,
&finished_data);
krb5_free_authenticator(context, &authenticator);
if (ret) {
krb5_crypto_destroy(context, crypto);
return ret;
}
if (finished_data.length) {
GSS_KRB5_FINISHED finished;
krb5_data pkt;
memset(&finished, 0, sizeof(finished));
if (ctx->messages == NULL) {
krb5_crypto_destroy(context, crypto);
krb5_data_free(&finished_data);
*minor_status = 0;
return GSS_S_BAD_SIG;
}
kret = krb5_storage_to_data(ctx->messages, &pkt);
if (kret) {
krb5_crypto_destroy(context, crypto);
krb5_data_free(&finished_data);
*minor_status = kret;
return GSS_S_FAILURE;
}
if (ctx->auth_context->remote_subkey == NULL) {
krb5_crypto_destroy(context, crypto);
krb5_data_free(&finished_data);
krb5_data_free(&pkt);
*minor_status = 0;
return GSS_S_BAD_SIG;
}
kret = decode_GSS_KRB5_FINISHED(finished_data.data,
finished_data.length,
&finished, NULL);
krb5_data_free(&finished_data);
if (kret) {
krb5_crypto_destroy(context, crypto);
krb5_data_free(&pkt);
*minor_status = kret;
return GSS_S_FAILURE;
}
kret = krb5_verify_checksum(context, crypto,
KRB5_KU_FINISHED,
pkt.data, pkt.length,
&finished.gss_mic);
free_GSS_KRB5_FINISHED(&finished);
krb5_data_free(&pkt);
if (kret) {
krb5_crypto_destroy(context, crypto);
*minor_status = kret;
return GSS_S_FAILURE;
}
}
krb5_crypto_destroy(context, crypto);
} else {
krb5_crypto crypto;
kret = krb5_crypto_init(context,
ctx->auth_context->keyblock,
0, &crypto);
if(kret) {
krb5_free_authenticator(context, &authenticator);
ret = GSS_S_FAILURE;
*minor_status = kret;
return ret;
}
/*
* Windows accepts Samba3's use of a kerberos, rather than
* GSSAPI checksum here
*/
kret = krb5_verify_checksum(context,
crypto, KRB5_KU_AP_REQ_AUTH_CKSUM, NULL, 0,
authenticator->cksum);
krb5_free_authenticator(context, &authenticator);
krb5_crypto_destroy(context, crypto);
if(kret) {
ret = GSS_S_BAD_SIG;
*minor_status = kret;
return ret;
}
/*
* Samba style get some flags (but not DCE-STYLE), use
* ap_options to guess the mutual flag.
*/
ctx->flags = GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG;
if (ap_options & AP_OPTS_MUTUAL_REQUIRED)
ctx->flags |= GSS_C_MUTUAL_FLAG;
}
}
if(ctx->flags & GSS_C_MUTUAL_FLAG) {
krb5_data outbuf;
int use_subkey = 0;
_gsskrb5i_is_cfx(context, ctx, 1);
is_cfx = (ctx->more_flags & IS_CFX);
if (is_cfx || (ap_options & AP_OPTS_USE_SUBKEY)) {
use_subkey = 1;
} else {
krb5_keyblock *rkey;
/*
* If there is a initiator subkey, copy that to acceptor
* subkey to match Windows behavior
*/
kret = krb5_auth_con_getremotesubkey(context,
ctx->auth_context,
&rkey);
if (kret == 0) {
kret = krb5_auth_con_setlocalsubkey(context,
ctx->auth_context,
rkey);
if (kret == 0)
use_subkey = 1;
krb5_free_keyblock(context, rkey);
}
}
if (use_subkey) {
ctx->gk5c.flags |= GK5C_ACCEPTOR_SUBKEY;
krb5_auth_con_addflags(context, ctx->auth_context,
KRB5_AUTH_CONTEXT_USE_SUBKEY,
NULL);
}
kret = krb5_mk_rep(context,
ctx->auth_context,
&outbuf);
if (kret) {
*minor_status = kret;
return GSS_S_FAILURE;
}
if (IS_DCE_STYLE(ctx)) {
output_token->length = outbuf.length;
output_token->value = outbuf.data;
} else {
ret = _gsskrb5_encapsulate(minor_status,
&outbuf,
output_token,
"\x02\x00",
ctx->mech);
krb5_data_free (&outbuf);
if (ret)
return ret;
}
}
ctx->flags |= GSS_C_TRANS_FLAG;
/* Remember the flags */
ctx->endtime = ctx->ticket->ticket.endtime;
ctx->more_flags |= OPEN;
if (mech_type)
*mech_type = ctx->mech;
if (time_rec) {
ret = _gsskrb5_lifetime_left(minor_status,
context,
ctx->endtime,
time_rec);
if (ret) {
return ret;
}
}
/*
* When GSS_C_DCE_STYLE is in use, we need ask for a AP-REP from
* the client.
*/
if (IS_DCE_STYLE(ctx)) {
/*
* Return flags to caller, but we haven't processed
* delgations yet
*/
if (ret_flags)
*ret_flags = (ctx->flags & ~GSS_C_DELEG_FLAG);
ctx->acceptor_state = acceptor_wait_for_dcestyle;
return GSS_S_CONTINUE_NEEDED;
}
ret = gsskrb5_acceptor_ready(minor_status, ctx, context,
delegated_cred_handle);
if (ret_flags)
*ret_flags = ctx->flags;
return ret;
}
void
kerberos5_is(Authenticator *ap, unsigned char *data, int cnt)
{
krb5_error_code ret;
krb5_data outbuf;
krb5_keyblock *key_block;
char *name;
krb5_principal server;
krb5_authenticator authenticator;
int zero = 0;
if (cnt-- < 1)
return;
switch (*data++) {
case KRB_AUTH:
auth.data = (char *)data;
auth.length = cnt;
auth_context = NULL;
ret = krb5_auth_con_init (context, &auth_context);
if (ret) {
Data(ap, KRB_REJECT, "krb5_auth_con_init failed", -1);
auth_finished(ap, AUTH_REJECT);
if (auth_debug_mode)
printf("Kerberos V5: krb5_auth_con_init failed (%s)\r\n",
krb5_get_err_text(context, ret));
return;
}
ret = krb5_auth_con_setaddrs_from_fd (context,
auth_context,
&zero);
if (ret) {
Data(ap, KRB_REJECT, "krb5_auth_con_setaddrs_from_fd failed", -1);
auth_finished(ap, AUTH_REJECT);
if (auth_debug_mode)
printf("Kerberos V5: "
"krb5_auth_con_setaddrs_from_fd failed (%s)\r\n",
krb5_get_err_text(context, ret));
return;
}
ret = krb5_sock_to_principal (context,
0,
"host",
KRB5_NT_SRV_HST,
&server);
if (ret) {
Data(ap, KRB_REJECT, "krb5_sock_to_principal failed", -1);
auth_finished(ap, AUTH_REJECT);
if (auth_debug_mode)
printf("Kerberos V5: "
"krb5_sock_to_principal failed (%s)\r\n",
krb5_get_err_text(context, ret));
return;
}
ret = krb5_rd_req(context,
&auth_context,
&auth,
server,
NULL,
NULL,
&ticket);
krb5_free_principal (context, server);
if (ret) {
char *errbuf;
asprintf(&errbuf,
"Read req failed: %s",
krb5_get_err_text(context, ret));
Data(ap, KRB_REJECT, errbuf, -1);
if (auth_debug_mode)
printf("%s\r\n", errbuf);
free (errbuf);
return;
}
ret = krb5_auth_con_getkey(context, auth_context, &key_block);
if (ret) {
Data(ap, KRB_REJECT, "krb5_auth_con_getkey failed", -1);
auth_finished(ap, AUTH_REJECT);
if (auth_debug_mode)
printf("Kerberos V5: "
"krb5_auth_con_getkey failed (%s)\r\n",
krb5_get_err_text(context, ret));
return;
}
ret = krb5_auth_getauthenticator (context,
auth_context,
&authenticator);
if (ret) {
Data(ap, KRB_REJECT, "krb5_auth_getauthenticator failed", -1);
auth_finished(ap, AUTH_REJECT);
if (auth_debug_mode)
printf("Kerberos V5: "
"krb5_auth_getauthenticator failed (%s)\r\n",
krb5_get_err_text(context, ret));
return;
}
if (authenticator->cksum) {
char foo[2];
foo[0] = ap->type;
foo[1] = ap->way;
ret = krb5_verify_checksum (context,
foo,
sizeof(foo),
key_block,
authenticator->cksum);
if (ret) {
Data(ap, KRB_REJECT, "No checksum", -1);
if (auth_debug_mode)
printf ("No checksum\r\n");
krb5_free_authenticator (context,
&authenticator);
return;
}
}
krb5_free_authenticator (context,
&authenticator);
ret = krb5_auth_con_getremotesubkey (context,
auth_context,
&key_block);
if (ret) {
Data(ap, KRB_REJECT, "krb5_auth_con_getremotesubkey failed", -1);
auth_finished(ap, AUTH_REJECT);
if (auth_debug_mode)
printf("Kerberos V5: "
"krb5_auth_con_getremotesubkey failed (%s)\r\n",
krb5_get_err_text(context, ret));
return;
}
if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL) {
ret = krb5_mk_rep(context, &auth_context, &outbuf);
if (ret) {
Data(ap, KRB_REJECT,
"krb5_mk_rep failed", -1);
auth_finished(ap, AUTH_REJECT);
if (auth_debug_mode)
printf("Kerberos V5: "
"krb5_mk_rep failed (%s)\r\n",
krb5_get_err_text(context, ret));
return;
}
Data(ap, KRB_RESPONSE, outbuf.data, outbuf.length);
}
if (krb5_unparse_name(context, ticket->client, &name))
name = 0;
if(UserNameRequested && krb5_kuserok(context,
ticket->client,
UserNameRequested)) {
Data(ap, KRB_ACCEPT, name, name ? -1 : 0);
if (auth_debug_mode) {
printf("Kerberos5 identifies him as ``%s''\r\n",
name ? name : "");
}
if(key_block->keytype == KEYTYPE_DES) {
Session_Key skey;
skey.type = SK_DES;
skey.length = 8;
skey.data = key_block->keyvalue.data;
encrypt_session_key(&skey, 0);
}
} else {
char *msg;
asprintf (&msg, "user `%s' is not authorized to "
"login as `%s'",
name ? name : "<unknown>",
UserNameRequested ? UserNameRequested : "<nobody>");
if (msg == NULL)
Data(ap, KRB_REJECT, NULL, 0);
else {
Data(ap, KRB_REJECT, (void *)msg, -1);
free(msg);
}
}
auth_finished(ap, AUTH_USER);
krb5_free_keyblock_contents(context, key_block);
break;
#ifdef FORWARD
case KRB_FORWARD: {
struct passwd *pwd;
char ccname[1024]; /* XXX */
krb5_data inbuf;
krb5_ccache ccache;
inbuf.data = (char *)data;
inbuf.length = cnt;
pwd = getpwnam (UserNameRequested);
if (pwd == NULL)
break;
snprintf (ccname, sizeof(ccname),
"FILE:/tmp/krb5cc_%u", pwd->pw_uid);
ret = krb5_cc_resolve (context, ccname, &ccache);
if (ret) {
if (auth_debug_mode)
printf ("Kerberos V5: could not get ccache: %s\r\n",
krb5_get_err_text(context, ret));
break;
}
ret = krb5_cc_initialize (context,
ccache,
ticket->client);
if (ret) {
if (auth_debug_mode)
printf ("Kerberos V5: could not init ccache: %s\r\n",
krb5_get_err_text(context, ret));
break;
}
ret = krb5_rd_cred (context,
auth_context,
ccache,
&inbuf);
if(ret) {
char *errbuf;
asprintf (&errbuf,
"Read forwarded creds failed: %s",
krb5_get_err_text (context, ret));
if(errbuf == NULL)
Data(ap, KRB_FORWARD_REJECT, NULL, 0);
else
Data(ap, KRB_FORWARD_REJECT, errbuf, -1);
if (auth_debug_mode)
printf("Could not read forwarded credentials: %s\r\n",
errbuf);
free (errbuf);
} else
Data(ap, KRB_FORWARD_ACCEPT, 0, 0);
chown (ccname + 5, pwd->pw_uid, -1);
if (auth_debug_mode)
printf("Forwarded credentials obtained\r\n");
break;
}
#endif /* FORWARD */
default:
if (auth_debug_mode)
printf("Unknown Kerberos option %d\r\n", data[-1]);
Data(ap, KRB_REJECT, 0, 0);
break;
}
}
static krb5_error_code
digest_request(krb5_context context,
krb5_realm realm,
krb5_ccache ccache,
krb5_key_usage usage,
const DigestReqInner *ireq,
DigestRepInner *irep)
{
DigestREQ req;
DigestREP rep;
krb5_error_code ret;
krb5_data data, data2;
size_t size = 0;
krb5_crypto crypto = NULL;
krb5_auth_context ac = NULL;
krb5_principal principal = NULL;
krb5_ccache id = NULL;
krb5_realm r = NULL;
krb5_data_zero(&data);
krb5_data_zero(&data2);
memset(&req, 0, sizeof(req));
memset(&rep, 0, sizeof(rep));
if (ccache == NULL) {
ret = krb5_cc_default(context, &id);
if (ret)
goto out;
} else
id = ccache;
if (realm == NULL) {
ret = krb5_get_default_realm(context, &r);
if (ret)
goto out;
} else
r = realm;
/*
*
*/
ret = krb5_make_principal(context, &principal,
r, KRB5_DIGEST_NAME, r, NULL);
if (ret)
goto out;
ASN1_MALLOC_ENCODE(DigestReqInner, data.data, data.length,
ireq, &size, ret);
if (ret) {
krb5_set_error_message(context, ret,
N_("Failed to encode digest inner request", ""));
goto out;
}
if (size != data.length)
krb5_abortx(context, "ASN.1 internal encoder error");
ret = krb5_mk_req_exact(context, &ac,
AP_OPTS_USE_SUBKEY|AP_OPTS_MUTUAL_REQUIRED,
principal, NULL, id, &req.apReq);
if (ret)
goto out;
{
krb5_keyblock *key;
ret = krb5_auth_con_getlocalsubkey(context, ac, &key);
if (ret)
goto out;
if (key == NULL) {
ret = EINVAL;
krb5_set_error_message(context, ret,
N_("Digest failed to get local subkey", ""));
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, usage,
data.data, data.length, 0,
&req.innerReq);
if (ret)
goto out;
krb5_data_free(&data);
ASN1_MALLOC_ENCODE(DigestREQ, data.data, data.length,
&req, &size, ret);
if (ret) {
krb5_set_error_message(context, ret,
N_("Failed to encode DigestREQest", ""));
goto out;
}
if (size != data.length)
krb5_abortx(context, "ASN.1 internal encoder error");
ret = krb5_sendto_kdc(context, &data, &r, &data2);
if (ret)
goto out;
ret = decode_DigestREP(data2.data, data2.length, &rep, NULL);
if (ret) {
krb5_set_error_message(context, ret,
N_("Failed to parse digest response", ""));
goto out;
}
{
krb5_ap_rep_enc_part *repl;
ret = krb5_rd_rep(context, ac, &rep.apRep, &repl);
if (ret)
goto out;
krb5_free_ap_rep_enc_part(context, repl);
}
{
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,
N_("Digest reply have no remote subkey", ""));
goto out;
}
krb5_crypto_destroy(context, crypto);
ret = krb5_crypto_init(context, key, 0, &crypto);
krb5_free_keyblock (context, key);
if (ret)
goto out;
}
krb5_data_free(&data);
ret = krb5_decrypt_EncryptedData(context, crypto, usage,
&rep.innerRep, &data);
if (ret)
goto out;
ret = decode_DigestRepInner(data.data, data.length, irep, NULL);
if (ret) {
krb5_set_error_message(context, ret,
N_("Failed to decode digest inner reply", ""));
goto out;
}
out:
if (ccache == NULL && id)
krb5_cc_close(context, id);
if (realm == NULL && r)
free(r);
if (crypto)
krb5_crypto_destroy(context, crypto);
if (ac)
krb5_auth_con_free(context, ac);
if (principal)
krb5_free_principal(context, principal);
krb5_data_free(&data);
krb5_data_free(&data2);
free_DigestREQ(&req);
free_DigestREP(&rep);
return ret;
}
static krb5_error_code
recvauth(int f,
krb5_context krb_context,
unsigned int *valid_checksum,
krb5_ticket **ticket,
int *auth_type,
krb5_principal *client,
int encr_flag,
krb5_keytab keytab)
{
krb5_error_code status = 0;
krb5_auth_context auth_context = NULL;
krb5_rcache rcache;
krb5_authenticator *authenticator;
krb5_data inbuf;
krb5_data auth_version;
*valid_checksum = 0;
if ((status = krb5_auth_con_init(krb_context, &auth_context)))
return (status);
/* Only need remote address for rd_cred() to verify client */
if ((status = krb5_auth_con_genaddrs(krb_context, auth_context, f,
KRB5_AUTH_CONTEXT_GENERATE_REMOTE_FULL_ADDR)))
return (status);
status = krb5_auth_con_getrcache(krb_context, auth_context, &rcache);
if (status)
return (status);
if (!rcache) {
krb5_principal server;
status = krb5_sname_to_principal(krb_context, 0, 0,
KRB5_NT_SRV_HST, &server);
if (status)
return (status);
status = krb5_get_server_rcache(krb_context,
krb5_princ_component(krb_context, server, 0),
&rcache);
krb5_free_principal(krb_context, server);
if (status)
return (status);
status = krb5_auth_con_setrcache(krb_context, auth_context,
rcache);
if (status)
return (status);
}
if ((status = krb5_compat_recvauth(krb_context,
&auth_context,
&f,
NULL, /* Specify daemon principal */
0, /* no flags */
keytab, /* NULL to use v5srvtab */
ticket, /* return ticket */
auth_type, /* authentication system */
&auth_version))) {
if (*auth_type == KRB5_RECVAUTH_V5) {
/*
* clean up before exiting
*/
getstr(f, rusername, sizeof (rusername), "remuser");
getstr(f, lusername, sizeof (lusername), "locuser");
getstr(f, term, sizeof (term), "Terminal type");
}
return (status);
}
getstr(f, lusername, sizeof (lusername), "locuser");
getstr(f, term, sizeof (term), "Terminal type");
kcmd_protocol = KCMD_UNKNOWN_PROTOCOL;
if (auth_version.length != 9 || auth_version.data == NULL) {
syslog(LOG_ERR, "Bad application protocol version length in "
"KRB5 exchange, exiting");
fatal(f, "Bad application version length, exiting.");
}
/*
* Determine which Kerberos CMD protocol was used.
*/
if (strncmp(auth_version.data, "KCMDV0.1", 9) == 0) {
kcmd_protocol = KCMD_OLD_PROTOCOL;
} else if (strncmp(auth_version.data, "KCMDV0.2", 9) == 0) {
kcmd_protocol = KCMD_NEW_PROTOCOL;
} else {
syslog(LOG_ERR, "Unrecognized KCMD protocol (%s), exiting",
(char *)auth_version.data);
fatal(f, "Unrecognized KCMD protocol, exiting");
}
if ((*auth_type == KRB5_RECVAUTH_V5) && chksum_flag &&
kcmd_protocol == KCMD_OLD_PROTOCOL) {
if ((status = krb5_auth_con_getauthenticator(krb_context,
auth_context,
&authenticator)))
return (status);
if (authenticator->checksum) {
struct sockaddr_storage adr;
int adr_length = sizeof (adr);
int buflen;
krb5_data input;
krb5_keyblock key;
char *chksumbuf;
/*
* Define the lenght of the chksum buffer.
* chksum string = "[portnum]:termstr:username"
* The extra 32 is to hold a integer string for
* the portnumber.
*/
buflen = strlen(term) + strlen(lusername) + 32;
chksumbuf = (char *)malloc(buflen);
if (chksumbuf == 0) {
krb5_free_authenticator(krb_context,
authenticator);
fatal(f, "Out of memory error");
}
if (getsockname(f, (struct sockaddr *)&adr,
&adr_length) != 0) {
krb5_free_authenticator(krb_context,
authenticator);
fatal(f, "getsockname error");
}
(void) snprintf(chksumbuf, buflen,
"%u:%s%s",
ntohs(SOCK_PORT(adr)),
term, lusername);
input.data = chksumbuf;
input.length = strlen(chksumbuf);
key.contents = (*ticket)->enc_part2->session->contents;
key.length = (*ticket)->enc_part2->session->length;
status = krb5_c_verify_checksum(krb_context,
&key, 0,
&input,
authenticator->checksum,
valid_checksum);
if (status == 0 && *valid_checksum == 0)
status = KRB5KRB_AP_ERR_BAD_INTEGRITY;
if (chksumbuf)
krb5_xfree(chksumbuf);
if (status) {
krb5_free_authenticator(krb_context,
authenticator);
return (status);
}
}
krb5_free_authenticator(krb_context, authenticator);
}
if ((status = krb5_copy_principal(krb_context,
(*ticket)->enc_part2->client,
client)))
return (status);
/* Get the Unix username of the remote user */
getstr(f, rusername, sizeof (rusername), "remuser");
/* Get the Kerberos principal name string of the remote user */
if ((status = krb5_unparse_name(krb_context, *client, &krusername)))
return (status);
#ifdef DEBUG
syslog(LOG_DEBUG | LOG_AUTH, "rlogind: got krb5 credentials for %s",
(krusername != NULL ? krusername : "******"));
#endif
if (encr_flag) {
status = krb5_auth_con_getremotesubkey(krb_context,
auth_context,
&session_key);
if (status) {
syslog(LOG_ERR, "Error getting KRB5 session "
"subkey, exiting");
fatal(f, "Error getting KRB5 session subkey, exiting");
}
/*
* The "new" protocol requires that a subkey be sent.
*/
if (session_key == NULL &&
kcmd_protocol == KCMD_NEW_PROTOCOL) {
syslog(LOG_ERR, "No KRB5 session subkey sent, exiting");
fatal(f, "No KRB5 session subkey sent, exiting");
}
/*
* The "old" protocol does not permit an authenticator subkey.
* The key is taken from the ticket instead (see below).
*/
if (session_key != NULL &&
kcmd_protocol == KCMD_OLD_PROTOCOL) {
syslog(LOG_ERR, "KRB5 session subkey not permitted "
"with old KCMD protocol, exiting");
fatal(f, "KRB5 session subkey not permitted "
"with old KCMD protocol, exiting");
}
/*
* If no key at this point, use the session key from
* the ticket.
*/
if (session_key == NULL) {
/*
* Save the session key so we can configure the crypto
* module later.
*/
status = krb5_copy_keyblock(krb_context,
(*ticket)->enc_part2->session,
&session_key);
if (status) {
syslog(LOG_ERR, "krb5_copy_keyblock failed");
fatal(f, "krb5_copy_keyblock failed");
}
}
/*
* If session key still cannot be found, we must
* exit because encryption is required here
* when encr_flag (-x) is set.
*/
if (session_key == NULL) {
syslog(LOG_ERR, "Could not find an encryption key,"
"exiting");
fatal(f, "Encryption required but key not found, "
"exiting");
}
}
/*
* Use krb5_read_message to read the principal stuff.
*/
if ((status = krb5_read_message(krb_context, (krb5_pointer)&f,
&inbuf)))
fatal(f, "Error reading krb5 message");
if (inbuf.length) { /* Forwarding being done, read creds */
krb5_creds **creds = NULL;
if (status = krb5_rd_cred(krb_context, auth_context, &inbuf,
&creds, NULL)) {
if (rcache)
(void) krb5_rc_close(krb_context, rcache);
krb5_free_creds(krb_context, *creds);
fatal(f, "Can't get forwarded credentials");
}
/* Store the forwarded creds in the ccache */
if (status = store_forw_creds(krb_context,
creds, *ticket, lusername,
&ccache)) {
if (rcache)
(void) krb5_rc_close(krb_context, rcache);
krb5_free_creds(krb_context, *creds);
fatal(f, "Can't store forwarded credentials");
}
krb5_free_creds(krb_context, *creds);
}
if (rcache)
(void) krb5_rc_close(krb_context, rcache);
return (status);
}
static int
recv_krb5_auth (int s, u_char *buf,
struct sockaddr *thisaddr,
struct sockaddr *thataddr,
char **client_username,
char **server_username,
char **cmd)
{
uint32_t len;
krb5_auth_context auth_context = NULL;
krb5_ticket *ticket;
krb5_error_code status;
krb5_data cksum_data;
krb5_principal server;
char *str;
if (memcmp (buf, "\x00\x00\x00\x13", 4) != 0)
return -1;
len = (buf[0] << 24) | (buf[1] << 16) | (buf[2] << 8) | (buf[3]);
if (net_read(s, buf, len) != len)
syslog_and_die ("reading auth info: %s", strerror(errno));
if (len != sizeof(KRB5_SENDAUTH_VERSION)
|| memcmp (buf, KRB5_SENDAUTH_VERSION, len) != 0)
syslog_and_die ("bad sendauth version: %.8s", buf);
status = krb5_sock_to_principal (context,
s,
"host",
KRB5_NT_SRV_HST,
&server);
if (status)
syslog_and_die ("krb5_sock_to_principal: %s",
krb5_get_err_text(context, status));
status = krb5_recvauth_match_version(context,
&auth_context,
&s,
match_kcmd_version,
NULL,
server,
KRB5_RECVAUTH_IGNORE_VERSION,
NULL,
&ticket);
krb5_free_principal (context, server);
if (status)
syslog_and_die ("krb5_recvauth: %s",
krb5_get_err_text(context, status));
*server_username = read_str (s, USERNAME_SZ, "remote username");
*cmd = read_str (s, ARG_MAX + 1, "command");
*client_username = read_str (s, ARG_MAX + 1, "local username");
if(protocol_version == 2) {
status = krb5_auth_con_getremotesubkey(context, auth_context,
&keyblock);
if(status != 0 || keyblock == NULL)
syslog_and_die("failed to get remote subkey");
} else if(protocol_version == 1) {
status = krb5_auth_con_getkey (context, auth_context, &keyblock);
if(status != 0 || keyblock == NULL)
syslog_and_die("failed to get key");
}
if (status != 0 || keyblock == NULL)
syslog_and_die ("krb5_auth_con_getkey: %s",
krb5_get_err_text(context, status));
status = krb5_crypto_init(context, keyblock, 0, &crypto);
if(status)
syslog_and_die("krb5_crypto_init: %s",
krb5_get_err_text(context, status));
cksum_data.length = asprintf (&str,
"%u:%s%s",
ntohs(socket_get_port (thisaddr)),
*cmd,
*server_username);
if (str == NULL)
syslog_and_die ("asprintf: out of memory");
cksum_data.data = str;
status = krb5_verify_authenticator_checksum(context,
auth_context,
cksum_data.data,
cksum_data.length);
if (status)
syslog_and_die ("krb5_verify_authenticator_checksum: %s",
krb5_get_err_text(context, status));
free (cksum_data.data);
if (strncmp (*client_username, "-u ", 3) == 0) {
do_unique_tkfile = 1;
memmove (*client_username, *client_username + 3,
strlen(*client_username) - 2);
}
if (strncmp (*client_username, "-U ", 3) == 0) {
char *end, *temp_tkfile;
do_unique_tkfile = 1;
if (strncmp (*client_username + 3, "FILE:", 5) == 0) {
temp_tkfile = tkfile;
} else {
strlcpy (tkfile, "FILE:", sizeof(tkfile));
temp_tkfile = tkfile + 5;
}
end = strchr(*client_username + 3,' ');
if (end == NULL)
syslog_and_die("missing argument after -U");
snprintf(temp_tkfile, sizeof(tkfile) - (temp_tkfile - tkfile),
"%.*s",
(int)(end - *client_username - 3),
*client_username + 3);
memmove (*client_username, end + 1, strlen(end+1)+1);
}
kerberos_status = save_krb5_creds (s, auth_context, ticket->client);
if(!krb5_kuserok (context,
ticket->client,
*server_username))
fatal (s, NULL, "Permission denied.");
if (strncmp (*cmd, "-x ", 3) == 0) {
do_encrypt = 1;
memmove (*cmd, *cmd + 3, strlen(*cmd) - 2);
} else {
if(do_encrypt)
fatal (s, NULL, "Encryption is required.");
do_encrypt = 0;
}
{
char *name;
if (krb5_unparse_name (context, ticket->client, &name) == 0) {
char addr_str[256];
if (inet_ntop (thataddr->sa_family,
socket_get_address (thataddr),
addr_str, sizeof(addr_str)) == NULL)
strlcpy (addr_str, "unknown address",
sizeof(addr_str));
syslog(LOG_INFO|LOG_AUTH,
"kerberos v5 shell from %s on %s as %s, cmd '%.80s'",
name,
addr_str,
*server_username,
*cmd);
free (name);
}
}
krb5_auth_con_free(context, auth_context);
return 0;
}
int
kerberos5_is_auth (TN_Authenticator * ap, unsigned char *data, int cnt,
char *errbuf, int errbuflen)
{
int r = 0;
krb5_keytab keytabid = 0;
krb5_authenticator *authenticator;
char *name;
krb5_data outbuf;
krb5_keyblock *newkey = NULL;
krb5_principal server;
# ifdef ENCRYPTION
Session_Key skey;
# endif
auth.data = (char *) data;
auth.length = cnt;
if (!r && !auth_context)
r = krb5_auth_con_init (telnet_context, &auth_context);
if (!r)
{
krb5_rcache rcache;
r = krb5_auth_con_getrcache (telnet_context, auth_context, &rcache);
if (!r && !rcache)
{
r = krb5_sname_to_principal (telnet_context, 0, 0,
KRB5_NT_SRV_HST, &server);
if (!r)
{
r = krb5_get_server_rcache (telnet_context,
krb5_princ_component
(telnet_context, server, 0),
&rcache);
krb5_free_principal (telnet_context, server);
}
}
if (!r)
r = krb5_auth_con_setrcache (telnet_context, auth_context, rcache);
}
if (!r && telnet_srvtab)
r = krb5_kt_resolve (telnet_context, telnet_srvtab, &keytabid);
if (!r)
r = krb5_rd_req (telnet_context, &auth_context, &auth,
NULL, keytabid, NULL, &ticket);
if (r)
{
snprintf (errbuf, errbuflen, "krb5_rd_req failed: %s",
error_message (r));
return r;
}
/* 256 bytes should be much larger than any reasonable
first component of a service name especially since
the default is of length 4. */
if (krb5_princ_component (telnet_context, ticket->server, 0)->length < 256)
{
char princ[256];
strncpy (princ,
krb5_princ_component (telnet_context, ticket->server, 0)->data,
krb5_princ_component (telnet_context, ticket->server,
0)->length);
princ[krb5_princ_component (telnet_context, ticket->server, 0)->
length] = '\0';
if (strcmp ("host", princ))
{
snprintf (errbuf, errbuflen,
"incorrect service name: \"%s\" != \"host\"", princ);
return 1;
}
}
else
{
strncpy (errbuf, "service name too long", errbuflen);
return 1;
}
r = krb5_auth_con_getauthenticator (telnet_context,
auth_context, &authenticator);
if (r)
{
snprintf (errbuf, errbuflen,
"krb5_auth_con_getauthenticator failed: %s",
error_message (r));
return 1;
}
# ifdef AUTH_ENCRYPT_MASK
if ((ap->way & AUTH_ENCRYPT_MASK) == AUTH_ENCRYPT_ON
&& !authenticator->checksum)
{
snprintf (errbuf, errbuflen,
"authenticator is missing required checksum");
return 1;
}
# endif
if (authenticator->checksum)
{
char type_check[2];
krb5_checksum *cksum = authenticator->checksum;
krb5_keyblock *key;
type_check[0] = ap->type;
type_check[1] = ap->way;
r = krb5_auth_con_getkey (telnet_context, auth_context, &key);
if (r)
{
snprintf (errbuf, errbuflen,
"krb5_auth_con_getkey failed: %s", error_message (r));
return 1;
}
r = krb5_verify_checksum (telnet_context,
cksum->checksum_type, cksum,
&type_check, 2, key->contents, key->length);
if (r)
{
snprintf (errbuf, errbuflen,
"checksum verification failed: %s", error_message (r));
return 1;
}
krb5_free_keyblock (telnet_context, key);
}
krb5_free_authenticator (telnet_context, authenticator);
if ((ap->way & AUTH_HOW_MASK) == AUTH_HOW_MUTUAL)
{
if ((r = krb5_mk_rep (telnet_context, auth_context, &outbuf)))
{
snprintf (errbuf, errbuflen, "Make reply failed: %s",
error_message (r));
return 1;
}
Data (ap, KRB_RESPONSE, outbuf.data, outbuf.length);
}
if (krb5_unparse_name (telnet_context, ticket->enc_part2->client, &name))
name = 0;
Data (ap, KRB_ACCEPT, name, name ? -1 : 0);
DEBUG (("telnetd: Kerberos5 identifies him as ``%s''\r\n",
name ? name : ""));
auth_finished (ap, AUTH_USER);
free (name);
krb5_auth_con_getremotesubkey (telnet_context, auth_context, &newkey);
if (session_key)
{
krb5_free_keyblock (telnet_context, session_key);
session_key = 0;
}
if (newkey)
{
krb5_copy_keyblock (telnet_context, newkey, &session_key);
krb5_free_keyblock (telnet_context, newkey);
}
else
{
krb5_copy_keyblock (telnet_context, ticket->enc_part2->session,
&session_key);
}
telnet_encrypt_key (&skey);
return 0;
}
int
ksm_rgenerate_out_msg(struct snmp_secmod_outgoing_params *parms)
{
krb5_auth_context auth_context = NULL;
krb5_error_code retcode;
krb5_ccache cc = NULL;
int retval = SNMPERR_SUCCESS;
krb5_data outdata, ivector;
krb5_keyblock *subkey = NULL;
#ifdef MIT_NEW_CRYPTO
krb5_data input;
krb5_enc_data output;
unsigned int numcksumtypes;
krb5_cksumtype *cksumtype_array;
#else /* MIT_NEW_CRYPTO */
krb5_encrypt_block eblock;
#endif /* MIT_NEW_CRYPTO */
size_t blocksize, encrypted_length;
unsigned char *encrypted_data = NULL;
int zero = 0, i;
u_char *cksum_pointer, *endp = *parms->wholeMsg;
krb5_cksumtype cksumtype;
krb5_checksum pdu_checksum;
u_char **wholeMsg = parms->wholeMsg;
size_t *offset = parms->wholeMsgOffset, seq_offset;
struct ksm_secStateRef *ksm_state = (struct ksm_secStateRef *)
parms->secStateRef;
int rc;
DEBUGMSGTL(("ksm", "Starting KSM processing\n"));
outdata.length = 0;
outdata.data = NULL;
ivector.length = 0;
ivector.data = NULL;
pdu_checksum.contents = NULL;
if (!ksm_state) {
/*
* If we don't have a ksm_state, then we're a request. Get a
* credential cache and build a ap_req.
*/
retcode = krb5_cc_default(kcontext, &cc);
if (retcode) {
DEBUGMSGTL(("ksm", "KSM: krb5_cc_default failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
DEBUGMSGTL(("ksm", "KSM: Set credential cache successfully\n"));
/*
* This seems odd, since we don't need this until later (or earlier,
* depending on how you look at it), but because the most likely
* errors are Kerberos at this point, I'll get this now to save
* time not encoding the rest of the packet.
*
* Also, we need the subkey to encrypt the PDU (if required).
*/
retcode =
krb5_mk_req(kcontext, &auth_context,
AP_OPTS_MUTUAL_REQUIRED | AP_OPTS_USE_SUBKEY,
(char *) service_name, parms->session->peername, NULL,
cc, &outdata);
if (retcode) {
DEBUGMSGTL(("ksm", "KSM: krb5_mk_req failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
DEBUGMSGTL(("ksm", "KSM: ticket retrieved successfully for \"%s/%s\" "
"(may not be actual ticket sname)\n", service_name,
parms->session->peername));
} else {
/*
* Grab the auth_context from our security state reference
*/
auth_context = ksm_state->auth_context;
/*
* Bundle up an AP_REP. Note that we do this only when we
* have a security state reference (which means we're in an agent
* and we're sending a response).
*/
DEBUGMSGTL(("ksm", "KSM: Starting reply processing.\n"));
retcode = krb5_mk_rep(kcontext, auth_context, &outdata);
if (retcode) {
DEBUGMSGTL(("ksm", "KSM: krb5_mk_rep failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
DEBUGMSGTL(("ksm", "KSM: Finished with krb5_mk_rep()\n"));
}
/*
* If we have to encrypt the PDU, do that now
*/
if (parms->secLevel == SNMP_SEC_LEVEL_AUTHPRIV) {
DEBUGMSGTL(("ksm", "KSM: Starting PDU encryption.\n"));
/*
* It's weird -
*
* If we're on the manager, it's a local subkey (because that's in
* our AP_REQ)
*
* If we're on the agent, it's a remote subkey (because that comes
* FROM the received AP_REQ).
*/
if (ksm_state)
retcode = krb5_auth_con_getremotesubkey(kcontext, auth_context,
&subkey);
else
retcode = krb5_auth_con_getlocalsubkey(kcontext, auth_context,
&subkey);
if (retcode) {
DEBUGMSGTL(("ksm",
"KSM: krb5_auth_con_getlocalsubkey failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
/*
* Note that here we need to handle different things between the
* old and new crypto APIs. First, we need to get the final encrypted
* length of the PDU.
*/
#ifdef MIT_NEW_CRYPTO
retcode = krb5_c_encrypt_length(kcontext, subkey->enctype,
parms->scopedPduLen,
&encrypted_length);
if (retcode) {
DEBUGMSGTL(("ksm",
"Encryption length calculation failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
#else /* MIT_NEW_CRYPTO */
krb5_use_enctype(kcontext, &eblock, subkey->enctype);
retcode = krb5_process_key(kcontext, &eblock, subkey);
if (retcode) {
DEBUGMSGTL(("ksm", "krb5_process_key failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
encrypted_length = krb5_encrypt_size(parms->scopedPduLen,
eblock.crypto_entry);
#endif /* MIT_NEW_CRYPTO */
encrypted_data = malloc(encrypted_length);
if (!encrypted_data) {
DEBUGMSGTL(("ksm",
"KSM: Unable to malloc %d bytes for encrypt "
"buffer: %s\n", parms->scopedPduLen,
strerror(errno)));
retval = SNMPERR_MALLOC;
#ifndef MIT_NEW_CRYPTO
krb5_finish_key(kcontext, &eblock);
#endif /* ! MIT_NEW_CRYPTO */
goto error;
}
/*
* We need to set up a blank initialization vector for the encryption.
* Use a block of all zero's (which is dependent on the block size
* of the encryption method).
*/
#ifdef MIT_NEW_CRYPTO
retcode = krb5_c_block_size(kcontext, subkey->enctype, &blocksize);
if (retcode) {
DEBUGMSGTL(("ksm",
"Unable to determine crypto block size: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
#else /* MIT_NEW_CRYPTO */
blocksize =
krb5_enctype_array[subkey->enctype]->system->block_length;
#endif /* MIT_NEW_CRYPTO */
ivector.data = malloc(blocksize);
if (!ivector.data) {
DEBUGMSGTL(("ksm", "Unable to allocate %d bytes for ivector\n",
blocksize));
retval = SNMPERR_MALLOC;
goto error;
}
ivector.length = blocksize;
memset(ivector.data, 0, blocksize);
/*
* Finally! Do the encryption!
*/
#ifdef MIT_NEW_CRYPTO
input.data = (char *) parms->scopedPdu;
input.length = parms->scopedPduLen;
output.ciphertext.data = (char *) encrypted_data;
output.ciphertext.length = encrypted_length;
retcode =
krb5_c_encrypt(kcontext, subkey, KSM_KEY_USAGE_ENCRYPTION,
&ivector, &input, &output);
#else /* MIT_NEW_CRYPTO */
retcode = krb5_encrypt(kcontext, (krb5_pointer) parms->scopedPdu,
(krb5_pointer) encrypted_data,
parms->scopedPduLen, &eblock, ivector.data);
krb5_finish_key(kcontext, &eblock);
#endif /* MIT_NEW_CRYPTO */
if (retcode) {
DEBUGMSGTL(("ksm", "KSM: krb5_encrypt failed: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
snmp_set_detail(error_message(retcode));
goto error;
}
*offset = 0;
rc = asn_realloc_rbuild_string(wholeMsg, parms->wholeMsgLen,
offset, 1,
(u_char) (ASN_UNIVERSAL |
ASN_PRIMITIVE |
ASN_OCTET_STR),
encrypted_data,
encrypted_length);
if (rc == 0) {
DEBUGMSGTL(("ksm", "Building encrypted payload failed.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
DEBUGMSGTL(("ksm", "KSM: Encryption complete.\n"));
} else {
/*
* Plaintext PDU (not encrypted)
*/
if (*parms->wholeMsgLen < parms->scopedPduLen) {
DEBUGMSGTL(("ksm", "Not enough room for plaintext PDU.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
}
/*
* Start encoding the msgSecurityParameters
*
* For now, use 0 for the response hint
*/
DEBUGMSGTL(("ksm", "KSM: scopedPdu added to payload\n"));
seq_offset = *offset;
rc = asn_realloc_rbuild_int(wholeMsg, parms->wholeMsgLen,
offset, 1,
(u_char) (ASN_UNIVERSAL |
ASN_PRIMITIVE |
ASN_INTEGER),
(long *) &zero, sizeof(zero));
if (rc == 0) {
DEBUGMSGTL(("ksm", "Building ksm security parameters failed.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
rc = asn_realloc_rbuild_string(wholeMsg, parms->wholeMsgLen,
offset, 1,
(u_char) (ASN_UNIVERSAL |
ASN_PRIMITIVE |
ASN_OCTET_STR),
(u_char *) outdata.data,
outdata.length);
if (rc == 0) {
DEBUGMSGTL(("ksm", "Building ksm AP_REQ failed.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
/*
* Now, we need to pick the "right" checksum algorithm. For old
* crypto, just pick CKSUMTYPE_RSA_MD5_DES; for new crypto, pick
* one of the "approved" ones.
*/
#ifdef MIT_NEW_CRYPTO
retcode = krb5_c_keyed_checksum_types(kcontext, subkey->enctype,
&numcksumtypes, &cksumtype_array);
if (retcode) {
DEBUGMSGTL(("ksm", "Unable to find appropriate keyed checksum: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
if (numcksumtypes <= 0) {
DEBUGMSGTL(("ksm", "We received a list of zero cksumtypes for this "
"enctype (%d)\n", subkey->enctype));
snmp_set_detail("No valid checksum type for this encryption type");
retval = SNMPERR_KRB5;
goto error;
}
/*
* It's not clear to me from the API which checksum you're supposed
* to support, so I'm taking a guess at the first one
*/
cksumtype = cksumtype_array[0];
krb5_free_cksumtypes(kcontext, cksumtype_array);
DEBUGMSGTL(("ksm", "KSM: Choosing checksum type of %d (subkey type "
"of %d)\n", cksumtype, subkey->enctype));
retcode = krb5_c_checksum_length(kcontext, cksumtype, &blocksize);
if (retcode) {
DEBUGMSGTL(("ksm", "Unable to determine checksum length: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
pdu_checksum.length = blocksize;
#else /* MIT_NEW_CRYPTO */
if (ksm_state)
cksumtype = ksm_state->cksumtype;
else
cksumtype = CKSUMTYPE_RSA_MD5_DES;
if (!is_keyed_cksum(cksumtype)) {
DEBUGMSGTL(("ksm", "Checksum type %d is not a keyed checksum\n",
cksumtype));
snmp_set_detail("Checksum is not a keyed checksum");
retval = SNMPERR_KRB5;
goto error;
}
if (!is_coll_proof_cksum(cksumtype)) {
DEBUGMSGTL(("ksm", "Checksum type %d is not a collision-proof "
"checksum\n", cksumtype));
snmp_set_detail("Checksum is not a collision-proof checksum");
retval = SNMPERR_KRB5;
goto error;
}
pdu_checksum.length = krb5_checksum_size(kcontext, cksumtype);
pdu_checksum.checksum_type = cksumtype;
#endif /* MIT_NEW_CRYPTO */
/*
* Note that here, we're just leaving blank space for the checksum;
* we remember where that is, and we'll fill it in later.
*/
*offset += pdu_checksum.length;
memset(*wholeMsg + *parms->wholeMsgLen - *offset, 0, pdu_checksum.length);
cksum_pointer = *wholeMsg + *parms->wholeMsgLen - *offset;
rc = asn_realloc_rbuild_header(wholeMsg, parms->wholeMsgLen,
parms->wholeMsgOffset, 1,
(u_char) (ASN_UNIVERSAL |
ASN_PRIMITIVE |
ASN_OCTET_STR),
pdu_checksum.length);
if (rc == 0) {
DEBUGMSGTL(("ksm", "Building ksm security parameters failed.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
rc = asn_realloc_rbuild_int(wholeMsg, parms->wholeMsgLen,
parms->wholeMsgOffset, 1,
(u_char) (ASN_UNIVERSAL |
ASN_PRIMITIVE |
ASN_OCTET_STR),
(long *) &cksumtype,
sizeof(cksumtype));
if (rc == 0) {
DEBUGMSGTL(("ksm", "Building ksm security parameters failed.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
rc = asn_realloc_rbuild_sequence(wholeMsg, parms->wholeMsgLen,
parms->wholeMsgOffset, 1,
(u_char) (ASN_SEQUENCE |
ASN_CONSTRUCTOR),
*offset - seq_offset);
if (rc == 0) {
DEBUGMSGTL(("ksm", "Building ksm security parameters failed.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
rc = asn_realloc_rbuild_header(wholeMsg, parms->wholeMsgLen,
parms->wholeMsgOffset, 1,
(u_char) (ASN_UNIVERSAL |
ASN_PRIMITIVE |
ASN_OCTET_STR),
*offset - seq_offset);
if (rc == 0) {
DEBUGMSGTL(("ksm", "Building ksm security parameters failed.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
DEBUGMSGTL(("ksm", "KSM: Security parameter encoding completed\n"));
/*
* We're done with the KSM security parameters - now we do the global
* header and wrap up the whole PDU.
*/
if (*parms->wholeMsgLen < parms->globalDataLen) {
DEBUGMSGTL(("ksm", "Building global data failed.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
*offset += parms->globalDataLen;
memcpy(*wholeMsg + *parms->wholeMsgLen - *offset,
parms->globalData, parms->globalDataLen);
rc = asn_realloc_rbuild_sequence(wholeMsg, parms->wholeMsgLen,
offset, 1,
(u_char) (ASN_SEQUENCE |
ASN_CONSTRUCTOR),
*offset);
if (rc == 0) {
DEBUGMSGTL(("ksm", "Building master packet sequence.\n"));
retval = SNMPERR_TOO_LONG;
goto error;
}
DEBUGMSGTL(("ksm", "KSM: PDU master packet encoding complete.\n"));
/*
* Now we need to checksum the entire PDU (since it's built).
*/
pdu_checksum.contents = malloc(pdu_checksum.length);
if (!pdu_checksum.contents) {
DEBUGMSGTL(("ksm", "Unable to malloc %d bytes for checksum\n",
pdu_checksum.length));
retval = SNMPERR_MALLOC;
goto error;
}
/*
* If we didn't encrypt the packet, we haven't yet got the subkey.
* Get that now.
*/
if (!subkey) {
if (ksm_state)
retcode = krb5_auth_con_getremotesubkey(kcontext, auth_context,
&subkey);
else
retcode = krb5_auth_con_getlocalsubkey(kcontext, auth_context,
&subkey);
if (retcode) {
DEBUGMSGTL(("ksm", "krb5_auth_con_getlocalsubkey failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
}
#ifdef MIT_NEW_CRYPTO
input.data = (char *) (*wholeMsg + *parms->wholeMsgLen - *offset);
input.length = *offset;
retcode = krb5_c_make_checksum(kcontext, cksumtype, subkey,
KSM_KEY_USAGE_CHECKSUM, &input,
&pdu_checksum);
#else /* MIT_NEW_CRYPTO */
retcode = krb5_calculate_checksum(kcontext, cksumtype, *wholeMsg +
*parms->wholeMsgLen - *offset,
*offset,
(krb5_pointer) subkey->contents,
subkey->length, &pdu_checksum);
#endif /* MIT_NEW_CRYPTO */
if (retcode) {
DEBUGMSGTL(("ksm", "Calculate checksum failed: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
snmp_set_detail(error_message(retcode));
goto error;
}
DEBUGMSGTL(("ksm", "KSM: Checksum calculation complete.\n"));
memcpy(cksum_pointer, pdu_checksum.contents, pdu_checksum.length);
DEBUGMSGTL(("ksm", "KSM: Writing checksum of %d bytes at offset %d\n",
pdu_checksum.length, cksum_pointer - (*wholeMsg + 1)));
DEBUGMSGTL(("ksm", "KSM: Checksum:"));
for (i = 0; i < pdu_checksum.length; i++)
DEBUGMSG(("ksm", " %02x",
(unsigned int) pdu_checksum.contents[i]));
DEBUGMSG(("ksm", "\n"));
/*
* If we're _not_ called as part of a response (null ksm_state),
* then save the auth_context for later using our cache routines.
*/
if (!ksm_state) {
if ((retval = ksm_insert_cache(parms->pdu->msgid, auth_context,
(u_char *) parms->secName,
parms->secNameLen)) !=
SNMPERR_SUCCESS)
goto error;
auth_context = NULL;
}
DEBUGMSGTL(("ksm", "KSM processing complete!\n"));
error:
if (pdu_checksum.contents)
#ifdef MIT_NEW_CRYPTO
krb5_free_checksum_contents(kcontext, &pdu_checksum);
#else /* MIT_NEW_CRYPTO */
free(pdu_checksum.contents);
#endif /* MIT_NEW_CRYPTO */
if (ivector.data)
free(ivector.data);
if (subkey)
krb5_free_keyblock(kcontext, subkey);
if (encrypted_data)
free(encrypted_data);
if (cc)
krb5_cc_close(kcontext, cc);
if (auth_context && !ksm_state)
krb5_auth_con_free(kcontext, auth_context);
return retval;
}
int
ksm_process_in_msg(struct snmp_secmod_incoming_params *parms)
{
long temp;
krb5_cksumtype cksumtype;
krb5_auth_context auth_context = NULL;
krb5_error_code retcode;
krb5_checksum checksum;
krb5_data ap_req, ivector;
krb5_flags flags;
krb5_keyblock *subkey = NULL;
#ifdef MIT_NEW_CRYPTO
krb5_data input, output;
krb5_boolean valid;
krb5_enc_data in_crypt;
#else /* MIT_NEW_CRYPTO */
krb5_encrypt_block eblock;
#endif /* MIT_NEW_CRYPTO */
krb5_ticket *ticket = NULL;
int retval = SNMPERR_SUCCESS, response = 0;
size_t length =
parms->wholeMsgLen - (u_int) (parms->secParams - parms->wholeMsg);
u_char *current = parms->secParams, type;
size_t cksumlength, blocksize;
long hint;
char *cname;
struct ksm_secStateRef *ksm_state;
struct ksm_cache_entry *entry;
DEBUGMSGTL(("ksm", "Processing has begun\n"));
checksum.contents = NULL;
ap_req.data = NULL;
ivector.length = 0;
ivector.data = NULL;
/*
* First, parse the security parameters (because we need the subkey inside
* of the ticket to do anything
*/
if ((current = asn_parse_sequence(current, &length, &type,
(ASN_UNIVERSAL | ASN_PRIMITIVE |
ASN_OCTET_STR),
"ksm first octet")) == NULL) {
DEBUGMSGTL(("ksm", "Initial security paramter parsing failed\n"));
retval = SNMPERR_ASN_PARSE_ERR;
goto error;
}
if ((current = asn_parse_sequence(current, &length, &type,
(ASN_SEQUENCE | ASN_CONSTRUCTOR),
"ksm sequence")) == NULL) {
DEBUGMSGTL(("ksm",
"Security parameter sequence parsing failed\n"));
retval = SNMPERR_ASN_PARSE_ERR;
goto error;
}
if ((current = asn_parse_int(current, &length, &type, &temp,
sizeof(temp))) == NULL) {
DEBUGMSGTL(("ksm", "Security parameter checksum type parsing"
"failed\n"));
retval = SNMPERR_ASN_PARSE_ERR;
goto error;
}
cksumtype = temp;
#ifdef MIT_NEW_CRYPTO
if (!krb5_c_valid_cksumtype(cksumtype)) {
DEBUGMSGTL(("ksm", "Invalid checksum type (%d)\n", cksumtype));
retval = SNMPERR_KRB5;
snmp_set_detail("Invalid checksum type");
goto error;
}
if (!krb5_c_is_keyed_cksum(cksumtype)) {
DEBUGMSGTL(("ksm", "Checksum type %d is not a keyed checksum\n",
cksumtype));
snmp_set_detail("Checksum is not a keyed checksum");
retval = SNMPERR_KRB5;
goto error;
}
if (!krb5_c_is_coll_proof_cksum(cksumtype)) {
DEBUGMSGTL(("ksm", "Checksum type %d is not a collision-proof "
"checksum\n", cksumtype));
snmp_set_detail("Checksum is not a collision-proof checksum");
retval = SNMPERR_KRB5;
goto error;
}
#else /* ! MIT_NEW_CRYPTO */
if (!valid_cksumtype(cksumtype)) {
DEBUGMSGTL(("ksm", "Invalid checksum type (%d)\n", cksumtype));
retval = SNMPERR_KRB5;
snmp_set_detail("Invalid checksum type");
goto error;
}
if (!is_keyed_cksum(cksumtype)) {
DEBUGMSGTL(("ksm", "Checksum type %d is not a keyed checksum\n",
cksumtype));
snmp_set_detail("Checksum is not a keyed checksum");
retval = SNMPERR_KRB5;
goto error;
}
if (!is_coll_proof_cksum(cksumtype)) {
DEBUGMSGTL(("ksm", "Checksum type %d is not a collision-proof "
"checksum\n", cksumtype));
snmp_set_detail("Checksum is not a collision-proof checksum");
retval = SNMPERR_KRB5;
goto error;
}
#endif /* MIT_NEW_CRYPTO */
checksum.checksum_type = cksumtype;
cksumlength = length;
if ((current = asn_parse_sequence(current, &cksumlength, &type,
(ASN_UNIVERSAL | ASN_PRIMITIVE |
ASN_OCTET_STR), "ksm checksum")) ==
NULL) {
DEBUGMSGTL(("ksm",
"Security parameter checksum parsing failed\n"));
retval = SNMPERR_ASN_PARSE_ERR;
goto error;
}
checksum.contents = malloc(cksumlength);
if (!checksum.contents) {
DEBUGMSGTL(("ksm", "Unable to malloc %d bytes for checksum.\n",
cksumlength));
retval = SNMPERR_MALLOC;
goto error;
}
memcpy(checksum.contents, current, cksumlength);
checksum.length = cksumlength;
checksum.checksum_type = cksumtype;
/*
* Zero out the checksum so the validation works correctly
*/
memset(current, 0, cksumlength);
current += cksumlength;
length = parms->wholeMsgLen - (u_int) (current - parms->wholeMsg);
if ((current = asn_parse_sequence(current, &length, &type,
(ASN_UNIVERSAL | ASN_PRIMITIVE |
ASN_OCTET_STR), "ksm ap_req")) ==
NULL) {
DEBUGMSGTL(("ksm", "KSM security parameter AP_REQ/REP parsing "
"failed\n"));
retval = SNMPERR_ASN_PARSE_ERR;
goto error;
}
ap_req.length = length;
ap_req.data = malloc(length);
if (!ap_req.data) {
DEBUGMSGTL(("ksm",
"KSM unable to malloc %d bytes for AP_REQ/REP.\n",
length));
retval = SNMPERR_MALLOC;
goto error;
}
memcpy(ap_req.data, current, length);
current += length;
length = parms->wholeMsgLen - (u_int) (current - parms->wholeMsg);
if ((current = asn_parse_int(current, &length, &type, &hint,
sizeof(hint))) == NULL) {
DEBUGMSGTL(("ksm",
"KSM security parameter hint parsing failed\n"));
retval = SNMPERR_ASN_PARSE_ERR;
goto error;
}
/*
* Okay! We've got it all! Now try decoding the damn ticket.
*
* But of course there's a WRINKLE! We need to figure out if we're
* processing a AP_REQ or an AP_REP. How do we do that? We're going
* to cheat, and look at the first couple of bytes (which is what
* the Kerberos library routines do anyway).
*
* If there are ever new Kerberos message formats, we'll need to fix
* this here.
*
* If it's a _response_, then we need to get the auth_context
* from our cache.
*/
if (ap_req.length
&& (ap_req.data[0] == 0x6e || ap_req.data[0] == 0x4e)) {
/*
* We need to initalize the authorization context, and set the
* replay cache in it (and initialize the replay cache if we
* haven't already
*/
retcode = krb5_auth_con_init(kcontext, &auth_context);
if (retcode) {
DEBUGMSGTL(("ksm", "krb5_auth_con_init failed: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
snmp_set_detail(error_message(retcode));
goto error;
}
if (!rcache) {
krb5_data server;
server.data = "host";
server.length = strlen(server.data);
retcode = krb5_get_server_rcache(kcontext, &server, &rcache);
if (retcode) {
DEBUGMSGTL(("ksm", "krb5_get_server_rcache failed: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
snmp_set_detail(error_message(retcode));
goto error;
}
}
retcode = krb5_auth_con_setrcache(kcontext, auth_context, rcache);
if (retcode) {
DEBUGMSGTL(("ksm", "krb5_auth_con_setrcache failed: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
snmp_set_detail(error_message(retcode));
goto error;
}
retcode = krb5_rd_req(kcontext, &auth_context, &ap_req, NULL,
keytab, &flags, &ticket);
krb5_auth_con_setrcache(kcontext, auth_context, NULL);
if (retcode) {
DEBUGMSGTL(("ksm", "krb5_rd_req() failed: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
snmp_set_detail(error_message(retcode));
goto error;
}
retcode =
krb5_unparse_name(kcontext, ticket->enc_part2->client, &cname);
if (retcode == 0) {
DEBUGMSGTL(("ksm", "KSM authenticated principal name: %s\n",
cname));
free(cname);
}
/*
* Check to make sure AP_OPTS_MUTUAL_REQUIRED was set
*/
if (!(flags & AP_OPTS_MUTUAL_REQUIRED)) {
DEBUGMSGTL(("ksm",
"KSM MUTUAL_REQUIRED not set in request!\n"));
retval = SNMPERR_KRB5;
snmp_set_detail("MUTUAL_REQUIRED not set in message");
goto error;
}
retcode =
krb5_auth_con_getremotesubkey(kcontext, auth_context, &subkey);
if (retcode) {
DEBUGMSGTL(("ksm", "KSM remote subkey retrieval failed: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
snmp_set_detail(error_message(retcode));
goto error;
}
} else if (ap_req.length && (ap_req.data[0] == 0x6f ||
ap_req.data[0] == 0x4f)) {
/*
* Looks like a response; let's see if we've got that auth_context
* in our cache.
*/
krb5_ap_rep_enc_part *repl = NULL;
response = 1;
entry = ksm_get_cache(parms->pdu->msgid);
if (!entry) {
DEBUGMSGTL(("ksm",
"KSM: Unable to find auth_context for PDU with "
"message ID of %ld\n", parms->pdu->msgid));
retval = SNMPERR_KRB5;
goto error;
}
auth_context = entry->auth_context;
/*
* In that case, let's call the rd_rep function
*/
retcode = krb5_rd_rep(kcontext, auth_context, &ap_req, &repl);
if (repl)
krb5_free_ap_rep_enc_part(kcontext, repl);
if (retcode) {
DEBUGMSGTL(("ksm", "KSM: krb5_rd_rep() failed: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
goto error;
}
DEBUGMSGTL(("ksm", "KSM: krb5_rd_rep() decoded successfully.\n"));
retcode =
krb5_auth_con_getlocalsubkey(kcontext, auth_context, &subkey);
if (retcode) {
DEBUGMSGTL(("ksm", "Unable to retrieve local subkey: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
snmp_set_detail("Unable to retrieve local subkey");
goto error;
}
} else {
DEBUGMSGTL(("ksm", "Unknown Kerberos message type (%02x)\n",
ap_req.data[0]));
retval = SNMPERR_KRB5;
snmp_set_detail("Unknown Kerberos message type");
goto error;
}
#ifdef MIT_NEW_CRYPTO
input.data = (char *) parms->wholeMsg;
input.length = parms->wholeMsgLen;
retcode =
krb5_c_verify_checksum(kcontext, subkey, KSM_KEY_USAGE_CHECKSUM,
&input, &checksum, &valid);
#else /* MIT_NEW_CRYPTO */
retcode = krb5_verify_checksum(kcontext, cksumtype, &checksum,
parms->wholeMsg, parms->wholeMsgLen,
(krb5_pointer) subkey->contents,
subkey->length);
#endif /* MIT_NEW_CRYPTO */
if (retcode) {
DEBUGMSGTL(("ksm", "KSM checksum verification failed: %s\n",
error_message(retcode)));
retval = SNMPERR_KRB5;
snmp_set_detail(error_message(retcode));
goto error;
}
/*
* Don't ask me why they didn't simply return an error, but we have
* to check to see if "valid" is false.
*/
#ifdef MIT_NEW_CRYPTO
if (!valid) {
DEBUGMSGTL(("ksm", "Computed checksum did not match supplied "
"checksum!\n"));
retval = SNMPERR_KRB5;
snmp_set_detail
("Computed checksum did not match supplied checksum");
goto error;
}
#endif /* MIT_NEW_CRYPTO */
/*
* Handle an encrypted PDU. Note that it's an OCTET_STRING of the
* output of whatever Kerberos cryptosystem you're using (defined by
* the encryption type). Note that this is NOT the EncryptedData
* sequence - it's what goes in the "cipher" field of EncryptedData.
*/
if (parms->secLevel == SNMP_SEC_LEVEL_AUTHPRIV) {
if ((current = asn_parse_sequence(current, &length, &type,
(ASN_UNIVERSAL | ASN_PRIMITIVE |
ASN_OCTET_STR), "ksm pdu")) ==
NULL) {
DEBUGMSGTL(("ksm", "KSM sPDU octet decoding failed\n"));
retval = SNMPERR_ASN_PARSE_ERR;
goto error;
}
/*
* The PDU is now pointed at by "current", and the length is in
* "length".
*/
DEBUGMSGTL(("ksm", "KSM starting sPDU decode\n"));
/*
* We need to set up a blank initialization vector for the decryption.
* Use a block of all zero's (which is dependent on the block size
* of the encryption method).
*/
#ifdef MIT_NEW_CRYPTO
retcode = krb5_c_block_size(kcontext, subkey->enctype, &blocksize);
if (retcode) {
DEBUGMSGTL(("ksm",
"Unable to determine crypto block size: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
#else /* MIT_NEW_CRYPTO */
blocksize =
krb5_enctype_array[subkey->enctype]->system->block_length;
#endif /* MIT_NEW_CRYPTO */
ivector.data = malloc(blocksize);
if (!ivector.data) {
DEBUGMSGTL(("ksm", "Unable to allocate %d bytes for ivector\n",
blocksize));
retval = SNMPERR_MALLOC;
goto error;
}
ivector.length = blocksize;
memset(ivector.data, 0, blocksize);
#ifndef MIT_NEW_CRYPTO
krb5_use_enctype(kcontext, &eblock, subkey->enctype);
retcode = krb5_process_key(kcontext, &eblock, subkey);
if (retcode) {
DEBUGMSGTL(("ksm", "KSM key post-processing failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
#endif /* !MIT_NEW_CRYPTO */
if (length > *parms->scopedPduLen) {
DEBUGMSGTL(("ksm", "KSM not enough room - have %d bytes to "
"decrypt but only %d bytes available\n", length,
*parms->scopedPduLen));
retval = SNMPERR_TOO_LONG;
#ifndef MIT_NEW_CRYPTO
krb5_finish_key(kcontext, &eblock);
#endif /* ! MIT_NEW_CRYPTO */
goto error;
}
#ifdef MIT_NEW_CRYPTO
in_crypt.ciphertext.data = (char *) current;
in_crypt.ciphertext.length = length;
in_crypt.enctype = subkey->enctype;
output.data = (char *) *parms->scopedPdu;
output.length = *parms->scopedPduLen;
retcode =
krb5_c_decrypt(kcontext, subkey, KSM_KEY_USAGE_ENCRYPTION,
&ivector, &in_crypt, &output);
#else /* MIT_NEW_CRYPTO */
retcode = krb5_decrypt(kcontext, (krb5_pointer) current,
*parms->scopedPdu, length, &eblock,
ivector.data);
krb5_finish_key(kcontext, &eblock);
#endif /* MIT_NEW_CRYPTO */
if (retcode) {
DEBUGMSGTL(("ksm", "Decryption failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
*parms->scopedPduLen = length;
} else {
/*
* Clear PDU
*/
*parms->scopedPdu = current;
*parms->scopedPduLen =
parms->wholeMsgLen - (current - parms->wholeMsg);
}
/*
* A HUGE GROSS HACK
*/
*parms->maxSizeResponse = parms->maxMsgSize - 200;
DEBUGMSGTL(("ksm", "KSM processing complete\n"));
/*
* Set the secName to the right value (a hack for now). But that's
* only used for when we're processing a request, not a response.
*/
if (!response) {
retcode = krb5_unparse_name(kcontext, ticket->enc_part2->client,
&cname);
if (retcode) {
DEBUGMSGTL(("ksm", "KSM krb5_unparse_name failed: %s\n",
error_message(retcode)));
snmp_set_detail(error_message(retcode));
retval = SNMPERR_KRB5;
goto error;
}
if (strlen(cname) > *parms->secNameLen + 1) {
DEBUGMSGTL(("ksm",
"KSM: Principal length (%d) is too long (%d)\n",
strlen(cname), parms->secNameLen));
retval = SNMPERR_TOO_LONG;
free(cname);
goto error;
}
strcpy(parms->secName, cname);
*parms->secNameLen = strlen(cname);
free(cname);
/*
* Also, if we're not a response, keep around our auth_context so we
* can encode the reply message correctly
*/
ksm_state = SNMP_MALLOC_STRUCT(ksm_secStateRef);
if (!ksm_state) {
DEBUGMSGTL(("ksm", "KSM unable to malloc memory for "
"ksm_secStateRef\n"));
retval = SNMPERR_MALLOC;
goto error;
}
ksm_state->auth_context = auth_context;
auth_context = NULL;
ksm_state->cksumtype = cksumtype;
*parms->secStateRef = ksm_state;
} else {
/*
* We _still_ have to set the secName in process_in_msg(). Do
* that now with what we were passed in before (we cached it,
* remember?)
*/
memcpy(parms->secName, entry->secName, entry->secNameLen);
*parms->secNameLen = entry->secNameLen;
}
/*
* Just in case
*/
parms->secEngineID = (u_char *) "";
*parms->secEngineIDLen = 0;
auth_context = NULL; /* So we don't try to free it on success */
error:
if (retval == SNMPERR_ASN_PARSE_ERR &&
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS) == 0)
DEBUGMSGTL(("ksm", "Failed to increment statistics.\n"));
if (subkey)
krb5_free_keyblock(kcontext, subkey);
if (checksum.contents)
free(checksum.contents);
if (ivector.data)
free(ivector.data);
if (ticket)
krb5_free_ticket(kcontext, ticket);
if (!response && auth_context)
krb5_auth_con_free(kcontext, auth_context);
if (ap_req.data)
free(ap_req.data);
return retval;
}
