/*
* Naming extensions based local login authorization.
*/
static OM_uint32
attr_authorize_localname(OM_uint32 *minor,
const gss_name_t name,
const gss_union_name_t unionUser)
{
OM_uint32 major = GSS_S_UNAVAILABLE; /* attribute not present */
gss_buffer_t externalName;
int more = -1;
if (unionUser->name_type != GSS_C_NO_OID &&
!g_OID_equal(unionUser->name_type, GSS_C_NT_USER_NAME))
return (GSS_S_BAD_NAMETYPE);
externalName = unionUser->external_name;
assert(externalName != GSS_C_NO_BUFFER);
while (more != 0 && major != GSS_S_COMPLETE) {
OM_uint32 tmpMajor, tmpMinor;
gss_buffer_desc value;
gss_buffer_desc display_value;
int authenticated = 0, complete = 0;
tmpMajor = gss_get_name_attribute(minor,
name,
GSS_C_ATTR_LOCAL_LOGIN_USER,
&authenticated,
&complete,
&value,
&display_value,
&more);
if (GSS_ERROR(tmpMajor)) {
major = tmpMajor;
break;
}
if (authenticated &&
value.length == externalName->length &&
memcmp(value.value, externalName->value, externalName->length) == 0)
major = GSS_S_COMPLETE;
else
major = GSS_S_UNAUTHORIZED;
gss_release_buffer(&tmpMinor, &value);
gss_release_buffer(&tmpMinor, &display_value);
}
return (major);
}
OM_uint32
ntlm_gss_get_name_attribute(OM_uint32 *minor_status,
gss_name_t name,
gss_buffer_t attr,
int *authenticated,
int *complete,
gss_buffer_t value,
gss_buffer_t display_value,
int *more)
{
OM_uint32 ret;
ret = gss_get_name_attribute(minor_status,
name,
attr,
authenticated,
complete,
value,
display_value,
more);
return (ret);
}
static void
dump_attribute(gss_name_t name, gss_buffer_t attribute, int noisy)
{
OM_uint32 major, minor;
gss_buffer_desc value;
gss_buffer_desc display_value;
int authenticated = 0;
int complete = 0;
int more = -1;
unsigned int i;
while (more != 0) {
value.value = NULL;
display_value.value = NULL;
major = gss_get_name_attribute(&minor, name, attribute, &authenticated,
&complete, &value, &display_value,
&more);
check_gsserr("gss_get_name_attribute", major, minor);
printf("Attribute %.*s %s %s\n\n%.*s\n",
(int)attribute->length, (char *)attribute->value,
authenticated ? "Authenticated" : "",
complete ? "Complete" : "",
(int)display_value.length, (char *)display_value.value);
if (noisy) {
for (i = 0; i < value.length; i++) {
if ((i % 32) == 0)
printf("\n");
printf("%02x", ((char *)value.value)[i] & 0xFF);
}
printf("\n\n");
}
(void)gss_release_buffer(&minor, &value);
(void)gss_release_buffer(&minor, &display_value);
}
}
enum auth_stat
_svcauth_gss(struct svc_req *req, struct rpc_msg *msg,
bool *no_dispatch)
{
XDR xdrs[1];
SVCAUTH *auth;
struct svc_rpc_gss_data *gd = NULL;
struct rpc_gss_cred *gc = NULL;
struct rpc_gss_init_res gr;
int call_stat, offset;
OM_uint32 min_stat;
bool gd_locked = false;
bool gd_hashed = false;
/* Initialize reply. */
req->rq_verf = _null_auth;
/* Unserialize client credentials. */
if (req->rq_cred.oa_length <= 0)
svcauth_gss_return(AUTH_BADCRED);
gc = (struct rpc_gss_cred *)req->rq_clntcred;
memset(gc, 0, sizeof(struct rpc_gss_cred));
xdrmem_create(xdrs, req->rq_cred.oa_base, req->rq_cred.oa_length,
XDR_DECODE);
if (!xdr_rpc_gss_cred(xdrs, gc)) {
XDR_DESTROY(xdrs);
svcauth_gss_return(AUTH_BADCRED);
}
XDR_DESTROY(xdrs);
/* Check version. */
if (gc->gc_v != RPCSEC_GSS_VERSION)
svcauth_gss_return(AUTH_BADCRED);
if (gc->gc_seq > RPCSEC_GSS_MAXSEQ)
svcauth_gss_return(RPCSEC_GSS_CTXPROBLEM);
if (gc->gc_proc > RPCSEC_GSS_MAXPROC)
svcauth_gss_return(AUTH_BADCRED);
/* Check RPCSEC_GSS service. */
if (gc->gc_svc != RPCSEC_GSS_SVC_NONE
&& gc->gc_svc != RPCSEC_GSS_SVC_INTEGRITY
&& gc->gc_svc != RPCSEC_GSS_SVC_PRIVACY)
svcauth_gss_return(AUTH_BADCRED);
/* Context lookup. */
if ((gc->gc_proc == RPCSEC_GSS_DATA)
|| (gc->gc_proc == RPCSEC_GSS_DESTROY)) {
/* Per RFC 2203 5.3.3.3, if a valid security context
* cannot be found to authorize a request, the
* implementation returns RPCSEC_GSS_CREDPROBLEM.
* N.B., we are explicitly allowed to discard contexts
* for any reason (e.g., to save space). */
gd = authgss_ctx_hash_get(gc);
if (!gd)
svcauth_gss_return(RPCSEC_GSS_CREDPROBLEM);
gd_hashed = true;
if (gc->gc_svc != gd->sec.svc)
gd->sec.svc = gc->gc_svc;
}
if (!gd) {
/* Allocate and set up server auth handle. */
auth = mem_alloc(sizeof(SVCAUTH));
gd = alloc_svc_rpc_gss_data();
auth->svc_ah_ops = &svc_auth_gss_ops;
auth->svc_ah_private = (caddr_t) gd;
gd->auth = auth;
}
/* Serialize context. */
mutex_lock(&gd->lock);
gd_locked = true;
/* thread auth */
req->rq_auth = gd->auth;
/* Check sequence number. */
if (gd->established) {
if (get_time_fast() >= gd->endtime) {
*no_dispatch = true;
svcauth_gss_return(RPCSEC_GSS_CREDPROBLEM);
}
/* XXX implied serialization? or just fudging? advance if
* greater? */
offset = gd->seqlast - gc->gc_seq;
if (offset < 0) {
gd->seqlast = gc->gc_seq;
offset = 0 - offset;
gd->seqmask <<= offset;
offset = 0;
} else if (offset >= gd->win || (gd->seqmask & (1 << offset))) {
*no_dispatch = true;
svcauth_gss_return(AUTH_OK);
}
gd->seqmask |= (1 << offset); /* XXX harmless */
req->rq_ap1 = (void *)(uintptr_t) gc->gc_seq; /* GCC casts */
req->rq_clntname = (char *) gd->client_name;
req->rq_svcname = (char *) gd->ctx;
}
/* gd->established */
/* Handle RPCSEC_GSS control procedure. */
switch (gc->gc_proc) {
case RPCSEC_GSS_INIT:
case RPCSEC_GSS_CONTINUE_INIT:
if (req->rq_proc != NULLPROC)
svcauth_gss_return(AUTH_FAILED); /* XXX ? */
/* XXX why unconditionally acquire creds? */
if (!svcauth_gss_acquire_cred())
svcauth_gss_return(AUTH_FAILED);
if (!svcauth_gss_accept_sec_context(req, gd, &gr))
svcauth_gss_return(AUTH_REJECTEDCRED);
if (!svcauth_gss_nextverf(req, gd, htonl(gr.gr_win))) {
/* XXX check */
gss_release_buffer(&min_stat, &gr.gr_token);
mem_free(gr.gr_ctx.value, 0);
svcauth_gss_return(AUTH_FAILED);
}
*no_dispatch = true;
call_stat =
svc_sendreply(req->rq_xprt, req,
(xdrproc_t) xdr_rpc_gss_init_res,
(caddr_t) &gr);
/* XXX */
gss_release_buffer(&min_stat, &gr.gr_token);
gss_release_buffer(&min_stat, &gd->checksum);
mem_free(gr.gr_ctx.value, 0);
if (!call_stat)
svcauth_gss_return(AUTH_FAILED);
if (gr.gr_major == GSS_S_COMPLETE) {
gd->established = true;
if (!gd_hashed) {
/* krb5 pac -- try all that apply */
gss_buffer_desc attr, display_buffer;
/* completely generic */
int auth = 1, comp = 0, more = -1;
memset(&gd->pac.ms_pac, 0,
sizeof(gss_buffer_desc));
memset(&display_buffer, 0,
sizeof(gss_buffer_desc));
/* MS AD */
attr.value = "urn:mspac:";
attr.length = 10;
gr.gr_major =
gss_get_name_attribute(&gr.gr_minor,
gd->client_name,
&attr, &auth, &comp,
&gd->pac.ms_pac,
&display_buffer,
&more);
if (gr.gr_major == GSS_S_COMPLETE) {
/* dont need it */
gss_release_buffer(&gr.gr_minor,
&display_buffer);
gd->flags |= SVC_RPC_GSS_FLAG_MSPAC;
}
(void)authgss_ctx_hash_set(gd);
}
}
break;
/* XXX next 2 cases: is it correct to leave gd in cache
* after a validate or verf failure ? */
case RPCSEC_GSS_DATA:
call_stat = svcauth_gss_validate(req, gd, msg);
switch (call_stat) {
default:
svcauth_gss_return(RPCSEC_GSS_CREDPROBLEM);
case 0:
break;
}
if (!svcauth_gss_nextverf(req, gd, htonl(gc->gc_seq)))
svcauth_gss_return(AUTH_FAILED);
break;
case RPCSEC_GSS_DESTROY:
if (req->rq_proc != NULLPROC)
svcauth_gss_return(AUTH_FAILED); /* XXX ? */
if (svcauth_gss_validate(req, gd, msg))
svcauth_gss_return(RPCSEC_GSS_CREDPROBLEM);
if (!svcauth_gss_nextverf(req, gd, htonl(gc->gc_seq)))
svcauth_gss_return(AUTH_FAILED);
*no_dispatch = true;
(void)authgss_ctx_hash_del(gd);
/* avoid lock order reversal gd->lock, xprt->xp_lock */
mutex_unlock(&gd->lock);
gd_locked = false;
call_stat =
svc_sendreply(req->rq_xprt, req, (xdrproc_t) xdr_void,
(caddr_t) NULL);
/* We acquired a reference on gd with authgss_ctx_hash_get
* call. Time to release the reference as we don't need
* gd anymore.
*/
unref_svc_rpc_gss_data(gd, SVC_RPC_GSS_FLAG_NONE);
req->rq_auth = &svc_auth_none;
break;
default:
svcauth_gss_return(AUTH_REJECTEDCRED);
break;
}
svcauth_gss_return(AUTH_OK);
}
static int
gssattr_dynacl_mask(
void *priv,
Operation *op,
Entry *target,
AttributeDescription *desc,
struct berval *val,
int nmatch,
regmatch_t *matches,
slap_access_t *grant,
slap_access_t *deny )
{
gssattr_t *gssattr = (gssattr_t *)priv;
sasl_conn_t *sasl_ctx = op->o_conn->c_sasl_authctx;
gss_name_t gss_name = GSS_C_NO_NAME;
OM_uint32 major, minor;
int more = -1;
int authenticated, complete;
gss_buffer_desc attr = GSS_C_EMPTY_BUFFER;
int granted = 0;
ACL_INVALIDATE( *deny );
if ( sasl_ctx == NULL ||
sasl_getprop( sasl_ctx, SASL_GSS_PEER_NAME, (const void **)&gss_name) != 0 ||
gss_name == GSS_C_NO_NAME ) {
return 0;
}
attr.length = gssattr->gssattr_name.bv_len;
attr.value = gssattr->gssattr_name.bv_val;
while ( more != 0 ) {
AclRegexMatches amatches = { 0 };
gss_buffer_desc gss_value = GSS_C_EMPTY_BUFFER;
gss_buffer_desc gss_display_value = GSS_C_EMPTY_BUFFER;
struct berval bv_value;
major = gss_get_name_attribute( &minor, gss_name, &attr,
&authenticated, &complete,
&gss_value, &gss_display_value, &more );
if ( GSS_ERROR( major ) ) {
break;
} else if ( authenticated == 0 ) {
gss_release_buffer( &minor, &gss_value );
gss_release_buffer( &minor, &gss_display_value );
continue;
}
bv_value.bv_len = gss_value.length;
bv_value.bv_val = (char *)gss_value.value;
if ( !ber_bvccmp( &gssattr->gssattr_value, '*' ) ) {
if ( gssattr->gssattr_style != ACL_STYLE_BASE ) {
amatches.dn_count = nmatch;
AC_MEMCPY( amatches.dn_data, matches, sizeof( amatches.dn_data ) );
}
switch ( gssattr->gssattr_style ) {
case ACL_STYLE_REGEX:
/* XXX assumes value NUL terminated */
granted = regex_matches( &gssattr->gssattr_value, bv_value.bv_val,
&target->e_nname, val, &amatches );
break;
case ACL_STYLE_EXPAND: {
struct berval bv;
char buf[ACL_BUF_SIZE];
bv.bv_len = sizeof( buf ) - 1;
bv.bv_val = buf;
granted = ( acl_string_expand( &bv, &gssattr->gssattr_value,
&target->e_nname, val,
&amatches ) == 0 ) &&
( ber_bvstrcmp( &bv, &bv_value) == 0 );
break;
}
case ACL_STYLE_BASE:
granted = ( ber_bvstrcmp( &gssattr->gssattr_value, &bv_value ) == 0 );
break;
default:
assert(0);
break;
}
} else {
granted = 1;
}
gss_release_buffer( &minor, &gss_value );
gss_release_buffer( &minor, &gss_display_value );
if ( granted ) {
break;
}
}
if ( granted ) {
ACL_LVL_ASSIGN_WRITE( *grant );
}
return 0;
}
NTSTATUS gssapi_obtain_pac_blob(TALLOC_CTX *mem_ctx,
gss_ctx_id_t gssapi_context,
gss_name_t gss_client_name,
DATA_BLOB *pac_blob)
{
NTSTATUS status;
OM_uint32 gss_maj, gss_min;
#ifdef HAVE_GSS_GET_NAME_ATTRIBUTE
/*
* gss_get_name_attribute() in MIT krb5 1.10.0 can return unintialized pac_display_buffer
* and later gss_release_buffer() will crash on attempting to release it.
*
* So always initialize the buffer descriptors.
*
* See following links for more details:
* http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=658514
* http://krbdev.mit.edu/rt/Ticket/Display.html?user=guest&pass=guest&id=7087
*/
gss_buffer_desc pac_buffer = {
.value = NULL,
.length = 0
};
gss_buffer_desc pac_display_buffer = {
.value = NULL,
.length = 0
};
gss_buffer_desc pac_name = {
.value = discard_const("urn:mspac:"),
.length = sizeof("urn:mspac:")-1
};
int more = -1;
int authenticated = false;
int complete = false;
gss_maj = gss_get_name_attribute(
&gss_min, gss_client_name, &pac_name,
&authenticated, &complete,
&pac_buffer, &pac_display_buffer, &more);
if (gss_maj != 0) {
gss_OID oid = discard_const(gss_mech_krb5);
DBG_NOTICE("obtaining PAC via GSSAPI gss_get_name_attribute "
"failed: %s\n", gssapi_error_string(mem_ctx,
gss_maj, gss_min,
oid));
return NT_STATUS_ACCESS_DENIED;
} else if (authenticated && complete) {
/* The PAC blob is returned directly */
*pac_blob = data_blob_talloc(mem_ctx, pac_buffer.value,
pac_buffer.length);
if (!pac_blob->data) {
status = NT_STATUS_NO_MEMORY;
} else {
status = NT_STATUS_OK;
}
gss_maj = gss_release_buffer(&gss_min, &pac_buffer);
gss_maj = gss_release_buffer(&gss_min, &pac_display_buffer);
return status;
} else {
DEBUG(0, ("obtaining PAC via GSSAPI failed: authenticated: %s, complete: %s, more: %s\n",
authenticated ? "true" : "false",
complete ? "true" : "false",
more ? "true" : "false"));
return NT_STATUS_ACCESS_DENIED;
}
#elif defined(HAVE_GSS_INQUIRE_SEC_CONTEXT_BY_OID)
gss_OID_desc pac_data_oid = {
.elements = discard_const(EXTRACT_PAC_AUTHZ_DATA_FROM_SEC_CONTEXT_OID),
.length = EXTRACT_PAC_AUTHZ_DATA_FROM_SEC_CONTEXT_OID_LENGTH
};
gss_buffer_set_t set = GSS_C_NO_BUFFER_SET;
/* If we didn't have the routine to get a verified, validated
* PAC (supplied only by MIT at the time of writing), then try
* with the Heimdal OID (fetches the PAC directly and always
* validates) */
gss_maj = gss_inquire_sec_context_by_oid(
&gss_min, gssapi_context,
&pac_data_oid, &set);
/* First check for the error MIT gives for an unknown OID */
if (gss_maj == GSS_S_UNAVAILABLE) {
DEBUG(1, ("unable to obtain a PAC against this GSSAPI library. "
"GSSAPI secured connections are available only with Heimdal or MIT Kerberos >= 1.8\n"));
} else if (gss_maj != 0) {
DEBUG(2, ("obtaining PAC via GSSAPI gss_inqiure_sec_context_by_oid (Heimdal OID) failed: %s\n",
gssapi_error_string(mem_ctx, gss_maj, gss_min, gss_mech_krb5)));
} else {
if (set == GSS_C_NO_BUFFER_SET) {
DEBUG(0, ("gss_inquire_sec_context_by_oid returned unknown "
"data in results.\n"));
return NT_STATUS_INTERNAL_ERROR;
}
/* The PAC blob is returned directly */
*pac_blob = data_blob_talloc(mem_ctx, set->elements[0].value,
set->elements[0].length);
if (!pac_blob->data) {
status = NT_STATUS_NO_MEMORY;
} else {
status = NT_STATUS_OK;
}
gss_maj = gss_release_buffer_set(&gss_min, &set);
return status;
}
#else
DEBUG(1, ("unable to obtain a PAC against this GSSAPI library. "
"GSSAPI secured connections are available only with Heimdal or MIT Kerberos >= 1.8\n"));
#endif
return NT_STATUS_ACCESS_DENIED;
}
NTSTATUS gssapi_get_session_key(TALLOC_CTX *mem_ctx,
gss_ctx_id_t gssapi_context,
DATA_BLOB *session_key,
uint32_t *keytype)
{
OM_uint32 gss_min, gss_maj;
gss_buffer_set_t set = GSS_C_NO_BUFFER_SET;
gss_maj = gss_inquire_sec_context_by_oid(
&gss_min, gssapi_context,
&gse_sesskey_inq_oid, &set);
if (gss_maj) {
DEBUG(0, ("gss_inquire_sec_context_by_oid failed [%s]\n",
gssapi_error_string(mem_ctx,
gss_maj,
gss_min,
discard_const_p(struct gss_OID_desc_struct,
gss_mech_krb5))));
return NT_STATUS_NO_USER_SESSION_KEY;
}
if ((set == GSS_C_NO_BUFFER_SET) ||
(set->count == 0)) {
#ifdef HAVE_GSSKRB5_GET_SUBKEY
krb5_keyblock *subkey;
gss_maj = gsskrb5_get_subkey(&gss_min,
gssapi_context,
&subkey);
if (gss_maj != 0) {
DEBUG(1, ("NO session key for this mech\n"));
return NT_STATUS_NO_USER_SESSION_KEY;
}
if (session_key) {
*session_key = data_blob_talloc(mem_ctx,
KRB5_KEY_DATA(subkey), KRB5_KEY_LENGTH(subkey));
}
if (keytype) {
*keytype = KRB5_KEY_TYPE(subkey);
}
krb5_free_keyblock(NULL /* should be krb5_context */, subkey);
return NT_STATUS_OK;
#else
DEBUG(0, ("gss_inquire_sec_context_by_oid didn't return any session key (and no alternative method available)\n"));
return NT_STATUS_NO_USER_SESSION_KEY;
#endif
}
if (session_key) {
*session_key = data_blob_talloc(mem_ctx, set->elements[0].value,
set->elements[0].length);
}
if (keytype) {
int diflen, i;
const uint8_t *p;
*keytype = 0;
if (set->count < 2) {
#ifdef HAVE_GSSKRB5_GET_SUBKEY
krb5_keyblock *subkey;
gss_maj = gsskrb5_get_subkey(&gss_min,
gssapi_context,
&subkey);
if (gss_maj == 0) {
*keytype = KRB5_KEY_TYPE(subkey);
krb5_free_keyblock(NULL /* should be krb5_context */, subkey);
}
#endif
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_OK;
} else if (memcmp(set->elements[1].value,
gse_sesskeytype_oid.elements,
gse_sesskeytype_oid.length) != 0) {
/* Perhaps a non-krb5 session key */
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_OK;
}
p = (const uint8_t *)set->elements[1].value + gse_sesskeytype_oid.length;
diflen = set->elements[1].length - gse_sesskeytype_oid.length;
if (diflen <= 0) {
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_INVALID_PARAMETER;
}
for (i = 0; i < diflen; i++) {
*keytype = (*keytype << 7) | (p[i] & 0x7f);
if (i + 1 != diflen && (p[i] & 0x80) == 0) {
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_INVALID_PARAMETER;
}
}
}
gss_maj = gss_release_buffer_set(&gss_min, &set);
return NT_STATUS_OK;
}
char *gssapi_error_string(TALLOC_CTX *mem_ctx,
OM_uint32 maj_stat, OM_uint32 min_stat,
const gss_OID mech)
{
OM_uint32 disp_min_stat, disp_maj_stat;
gss_buffer_desc maj_error_message;
gss_buffer_desc min_error_message;
char *maj_error_string, *min_error_string;
OM_uint32 msg_ctx = 0;
char *ret;
maj_error_message.value = NULL;
min_error_message.value = NULL;
maj_error_message.length = 0;
min_error_message.length = 0;
disp_maj_stat = gss_display_status(&disp_min_stat, maj_stat,
GSS_C_GSS_CODE, mech,
&msg_ctx, &maj_error_message);
if (disp_maj_stat != 0) {
maj_error_message.value = NULL;
maj_error_message.length = 0;
}
disp_maj_stat = gss_display_status(&disp_min_stat, min_stat,
GSS_C_MECH_CODE, mech,
&msg_ctx, &min_error_message);
if (disp_maj_stat != 0) {
min_error_message.value = NULL;
min_error_message.length = 0;
}
maj_error_string = talloc_strndup(mem_ctx,
(char *)maj_error_message.value,
maj_error_message.length);
min_error_string = talloc_strndup(mem_ctx,
(char *)min_error_message.value,
min_error_message.length);
ret = talloc_asprintf(mem_ctx, "%s: %s",
maj_error_string, min_error_string);
talloc_free(maj_error_string);
talloc_free(min_error_string);
gss_release_buffer(&disp_min_stat, &maj_error_message);
gss_release_buffer(&disp_min_stat, &min_error_message);
return ret;
}
