r24833: Move locator to nsswitch (does not belong to libads anymore).

Guenther
(This used to be commit af90c6949c929c82d4390b2f87a420bd598275dd)

1 files changed, 395 insertions, 0 deletions

diff --git a/source3/nsswitch/smb_krb5_locator.c b/source3/nsswitch/smb_krb5_locator.c
new file mode 100644
index 0000000000..5de080c7ba
--- /dev/null
+++ b/source3/nsswitch/smb_krb5_locator.c
@@ -0,0 +1,395 @@
+/*
+   Unix SMB/CIFS implementation.
+   kerberos locator plugin
+   Copyright (C) Guenther Deschner 2007
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "nsswitch/winbind_client.h"
+
+#ifndef DEBUG_KRB5
+#undef DEBUG_KRB5
+#endif
+
+#if defined(HAVE_KRB5) && defined(HAVE_KRB5_LOCATE_PLUGIN_H)
+BOOL winbind_env_set(void);
+
+#include <krb5/locate_plugin.h>
+
+#ifndef KRB5_PLUGIN_NO_HANDLE
+#define KRB5_PLUGIN_NO_HANDLE KRB5_KDC_UNREACH /* Heimdal */
+#endif
+
+static const char *get_service_from_locate_service_type(enum locate_service_type svc)
+{
+	switch (svc) {
+		case locate_service_kdc:
+		case locate_service_master_kdc:
+			return "88";
+		case locate_service_kadmin:
+		case locate_service_krb524:
+			/* not supported */
+			return NULL;
+		case locate_service_kpasswd:
+			return "464";
+		default:
+			break;
+	}
+	return NULL;
+
+}
+
+#ifdef DEBUG_KRB5
+static const char *locate_service_type_name(enum locate_service_type svc)
+{
+	switch (svc) {
+		case locate_service_kdc:
+			return "locate_service_kdc";
+		case locate_service_master_kdc:
+			return "locate_service_master_kdc";
+		case locate_service_kadmin:
+			return "locate_service_kadmin";
+		case locate_service_krb524:
+			return "locate_service_krb524";
+		case locate_service_kpasswd:
+			return "locate_service_kpasswd";
+		default:
+			break;
+	}
+	return NULL;
+}
+
+static const char *socktype_name(int socktype)
+{
+	switch (socktype) {
+		case SOCK_STREAM:
+			return "SOCK_STREAM";
+		case SOCK_DGRAM:
+			return "SOCK_DGRAM";
+		default:
+			break;
+	}
+	return "unknown";
+}
+
+static const char *family_name(int family)
+{
+	switch (family) {
+		case AF_UNSPEC:
+			return "AF_UNSPEC";
+		case AF_INET:
+			return "AF_INET";
+		case AF_INET6:
+			return "AF_INET6";
+		default:
+			break;
+	}
+	return "unknown";
+}
+#endif
+
+/**
+ * Check input parameters, return KRB5_PLUGIN_NO_HANDLE for unsupported ones
+ *
+ * @param svc
+ * @param realm string
+ * @param socktype integer
+ * @param family integer
+ *
+ * @return integer.
+ */
+
+static int smb_krb5_locator_lookup_sanity_check(enum locate_service_type svc,
+						const char *realm,
+						int socktype,
+						int family)
+{
+	if (!realm || strlen(realm) == 0) {
+		return EINVAL;
+	}
+
+	switch (svc) {
+		case locate_service_kdc:
+		case locate_service_master_kdc:
+		case locate_service_kpasswd:
+			break;
+		case locate_service_kadmin:
+		case locate_service_krb524:
+			return KRB5_PLUGIN_NO_HANDLE;
+		default:
+			return EINVAL;
+	}
+
+	switch (family) {
+		case AF_UNSPEC:
+		case AF_INET:
+			break;
+		case AF_INET6: /* not yet */
+			return KRB5_PLUGIN_NO_HANDLE;
+		default:
+			return EINVAL;
+	}
+
+	switch (socktype) {
+		case SOCK_STREAM:
+		case SOCK_DGRAM:
+		case 0: /* Heimdal uses that */
+			break;
+		default:
+			return EINVAL;
+	}
+
+	return 0;
+}
+
+/**
+ * Try to get addrinfo for a given host and call the krb5 callback
+ *
+ * @param name string
+ * @param service string
+ * @param in struct addrinfo hint
+ * @param cbfunc krb5 callback function
+ * @param cbdata void pointer cbdata
+ *
+ * @return krb5_error_code.
+ */
+
+static krb5_error_code smb_krb5_locator_call_cbfunc(const char *name,
+						    const char *service,
+						    struct addrinfo *in,
+						    int (*cbfunc)(void *, int, struct sockaddr *),
+						    void *cbdata)
+{
+	struct addrinfo *out;
+	int ret;
+	int count = 3;
+
+	while (count) {
+
+		ret = getaddrinfo(name, service, in, &out);
+		if (ret == 0) {
+			break;
+		}
+
+		if (ret == EAI_AGAIN) {
+			count--;
+			continue;
+		}
+
+#ifdef DEBUG_KRB5
+		fprintf(stderr, "[%5u]: smb_krb5_locator_lookup: "
+			"getaddrinfo failed: %s (%d)\n",
+			(unsigned int)getpid(), gai_strerror(ret), ret);
+#endif
+
+		return KRB5_PLUGIN_NO_HANDLE;
+	}
+
+	ret = cbfunc(cbdata, out->ai_socktype, out->ai_addr);
+#ifdef DEBUG_KRB5
+	if (ret) {
+		fprintf(stderr, "[%5u]: smb_krb5_locator_lookup: "
+			"failed to call callback: %s (%d)\n",
+			(unsigned int)getpid(), error_message(ret), ret);
+	}
+#endif
+
+	freeaddrinfo(out);
+
+	return ret;
+}
+
+/**
+ * PUBLIC INTERFACE: locate init
+ *
+ * @param context krb5_context
+ * @param privata_data pointer to private data pointer
+ *
+ * @return krb5_error_code.
+ */
+
+krb5_error_code smb_krb5_locator_init(krb5_context context,
+				      void **private_data)
+{
+	return 0;
+}
+
+/**
+ * PUBLIC INTERFACE: close locate
+ *
+ * @param private_data pointer to private data
+ *
+ * @return void.
+ */
+
+void smb_krb5_locator_close(void *private_data)
+{
+	return;
+}
+
+
+static int ask_winbind(const char *realm, char **dcname)
+{
+	NSS_STATUS status;
+	struct winbindd_request request;
+	struct winbindd_response response;
+
+	ZERO_STRUCT(request);
+	ZERO_STRUCT(response);
+
+	request.flags = 0x40020600;
+			/* DS_KDC_REQUIRED |
+			DS_IS_DNS_NAME |
+			DS_RETURN_DNS_NAME |
+			DS_IP_REQUIRED */
+
+	strncpy(request.domain_name, realm,
+		sizeof(request.domain_name)-1);
+
+	status = winbindd_request_response(WINBINDD_DSGETDCNAME,
+					   &request, &response);
+	if (status != NSS_STATUS_SUCCESS) {
+#ifdef DEBUG_KRB5
+		fprintf(stderr,"[%5u]: smb_krb5_locator_lookup: failed with: %s\n",
+			(unsigned int)getpid(), nss_err_str(status));
+#endif
+		return False;
+	}
+
+	*dcname = strdup(response.data.dc_name);
+	if (!*dcname) {
+		return False;
+	}
+
+	return True;
+}
+
+/**
+ * PUBLIC INTERFACE: locate lookup
+ *
+ * @param private_data pointer to private data
+ * @param svc enum locate_service_type.
+ * @param realm string
+ * @param socktype integer
+ * @param family integer
+ * @param cbfunc callback function to send back entries
+ * @param cbdata void pointer to cbdata
+ *
+ * @return krb5_error_code.
+ */
+
+krb5_error_code smb_krb5_locator_lookup(void *private_data,
+					enum locate_service_type svc,
+					const char *realm,
+					int socktype,
+					int family,
+					int (*cbfunc)(void *, int, struct sockaddr *),
+					void *cbdata)
+{
+	krb5_error_code ret;
+	struct addrinfo aihints;
+	char *kdc_name = NULL;
+	const char *service = get_service_from_locate_service_type(svc);
+
+	ZERO_STRUCT(aihints);
+
+#ifdef DEBUG_KRB5
+	fprintf(stderr,"[%5u]: smb_krb5_locator_lookup: called for '%s' "
+			"svc: '%s' (%d) "
+			"socktype: '%s' (%d), family: '%s' (%d)\n",
+			(unsigned int)getpid(), realm,
+			locate_service_type_name(svc), svc,
+			socktype_name(socktype), socktype,
+		        family_name(family), family);
+#endif
+	ret = smb_krb5_locator_lookup_sanity_check(svc, realm, socktype,
+						   family);
+	if (ret) {
+#ifdef DEBUG_KRB5
+		fprintf(stderr, "[%5u]: smb_krb5_locator_lookup: "
+			"returning ret: %s (%d)\n",
+			(unsigned int)getpid(), error_message(ret), ret);
+#endif
+		return ret;
+	}
+
+	if (!winbind_env_set()) {
+		if (!ask_winbind(realm, &kdc_name)) {
+#ifdef DEBUG_KRB5
+			fprintf(stderr, "[%5u]: smb_krb5_locator_lookup: "
+				"failed to query winbindd\n",
+				(unsigned int)getpid());
+#endif
+			goto failed;
+		}
+	} else {
+		const char *env = NULL;
+		char *var = NULL;
+		if (asprintf(&var, "%s_%s",
+			     WINBINDD_LOCATOR_KDC_ADDRESS, realm) == -1) {
+			goto failed;
+		}
+		env = getenv(var);
+		if (!env) {
+#ifdef DEBUG_KRB5
+			fprintf(stderr, "[%5u]: smb_krb5_locator_lookup: "
+				"failed to get kdc from env %s\n",
+				(unsigned int)getpid(), var);
+#endif
+			free(var);
+			goto failed;
+		}
+		free(var);
+
+		kdc_name = strdup(env);
+		if (!kdc_name) {
+			goto failed;
+		}
+	}
+#ifdef DEBUG_KRB5
+	fprintf(stderr, "[%5u]: smb_krb5_locator_lookup: "
+		"got '%s' for '%s' from winbindd\n", (unsigned int)getpid(),
+		kdc_name, realm);
+#endif
+
+	aihints.ai_family = family;
+	aihints.ai_socktype = socktype;
+
+	ret = smb_krb5_locator_call_cbfunc(kdc_name,
+					   service,
+					   &aihints,
+					   cbfunc, cbdata);
+	SAFE_FREE(kdc_name);
+
+	return ret;
+
+ failed:
+	return KRB5_PLUGIN_NO_HANDLE;
+}
+
+#ifdef HEIMDAL_KRB5_LOCATE_PLUGIN_H
+#define SMB_KRB5_LOCATOR_SYMBOL_NAME resolve /* Heimdal */
+#else
+#define SMB_KRB5_LOCATOR_SYMBOL_NAME service_locator /* MIT */
+#endif
+
+const krb5plugin_service_locate_ftable SMB_KRB5_LOCATOR_SYMBOL_NAME = {
+	0, /* version */
+	smb_krb5_locator_init,
+	smb_krb5_locator_close,
+	smb_krb5_locator_lookup,
+};
+
+#endif