xref: /titanic_51/usr/src/lib/smbsrv/libmlrpc/common/ndr_client.c (revision b453864f3587ccc3324d7a3b0438a1e542dcfde7)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <sys/errno.h>
27 #include <string.h>
28 #include <strings.h>
29 
30 #include <smbsrv/libsmb.h>
31 #include <smbsrv/libmlrpc.h>
32 
33 #define	NDR_IS_LAST_FRAG(F)	((F) & NDR_PFC_LAST_FRAG)
34 #define	NDR_DEFAULT_FRAGSZ	8192
35 
36 static void ndr_clnt_init_hdr(ndr_client_t *, ndr_xa_t *);
37 static int ndr_clnt_get_frags(ndr_client_t *, ndr_xa_t *);
38 static void ndr_clnt_remove_hdr(ndr_stream_t *, int *);
39 
40 int
41 ndr_clnt_bind(ndr_client_t *clnt, const char *service_name,
42     ndr_binding_t **ret_binding_p)
43 {
44 	ndr_service_t		*msvc;
45 	ndr_binding_t		*mbind;
46 	ndr_xa_t		mxa;
47 	ndr_bind_hdr_t		*bhdr;
48 	ndr_p_cont_elem_t 	*pce;
49 	ndr_bind_ack_hdr_t	*bahdr;
50 	ndr_p_result_t		*pre;
51 	int			rc;
52 
53 	bzero(&mxa, sizeof (mxa));
54 
55 	msvc = ndr_svc_lookup_name(service_name);
56 	if (msvc == NULL)
57 		return (NDR_DRC_FAULT_API_SERVICE_INVALID);
58 
59 	mxa.binding_list = clnt->binding_list;
60 	if ((mbind = ndr_svc_new_binding(&mxa)) == NULL)
61 		return (NDR_DRC_FAULT_API_BIND_NO_SLOTS);
62 
63 	ndr_clnt_init_hdr(clnt, &mxa);
64 
65 	bhdr = &mxa.send_hdr.bind_hdr;
66 	bhdr->common_hdr.ptype = NDR_PTYPE_BIND;
67 	bhdr->common_hdr.frag_length = sizeof (*bhdr);
68 	bhdr->max_xmit_frag = NDR_DEFAULT_FRAGSZ;
69 	bhdr->max_recv_frag = NDR_DEFAULT_FRAGSZ;
70 	bhdr->assoc_group_id = 0;
71 	bhdr->p_context_elem.n_context_elem = 1;
72 
73 	/* Assign presentation context id */
74 	pce = &bhdr->p_context_elem.p_cont_elem[0];
75 	pce->p_cont_id = clnt->next_p_cont_id++;
76 	pce->n_transfer_syn = 1;
77 
78 	/* Set up UUIDs and versions from the service */
79 	pce->abstract_syntax.if_version = msvc->abstract_syntax_version;
80 	rc = ndr_uuid_parse(msvc->abstract_syntax_uuid,
81 	    &pce->abstract_syntax.if_uuid);
82 	if (rc != 0)
83 		return (NDR_DRC_FAULT_API_SERVICE_INVALID);
84 
85 	pce->transfer_syntaxes[0].if_version = msvc->transfer_syntax_version;
86 	rc = ndr_uuid_parse(msvc->transfer_syntax_uuid,
87 	    &pce->transfer_syntaxes[0].if_uuid);
88 	if (rc != 0)
89 		return (NDR_DRC_FAULT_API_SERVICE_INVALID);
90 
91 	/* Format and exchange the PDU */
92 
93 	if ((*clnt->xa_init)(clnt, &mxa) < 0)
94 		return (NDR_DRC_FAULT_OUT_OF_MEMORY);
95 
96 	rc = ndr_encode_pdu_hdr(&mxa);
97 	if (NDR_DRC_IS_FAULT(rc))
98 		goto fault_exit;
99 
100 	if ((*clnt->xa_exchange)(clnt, &mxa) < 0) {
101 		rc = NDR_DRC_FAULT_SEND_FAILED;
102 		goto fault_exit;
103 	}
104 
105 	rc = ndr_decode_pdu_hdr(&mxa);
106 	if (NDR_DRC_IS_FAULT(rc))
107 		goto fault_exit;
108 
109 	/* done with buffers */
110 	(*clnt->xa_destruct)(clnt, &mxa);
111 
112 	bahdr = &mxa.recv_hdr.bind_ack_hdr;
113 
114 	if (mxa.ptype != NDR_PTYPE_BIND_ACK)
115 		return (NDR_DRC_FAULT_RECEIVED_MALFORMED);
116 
117 	if (bahdr->p_result_list.n_results != 1)
118 		return (NDR_DRC_FAULT_RECEIVED_MALFORMED);
119 
120 	pre = &bahdr->p_result_list.p_results[0];
121 
122 	if (pre->result != NDR_PCDR_ACCEPTANCE)
123 		return (NDR_DRC_FAULT_RECEIVED_MALFORMED);
124 
125 	mbind->p_cont_id = pce->p_cont_id;
126 	mbind->which_side = NDR_BIND_SIDE_CLIENT;
127 	mbind->clnt = clnt;
128 	mbind->service = msvc;
129 	mbind->instance_specific = 0;
130 
131 	*ret_binding_p = mbind;
132 	return (NDR_DRC_OK);
133 
134 fault_exit:
135 	(*clnt->xa_destruct)(clnt, &mxa);
136 	return (rc);
137 }
138 
139 int
140 ndr_clnt_call(ndr_binding_t *mbind, int opnum, void *params)
141 {
142 	ndr_client_t		*clnt = mbind->clnt;
143 	ndr_service_t		*msvc = mbind->service;
144 	ndr_xa_t		mxa;
145 	ndr_request_hdr_t	*reqhdr;
146 	ndr_common_header_t	*rsphdr;
147 	unsigned long		recv_pdu_scan_offset;
148 	int			rc;
149 
150 	if (ndr_svc_find_stub(msvc, opnum) == NULL)
151 		return (NDR_DRC_FAULT_API_OPNUM_INVALID);
152 
153 	bzero(&mxa, sizeof (mxa));
154 	mxa.ptype = NDR_PTYPE_REQUEST;
155 	mxa.opnum = opnum;
156 	mxa.binding = mbind;
157 
158 	ndr_clnt_init_hdr(clnt, &mxa);
159 
160 	reqhdr = &mxa.send_hdr.request_hdr;
161 	reqhdr->common_hdr.ptype = NDR_PTYPE_REQUEST;
162 	reqhdr->p_cont_id = mbind->p_cont_id;
163 	reqhdr->opnum = opnum;
164 
165 	rc = (*clnt->xa_init)(clnt, &mxa);
166 	if (NDR_DRC_IS_FAULT(rc))
167 		return (rc);
168 
169 	/* Reserve room for hdr */
170 	mxa.send_nds.pdu_scan_offset = sizeof (*reqhdr);
171 
172 	rc = ndr_encode_call(&mxa, params);
173 	if (!NDR_DRC_IS_OK(rc))
174 		goto fault_exit;
175 
176 	mxa.send_nds.pdu_scan_offset = 0;
177 
178 	/*
179 	 * Now we have the PDU size, we need to set up the
180 	 * frag_length and calculate the alloc_hint.
181 	 */
182 	mxa.send_hdr.common_hdr.frag_length = mxa.send_nds.pdu_size;
183 	reqhdr->alloc_hint = mxa.send_nds.pdu_size -
184 	    sizeof (ndr_request_hdr_t);
185 
186 	rc = ndr_encode_pdu_hdr(&mxa);
187 	if (NDR_DRC_IS_FAULT(rc))
188 		goto fault_exit;
189 
190 	rc = (*clnt->xa_exchange)(clnt, &mxa);
191 	if (NDR_DRC_IS_FAULT(rc))
192 		goto fault_exit;
193 
194 	rc = ndr_decode_pdu_hdr(&mxa);
195 	if (NDR_DRC_IS_FAULT(rc))
196 		goto fault_exit;
197 
198 	if (mxa.ptype != NDR_PTYPE_RESPONSE) {
199 		rc = NDR_DRC_FAULT_RECEIVED_MALFORMED;
200 		goto fault_exit;
201 	}
202 
203 	rsphdr = &mxa.recv_hdr.common_hdr;
204 
205 	if (!NDR_IS_LAST_FRAG(rsphdr->pfc_flags)) {
206 		/*
207 		 * This is a multi-fragment response.
208 		 * Preserve the current scan offset while getting
209 		 * fragments so that we can continue afterward
210 		 * as if we had received the entire response as
211 		 * a single PDU.
212 		 */
213 		recv_pdu_scan_offset = mxa.recv_nds.pdu_scan_offset;
214 
215 		if (ndr_clnt_get_frags(clnt, &mxa) < 0) {
216 			rc = NDR_DRC_FAULT_RECEIVED_MALFORMED;
217 			goto fault_exit;
218 		}
219 
220 		mxa.recv_nds.pdu_scan_offset = recv_pdu_scan_offset;
221 	}
222 
223 	rc = ndr_decode_return(&mxa, params);
224 	if (NDR_DRC_IS_FAULT(rc))
225 		goto fault_exit;
226 
227 	(*clnt->xa_preserve)(clnt, &mxa);
228 	(*clnt->xa_destruct)(clnt, &mxa);
229 	return (NDR_DRC_OK);
230 
231 fault_exit:
232 	(*clnt->xa_destruct)(clnt, &mxa);
233 	return (rc);
234 }
235 
236 void
237 ndr_clnt_free_heap(ndr_client_t *clnt)
238 {
239 	(*clnt->xa_release)(clnt);
240 }
241 
242 static void
243 ndr_clnt_init_hdr(ndr_client_t *clnt, ndr_xa_t *mxa)
244 {
245 	ndr_common_header_t *hdr = &mxa->send_hdr.common_hdr;
246 
247 	hdr->rpc_vers = 5;
248 	hdr->rpc_vers_minor = 0;
249 	hdr->pfc_flags = NDR_PFC_FIRST_FRAG + NDR_PFC_LAST_FRAG;
250 	hdr->packed_drep.intg_char_rep = NDR_REPLAB_CHAR_ASCII;
251 #ifndef _BIG_ENDIAN
252 	hdr->packed_drep.intg_char_rep |= NDR_REPLAB_INTG_LITTLE_ENDIAN;
253 #endif
254 	/* hdr->frag_length */
255 	hdr->auth_length = 0;
256 	hdr->call_id = clnt->next_call_id++;
257 }
258 
259 /*
260  * ndr_clnt_remove_hdr
261  *
262  * Remove an RPC fragment header from the received data stream.
263  *
264  * Original RPC receive buffer:
265  * |-      frag1                   -|    |-frag M(partial)-|
266  * +==================+=============+----+=================+
267  * | SmbTransact Rsp1 | SmbTransact |    | SmbReadX RspN   |
268  * | (with RPC hdr)   | Rsp2        | .. | (with RPC hdr)  |
269  * +-----+------------+-------------+    +-----+-----------+
270  * | hdr | data       | data        | .. | hdr | data      |
271  * +=====+============+=============+----+=====+===========+
272  *                                       <------
273  * ^                                     ^     ^
274  * |                                     |     |
275  * base_offset                          hdr   data
276  *
277  * |-------------------------------------|-----------------|
278  *              offset                           len
279  *
280  * RPC receive buffer (after this call):
281  * +==================+=============+----+===========+
282  * | SmbTransact Rsp1 | SmbTransact |    | SmbReadX  |
283  * | (with RPC hdr)   | Rsp2        | .. | RspN      |
284  * +-----+------------+-------------+    +-----------+
285  * | hdr | data       | data        | .. | data      |
286  * +=====+============+=============+----+===========+
287  */
288 static void
289 ndr_clnt_remove_hdr(ndr_stream_t *nds, int *nbytes)
290 {
291 	char *hdr;
292 	char *data;
293 
294 	hdr = (char *)nds->pdu_base_offset + nds->pdu_scan_offset;
295 	data = hdr + NDR_RSP_HDR_SIZE;
296 	*nbytes -= NDR_RSP_HDR_SIZE;
297 
298 	bcopy(data, hdr, *nbytes);
299 	nds->pdu_size -= NDR_RSP_HDR_SIZE;
300 }
301 
302 /*
303  * ndr_clnt_get_frags
304  *
305  * A DCE RPC message that is larger than a single fragment is transmitted
306  * as a series of fragments: 5280 bytes for Windows NT and 4280 bytes for
307  * both Windows 2000 and 2003.
308  *
309  * Collect RPC fragments and append them to the receive stream buffer.
310  * Each received fragment has a header, which we need to remove as we
311  * build the full RPC PDU.
312  *
313  * The xa_read() calls will translate to SmbReadX requests.  Note that
314  * there is no correspondence between SmbReadX buffering and DCE RPC
315  * fragment alignment.
316  *
317  * Return -1 on error. Otherwise, return the total data count of the
318  * complete RPC response upon success.
319  */
320 static int
321 ndr_clnt_get_frags(ndr_client_t *clnt, ndr_xa_t *mxa)
322 {
323 	ndr_stream_t *nds = &mxa->recv_nds;
324 	ndr_common_header_t hdr;
325 	int frag_rcvd;
326 	int frag_size;
327 	int last_frag;
328 	int nbytes;
329 
330 	/*
331 	 * The scan offest will be used to locate the frag header.
332 	 */
333 	nds->pdu_scan_offset = nds->pdu_base_offset + nds->pdu_size;
334 
335 	do {
336 		frag_rcvd = 0;
337 
338 		do {
339 			if ((nbytes = (*clnt->xa_read)(clnt, mxa)) < 0)
340 				return (-1);
341 
342 			if (frag_rcvd == 0) {
343 				ndr_decode_frag_hdr(nds, &hdr);
344 
345 				last_frag = NDR_IS_LAST_FRAG(hdr.pfc_flags);
346 				frag_size = hdr.frag_length - NDR_RSP_HDR_SIZE;
347 
348 				ndr_clnt_remove_hdr(nds, &nbytes);
349 				nds->pdu_scan_offset += frag_size;
350 			}
351 
352 			frag_rcvd += nbytes;
353 
354 		} while (frag_rcvd < frag_size);
355 	} while (!last_frag);
356 
357 	return (0);
358 }
359