xref: /titanic_50/usr/src/lib/smbsrv/libmlrpc/common/ndr_client.c (revision 7ff836697c120cb94bd30d5c2204eb9b74718e4c)
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 2009 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_DEFAULT_FRAGSZ	8192
34 
35 static void ndr_clnt_init_hdr(ndr_client_t *, ndr_xa_t *);
36 static int ndr_clnt_get_frags(ndr_client_t *, ndr_xa_t *);
37 static void ndr_clnt_remove_hdr(ndr_stream_t *, int *);
38 
39 int
40 ndr_clnt_bind(ndr_client_t *clnt, const char *service_name,
41     ndr_binding_t **ret_binding_p)
42 {
43 	ndr_service_t		*msvc;
44 	ndr_binding_t		*mbind;
45 	ndr_xa_t		mxa;
46 	ndr_bind_hdr_t		*bhdr;
47 	ndr_p_cont_elem_t 	*pce;
48 	ndr_bind_ack_hdr_t	*bahdr;
49 	ndr_p_result_t		*pre;
50 	int			rc;
51 
52 	bzero(&mxa, sizeof (mxa));
53 
54 	msvc = ndr_svc_lookup_name(service_name);
55 	if (msvc == NULL)
56 		return (NDR_DRC_FAULT_API_SERVICE_INVALID);
57 
58 	mxa.binding_list = clnt->binding_list;
59 	if ((mbind = ndr_svc_new_binding(&mxa)) == NULL)
60 		return (NDR_DRC_FAULT_API_BIND_NO_SLOTS);
61 
62 	ndr_clnt_init_hdr(clnt, &mxa);
63 
64 	bhdr = &mxa.send_hdr.bind_hdr;
65 	bhdr->common_hdr.ptype = NDR_PTYPE_BIND;
66 	bhdr->common_hdr.frag_length = sizeof (*bhdr);
67 	bhdr->max_xmit_frag = NDR_DEFAULT_FRAGSZ;
68 	bhdr->max_recv_frag = NDR_DEFAULT_FRAGSZ;
69 	bhdr->assoc_group_id = 0;
70 	bhdr->p_context_elem.n_context_elem = 1;
71 
72 	/* Assign presentation context id */
73 	pce = &bhdr->p_context_elem.p_cont_elem[0];
74 	pce->p_cont_id = clnt->next_p_cont_id++;
75 	pce->n_transfer_syn = 1;
76 
77 	/* Set up UUIDs and versions from the service */
78 	pce->abstract_syntax.if_version = msvc->abstract_syntax_version;
79 	rc = ndr_uuid_parse(msvc->abstract_syntax_uuid,
80 	    &pce->abstract_syntax.if_uuid);
81 	if (rc != 0)
82 		return (NDR_DRC_FAULT_API_SERVICE_INVALID);
83 
84 	pce->transfer_syntaxes[0].if_version = msvc->transfer_syntax_version;
85 	rc = ndr_uuid_parse(msvc->transfer_syntax_uuid,
86 	    &pce->transfer_syntaxes[0].if_uuid);
87 	if (rc != 0)
88 		return (NDR_DRC_FAULT_API_SERVICE_INVALID);
89 
90 	/* Format and exchange the PDU */
91 
92 	if ((*clnt->xa_init)(clnt, &mxa) < 0)
93 		return (NDR_DRC_FAULT_OUT_OF_MEMORY);
94 
95 	rc = ndr_encode_pdu_hdr(&mxa);
96 	if (NDR_DRC_IS_FAULT(rc))
97 		goto fault_exit;
98 
99 	if ((*clnt->xa_exchange)(clnt, &mxa) < 0) {
100 		rc = NDR_DRC_FAULT_SEND_FAILED;
101 		goto fault_exit;
102 	}
103 
104 	rc = ndr_decode_pdu_hdr(&mxa);
105 	if (NDR_DRC_IS_FAULT(rc))
106 		goto fault_exit;
107 
108 	/* done with buffers */
109 	(*clnt->xa_destruct)(clnt, &mxa);
110 
111 	bahdr = &mxa.recv_hdr.bind_ack_hdr;
112 
113 	if (mxa.ptype != NDR_PTYPE_BIND_ACK)
114 		return (NDR_DRC_FAULT_RECEIVED_MALFORMED);
115 
116 	if (bahdr->p_result_list.n_results != 1)
117 		return (NDR_DRC_FAULT_RECEIVED_MALFORMED);
118 
119 	pre = &bahdr->p_result_list.p_results[0];
120 
121 	if (pre->result != NDR_PCDR_ACCEPTANCE)
122 		return (NDR_DRC_FAULT_RECEIVED_MALFORMED);
123 
124 	mbind->p_cont_id = pce->p_cont_id;
125 	mbind->which_side = NDR_BIND_SIDE_CLIENT;
126 	mbind->clnt = clnt;
127 	mbind->service = msvc;
128 	mbind->instance_specific = 0;
129 
130 	*ret_binding_p = mbind;
131 	return (NDR_DRC_OK);
132 
133 fault_exit:
134 	(*clnt->xa_destruct)(clnt, &mxa);
135 	return (rc);
136 }
137 
138 int
139 ndr_clnt_call(ndr_binding_t *mbind, int opnum, void *params)
140 {
141 	ndr_client_t		*clnt = mbind->clnt;
142 	ndr_service_t		*msvc = mbind->service;
143 	ndr_xa_t		mxa;
144 	ndr_request_hdr_t	*reqhdr;
145 	ndr_common_header_t	*rsphdr;
146 	unsigned long		recv_pdu_scan_offset;
147 	int			rc;
148 
149 	if (ndr_svc_lookup_name(msvc->name) == NULL)
150 		return (NDR_DRC_FAULT_API_SERVICE_INVALID);
151 
152 	bzero(&mxa, sizeof (mxa));
153 	mxa.ptype = NDR_PTYPE_REQUEST;
154 	mxa.opnum = opnum;
155 	mxa.binding = mbind;
156 
157 	ndr_clnt_init_hdr(clnt, &mxa);
158 
159 	reqhdr = &mxa.send_hdr.request_hdr;
160 	reqhdr->common_hdr.ptype = NDR_PTYPE_REQUEST;
161 	reqhdr->p_cont_id = mbind->p_cont_id;
162 	reqhdr->opnum = opnum;
163 
164 	rc = (*clnt->xa_init)(clnt, &mxa);
165 	if (NDR_DRC_IS_FAULT(rc))
166 		return (rc);
167 
168 	/* Reserve room for hdr */
169 	mxa.send_nds.pdu_scan_offset = sizeof (*reqhdr);
170 
171 	rc = ndr_encode_call(&mxa, params);
172 	if (!NDR_DRC_IS_OK(rc))
173 		goto fault_exit;
174 
175 	mxa.send_nds.pdu_scan_offset = 0;
176 
177 	/*
178 	 * Now we have the PDU size, we need to set up the
179 	 * frag_length and calculate the alloc_hint.
180 	 */
181 	mxa.send_hdr.common_hdr.frag_length = mxa.send_nds.pdu_size;
182 	reqhdr->alloc_hint = mxa.send_nds.pdu_size -
183 	    sizeof (ndr_request_hdr_t);
184 
185 	rc = ndr_encode_pdu_hdr(&mxa);
186 	if (NDR_DRC_IS_FAULT(rc))
187 		goto fault_exit;
188 
189 	rc = (*clnt->xa_exchange)(clnt, &mxa);
190 	if (NDR_DRC_IS_FAULT(rc))
191 		goto fault_exit;
192 
193 	rc = ndr_decode_pdu_hdr(&mxa);
194 	if (NDR_DRC_IS_FAULT(rc))
195 		goto fault_exit;
196 
197 	if (mxa.ptype != NDR_PTYPE_RESPONSE) {
198 		rc = NDR_DRC_FAULT_RECEIVED_MALFORMED;
199 		goto fault_exit;
200 	}
201 
202 	rsphdr = &mxa.recv_hdr.common_hdr;
203 
204 	if (!NDR_IS_LAST_FRAG(rsphdr->pfc_flags)) {
205 		/*
206 		 * This is a multi-fragment response.
207 		 * Preserve the current scan offset while getting
208 		 * fragments so that we can continue afterward
209 		 * as if we had received the entire response as
210 		 * a single PDU.
211 		 */
212 		recv_pdu_scan_offset = mxa.recv_nds.pdu_scan_offset;
213 
214 		if (ndr_clnt_get_frags(clnt, &mxa) < 0) {
215 			rc = NDR_DRC_FAULT_RECEIVED_MALFORMED;
216 			goto fault_exit;
217 		}
218 
219 		mxa.recv_nds.pdu_scan_offset = recv_pdu_scan_offset;
220 	}
221 
222 	rc = ndr_decode_return(&mxa, params);
223 	if (NDR_DRC_IS_FAULT(rc))
224 		goto fault_exit;
225 
226 	(*clnt->xa_preserve)(clnt, &mxa);
227 	(*clnt->xa_destruct)(clnt, &mxa);
228 	return (NDR_DRC_OK);
229 
230 fault_exit:
231 	(*clnt->xa_destruct)(clnt, &mxa);
232 	return (rc);
233 }
234 
235 void
236 ndr_clnt_free_heap(ndr_client_t *clnt)
237 {
238 	(*clnt->xa_release)(clnt);
239 }
240 
241 static void
242 ndr_clnt_init_hdr(ndr_client_t *clnt, ndr_xa_t *mxa)
243 {
244 	ndr_common_header_t *hdr = &mxa->send_hdr.common_hdr;
245 
246 	hdr->rpc_vers = 5;
247 	hdr->rpc_vers_minor = 0;
248 	hdr->pfc_flags = NDR_PFC_FIRST_FRAG + NDR_PFC_LAST_FRAG;
249 	hdr->packed_drep.intg_char_rep = NDR_REPLAB_CHAR_ASCII;
250 #ifndef _BIG_ENDIAN
251 	hdr->packed_drep.intg_char_rep |= NDR_REPLAB_INTG_LITTLE_ENDIAN;
252 #endif
253 	/* hdr->frag_length */
254 	hdr->auth_length = 0;
255 	hdr->call_id = clnt->next_call_id++;
256 }
257 
258 /*
259  * ndr_clnt_remove_hdr
260  *
261  * Remove an RPC fragment header from the received data stream.
262  *
263  * Original RPC receive buffer:
264  * |-      frag1                   -|    |-frag M(partial)-|
265  * +==================+=============+----+=================+
266  * | SmbTransact Rsp1 | SmbTransact |    | SmbReadX RspN   |
267  * | (with RPC hdr)   | Rsp2        | .. | (with RPC hdr)  |
268  * +-----+------------+-------------+    +-----+-----------+
269  * | hdr | data       | data        | .. | hdr | data      |
270  * +=====+============+=============+----+=====+===========+
271  *                                       <------
272  * ^                                     ^     ^
273  * |                                     |     |
274  * base_offset                          hdr   data
275  *
276  * |-------------------------------------|-----------------|
277  *              offset                           len
278  *
279  * RPC receive buffer (after this call):
280  * +==================+=============+----+===========+
281  * | SmbTransact Rsp1 | SmbTransact |    | SmbReadX  |
282  * | (with RPC hdr)   | Rsp2        | .. | RspN      |
283  * +-----+------------+-------------+    +-----------+
284  * | hdr | data       | data        | .. | data      |
285  * +=====+============+=============+----+===========+
286  */
287 static void
288 ndr_clnt_remove_hdr(ndr_stream_t *nds, int *nbytes)
289 {
290 	char *hdr;
291 	char *data;
292 
293 	hdr = (char *)nds->pdu_base_offset + nds->pdu_scan_offset;
294 	data = hdr + NDR_RSP_HDR_SIZE;
295 	*nbytes -= NDR_RSP_HDR_SIZE;
296 
297 	bcopy(data, hdr, *nbytes);
298 	nds->pdu_size -= NDR_RSP_HDR_SIZE;
299 }
300 
301 /*
302  * ndr_clnt_get_frags
303  *
304  * A DCE RPC message that is larger than a single fragment is transmitted
305  * as a series of fragments: 5280 bytes for Windows NT and 4280 bytes for
306  * both Windows 2000 and 2003.
307  *
308  * Collect RPC fragments and append them to the receive stream buffer.
309  * Each received fragment has a header, which we need to remove as we
310  * build the full RPC PDU.
311  *
312  * The xa_read() calls will translate to SmbReadX requests.  Note that
313  * there is no correspondence between SmbReadX buffering and DCE RPC
314  * fragment alignment.
315  *
316  * Return -1 on error. Otherwise, return the total data count of the
317  * complete RPC response upon success.
318  */
319 static int
320 ndr_clnt_get_frags(ndr_client_t *clnt, ndr_xa_t *mxa)
321 {
322 	ndr_stream_t *nds = &mxa->recv_nds;
323 	ndr_common_header_t hdr;
324 	int frag_rcvd;
325 	int frag_size;
326 	int last_frag;
327 	int nbytes;
328 
329 	/*
330 	 * The scan offest will be used to locate the frag header.
331 	 */
332 	nds->pdu_scan_offset = nds->pdu_base_offset + nds->pdu_size;
333 
334 	do {
335 		frag_rcvd = 0;
336 
337 		do {
338 			if ((nbytes = (*clnt->xa_read)(clnt, mxa)) < 0)
339 				return (-1);
340 
341 			if (frag_rcvd == 0) {
342 				ndr_decode_frag_hdr(nds, &hdr);
343 
344 				last_frag = NDR_IS_LAST_FRAG(hdr.pfc_flags);
345 				frag_size = hdr.frag_length - NDR_RSP_HDR_SIZE;
346 
347 				ndr_clnt_remove_hdr(nds, &nbytes);
348 				nds->pdu_scan_offset += frag_size;
349 			}
350 
351 			frag_rcvd += nbytes;
352 
353 		} while (frag_rcvd < frag_size);
354 	} while (!last_frag);
355 
356 	return (0);
357 }
358