2 Unix SMB/CIFS implementation.
4 Copyright (C) Andrew Tridgell 2003
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 this file implements functions for manipulating the 'struct smbsrv_request' structure in smbd
26 #include "smb_server/smb_server.h"
27 #include "smbd/service_stream.h"
28 #include "lib/stream/packet.h"
29 #include "ntvfs/ntvfs.h"
32 /* we over allocate the data buffer to prevent too many realloc calls */
33 #define REQ_OVER_ALLOCATION 0
35 /****************************************************************************
36 construct a basic request packet, mostly used to construct async packets
37 such as change notify and oplock break requests
38 ****************************************************************************/
39 struct smbsrv_request *smbsrv_init_request(struct smbsrv_connection *smb_conn)
41 struct smbsrv_request *req;
43 req = talloc_zero(smb_conn, struct smbsrv_request);
48 /* setup the request context */
49 req->smb_conn = smb_conn;
56 setup a chained reply in req->out with the given word count and initial data buffer size.
58 static void req_setup_chain_reply(struct smbsrv_request *req, uint_t wct, uint_t buflen)
60 uint32_t chain_base_size = req->out.size;
62 /* we need room for the wct value, the words, the buffer length and the buffer */
63 req->out.size += 1 + VWV(wct) + 2 + buflen;
65 /* over allocate by a small amount */
66 req->out.allocated = req->out.size + REQ_OVER_ALLOCATION;
68 req->out.buffer = talloc_realloc(req, req->out.buffer,
69 uint8_t, req->out.allocated);
70 if (!req->out.buffer) {
71 smbsrv_terminate_connection(req->smb_conn, "allocation failed");
75 req->out.hdr = req->out.buffer + NBT_HDR_SIZE;
76 req->out.vwv = req->out.buffer + chain_base_size + 1;
78 req->out.data = req->out.vwv + VWV(wct) + 2;
79 req->out.data_size = buflen;
80 req->out.ptr = req->out.data;
82 SCVAL(req->out.buffer, chain_base_size, wct);
83 SSVAL(req->out.vwv, VWV(wct), buflen);
88 setup a reply in req->out with the given word count and initial data buffer size.
89 the caller will then fill in the command words and data before calling req_send_reply() to
90 send the reply on its way
92 void smbsrv_setup_reply(struct smbsrv_request *req, uint_t wct, uint_t buflen)
96 if (req->chain_count != 0) {
97 req_setup_chain_reply(req, wct, buflen);
101 req->out.size = NBT_HDR_SIZE + MIN_SMB_SIZE + VWV(wct) + buflen;
103 /* over allocate by a small amount */
104 req->out.allocated = req->out.size + REQ_OVER_ALLOCATION;
106 req->out.buffer = talloc_size(req, req->out.allocated);
107 if (!req->out.buffer) {
108 smbsrv_terminate_connection(req->smb_conn, "allocation failed");
112 flags2 = FLAGS2_LONG_PATH_COMPONENTS |
113 FLAGS2_EXTENDED_ATTRIBUTES |
115 flags2 |= (req->flags2 & (FLAGS2_UNICODE_STRINGS|FLAGS2_EXTENDED_SECURITY));
116 if (req->smb_conn->negotiate.client_caps & CAP_STATUS32) {
117 flags2 |= FLAGS2_32_BIT_ERROR_CODES;
120 req->out.hdr = req->out.buffer + NBT_HDR_SIZE;
121 req->out.vwv = req->out.hdr + HDR_VWV;
123 req->out.data = req->out.vwv + VWV(wct) + 2;
124 req->out.data_size = buflen;
125 req->out.ptr = req->out.data;
127 SIVAL(req->out.hdr, HDR_RCLS, 0);
129 SCVAL(req->out.hdr, HDR_WCT, wct);
130 SSVAL(req->out.vwv, VWV(wct), buflen);
132 memcpy(req->out.hdr, "\377SMB", 4);
133 SCVAL(req->out.hdr,HDR_FLG, FLAG_REPLY | FLAG_CASELESS_PATHNAMES);
134 SSVAL(req->out.hdr,HDR_FLG2, flags2);
135 SSVAL(req->out.hdr,HDR_PIDHIGH,0);
136 memset(req->out.hdr + HDR_SS_FIELD, 0, 10);
139 /* copy the cmd, tid, pid, uid and mid from the request */
140 SCVAL(req->out.hdr,HDR_COM,CVAL(req->in.hdr,HDR_COM));
141 SSVAL(req->out.hdr,HDR_TID,SVAL(req->in.hdr,HDR_TID));
142 SSVAL(req->out.hdr,HDR_PID,SVAL(req->in.hdr,HDR_PID));
143 SSVAL(req->out.hdr,HDR_UID,SVAL(req->in.hdr,HDR_UID));
144 SSVAL(req->out.hdr,HDR_MID,SVAL(req->in.hdr,HDR_MID));
146 SCVAL(req->out.hdr,HDR_COM,0);
147 SSVAL(req->out.hdr,HDR_TID,0);
148 SSVAL(req->out.hdr,HDR_PID,0);
149 SSVAL(req->out.hdr,HDR_UID,0);
150 SSVAL(req->out.hdr,HDR_MID,0);
156 setup a copy of a request, used when the server needs to send
157 more than one reply for a single request packet
159 struct smbsrv_request *smbsrv_setup_secondary_request(struct smbsrv_request *old_req)
161 struct smbsrv_request *req;
164 req = talloc_memdup(old_req, old_req, sizeof(struct smbsrv_request));
169 req->out.buffer = talloc_memdup(req, req->out.buffer, req->out.allocated);
170 if (req->out.buffer == NULL) {
175 diff = req->out.buffer - old_req->out.buffer;
177 req->out.hdr += diff;
178 req->out.vwv += diff;
179 req->out.data += diff;
180 req->out.ptr += diff;
186 work out the maximum data size we will allow for this reply, given
187 the negotiated max_xmit. The basic reply packet must be setup before
190 note that this is deliberately a signed integer reply
192 int req_max_data(struct smbsrv_request *req)
195 ret = req->smb_conn->negotiate.max_send;
196 ret -= PTR_DIFF(req->out.data, req->out.hdr);
197 if (ret < 0) ret = 0;
203 grow the allocation of the data buffer portion of a reply
204 packet. Note that as this can reallocate the packet buffer this
205 invalidates any local pointers into the packet.
207 To cope with this req->out.ptr is supplied. This will be updated to
208 point at the same offset into the packet as before this call
210 static void req_grow_allocation(struct smbsrv_request *req, uint_t new_size)
215 delta = new_size - req->out.data_size;
216 if (delta + req->out.size <= req->out.allocated) {
217 /* it fits in the preallocation */
221 /* we need to realloc */
222 req->out.allocated = req->out.size + delta + REQ_OVER_ALLOCATION;
223 buf2 = talloc_realloc(req, req->out.buffer, uint8_t, req->out.allocated);
225 smb_panic("out of memory in req_grow_allocation");
228 if (buf2 == req->out.buffer) {
229 /* the malloc library gave us the same pointer */
233 /* update the pointers into the packet */
234 req->out.data = buf2 + PTR_DIFF(req->out.data, req->out.buffer);
235 req->out.ptr = buf2 + PTR_DIFF(req->out.ptr, req->out.buffer);
236 req->out.vwv = buf2 + PTR_DIFF(req->out.vwv, req->out.buffer);
237 req->out.hdr = buf2 + PTR_DIFF(req->out.hdr, req->out.buffer);
239 req->out.buffer = buf2;
244 grow the data buffer portion of a reply packet. Note that as this
245 can reallocate the packet buffer this invalidates any local pointers
248 To cope with this req->out.ptr is supplied. This will be updated to
249 point at the same offset into the packet as before this call
251 void req_grow_data(struct smbsrv_request *req, uint_t new_size)
255 if (!(req->control_flags & SMBSRV_REQ_CONTROL_LARGE) && new_size > req_max_data(req)) {
256 smb_panic("reply buffer too large!");
259 req_grow_allocation(req, new_size);
261 delta = new_size - req->out.data_size;
263 req->out.size += delta;
264 req->out.data_size += delta;
266 /* set the BCC to the new data size */
267 SSVAL(req->out.vwv, VWV(req->out.wct), new_size);
271 send a reply and destroy the request buffer
273 note that this only looks at req->out.buffer and req->out.size, allowing manually
274 constructed packets to be sent
276 void smbsrv_send_reply_nosign(struct smbsrv_request *req)
281 if (req->out.size > NBT_HDR_SIZE) {
282 _smb_setlen(req->out.buffer, req->out.size - NBT_HDR_SIZE);
285 blob = data_blob_const(req->out.buffer, req->out.size);
286 status = packet_send(req->smb_conn->packet, blob);
287 if (!NT_STATUS_IS_OK(status)) {
288 smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
294 possibly sign a message then send a reply and destroy the request buffer
296 note that this only looks at req->out.buffer and req->out.size, allowing manually
297 constructed packets to be sent
299 void smbsrv_send_reply(struct smbsrv_request *req)
301 smbsrv_sign_packet(req);
303 smbsrv_send_reply_nosign(req);
307 setup the header of a reply to include an NTSTATUS code
309 void smbsrv_setup_error(struct smbsrv_request *req, NTSTATUS status)
311 if (!req->smb_conn->config.nt_status_support || !(req->smb_conn->negotiate.client_caps & CAP_STATUS32)) {
312 /* convert to DOS error codes */
315 ntstatus_to_dos(status, &eclass, &ecode);
316 SCVAL(req->out.hdr, HDR_RCLS, eclass);
317 SSVAL(req->out.hdr, HDR_ERR, ecode);
318 SSVAL(req->out.hdr, HDR_FLG2, SVAL(req->out.hdr, HDR_FLG2) & ~FLAGS2_32_BIT_ERROR_CODES);
322 if (NT_STATUS_IS_DOS(status)) {
323 /* its a encoded DOS error, using the reserved range */
324 SSVAL(req->out.hdr, HDR_RCLS, NT_STATUS_DOS_CLASS(status));
325 SSVAL(req->out.hdr, HDR_ERR, NT_STATUS_DOS_CODE(status));
326 SSVAL(req->out.hdr, HDR_FLG2, SVAL(req->out.hdr, HDR_FLG2) & ~FLAGS2_32_BIT_ERROR_CODES);
328 SIVAL(req->out.hdr, HDR_RCLS, NT_STATUS_V(status));
329 SSVAL(req->out.hdr, HDR_FLG2, SVAL(req->out.hdr, HDR_FLG2) | FLAGS2_32_BIT_ERROR_CODES);
334 construct and send an error packet, then destroy the request
335 auto-converts to DOS error format when appropriate
337 void smbsrv_send_error(struct smbsrv_request *req, NTSTATUS status)
339 if (req->smb_conn->connection->event.fde == NULL) {
340 /* the socket has been destroyed - no point trying to send an error! */
344 smbsrv_setup_reply(req, 0, 0);
346 /* error returns never have any data */
347 req_grow_data(req, 0);
349 smbsrv_setup_error(req, status);
350 smbsrv_send_reply(req);
355 push a string into the data portion of the request packet, growing it if necessary
356 this gets quite tricky - please be very careful to cover all cases when modifying this
358 if dest is NULL, then put the string at the end of the data portion of the packet
360 if dest_len is -1 then no limit applies
362 size_t req_push_str(struct smbsrv_request *req, uint8_t *dest, const char *str, int dest_len, uint_t flags)
367 const int max_bytes_per_char = 3;
369 if (!(flags & (STR_ASCII|STR_UNICODE))) {
370 flags |= (req->flags2 & FLAGS2_UNICODE_STRINGS) ? STR_UNICODE : STR_ASCII;
374 dest = req->out.data + req->out.data_size;
377 if (dest_len != -1) {
380 len = (strlen(str)+2) * max_bytes_per_char;
383 grow_size = len + PTR_DIFF(dest, req->out.data);
384 buf0 = req->out.buffer;
386 req_grow_allocation(req, grow_size);
388 if (buf0 != req->out.buffer) {
389 dest = req->out.buffer + PTR_DIFF(dest, buf0);
392 len = push_string(dest, str, len, flags);
394 grow_size = len + PTR_DIFF(dest, req->out.data);
396 if (grow_size > req->out.data_size) {
397 req_grow_data(req, grow_size);
404 append raw bytes into the data portion of the request packet
405 return the number of bytes added
407 size_t req_append_bytes(struct smbsrv_request *req,
408 const uint8_t *bytes, size_t byte_len)
410 req_grow_allocation(req, byte_len + req->out.data_size);
411 memcpy(req->out.data + req->out.data_size, bytes, byte_len);
412 req_grow_data(req, byte_len + req->out.data_size);
416 append variable block (type 5 buffer) into the data portion of the request packet
417 return the number of bytes added
419 size_t req_append_var_block(struct smbsrv_request *req,
420 const uint8_t *bytes, uint16_t byte_len)
422 req_grow_allocation(req, byte_len + 3 + req->out.data_size);
423 SCVAL(req->out.data + req->out.data_size, 0, 5);
424 SSVAL(req->out.data + req->out.data_size, 1, byte_len); /* add field length */
426 memcpy(req->out.data + req->out.data_size + 3, bytes, byte_len);
428 req_grow_data(req, byte_len + 3 + req->out.data_size);
432 pull a UCS2 string from a request packet, returning a talloced unix string
434 the string length is limited by the 3 things:
435 - the data size in the request (end of packet)
436 - the passed 'byte_len' if it is not -1
437 - the end of string (null termination)
439 Note that 'byte_len' is the number of bytes in the packet
441 on failure zero is returned and *dest is set to NULL, otherwise the number
442 of bytes consumed in the packet is returned
444 static size_t req_pull_ucs2(struct smbsrv_request *req, const char **dest, const uint8_t *src, int byte_len, uint_t flags)
446 int src_len, src_len2, alignment=0;
450 if (!(flags & STR_NOALIGN) && ucs2_align(req->in.buffer, src, flags)) {
453 if (byte_len != -1) {
458 if (flags & STR_NO_RANGE_CHECK) {
461 src_len = req->in.data_size - PTR_DIFF(src, req->in.data);
462 if (byte_len != -1 && src_len > byte_len) {
472 src_len2 = utf16_len_n(src, src_len);
474 *dest = talloc_strdup(req, "");
475 return src_len2 + alignment;
478 ret = convert_string_talloc(req, CH_UTF16, CH_UNIX, src, src_len2, (void **)&dest2);
486 return src_len2 + alignment;
490 pull a ascii string from a request packet, returning a talloced string
492 the string length is limited by the 3 things:
493 - the data size in the request (end of packet)
494 - the passed 'byte_len' if it is not -1
495 - the end of string (null termination)
497 Note that 'byte_len' is the number of bytes in the packet
499 on failure zero is returned and *dest is set to NULL, otherwise the number
500 of bytes consumed in the packet is returned
502 static size_t req_pull_ascii(struct smbsrv_request *req, const char **dest, const uint8_t *src, int byte_len, uint_t flags)
504 int src_len, src_len2;
508 if (flags & STR_NO_RANGE_CHECK) {
511 src_len = req->in.data_size - PTR_DIFF(src, req->in.data);
516 if (byte_len != -1 && src_len > byte_len) {
521 src_len2 = strnlen((const char *)src, src_len);
522 if (src_len2 <= src_len - 1) {
523 /* include the termination if we didn't reach the end of the packet */
527 ret = convert_string_talloc(req, CH_DOS, CH_UNIX, src, src_len2, (void **)&dest2);
539 pull a string from a request packet, returning a talloced string
541 the string length is limited by the 3 things:
542 - the data size in the request (end of packet)
543 - the passed 'byte_len' if it is not -1
544 - the end of string (null termination)
546 Note that 'byte_len' is the number of bytes in the packet
548 on failure zero is returned and *dest is set to NULL, otherwise the number
549 of bytes consumed in the packet is returned
551 size_t req_pull_string(struct smbsrv_request *req, const char **dest, const uint8_t *src, int byte_len, uint_t flags)
553 if (!(flags & STR_ASCII) &&
554 (((flags & STR_UNICODE) || (req->flags2 & FLAGS2_UNICODE_STRINGS)))) {
555 return req_pull_ucs2(req, dest, src, byte_len, flags);
558 return req_pull_ascii(req, dest, src, byte_len, flags);
563 pull a ASCII4 string buffer from a request packet, returning a talloced string
565 an ASCII4 buffer is a null terminated string that has a prefix
566 of the character 0x4. It tends to be used in older parts of the protocol.
568 on failure *dest is set to the zero length string. This seems to
569 match win2000 behaviour
571 size_t req_pull_ascii4(struct smbsrv_request *req, const char **dest, const uint8_t *src, uint_t flags)
575 if (PTR_DIFF(src, req->in.data) + 1 > req->in.data_size) {
576 /* win2000 treats this as the empty string! */
577 (*dest) = talloc_strdup(req, "");
581 /* this consumes the 0x4 byte. We don't check whether the byte
582 is actually 0x4 or not. This matches win2000 server
586 ret = req_pull_string(req, dest, src, -1, flags);
588 (*dest) = talloc_strdup(req, "");
596 pull a DATA_BLOB from a request packet, returning a talloced blob
598 return False if any part is outside the data portion of the packet
600 BOOL req_pull_blob(struct smbsrv_request *req, const uint8_t *src, int len, DATA_BLOB *blob)
602 if (len != 0 && req_data_oob(req, src, len)) {
606 (*blob) = data_blob_talloc(req, src, len);
611 /* check that a lump of data in a request is within the bounds of the data section of
613 BOOL req_data_oob(struct smbsrv_request *req, const uint8_t *ptr, uint32_t count)
619 /* be careful with wraparound! */
620 if (ptr < req->in.data ||
621 ptr >= req->in.data + req->in.data_size ||
622 count > req->in.data_size ||
623 ptr + count > req->in.data + req->in.data_size) {
631 pull an open file handle from a packet, taking account of the chained_fnum
633 uint16_t req_fnum(struct smbsrv_request *req, const uint8_t *base, uint_t offset)
635 if (req->chained_fnum != -1) {
636 return req->chained_fnum;
638 return SVAL(base, offset);