2 Unix SMB/CIFS implementation.
4 manipulate nbt name structures
6 Copyright (C) Andrew Tridgell 2005
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 see rfc1002 for the detailed format of compressed names
28 #include "system/iconv.h"
29 #include "librpc/gen_ndr/ndr_nbt.h"
31 /* don't allow an unlimited number of name components */
32 #define MAX_COMPONENTS 10
35 pull one component of a compressed name
37 static NTSTATUS ndr_pull_component(struct ndr_pull *ndr, uint8_t **component,
38 uint32_t *offset, uint32_t *max_offset)
43 if (*offset >= ndr->data_size) {
44 return NT_STATUS_BAD_NETWORK_NAME;
46 len = ndr->data[*offset];
49 *max_offset = MAX(*max_offset, *offset);
53 if ((len & 0xC0) == 0xC0) {
54 /* its a label pointer */
55 if (1 + *offset >= ndr->data_size) {
56 return NT_STATUS_BAD_NETWORK_NAME;
58 *max_offset = MAX(*max_offset, *offset + 2);
59 *offset = ((len&0x3F)<<8) | ndr->data[1 + *offset];
60 *max_offset = MAX(*max_offset, *offset);
64 if ((len & 0xC0) != 0) {
65 /* its a reserved length field */
66 return NT_STATUS_BAD_NETWORK_NAME;
68 if (*offset + len + 2 > ndr->data_size) {
69 return NT_STATUS_BAD_NETWORK_NAME;
71 *component = (uint8_t*)talloc_strndup(ndr, &ndr->data[1 + *offset], len);
72 NT_STATUS_HAVE_NO_MEMORY(*component);
74 *max_offset = MAX(*max_offset, *offset);
78 /* too many pointers */
79 return NT_STATUS_BAD_NETWORK_NAME;
83 decompress a 'compressed' name component
85 static NTSTATUS decompress_name(char *name, enum nbt_name_type *type)
88 for (i=0;name[2*i];i++) {
89 uint8_t c1 = name[2*i];
90 uint8_t c2 = name[1+(2*i)];
91 if (c1 < 'A' || c1 > 'P' ||
92 c2 < 'A' || c2 > 'P') {
93 return NT_STATUS_BAD_NETWORK_NAME;
95 name[i] = ((c1-'A')<<4) | (c2-'A');
99 *type = (enum nbt_name_type)(name[15]);
103 *type = NBT_NAME_CLIENT;
106 /* trim trailing spaces */
107 for (;i>0 && name[i-1]==' ';i--) {
116 compress a name component
118 static uint8_t *compress_name(TALLOC_CTX *mem_ctx,
119 const uint8_t *name, enum nbt_name_type type)
125 if (strlen(name) > 15) {
129 cname = talloc_array(mem_ctx, uint8_t, 33);
130 if (cname == NULL) return NULL;
132 for (i=0;name[i];i++) {
133 cname[2*i] = 'A' + (name[i]>>4);
134 cname[1+2*i] = 'A' + (name[i]&0xF);
136 if (strcmp(name, "*") == 0) {
142 cname[2*i] = 'A' + (pad_char>>4);
143 cname[1+2*i] = 'A' + (pad_char&0xF);
147 cname[2*i] = 'A' + (pad_char>>4);
148 cname[1+2*i] = 'A' + (pad_char&0xF);
155 pull a nbt name from the wire
157 NTSTATUS ndr_pull_nbt_name(struct ndr_pull *ndr, int ndr_flags, struct nbt_name *r)
160 uint_t num_components;
161 uint32_t offset = ndr->offset;
162 uint32_t max_offset = offset;
163 uint8_t *components[MAX_COMPONENTS];
167 if (!(ndr_flags & NDR_SCALARS)) {
171 /* break up name into a list of components */
172 for (num_components=0;num_components<MAX_COMPONENTS;num_components++) {
173 status = ndr_pull_component(ndr, &components[num_components],
174 &offset, &max_offset);
175 NT_STATUS_NOT_OK_RETURN(status);
176 if (components[num_components] == NULL) break;
178 if (num_components == MAX_COMPONENTS ||
179 num_components == 0) {
180 return NT_STATUS_BAD_NETWORK_NAME;
183 ndr->offset = max_offset;
185 /* the first component is limited to 16 bytes in the DOS charset,
186 which is 32 in the 'compressed' form */
187 if (strlen(components[0]) > 32) {
188 return NT_STATUS_BAD_NETWORK_NAME;
191 /* decompress the first component */
192 status = decompress_name(components[0], &r->type);
193 NT_STATUS_NOT_OK_RETURN(status);
195 r->name = components[0];
197 /* combine the remaining components into the scope */
198 scope = components[1];
199 for (i=2;i<num_components;i++) {
200 scope = talloc_asprintf_append(scope, ".%s", components[i]);
201 NT_STATUS_HAVE_NO_MEMORY(scope);
210 push a nbt name to the wire
212 NTSTATUS ndr_push_nbt_name(struct ndr_push *ndr, int ndr_flags, struct nbt_name *r)
214 uint_t num_components;
215 uint8_t *components[MAX_COMPONENTS];
216 char *dscope=NULL, *p;
217 uint8_t *cname, *fullname;
221 if (!(ndr_flags & NDR_SCALARS)) {
226 dscope = talloc_strdup(ndr, r->scope);
227 NT_STATUS_HAVE_NO_MEMORY(dscope);
230 cname = compress_name(ndr, r->name, r->type);
231 NT_STATUS_HAVE_NO_MEMORY(cname);
233 /* form the base components */
234 components[0] = cname;
237 while (dscope && (p=strchr(dscope, '.')) &&
238 num_components < MAX_COMPONENTS) {
240 components[num_components] = dscope;
244 if (dscope && num_components < MAX_COMPONENTS) {
245 components[num_components++] = dscope;
247 if (num_components == MAX_COMPONENTS) {
248 return NT_STATUS_BAD_NETWORK_NAME;
251 fullname = talloc_asprintf(ndr, "%c%s", (unsigned char)strlen(cname), cname);
252 NT_STATUS_HAVE_NO_MEMORY(fullname);
254 for (i=1;i<num_components;i++) {
255 fullname = talloc_asprintf_append(fullname, "%c%s",
256 (unsigned char)strlen(components[i]), components[i]);
257 NT_STATUS_HAVE_NO_MEMORY(fullname);
260 /* see if we can find the fullname in the existing packet - if
261 so, we can use a NBT name pointer. This allows us to fit
262 longer names into the packet */
263 fulllen = strlen(fullname)+1;
264 for (i=0;i + fulllen < ndr->offset;i++) {
265 if (ndr->data[i] == fullname[0] &&
266 memcmp(fullname, &ndr->data[i], fulllen) == 0) {
267 talloc_free(fullname);
268 return ndr_push_uint16(ndr, NDR_SCALARS, 0xC000 | i);
272 NDR_CHECK(ndr_push_bytes(ndr, fullname, fulllen));
274 talloc_free(fullname);
281 copy a nbt name structure
283 NTSTATUS nbt_name_dup(TALLOC_CTX *mem_ctx, struct nbt_name *name, struct nbt_name *newname)
286 newname->name = talloc_strdup(mem_ctx, newname->name);
287 NT_STATUS_HAVE_NO_MEMORY(newname->name);
288 newname->scope = talloc_strdup(mem_ctx, newname->scope);
290 NT_STATUS_HAVE_NO_MEMORY(newname->scope);
296 push a nbt name into a blob
298 NTSTATUS nbt_name_to_blob(TALLOC_CTX *mem_ctx, DATA_BLOB *blob, struct nbt_name *name)
300 return ndr_push_struct_blob(blob, mem_ctx, name,
301 (ndr_push_flags_fn_t)ndr_push_nbt_name);
306 pull a nbt name from a blob
308 NTSTATUS nbt_name_from_blob(TALLOC_CTX *mem_ctx, const DATA_BLOB *blob, struct nbt_name *name)
310 return ndr_pull_struct_blob(blob, mem_ctx, name,
311 (ndr_pull_flags_fn_t)ndr_pull_nbt_name);
316 choose a name to use when calling a server in a NBT session request.
317 we use heuristics to see if the name we have been given is a IP
318 address, or a too-long name. If it is then use *SMBSERVER, or a
321 void nbt_choose_called_name(TALLOC_CTX *mem_ctx,
322 struct nbt_name *n, const char *name, int type)
327 if (is_ipaddress(name)) {
328 n->name = "*SMBSERVER";
331 if (strlen(name) > 15) {
332 const char *p = strchr(name, '.');
335 n->name = "*SMBSERVER";
338 s = talloc_strndup(mem_ctx, name, PTR_DIFF(p, name));
339 n->name = strupper_talloc(mem_ctx, s);
343 n->name = strupper_talloc(mem_ctx, name);
348 escape a string into a form containing only a small set of characters,
349 the rest is hex encoded. This is similar to URL encoding
351 static const char *nbt_hex_encode(TALLOC_CTX *mem_ctx, const char *s)
355 const char *valid_chars = "_-.$@ ";
356 #define NBT_CHAR_ALLOW(c) (isalnum(c) || strchr(valid_chars, c))
358 for (len=i=0;s[i];i++,len++) {
359 if (!NBT_CHAR_ALLOW(s[i])) {
364 ret = talloc_array(mem_ctx, char, len+1);
365 if (ret == NULL) return NULL;
367 for (len=i=0;s[i];i++) {
368 if (NBT_CHAR_ALLOW(s[i])) {
371 snprintf(&ret[len], 4, "%%%02x", (unsigned char)s[i]);
382 form a string for a NBT name
384 char *nbt_name_string(TALLOC_CTX *mem_ctx, const struct nbt_name *name)
386 TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
389 ret = talloc_asprintf(mem_ctx, "%s<%02x>-%s",
390 nbt_hex_encode(tmp_ctx, name->name),
392 nbt_hex_encode(tmp_ctx, name->scope));
394 ret = talloc_asprintf(mem_ctx, "%s<%02x>",
395 nbt_hex_encode(tmp_ctx, name->name),
398 talloc_free(tmp_ctx);