5 * Reading and writing packet buffers
7 * (c) 2001 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Catacomb.
14 * Catacomb is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
19 * Catacomb is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
24 * You should have received a copy of the GNU Library General Public
25 * License along with Catacomb; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
30 #ifndef CATACOMB_BUF_H
31 #define CATACOMB_BUF_H
37 /*----- Header files ------------------------------------------------------*/
41 #include <mLib/bits.h>
51 /*----- Data structures ---------------------------------------------------*/
55 * Buffers provide a simple stream-like interface for building and parsing
60 octet
*base
, *p
, *limit
; /* Pointers to the buffer */
61 unsigned f
; /* Various flags */
64 #define BF_BROKEN 1u /* Buffer is broken */
66 /*----- Useful macros -----------------------------------------------------*/
68 #define BBASE(b) ((b)->base)
69 #define BLIM(b) ((b)->limit)
70 #define BCUR(b) ((b)->p)
71 #define BSZ(b) ((b)->limit - (b)->base)
72 #define BLEN(b) ((b)->p - (b)->base)
73 #define BLEFT(b) ((b)->limit - (b)->p)
74 #define BSTEP(b, sz) ((b)->p += (sz))
75 #define BBAD(b) ((b)->f & BF_BROKEN)
76 #define BOK(b) (!BBAD(b))
78 #define BENSURE(b, sz) \
79 (BBAD(b) ? -1 : (sz) > BLEFT(b) ? (b)->f |= BF_BROKEN, -1 : 0)
81 /*----- Functions provided ------------------------------------------------*/
83 /* --- @buf_init@ --- *
85 * Arguments: @buf *b@ = pointer to a buffer block
86 * @void *p@ = pointer to a buffer
87 * @size_t sz@ = size of the buffer
91 * Use: Initializes the buffer block appropriately.
94 extern void buf_init(buf */
*b*/
, void */
*p*/
, size_t /*sz*/);
96 /* --- @buf_break@ --- *
98 * Arguments: @buf *b@ = pointer to a buffer block
100 * Returns: Some negative value.
102 * Use: Marks a buffer as broken.
105 extern int buf_break(buf */
*b*/
);
107 /* --- @buf_flip@ --- *
109 * Arguments: @buf *b@ = pointer to a buffer block
113 * Use: Flips a buffer so that if you've just been writing to it,
114 * you can now read from the bit you've written.
117 extern void buf_flip(buf */
*b*/
);
119 /* --- @buf_ensure@ --- *
121 * Arguments: @buf *b@ = pointer to a buffer block
122 * @size_t sz@ = size of data wanted
124 * Returns: Zero if it worked, nonzero if there wasn't enough space.
126 * Use: Ensures that there are @sz@ bytes still in the buffer.
129 extern int buf_ensure(buf */
*b*/
, size_t /*sz*/);
131 /* --- @buf_get@ --- *
133 * Arguments: @buf *b@ = pointer to a buffer block
134 * @size_t sz@ = size of the buffer
136 * Returns: Pointer to the place in the buffer.
138 * Use: Reserves a space in the buffer of the requested size, and
139 * returns its start address.
142 extern void *buf_get(buf */
*b*/
, size_t /*sz*/);
144 /* --- @buf_put@ --- *
146 * Arguments: @buf *b@ = pointer to a buffer block
147 * @const void *p@ = pointer to a buffer
148 * @size_t sz@ = size of the buffer
150 * Returns: Zero if it worked, nonzero if there wasn't enough space.
152 * Use: Fetches data from some place and puts it in the buffer
155 extern int buf_put(buf */
*b*/
, const void */
*p*/
, size_t /*sz*/);
157 /* --- @buf_getbyte@ --- *
159 * Arguments: @buf *b@ = pointer to a buffer block
161 * Returns: A byte, or less than zero if there wasn't a byte there.
163 * Use: Gets a single byte from a buffer.
166 extern int buf_getbyte(buf */
*b*/
);
168 /* --- @buf_putbyte@ --- *
170 * Arguments: @buf *b@ = pointer to a buffer block
171 * @int ch@ = byte to write
173 * Returns: Zero if OK, nonzero if there wasn't enough space.
175 * Use: Puts a single byte in a buffer.
178 extern int buf_putbyte(buf */
*b*/
, int /*ch*/);
180 /* --- @buf_getu16@ --- *
182 * Arguments: @buf *b@ = pointer to a buffer block
183 * @uint16 *w@ = where to put the word
185 * Returns: Zero if OK, or nonzero if there wasn't a word there.
187 * Use: Gets a 16-bit word from a buffer.
190 extern int buf_getu16(buf */
*b*/
, uint16 */
*w*/
);
192 /* --- @buf_putu16@ --- *
194 * Arguments: @buf *b@ = pointer to a buffer block
195 * @uint16 w@ = word to write
197 * Returns: Zero if OK, nonzero if there wasn't enough space.
199 * Use: Puts a 16-but word in a buffer.
202 extern int buf_putu16(buf */
*b*/
, uint16
/*w*/);
204 /* --- @buf_getu32@ --- *
206 * Arguments: @buf *b@ = pointer to a buffer block
207 * @uint32 *w@ = where to put the word
209 * Returns: Zero if OK, or nonzero if there wasn't a word there.
211 * Use: Gets a 32-bit word from a buffer.
214 extern int buf_getu32(buf */
*b*/
, uint32 */
*w*/
);
216 /* --- @buf_putu32@ --- *
218 * Arguments: @buf *b@ = pointer to a buffer block
219 * @uint32 w@ = word to write
221 * Returns: Zero if OK, nonzero if there wasn't enough space.
223 * Use: Puts a 32-but word in a buffer.
226 extern int buf_putu32(buf */
*b*/
, uint32
/*w*/);
228 /* --- @buf_getmem{8,16,32,z} --- *
230 * Arguments: @buf *b@ = pointer to a buffer block
231 * @size_t *nn@ = where to put the length
233 * Returns: Pointer to the buffer data, or null.
235 * Use: Gets a chunk of memory from a buffer. The number, @16@ or
236 * @32@, is the width of the length; @z@ means null-terminated.
239 extern void *buf_getmem8(buf */
*b*/
, size_t */
*nn*/
);
240 extern void *buf_getmem16(buf */
*b*/
, size_t */
*nn*/
);
241 extern void *buf_getmem32(buf */
*b*/
, size_t */
*nn*/
);
242 extern void *buf_getmemz(buf */
*b*/
, size_t */
*nn*/
);
244 /* --- @buf_putmem{8,16,32,z} --- *
246 * Arguments: @buf *b@ = pointer to a buffer block
247 * @const void *p@ = pointer to data to write
248 * @size_t n@ = length to write
250 * Returns: Zero if OK, nonzero if there wasn't enough space.
252 * Use: Writes a chunk of data to a buffer. The number, @16@ or
253 * @32@, is the width of the length; @z@ means null-terminated.
256 extern int buf_putmem8(buf */
*b*/
, const void */
*p*/
, size_t /*n*/);
257 extern int buf_putmem16(buf */
*b*/
, const void */
*p*/
, size_t /*n*/);
258 extern int buf_putmem32(buf */
*b*/
, const void */
*p*/
, size_t /*n*/);
259 extern int buf_putmemz(buf */
*b*/
, const void */
*p*/
, size_t /*n*/);
261 /* --- @buf_getbuf{8,16,32,z}@ --- *
263 * Arguments: @buf *b@ = pointer to a buffer block
264 * @buf *bb@ = where to put the result
266 * Returns: Zero if it worked, nonzero if there wasn't enough space.
268 * Use: Gets a block of data from a buffer, and writes its bounds to
269 * another buffer. The number, @16@ or @32@, is the width of
270 * the length; @z@ means null-terminated.
273 extern int buf_getbuf8(buf */
*b*/
, buf */
*bb*/
);
274 extern int buf_getbuf16(buf */
*b*/
, buf */
*bb*/
);
275 extern int buf_getbuf32(buf */
*b*/
, buf */
*bb*/
);
276 extern int buf_getbufz(buf */
*b*/
, buf */
*bb*/
);
278 /* --- @buf_putbuf{8,16,32,z}@ --- *
280 * Arguments: @buf *b@ = pointer to a buffer block
281 * @buf *bb@ = buffer to write
283 * Returns: Zero if it worked, nonzero if there wasn't enough space.
285 * Use: Puts the contents of a buffer to a buffer. The number, @16@
286 * or @32@, is the width of the length; @z@ means null-
290 extern int buf_putbuf8(buf */
*b*/
, buf */
*bb*/
);
291 extern int buf_putbuf16(buf */
*b*/
, buf */
*bb*/
);
292 extern int buf_putbuf32(buf */
*b*/
, buf */
*bb*/
);
293 extern int buf_putbufz(buf */
*b*/
, buf */
*bb*/
);
295 /* --- @buf_getstr{8,16,32,z}@ --- *
297 * Arguments: @buf *b@ = pointer to a buffer block
298 * @dstr *d@ = where to put the result
300 * Returns: Zero if it worked, nonzero if there wasn't enough space.
302 * Use: Gets a block of data from a buffer, and writes its contents
303 * to a string. The number, @16@ or @32@, is the width of the
304 * length; @z@ means null-terminated.
307 extern int buf_getstr8(buf */
*b*/
, dstr */
*d*/
);
308 extern int buf_getstr16(buf */
*b*/
, dstr */
*d*/
);
309 extern int buf_getstr32(buf */
*b*/
, dstr */
*d*/
);
310 extern int buf_getstrz(buf */
*b*/
, dstr */
*d*/
);
312 /* --- @buf_putstr{8,16,32,z}@ --- *
314 * Arguments: @buf *b@ = pointer to a buffer block
315 * @dstr *d@ = string to write
317 * Returns: Zero if it worked, nonzero if there wasn't enough space.
319 * Use: Puts a string to a buffer, and writes its bounds to
320 * another buffer. The number, @16@ or @32@, is the width of
321 * the length; @z@ means null-terminated.
324 extern int buf_putstr8(buf */
*b*/
, dstr */
*d*/
);
325 extern int buf_putstr16(buf */
*b*/
, dstr */
*d*/
);
326 extern int buf_putstr32(buf */
*b*/
, dstr */
*d*/
);
327 extern int buf_putstrz(buf */
*b*/
, dstr */
*d*/
);
329 /* --- @buf_getmp@ --- *
331 * Arguments: @buf *b@ = pointer to a buffer block
333 * Returns: A multiprecision integer, or null if there wasn't one there.
335 * Use: Gets a multiprecision integer from a buffer.
338 extern mp
*buf_getmp(buf */
*b*/
);
340 /* --- @buf_putmp@ --- *
342 * Arguments: @buf *b@ = pointer to a buffer block
343 * @mp *m@ = a multiprecision integer
345 * Returns: Zero if it worked, nonzero if there wasn't enough space.
347 * Use: Puts a multiprecision integer to a buffer.
350 extern int buf_putmp(buf */
*b*/
, mp */
*m*/
);
352 /* --- @buf_getec@ --- *
354 * Arguments: @buf *b@ = pointer to a buffer block
355 * @ec *p@ = where to put the point
357 * Returns: Zero if it worked, nonzero if it failed.
359 * Use: Gets a multiprecision integer from a buffer. The point must
363 extern int buf_getec(buf */
*b*/
, ec */
*p*/
);
365 /* --- @buf_putec@ --- *
367 * Arguments: @buf *b@ = pointer to a buffer block
368 * @ec *p@ = an elliptic curve point
370 * Returns: Zero if it worked, nonzero if there wasn't enough space.
372 * Use: Puts an elliptic curve point to a buffer.
375 extern int buf_putec(buf */
*b*/
, ec */
*p*/
);
377 /*----- That's all, folks -------------------------------------------------*/