3 * $Id: buf.c,v 1.4 2001/06/19 22:09:54 mdw Exp $
7 * (c) 2001 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Trivial IP Encryption (TrIPE).
14 * TrIPE is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * TrIPE 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 General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with TrIPE; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
29 /*----- Revision history --------------------------------------------------*
32 * Revision 1.4 2001/06/19 22:09:54 mdw
33 * Expose interface, for use in the proxy.
35 * Revision 1.3 2001/03/03 12:06:48 mdw
36 * Use 16-bit lengths on MPs, since there's a packet limit of 64K anyway.
38 * Revision 1.2 2001/02/16 21:23:20 mdw
39 * Various minor changes. Check that MPs are in canonical form when
42 * Revision 1.1 2001/02/03 20:26:37 mdw
47 /*----- Header files ------------------------------------------------------*/
51 #include <catacomb/mp.h>
55 /*----- Main code ---------------------------------------------------------*/
57 /* --- @buf_init@ --- *
59 * Arguments: @buf *b@ = pointer to a buffer block
60 * @void *p@ = pointer to a buffer
61 * @size_t sz@ = size of the buffer
65 * Use: Initializes the buffer block appropriately.
68 void buf_init(buf *b, void *p, size_t sz)
75 /* --- @buf_break@ --- *
77 * Arguments: @buf *b@ = pointer to a buffer block
79 * Returns: Some negative value.
81 * Use: Marks a buffer as broken.
84 int buf_break(buf *b) { b->f |= BF_BROKEN; return (-1); }
86 /* --- @buf_flip@ --- *
88 * Arguments: @buf *b@ = pointer to a buffer block
92 * Use: Flips a buffer so that if you've just been writing to it,
93 * you can now read from the bit you've written.
102 /* --- @buf_ensure@ --- *
104 * Arguments: @buf *b@ = pointer to a buffer block
105 * @size_t sz@ = size of data wanted
107 * Returns: Zero if it worked, nonzero if there wasn't enough space.
109 * Use: Ensures that there are @sz@ bytes still in the buffer.
112 int buf_ensure(buf *b, size_t sz) { return (BENSURE(b, sz)); }
114 /* --- @buf_get@ --- *
116 * Arguments: @buf *b@ = pointer to a buffer block
117 * @size_t sz@ = size of the buffer
119 * Returns: Pointer to the place in the buffer.
121 * Use: Reserves a space in the buffer of the requested size, and
122 * returns its start address.
125 void *buf_get(buf *b, size_t sz)
135 /* --- @buf_put@ --- *
137 * Arguments: @buf *b@ = pointer to a buffer block
138 * @const void *p@ = pointer to a buffer
139 * @size_t sz@ = size of the buffer
141 * Returns: Zero if it worked, nonzero if there wasn't enough space.
143 * Use: Fetches data from some place and puts it in the buffer
146 int buf_put(buf *b, const void *p, size_t sz)
150 memcpy(BCUR(b), p, sz);
155 /* --- @buf_getbyte@ --- *
157 * Arguments: @buf *b@ = pointer to a buffer block
159 * Returns: A byte, or less than zero if there wasn't a byte there.
161 * Use: Gets a single byte from a buffer.
164 int buf_getbyte(buf *b)
171 /* --- @buf_putbyte@ --- *
173 * Arguments: @buf *b@ = pointer to a buffer block
174 * @int ch@ = byte to write
176 * Returns: Zero if OK, nonzero if there wasn't enough space.
178 * Use: Puts a single byte in a buffer.
181 int buf_putbyte(buf *b, int ch)
189 /* --- @buf_getu16@ --- *
191 * Arguments: @buf *b@ = pointer to a buffer block
192 * @uint16 *w@ = where to put the word
194 * Returns: Zero if OK, or nonzero if there wasn't a word there.
196 * Use: Gets a 16-bit word from a buffer.
199 int buf_getu16(buf *b, uint16 *w)
208 /* --- @buf_putu16@ --- *
210 * Arguments: @buf *b@ = pointer to a buffer block
211 * @uint16 w@ = word to write
213 * Returns: Zero if OK, nonzero if there wasn't enough space.
215 * Use: Puts a 16-but word in a buffer.
218 int buf_putu16(buf *b, uint16 w)
227 /* --- @buf_getu32@ --- *
229 * Arguments: @buf *b@ = pointer to a buffer block
230 * @uint32 *w@ = where to put the word
232 * Returns: Zero if OK, or nonzero if there wasn't a word there.
234 * Use: Gets a 32-bit word from a buffer.
237 int buf_getu32(buf *b, uint32 *w)
246 /* --- @buf_putu32@ --- *
248 * Arguments: @buf *b@ = pointer to a buffer block
249 * @uint32 w@ = word to write
251 * Returns: Zero if OK, nonzero if there wasn't enough space.
253 * Use: Puts a 32-but word in a buffer.
256 int buf_putu32(buf *b, uint32 w)
265 /* --- @buf_getmp@ --- *
267 * Arguments: @buf *b@ = pointer to a buffer block
269 * Returns: A multiprecision integer, or null if there wasn't one there.
271 * Use: Gets a multiprecision integer from a buffer.
274 mp *buf_getmp(buf *b)
278 if (buf_getu16(b, &sz) || buf_ensure(b, sz))
280 m = mp_loadb(MP_NEW, BCUR(b), sz);
281 if (mp_octets(m) != sz) {
289 /* --- @buf_putmp@ --- *
291 * Arguments: @buf *b@ = pointer to a buffer block
292 * @mp *m@ = a multiprecision integer
294 * Returns: Zero if it worked, nonzero if there wasn't enough space.
296 * Use: Puts a multiprecision integer to a buffer.
299 int buf_putmp(buf *b, mp *m)
301 size_t sz = mp_octets(m);
303 if (buf_putu16(b, sz) || buf_ensure(b, sz))
305 mp_storeb(m, BCUR(b), sz);
310 /*----- That's all, folks -------------------------------------------------*/