5 * (c) 1999 Straylight/Edgeware
8 /*----- Licensing notice --------------------------------------------------*
10 * This file is part of Catacomb.
12 * Catacomb is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU Library General Public License as
14 * published by the Free Software Foundation; either version 2 of the
15 * License, or (at your option) any later version.
17 * Catacomb is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU Library General Public License for more details.
22 * You should have received a copy of the GNU Library General Public
23 * License along with Catacomb; if not, write to the Free
24 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
28 /*----- Header files ------------------------------------------------------*/
33 #include <mLib/bits.h>
34 #include <mLib/dstr.h>
42 /*----- Main code ---------------------------------------------------------*/
44 /* --- @key_decode@ --- *
46 * Arguments: @const void *p@ = pointer to buffer to read
47 * @size_t sz@ = size of the buffer
49 * Returns: The newly-read key data, or null if it failed.
51 * Use: Decodes a binary representation of a key.
54 key_data *key_decode(const void *p, size_t sz)
61 /* --- Parse the header information --- *
63 * Make sure the size matches external reality. Security holes have been
64 * known to creep in without this sort of check. (No, this isn't an after-
73 /* --- Now decide what to do --- */
75 switch (e & KF_ENCMASK) {
77 /* --- Plain binary data --- */
81 kd = key_newbinary(e, q + 4, psz);
84 /* --- Multiprecision integer data --- */
87 kd = key_newmp(e, mp_loadb(e & KF_BURN ? MP_NEWSEC : MP_NEW,
91 /* --- String data --- */
95 kd->u.p = xmalloc(sz + 1);
96 memcpy(kd->u.p, q + 4, sz);
100 /* --- Elliptic curve point data --- */
107 if (sz < 2) return (0);
109 if (sz < xsz + 4) return (0);
110 ysz = LOAD16(q + 6 + xsz);
111 if (sz < xsz + ysz + 4) return (0);
112 kd->u.e.x = mp_loadb(MP_NEW, q + 6, xsz);
113 kd->u.e.y = mp_loadb(MP_NEW, q + 8 + xsz, ysz);
116 /* --- Structured key data --- */
122 if ((e & ~KF_ENCMASK) || (psz & 3))
125 kd = key_newstruct();
129 /* --- Read the tag string --- */
135 DPUTM(&d, q + 1, sz);
140 /* --- Read the encoding and size --- */
142 sz = (LOAD16(q + 2) + 7) & ~3;
146 /* --- Create a table node and fill it in --- */
148 if ((nkd = key_decode(q, sz)) == 0)
150 key_structsteal(kd, d.buf, nkd);
157 /* --- Tidy up after a failure --- */
165 /* --- Everything else --- */
171 /* --- OK, that was good --- */
177 /* --- @key_encode@ --- *
179 * Arguments: @key_data *k@ = pointer to key data block
180 * @dstr *d@ = pointer to destination string
181 * @const key_filter *kf@ = pointer to key selection block
183 * Returns: Nonzero if an item was actually written.
185 * Use: Encodes a key block as binary data.
188 static int ksbyname(const void *a, const void *b) {
189 key_struct *const *x = a, *const *y = b;
190 return (strcmp(SYM_NAME(*x), SYM_NAME(*y)));
193 int key_encode(key_data *k, dstr *d, const key_filter *kf)
196 if (!KEY_MATCH(k, kf))
198 switch (k->e & KF_ENCMASK) {
203 DENSURE(d, (k->u.k.sz + 7) & ~3);
206 STORE16(p + 2, k->u.k.sz);
208 DPUTM(d, k->u.k.k, k->u.k.sz);
214 size_t sz = mp_octets(k->u.m);
216 DENSURE(d, (sz + 7) & ~3);
220 mp_storeb(k->u.m, p + 4, sz);
227 size_t sz = strlen(k->u.p);
229 DENSURE(d, (sz + 7) & ~3);
233 memcpy(p + 4, k->u.p, sz);
240 size_t xsz = 0, ysz = 0;
243 if (EC_ATINF(&k->u.e))
246 xsz = mp_octets(k->u.e.x);
247 ysz = mp_octets(k->u.e.y);
250 DENSURE(d, (sz + 7) & ~3);
254 if (!EC_ATINF(&k->u.e)) {
256 mp_storeb(k->u.e.x, p + 6, xsz);
257 STORE16(p + 6 + xsz, ysz);
258 mp_storeb(k->u.e.y, p + 8 + xsz, ysz);
267 key_struct *ks, **ksv;
274 STORE16(p, k->e & KF_ENCMASK);
277 for (nks = 0, sym_mkiter(&i, &k->u.s);
278 (ks = sym_next(&i)) != 0;
281 ksv = xmalloc(nks * sizeof(*ksv));
282 for (j = 0, sym_mkiter(&i, &k->u.s); (ks = sym_next(&i)) != 0; j++)
284 qsort(ksv, nks, sizeof(*ksv), ksbyname);
285 for (j = 0; j < nks; j++) {
289 *(octet *)(d->buf + d->len++) = strlen(SYM_NAME(ks));
290 DPUTS(d, SYM_NAME(ks));
293 if (key_encode(ks->k, d, kf))
314 /*----- That's all, folks -------------------------------------------------*/