+++ /dev/null
-/* -*-c-*-
- *
- * $Id$
- *
- * Key binary encoding
- *
- * (c) 1999 Straylight/Edgeware
- */
-
-/*----- Licensing notice --------------------------------------------------*
- *
- * This file is part of Catacomb.
- *
- * Catacomb is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Library General Public License as
- * published by the Free Software Foundation; either version 2 of the
- * License, or (at your option) any later version.
- *
- * Catacomb is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with Catacomb; if not, write to the Free
- * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
- * MA 02111-1307, USA.
- */
-
-/*----- Header files ------------------------------------------------------*/
-
-#include <stdlib.h>
-#include <string.h>
-
-#include <mLib/bits.h>
-#include <mLib/dstr.h>
-#include <mLib/sub.h>
-#include <mLib/sym.h>
-
-#include "key-data.h"
-#include "mp.h"
-#include "mptext.h"
-
-/*----- Main code ---------------------------------------------------------*/
-
-/* --- @key_decode@ --- *
- *
- * Arguments: @const void *p@ = pointer to buffer to read
- * @size_t sz@ = size of the buffer
- *
- * Returns: The newly-read key data, or null if it failed.
- *
- * Use: Decodes a binary representation of a key.
- */
-
-key_data *key_decode(const void *p, size_t sz)
-{
- const octet *q = p;
- size_t psz;
- key_data *kd;
- unsigned e;
-
- /* --- Parse the header information --- *
- *
- * Make sure the size matches external reality. Security holes have been
- * known to creep in without this sort of check. (No, this isn't an after-
- * the-fact patch-up.)
- */
-
- e = LOAD16(q);
- psz = LOAD16(q + 2);
- if (psz + 4 > sz)
- return (0);
-
- /* --- Now decide what to do --- */
-
- switch (e & KF_ENCMASK) {
-
- /* --- Plain binary data --- */
-
- case KENC_BINARY:
- case KENC_ENCRYPT:
- kd = key_newbinary(e, q + 4, psz);
- break;
-
- /* --- Multiprecision integer data --- */
-
- case KENC_MP:
- kd = key_newmp(e, mp_loadb(e & KF_BURN ? MP_NEWSEC : MP_NEW,
- q + 4, psz));
- break;
-
- /* --- String data --- */
-
- case KENC_STRING:
- kd = key_newraw(e);
- kd->u.p = xmalloc(sz + 1);
- memcpy(kd->u.p, q + 4, sz);
- kd->u.p[sz] = 0;
- break;
-
- /* --- Elliptic curve point data --- */
-
- case KENC_EC: {
- size_t xsz, ysz;
- kd = key_newraw(e);
- EC_CREATE(&kd->u.e);
- if (!sz) break;
- if (sz < 2) return (0);
- xsz = LOAD16(q + 4);
- if (sz < xsz + 4) return (0);
- ysz = LOAD16(q + 6 + xsz);
- if (sz < xsz + ysz + 4) return (0);
- kd->u.e.x = mp_loadb(MP_NEW, q + 6, xsz);
- kd->u.e.y = mp_loadb(MP_NEW, q + 8 + xsz, ysz);
- } break;
-
- /* --- Structured key data --- */
-
- case KENC_STRUCT: {
- dstr d = DSTR_INIT;
- key_data *nkd;
-
- if ((e & ~KF_ENCMASK) || (psz & 3))
- return (0);
- q += 4;
- kd = key_newstruct();
-
- while (psz) {
-
- /* --- Read the tag string --- */
-
- DRESET(&d);
- sz = LOAD8(q);
- if (sz >= psz)
- goto fail;
- DPUTM(&d, q + 1, sz);
- DPUTZ(&d);
- sz = (sz + 4) & ~3;
- q += sz; psz -= sz;
-
- /* --- Read the encoding and size --- */
-
- sz = (LOAD16(q + 2) + 7) & ~3;
- if (sz > psz)
- goto fail;
-
- /* --- Create a table node and fill it in --- */
-
- if ((nkd = key_decode(q, sz)) == 0)
- goto fail;
- key_structsteal(kd, d.buf, nkd);
- psz -= sz;
- q += sz;
- }
- dstr_destroy(&d);
- break;
-
- /* --- Tidy up after a failure --- */
-
- fail:
- dstr_destroy(&d);
- key_drop(kd);
- return (0);
- } break;
-
- /* --- Everything else --- */
-
- default:
- return (0);
- }
-
- /* --- OK, that was good --- */
-
- kd->e = e;
- return (kd);
-}
-
-/* --- @key_encode@ --- *
- *
- * Arguments: @key_data *k@ = pointer to key data block
- * @dstr *d@ = pointer to destination string
- * @const key_filter *kf@ = pointer to key selection block
- *
- * Returns: Nonzero if an item was actually written.
- *
- * Use: Encodes a key block as binary data.
- */
-
-static int ksbyname(const void *a, const void *b) {
- key_struct *const *x = a, *const *y = b;
- return (strcmp(SYM_NAME(*x), SYM_NAME(*y)));
-}
-
-int key_encode(key_data *k, dstr *d, const key_filter *kf)
-{
- int rc = 0;
- if (!KEY_MATCH(k, kf))
- return (0);
- switch (k->e & KF_ENCMASK) {
- case KENC_BINARY:
- case KENC_ENCRYPT: {
- char *p;
-
- DENSURE(d, (k->u.k.sz + 7) & ~3);
- p = d->buf + d->len;
- STORE16(p, k->e);
- STORE16(p + 2, k->u.k.sz);
- d->len += 4;
- DPUTM(d, k->u.k.k, k->u.k.sz);
- rc = 1;
- } break;
-
- case KENC_MP: {
- char *p;
- size_t sz = mp_octets(k->u.m);
-
- DENSURE(d, (sz + 7) & ~3);
- p = d->buf + d->len;
- STORE16(p, k->e);
- STORE16(p + 2, sz);
- mp_storeb(k->u.m, p + 4, sz);
- d->len += sz + 4;
- rc = 1;
- } break;
-
- case KENC_STRING: {
- char *p;
- size_t sz = strlen(k->u.p);
-
- DENSURE(d, (sz + 7) & ~3);
- p = d->buf + d->len;
- STORE16(p, k->e);
- STORE16(p + 2, sz);
- memcpy(p + 4, k->u.p, sz);
- d->len += sz + 4;
- rc = 1;
- } break;
-
- case KENC_EC: {
- char *p;
- size_t xsz = 0, ysz = 0;
- size_t sz;
-
- if (EC_ATINF(&k->u.e))
- sz = 0;
- else {
- xsz = mp_octets(k->u.e.x);
- ysz = mp_octets(k->u.e.y);
- sz = xsz + ysz + 4;
- }
- DENSURE(d, (sz + 7) & ~3);
- p = d->buf + d->len;
- STORE16(p, k->e);
- STORE16(p + 2, sz);
- if (!EC_ATINF(&k->u.e)) {
- STORE16(p + 4, xsz);
- mp_storeb(k->u.e.x, p + 6, xsz);
- STORE16(p + 6 + xsz, ysz);
- mp_storeb(k->u.e.y, p + 8 + xsz, ysz);
- }
- d->len += sz + 4;
- rc = 1;
- } break;
-
- case KENC_STRUCT: {
- size_t n;
- char *p;
- key_struct *ks, **ksv;
- size_t nks, j;
- sym_iter i;
-
- n = d->len;
- DENSURE(d, 4);
- p = d->buf + n;
- STORE16(p, k->e & KF_ENCMASK);
- d->len += 4;
-
- for (nks = 0, sym_mkiter(&i, &k->u.s);
- (ks = sym_next(&i)) != 0;
- nks++);
- if (nks) {
- ksv = xmalloc(nks * sizeof(*ksv));
- for (j = 0, sym_mkiter(&i, &k->u.s); (ks = sym_next(&i)) != 0; j++)
- ksv[j] = ks;
- qsort(ksv, nks, sizeof(*ksv), ksbyname);
- for (j = 0; j < nks; j++) {
- size_t o = d->len;
- ks = ksv[j];
- DENSURE(d, 1);
- *(octet *)(d->buf + d->len++) = strlen(SYM_NAME(ks));
- DPUTS(d, SYM_NAME(ks));
- while (d->len & 3)
- DPUTC(d, 0);
- if (key_encode(ks->k, d, kf))
- rc = 1;
- else
- d->len = o;
- }
- xfree(ksv);
- }
- if (!rc)
- d->len = n;
- else {
- p = d->buf + n + 2;
- n = d->len - n - 4;
- STORE16(p, n);
- }
- } break;
- }
- while (d->len & 3)
- DPUTC(d, 0);
- return (rc);
-}
-
-/*----- That's all, folks -------------------------------------------------*/
~mdw / catacomb / blobdiff