+++ /dev/null
-/* -*-c-*-
- *
- * $Id$
- *
- * Key textual 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 <ctype.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <mLib/base64.h>
-#include <mLib/bits.h>
-#include <mLib/dstr.h>
-#include <mLib/sub.h>
-#include <mLib/sym.h>
-#include <mLib/url.h>
-
-#include "key-data.h"
-#include "mp.h"
-#include "mptext.h"
-
-/*----- Main code ---------------------------------------------------------*/
-
-/* --- @key_read@ --- *
- *
- * Arguments: @const char *p@ = pointer to textual key representation
- * @char **pp@ = where to store the end pointer
- *
- * Returns: The newly-read key data, or null if it failed.
- *
- * Use: Parses a textual key description.
- */
-
-key_data *key_read(const char *p, char **pp)
-{
- unsigned e;
- key_data *kd;
-
- /* --- Read the encoding type --- *
- *
- * The key format is `[FLAGS:]DATA'. If there is no encoding type
- * named, assume that it's `binary' for backwards compatibility.
- */
-
- if (strchr(p, ':') == 0)
- e = 0;
- else {
- char *q;
- if (key_readflags(p, &q, &e, 0))
- return (0);
- p = q + 1;
- }
-
- /* --- Now scan the data based on the encoding type --- */
-
- switch (e & KF_ENCMASK) {
-
- /* --- Binary encoding --- *
- *
- * Simply read out the Base64-encoded data. Since `,' and `]' are our
- * delimeter characters, and they can't appear in Base64-encoded data, I
- * can just do a simple search to find the end of the encoded data.
- */
-
- case KENC_BINARY:
- case KENC_ENCRYPT: {
- dstr d = DSTR_INIT;
- base64_ctx b;
- size_t sz = strcspn(p, ",]");
-
- base64_init(&b);
- base64_decode(&b, p, sz, &d);
- base64_decode(&b, 0, 0, &d);
- kd = key_newbinary(e, d.buf, d.len);
- dstr_destroy(&d);
- p += sz;
- } break;
-
- /* --- Multiprecision integer encoding --- *
- *
- * Multiprecision integers have a convenient reading function.
- */
-
- case KENC_MP: {
- char *q;
- mp *m = mp_readstring(e & KF_BURN ? MP_NEWSEC : MP_NEW, p, &q, 0);
- if (!m)
- return (0);
- kd = key_newmp(e, m);
- MP_DROP(m);
- p = q;
- } break;
-
- /* --- String encoding --- *
- *
- * We use form-urlencoding to ensure that evil characters don't get out.
- */
-
- case KENC_STRING: {
- dstr d = DSTR_INIT;
- size_t sz = strcspn(p, ",]");
- const char *l = p + sz;
- unsigned int ch;
- int x, n;
-
- while (p < l) {
- switch (*p) {
- case '+':
- DPUTC(&d, ' '); break;
- case '%':
- x = sscanf(p + 1, "%2x%n", &ch, &n);
- if (x == 1) { DPUTC(&d, ch); p += n; break; }
- default:
- DPUTC(&d, *p); break;
- }
- p++;
- }
- DPUTZ(&d);
- kd = key_newstring(e, d.buf);
- dstr_destroy(&d);
- } break;
-
- /* --- Elliptic curve encoding --- *
- *
- * Again, we have a convenient function. Assume for now that points
- * aren't secret. (Reasonably safe.)
- */
-
- case KENC_EC: {
- ec pt = EC_INIT;
- qd_parse qd;
- qd.p = p;
- qd.e = 0;
- if (!ec_ptparse(&qd, &pt))
- return (0);
- kd = key_newec(e, &pt);
- EC_DESTROY(&pt);
- p = qd.p;
- } break;
-
- /* --- Structured information encoding --- *
- *
- * The format for structured key data is `[NAME=KEY,...]', where the
- * brackets are part of the syntax. Structured keys have no flags apart
- * from the encoding.
- *
- * The binary encoding only allows names up to 255 bytes long. Check for
- * this here.
- */
-
- case KENC_STRUCT: {
- dstr d = DSTR_INIT;
- key_data *nkd;
- char *q;
-
- /* --- Read the opening bracket --- */
-
- kd = key_newstruct();
- if (*p != '[')
- return (0);
- p++;
-
- /* --- Read named key subparts --- */
-
- for (;;) {
- size_t sz;
-
- /* --- Stop if there's a close-bracket --- *
- *
- * This allows `[]' to be an empty structured key, which is good. It
- * also makes `[foo=enc:bar,]' legal, and that's less good but I can
- * live with it.
- */
-
- if (*p == ']')
- break;
-
- /* --- Read the name out and check the length --- */
-
- if ((q = strchr(p, '=')) == 0)
- goto fail;
- sz = q - p;
- if (sz >= 256)
- goto fail;
- DRESET(&d);
- DPUTM(&d, p, sz);
- DPUTZ(&d);
-
- /* --- Read the key data for the subkey --- */
-
- if ((nkd = key_read(q + 1, &q)) == 0)
- goto fail;
- key_structsteal(kd, d.buf, nkd);
- p = q;
-
- /* --- Read the comma or close-bracket --- */
-
- if (*p == ']')
- break;
- else if (*p == ',')
- p++;
- else
- goto fail;
- }
-
- /* --- Step past the close bracket --- */
-
- p++;
- dstr_destroy(&d);
- break;
-
- /* --- Tidy up after a failure --- */
-
- fail:
- dstr_destroy(&d);
- return (0);
- } break;
-
- /* --- Anything else is unknown --- */
-
- default:
- return (0);
- }
-
- /* --- Return the end pointer --- */
-
- kd->e = e;
- if (pp)
- *pp = (char *)p;
- return (kd);
-}
-
-/* --- @key_write@ --- *
- *
- * Arguments: @key_data *k@ = pointer to key data
- * @dstr *d@ = destination string to write on
- * @const key_filter *kf@ = pointer to key selection block
- *
- * Returns: Nonzero if an item was actually written.
- *
- * Use: Writes a key in a textual encoding.
- */
-
-int key_write(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: {
- base64_ctx b;
-
- if ((k->e & KF_ENCMASK) == KENC_BINARY)
- key_writeflags(k->e, d);
- else
- DPUTS(d, "encrypt,secret");
- DPUTC(d, ':');
- base64_init(&b);
- b.indent = "";
- b.maxline = 0;
- base64_encode(&b, k->u.k.k, k->u.k.sz, d);
- base64_encode(&b, 0, 0, d);
- rc = 1;
- } break;
- case KENC_MP:
- key_writeflags(k->e, d);
- DPUTC(d, ':');
- mp_writedstr(k->u.m, d, 10);
- rc = 1;
- break;
- case KENC_STRING: {
- const char *p = k->u.p;
- key_writeflags(k->e, d);
- DPUTC(d, ':');
- while (*p) {
- if (*p == ' ') DPUTC(d, '+');
- else if (!isalnum((unsigned char)*p)) dstr_putf(d, "%%%02x", *p);
- else DPUTC(d, *p);
- p++;
- }
- rc = 1;
- } break;
- case KENC_EC:
- key_writeflags(k->e, d);
- DPUTS(d, ":0x"); mp_writedstr(k->u.e.x, d, 16);
- DPUTS(d, ",0x"); mp_writedstr(k->u.e.y, d, 16);
- rc = 1;
- break;
- case KENC_STRUCT: {
- key_subkeyiter i;
- const char *tag;
- char del = 0;
- size_t n = d->len;
-
- DPUTS(d, "struct:[");
- for (key_mksubkeyiter(&i, k); key_nextsubkey(&i, &tag, &k); ) {
- size_t o = d->len;
- if (del)
- DPUTC(d, del);
- DPUTS(d, tag);
- DPUTC(d, '=');
- if (!key_write(k, d, kf))
- d->len = o;
- else {
- del = ',';
- rc = 1;
- }
- }
- if (!rc)
- d->len = n;
- else
- DPUTC(d, ']');
- } break;
- }
- DPUTZ(d);
-
- return (rc);
-}
-
-/*----- That's all, folks -------------------------------------------------*/
projects / u / mdw / catacomb / blobdiff