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 ------------------------------------------------------*/
34 #include <mLib/base64.h>
35 #include <mLib/bits.h>
36 #include <mLib/dstr.h>
45 /*----- Main code ---------------------------------------------------------*/
47 /* --- @key_read@ --- *
49 * Arguments: @const char *p@ = pointer to textual key representation
50 * @char **pp@ = where to store the end pointer
52 * Returns: The newly-read key data, or null if it failed.
54 * Use: Parses a textual key description.
57 key_data
*key_read(const char *p
, char **pp
)
62 /* --- Read the encoding type --- *
64 * The key format is `[FLAGS:]DATA'. If there is no encoding type
65 * named, assume that it's `binary' for backwards compatibility.
68 if (strchr(p
, ':') == 0)
72 if (key_readflags(p
, &q
, &e
, 0))
77 /* --- Now scan the data based on the encoding type --- */
79 switch (e
& KF_ENCMASK
) {
81 /* --- Binary encoding --- *
83 * Simply read out the Base64-encoded data. Since `,' and `]' are our
84 * delimeter characters, and they can't appear in Base64-encoded data, I
85 * can just do a simple search to find the end of the encoded data.
92 size_t sz
= strcspn(p
, ",]");
95 base64_decode(&b
, p
, sz
, &d
);
96 base64_decode(&b
, 0, 0, &d
);
97 kd
= key_newbinary(e
, d
.buf
, d
.len
);
102 /* --- Multiprecision integer encoding --- *
104 * Multiprecision integers have a convenient reading function.
109 mp
*m
= mp_readstring(e
& KF_BURN ? MP_NEWSEC
: MP_NEW
, p
, &q
, 0);
112 kd
= key_newmp(e
, m
);
117 /* --- String encoding --- *
119 * We use form-urlencoding to ensure that evil characters don't get out.
124 size_t sz
= strcspn(p
, ",]");
125 const char *l
= p
+ sz
;
132 DPUTC(&d
, ' '); break;
134 x
= sscanf(p
+ 1, "%2x%n", &ch
, &n
);
135 if (x
== 1) { DPUTC(&d
, ch
); p
+= n
; break; }
137 DPUTC(&d
, *p
); break;
142 kd
= key_newstring(e
, d
.buf
);
146 /* --- Elliptic curve encoding --- *
148 * Again, we have a convenient function. Assume for now that points
149 * aren't secret. (Reasonably safe.)
157 if (!ec_ptparse(&qd
, &pt
))
159 kd
= key_newec(e
, &pt
);
164 /* --- Structured information encoding --- *
166 * The format for structured key data is `[NAME=KEY,...]', where the
167 * brackets are part of the syntax. Structured keys have no flags apart
170 * The binary encoding only allows names up to 255 bytes long. Check for
179 /* --- Read the opening bracket --- */
181 kd
= key_newstruct();
186 /* --- Read named key subparts --- */
191 /* --- Stop if there's a close-bracket --- *
193 * This allows `[]' to be an empty structured key, which is good. It
194 * also makes `[foo=enc:bar,]' legal, and that's less good but I can
201 /* --- Read the name out and check the length --- */
203 if ((q
= strchr(p
, '=')) == 0)
212 /* --- Read the key data for the subkey --- */
214 if ((nkd
= key_read(q
+ 1, &q
)) == 0)
216 key_structsteal(kd
, d
.buf
, nkd
);
219 /* --- Read the comma or close-bracket --- */
229 /* --- Step past the close bracket --- */
235 /* --- Tidy up after a failure --- */
242 /* --- Anything else is unknown --- */
248 /* --- Return the end pointer --- */
256 /* --- @key_write@ --- *
258 * Arguments: @key_data *k@ = pointer to key data
259 * @dstr *d@ = destination string to write on
260 * @const key_filter *kf@ = pointer to key selection block
262 * Returns: Nonzero if an item was actually written.
264 * Use: Writes a key in a textual encoding.
267 int key_write(key_data
*k
, dstr
*d
, const key_filter
*kf
)
270 if (!KEY_MATCH(k
, kf
))
272 switch (k
->e
& KF_ENCMASK
) {
277 if ((k
->e
& KF_ENCMASK
) == KENC_BINARY
)
278 key_writeflags(k
->e
, d
);
280 DPUTS(d
, "encrypt,secret");
285 base64_encode(&b
, k
->u
.k
.k
, k
->u
.k
.sz
, d
);
286 base64_encode(&b
, 0, 0, d
);
290 key_writeflags(k
->e
, d
);
292 mp_writedstr(k
->u
.m
, d
, 10);
296 const char *p
= k
->u
.p
;
297 key_writeflags(k
->e
, d
);
300 if (*p
== ' ') DPUTC(d
, '+');
301 else if (!isalnum((unsigned char)*p
)) dstr_putf(d
, "%%%02x", *p
);
308 key_writeflags(k
->e
, d
);
309 DPUTS(d
, ":0x"); mp_writedstr(k
->u
.e
.x
, d
, 16);
310 DPUTS(d
, ",0x"); mp_writedstr(k
->u
.e
.y
, d
, 16);
319 DPUTS(d
, "struct:[");
320 for (key_mksubkeyiter(&i
, k
); key_nextsubkey(&i
, &tag
, &k
); ) {
326 if (!key_write(k
, d
, kf
))
344 /*----- That's all, folks -------------------------------------------------*/