3 * The SSL pseudo-random function
5 * (c) 2001 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 ------------------------------------------------------*/
30 #include <mLib/alloc.h>
31 #include <mLib/dstr.h>
40 /*----- Main code ---------------------------------------------------------*/
44 * Arguments: @sslprf_ctx *c@ = pointer to context structure
48 * Use: Steps the generator.
51 static void step(sslprf_ctx
*c
)
61 for (sz
= c
->i
++; sz
> 0; sz
-= n
) {
68 GH_HASH(h
, c
->k
, c
->ksz
);
69 GH_HASH(h
, c
->sd
, c
->sdsz
);
73 GH_HASH(hh
, c
->k
, c
->ksz
);
74 GH_HASH(hh
, p
, c
->ihashsz
);
75 c
->p
= GH_DONE(hh
, 0);
82 /* --- @sslprf_init@ --- *
84 * Arguments: @sslprf_ctx *c@ = pointer to a context structure
85 * @const gchash *hco, *hci@ = outer and inner hash functions
86 * @const void *k@ = pointer to secret buffer
87 * @size_t ksz@ = size of the secret
88 * @const void *sd@ = pointer to seed buffer
89 * @size_t sdsz@ = size of the seed
93 * Use: Initializes an SSL generator context.
96 void sslprf_init(sslprf_ctx
*c
, const gchash
*hco
, const gchash
*hci
,
97 const void *k
, size_t ksz
,
98 const void *sd
, size_t sdsz
)
100 c
->co
= hco
; c
->ci
= hci
;
101 c
->ohashsz
= hco
->hashsz
; c
->ihashsz
= hci
->hashsz
;
102 c
->k
= k
; c
->ksz
= ksz
; c
->sd
= sd
; c
->sdsz
= sdsz
;
107 /* --- @sslprf_encrypt@ --- *
109 * Arguments: @sslprf_ctx *c@ = pointer to a context structure
110 * @const void *src@ = pointer to source buffer
111 * @void *dest@ = pointer to destination buffer
112 * @size_t sz@ = size of the buffers
116 * Use: Encrypts data using the SSL pseudo-random function. If the
117 * destination pointer is null, the generator is spun and no
118 * output is produced; if the source pointer is null, raw output
119 * from the generator is written; otherwise, the source data is
120 * XORed with the generator output.
123 void sslprf_encrypt(sslprf_ctx
*c
, const void *src
, void *dest
, size_t sz
)
125 const octet
*s
= src
;
141 for (i
= 0; i
< n
; i
++) d
[i
] = s
[i
] ^ c
->p
[i
];
152 /* --- @sslprf_free@ --- *
154 * Arguments: @sslprf_ctx@ = pointer to a context
158 * Use: Frees resources held in an SSL generator context.
161 void sslprf_free(sslprf_ctx
*c
)
166 /* --- Generic random number generator --- */
168 typedef struct grctx
{
174 static void grdestroy(grand
*r
)
176 grctx
*g
= (grctx
*)r
;
177 xfree((char *)g
->ops
.name
);
178 xfree((octet
*)g
->prf
.sd
);
179 sslprf_free(&g
->prf
);
184 static void seed(grctx
*g
, const void *p
, size_t sz
)
187 xfree((octet
*)g
->prf
.sd
);
188 g
->prf
.sd
= q
= xmalloc(sz
);
193 static int grmisc(grand
*r
, unsigned op
, ...)
195 grctx
*g
= (grctx
*)r
;
204 switch (va_arg(ap
, unsigned)) {
207 case GRAND_SEEDUINT32
:
208 case GRAND_SEEDBLOCK
:
218 i
= va_arg(ap
, unsigned);
220 seed(g
, buf
, sizeof(buf
));
222 case GRAND_SEEDUINT32
:
223 i
= va_arg(ap
, uint32
);
225 seed(g
, buf
, sizeof(buf
));
227 case GRAND_SEEDBLOCK
: {
228 const void *p
= va_arg(ap
, const void *);
229 size_t sz
= va_arg(ap
, size_t);
232 case GRAND_SEEDRAND
: {
233 grand
*rr
= va_arg(ap
, grand
*);
235 rr
->ops
->fill(rr
, buf
, sizeof(buf
));
236 seed(g
, buf
, sizeof(buf
));
247 static octet
grbyte(grand
*r
)
249 grctx
*g
= (grctx
*)r
;
251 sslprf_encrypt(&g
->prf
, 0, &o
, 1);
255 static uint32
grword(grand
*r
)
257 grctx
*g
= (grctx
*)r
;
259 sslprf_encrypt(&g
->prf
, 0, &b
, sizeof(b
));
263 static void grfill(grand
*r
, void *p
, size_t sz
)
265 grctx
*g
= (grctx
*)r
;
266 sslprf_encrypt(&g
->prf
, 0, p
, sz
);
269 static const grand_ops grops
= {
273 grword
, grbyte
, grword
, grand_defaultrange
, grfill
276 /* ---@sslprf_rand@ --- *
278 * Arguments: @const gchash *hco, const gchash *hci@ = hash functions
279 * @const void *k@ = pointer to the key material
280 * @size_t ksz@ = size of the key material
281 * @const void *sd@ = pointer to the seed material
282 * @size_t sdsz@ = size of the seed material
284 * Returns: Pointer to generic random number generator interface.
286 * Use: Creates a generic generator which does TLS data expansion.
289 grand
*sslprf_rand(const gchash
*hco
, const gchash
*hci
,
290 const void *k
, size_t ksz
,
291 const void *sd
, size_t sdsz
)
293 grctx
*g
= S_CREATE(grctx
);
295 octet
*q
= xmalloc(sdsz
);
297 dstr_putf(&d
, "sslprf(%s,%s)", hco
->name
, hci
->name
);
299 g
->ops
.name
= xstrdup(d
.buf
);
302 sslprf_init(&g
->prf
, hco
, hci
, k
, ksz
, q
, sdsz
);
306 /*----- Test rig ----------------------------------------------------------*/
313 #include <mLib/quis.h>
314 #include <mLib/testrig.h>
319 static int v_generate(dstr
*v
)
325 g
= sslprf_rand(&md5
, &sha
, v
[0].buf
, v
[0].len
, v
[1].buf
, v
[1].len
);
326 dstr_ensure(&d
, v
[2].len
);
328 g
->ops
->fill(g
, d
.buf
, d
.len
);
330 if (memcmp(v
[2].buf
, d
.buf
, d
.len
) != 0) {
332 printf("\nfail sslprf:"
334 type_hex
.dump(&v
[0], stdout
);
335 printf("\n\tseed = "); type_hex
.dump(&v
[1], stdout
);
336 printf("\n\texpected = "); type_hex
.dump(&v
[2], stdout
);
337 printf("\n\tcalculated = "); type_hex
.dump(&d
, stdout
);
343 static test_chunk defs
[] = {
344 { "sslprf", v_generate
, { &type_hex
, &type_hex
, &type_hex
, 0 } },
348 int main(int argc
, char *argv
[])
350 test_run(argc
, argv
, defs
, SRCDIR
"/t/sslprf");
356 /*----- That's all, folks -------------------------------------------------*/