5 * (c) 2000 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 ------------------------------------------------------*/
32 #include <mLib/bits.h>
33 #include <mLib/dstr.h>
39 /*----- Main code ---------------------------------------------------------*/
41 /* --- @pkcs1_cryptencode@ --- *
43 * Arguments: @mp *d@ = where to put the answer
44 * @const void *m@ = pointer to message data
45 * @size_t msz@ = size of message data
46 * @octet *b@ = spare buffer
47 * @size_t sz@ = size of the buffer (big enough)
48 * @unsigned long nbits@ = length of bits of @n@
49 * @void *p@ = pointer to PKCS1 parameter block
51 * Returns: The encoded result, or null.
53 * Use: Implements the operation @EME-PKCS1-V1_5-ENCODE@, as defined
54 * in PKCS#1 v. 2.0 (RFC2437).
57 mp *pkcs1_cryptencode(mp *d, const void *m, size_t msz, octet *b, size_t sz,
58 unsigned long nbits, void *p)
65 /* --- Ensure that the buffer is sensibly sized --- */
67 if (pp->epsz + msz + 11 > sz)
70 /* --- Allocate the buffer and fill it in --- */
75 n = sz - msz - pp->epsz - 3;
77 for (i = 0; i < n; i++) {
79 *q = r->ops->range(r, 255) + 1;
84 memcpy(q, pp->ep, pp->epsz);
91 /* --- Collect the result --- */
93 return (mp_loadb(d, b, sz));
96 /* --- @pkcs1_cryptdecode@ --- *
98 * Arguments: @mp *m@ = the decrypted message
99 * @octet *b@ = pointer to a buffer to work in
100 * @size_t sz@ = the size of the buffer (big enough)
101 * @unsigned long nbits@ = the number of bits in @n@
102 * @void *p@ = pointer to PKCS1 parameter block
104 * Returns: The length of the output string if successful, negative on
107 * Use: Implements the operation @EME-PKCS1-V1_5-DECODE@, as defined
108 * in PKCS#1 v. 2.0 (RFC2437).
111 int pkcs1_cryptdecode(mp *m, octet *b, size_t sz,
112 unsigned long nbits, void *p)
119 /* --- Check the size of the block looks sane --- */
121 if (pp->epsz + 11 > sz) /* OK: independent of ciphertext */
127 /* --- Ensure that the block looks OK --- */
129 goodp &= ct_inteq(*q++, 0);
130 goodp &= ct_inteq(*q++, 2);
132 /* --- Check the nonzero padding --- */
135 while (*q != 0 && q < qq)
137 goodp &= ct_intle(8, i);
138 goodp &= ~ct_intle(qq - q, pp->epsz + 1);
141 /* --- Check the encoding parameters --- */
144 goodp &= ct_memeq(b + ct_pick(goodp, 0, q - b), pp->ep, pp->epsz);
150 memmove(b, b + ct_pick(goodp, 1, q - b), n);
151 return (goodp ? n : -1);
154 /* --- @pkcs1_sigencode@ --- *
156 * Arguments: @mp *d@ = where to put the answer
157 * @const void *m@ = pointer to message data
158 * @size_t msz@ = size of message data
159 * @octet *b@ = spare buffer
160 * @size_t sz@ = size of the buffer (big enough)
161 * @unsigned long nbits@ = length of bits of @n@
162 * @void *p@ = pointer to PKCS1 parameter block
164 * Returns: The encoded message representative, or null.
166 * Use: Implements the operation @EMSA-PKCS1-V1_5-ENCODE@, as defined
167 * in PKCS#1 v. 2.0 (RFC2437).
170 mp *pkcs1_sigencode(mp *d, const void *m, size_t msz, octet *b, size_t sz,
171 unsigned long nbits, void *p)
177 /* --- Ensure that the buffer is sensibly sized --- */
179 if (pp->epsz + msz + 11 > sz)
182 /* --- Fill in the buffer --- */
187 n = sz - msz - pp->epsz - 3;
192 memcpy(q, pp->ep, pp->epsz);
198 return (mp_loadb(d, b, sz));
201 /* --- @pkcs1_sigdecode@ --- *
203 * Arguments: @mp *s@ = the message representative
204 * @const void *m@ = the original message, or null (ignored)
205 * @size_t msz@ = the message size (ignored)
206 * @octet *b@ = a scratch buffer
207 * @size_t sz@ = size of the buffer (large enough)
208 * @unsigned long nbits@ = number of bits in @n@
209 * @void *p@ = pointer to PKCS1 parameters
211 * Returns: The length of the output string if successful, negative on
214 * Use: Implements the operation @EMSA-PKCS1-V1_5-DECODE@, as defined
215 * in PKCS#1 v. 2.0 (RFC2437).
218 int pkcs1_sigdecode(mp *s, const void *m, size_t msz, octet *b, size_t sz,
219 unsigned long nbits, void *p)
225 /* --- Check the size of the block looks sane --- */
227 if (pp->epsz + 10 > sz)
233 /* --- Ensure that the block looks OK --- */
235 if (*q++ != 0x00 || *q++ != 0x01)
238 /* --- Check the padding --- */
241 while (*q == 0xff && q < qq)
243 if (i < 8 || qq - q < pp->epsz + 1 || *q++ != 0)
246 /* --- Check the encoding parameters --- */
248 if (pp->ep && memcmp(q, pp->ep, pp->epsz) != 0)
259 /*----- That's all, folks -------------------------------------------------*/