Mercurial > dropbear

annotate src/pk/pkcs1/pkcs_1_oaep_encode.c @ 280:59400faa4b44 libtomcrypt-orig libtomcrypt-1.05

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Re-import libtomcrypt 1.05 for cleaner propagating. From crypt-1.05.tar.bz2, SHA1 of 88250202bb51570dc64f7e8f1c943cda9479258f
author Matt Johnston <matt@ucc.asn.au>
date Wed, 08 Mar 2006 12:58:00 +0000
parents
children d5faf4814ddb
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
280
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
2 *
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
3 * LibTomCrypt is a library that provides various cryptographic
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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4 * algorithms in a highly modular and flexible manner.
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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5 *
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
6 * The library is free for all purposes without any express
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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7 * guarantee it works.
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
8 *
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
9 * Tom St Denis, [email protected], http://libtomcrypt.org
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
10 */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
11 #include "tomcrypt.h"
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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12
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
13 /**
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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14 @file pkcs_1_oaep_encode.c
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
15 OAEP Padding for PKCS #1, Tom St Denis
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
16 */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
17
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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18 #ifdef PKCS_1
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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19
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
20 /**
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
21 PKCS #1 v2.00 OAEP encode
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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22 @param msg The data to encode
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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23 @param msglen The length of the data to encode (octets)
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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24 @param lparam A session or system parameter (can be NULL)
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
25 @param lparamlen The length of the lparam data
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
26 @param modulus_bitlen The bit length of the RSA modulus
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
27 @param prng An active PRNG state
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
28 @param prng_idx The index of the PRNG desired
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
29 @param hash_idx The index of the hash desired
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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30 @param out [out] The destination for the encoded data
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
31 @param outlen [in/out] The max size and resulting size of the encoded data
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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32 @return CRYPT_OK if successful
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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33 */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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34 int pkcs_1_oaep_encode(const unsigned char *msg, unsigned long msglen,
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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35 const unsigned char *lparam, unsigned long lparamlen,
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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36 unsigned long modulus_bitlen, prng_state *prng,
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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37 int prng_idx, int hash_idx,
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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38 unsigned char *out, unsigned long *outlen)
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
39 {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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40 unsigned char *DB, *seed, *mask;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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41 unsigned long hLen, x, y, modulus_len;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
42 int err;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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43
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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44 LTC_ARGCHK(msg != NULL);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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45 LTC_ARGCHK(out != NULL);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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46 LTC_ARGCHK(outlen != NULL);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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47
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
48 /* test valid hash */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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49 if ((err = hash_is_valid(hash_idx)) != CRYPT_OK) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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50 return err;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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51 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
52
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
53 /* valid prng */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
54 if ((err = prng_is_valid(prng_idx)) != CRYPT_OK) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
55 return err;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
56 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
57
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
58 hLen = hash_descriptor[hash_idx].hashsize;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
59 modulus_len = (modulus_bitlen >> 3) + (modulus_bitlen & 7 ? 1 : 0);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
60
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
61 /* test message size */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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62 if ((2*hLen >= (modulus_len - 2)) || (msglen > (modulus_len - 2*hLen - 2))) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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63 return CRYPT_PK_INVALID_SIZE;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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64 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
65
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
66 /* allocate ram for DB/mask/salt of size modulus_len */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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67 DB = XMALLOC(modulus_len);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
68 mask = XMALLOC(modulus_len);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
69 seed = XMALLOC(hLen);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
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diff changeset
70 if (DB == NULL || mask == NULL || seed == NULL) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
71 if (DB != NULL) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
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72 XFREE(DB);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
73 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
74 if (mask != NULL) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
75 XFREE(mask);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
76 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
77 if (seed != NULL) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
78 XFREE(seed);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
79 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
80 return CRYPT_MEM;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
81 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
82
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
83 /* get lhash */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
84 /* DB == lhash || PS || 0x01 || M, PS == k - mlen - 2hlen - 2 zeroes */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
85 x = modulus_len;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
86 if (lparam != NULL) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
87 if ((err = hash_memory(hash_idx, lparam, lparamlen, DB, &x)) != CRYPT_OK) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
88 goto LBL_ERR;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
89 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
90 } else {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
91 /* can't pass hash_memory a NULL so use DB with zero length */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
92 if ((err = hash_memory(hash_idx, DB, 0, DB, &x)) != CRYPT_OK) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
93 goto LBL_ERR;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
94 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
95 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
96
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
97 /* append PS then 0x01 (to lhash) */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
98 x = hLen;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
99 y = modulus_len - msglen - 2*hLen - 2;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
100 XMEMSET(DB+x, 0, y);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
101 x += y;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
102
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
103 /* 0x01 byte */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
104 DB[x++] = 0x01;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
105
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
106 /* message (length = msglen) */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
107 XMEMCPY(DB+x, msg, msglen);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
108 x += msglen;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
109
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
110 /* now choose a random seed */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
111 if (prng_descriptor[prng_idx].read(seed, hLen, prng) != hLen) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
112 err = CRYPT_ERROR_READPRNG;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
113 goto LBL_ERR;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
114 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
115
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
116 /* compute MGF1 of seed (k - hlen - 1) */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
117 if ((err = pkcs_1_mgf1(seed, hLen, hash_idx, mask, modulus_len - hLen - 1)) != CRYPT_OK) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
118 goto LBL_ERR;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
119 }
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Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
120
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
121 /* xor against DB */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
122 for (y = 0; y < (modulus_len - hLen - 1); y++) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
123 DB[y] ^= mask[y];
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
124 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
125
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Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
126 /* compute MGF1 of maskedDB (hLen) */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
127 if ((err = pkcs_1_mgf1(DB, modulus_len - hLen - 1, hash_idx, mask, hLen)) != CRYPT_OK) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
128 goto LBL_ERR;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
129 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
130
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
131 /* XOR against seed */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
132 for (y = 0; y < hLen; y++) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
133 seed[y] ^= mask[y];
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
134 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
135
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
136 /* create string of length modulus_len */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
137 if (*outlen < modulus_len) {
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
138 err = CRYPT_BUFFER_OVERFLOW;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
139 goto LBL_ERR;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
140 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
141
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
142 /* start output which is 0x00 || maskedSeed || maskedDB */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
143 x = 0;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
144 out[x++] = 0x00;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
145 XMEMCPY(out+x, seed, hLen);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
146 x += hLen;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
147 XMEMCPY(out+x, DB, modulus_len - hLen - 1);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
148 x += modulus_len - hLen - 1;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
149
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
150 *outlen = x;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
151
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
152 err = CRYPT_OK;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
153 LBL_ERR:
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
154 #ifdef LTC_CLEAN_STACK
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
155 zeromem(DB, modulus_len);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
156 zeromem(seed, hLen);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
157 zeromem(mask, modulus_len);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
158 #endif
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
159
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
160 XFREE(seed);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
161 XFREE(mask);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
162 XFREE(DB);
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
163
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
164 return err;
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
165 }
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
166
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
167 #endif /* PKCS_1 */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
168
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
169
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
170 /* $Source: /cvs/libtom/libtomcrypt/src/pk/pkcs1/pkcs_1_oaep_encode.c,v $ */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
171 /* $Revision: 1.4 $ */
59400faa4b44 Re-import libtomcrypt 1.05 for cleaner propagating.
Matt Johnston <matt@ucc.asn.au>
parents:
diff changeset
172 /* $Date: 2005/05/05 14:35:59 $ */