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authorBob Beck <beck@cvs.openbsd.org>1999-09-29 04:37:45 +0000
committerBob Beck <beck@cvs.openbsd.org>1999-09-29 04:37:45 +0000
commit30902ef04e4a800063b5f4afdbf1732ad34aa6b3 (patch)
tree1521f29ad032f1ab16a7838557a8c1e28f1414e1 /lib/libcrypto/rsa/rsa_oaep.c
parent68e1384c87c6264544ffca6394cdb172d13acde7 (diff)
import openssl-0.9.7-beta1
Diffstat (limited to 'lib/libcrypto/rsa/rsa_oaep.c')
-rw-r--r--lib/libcrypto/rsa/rsa_oaep.c162
1 files changed, 162 insertions, 0 deletions
diff --git a/lib/libcrypto/rsa/rsa_oaep.c b/lib/libcrypto/rsa/rsa_oaep.c
new file mode 100644
index 00000000000..843c40c8640
--- /dev/null
+++ b/lib/libcrypto/rsa/rsa_oaep.c
@@ -0,0 +1,162 @@
+/* crypto/rsa/rsa_oaep.c */
+/* Written by Ulf Moeller. This software is distributed on an "AS IS"
+ basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. */
+
+/* EME_OAEP as defined in RFC 2437 (PKCS #1 v2.0) */
+
+#if !defined(NO_SHA) && !defined(NO_SHA1)
+#include <stdio.h>
+#include "cryptlib.h"
+#include <openssl/bn.h>
+#include <openssl/rsa.h>
+#include <openssl/sha.h>
+#include <openssl/rand.h>
+
+int MGF1(unsigned char *mask, long len, unsigned char *seed, long seedlen);
+
+int RSA_padding_add_PKCS1_OAEP(unsigned char *to, int tlen,
+ unsigned char *from, int flen, unsigned char *param, int plen)
+ {
+ int i, emlen = tlen - 1;
+ unsigned char *db, *seed;
+ unsigned char *dbmask, seedmask[SHA_DIGEST_LENGTH];
+
+ if (flen > emlen - 2 * SHA_DIGEST_LENGTH - 1)
+ {
+ RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_OAEP,
+ RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
+ return (0);
+ }
+
+ if (emlen < 2 * SHA_DIGEST_LENGTH + 1)
+ {
+ RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_OAEP, RSA_R_KEY_SIZE_TOO_SMALL);
+ return (0);
+ }
+
+ dbmask = Malloc(emlen - SHA_DIGEST_LENGTH);
+ if (dbmask == NULL)
+ {
+ RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_OAEP, ERR_R_MALLOC_FAILURE);
+ return (0);
+ }
+
+ to[0] = 0;
+ seed = to + 1;
+ db = to + SHA_DIGEST_LENGTH + 1;
+
+ SHA1(param, plen, db);
+ memset(db + SHA_DIGEST_LENGTH, 0,
+ emlen - flen - 2 * SHA_DIGEST_LENGTH - 1);
+ db[emlen - flen - SHA_DIGEST_LENGTH - 1] = 0x01;
+ memcpy(db + emlen - flen - SHA_DIGEST_LENGTH, from, (unsigned int) flen);
+ RAND_bytes(seed, SHA_DIGEST_LENGTH);
+#ifdef PKCS_TESTVECT
+ memcpy(seed,
+ "\xaa\xfd\x12\xf6\x59\xca\xe6\x34\x89\xb4\x79\xe5\x07\x6d\xde\xc2\xf0\x6c\xb5\x8f",
+ 20);
+#endif
+
+ MGF1(dbmask, emlen - SHA_DIGEST_LENGTH, seed, SHA_DIGEST_LENGTH);
+ for (i = 0; i < emlen - SHA_DIGEST_LENGTH; i++)
+ db[i] ^= dbmask[i];
+
+ MGF1(seedmask, SHA_DIGEST_LENGTH, db, emlen - SHA_DIGEST_LENGTH);
+ for (i = 0; i < SHA_DIGEST_LENGTH; i++)
+ seed[i] ^= seedmask[i];
+
+ Free(dbmask);
+ return (1);
+ }
+
+int RSA_padding_check_PKCS1_OAEP(unsigned char *to, int tlen,
+ unsigned char *from, int flen, int num, unsigned char *param,
+ int plen)
+ {
+ int i, dblen, mlen = -1;
+ unsigned char *maskeddb;
+ int lzero;
+ unsigned char *db, seed[SHA_DIGEST_LENGTH], phash[SHA_DIGEST_LENGTH];
+
+ if (--num < 2 * SHA_DIGEST_LENGTH + 1)
+ {
+ RSAerr(RSA_F_RSA_PADDING_CHECK_PKCS1_OAEP, RSA_R_OAEP_DECODING_ERROR);
+ return (-1);
+ }
+
+ dblen = num - SHA_DIGEST_LENGTH;
+ db = Malloc(dblen);
+ if (db == NULL)
+ {
+ RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_OAEP, ERR_R_MALLOC_FAILURE);
+ return (-1);
+ }
+
+ lzero = num - flen;
+ maskeddb = from - lzero + SHA_DIGEST_LENGTH;
+
+ MGF1(seed, SHA_DIGEST_LENGTH, maskeddb, dblen);
+ for (i = lzero; i < SHA_DIGEST_LENGTH; i++)
+ seed[i] ^= from[i - lzero];
+
+ MGF1(db, dblen, seed, SHA_DIGEST_LENGTH);
+ for (i = 0; i < dblen; i++)
+ db[i] ^= maskeddb[i];
+
+ SHA1(param, plen, phash);
+
+ if (memcmp(db, phash, SHA_DIGEST_LENGTH) != 0)
+ RSAerr(RSA_F_RSA_PADDING_CHECK_PKCS1_OAEP, RSA_R_OAEP_DECODING_ERROR);
+ else
+ {
+ for (i = SHA_DIGEST_LENGTH; i < dblen; i++)
+ if (db[i] != 0x00)
+ break;
+ if (db[i] != 0x01 || i++ >= dblen)
+ RSAerr(RSA_F_RSA_PADDING_CHECK_PKCS1_OAEP,
+ RSA_R_OAEP_DECODING_ERROR);
+ else
+ {
+ mlen = dblen - i;
+ if (tlen < mlen)
+ {
+ RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_OAEP, RSA_R_DATA_TOO_LARGE);
+ mlen = -1;
+ }
+ else
+ memcpy(to, db + i, mlen);
+ }
+ }
+ Free(db);
+ return (mlen);
+ }
+
+int MGF1(unsigned char *mask, long len, unsigned char *seed, long seedlen)
+ {
+ long i, outlen = 0;
+ unsigned char cnt[4];
+ SHA_CTX c;
+ unsigned char md[SHA_DIGEST_LENGTH];
+
+ for (i = 0; outlen < len; i++)
+ {
+ cnt[0] = (i >> 24) & 255, cnt[1] = (i >> 16) & 255,
+ cnt[2] = (i >> 8) & 255, cnt[3] = i & 255;
+ SHA1_Init(&c);
+ SHA1_Update(&c, seed, seedlen);
+ SHA1_Update(&c, cnt, 4);
+ if (outlen + SHA_DIGEST_LENGTH <= len)
+ {
+ SHA1_Final(mask + outlen, &c);
+ outlen += SHA_DIGEST_LENGTH;
+ }
+ else
+ {
+ SHA1_Final(md, &c);
+ memcpy(mask + outlen, md, len - outlen);
+ outlen = len;
+ }
+ }
+ return (0);
+ }
+#endif