diff options
Diffstat (limited to 'crypto/rsa/rsa_oaep.c')
| -rw-r--r-- | crypto/rsa/rsa_oaep.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/crypto/rsa/rsa_oaep.c b/crypto/rsa/rsa_oaep.c index fd0b7f361f..8d306d1ead 100644 --- a/crypto/rsa/rsa_oaep.c +++ b/crypto/rsa/rsa_oaep.c @@ -2,7 +2,22 @@ /* 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) */ +/* EME-OAEP as defined in RFC 2437 (PKCS #1 v2.0) */ + +/* See Victor Shoup, "OAEP reconsidered," Nov. 2000, + * <URL: http://www.shoup.net/papers/oaep.ps.Z> + * for problems with the security proof for the + * original OAEP scheme, which EME-OAEP is based on. + * + * Note that for RSA OAEP a security proof in the + * random oracle model *does* exist if 160 < log_2(N/e); + * cf. section 7.2 ("But RSA-OAEP with exponent 3 is + * provably secure") of Shoup's paper. (The slight + * differences between the OAEP definition used by Shoup + * and OAEP as defined in RFC 2437 should not affect + * this result.) + */ + #if !defined(NO_SHA) && !defined(NO_SHA1) #include <stdio.h> @@ -12,10 +27,12 @@ #include <openssl/sha.h> #include <openssl/rand.h> -int MGF1(unsigned char *mask, long len, unsigned char *seed, long seedlen); +int MGF1(unsigned char *mask, long len, + const 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) + const unsigned char *from, int flen, + const unsigned char *param, int plen) { int i, emlen = tlen - 1; unsigned char *db, *seed; @@ -71,11 +88,11 @@ int RSA_padding_add_PKCS1_OAEP(unsigned char *to, int tlen, } int RSA_padding_check_PKCS1_OAEP(unsigned char *to, int tlen, - unsigned char *from, int flen, int num, unsigned char *param, - int plen) + const unsigned char *from, int flen, int num, + const unsigned char *param, int plen) { int i, dblen, mlen = -1; - unsigned char *maskeddb; + const unsigned char *maskeddb; int lzero; unsigned char *db, seed[SHA_DIGEST_LENGTH], phash[SHA_DIGEST_LENGTH]; @@ -132,7 +149,8 @@ int RSA_padding_check_PKCS1_OAEP(unsigned char *to, int tlen, return (mlen); } -int MGF1(unsigned char *mask, long len, unsigned char *seed, long seedlen) +int MGF1(unsigned char *mask, long len, + const unsigned char *seed, long seedlen) { long i, outlen = 0; unsigned char cnt[4]; |