diff options
Diffstat (limited to 'openssl/crypto/rsa/rsa_oaep.c')
-rw-r--r-- | openssl/crypto/rsa/rsa_oaep.c | 233 |
1 files changed, 0 insertions, 233 deletions
diff --git a/openssl/crypto/rsa/rsa_oaep.c b/openssl/crypto/rsa/rsa_oaep.c deleted file mode 100644 index 18d307ea..00000000 --- a/openssl/crypto/rsa/rsa_oaep.c +++ /dev/null @@ -1,233 +0,0 @@ -/* 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) */ - -/* 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. - * - * A new proof can be found in E. Fujisaki, T. Okamoto, - * D. Pointcheval, J. Stern, "RSA-OEAP is Still Alive!", - * Dec. 2000, <URL: http://eprint.iacr.org/2000/061/>. - * The new proof has stronger requirements for the - * underlying permutation: "partial-one-wayness" instead - * of one-wayness. For the RSA function, this is - * an equivalent notion. - */ - - -#if !defined(OPENSSL_NO_SHA) && !defined(OPENSSL_NO_SHA1) -#include <stdio.h> -#include "cryptlib.h" -#include <openssl/bn.h> -#include <openssl/rsa.h> -#include <openssl/evp.h> -#include <openssl/rand.h> -#include <openssl/sha.h> - -static int MGF1(unsigned char *mask, long len, - const unsigned char *seed, long seedlen); - -int RSA_padding_add_PKCS1_OAEP(unsigned char *to, int tlen, - const unsigned char *from, int flen, - const 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; - } - - to[0] = 0; - seed = to + 1; - db = to + SHA_DIGEST_LENGTH + 1; - - EVP_Digest((void *)param, plen, db, NULL, EVP_sha1(), NULL); - 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); - if (RAND_bytes(seed, SHA_DIGEST_LENGTH) <= 0) - return 0; -#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 - - dbmask = OPENSSL_malloc(emlen - SHA_DIGEST_LENGTH); - if (dbmask == NULL) - { - RSAerr(RSA_F_RSA_PADDING_ADD_PKCS1_OAEP, ERR_R_MALLOC_FAILURE); - return 0; - } - - if (MGF1(dbmask, emlen - SHA_DIGEST_LENGTH, seed, SHA_DIGEST_LENGTH) < 0) - return 0; - for (i = 0; i < emlen - SHA_DIGEST_LENGTH; i++) - db[i] ^= dbmask[i]; - - if (MGF1(seedmask, SHA_DIGEST_LENGTH, db, emlen - SHA_DIGEST_LENGTH) < 0) - return 0; - for (i = 0; i < SHA_DIGEST_LENGTH; i++) - seed[i] ^= seedmask[i]; - - OPENSSL_free(dbmask); - return 1; - } - -int RSA_padding_check_PKCS1_OAEP(unsigned char *to, int tlen, - const unsigned char *from, int flen, int num, - const unsigned char *param, int plen) - { - int i, dblen, mlen = -1; - const unsigned char *maskeddb; - int lzero; - unsigned char *db = NULL, seed[SHA_DIGEST_LENGTH], phash[SHA_DIGEST_LENGTH]; - unsigned char *padded_from; - int bad = 0; - - if (--num < 2 * SHA_DIGEST_LENGTH + 1) - /* 'num' is the length of the modulus, i.e. does not depend on the - * particular ciphertext. */ - goto decoding_err; - - lzero = num - flen; - if (lzero < 0) - { - /* signalling this error immediately after detection might allow - * for side-channel attacks (e.g. timing if 'plen' is huge - * -- cf. James H. Manger, "A Chosen Ciphertext Attack on RSA Optimal - * Asymmetric Encryption Padding (OAEP) [...]", CRYPTO 2001), - * so we use a 'bad' flag */ - bad = 1; - lzero = 0; - flen = num; /* don't overflow the memcpy to padded_from */ - } - - dblen = num - SHA_DIGEST_LENGTH; - db = OPENSSL_malloc(dblen + num); - if (db == NULL) - { - RSAerr(RSA_F_RSA_PADDING_CHECK_PKCS1_OAEP, ERR_R_MALLOC_FAILURE); - return -1; - } - - /* Always do this zero-padding copy (even when lzero == 0) - * to avoid leaking timing info about the value of lzero. */ - padded_from = db + dblen; - memset(padded_from, 0, lzero); - memcpy(padded_from + lzero, from, flen); - - maskeddb = padded_from + SHA_DIGEST_LENGTH; - - if (MGF1(seed, SHA_DIGEST_LENGTH, maskeddb, dblen)) - return -1; - for (i = 0; i < SHA_DIGEST_LENGTH; i++) - seed[i] ^= padded_from[i]; - - if (MGF1(db, dblen, seed, SHA_DIGEST_LENGTH)) - return -1; - for (i = 0; i < dblen; i++) - db[i] ^= maskeddb[i]; - - EVP_Digest((void *)param, plen, phash, NULL, EVP_sha1(), NULL); - - if (memcmp(db, phash, SHA_DIGEST_LENGTH) != 0 || bad) - goto decoding_err; - else - { - for (i = SHA_DIGEST_LENGTH; i < dblen; i++) - if (db[i] != 0x00) - break; - if (i == dblen || db[i] != 0x01) - goto decoding_err; - else - { - /* everything looks OK */ - - mlen = dblen - ++i; - if (tlen < mlen) - { - RSAerr(RSA_F_RSA_PADDING_CHECK_PKCS1_OAEP, RSA_R_DATA_TOO_LARGE); - mlen = -1; - } - else - memcpy(to, db + i, mlen); - } - } - OPENSSL_free(db); - return mlen; - -decoding_err: - /* to avoid chosen ciphertext attacks, the error message should not reveal - * which kind of decoding error happened */ - RSAerr(RSA_F_RSA_PADDING_CHECK_PKCS1_OAEP, RSA_R_OAEP_DECODING_ERROR); - if (db != NULL) OPENSSL_free(db); - return -1; - } - -int PKCS1_MGF1(unsigned char *mask, long len, - const unsigned char *seed, long seedlen, const EVP_MD *dgst) - { - long i, outlen = 0; - unsigned char cnt[4]; - EVP_MD_CTX c; - unsigned char md[EVP_MAX_MD_SIZE]; - int mdlen; - int rv = -1; - - EVP_MD_CTX_init(&c); - mdlen = EVP_MD_size(dgst); - if (mdlen < 0) - goto err; - for (i = 0; outlen < len; i++) - { - cnt[0] = (unsigned char)((i >> 24) & 255); - cnt[1] = (unsigned char)((i >> 16) & 255); - cnt[2] = (unsigned char)((i >> 8)) & 255; - cnt[3] = (unsigned char)(i & 255); - if (!EVP_DigestInit_ex(&c,dgst, NULL) - || !EVP_DigestUpdate(&c, seed, seedlen) - || !EVP_DigestUpdate(&c, cnt, 4)) - goto err; - if (outlen + mdlen <= len) - { - if (!EVP_DigestFinal_ex(&c, mask + outlen, NULL)) - goto err; - outlen += mdlen; - } - else - { - if (!EVP_DigestFinal_ex(&c, md, NULL)) - goto err; - memcpy(mask + outlen, md, len - outlen); - outlen = len; - } - } - rv = 0; - err: - EVP_MD_CTX_cleanup(&c); - return rv; - } - -static int MGF1(unsigned char *mask, long len, const unsigned char *seed, - long seedlen) - { - return PKCS1_MGF1(mask, len, seed, seedlen, EVP_sha1()); - } -#endif |