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-rw-r--r--crypto/rsa/rsa_ameth.c6
-rw-r--r--crypto/rsa/rsa_gen.c5
-rw-r--r--crypto/rsa/rsa_oaep.c48
-rw-r--r--crypto/rsa/rsa_ossl.c16
-rw-r--r--crypto/rsa/rsa_pk1.c46
-rw-r--r--crypto/rsa/rsa_pmeth.c13
-rw-r--r--crypto/rsa/rsa_ssl.c57
-rw-r--r--crypto/rsa/rsa_x931g.c8
8 files changed, 99 insertions, 100 deletions
diff --git a/crypto/rsa/rsa_ameth.c b/crypto/rsa/rsa_ameth.c
index 75debb3e0a9d..ab5f61518bb1 100644
--- a/crypto/rsa/rsa_ameth.c
+++ b/crypto/rsa/rsa_ameth.c
@@ -1,5 +1,5 @@
/*
- * Copyright 2006-2018 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2006-2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
@@ -583,10 +583,12 @@ static RSA_PSS_PARAMS *rsa_ctx_to_pss(EVP_PKEY_CTX *pkctx)
return NULL;
if (saltlen == -1) {
saltlen = EVP_MD_size(sigmd);
- } else if (saltlen == -2) {
+ } else if (saltlen == -2 || saltlen == -3) {
saltlen = EVP_PKEY_size(pk) - EVP_MD_size(sigmd) - 2;
if ((EVP_PKEY_bits(pk) & 0x7) == 1)
saltlen--;
+ if (saltlen < 0)
+ return NULL;
}
return rsa_pss_params_create(sigmd, mgf1md, saltlen);
diff --git a/crypto/rsa/rsa_gen.c b/crypto/rsa/rsa_gen.c
index 7f0a25648140..4997a632f2d3 100644
--- a/crypto/rsa/rsa_gen.c
+++ b/crypto/rsa/rsa_gen.c
@@ -1,5 +1,5 @@
/*
- * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
@@ -387,8 +387,7 @@ static int rsa_builtin_keygen(RSA *rsa, int bits, int primes, BIGNUM *e_value,
RSAerr(RSA_F_RSA_BUILTIN_KEYGEN, ERR_LIB_BN);
ok = 0;
}
- if (ctx != NULL)
- BN_CTX_end(ctx);
+ BN_CTX_end(ctx);
BN_CTX_free(ctx);
return ok;
}
diff --git a/crypto/rsa/rsa_oaep.c b/crypto/rsa/rsa_oaep.c
index 689e6dc22292..48b888bf27ad 100644
--- a/crypto/rsa/rsa_oaep.c
+++ b/crypto/rsa/rsa_oaep.c
@@ -1,5 +1,5 @@
/*
- * Copyright 1999-2018 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1999-2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
@@ -143,7 +143,7 @@ int RSA_padding_check_PKCS1_OAEP_mgf1(unsigned char *to, int tlen,
* |num| is the length of the modulus; |flen| is the length of the
* encoded message. Therefore, for any |from| that was obtained by
* decrypting a ciphertext, we must have |flen| <= |num|. Similarly,
- * num < 2 * mdlen + 2 must hold for the modulus irrespective of
+ * |num| >= 2 * |mdlen| + 2 must hold for the modulus irrespective of
* the ciphertext, see PKCS #1 v2.2, section 7.1.2.
* This does not leak any side-channel information.
*/
@@ -179,17 +179,16 @@ int RSA_padding_check_PKCS1_OAEP_mgf1(unsigned char *to, int tlen,
from -= 1 & mask;
*--em = *from & mask;
}
- from = em;
/*
* The first byte must be zero, however we must not leak if this is
* true. See James H. Manger, "A Chosen Ciphertext Attack on RSA
* Optimal Asymmetric Encryption Padding (OAEP) [...]", CRYPTO 2001).
*/
- good = constant_time_is_zero(from[0]);
+ good = constant_time_is_zero(em[0]);
- maskedseed = from + 1;
- maskeddb = from + 1 + mdlen;
+ maskedseed = em + 1;
+ maskeddb = em + 1 + mdlen;
if (PKCS1_MGF1(seed, mdlen, maskeddb, dblen, mgf1md))
goto cleanup;
@@ -230,29 +229,30 @@ int RSA_padding_check_PKCS1_OAEP_mgf1(unsigned char *to, int tlen,
mlen = dblen - msg_index;
/*
- * For good measure, do this check in constant tine as well.
+ * For good measure, do this check in constant time as well.
*/
good &= constant_time_ge(tlen, mlen);
/*
- * Even though we can't fake result's length, we can pretend copying
- * |tlen| bytes where |mlen| bytes would be real. Last |tlen| of |dblen|
- * bytes are viewed as circular buffer with start at |tlen|-|mlen'|,
- * where |mlen'| is "saturated" |mlen| value. Deducing information
- * about failure or |mlen| would take attacker's ability to observe
- * memory access pattern with byte granularity *as it occurs*. It
- * should be noted that failure is indistinguishable from normal
- * operation if |tlen| is fixed by protocol.
+ * Move the result in-place by |dblen|-|mdlen|-1-|mlen| bytes to the left.
+ * Then if |good| move |mlen| bytes from |db|+|mdlen|+1 to |to|.
+ * Otherwise leave |to| unchanged.
+ * Copy the memory back in a way that does not reveal the size of
+ * the data being copied via a timing side channel. This requires copying
+ * parts of the buffer multiple times based on the bits set in the real
+ * length. Clear bits do a non-copy with identical access pattern.
+ * The loop below has overall complexity of O(N*log(N)).
*/
- tlen = constant_time_select_int(constant_time_lt(dblen, tlen), dblen, tlen);
- msg_index = constant_time_select_int(good, msg_index, dblen - tlen);
- mlen = dblen - msg_index;
- for (from = db + msg_index, mask = good, i = 0; i < tlen; i++) {
- unsigned int equals = constant_time_eq(i, mlen);
-
- from -= dblen & equals; /* if (i == dblen) rewind */
- mask &= mask ^ equals; /* if (i == dblen) mask = 0 */
- to[i] = constant_time_select_8(mask, from[i], to[i]);
+ tlen = constant_time_select_int(constant_time_lt(dblen - mdlen - 1, tlen),
+ dblen - mdlen - 1, tlen);
+ for (msg_index = 1; msg_index < dblen - mdlen - 1; msg_index <<= 1) {
+ mask = ~constant_time_eq(msg_index & (dblen - mdlen - 1 - mlen), 0);
+ for (i = mdlen + 1; i < dblen - msg_index; i++)
+ db[i] = constant_time_select_8(mask, db[i + msg_index], db[i]);
+ }
+ for (i = 0; i < tlen; i++) {
+ mask = good & constant_time_lt(i, mlen);
+ to[i] = constant_time_select_8(mask, db[i + mdlen + 1], to[i]);
}
/*
diff --git a/crypto/rsa/rsa_ossl.c b/crypto/rsa/rsa_ossl.c
index 465134257fcc..33be9ea8cb84 100644
--- a/crypto/rsa/rsa_ossl.c
+++ b/crypto/rsa/rsa_ossl.c
@@ -1,5 +1,5 @@
/*
- * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
@@ -148,8 +148,7 @@ static int rsa_ossl_public_encrypt(int flen, const unsigned char *from,
*/
r = BN_bn2binpad(ret, to, num);
err:
- if (ctx != NULL)
- BN_CTX_end(ctx);
+ BN_CTX_end(ctx);
BN_CTX_free(ctx);
OPENSSL_clear_free(buf, num);
return r;
@@ -354,8 +353,7 @@ static int rsa_ossl_private_encrypt(int flen, const unsigned char *from,
*/
r = BN_bn2binpad(res, to, num);
err:
- if (ctx != NULL)
- BN_CTX_end(ctx);
+ BN_CTX_end(ctx);
BN_CTX_free(ctx);
OPENSSL_clear_free(buf, num);
return r;
@@ -481,11 +479,10 @@ static int rsa_ossl_private_decrypt(int flen, const unsigned char *from,
goto err;
}
RSAerr(RSA_F_RSA_OSSL_PRIVATE_DECRYPT, RSA_R_PADDING_CHECK_FAILED);
- err_clear_last_constant_time(r >= 0);
+ err_clear_last_constant_time(1 & ~constant_time_msb(r));
err:
- if (ctx != NULL)
- BN_CTX_end(ctx);
+ BN_CTX_end(ctx);
BN_CTX_free(ctx);
OPENSSL_clear_free(buf, num);
return r;
@@ -581,8 +578,7 @@ static int rsa_ossl_public_decrypt(int flen, const unsigned char *from,
RSAerr(RSA_F_RSA_OSSL_PUBLIC_DECRYPT, RSA_R_PADDING_CHECK_FAILED);
err:
- if (ctx != NULL)
- BN_CTX_end(ctx);
+ BN_CTX_end(ctx);
BN_CTX_free(ctx);
OPENSSL_clear_free(buf, num);
return r;
diff --git a/crypto/rsa/rsa_pk1.c b/crypto/rsa/rsa_pk1.c
index 062690741809..5260d12f4c91 100644
--- a/crypto/rsa/rsa_pk1.c
+++ b/crypto/rsa/rsa_pk1.c
@@ -1,5 +1,5 @@
/*
- * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
@@ -192,15 +192,14 @@ int RSA_padding_check_PKCS1_type_2(unsigned char *to, int tlen,
from -= 1 & mask;
*--em = *from & mask;
}
- from = em;
- good = constant_time_is_zero(from[0]);
- good &= constant_time_eq(from[1], 2);
+ good = constant_time_is_zero(em[0]);
+ good &= constant_time_eq(em[1], 2);
/* scan over padding data */
found_zero_byte = 0;
for (i = 2; i < num; i++) {
- unsigned int equals0 = constant_time_is_zero(from[i]);
+ unsigned int equals0 = constant_time_is_zero(em[i]);
zero_index = constant_time_select_int(~found_zero_byte & equals0,
i, zero_index);
@@ -208,7 +207,7 @@ int RSA_padding_check_PKCS1_type_2(unsigned char *to, int tlen,
}
/*
- * PS must be at least 8 bytes long, and it starts two bytes into |from|.
+ * PS must be at least 8 bytes long, and it starts two bytes into |em|.
* If we never found a 0-byte, then |zero_index| is 0 and the check
* also fails.
*/
@@ -227,24 +226,25 @@ int RSA_padding_check_PKCS1_type_2(unsigned char *to, int tlen,
good &= constant_time_ge(tlen, mlen);
/*
- * Even though we can't fake result's length, we can pretend copying
- * |tlen| bytes where |mlen| bytes would be real. Last |tlen| of |num|
- * bytes are viewed as circular buffer with start at |tlen|-|mlen'|,
- * where |mlen'| is "saturated" |mlen| value. Deducing information
- * about failure or |mlen| would take attacker's ability to observe
- * memory access pattern with byte granularity *as it occurs*. It
- * should be noted that failure is indistinguishable from normal
- * operation if |tlen| is fixed by protocol.
+ * Move the result in-place by |num|-11-|mlen| bytes to the left.
+ * Then if |good| move |mlen| bytes from |em|+11 to |to|.
+ * Otherwise leave |to| unchanged.
+ * Copy the memory back in a way that does not reveal the size of
+ * the data being copied via a timing side channel. This requires copying
+ * parts of the buffer multiple times based on the bits set in the real
+ * length. Clear bits do a non-copy with identical access pattern.
+ * The loop below has overall complexity of O(N*log(N)).
*/
- tlen = constant_time_select_int(constant_time_lt(num, tlen), num, tlen);
- msg_index = constant_time_select_int(good, msg_index, num - tlen);
- mlen = num - msg_index;
- for (from += msg_index, mask = good, i = 0; i < tlen; i++) {
- unsigned int equals = constant_time_eq(i, mlen);
-
- from -= tlen & equals; /* if (i == mlen) rewind */
- mask &= mask ^ equals; /* if (i == mlen) mask = 0 */
- to[i] = constant_time_select_8(mask, from[i], to[i]);
+ tlen = constant_time_select_int(constant_time_lt(num - 11, tlen),
+ num - 11, tlen);
+ for (msg_index = 1; msg_index < num - 11; msg_index <<= 1) {
+ mask = ~constant_time_eq(msg_index & (num - 11 - mlen), 0);
+ for (i = 11; i < num - msg_index; i++)
+ em[i] = constant_time_select_8(mask, em[i + msg_index], em[i]);
+ }
+ for (i = 0; i < tlen; i++) {
+ mask = good & constant_time_lt(i, mlen);
+ to[i] = constant_time_select_8(mask, em[i + 11], to[i]);
}
OPENSSL_clear_free(em, num);
diff --git a/crypto/rsa/rsa_pmeth.c b/crypto/rsa/rsa_pmeth.c
index c10669f8a91b..082ab8fd8a1f 100644
--- a/crypto/rsa/rsa_pmeth.c
+++ b/crypto/rsa/rsa_pmeth.c
@@ -1,5 +1,5 @@
/*
- * Copyright 2006-2018 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2006-2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
@@ -7,6 +7,8 @@
* https://www.openssl.org/source/license.html
*/
+#include "internal/constant_time_locl.h"
+
#include <stdio.h>
#include "internal/cryptlib.h"
#include <openssl/asn1t.h>
@@ -54,7 +56,7 @@ static int pkey_rsa_init(EVP_PKEY_CTX *ctx)
if (rctx == NULL)
return 0;
- rctx->nbits = 1024;
+ rctx->nbits = 2048;
rctx->primes = RSA_DEFAULT_PRIME_NUM;
if (pkey_ctx_is_pss(ctx))
rctx->pad_mode = RSA_PKCS1_PSS_PADDING;
@@ -340,10 +342,9 @@ static int pkey_rsa_decrypt(EVP_PKEY_CTX *ctx,
ret = RSA_private_decrypt(inlen, in, out, ctx->pkey->pkey.rsa,
rctx->pad_mode);
}
- if (ret < 0)
- return ret;
- *outlen = ret;
- return 1;
+ *outlen = constant_time_select_s(constant_time_msb_s(ret), *outlen, ret);
+ ret = constant_time_select_int(constant_time_msb(ret), ret, 1);
+ return ret;
}
static int check_padding_md(const EVP_MD *md, int padding)
diff --git a/crypto/rsa/rsa_ssl.c b/crypto/rsa/rsa_ssl.c
index c5654595fb2f..3859128a6d80 100644
--- a/crypto/rsa/rsa_ssl.c
+++ b/crypto/rsa/rsa_ssl.c
@@ -1,5 +1,5 @@
/*
- * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
@@ -55,7 +55,7 @@ int RSA_padding_add_SSLv23(unsigned char *to, int tlen,
/*
* Copy of RSA_padding_check_PKCS1_type_2 with a twist that rejects padding
- * if nul delimiter is preceded by 8 consecutive 0x03 bytes. It also
+ * if nul delimiter is not preceded by 8 consecutive 0x03 bytes. It also
* preserves error code reporting for backward compatibility.
*/
int RSA_padding_check_SSLv23(unsigned char *to, int tlen,
@@ -67,7 +67,10 @@ int RSA_padding_check_SSLv23(unsigned char *to, int tlen,
unsigned int good, found_zero_byte, mask, threes_in_row;
int zero_index = 0, msg_index, mlen = -1, err;
- if (flen < 10) {
+ if (tlen <= 0 || flen <= 0)
+ return -1;
+
+ if (flen > num || num < 11) {
RSAerr(RSA_F_RSA_PADDING_CHECK_SSLV23, RSA_R_DATA_TOO_SMALL);
return -1;
}
@@ -89,10 +92,9 @@ int RSA_padding_check_SSLv23(unsigned char *to, int tlen,
from -= 1 & mask;
*--em = *from & mask;
}
- from = em;
- good = constant_time_is_zero(from[0]);
- good &= constant_time_eq(from[1], 2);
+ good = constant_time_is_zero(em[0]);
+ good &= constant_time_eq(em[1], 2);
err = constant_time_select_int(good, 0, RSA_R_BLOCK_TYPE_IS_NOT_02);
mask = ~good;
@@ -100,18 +102,18 @@ int RSA_padding_check_SSLv23(unsigned char *to, int tlen,
found_zero_byte = 0;
threes_in_row = 0;
for (i = 2; i < num; i++) {
- unsigned int equals0 = constant_time_is_zero(from[i]);
+ unsigned int equals0 = constant_time_is_zero(em[i]);
zero_index = constant_time_select_int(~found_zero_byte & equals0,
i, zero_index);
found_zero_byte |= equals0;
threes_in_row += 1 & ~found_zero_byte;
- threes_in_row &= found_zero_byte | constant_time_eq(from[i], 3);
+ threes_in_row &= found_zero_byte | constant_time_eq(em[i], 3);
}
/*
- * PS must be at least 8 bytes long, and it starts two bytes into |from|.
+ * PS must be at least 8 bytes long, and it starts two bytes into |em|.
* If we never found a 0-byte, then |zero_index| is 0 and the check
* also fails.
*/
@@ -120,7 +122,7 @@ int RSA_padding_check_SSLv23(unsigned char *to, int tlen,
RSA_R_NULL_BEFORE_BLOCK_MISSING);
mask = ~good;
- good &= constant_time_lt(threes_in_row, 8);
+ good &= constant_time_ge(threes_in_row, 8);
err = constant_time_select_int(mask | good, err,
RSA_R_SSLV3_ROLLBACK_ATTACK);
mask = ~good;
@@ -139,24 +141,25 @@ int RSA_padding_check_SSLv23(unsigned char *to, int tlen,
err = constant_time_select_int(mask | good, err, RSA_R_DATA_TOO_LARGE);
/*
- * Even though we can't fake result's length, we can pretend copying
- * |tlen| bytes where |mlen| bytes would be real. Last |tlen| of |num|
- * bytes are viewed as circular buffer with start at |tlen|-|mlen'|,
- * where |mlen'| is "saturated" |mlen| value. Deducing information
- * about failure or |mlen| would take attacker's ability to observe
- * memory access pattern with byte granularity *as it occurs*. It
- * should be noted that failure is indistinguishable from normal
- * operation if |tlen| is fixed by protocol.
+ * Move the result in-place by |num|-11-|mlen| bytes to the left.
+ * Then if |good| move |mlen| bytes from |em|+11 to |to|.
+ * Otherwise leave |to| unchanged.
+ * Copy the memory back in a way that does not reveal the size of
+ * the data being copied via a timing side channel. This requires copying
+ * parts of the buffer multiple times based on the bits set in the real
+ * length. Clear bits do a non-copy with identical access pattern.
+ * The loop below has overall complexity of O(N*log(N)).
*/
- tlen = constant_time_select_int(constant_time_lt(num, tlen), num, tlen);
- msg_index = constant_time_select_int(good, msg_index, num - tlen);
- mlen = num - msg_index;
- for (from += msg_index, mask = good, i = 0; i < tlen; i++) {
- unsigned int equals = constant_time_eq(i, mlen);
-
- from -= tlen & equals; /* if (i == mlen) rewind */
- mask &= mask ^ equals; /* if (i == mlen) mask = 0 */
- to[i] = constant_time_select_8(mask, from[i], to[i]);
+ tlen = constant_time_select_int(constant_time_lt(num - 11, tlen),
+ num - 11, tlen);
+ for (msg_index = 1; msg_index < num - 11; msg_index <<= 1) {
+ mask = ~constant_time_eq(msg_index & (num - 11 - mlen), 0);
+ for (i = 11; i < num - msg_index; i++)
+ em[i] = constant_time_select_8(mask, em[i + msg_index], em[i]);
+ }
+ for (i = 0; i < tlen; i++) {
+ mask = good & constant_time_lt(i, mlen);
+ to[i] = constant_time_select_8(mask, em[i + 11], to[i]);
}
OPENSSL_clear_free(em, num);
diff --git a/crypto/rsa/rsa_x931g.c b/crypto/rsa/rsa_x931g.c
index 15e40e8d1dd7..e7ac476bb4a4 100644
--- a/crypto/rsa/rsa_x931g.c
+++ b/crypto/rsa/rsa_x931g.c
@@ -1,5 +1,5 @@
/*
- * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
@@ -133,8 +133,7 @@ int RSA_X931_derive_ex(RSA *rsa, BIGNUM *p1, BIGNUM *p2, BIGNUM *q1,
ret = 1;
err:
- if (ctx)
- BN_CTX_end(ctx);
+ BN_CTX_end(ctx);
BN_CTX_free(ctx);
BN_CTX_free(ctx2);
@@ -188,8 +187,7 @@ int RSA_X931_generate_key_ex(RSA *rsa, int bits, const BIGNUM *e,
ok = 1;
error:
- if (ctx)
- BN_CTX_end(ctx);
+ BN_CTX_end(ctx);
BN_CTX_free(ctx);
if (ok)