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Imported OpenSSL 1.1.1c

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This commit is contained in:
Steve Dower
2019-06-17 08:35:38 -07:00
parent cf34d7b72e
commit ea3c37b9ec
196 changed files with 38947 additions and 2649 deletions
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46
crypto/rsa/rsa_pk1.c
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@@ -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);