Move RSA (en|de)cryption out of the FIPS module.
Change-Id: I330ac0fa7f0b2c9984d12da831d8f34019ea2c49 Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/58526 Reviewed-by: David Benjamin <davidben@google.com> Commit-Queue: Adam Langley <agl@google.com>
This commit is contained in:
parent
7b9b9baa95
commit
89de6e1afe
@ -204,6 +204,7 @@ add_library(
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refcount_c11.c
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refcount_lock.c
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rsa_extra/rsa_asn1.c
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rsa_extra/rsa_crypt.c
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rsa_extra/rsa_print.c
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stack/stack.c
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siphash/siphash.c
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@ -67,7 +67,7 @@
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#include <openssl/rsa.h>
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#include "../internal.h"
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#include "../fipsmodule/rsa/internal.h"
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#include "../rsa_extra/internal.h"
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#include "internal.h"
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@ -67,6 +67,8 @@ extern "C" {
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#endif
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#define RSA_PKCS1_PADDING_SIZE 11
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// Default implementations of RSA operations.
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const RSA_METHOD *RSA_default_method(void);
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@ -75,8 +77,6 @@ size_t rsa_default_size(const RSA *rsa);
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int rsa_default_sign_raw(RSA *rsa, size_t *out_len, uint8_t *out,
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size_t max_out, const uint8_t *in, size_t in_len,
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int padding);
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int rsa_default_decrypt(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
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const uint8_t *in, size_t in_len, int padding);
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int rsa_default_private_transform(RSA *rsa, uint8_t *out, const uint8_t *in,
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size_t len);
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@ -90,21 +90,13 @@ int BN_BLINDING_invert(BIGNUM *n, const BN_BLINDING *b, BN_MONT_CTX *mont_ctx,
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BN_CTX *ctx);
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int PKCS1_MGF1(uint8_t *out, size_t len, const uint8_t *seed, size_t seed_len,
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const EVP_MD *md);
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int RSA_padding_add_PKCS1_type_1(uint8_t *to, size_t to_len,
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const uint8_t *from, size_t from_len);
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int RSA_padding_check_PKCS1_type_1(uint8_t *out, size_t *out_len,
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size_t max_out, const uint8_t *from,
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size_t from_len);
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int RSA_padding_add_PKCS1_type_2(uint8_t *to, size_t to_len,
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const uint8_t *from, size_t from_len);
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int RSA_padding_check_PKCS1_type_2(uint8_t *out, size_t *out_len,
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size_t max_out, const uint8_t *from,
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size_t from_len);
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int RSA_padding_check_PKCS1_OAEP_mgf1(uint8_t *out, size_t *out_len,
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size_t max_out, const uint8_t *from,
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size_t from_len, const uint8_t *param,
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size_t param_len, const EVP_MD *md,
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const EVP_MD *mgf1md);
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int RSA_padding_add_none(uint8_t *to, size_t to_len, const uint8_t *from,
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size_t from_len);
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@ -112,10 +104,16 @@ int RSA_padding_add_none(uint8_t *to, size_t to_len, const uint8_t *from,
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// within DoS bounds.
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int rsa_check_public_key(const RSA *rsa);
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// RSA_private_transform calls either the method-specific |private_transform|
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// function (if given) or the generic one. See the comment for
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// |private_transform| in |rsa_meth_st|.
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int RSA_private_transform(RSA *rsa, uint8_t *out, const uint8_t *in,
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// rsa_private_transform_no_self_test calls either the method-specific
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// |private_transform| function (if given) or the generic one. See the comment
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// for |private_transform| in |rsa_meth_st|.
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int rsa_private_transform_no_self_test(RSA *rsa, uint8_t *out,
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const uint8_t *in, size_t len);
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// rsa_private_transform acts the same as |rsa_private_transform_no_self_test|
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// but, in FIPS mode, performs an RSA self test before calling the default RSA
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// implementation.
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int rsa_private_transform(RSA *rsa, uint8_t *out, const uint8_t *in,
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size_t len);
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@ -71,8 +71,6 @@
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#include "../../internal.h"
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#define RSA_PKCS1_PADDING_SIZE 11
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int RSA_padding_add_PKCS1_type_1(uint8_t *to, size_t to_len,
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const uint8_t *from, size_t from_len) {
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// See RFC 8017, section 9.2.
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@ -146,109 +144,6 @@ int RSA_padding_check_PKCS1_type_1(uint8_t *out, size_t *out_len,
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return 1;
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}
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static void rand_nonzero(uint8_t *out, size_t len) {
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FIPS_service_indicator_lock_state();
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RAND_bytes(out, len);
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for (size_t i = 0; i < len; i++) {
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while (out[i] == 0) {
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RAND_bytes(out + i, 1);
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}
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}
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FIPS_service_indicator_unlock_state();
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}
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int RSA_padding_add_PKCS1_type_2(uint8_t *to, size_t to_len,
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const uint8_t *from, size_t from_len) {
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// See RFC 8017, section 7.2.1.
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if (to_len < RSA_PKCS1_PADDING_SIZE) {
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OPENSSL_PUT_ERROR(RSA, RSA_R_KEY_SIZE_TOO_SMALL);
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return 0;
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}
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if (from_len > to_len - RSA_PKCS1_PADDING_SIZE) {
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OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
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return 0;
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}
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to[0] = 0;
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to[1] = 2;
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size_t padding_len = to_len - 3 - from_len;
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rand_nonzero(to + 2, padding_len);
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to[2 + padding_len] = 0;
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OPENSSL_memcpy(to + to_len - from_len, from, from_len);
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return 1;
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}
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int RSA_padding_check_PKCS1_type_2(uint8_t *out, size_t *out_len,
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size_t max_out, const uint8_t *from,
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size_t from_len) {
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if (from_len == 0) {
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OPENSSL_PUT_ERROR(RSA, RSA_R_EMPTY_PUBLIC_KEY);
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return 0;
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}
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// PKCS#1 v1.5 decryption. See "PKCS #1 v2.2: RSA Cryptography
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// Standard", section 7.2.2.
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if (from_len < RSA_PKCS1_PADDING_SIZE) {
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// |from| is zero-padded to the size of the RSA modulus, a public value, so
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// this can be rejected in non-constant time.
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OPENSSL_PUT_ERROR(RSA, RSA_R_KEY_SIZE_TOO_SMALL);
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return 0;
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}
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crypto_word_t first_byte_is_zero = constant_time_eq_w(from[0], 0);
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crypto_word_t second_byte_is_two = constant_time_eq_w(from[1], 2);
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crypto_word_t zero_index = 0, looking_for_index = CONSTTIME_TRUE_W;
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for (size_t i = 2; i < from_len; i++) {
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crypto_word_t equals0 = constant_time_is_zero_w(from[i]);
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zero_index =
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constant_time_select_w(looking_for_index & equals0, i, zero_index);
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looking_for_index = constant_time_select_w(equals0, 0, looking_for_index);
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}
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// The input must begin with 00 02.
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crypto_word_t valid_index = first_byte_is_zero;
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valid_index &= second_byte_is_two;
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// We must have found the end of PS.
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valid_index &= ~looking_for_index;
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// PS must be at least 8 bytes long, and it starts two bytes into |from|.
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valid_index &= constant_time_ge_w(zero_index, 2 + 8);
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// Skip the zero byte.
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zero_index++;
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// NOTE: Although this logic attempts to be constant time, the API contracts
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// of this function and |RSA_decrypt| with |RSA_PKCS1_PADDING| make it
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// impossible to completely avoid Bleichenbacher's attack. Consumers should
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// use |RSA_PADDING_NONE| and perform the padding check in constant-time
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// combined with a swap to a random session key or other mitigation.
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CONSTTIME_DECLASSIFY(&valid_index, sizeof(valid_index));
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CONSTTIME_DECLASSIFY(&zero_index, sizeof(zero_index));
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if (!valid_index) {
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OPENSSL_PUT_ERROR(RSA, RSA_R_PKCS_DECODING_ERROR);
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return 0;
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}
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const size_t msg_len = from_len - zero_index;
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if (msg_len > max_out) {
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// This shouldn't happen because this function is always called with
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// |max_out| as the key size and |from_len| is bounded by the key size.
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OPENSSL_PUT_ERROR(RSA, RSA_R_PKCS_DECODING_ERROR);
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return 0;
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}
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OPENSSL_memcpy(out, &from[zero_index], msg_len);
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*out_len = msg_len;
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return 1;
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}
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int RSA_padding_add_none(uint8_t *to, size_t to_len, const uint8_t *from,
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size_t from_len) {
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if (from_len > to_len) {
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@ -265,8 +160,8 @@ int RSA_padding_add_none(uint8_t *to, size_t to_len, const uint8_t *from,
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return 1;
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}
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static int PKCS1_MGF1(uint8_t *out, size_t len, const uint8_t *seed,
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size_t seed_len, const EVP_MD *md) {
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int PKCS1_MGF1(uint8_t *out, size_t len, const uint8_t *seed, size_t seed_len,
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const EVP_MD *md) {
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int ret = 0;
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EVP_MD_CTX ctx;
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EVP_MD_CTX_init(&ctx);
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@ -310,184 +205,6 @@ err:
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return ret;
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}
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int RSA_padding_add_PKCS1_OAEP_mgf1(uint8_t *to, size_t to_len,
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const uint8_t *from, size_t from_len,
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const uint8_t *param, size_t param_len,
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const EVP_MD *md, const EVP_MD *mgf1md) {
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if (md == NULL) {
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md = EVP_sha1();
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}
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if (mgf1md == NULL) {
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mgf1md = md;
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}
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size_t mdlen = EVP_MD_size(md);
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if (to_len < 2 * mdlen + 2) {
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OPENSSL_PUT_ERROR(RSA, RSA_R_KEY_SIZE_TOO_SMALL);
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return 0;
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}
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size_t emlen = to_len - 1;
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if (from_len > emlen - 2 * mdlen - 1) {
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OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
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return 0;
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}
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if (emlen < 2 * mdlen + 1) {
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OPENSSL_PUT_ERROR(RSA, RSA_R_KEY_SIZE_TOO_SMALL);
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return 0;
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}
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to[0] = 0;
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uint8_t *seed = to + 1;
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uint8_t *db = to + mdlen + 1;
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uint8_t *dbmask = NULL;
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int ret = 0;
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FIPS_service_indicator_lock_state();
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if (!EVP_Digest(param, param_len, db, NULL, md, NULL)) {
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goto out;
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}
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OPENSSL_memset(db + mdlen, 0, emlen - from_len - 2 * mdlen - 1);
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db[emlen - from_len - mdlen - 1] = 0x01;
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OPENSSL_memcpy(db + emlen - from_len - mdlen, from, from_len);
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if (!RAND_bytes(seed, mdlen)) {
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goto out;
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}
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dbmask = OPENSSL_malloc(emlen - mdlen);
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if (dbmask == NULL) {
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goto out;
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}
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if (!PKCS1_MGF1(dbmask, emlen - mdlen, seed, mdlen, mgf1md)) {
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goto out;
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}
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for (size_t i = 0; i < emlen - mdlen; i++) {
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db[i] ^= dbmask[i];
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}
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uint8_t seedmask[EVP_MAX_MD_SIZE];
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if (!PKCS1_MGF1(seedmask, mdlen, db, emlen - mdlen, mgf1md)) {
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goto out;
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}
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for (size_t i = 0; i < mdlen; i++) {
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seed[i] ^= seedmask[i];
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}
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ret = 1;
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out:
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OPENSSL_free(dbmask);
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FIPS_service_indicator_unlock_state();
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return ret;
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}
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int RSA_padding_check_PKCS1_OAEP_mgf1(uint8_t *out, size_t *out_len,
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size_t max_out, const uint8_t *from,
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size_t from_len, const uint8_t *param,
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size_t param_len, const EVP_MD *md,
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const EVP_MD *mgf1md) {
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uint8_t *db = NULL;
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if (md == NULL) {
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md = EVP_sha1();
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}
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if (mgf1md == NULL) {
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mgf1md = md;
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}
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size_t mdlen = EVP_MD_size(md);
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// The encoded message is one byte smaller than the modulus to ensure that it
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// doesn't end up greater than the modulus. Thus there's an extra "+1" here
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// compared to https://tools.ietf.org/html/rfc2437#section-9.1.1.2.
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if (from_len < 1 + 2*mdlen + 1) {
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// 'from_len' is the length of the modulus, i.e. does not depend on the
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// particular ciphertext.
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goto decoding_err;
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}
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size_t dblen = from_len - mdlen - 1;
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FIPS_service_indicator_lock_state();
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db = OPENSSL_malloc(dblen);
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if (db == NULL) {
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goto err;
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}
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const uint8_t *maskedseed = from + 1;
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const uint8_t *maskeddb = from + 1 + mdlen;
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uint8_t seed[EVP_MAX_MD_SIZE];
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if (!PKCS1_MGF1(seed, mdlen, maskeddb, dblen, mgf1md)) {
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goto err;
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}
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for (size_t i = 0; i < mdlen; i++) {
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seed[i] ^= maskedseed[i];
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}
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if (!PKCS1_MGF1(db, dblen, seed, mdlen, mgf1md)) {
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goto err;
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}
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for (size_t i = 0; i < dblen; i++) {
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db[i] ^= maskeddb[i];
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}
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uint8_t phash[EVP_MAX_MD_SIZE];
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if (!EVP_Digest(param, param_len, phash, NULL, md, NULL)) {
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goto err;
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}
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crypto_word_t bad = ~constant_time_is_zero_w(CRYPTO_memcmp(db, phash, mdlen));
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bad |= ~constant_time_is_zero_w(from[0]);
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crypto_word_t looking_for_one_byte = CONSTTIME_TRUE_W;
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size_t one_index = 0;
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for (size_t i = mdlen; i < dblen; i++) {
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crypto_word_t equals1 = constant_time_eq_w(db[i], 1);
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crypto_word_t equals0 = constant_time_eq_w(db[i], 0);
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one_index =
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constant_time_select_w(looking_for_one_byte & equals1, i, one_index);
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looking_for_one_byte =
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constant_time_select_w(equals1, 0, looking_for_one_byte);
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bad |= looking_for_one_byte & ~equals0;
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}
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bad |= looking_for_one_byte;
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// Whether the overall padding was valid or not in OAEP is public.
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if (constant_time_declassify_w(bad)) {
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goto decoding_err;
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}
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// Once the padding is known to be valid, the output length is also public.
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static_assert(sizeof(size_t) <= sizeof(crypto_word_t),
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"size_t does not fit in crypto_word_t");
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one_index = constant_time_declassify_w(one_index);
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one_index++;
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size_t mlen = dblen - one_index;
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if (max_out < mlen) {
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OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE);
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goto err;
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}
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OPENSSL_memcpy(out, db + one_index, mlen);
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*out_len = mlen;
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OPENSSL_free(db);
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FIPS_service_indicator_unlock_state();
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return 1;
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decoding_err:
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// To avoid chosen ciphertext attacks, the error message should not reveal
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// which kind of decoding error happened.
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OPENSSL_PUT_ERROR(RSA, RSA_R_OAEP_DECODING_ERROR);
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err:
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OPENSSL_free(db);
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FIPS_service_indicator_unlock_state();
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return 0;
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}
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static const uint8_t kPSSZeroes[] = {0, 0, 0, 0, 0, 0, 0, 0};
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int RSA_verify_PKCS1_PSS_mgf1(const RSA *rsa, const uint8_t *mHash,
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@ -504,9 +221,9 @@ int RSA_verify_PKCS1_PSS_mgf1(const RSA *rsa, const uint8_t *mHash,
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FIPS_service_indicator_lock_state();
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// Negative sLen has special meanings:
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// -1 sLen == hLen
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// -2 salt length is autorecovered from signature
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// -N reserved
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// -1 sLen == hLen
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// -2 salt length is autorecovered from signature
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// -N reserved
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size_t hLen = EVP_MD_size(Hash);
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if (sLen == -1) {
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sLen = (int)hLen;
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|
@ -288,21 +288,6 @@ int RSA_set0_crt_params(RSA *rsa, BIGNUM *dmp1, BIGNUM *dmq1, BIGNUM *iqmp) {
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return 1;
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}
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|
||||
int RSA_public_encrypt(size_t flen, const uint8_t *from, uint8_t *to, RSA *rsa,
|
||||
int padding) {
|
||||
size_t out_len;
|
||||
|
||||
if (!RSA_encrypt(rsa, &out_len, to, RSA_size(rsa), from, flen, padding)) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (out_len > INT_MAX) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
|
||||
return -1;
|
||||
}
|
||||
return (int)out_len;
|
||||
}
|
||||
|
||||
static int rsa_sign_raw_no_self_test(RSA *rsa, size_t *out_len, uint8_t *out,
|
||||
size_t max_out, const uint8_t *in,
|
||||
size_t in_len, int padding) {
|
||||
@ -320,58 +305,6 @@ int RSA_sign_raw(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
|
||||
padding);
|
||||
}
|
||||
|
||||
int RSA_private_encrypt(size_t flen, const uint8_t *from, uint8_t *to, RSA *rsa,
|
||||
int padding) {
|
||||
size_t out_len;
|
||||
|
||||
if (!RSA_sign_raw(rsa, &out_len, to, RSA_size(rsa), from, flen, padding)) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (out_len > INT_MAX) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
|
||||
return -1;
|
||||
}
|
||||
return (int)out_len;
|
||||
}
|
||||
|
||||
int RSA_decrypt(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
|
||||
const uint8_t *in, size_t in_len, int padding) {
|
||||
if (rsa->meth->decrypt) {
|
||||
return rsa->meth->decrypt(rsa, out_len, out, max_out, in, in_len, padding);
|
||||
}
|
||||
|
||||
return rsa_default_decrypt(rsa, out_len, out, max_out, in, in_len, padding);
|
||||
}
|
||||
|
||||
int RSA_private_decrypt(size_t flen, const uint8_t *from, uint8_t *to, RSA *rsa,
|
||||
int padding) {
|
||||
size_t out_len;
|
||||
if (!RSA_decrypt(rsa, &out_len, to, RSA_size(rsa), from, flen, padding)) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (out_len > INT_MAX) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
|
||||
return -1;
|
||||
}
|
||||
return (int)out_len;
|
||||
}
|
||||
|
||||
int RSA_public_decrypt(size_t flen, const uint8_t *from, uint8_t *to, RSA *rsa,
|
||||
int padding) {
|
||||
size_t out_len;
|
||||
if (!RSA_verify_raw(rsa, &out_len, to, RSA_size(rsa), from, flen, padding)) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (out_len > INT_MAX) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
|
||||
return -1;
|
||||
}
|
||||
return (int)out_len;
|
||||
}
|
||||
|
||||
unsigned RSA_size(const RSA *rsa) {
|
||||
size_t ret = rsa->meth->size ? rsa->meth->size(rsa) : rsa_default_size(rsa);
|
||||
// RSA modulus sizes are bounded by |BIGNUM|, which must fit in |unsigned|.
|
||||
@ -962,8 +895,8 @@ cleanup:
|
||||
return ret;
|
||||
}
|
||||
|
||||
int RSA_private_transform(RSA *rsa, uint8_t *out, const uint8_t *in,
|
||||
size_t len) {
|
||||
int rsa_private_transform_no_self_test(RSA *rsa, uint8_t *out,
|
||||
const uint8_t *in, size_t len) {
|
||||
if (rsa->meth->private_transform) {
|
||||
return rsa->meth->private_transform(rsa, out, in, len);
|
||||
}
|
||||
@ -971,6 +904,12 @@ int RSA_private_transform(RSA *rsa, uint8_t *out, const uint8_t *in,
|
||||
return rsa_default_private_transform(rsa, out, in, len);
|
||||
}
|
||||
|
||||
int rsa_private_transform(RSA *rsa, uint8_t *out, const uint8_t *in,
|
||||
size_t len) {
|
||||
boringssl_ensure_rsa_self_test();
|
||||
return rsa_private_transform_no_self_test(rsa, out, in, len);
|
||||
}
|
||||
|
||||
int RSA_flags(const RSA *rsa) { return rsa->flags; }
|
||||
|
||||
int RSA_test_flags(const RSA *rsa, int flags) { return rsa->flags & flags; }
|
||||
|
@ -266,94 +266,6 @@ size_t rsa_default_size(const RSA *rsa) {
|
||||
return BN_num_bytes(rsa->n);
|
||||
}
|
||||
|
||||
int RSA_encrypt(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
|
||||
const uint8_t *in, size_t in_len, int padding) {
|
||||
boringssl_ensure_rsa_self_test();
|
||||
|
||||
if (!rsa_check_public_key(rsa)) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
const unsigned rsa_size = RSA_size(rsa);
|
||||
BIGNUM *f, *result;
|
||||
uint8_t *buf = NULL;
|
||||
BN_CTX *ctx = NULL;
|
||||
int i, ret = 0;
|
||||
|
||||
if (max_out < rsa_size) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_OUTPUT_BUFFER_TOO_SMALL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
ctx = BN_CTX_new();
|
||||
if (ctx == NULL) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
BN_CTX_start(ctx);
|
||||
f = BN_CTX_get(ctx);
|
||||
result = BN_CTX_get(ctx);
|
||||
buf = OPENSSL_malloc(rsa_size);
|
||||
if (!f || !result || !buf) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
switch (padding) {
|
||||
case RSA_PKCS1_PADDING:
|
||||
i = RSA_padding_add_PKCS1_type_2(buf, rsa_size, in, in_len);
|
||||
break;
|
||||
case RSA_PKCS1_OAEP_PADDING:
|
||||
// Use the default parameters: SHA-1 for both hashes and no label.
|
||||
i = RSA_padding_add_PKCS1_OAEP_mgf1(buf, rsa_size, in, in_len,
|
||||
NULL, 0, NULL, NULL);
|
||||
break;
|
||||
case RSA_NO_PADDING:
|
||||
i = RSA_padding_add_none(buf, rsa_size, in, in_len);
|
||||
break;
|
||||
default:
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_UNKNOWN_PADDING_TYPE);
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (i <= 0) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (BN_bin2bn(buf, rsa_size, f) == NULL) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (BN_ucmp(f, rsa->n) >= 0) {
|
||||
// usually the padding functions would catch this
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (!BN_MONT_CTX_set_locked(&rsa->mont_n, &rsa->lock, rsa->n, ctx) ||
|
||||
!BN_mod_exp_mont(result, f, rsa->e, &rsa->mont_n->N, ctx, rsa->mont_n)) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
// put in leading 0 bytes if the number is less than the length of the
|
||||
// modulus
|
||||
if (!BN_bn2bin_padded(out, rsa_size, result)) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_INTERNAL_ERROR);
|
||||
goto err;
|
||||
}
|
||||
|
||||
*out_len = rsa_size;
|
||||
ret = 1;
|
||||
|
||||
err:
|
||||
if (ctx != NULL) {
|
||||
BN_CTX_end(ctx);
|
||||
BN_CTX_free(ctx);
|
||||
}
|
||||
OPENSSL_free(buf);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
// MAX_BLINDINGS_PER_RSA defines the maximum number of cached BN_BLINDINGs per
|
||||
// RSA*. Then this limit is exceeded, BN_BLINDING objects will be created and
|
||||
// destroyed as needed.
|
||||
@ -516,7 +428,7 @@ int rsa_default_sign_raw(RSA *rsa, size_t *out_len, uint8_t *out,
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (!RSA_private_transform(rsa, out, buf, rsa_size)) {
|
||||
if (!rsa_private_transform_no_self_test(rsa, out, buf, rsa_size)) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
@ -530,71 +442,6 @@ err:
|
||||
return ret;
|
||||
}
|
||||
|
||||
int rsa_default_decrypt(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
|
||||
const uint8_t *in, size_t in_len, int padding) {
|
||||
boringssl_ensure_rsa_self_test();
|
||||
|
||||
const unsigned rsa_size = RSA_size(rsa);
|
||||
uint8_t *buf = NULL;
|
||||
int ret = 0;
|
||||
|
||||
if (max_out < rsa_size) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_OUTPUT_BUFFER_TOO_SMALL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (padding == RSA_NO_PADDING) {
|
||||
buf = out;
|
||||
} else {
|
||||
// Allocate a temporary buffer to hold the padded plaintext.
|
||||
buf = OPENSSL_malloc(rsa_size);
|
||||
if (buf == NULL) {
|
||||
goto err;
|
||||
}
|
||||
}
|
||||
|
||||
if (in_len != rsa_size) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_LEN_NOT_EQUAL_TO_MOD_LEN);
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (!RSA_private_transform(rsa, buf, in, rsa_size)) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
switch (padding) {
|
||||
case RSA_PKCS1_PADDING:
|
||||
ret =
|
||||
RSA_padding_check_PKCS1_type_2(out, out_len, rsa_size, buf, rsa_size);
|
||||
break;
|
||||
case RSA_PKCS1_OAEP_PADDING:
|
||||
// Use the default parameters: SHA-1 for both hashes and no label.
|
||||
ret = RSA_padding_check_PKCS1_OAEP_mgf1(out, out_len, rsa_size, buf,
|
||||
rsa_size, NULL, 0, NULL, NULL);
|
||||
break;
|
||||
case RSA_NO_PADDING:
|
||||
*out_len = rsa_size;
|
||||
ret = 1;
|
||||
break;
|
||||
default:
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_UNKNOWN_PADDING_TYPE);
|
||||
goto err;
|
||||
}
|
||||
|
||||
CONSTTIME_DECLASSIFY(&ret, sizeof(ret));
|
||||
if (!ret) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_PADDING_CHECK_FAILED);
|
||||
} else {
|
||||
CONSTTIME_DECLASSIFY(out, *out_len);
|
||||
}
|
||||
|
||||
err:
|
||||
if (padding != RSA_NO_PADDING) {
|
||||
OPENSSL_free(buf);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int mod_exp(BIGNUM *r0, const BIGNUM *I, RSA *rsa, BN_CTX *ctx);
|
||||
|
||||
|
77
crypto/rsa_extra/internal.h
Normal file
77
crypto/rsa_extra/internal.h
Normal file
@ -0,0 +1,77 @@
|
||||
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
|
||||
* All rights reserved.
|
||||
*
|
||||
* This package is an SSL implementation written
|
||||
* by Eric Young (eay@cryptsoft.com).
|
||||
* The implementation was written so as to conform with Netscapes SSL.
|
||||
*
|
||||
* This library is free for commercial and non-commercial use as long as
|
||||
* the following conditions are aheared to. The following conditions
|
||||
* apply to all code found in this distribution, be it the RC4, RSA,
|
||||
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
|
||||
* included with this distribution is covered by the same copyright terms
|
||||
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
|
||||
*
|
||||
* Copyright remains Eric Young's, and as such any Copyright notices in
|
||||
* the code are not to be removed.
|
||||
* If this package is used in a product, Eric Young should be given attribution
|
||||
* as the author of the parts of the library used.
|
||||
* This can be in the form of a textual message at program startup or
|
||||
* in documentation (online or textual) provided with the package.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
* 1. Redistributions of source code must retain the copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in the
|
||||
* documentation and/or other materials provided with the distribution.
|
||||
* 3. All advertising materials mentioning features or use of this software
|
||||
* must display the following acknowledgement:
|
||||
* "This product includes cryptographic software written by
|
||||
* Eric Young (eay@cryptsoft.com)"
|
||||
* The word 'cryptographic' can be left out if the rouines from the library
|
||||
* being used are not cryptographic related :-).
|
||||
* 4. If you include any Windows specific code (or a derivative thereof) from
|
||||
* the apps directory (application code) you must include an acknowledgement:
|
||||
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
|
||||
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
||||
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||||
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
*
|
||||
* The licence and distribution terms for any publically available version or
|
||||
* derivative of this code cannot be changed. i.e. this code cannot simply be
|
||||
* copied and put under another distribution licence
|
||||
* [including the GNU Public Licence.] */
|
||||
|
||||
|
||||
#ifndef OPENSSL_HEADER_RSA_EXTRA_INTERNAL_H
|
||||
#define OPENSSL_HEADER_RSA_EXTRA_INTERNAL_H
|
||||
|
||||
#if defined(__cplusplus)
|
||||
extern "C" {
|
||||
#endif
|
||||
|
||||
|
||||
int RSA_padding_check_PKCS1_OAEP_mgf1(uint8_t *out, size_t *out_len,
|
||||
size_t max_out, const uint8_t *from,
|
||||
size_t from_len, const uint8_t *param,
|
||||
size_t param_len, const EVP_MD *md,
|
||||
const EVP_MD *mgf1md);
|
||||
|
||||
|
||||
#if defined(__cplusplus)
|
||||
} // extern C
|
||||
#endif
|
||||
|
||||
#endif // OPENSSL_HEADER_RSA_EXTRA_INTERNAL_H
|
563
crypto/rsa_extra/rsa_crypt.c
Normal file
563
crypto/rsa_extra/rsa_crypt.c
Normal file
@ -0,0 +1,563 @@
|
||||
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
|
||||
* All rights reserved.
|
||||
*
|
||||
* This package is an SSL implementation written
|
||||
* by Eric Young (eay@cryptsoft.com).
|
||||
* The implementation was written so as to conform with Netscapes SSL.
|
||||
*
|
||||
* This library is free for commercial and non-commercial use as long as
|
||||
* the following conditions are aheared to. The following conditions
|
||||
* apply to all code found in this distribution, be it the RC4, RSA,
|
||||
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
|
||||
* included with this distribution is covered by the same copyright terms
|
||||
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
|
||||
*
|
||||
* Copyright remains Eric Young's, and as such any Copyright notices in
|
||||
* the code are not to be removed.
|
||||
* If this package is used in a product, Eric Young should be given attribution
|
||||
* as the author of the parts of the library used.
|
||||
* This can be in the form of a textual message at program startup or
|
||||
* in documentation (online or textual) provided with the package.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
* 1. Redistributions of source code must retain the copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in the
|
||||
* documentation and/or other materials provided with the distribution.
|
||||
* 3. All advertising materials mentioning features or use of this software
|
||||
* must display the following acknowledgement:
|
||||
* "This product includes cryptographic software written by
|
||||
* Eric Young (eay@cryptsoft.com)"
|
||||
* The word 'cryptographic' can be left out if the rouines from the library
|
||||
* being used are not cryptographic related :-).
|
||||
* 4. If you include any Windows specific code (or a derivative thereof) from
|
||||
* the apps directory (application code) you must include an acknowledgement:
|
||||
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
|
||||
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||||
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
||||
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||||
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||||
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||||
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||||
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||||
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
*
|
||||
* The licence and distribution terms for any publically available version or
|
||||
* derivative of this code cannot be changed. i.e. this code cannot simply be
|
||||
* copied and put under another distribution licence
|
||||
* [including the GNU Public Licence.] */
|
||||
|
||||
#include <openssl/base.h>
|
||||
|
||||
#include <limits.h>
|
||||
|
||||
#include <openssl/err.h>
|
||||
#include <openssl/rsa.h>
|
||||
#include <openssl/bn.h>
|
||||
#include <openssl/rand.h>
|
||||
#include <openssl/mem.h>
|
||||
#include <openssl/evp.h>
|
||||
|
||||
#include "../fipsmodule/bn/internal.h"
|
||||
#include "../fipsmodule/rsa/internal.h"
|
||||
#include "../internal.h"
|
||||
#include "internal.h"
|
||||
|
||||
|
||||
static void rand_nonzero(uint8_t *out, size_t len) {
|
||||
RAND_bytes(out, len);
|
||||
|
||||
for (size_t i = 0; i < len; i++) {
|
||||
while (out[i] == 0) {
|
||||
RAND_bytes(out + i, 1);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
int RSA_padding_add_PKCS1_OAEP_mgf1(uint8_t *to, size_t to_len,
|
||||
const uint8_t *from, size_t from_len,
|
||||
const uint8_t *param, size_t param_len,
|
||||
const EVP_MD *md, const EVP_MD *mgf1md) {
|
||||
if (md == NULL) {
|
||||
md = EVP_sha1();
|
||||
}
|
||||
if (mgf1md == NULL) {
|
||||
mgf1md = md;
|
||||
}
|
||||
|
||||
size_t mdlen = EVP_MD_size(md);
|
||||
|
||||
if (to_len < 2 * mdlen + 2) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_KEY_SIZE_TOO_SMALL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
size_t emlen = to_len - 1;
|
||||
if (from_len > emlen - 2 * mdlen - 1) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (emlen < 2 * mdlen + 1) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_KEY_SIZE_TOO_SMALL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
to[0] = 0;
|
||||
uint8_t *seed = to + 1;
|
||||
uint8_t *db = to + mdlen + 1;
|
||||
|
||||
uint8_t *dbmask = NULL;
|
||||
int ret = 0;
|
||||
if (!EVP_Digest(param, param_len, db, NULL, md, NULL)) {
|
||||
goto out;
|
||||
}
|
||||
OPENSSL_memset(db + mdlen, 0, emlen - from_len - 2 * mdlen - 1);
|
||||
db[emlen - from_len - mdlen - 1] = 0x01;
|
||||
OPENSSL_memcpy(db + emlen - from_len - mdlen, from, from_len);
|
||||
if (!RAND_bytes(seed, mdlen)) {
|
||||
goto out;
|
||||
}
|
||||
|
||||
dbmask = OPENSSL_malloc(emlen - mdlen);
|
||||
if (dbmask == NULL) {
|
||||
goto out;
|
||||
}
|
||||
|
||||
if (!PKCS1_MGF1(dbmask, emlen - mdlen, seed, mdlen, mgf1md)) {
|
||||
goto out;
|
||||
}
|
||||
for (size_t i = 0; i < emlen - mdlen; i++) {
|
||||
db[i] ^= dbmask[i];
|
||||
}
|
||||
|
||||
uint8_t seedmask[EVP_MAX_MD_SIZE];
|
||||
if (!PKCS1_MGF1(seedmask, mdlen, db, emlen - mdlen, mgf1md)) {
|
||||
goto out;
|
||||
}
|
||||
for (size_t i = 0; i < mdlen; i++) {
|
||||
seed[i] ^= seedmask[i];
|
||||
}
|
||||
ret = 1;
|
||||
|
||||
out:
|
||||
OPENSSL_free(dbmask);
|
||||
return ret;
|
||||
}
|
||||
|
||||
int RSA_padding_check_PKCS1_OAEP_mgf1(uint8_t *out, size_t *out_len,
|
||||
size_t max_out, const uint8_t *from,
|
||||
size_t from_len, const uint8_t *param,
|
||||
size_t param_len, const EVP_MD *md,
|
||||
const EVP_MD *mgf1md) {
|
||||
uint8_t *db = NULL;
|
||||
|
||||
if (md == NULL) {
|
||||
md = EVP_sha1();
|
||||
}
|
||||
if (mgf1md == NULL) {
|
||||
mgf1md = md;
|
||||
}
|
||||
|
||||
size_t mdlen = EVP_MD_size(md);
|
||||
|
||||
// The encoded message is one byte smaller than the modulus to ensure that it
|
||||
// doesn't end up greater than the modulus. Thus there's an extra "+1" here
|
||||
// compared to https://tools.ietf.org/html/rfc2437#section-9.1.1.2.
|
||||
if (from_len < 1 + 2 * mdlen + 1) {
|
||||
// 'from_len' is the length of the modulus, i.e. does not depend on the
|
||||
// particular ciphertext.
|
||||
goto decoding_err;
|
||||
}
|
||||
|
||||
size_t dblen = from_len - mdlen - 1;
|
||||
db = OPENSSL_malloc(dblen);
|
||||
if (db == NULL) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
const uint8_t *maskedseed = from + 1;
|
||||
const uint8_t *maskeddb = from + 1 + mdlen;
|
||||
|
||||
uint8_t seed[EVP_MAX_MD_SIZE];
|
||||
if (!PKCS1_MGF1(seed, mdlen, maskeddb, dblen, mgf1md)) {
|
||||
goto err;
|
||||
}
|
||||
for (size_t i = 0; i < mdlen; i++) {
|
||||
seed[i] ^= maskedseed[i];
|
||||
}
|
||||
|
||||
if (!PKCS1_MGF1(db, dblen, seed, mdlen, mgf1md)) {
|
||||
goto err;
|
||||
}
|
||||
for (size_t i = 0; i < dblen; i++) {
|
||||
db[i] ^= maskeddb[i];
|
||||
}
|
||||
|
||||
uint8_t phash[EVP_MAX_MD_SIZE];
|
||||
if (!EVP_Digest(param, param_len, phash, NULL, md, NULL)) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
crypto_word_t bad = ~constant_time_is_zero_w(CRYPTO_memcmp(db, phash, mdlen));
|
||||
bad |= ~constant_time_is_zero_w(from[0]);
|
||||
|
||||
crypto_word_t looking_for_one_byte = CONSTTIME_TRUE_W;
|
||||
size_t one_index = 0;
|
||||
for (size_t i = mdlen; i < dblen; i++) {
|
||||
crypto_word_t equals1 = constant_time_eq_w(db[i], 1);
|
||||
crypto_word_t equals0 = constant_time_eq_w(db[i], 0);
|
||||
one_index =
|
||||
constant_time_select_w(looking_for_one_byte & equals1, i, one_index);
|
||||
looking_for_one_byte =
|
||||
constant_time_select_w(equals1, 0, looking_for_one_byte);
|
||||
bad |= looking_for_one_byte & ~equals0;
|
||||
}
|
||||
|
||||
bad |= looking_for_one_byte;
|
||||
|
||||
// Whether the overall padding was valid or not in OAEP is public.
|
||||
if (constant_time_declassify_w(bad)) {
|
||||
goto decoding_err;
|
||||
}
|
||||
|
||||
// Once the padding is known to be valid, the output length is also public.
|
||||
static_assert(sizeof(size_t) <= sizeof(crypto_word_t),
|
||||
"size_t does not fit in crypto_word_t");
|
||||
one_index = constant_time_declassify_w(one_index);
|
||||
|
||||
one_index++;
|
||||
size_t mlen = dblen - one_index;
|
||||
if (max_out < mlen) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE);
|
||||
goto err;
|
||||
}
|
||||
|
||||
OPENSSL_memcpy(out, db + one_index, mlen);
|
||||
*out_len = mlen;
|
||||
OPENSSL_free(db);
|
||||
return 1;
|
||||
|
||||
decoding_err:
|
||||
// To avoid chosen ciphertext attacks, the error message should not reveal
|
||||
// which kind of decoding error happened.
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_OAEP_DECODING_ERROR);
|
||||
err:
|
||||
OPENSSL_free(db);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int rsa_padding_add_PKCS1_type_2(uint8_t *to, size_t to_len,
|
||||
const uint8_t *from, size_t from_len) {
|
||||
// See RFC 8017, section 7.2.1.
|
||||
if (to_len < RSA_PKCS1_PADDING_SIZE) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_KEY_SIZE_TOO_SMALL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (from_len > to_len - RSA_PKCS1_PADDING_SIZE) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
|
||||
return 0;
|
||||
}
|
||||
|
||||
to[0] = 0;
|
||||
to[1] = 2;
|
||||
|
||||
size_t padding_len = to_len - 3 - from_len;
|
||||
rand_nonzero(to + 2, padding_len);
|
||||
to[2 + padding_len] = 0;
|
||||
OPENSSL_memcpy(to + to_len - from_len, from, from_len);
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int rsa_padding_check_PKCS1_type_2(uint8_t *out, size_t *out_len,
|
||||
size_t max_out, const uint8_t *from,
|
||||
size_t from_len) {
|
||||
if (from_len == 0) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_EMPTY_PUBLIC_KEY);
|
||||
return 0;
|
||||
}
|
||||
|
||||
// PKCS#1 v1.5 decryption. See "PKCS #1 v2.2: RSA Cryptography
|
||||
// Standard", section 7.2.2.
|
||||
if (from_len < RSA_PKCS1_PADDING_SIZE) {
|
||||
// |from| is zero-padded to the size of the RSA modulus, a public value, so
|
||||
// this can be rejected in non-constant time.
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_KEY_SIZE_TOO_SMALL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
crypto_word_t first_byte_is_zero = constant_time_eq_w(from[0], 0);
|
||||
crypto_word_t second_byte_is_two = constant_time_eq_w(from[1], 2);
|
||||
|
||||
crypto_word_t zero_index = 0, looking_for_index = CONSTTIME_TRUE_W;
|
||||
for (size_t i = 2; i < from_len; i++) {
|
||||
crypto_word_t equals0 = constant_time_is_zero_w(from[i]);
|
||||
zero_index =
|
||||
constant_time_select_w(looking_for_index & equals0, i, zero_index);
|
||||
looking_for_index = constant_time_select_w(equals0, 0, looking_for_index);
|
||||
}
|
||||
|
||||
// The input must begin with 00 02.
|
||||
crypto_word_t valid_index = first_byte_is_zero;
|
||||
valid_index &= second_byte_is_two;
|
||||
|
||||
// We must have found the end of PS.
|
||||
valid_index &= ~looking_for_index;
|
||||
|
||||
// PS must be at least 8 bytes long, and it starts two bytes into |from|.
|
||||
valid_index &= constant_time_ge_w(zero_index, 2 + 8);
|
||||
|
||||
// Skip the zero byte.
|
||||
zero_index++;
|
||||
|
||||
// NOTE: Although this logic attempts to be constant time, the API contracts
|
||||
// of this function and |RSA_decrypt| with |RSA_PKCS1_PADDING| make it
|
||||
// impossible to completely avoid Bleichenbacher's attack. Consumers should
|
||||
// use |RSA_PADDING_NONE| and perform the padding check in constant-time
|
||||
// combined with a swap to a random session key or other mitigation.
|
||||
CONSTTIME_DECLASSIFY(&valid_index, sizeof(valid_index));
|
||||
CONSTTIME_DECLASSIFY(&zero_index, sizeof(zero_index));
|
||||
|
||||
if (!valid_index) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_PKCS_DECODING_ERROR);
|
||||
return 0;
|
||||
}
|
||||
|
||||
const size_t msg_len = from_len - zero_index;
|
||||
if (msg_len > max_out) {
|
||||
// This shouldn't happen because this function is always called with
|
||||
// |max_out| as the key size and |from_len| is bounded by the key size.
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_PKCS_DECODING_ERROR);
|
||||
return 0;
|
||||
}
|
||||
|
||||
OPENSSL_memcpy(out, &from[zero_index], msg_len);
|
||||
*out_len = msg_len;
|
||||
return 1;
|
||||
}
|
||||
|
||||
int RSA_public_encrypt(size_t flen, const uint8_t *from, uint8_t *to, RSA *rsa,
|
||||
int padding) {
|
||||
size_t out_len;
|
||||
|
||||
if (!RSA_encrypt(rsa, &out_len, to, RSA_size(rsa), from, flen, padding)) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (out_len > INT_MAX) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
|
||||
return -1;
|
||||
}
|
||||
return (int)out_len;
|
||||
}
|
||||
|
||||
int RSA_private_encrypt(size_t flen, const uint8_t *from, uint8_t *to, RSA *rsa,
|
||||
int padding) {
|
||||
size_t out_len;
|
||||
|
||||
if (!RSA_sign_raw(rsa, &out_len, to, RSA_size(rsa), from, flen, padding)) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (out_len > INT_MAX) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
|
||||
return -1;
|
||||
}
|
||||
return (int)out_len;
|
||||
}
|
||||
|
||||
int RSA_encrypt(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
|
||||
const uint8_t *in, size_t in_len, int padding) {
|
||||
if (!rsa_check_public_key(rsa)) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
const unsigned rsa_size = RSA_size(rsa);
|
||||
BIGNUM *f, *result;
|
||||
uint8_t *buf = NULL;
|
||||
BN_CTX *ctx = NULL;
|
||||
int i, ret = 0;
|
||||
|
||||
if (max_out < rsa_size) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_OUTPUT_BUFFER_TOO_SMALL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
ctx = BN_CTX_new();
|
||||
if (ctx == NULL) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
BN_CTX_start(ctx);
|
||||
f = BN_CTX_get(ctx);
|
||||
result = BN_CTX_get(ctx);
|
||||
buf = OPENSSL_malloc(rsa_size);
|
||||
if (!f || !result || !buf) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
switch (padding) {
|
||||
case RSA_PKCS1_PADDING:
|
||||
i = rsa_padding_add_PKCS1_type_2(buf, rsa_size, in, in_len);
|
||||
break;
|
||||
case RSA_PKCS1_OAEP_PADDING:
|
||||
// Use the default parameters: SHA-1 for both hashes and no label.
|
||||
i = RSA_padding_add_PKCS1_OAEP_mgf1(buf, rsa_size, in, in_len, NULL, 0,
|
||||
NULL, NULL);
|
||||
break;
|
||||
case RSA_NO_PADDING:
|
||||
i = RSA_padding_add_none(buf, rsa_size, in, in_len);
|
||||
break;
|
||||
default:
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_UNKNOWN_PADDING_TYPE);
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (i <= 0) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (BN_bin2bn(buf, rsa_size, f) == NULL) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (BN_ucmp(f, rsa->n) >= 0) {
|
||||
// usually the padding functions would catch this
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_TOO_LARGE_FOR_MODULUS);
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (!BN_MONT_CTX_set_locked(&rsa->mont_n, &rsa->lock, rsa->n, ctx) ||
|
||||
!BN_mod_exp_mont(result, f, rsa->e, &rsa->mont_n->N, ctx, rsa->mont_n)) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
// put in leading 0 bytes if the number is less than the length of the
|
||||
// modulus
|
||||
if (!BN_bn2bin_padded(out, rsa_size, result)) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_INTERNAL_ERROR);
|
||||
goto err;
|
||||
}
|
||||
|
||||
*out_len = rsa_size;
|
||||
ret = 1;
|
||||
|
||||
err:
|
||||
if (ctx != NULL) {
|
||||
BN_CTX_end(ctx);
|
||||
BN_CTX_free(ctx);
|
||||
}
|
||||
OPENSSL_free(buf);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int rsa_default_decrypt(RSA *rsa, size_t *out_len, uint8_t *out,
|
||||
size_t max_out, const uint8_t *in, size_t in_len,
|
||||
int padding) {
|
||||
const unsigned rsa_size = RSA_size(rsa);
|
||||
uint8_t *buf = NULL;
|
||||
int ret = 0;
|
||||
|
||||
if (max_out < rsa_size) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_OUTPUT_BUFFER_TOO_SMALL);
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (padding == RSA_NO_PADDING) {
|
||||
buf = out;
|
||||
} else {
|
||||
// Allocate a temporary buffer to hold the padded plaintext.
|
||||
buf = OPENSSL_malloc(rsa_size);
|
||||
if (buf == NULL) {
|
||||
goto err;
|
||||
}
|
||||
}
|
||||
|
||||
if (in_len != rsa_size) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_DATA_LEN_NOT_EQUAL_TO_MOD_LEN);
|
||||
goto err;
|
||||
}
|
||||
|
||||
if (!rsa_private_transform(rsa, buf, in, rsa_size)) {
|
||||
goto err;
|
||||
}
|
||||
|
||||
switch (padding) {
|
||||
case RSA_PKCS1_PADDING:
|
||||
ret =
|
||||
rsa_padding_check_PKCS1_type_2(out, out_len, rsa_size, buf, rsa_size);
|
||||
break;
|
||||
case RSA_PKCS1_OAEP_PADDING:
|
||||
// Use the default parameters: SHA-1 for both hashes and no label.
|
||||
ret = RSA_padding_check_PKCS1_OAEP_mgf1(out, out_len, rsa_size, buf,
|
||||
rsa_size, NULL, 0, NULL, NULL);
|
||||
break;
|
||||
case RSA_NO_PADDING:
|
||||
*out_len = rsa_size;
|
||||
ret = 1;
|
||||
break;
|
||||
default:
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_UNKNOWN_PADDING_TYPE);
|
||||
goto err;
|
||||
}
|
||||
|
||||
CONSTTIME_DECLASSIFY(&ret, sizeof(ret));
|
||||
if (!ret) {
|
||||
OPENSSL_PUT_ERROR(RSA, RSA_R_PADDING_CHECK_FAILED);
|
||||
} else {
|
||||
CONSTTIME_DECLASSIFY(out, *out_len);
|
||||
}
|
||||
|
||||
err:
|
||||
if (padding != RSA_NO_PADDING) {
|
||||
OPENSSL_free(buf);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
int RSA_decrypt(RSA *rsa, size_t *out_len, uint8_t *out, size_t max_out,
|
||||
const uint8_t *in, size_t in_len, int padding) {
|
||||
if (rsa->meth->decrypt) {
|
||||
return rsa->meth->decrypt(rsa, out_len, out, max_out, in, in_len, padding);
|
||||
}
|
||||
|
||||
return rsa_default_decrypt(rsa, out_len, out, max_out, in, in_len, padding);
|
||||
}
|
||||
|
||||
int RSA_private_decrypt(size_t flen, const uint8_t *from, uint8_t *to, RSA *rsa,
|
||||
int padding) {
|
||||
size_t out_len;
|
||||
if (!RSA_decrypt(rsa, &out_len, to, RSA_size(rsa), from, flen, padding)) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (out_len > INT_MAX) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
|
||||
return -1;
|
||||
}
|
||||
return (int)out_len;
|
||||
}
|
||||
|
||||
int RSA_public_decrypt(size_t flen, const uint8_t *from, uint8_t *to, RSA *rsa,
|
||||
int padding) {
|
||||
size_t out_len;
|
||||
if (!RSA_verify_raw(rsa, &out_len, to, RSA_size(rsa), from, flen, padding)) {
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (out_len > INT_MAX) {
|
||||
OPENSSL_PUT_ERROR(RSA, ERR_R_OVERFLOW);
|
||||
return -1;
|
||||
}
|
||||
return (int)out_len;
|
||||
}
|
Loading…
x
Reference in New Issue
Block a user