Remove RSA SSLv23 padding mode

Reviewed-by: Kurt Roeckx <kurt@roeckx.be>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/14248)

6 files changed, 1 insertions, 207 deletions

diff --git a/crypto/evp/ctrl_params_translate.c b/crypto/evp/ctrl_params_translate.c
index e0f849d236..ae3340395d 100644
--- a/crypto/evp/ctrl_params_translate.c
+++ b/crypto/evp/ctrl_params_translate.c
@@ -1186,7 +1186,6 @@ static int fix_rsa_padding_mode(enum state state,
 {
     static const OSSL_ITEM str_value_map[] = {
         { RSA_PKCS1_PADDING,            "pkcs1"  },
-        { RSA_SSLV23_PADDING,           "sslv23" },
         { RSA_NO_PADDING,               "none"   },
         { RSA_PKCS1_OAEP_PADDING,       "oaep"   },
         { RSA_PKCS1_OAEP_PADDING,       "oeap"   },
diff --git a/crypto/rsa/build.info b/crypto/rsa/build.info
index f0c7668bf2..ad3370db39 100644
--- a/crypto/rsa/build.info
+++ b/crypto/rsa/build.info
@@ -7,7 +7,7 @@ $COMMON=rsa_ossl.c rsa_gen.c rsa_lib.c rsa_sign.c rsa_pk1.c \
 
 SOURCE[../../libcrypto]=$COMMON\
         rsa_saos.c rsa_err.c rsa_asn1.c rsa_ameth.c rsa_prn.c \
-        rsa_pmeth.c rsa_meth.c rsa_mp.c rsa_ssl.c
+        rsa_pmeth.c rsa_meth.c rsa_mp.c
 IF[{- !$disabled{'deprecated-0.9.8'} -}]
   SOURCE[../../libcrypto]=rsa_depr.c
 ENDIF
diff --git a/crypto/rsa/rsa_local.h b/crypto/rsa/rsa_local.h
index 49a0071031..6d3bc05c14 100644
--- a/crypto/rsa/rsa_local.h
+++ b/crypto/rsa/rsa_local.h
@@ -195,9 +195,6 @@ int ossl_rsa_fips186_4_gen_prob_primes(RSA *rsa, RSA_ACVP_TEST *test,
                                        int nbits, const BIGNUM *e, BN_CTX *ctx,
                                        BN_GENCB *cb);
 
-int ossl_rsa_padding_add_SSLv23_ex(OSSL_LIB_CTX *libctx, unsigned char *to,
-                                   int tlen, const unsigned char *from,
-                                   int flen);
 int ossl_rsa_padding_add_PKCS1_type_2_ex(OSSL_LIB_CTX *libctx, unsigned char *to,
                                          int tlen, const unsigned char *from,
                                          int flen);
diff --git a/crypto/rsa/rsa_ossl.c b/crypto/rsa/rsa_ossl.c
index 7964244ab5..1fd0057202 100644
--- a/crypto/rsa/rsa_ossl.c
+++ b/crypto/rsa/rsa_ossl.c
@@ -119,11 +119,6 @@ static int rsa_ossl_public_encrypt(int flen, const unsigned char *from,
                                                     from, flen, NULL, 0,
                                                     NULL, NULL);
         break;
-#ifndef FIPS_MODULE
-    case RSA_SSLV23_PADDING:
-        i = ossl_rsa_padding_add_SSLv23_ex(rsa->libctx, buf, num, from, flen);
-        break;
-#endif
     case RSA_NO_PADDING:
         i = RSA_padding_add_none(buf, num, from, flen);
         break;
@@ -278,7 +273,6 @@ static int rsa_ossl_private_encrypt(int flen, const unsigned char *from,
     case RSA_NO_PADDING:
         i = RSA_padding_add_none(buf, num, from, flen);
         break;
-    case RSA_SSLV23_PADDING:
     default:
         ERR_raise(ERR_LIB_RSA, RSA_R_UNKNOWN_PADDING_TYPE);
         goto err;
@@ -487,11 +481,6 @@ static int rsa_ossl_private_decrypt(int flen, const unsigned char *from,
     case RSA_PKCS1_OAEP_PADDING:
         r = RSA_padding_check_PKCS1_OAEP(to, num, buf, j, num, NULL, 0);
         break;
-#ifndef FIPS_MODULE
-    case RSA_SSLV23_PADDING:
-        r = RSA_padding_check_SSLv23(to, num, buf, j, num);
-        break;
-#endif
     case RSA_NO_PADDING:
         memcpy(to, buf, (r = j));
         break;
diff --git a/crypto/rsa/rsa_pmeth.c b/crypto/rsa/rsa_pmeth.c
index fc2799af7c..def5641682 100644
--- a/crypto/rsa/rsa_pmeth.c
+++ b/crypto/rsa/rsa_pmeth.c
@@ -604,8 +604,6 @@ static int pkey_rsa_ctrl_str(EVP_PKEY_CTX *ctx,
 
         if (strcmp(value, "pkcs1") == 0) {
             pm = RSA_PKCS1_PADDING;
-        } else if (strcmp(value, "sslv23") == 0) {
-            pm = RSA_SSLV23_PADDING;
         } else if (strcmp(value, "none") == 0) {
             pm = RSA_NO_PADDING;
         } else if (strcmp(value, "oeap") == 0) {
diff --git a/crypto/rsa/rsa_ssl.c b/crypto/rsa/rsa_ssl.c
deleted file mode 100644
index 7cb743d219..0000000000
--- a/crypto/rsa/rsa_ssl.c
+++ /dev/null
@@ -1,189 +0,0 @@
-/*
- * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
- *
- * Licensed under the Apache License 2.0 (the "License").  You may not use
- * this file except in compliance with the License.  You can obtain a copy
- * in the file LICENSE in the source distribution or at
- * https://www.openssl.org/source/license.html
- */
-
-/*
- * RSA low level APIs are deprecated for public use, but still ok for
- * internal use.
- */
-#include "internal/deprecated.h"
-
-#include <stdio.h>
-#include "internal/cryptlib.h"
-#include <openssl/bn.h>
-#include <openssl/rsa.h>
-#include <openssl/rand.h>
-#include "internal/constant_time.h"
-#include "rsa_local.h"
-
-int ossl_rsa_padding_add_SSLv23_ex(OSSL_LIB_CTX *libctx, unsigned char *to,
-                                   int tlen, const unsigned char *from,
-                                   int flen)
-{
-    int i, j;
-    unsigned char *p;
-
-    if (flen > (tlen - RSA_PKCS1_PADDING_SIZE)) {
-        ERR_raise(ERR_LIB_RSA, RSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE);
-        return 0;
-    }
-
-    p = (unsigned char *)to;
-
-    *(p++) = 0;
-    *(p++) = 2;                 /* Public Key BT (Block Type) */
-
-    /* pad out with non-zero random data */
-    j = tlen - 3 - 8 - flen;
-
-    if (RAND_bytes_ex(libctx, p, j) <= 0)
-        return 0;
-    for (i = 0; i < j; i++) {
-        if (*p == '\0')
-            do {
-                if (RAND_bytes_ex(libctx, p, 1) <= 0)
-                    return 0;
-            } while (*p == '\0');
-        p++;
-    }
-
-    memset(p, 3, 8);
-    p += 8;
-    *(p++) = '\0';
-
-    memcpy(p, from, (unsigned int)flen);
-    return 1;
-}
-
-int RSA_padding_add_SSLv23(unsigned char *to, int tlen,
-                           const unsigned char *from, int flen)
-{
-    return ossl_rsa_padding_add_SSLv23_ex(NULL, to, tlen, from, flen);
-}
-
-/*
- * 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
- * preserves error code reporting for backward compatibility.
- */
-int RSA_padding_check_SSLv23(unsigned char *to, int tlen,
-                             const unsigned char *from, int flen, int num)
-{
-    int i;
-    /* |em| is the encoded message, zero-padded to exactly |num| bytes */
-    unsigned char *em = NULL;
-    unsigned int good, found_zero_byte, mask, threes_in_row;
-    int zero_index = 0, msg_index, mlen = -1, err;
-
-    if (tlen <= 0 || flen <= 0)
-        return -1;
-
-    if (flen > num || num < RSA_PKCS1_PADDING_SIZE) {
-        ERR_raise(ERR_LIB_RSA, RSA_R_DATA_TOO_SMALL);
-        return -1;
-    }
-
-    em = OPENSSL_malloc(num);
-    if (em == NULL) {
-        ERR_raise(ERR_LIB_RSA, ERR_R_MALLOC_FAILURE);
-        return -1;
-    }
-    /*
-     * Caller is encouraged to pass zero-padded message created with
-     * BN_bn2binpad. Trouble is that since we can't read out of |from|'s
-     * bounds, it's impossible to have an invariant memory access pattern
-     * in case |from| was not zero-padded in advance.
-     */
-    for (from += flen, em += num, i = 0; i < num; i++) {
-        mask = ~constant_time_is_zero(flen);
-        flen -= 1 & mask;
-        from -= 1 & mask;
-        *--em = *from & mask;
-    }
-
-    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;
-
-    /* scan over padding data */
-    found_zero_byte = 0;
-    threes_in_row = 0;
-    for (i = 2; i < num; 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(em[i], 3);
-    }
-
-    /*
-     * 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.
-     */
-    good &= constant_time_ge(zero_index, 2 + 8);
-    err = constant_time_select_int(mask | good, err,
-                                   RSA_R_NULL_BEFORE_BLOCK_MISSING);
-    mask = ~good;
-
-    /*
-     * Reject if nul delimiter is preceded by 8 consecutive 0x03 bytes. Note
-     * that RFC5246 incorrectly states this the other way around, i.e. reject
-     * if it is not preceded by 8 consecutive 0x03 bytes. However this is
-     * corrected in subsequent errata for that RFC.
-     */
-    good &= constant_time_lt(threes_in_row, 8);
-    err = constant_time_select_int(mask | good, err,
-                                   RSA_R_SSLV3_ROLLBACK_ATTACK);
-    mask = ~good;
-
-    /*
-     * Skip the zero byte. This is incorrect if we never found a zero-byte
-     * but in this case we also do not copy the message out.
-     */
-    msg_index = zero_index + 1;
-    mlen = num - msg_index;
-
-    /*
-     * For good measure, do this check in constant time as well.
-     */
-    good &= constant_time_ge(tlen, mlen);
-    err = constant_time_select_int(mask | good, err, RSA_R_DATA_TOO_LARGE);
-
-    /*
-     * Move the result in-place by |num|-RSA_PKCS1_PADDING_SIZE-|mlen| bytes to the left.
-     * Then if |good| move |mlen| bytes from |em|+RSA_PKCS1_PADDING_SIZE 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 - RSA_PKCS1_PADDING_SIZE, tlen),
-                                    num - RSA_PKCS1_PADDING_SIZE, tlen);
-    for (msg_index = 1; msg_index < num - RSA_PKCS1_PADDING_SIZE; msg_index <<= 1) {
-        mask = ~constant_time_eq(msg_index & (num - RSA_PKCS1_PADDING_SIZE - mlen), 0);
-        for (i = RSA_PKCS1_PADDING_SIZE; 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 + RSA_PKCS1_PADDING_SIZE], to[i]);
-    }
-
-    OPENSSL_clear_free(em, num);
-    ERR_raise(ERR_LIB_RSA, err);
-    err_clear_last_constant_time(1 & good);
-
-    return constant_time_select_int(good, mlen, -1);
-}