Thread-safety fixes

[openssl.git] / crypto / rsa / rsa_eay.c

diff --git a/crypto/rsa/rsa_eay.c b/crypto/rsa/rsa_eay.c
index 6954f36d5d431da70577c11f6c0f51761e811712..69cabd2716445bb1a88b2ef0273b6d498b8ecc41 100644 (file)
--- a/crypto/rsa/rsa_eay.c
+++ b/crypto/rsa/rsa_eay.c
@@ -56,7 +56,7 @@
  * [including the GNU Public Licence.]
  */
 /* ====================================================================
- * Copyright (c) 1998-2005 The OpenSSL Project.  All rights reserved.
+ * Copyright (c) 1998-2006 The OpenSSL Project.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -238,40 +238,63 @@ err:
        return(r);
        }
 
-static BN_BLINDING *rsa_get_blinding(RSA *rsa, BIGNUM **r, int *local, BN_CTX *ctx)
+static BN_BLINDING *rsa_get_blinding(RSA *rsa, int *local, BN_CTX *ctx)
 {
        BN_BLINDING *ret;
+       int got_write_lock = 0;
+
+       CRYPTO_r_lock(CRYPTO_LOCK_RSA);
 
        if (rsa->blinding == NULL)
                {
+               CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
+               CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+               got_write_lock = 1;
+
                if (rsa->blinding == NULL)
-                       {
-                       CRYPTO_w_lock(CRYPTO_LOCK_RSA);
-                       if (rsa->blinding == NULL)
-                               rsa->blinding = RSA_setup_blinding(rsa, ctx);
-                       CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
-                       }
+                       rsa->blinding = RSA_setup_blinding(rsa, ctx);
                }
 
        ret = rsa->blinding;
        if (ret == NULL)
-               return NULL;
+               goto err;
 
-       if (BN_BLINDING_get_thread_id(ret) != CRYPTO_thread_id())
+       if (BN_BLINDING_get_thread_id(ret) == CRYPTO_thread_id())
+               {
+               /* rsa->blinding is ours! */
+
+               *local = 1;
+               }
+       else
                {
-               *local = 0;
+               /* resort to rsa->mt_blinding instead */
+
+               *local = 0; /* instructs rsa_blinding_convert(), rsa_blinding_invert()
+                            * that the BN_BLINDING is shared, meaning that accesses
+                            * require locks, and that the blinding factor must be
+                            * stored outside the BN_BLINDING
+                            */
+
                if (rsa->mt_blinding == NULL)
                        {
-                       CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+                       if (!got_write_lock)
+                               {
+                               CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
+                               CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+                               got_write_lock = 1;
+                               }
+                       
                        if (rsa->mt_blinding == NULL)
                                rsa->mt_blinding = RSA_setup_blinding(rsa, ctx);
-                       CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
                        }
                ret = rsa->mt_blinding;
                }
-       else
-               *local = 1;
 
+ err:
+       if (got_write_lock)
+               CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
+       else
+               CRYPTO_r_unlock(CRYPTO_LOCK_RSA);
        return ret;
 }
 
@@ -283,9 +306,9 @@ static int rsa_blinding_convert(BN_BLINDING *b, int local, BIGNUM *f,
        else
                {
                int ret;
-               CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
+               CRYPTO_r_lock(CRYPTO_LOCK_RSA_BLINDING);
                ret = BN_BLINDING_convert_ex(f, r, b, ctx);
-               CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
+               CRYPTO_r_unlock(CRYPTO_LOCK_RSA_BLINDING);
                return ret;
                }
 }
@@ -298,9 +321,9 @@ static int rsa_blinding_invert(BN_BLINDING *b, int local, BIGNUM *f,
        else
                {
                int ret;
-               CRYPTO_r_lock(CRYPTO_LOCK_RSA_BLINDING);
+               CRYPTO_w_lock(CRYPTO_LOCK_RSA_BLINDING);
                ret = BN_BLINDING_invert_ex(f, r, b, ctx);
-               CRYPTO_r_unlock(CRYPTO_LOCK_RSA_BLINDING);
+               CRYPTO_w_unlock(CRYPTO_LOCK_RSA_BLINDING);
                return ret;
                }
 }
@@ -309,7 +332,7 @@ static int rsa_blinding_invert(BN_BLINDING *b, int local, BIGNUM *f,
 static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
             unsigned char *to, RSA *rsa, int padding)
        {
-       BIGNUM *f, *ret, *br;
+       BIGNUM *f, *ret, *br, *res;
        int i,j,k,num=0,r= -1;
        unsigned char *buf=NULL;
        BN_CTX *ctx=NULL;
@@ -334,6 +357,9 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
        case RSA_PKCS1_PADDING:
                i=RSA_padding_add_PKCS1_type_1(buf,num,from,flen);
                break;
+       case RSA_X931_PADDING:
+               i=RSA_padding_add_X931(buf,num,from,flen);
+               break;
        case RSA_NO_PADDING:
                i=RSA_padding_add_none(buf,num,from,flen);
                break;
@@ -355,7 +381,7 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
 
        if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
                {
-               blinding = rsa_get_blinding(rsa, &br, &local_blinding, ctx);
+               blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
                if (blinding == NULL)
                        {
                        RSAerr(RSA_F_RSA_EAY_PRIVATE_ENCRYPT, ERR_R_INTERNAL_ERROR);
@@ -400,10 +426,21 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
                if (!rsa_blinding_invert(blinding, local_blinding, ret, br, ctx))
                        goto err;
 
+       if (padding == RSA_X931_PADDING)
+               {
+               BN_sub(f, rsa->n, ret);
+               if (BN_cmp(ret, f))
+                       res = f;
+               else
+                       res = ret;
+               }
+       else
+               res = ret;
+
        /* put in leading 0 bytes if the number is less than the
         * length of the modulus */
-       j=BN_num_bytes(ret);
-       i=BN_bn2bin(ret,&(to[num-j]));
+       j=BN_num_bytes(res);
+       i=BN_bn2bin(res,&(to[num-j]));
        for (k=0; k<(num-i); k++)
                to[k]=0;
 
@@ -465,7 +502,7 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
 
        if (!(rsa->flags & RSA_FLAG_NO_BLINDING))
                {
-               blinding = rsa_get_blinding(rsa, &br, &local_blinding, ctx);
+               blinding = rsa_get_blinding(rsa, &local_blinding, ctx);
                if (blinding == NULL)
                        {
                        RSAerr(RSA_F_RSA_EAY_PRIVATE_DECRYPT, ERR_R_INTERNAL_ERROR);
@@ -593,6 +630,9 @@ static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
        if (!rsa->meth->bn_mod_exp(ret,f,rsa->e,rsa->n,ctx,
                rsa->_method_mod_n)) goto err;
 
+       if ((padding == RSA_X931_PADDING) && ((ret->d[0] & 0xf) != 12))
+               BN_sub(ret, rsa->n, ret);
+
        p=buf;
        i=BN_bn2bin(ret,p);
 
@@ -601,6 +641,9 @@ static int RSA_eay_public_decrypt(int flen, const unsigned char *from,
        case RSA_PKCS1_PADDING:
                r=RSA_padding_check_PKCS1_type_1(to,num,buf,i,num);
                break;
+       case RSA_X931_PADDING:
+               r=RSA_padding_check_X931(to,num,buf,i,num);
+               break;
        case RSA_NO_PADDING:
                r=RSA_padding_check_none(to,num,buf,i,num);
                break;