Enforce blinding on RSA operations involving private keys.

From http://www.openssl.org/~geoff, modified to be enabled at all times.

4 files changed, 54 insertions, 8 deletions

diff --git a/src/lib/libcrypto/rsa/rsa_eay.c b/src/lib/libcrypto/rsa/rsa_eay.c
index 0eda816081..3fe1cd6540 100644
--- a/src/lib/libcrypto/rsa/rsa_eay.c
+++ b/src/lib/libcrypto/rsa/rsa_eay.c
@@ -97,6 +97,21 @@ const RSA_METHOD *RSA_PKCS1_SSLeay(void)
         return(&rsa_pkcs1_eay_meth);
         }
 
+static void rsa_eay_blinding(RSA *rsa, BN_CTX *ctx)
+        {
+        CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+        /* Check again inside the lock - the macro's check is racey */
+        if(rsa->blinding == NULL)
+                RSA_blinding_on(rsa, ctx);
+        CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
+        }
+#define BLINDING_HELPER(rsa, ctx) \
+        do { \
+                if(((rsa)->flags & RSA_FLAG_BLINDING) && \
+                                ((rsa)->blinding == NULL)) \
+                        rsa_eay_blinding(rsa, ctx); \
+        } while(0)
+
 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
              unsigned char *to, RSA *rsa, int padding)
         {
@@ -237,8 +252,8 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
                 goto err;
                 }
 
-        if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
-                RSA_blinding_on(rsa,ctx);
+        BLINDING_HELPER(rsa, ctx);
+
         if (rsa->flags & RSA_FLAG_BLINDING)
                 if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
 
@@ -316,8 +331,8 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
                 goto err;
                 }
 
-        if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
-                RSA_blinding_on(rsa,ctx);
+        BLINDING_HELPER(rsa, ctx);
+
         if (rsa->flags & RSA_FLAG_BLINDING)
                 if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
 
@@ -592,6 +607,10 @@ err:
 static int RSA_eay_init(RSA *rsa)
         {
         rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
+
+        /* Enforce blinding. */
+        rsa->flags|=RSA_FLAG_BLINDING;
+
         return(1);
         }
 
diff --git a/src/lib/libcrypto/rsa/rsa_lib.c b/src/lib/libcrypto/rsa/rsa_lib.c
index 93235744f7..f71870a338 100644
--- a/src/lib/libcrypto/rsa/rsa_lib.c
+++ b/src/lib/libcrypto/rsa/rsa_lib.c
@@ -181,6 +181,10 @@ RSA *RSA_new_method(ENGINE *engine)
                 OPENSSL_free(ret);
                 ret=NULL;
                 }
+
+        /* Enforce blinding. */
+        ret->flags |= RSA_FLAG_BLINDING;
+
         return(ret);
         }
 
diff --git a/src/lib/libssl/src/crypto/rsa/rsa_eay.c b/src/lib/libssl/src/crypto/rsa/rsa_eay.c
index 0eda816081..3fe1cd6540 100644
--- a/src/lib/libssl/src/crypto/rsa/rsa_eay.c
+++ b/src/lib/libssl/src/crypto/rsa/rsa_eay.c
@@ -97,6 +97,21 @@ const RSA_METHOD *RSA_PKCS1_SSLeay(void)
         return(&rsa_pkcs1_eay_meth);
         }
 
+static void rsa_eay_blinding(RSA *rsa, BN_CTX *ctx)
+        {
+        CRYPTO_w_lock(CRYPTO_LOCK_RSA);
+        /* Check again inside the lock - the macro's check is racey */
+        if(rsa->blinding == NULL)
+                RSA_blinding_on(rsa, ctx);
+        CRYPTO_w_unlock(CRYPTO_LOCK_RSA);
+        }
+#define BLINDING_HELPER(rsa, ctx) \
+        do { \
+                if(((rsa)->flags & RSA_FLAG_BLINDING) && \
+                                ((rsa)->blinding == NULL)) \
+                        rsa_eay_blinding(rsa, ctx); \
+        } while(0)
+
 static int RSA_eay_public_encrypt(int flen, const unsigned char *from,
              unsigned char *to, RSA *rsa, int padding)
         {
@@ -237,8 +252,8 @@ static int RSA_eay_private_encrypt(int flen, const unsigned char *from,
                 goto err;
                 }
 
-        if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
-                RSA_blinding_on(rsa,ctx);
+        BLINDING_HELPER(rsa, ctx);
+
         if (rsa->flags & RSA_FLAG_BLINDING)
                 if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
 
@@ -316,8 +331,8 @@ static int RSA_eay_private_decrypt(int flen, const unsigned char *from,
                 goto err;
                 }
 
-        if ((rsa->flags & RSA_FLAG_BLINDING) && (rsa->blinding == NULL))
-                RSA_blinding_on(rsa,ctx);
+        BLINDING_HELPER(rsa, ctx);
+
         if (rsa->flags & RSA_FLAG_BLINDING)
                 if (!BN_BLINDING_convert(&f,rsa->blinding,ctx)) goto err;
 
@@ -592,6 +607,10 @@ err:
 static int RSA_eay_init(RSA *rsa)
         {
         rsa->flags|=RSA_FLAG_CACHE_PUBLIC|RSA_FLAG_CACHE_PRIVATE;
+
+        /* Enforce blinding. */
+        rsa->flags|=RSA_FLAG_BLINDING;
+
         return(1);
         }
 
diff --git a/src/lib/libssl/src/crypto/rsa/rsa_lib.c b/src/lib/libssl/src/crypto/rsa/rsa_lib.c
index 93235744f7..f71870a338 100644
--- a/src/lib/libssl/src/crypto/rsa/rsa_lib.c
+++ b/src/lib/libssl/src/crypto/rsa/rsa_lib.c
@@ -181,6 +181,10 @@ RSA *RSA_new_method(ENGINE *engine)
                 OPENSSL_free(ret);
                 ret=NULL;
                 }
+
+        /* Enforce blinding. */
+        ret->flags |= RSA_FLAG_BLINDING;
+
         return(ret);
         }