Make default_method mostly compile-time

Document thread-safety issues
Have RSA_null return NULL (always fails)

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2244)

11 files changed, 56 insertions, 170 deletions

diff --git a/crypto/dh/dh_key.c b/crypto/dh/dh_key.c
index 204e5a7a42..fce9ff47f3 100644
--- a/crypto/dh/dh_key.c
+++ b/crypto/dh/dh_key.c
@@ -56,11 +56,23 @@ static DH_METHOD dh_ossl = {
     NULL
 };
 
+static const DH_METHOD *default_DH_method = &dh_ossl;
+
 const DH_METHOD *DH_OpenSSL(void)
 {
     return &dh_ossl;
 }
 
+void DH_set_default_method(const DH_METHOD *meth)
+{
+    default_DH_method = meth;
+}
+
+const DH_METHOD *DH_get_default_method(void)
+{
+    return default_DH_method;
+}
+
 static int generate_key(DH *dh)
 {
     int ok = 0;
diff --git a/crypto/dh/dh_lib.c b/crypto/dh/dh_lib.c
index 3dfe7c4e58..f22bcf0706 100644
--- a/crypto/dh/dh_lib.c
+++ b/crypto/dh/dh_lib.c
@@ -13,20 +13,6 @@
 #include "dh_locl.h"
 #include <openssl/engine.h>
 
-static const DH_METHOD *default_DH_method = NULL;
-
-void DH_set_default_method(const DH_METHOD *meth)
-{
-    default_DH_method = meth;
-}
-
-const DH_METHOD *DH_get_default_method(void)
-{
-    if (!default_DH_method)
-        default_DH_method = DH_OpenSSL();
-    return default_DH_method;
-}
-
 int DH_set_method(DH *dh, const DH_METHOD *meth)
 {
     /*
diff --git a/crypto/dsa/dsa_lib.c b/crypto/dsa/dsa_lib.c
index e24c6b526f..c90d09b0f0 100644
--- a/crypto/dsa/dsa_lib.c
+++ b/crypto/dsa/dsa_lib.c
@@ -17,20 +17,6 @@
 #include <openssl/engine.h>
 #include <openssl/dh.h>
 
-static const DSA_METHOD *default_DSA_method = NULL;
-
-void DSA_set_default_method(const DSA_METHOD *meth)
-{
-    default_DSA_method = meth;
-}
-
-const DSA_METHOD *DSA_get_default_method(void)
-{
-    if (!default_DSA_method)
-        default_DSA_method = DSA_OpenSSL();
-    return default_DSA_method;
-}
-
 DSA *DSA_new(void)
 {
     return DSA_new_method(NULL);
diff --git a/crypto/dsa/dsa_ossl.c b/crypto/dsa/dsa_ossl.c
index f9f6a136fb..479337763b 100644
--- a/crypto/dsa/dsa_ossl.c
+++ b/crypto/dsa/dsa_ossl.c
@@ -41,6 +41,18 @@ static DSA_METHOD openssl_dsa_meth = {
     NULL
 };
 
+static const DSA_METHOD *default_DSA_method = &openssl_dsa_meth;
+
+void DSA_set_default_method(const DSA_METHOD *meth)
+{
+    default_DSA_method = meth;
+}
+
+const DSA_METHOD *DSA_get_default_method(void)
+{
+    return default_DSA_method;
+}
+
 const DSA_METHOD *DSA_OpenSSL(void)
 {
     return &openssl_dsa_meth;
diff --git a/crypto/rsa/build.info b/crypto/rsa/build.info
index 39b7464b0e..4575b28879 100644
--- a/crypto/rsa/build.info
+++ b/crypto/rsa/build.info
@@ -1,6 +1,6 @@
 LIBS=../../libcrypto
 SOURCE[../../libcrypto]=\
         rsa_ossl.c rsa_gen.c rsa_lib.c rsa_sign.c rsa_saos.c rsa_err.c \
-        rsa_pk1.c rsa_ssl.c rsa_none.c rsa_oaep.c rsa_chk.c rsa_null.c \
+        rsa_pk1.c rsa_ssl.c rsa_none.c rsa_oaep.c rsa_chk.c \
         rsa_pss.c rsa_x931.c rsa_asn1.c rsa_depr.c rsa_ameth.c rsa_prn.c \
         rsa_pmeth.c rsa_crpt.c rsa_x931g.c rsa_meth.c
diff --git a/crypto/rsa/rsa_err.c b/crypto/rsa/rsa_err.c
index 112e5a46ec..c3698986be 100644
--- a/crypto/rsa/rsa_err.c
+++ b/crypto/rsa/rsa_err.c
@@ -41,11 +41,6 @@ static ERR_STRING_DATA RSA_str_functs[] = {
     {ERR_FUNC(RSA_F_RSA_METH_SET1_NAME), "RSA_meth_set1_name"},
     {ERR_FUNC(RSA_F_RSA_MGF1_TO_MD), "rsa_mgf1_to_md"},
     {ERR_FUNC(RSA_F_RSA_NEW_METHOD), "RSA_new_method"},
-    {ERR_FUNC(RSA_F_RSA_NULL), "RSA_NULL"},
-    {ERR_FUNC(RSA_F_RSA_NULL_PRIVATE_DECRYPT), "RSA_null_private_decrypt"},
-    {ERR_FUNC(RSA_F_RSA_NULL_PRIVATE_ENCRYPT), "RSA_null_private_encrypt"},
-    {ERR_FUNC(RSA_F_RSA_NULL_PUBLIC_DECRYPT), "RSA_null_public_decrypt"},
-    {ERR_FUNC(RSA_F_RSA_NULL_PUBLIC_ENCRYPT), "RSA_null_public_encrypt"},
     {ERR_FUNC(RSA_F_RSA_OSSL_PRIVATE_DECRYPT), "rsa_ossl_private_decrypt"},
     {ERR_FUNC(RSA_F_RSA_OSSL_PRIVATE_ENCRYPT), "rsa_ossl_private_encrypt"},
     {ERR_FUNC(RSA_F_RSA_OSSL_PUBLIC_DECRYPT), "rsa_ossl_public_decrypt"},
diff --git a/crypto/rsa/rsa_lib.c b/crypto/rsa/rsa_lib.c
index 0fbda9a9b1..3c2354bbb4 100644
--- a/crypto/rsa/rsa_lib.c
+++ b/crypto/rsa/rsa_lib.c
@@ -17,31 +17,9 @@
 #include "internal/evp_int.h"
 #include "rsa_locl.h"
 
-static const RSA_METHOD *default_RSA_meth = NULL;
-
 RSA *RSA_new(void)
 {
-    RSA *r = RSA_new_method(NULL);
-
-    return r;
-}
-
-void RSA_set_default_method(const RSA_METHOD *meth)
-{
-    default_RSA_meth = meth;
-}
-
-const RSA_METHOD *RSA_get_default_method(void)
-{
-    if (default_RSA_meth == NULL) {
-#ifdef RSA_NULL
-        default_RSA_meth = RSA_null_method();
-#else
-        default_RSA_meth = RSA_PKCS1_OpenSSL();
-#endif
-    }
-
-    return default_RSA_meth;
+    return RSA_new_method(NULL);
 }
 
 const RSA_METHOD *RSA_get_method(const RSA *rsa)
diff --git a/crypto/rsa/rsa_null.c b/crypto/rsa/rsa_null.c
deleted file mode 100644
index d339494120..0000000000
--- a/crypto/rsa/rsa_null.c
+++ /dev/null
@@ -1,93 +0,0 @@
-/*
- * Copyright 1999-2016 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
- * in the file LICENSE in the source distribution or at
- * https://www.openssl.org/source/license.html
- */
-
-#include <stdio.h>
-#include "internal/cryptlib.h"
-#include <openssl/bn.h>
-#include "rsa_locl.h"
-
-/*
- * This is a dummy RSA implementation that just returns errors when called.
- * It is designed to allow some RSA functions to work while stopping those
- * covered by the RSA patent. That is RSA, encryption, decryption, signing
- * and verify is not allowed but RSA key generation, key checking and other
- * operations (like storing RSA keys) are permitted.
- */
-
-static int RSA_null_public_encrypt(int flen, const unsigned char *from,
-                                   unsigned char *to, RSA *rsa, int padding);
-static int RSA_null_private_encrypt(int flen, const unsigned char *from,
-                                    unsigned char *to, RSA *rsa, int padding);
-static int RSA_null_public_decrypt(int flen, const unsigned char *from,
-                                   unsigned char *to, RSA *rsa, int padding);
-static int RSA_null_private_decrypt(int flen, const unsigned char *from,
-                                    unsigned char *to, RSA *rsa, int padding);
-static int RSA_null_init(RSA *rsa);
-static int RSA_null_finish(RSA *rsa);
-static RSA_METHOD rsa_null_meth = {
-    "Null RSA",
-    RSA_null_public_encrypt,
-    RSA_null_public_decrypt,
-    RSA_null_private_encrypt,
-    RSA_null_private_decrypt,
-    NULL,
-    NULL,
-    RSA_null_init,
-    RSA_null_finish,
-    0,
-    NULL,
-    NULL,
-    NULL,
-    NULL
-};
-
-const RSA_METHOD *RSA_null_method(void)
-{
-    return (&rsa_null_meth);
-}
-
-static int RSA_null_public_encrypt(int flen, const unsigned char *from,
-                                   unsigned char *to, RSA *rsa, int padding)
-{
-    RSAerr(RSA_F_RSA_NULL_PUBLIC_ENCRYPT, RSA_R_RSA_OPERATIONS_NOT_SUPPORTED);
-    return -1;
-}
-
-static int RSA_null_private_encrypt(int flen, const unsigned char *from,
-                                    unsigned char *to, RSA *rsa, int padding)
-{
-    RSAerr(RSA_F_RSA_NULL_PRIVATE_ENCRYPT,
-           RSA_R_RSA_OPERATIONS_NOT_SUPPORTED);
-    return -1;
-}
-
-static int RSA_null_private_decrypt(int flen, const unsigned char *from,
-                                    unsigned char *to, RSA *rsa, int padding)
-{
-    RSAerr(RSA_F_RSA_NULL_PRIVATE_DECRYPT,
-           RSA_R_RSA_OPERATIONS_NOT_SUPPORTED);
-    return -1;
-}
-
-static int RSA_null_public_decrypt(int flen, const unsigned char *from,
-                                   unsigned char *to, RSA *rsa, int padding)
-{
-    RSAerr(RSA_F_RSA_NULL_PUBLIC_DECRYPT, RSA_R_RSA_OPERATIONS_NOT_SUPPORTED);
-    return -1;
-}
-
-static int RSA_null_init(RSA *rsa)
-{
-    return (1);
-}
-
-static int RSA_null_finish(RSA *rsa)
-{
-    return (1);
-}
diff --git a/crypto/rsa/rsa_ossl.c b/crypto/rsa/rsa_ossl.c
index 782606645b..5e0ad92cb1 100644
--- a/crypto/rsa/rsa_ossl.c
+++ b/crypto/rsa/rsa_ossl.c
@@ -11,8 +11,6 @@
 #include "internal/bn_int.h"
 #include "rsa_locl.h"
 
-#ifndef RSA_NULL
-
 static int rsa_ossl_public_encrypt(int flen, const unsigned char *from,
                                   unsigned char *to, RSA *rsa, int padding);
 static int rsa_ossl_private_encrypt(int flen, const unsigned char *from,
@@ -26,7 +24,7 @@ static int rsa_ossl_mod_exp(BIGNUM *r0, const BIGNUM *i, RSA *rsa,
 static int rsa_ossl_init(RSA *rsa);
 static int rsa_ossl_finish(RSA *rsa);
 static RSA_METHOD rsa_pkcs1_ossl_meth = {
-    "OpenSSL PKCS#1 RSA (from Eric Young)",
+    "OpenSSL PKCS#1 RSA",
     rsa_ossl_public_encrypt,
     rsa_ossl_public_decrypt,     /* signature verification */
     rsa_ossl_private_encrypt,    /* signing */
@@ -43,11 +41,28 @@ static RSA_METHOD rsa_pkcs1_ossl_meth = {
     NULL                        /* rsa_keygen */
 };
 
+static const RSA_METHOD *default_RSA_meth = &rsa_pkcs1_ossl_meth;
+
+void RSA_set_default_method(const RSA_METHOD *meth)
+{
+    default_RSA_meth = meth;
+}
+
+const RSA_METHOD *RSA_get_default_method(void)
+{
+    return default_RSA_meth;
+}
+
 const RSA_METHOD *RSA_PKCS1_OpenSSL(void)
 {
     return &rsa_pkcs1_ossl_meth;
 }
 
+const RSA_METHOD *RSA_null_method(void)
+{
+    return NULL;
+}
+
 static int rsa_ossl_public_encrypt(int flen, const unsigned char *from,
                                   unsigned char *to, RSA *rsa, int padding)
 {
@@ -786,5 +801,3 @@ static int rsa_ossl_finish(RSA *rsa)
     BN_MONT_CTX_free(rsa->_method_mod_q);
     return (1);
 }
-
-#endif
diff --git a/crypto/ui/ui_lib.c b/crypto/ui/ui_lib.c
index 7f30a5b0af..e48e4add1d 100644
--- a/crypto/ui/ui_lib.c
+++ b/crypto/ui/ui_lib.c
@@ -15,8 +15,6 @@
 #include <openssl/err.h>
 #include "ui_locl.h"
 
-static const UI_METHOD *default_UI_meth = NULL;
-
 UI *UI_new(void)
 {
     return (UI_new_method(NULL));
@@ -535,19 +533,6 @@ void *UI_get_ex_data(UI *r, int idx)
     return (CRYPTO_get_ex_data(&r->ex_data, idx));
 }
 
-void UI_set_default_method(const UI_METHOD *meth)
-{
-    default_UI_meth = meth;
-}
-
-const UI_METHOD *UI_get_default_method(void)
-{
-    if (default_UI_meth == NULL) {
-        default_UI_meth = UI_OpenSSL();
-    }
-    return default_UI_meth;
-}
-
 const UI_METHOD *UI_get_method(UI *ui)
 {
     return ui->meth;
diff --git a/crypto/ui/ui_openssl.c b/crypto/ui/ui_openssl.c
index 400b0562f4..42c932656c 100644
--- a/crypto/ui/ui_openssl.c
+++ b/crypto/ui/ui_openssl.c
@@ -202,6 +202,18 @@ static UI_METHOD ui_openssl = {
     NULL
 };
 
+static const UI_METHOD *default_UI_meth = &ui_openssl;
+
+void UI_set_default_method(const UI_METHOD *meth)
+{
+    default_UI_meth = meth;
+}
+
+const UI_METHOD *UI_get_default_method(void)
+{
+    return default_UI_meth;
+}
+
 /* The method with all the built-in thingies */
 UI_METHOD *UI_OpenSSL(void)
 {