free NULL cleanup

Start ensuring all OpenSSL "free" routines allow NULL, and remove
any if check before calling them.
This gets DH_free, DSA_free, RSA_free
Reviewed-by: NMatt Caswell <matt@openssl.org>

apps/dh.c

@@ -314,8 +314,7 @@ int MAIN(int argc, char **argv)
         BIO_free(in);
     if (out != NULL)
         BIO_free_all(out);
-    if (dh != NULL)
-        DH_free(dh);
+    DH_free(dh);
     apps_shutdown();
     OPENSSL_EXIT(ret);
 }

apps/dhparam.c

@@ -319,8 +319,7 @@ int MAIN(int argc, char **argv)
             if (!dsa
                 || !DSA_generate_parameters_ex(dsa, num, NULL, 0, NULL, NULL,
                                                cb)) {
-                if (dsa)
-                    DSA_free(dsa);
+                DSA_free(dsa);
                 BN_GENCB_free(cb);
                 ERR_print_errors(bio_err);
                 goto end;
@@ -520,8 +519,7 @@ int MAIN(int argc, char **argv)
         BIO_free(in);
     if (out != NULL)
         BIO_free_all(out);
-    if (dh != NULL)
-        DH_free(dh);
+    DH_free(dh);
     apps_shutdown();
     OPENSSL_EXIT(ret);
 }

apps/dsa.c

@@ -360,8 +360,7 @@ int MAIN(int argc, char **argv)
         BIO_free(in);
     if (out != NULL)
         BIO_free_all(out);
-    if (dsa != NULL)
-        DSA_free(dsa);
+    DSA_free(dsa);
     if (passin)
         OPENSSL_free(passin);
     if (passout)

apps/dsaparam.c

@@ -438,8 +438,7 @@ int MAIN(int argc, char **argv)
         BIO_free(in);
     if (out != NULL)
         BIO_free_all(out);
-    if (dsa != NULL)
-        DSA_free(dsa);
+    DSA_free(dsa);
     apps_shutdown();
     OPENSSL_EXIT(ret);
 }

apps/gendh.c

@@ -212,8 +212,7 @@ int MAIN(int argc, char **argv)
         ERR_print_errors(bio_err);
     if (out != NULL)
         BIO_free_all(out);
-    if (dh != NULL)
-        DH_free(dh);
+    DH_free(dh);
     if (cb != NULL)
         BN_GENCB_free(cb);
     apps_shutdown();

apps/gendsa.c

@@ -271,8 +271,7 @@ int MAIN(int argc, char **argv)
         BIO_free(in);
     if (out != NULL)
         BIO_free_all(out);
-    if (dsa != NULL)
-        DSA_free(dsa);
+    DSA_free(dsa);
     if (passout)
         OPENSSL_free(passout);
     apps_shutdown();

apps/genrsa.c

@@ -311,8 +311,7 @@ int MAIN(int argc, char **argv)
         BN_free(bn);
     if (cb)
         BN_GENCB_free(cb);
-    if (rsa)
-        RSA_free(rsa);
+    RSA_free(rsa);
     if (out)
         BIO_free_all(out);
     if (passout)

apps/rsa.c

@@ -424,8 +424,7 @@ int MAIN(int argc, char **argv)
  end:
     if (out != NULL)
         BIO_free_all(out);
-    if (rsa != NULL)
-        RSA_free(rsa);
+    RSA_free(rsa);
     if (passin)
         OPENSSL_free(passin);
     if (passout)

apps/s_server.c

@@ -3180,8 +3180,7 @@ static RSA *tmp_rsa_cb(SSL *s, int is_export, int keylength)
         }
         if (!BN_set_word(bn, RSA_F4) || ((rsa_tmp = RSA_new()) == NULL) ||
             !RSA_generate_key_ex(rsa_tmp, keylength, bn, NULL)) {
-            if (rsa_tmp)
-                RSA_free(rsa_tmp);
+            RSA_free(rsa_tmp);
             rsa_tmp = NULL;
         }
         if (!s_quiet) {

apps/speed.c

@@ -2448,13 +2448,11 @@ int MAIN(int argc, char **argv)
         OPENSSL_free(buf2_malloc);
 #ifndef OPENSSL_NO_RSA
     for (i = 0; i < RSA_NUM; i++)
-        if (rsa_key[i] != NULL)
-            RSA_free(rsa_key[i]);
+        RSA_free(rsa_key[i]);
 #endif
 #ifndef OPENSSL_NO_DSA
     for (i = 0; i < DSA_NUM; i++)
-        if (dsa_key[i] != NULL)
-            DSA_free(dsa_key[i]);
+        DSA_free(dsa_key[i]);
 #endif
 
 #ifndef OPENSSL_NO_EC

crypto/dh/dh_ameth.c

@@ -142,8 +142,7 @@ static int dh_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
  err:
     if (public_key)
         ASN1_INTEGER_free(public_key);
-    if (dh)
-        DH_free(dh);
+    DH_free(dh);
     return 0;
 
 }
@@ -711,8 +710,7 @@ static int dh_cms_set_peerkey(EVP_PKEY_CTX *pctx,
         ASN1_INTEGER_free(public_key);
     if (pkpeer)
         EVP_PKEY_free(pkpeer);
-    if (dhpeer)
-        DH_free(dhpeer);
+    DH_free(dhpeer);
     return rv;
 }
 

crypto/dh/dh_asn1.c

@@ -142,8 +142,7 @@ DH *d2i_DHxparams(DH **a, const unsigned char **pp, long length)
     }
 
     if (a) {
-        if (*a)
-            DH_free(*a);
+        DH_free(*a);
         *a = dh;
     }
 

crypto/dh/dh_lib.c

@@ -170,6 +170,7 @@ DH *DH_new_method(ENGINE *engine)
 void DH_free(DH *r)
 {
     int i;
+
     if (r == NULL)
         return;
     i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH);

crypto/dh/dhtest.c

@@ -199,10 +199,8 @@ int main(int argc, char *argv[])
         OPENSSL_free(abuf);
     if (bbuf != NULL)
         OPENSSL_free(bbuf);
-    if (b != NULL)
-        DH_free(b);
-    if (a != NULL)
-        DH_free(a);
+    DH_free(b);
+    DH_free(a);
     if (_cb)
         BN_GENCB_free(_cb);
     BIO_free(out);

crypto/dsa/dsa_ameth.c

@@ -120,8 +120,7 @@ static int dsa_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey)
  err:
     if (public_key)
         ASN1_INTEGER_free(public_key);
-    if (dsa)
-        DSA_free(dsa);
+    DSA_free(dsa);
     return 0;
 
 }

crypto/dsa/dsa_depr.c

@@ -89,10 +89,8 @@ DSA *DSA_generate_parameters(int bits,
     if ((ret = DSA_new()) == NULL)
         return NULL;
     cb = BN_GENCB_new();
-    if (!cb) {
-        DSA_free(ret);
-        return NULL;
-    }
+    if (!cb)
+        goto err;
 
     BN_GENCB_set_old(cb, callback, cb_arg);
 
@@ -102,6 +100,7 @@ DSA *DSA_generate_parameters(int bits,
         return ret;
     }
     BN_GENCB_free(cb);
+err:
     DSA_free(ret);
     return NULL;
 }

crypto/dsa/dsa_lib.c

@@ -315,8 +315,7 @@ DH *DSA_dup_DH(const DSA *r)
     return ret;
 
  err:
-    if (ret != NULL)
-        DH_free(ret);
+    DH_free(ret);
     return NULL;
 }
 #endif

crypto/dsa/dsatest.c

@@ -211,8 +211,7 @@ int main(int argc, char **argv)
  end:
     if (!ret)
         ERR_print_errors(bio_err);
-    if (dsa != NULL)
-        DSA_free(dsa);
+    DSA_free(dsa);
     if (cb != NULL)
         BN_GENCB_free(cb);
     CRYPTO_cleanup_all_ex_data();

crypto/evp/evp_extra_test.c

@@ -268,9 +268,7 @@ static EVP_PKEY *load_example_rsa_key(void)
     if (pkey) {
         EVP_PKEY_free(pkey);
     }
-    if (rsa) {
-        RSA_free(rsa);
-    }
+    RSA_free(rsa);
 
     return ret;
 }

crypto/pem/pvkfmt.c

@@ -335,8 +335,7 @@ static EVP_PKEY *b2i_dss(const unsigned char **in, unsigned int length,
 
  memerr:
     PEMerr(PEM_F_B2I_DSS, ERR_R_MALLOC_FAILURE);
-    if (dsa)
-        DSA_free(dsa);
+    DSA_free(dsa);
     if (ret)
         EVP_PKEY_free(ret);
     if (ctx)
@@ -385,8 +384,7 @@ static EVP_PKEY *b2i_rsa(const unsigned char **in, unsigned int length,
     return ret;
  memerr:
     PEMerr(PEM_F_B2I_RSA, ERR_R_MALLOC_FAILURE);
-    if (rsa)
-        RSA_free(rsa);
+    RSA_free(rsa);
     if (ret)
         EVP_PKEY_free(ret);
     return NULL;

crypto/rsa/rsa_depr.c

@@ -101,8 +101,7 @@ RSA *RSA_generate_key(int bits, unsigned long e_value,
  err:
     if (e)
         BN_free(e);
-    if (rsa)
-        RSA_free(rsa);
+    RSA_free(rsa);
     if (cb)
         BN_GENCB_free(cb);
     return 0;

demos/easy_tls/easy-tls.c

@@ -637,8 +637,7 @@ void tls_set_dhe1024(int i, void *apparg)
         tls_openssl_errors("", "", NULL, apparg);
         return;
     }
-    if (tls_dhe1024 != NULL)
-        DH_free(tls_dhe1024);
+    DH_free(tls_dhe1024);
     tls_dhe1024 = dhparams;
 }
 

doc/crypto/DH_new.pod

@@ -18,6 +18,7 @@ DH_new() allocates and initializes a B<DH> structure.
 
 DH_free() frees the B<DH> structure and its components. The values are
 erased before the memory is returned to the system.
+If B<dh> is NULL nothing is done.
 
 =head1 RETURN VALUES
 

doc/crypto/DSA_new.pod

@@ -19,6 +19,7 @@ calling DSA_new_method(NULL).
 
 DSA_free() frees the B<DSA> structure and its components. The values are
 erased before the memory is returned to the system.
+If B<dsa> is NULL nothing is done.
 
 =head1 RETURN VALUES
 

doc/crypto/RSA_new.pod

@@ -19,6 +19,7 @@ calling RSA_new_method(NULL).
 
 RSA_free() frees the B<RSA> structure and its components. The key is
 erased before the memory is returned to the system.
+If B<rsa> is NULL nothing is done.
 
 =head1 RETURN VALUES
 

engines/ccgost/gost_ameth.c

@@ -276,9 +276,7 @@ static int pkey_ctrl_gost(EVP_PKEY *pkey, int op, long arg1, void *arg2)
 /* --------------------- free functions * ------------------------------*/
 static void pkey_free_gost94(EVP_PKEY *key)
 {
-    if (key->pkey.dsa) {
-        DSA_free(key->pkey.dsa);
-    }
+    DSA_free(key->pkey.dsa);
 }
 
 static void pkey_free_gost01(EVP_PKEY *key)

engines/e_capi.c

@@ -754,10 +754,8 @@ static EVP_PKEY *capi_get_pkey(ENGINE *eng, CAPI_KEY * key)
     if (pubkey)
         OPENSSL_free(pubkey);
     if (!ret) {
-        if (rkey)
-            RSA_free(rkey);
-        if (dkey)
-            DSA_free(dkey);
+        RSA_free(rkey);
+        DSA_free(dkey);
     }
 
     return ret;

engines/e_chil.c

@@ -849,8 +849,7 @@ static EVP_PKEY *hwcrhk_load_privkey(ENGINE *eng, const char *key_id,
     return res;
  err:
 #  ifndef OPENSSL_NO_RSA
-    if (rtmp)
-        RSA_free(rtmp);
+    RSA_free(rtmp);
 #  endif
     return NULL;
 }

engines/e_sureware.c

@@ -801,12 +801,10 @@ static EVP_PKEY *sureware_load_public(ENGINE *e, const char *key_id,
     return res;
  err:
 #  ifndef OPENSSL_NO_RSA
-    if (rsatmp)
-        RSA_free(rsatmp);
+    RSA_free(rsatmp);
 #  endif
 #  ifndef OPENSSL_NO_DSA
-    if (dsatmp)
-        DSA_free(dsatmp);
+    DSA_free(dsatmp);
 #  endif
     return NULL;
 }

ssl/s3_clnt.c

@@ -1380,16 +1380,12 @@ int ssl3_get_key_exchange(SSL *s)
     param = p = (unsigned char *)s->init_msg;
     if (s->session->sess_cert != NULL) {
 #ifndef OPENSSL_NO_RSA
-        if (s->session->sess_cert->peer_rsa_tmp != NULL) {
-            RSA_free(s->session->sess_cert->peer_rsa_tmp);
-            s->session->sess_cert->peer_rsa_tmp = NULL;
-        }
+        RSA_free(s->session->sess_cert->peer_rsa_tmp);
+        s->session->sess_cert->peer_rsa_tmp = NULL;
 #endif
 #ifndef OPENSSL_NO_DH
-        if (s->session->sess_cert->peer_dh_tmp) {
-            DH_free(s->session->sess_cert->peer_dh_tmp);
-            s->session->sess_cert->peer_dh_tmp = NULL;
-        }
+        DH_free(s->session->sess_cert->peer_dh_tmp);
+        s->session->sess_cert->peer_dh_tmp = NULL;
 #endif
 #ifndef OPENSSL_NO_EC
         if (s->session->sess_cert->peer_ecdh_tmp) {
@@ -1955,12 +1951,10 @@ int ssl3_get_key_exchange(SSL *s)
  err:
     EVP_PKEY_free(pkey);
 #ifndef OPENSSL_NO_RSA
-    if (rsa != NULL)
-        RSA_free(rsa);
+    RSA_free(rsa);
 #endif
 #ifndef OPENSSL_NO_DH
-    if (dh != NULL)
-        DH_free(dh);
+    DH_free(dh);
 #endif
 #ifndef OPENSSL_NO_EC
     BN_CTX_free(bn_ctx);

ssl/s3_lib.c

@@ -3138,8 +3138,7 @@ void ssl3_free(SSL *s)
     if (s->s3->rrec.comp != NULL)
         OPENSSL_free(s->s3->rrec.comp);
 #ifndef OPENSSL_NO_DH
-    if (s->s3->tmp.dh != NULL)
-        DH_free(s->s3->tmp.dh);
+    DH_free(s->s3->tmp.dh);
 #endif
 #ifndef OPENSSL_NO_EC
     if (s->s3->tmp.ecdh != NULL)
@@ -3181,10 +3180,8 @@ void ssl3_clear(SSL *s)
         s->s3->rrec.comp = NULL;
     }
 #ifndef OPENSSL_NO_DH
-    if (s->s3->tmp.dh != NULL) {
-        DH_free(s->s3->tmp.dh);
-        s->s3->tmp.dh = NULL;
-    }
+    DH_free(s->s3->tmp.dh);
+    s->s3->tmp.dh = NULL;
 #endif
 #ifndef OPENSSL_NO_EC
     if (s->s3->tmp.ecdh != NULL) {
@@ -3293,8 +3290,7 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
                 SSLerr(SSL_F_SSL3_CTRL, ERR_R_RSA_LIB);
                 return (ret);
             }
-            if (s->cert->rsa_tmp != NULL)
-                RSA_free(s->cert->rsa_tmp);
+            RSA_free(s->cert->rsa_tmp);
             s->cert->rsa_tmp = rsa;
             ret = 1;
         }
@@ -3329,8 +3325,7 @@ long ssl3_ctrl(SSL *s, int cmd, long larg, void *parg)
                     return (ret);
                 }
             }
-            if (s->cert->dh_tmp != NULL)
-                DH_free(s->cert->dh_tmp);
+            DH_free(s->cert->dh_tmp);
             s->cert->dh_tmp = dh;
             ret = 1;
         }
@@ -3766,8 +3761,7 @@ long ssl3_ctx_ctrl(SSL_CTX *ctx, int cmd, long larg, void *parg)
                 SSLerr(SSL_F_SSL3_CTX_CTRL, ERR_R_RSA_LIB);
                 return (0);
             } else {
-                if (cert->rsa_tmp != NULL)
-                    RSA_free(cert->rsa_tmp);
+                RSA_free(cert->rsa_tmp);
                 cert->rsa_tmp = rsa;
                 return (1);
             }
@@ -3801,8 +3795,7 @@ long ssl3_ctx_ctrl(SSL_CTX *ctx, int cmd, long larg, void *parg)
                     return 0;
                 }
             }
-            if (cert->dh_tmp != NULL)
-                DH_free(cert->dh_tmp);
+            DH_free(cert->dh_tmp);
             cert->dh_tmp = new;
             return 1;
         }

ssl/ssl_cert.c

@@ -443,12 +443,10 @@ void ssl_cert_free(CERT *c)
 #endif
 
 #ifndef OPENSSL_NO_RSA
-    if (c->rsa_tmp)
-        RSA_free(c->rsa_tmp);
+    RSA_free(c->rsa_tmp);
 #endif
 #ifndef OPENSSL_NO_DH
-    if (c->dh_tmp)
-        DH_free(c->dh_tmp);
+    DH_free(c->dh_tmp);
 #endif
 #ifndef OPENSSL_NO_EC
     if (c->ecdh_tmp)
@@ -651,12 +649,10 @@ void ssl_sess_cert_free(SESS_CERT *sc)
     }
 
 #ifndef OPENSSL_NO_RSA
-    if (sc->peer_rsa_tmp != NULL)
-        RSA_free(sc->peer_rsa_tmp);
+    RSA_free(sc->peer_rsa_tmp);
 #endif
 #ifndef OPENSSL_NO_DH
-    if (sc->peer_dh_tmp != NULL)
-        DH_free(sc->peer_dh_tmp);
+    DH_free(sc->peer_dh_tmp);
 #endif
 #ifndef OPENSSL_NO_EC
     if (sc->peer_ecdh_tmp != NULL)

ssl/ssl_conf.c

@@ -421,8 +421,7 @@ static int cmd_DHParameters(SSL_CONF_CTX *cctx, const char *value)
     if (cctx->ssl)
         rv = SSL_set_tmp_dh(cctx->ssl, dh);
  end:
-    if (dh)
-        DH_free(dh);
+    DH_free(dh);
     if (in)
         BIO_free(in);
     return rv > 0;

ssl/ssltest.c

@@ -2968,10 +2968,8 @@ static RSA *tmp_rsa_cb(SSL *s, int is_export, int keylength)
 
 static void free_tmp_rsa(void)
 {
-    if (rsa_tmp != NULL) {
-        RSA_free(rsa_tmp);
-        rsa_tmp = NULL;
-    }
+    RSA_free(rsa_tmp);
+    rsa_tmp = NULL;
 }
 #endif