Make COMP_CTX and COMP_METHOD opaque

Since COMP_METHOD is now defined in comp_lcl.h, it is no
longer possible to create new TLS compression methods without
using the OpenSSL source.  Only ZLIB is supported by default.
Also, since the types are opaque, #ifdef guards to use "char *"
instead of the real type aren't necessary.

The changes are actually minor.  Adding missing copyright to some
files makes the diff misleadingly big.

Reviewed-by: Matt Caswell <matt@openssl.org>

4 files changed, 207 insertions, 9 deletions

diff --git a/crypto/comp/Makefile b/crypto/comp/Makefile
index 1a180f49df..7884f99547 100644
--- a/crypto/comp/Makefile
+++ b/crypto/comp/Makefile
@@ -68,7 +68,7 @@ c_zlib.o: ../../include/openssl/lhash.h ../../include/openssl/obj_mac.h
 c_zlib.o: ../../include/openssl/objects.h ../../include/openssl/opensslconf.h
 c_zlib.o: ../../include/openssl/opensslv.h ../../include/openssl/ossl_typ.h
 c_zlib.o: ../../include/openssl/safestack.h ../../include/openssl/stack.h
-c_zlib.o: ../../include/openssl/symhacks.h c_zlib.c
+c_zlib.o: ../../include/openssl/symhacks.h c_zlib.c comp_lcl.h
 comp_err.o: ../../include/openssl/bio.h ../../include/openssl/comp.h
 comp_err.o: ../../include/openssl/crypto.h ../../include/openssl/e_os2.h
 comp_err.o: ../../include/openssl/err.h ../../include/openssl/lhash.h
@@ -82,4 +82,4 @@ comp_lib.o: ../../include/openssl/e_os2.h ../../include/openssl/obj_mac.h
 comp_lib.o: ../../include/openssl/objects.h ../../include/openssl/opensslconf.h
 comp_lib.o: ../../include/openssl/opensslv.h ../../include/openssl/ossl_typ.h
 comp_lib.o: ../../include/openssl/safestack.h ../../include/openssl/stack.h
-comp_lib.o: ../../include/openssl/symhacks.h comp_lib.c
+comp_lib.o: ../../include/openssl/symhacks.h comp_lcl.h comp_lib.c
diff --git a/crypto/comp/c_zlib.c b/crypto/comp/c_zlib.c
index 2d5b54f42e..83773a1106 100644
--- a/crypto/comp/c_zlib.c
+++ b/crypto/comp/c_zlib.c
@@ -1,9 +1,64 @@
+/* ====================================================================
+ * Copyright (c) 1999-2015 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
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    openssl-core@OpenSSL.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com).  This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <openssl/objects.h>
 #include <openssl/comp.h>
 #include <openssl/err.h>
+#include "comp_lcl.h"
 
 COMP_METHOD *COMP_zlib(void);
 
@@ -14,8 +69,6 @@ static COMP_METHOD zlib_method_nozlib = {
     NULL,
     NULL,
     NULL,
-    NULL,
-    NULL,
 };
 
 #ifndef ZLIB
diff --git a/crypto/comp/comp_lcl.h b/crypto/comp/comp_lcl.h
new file mode 100644
index 0000000000..f1ec8d5481
--- /dev/null
+++ b/crypto/comp/comp_lcl.h
@@ -0,0 +1,74 @@
+/* ====================================================================
+ * Copyright (c) 2017 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
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    openssl-core@OpenSSL.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com).  This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ */
+
+
+struct comp_method_st {
+    int type;                   /* NID for compression library */
+    const char *name;           /* A text string to identify the library */
+    int (*init) (COMP_CTX *ctx);
+    void (*finish) (COMP_CTX *ctx);
+    int (*compress) (COMP_CTX *ctx,
+                     unsigned char *out, unsigned int olen,
+                     unsigned char *in, unsigned int ilen);
+    int (*expand) (COMP_CTX *ctx,
+                   unsigned char *out, unsigned int olen,
+                   unsigned char *in, unsigned int ilen);
+};
+
+struct comp_ctx_st {
+    struct comp_method_st *meth;
+    unsigned long compress_in;
+    unsigned long compress_out;
+    unsigned long expand_in;
+    unsigned long expand_out;
+};
diff --git a/crypto/comp/comp_lib.c b/crypto/comp/comp_lib.c
index 42d99364a9..aa82376cdd 100644
--- a/crypto/comp/comp_lib.c
+++ b/crypto/comp/comp_lib.c
@@ -1,17 +1,70 @@
+/* ====================================================================
+ * Copyright (c) 1999-2015 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
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. All advertising materials mentioning features or use of this
+ *    software must display the following acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
+ *
+ * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
+ *    endorse or promote products derived from this software without
+ *    prior written permission. For written permission, please contact
+ *    openssl-core@OpenSSL.org.
+ *
+ * 5. Products derived from this software may not be called "OpenSSL"
+ *    nor may "OpenSSL" appear in their names without prior written
+ *    permission of the OpenSSL Project.
+ *
+ * 6. Redistributions of any form whatsoever must retain the following
+ *    acknowledgment:
+ *    "This product includes software developed by the OpenSSL Project
+ *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
+ * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
+ * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ * ====================================================================
+ *
+ * This product includes cryptographic software written by Eric Young
+ * (eay@cryptsoft.com).  This product includes software written by Tim
+ * Hudson (tjh@cryptsoft.com).
+ *
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <openssl/objects.h>
 #include <openssl/comp.h>
+#include "comp_lcl.h"
 
 COMP_CTX *COMP_CTX_new(COMP_METHOD *meth)
 {
     COMP_CTX *ret;
 
-    if ((ret = OPENSSL_malloc(sizeof(*ret))) == NULL) {
-        /* ZZZZZZZZZZZZZZZZ */
+    if ((ret = OPENSSL_malloc(sizeof(*ret))) == NULL)
         return (NULL);
-    }
     memset(ret, 0, sizeof(*ret));
     ret->meth = meth;
     if ((ret->meth->init != NULL) && !ret->meth->init(ret)) {
@@ -21,6 +74,21 @@ COMP_CTX *COMP_CTX_new(COMP_METHOD *meth)
     return (ret);
 }
 
+const COMP_METHOD *COMP_CTX_get_method(const COMP_CTX *ctx)
+{
+    return ctx->meth;
+}
+
+int COMP_get_type(const COMP_METHOD *meth)
+{
+    return meth->type;
+}
+
+const char *COMP_get_name(const COMP_METHOD *meth)
+{
+    return meth->name;
+}
+
 void COMP_CTX_free(COMP_CTX *ctx)
 {
     if (ctx == NULL)
@@ -37,7 +105,6 @@ int COMP_compress_block(COMP_CTX *ctx, unsigned char *out, int olen,
 {
     int ret;
     if (ctx->meth->compress == NULL) {
-        /* ZZZZZZZZZZZZZZZZZ */
         return (-1);
     }
     ret = ctx->meth->compress(ctx, out, olen, in, ilen);
@@ -54,7 +121,6 @@ int COMP_expand_block(COMP_CTX *ctx, unsigned char *out, int olen,
     int ret;
 
     if (ctx->meth->expand == NULL) {
-        /* ZZZZZZZZZZZZZZZZZ */
         return (-1);
     }
     ret = ctx->meth->expand(ctx, out, olen, in, ilen);
@@ -64,3 +130,8 @@ int COMP_expand_block(COMP_CTX *ctx, unsigned char *out, int olen,
     }
     return (ret);
 }
+
+int COMP_CTX_get_type(const COMP_CTX* comp)
+{
+    return comp->meth ? comp->meth->type : NID_undef;
+}