Add |DH_generate_parameters| to decrepit.

This makes building OpenLDAP easier.

Change-Id: Id64699f95477fb8fb98957027c97070ebf41f4b1
Reviewed-on: https://boringssl-review.googlesource.com/7407
Reviewed-by: David Benjamin <davidben@google.com>

3 files changed, 114 insertions, 0 deletions

diff --git a/decrepit/CMakeLists.txt b/decrepit/CMakeLists.txt
index 7ff5c10c..cb6e20d7 100644
--- a/decrepit/CMakeLists.txt
+++ b/decrepit/CMakeLists.txt
@@ -2,6 +2,7 @@ add_subdirectory(bio)
 add_subdirectory(blowfish)
 add_subdirectory(cast)
 add_subdirectory(des)
+add_subdirectory(dh)
 add_subdirectory(dsa)
 add_subdirectory(evp)
 add_subdirectory(obj)
@@ -18,6 +19,7 @@ add_library(
   $<TARGET_OBJECTS:blowfish>
   $<TARGET_OBJECTS:cast>
   $<TARGET_OBJECTS:des_decrepit>
+  $<TARGET_OBJECTS:dh_decrepit>
   $<TARGET_OBJECTS:dsa_decrepit>
   $<TARGET_OBJECTS:evp_decrepit>
   $<TARGET_OBJECTS:obj_decrepit>
diff --git a/decrepit/dh/CMakeLists.txt b/decrepit/dh/CMakeLists.txt
new file mode 100644
index 00000000..fb862b51
--- /dev/null
+++ b/decrepit/dh/CMakeLists.txt
@@ -0,0 +1,9 @@
+include_directories(../../include)
+
+add_library(
+  dh_decrepit
+
+  OBJECT
+
+  dh_decrepit.c
+)
diff --git a/decrepit/dh/dh_decrepit.c b/decrepit/dh/dh_decrepit.c
new file mode 100644
index 00000000..1d38c12e
--- /dev/null
+++ b/decrepit/dh/dh_decrepit.c
@@ -0,0 +1,103 @@
+/* ====================================================================
+ * Copyright (c) 1998-2002 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 <openssl/bn.h>
+#include <openssl/dh.h>
+
+
+struct wrapped_callback {
+  void (*callback)(int, int, void *);
+  void *arg;
+};
+
+/* callback_wrapper converts an “old” style generation callback to the newer
+ * |BN_GENCB| form. */
+static int callback_wrapper(int event, int n, BN_GENCB *gencb) {
+  struct wrapped_callback *wrapped = (struct wrapped_callback *) gencb->arg;
+  wrapped->callback(event, n, wrapped->arg);
+  return 1;
+}
+
+DH *DH_generate_parameters(int prime_len, int generator,
+                           void (*callback)(int, int, void *), void *cb_arg) {
+  if (prime_len < 0 || generator < 0) {
+      return NULL;
+  }
+
+  DH *ret = DH_new();
+  if (ret == NULL) {
+      return NULL;
+  }
+
+  BN_GENCB gencb_storage;
+  BN_GENCB *cb = NULL;
+
+  struct wrapped_callback wrapped;
+
+  if (callback != NULL) {
+    wrapped.callback = callback;
+    wrapped.arg = cb_arg;
+
+    cb = &gencb_storage;
+    BN_GENCB_set(cb, callback_wrapper, &wrapped);
+  }
+
+  if (!DH_generate_parameters_ex(ret, prime_len, generator, cb)) {
+    goto err;
+  }
+
+  return ret;
+
+err:
+  DH_free(ret);
+  return NULL;
+}