[crypto] Add support for loading an alternative Engine

Add support to plug in alternative implementations for
some or all of the cryptographic operations supported by
the OpenSSL Engine API.
When configured appropriately, OpenSSL calls the engine's
implementation of these operations instead of its own.

1 files changed, 177 insertions, 0 deletions

diff --git a/lib/crypto/c_src/otp_test_engine.c b/lib/crypto/c_src/otp_test_engine.c
new file mode 100644
index 0000000000..414e89c0f6
--- /dev/null
+++ b/lib/crypto/c_src/otp_test_engine.c
@@ -0,0 +1,177 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 2017-2017. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#ifdef _WIN32
+#define OPENSSL_OPT_WINDLL
+#endif
+#include <stdio.h>
+#include <string.h>
+
+#include <openssl/engine.h>
+#include <openssl/md5.h>
+
+#define PACKED_OPENSSL_VERSION(MAJ, MIN, FIX, P)	\
+    ((((((((MAJ << 8) | MIN) << 8 ) | FIX) << 8) | (P-'a'+1)) << 4) | 0xf)
+
+#define PACKED_OPENSSL_VERSION_PLAIN(MAJ, MIN, FIX) \
+    PACKED_OPENSSL_VERSION(MAJ,MIN,FIX,('a'-1))
+
+#if OPENSSL_VERSION_NUMBER < PACKED_OPENSSL_VERSION_PLAIN(1,1,0) \
+    || defined(LIBRESSL_VERSION_NUMBER)
+#define OLD
+#endif
+
+static const char *test_engine_id = "MD5";
+static const char *test_engine_name = "MD5 test engine";
+
+static int test_init(ENGINE *e) {
+    printf("OTP Test Engine Initializatzion!\r\n");
+    return 111;
+}
+
+static void add_test_data(unsigned char *md, unsigned int len)
+{
+    unsigned int i;
+
+    for (i=0; i<len; i++) {
+        md[i] = (unsigned char)(i & 0xff);
+    }
+}
+
+/* MD5 part */
+#undef data
+#ifdef OLD
+#define data(ctx) ((MD5_CTX *)ctx->md_data)
+#endif
+
+static int test_engine_md5_init(EVP_MD_CTX *ctx) {
+    fprintf(stderr, "MD5 initialized\r\n");
+#ifdef OLD
+    return MD5_Init(data(ctx));
+#else
+    return 1;
+#endif
+}
+
+static int test_engine_md5_update(EVP_MD_CTX *ctx,const void *data, size_t count)
+{
+    fprintf(stderr, "MD5 update\r\n");
+#ifdef OLD
+    return MD5_Update(data(ctx), data, (size_t)count);
+#else
+    return 1;
+#endif
+}
+
+static int test_engine_md5_final(EVP_MD_CTX *ctx,unsigned char *md) {
+#ifdef OLD
+    int ret;
+
+    fprintf(stderr, "MD5 final size of EVP_MD: %lu\r\n", sizeof(EVP_MD));
+    ret = MD5_Final(md, data(ctx));
+
+    if (ret > 0) {
+         add_test_data(md, MD5_DIGEST_LENGTH);
+    }
+    return ret;
+#else
+    fprintf(stderr, "MD5 final\r\n");
+    add_test_data(md, MD5_DIGEST_LENGTH);
+    return 1;
+#endif
+}
+
+#ifdef OLD
+static EVP_MD test_engine_md5_method=  {
+        NID_md5,                      /* The name ID for MD5 */
+        NID_undef,                    /* IGNORED: MD5 with private key encryption NID */
+        MD5_DIGEST_LENGTH,            /* Size of MD5 result, in bytes */
+        0,                            /* Flags */
+        test_engine_md5_init,         /* digest init */
+        test_engine_md5_update,       /* digest update */
+        test_engine_md5_final,        /* digest final */
+        NULL,                         /* digest copy */
+        NULL,                         /* digest cleanup */
+        EVP_PKEY_NULL_method,         /* IGNORED: pkey methods */
+        MD5_CBLOCK,                   /* Internal blocksize, see rfc1321/md5.h */
+        sizeof(EVP_MD *) + sizeof(MD5_CTX),
+        NULL,                          /* IGNORED: control function */
+};
+#endif
+
+static int test_digest_ids[] = {NID_md5};
+
+static int test_engine_digest_selector(ENGINE *e, const EVP_MD **digest,
+        const int **nids, int nid) {
+    int ok = 1;
+    if (!digest) {
+        *nids = test_digest_ids;
+        fprintf(stderr, "Digest is empty! Nid:%d\r\n", nid);
+        return 2;
+    }
+    fprintf(stderr, "Digest no %d requested\r\n",nid);
+    if (nid == NID_md5) {
+#ifdef OLD
+        *digest = &test_engine_md5_method;
+#else
+        EVP_MD *md = EVP_MD_meth_new(NID_md5, NID_undef);
+        if (!md ||
+            !EVP_MD_meth_set_result_size(md, MD5_DIGEST_LENGTH) ||
+            !EVP_MD_meth_set_flags(md, 0) ||
+            !EVP_MD_meth_set_init(md,  test_engine_md5_init) ||
+            !EVP_MD_meth_set_update(md,  test_engine_md5_update) ||
+            !EVP_MD_meth_set_final(md,  test_engine_md5_final) ||
+            !EVP_MD_meth_set_copy(md,  NULL) ||
+            !EVP_MD_meth_set_cleanup(md,  NULL) ||
+            !EVP_MD_meth_set_input_blocksize(md, MD5_CBLOCK) ||
+            !EVP_MD_meth_set_app_datasize(md, sizeof(EVP_MD *) + sizeof(MD5_CTX)) ||
+            !EVP_MD_meth_set_ctrl(md, NULL))
+            {
+                ok = 0;
+                *digest = NULL;
+            } else
+            {
+                *digest = md;
+            }
+#endif
+    }
+    else {
+        ok = 0;
+        *digest = NULL;
+    }
+    return ok;
+}
+
+
+static int bind_helper(ENGINE * e, const char *id)
+{
+    if (!ENGINE_set_id(e, test_engine_id) ||
+        !ENGINE_set_name(e, test_engine_name) ||
+        !ENGINE_set_init_function(e, test_init) ||
+        !ENGINE_set_digests(e, &test_engine_digest_selector)
+        )
+        return 0;
+
+    return 1;
+}
+
+IMPLEMENT_DYNAMIC_CHECK_FN();
+
+IMPLEMENT_DYNAMIC_BIND_FN(bind_helper);