lib: Make crypt.c independent source file

The cryptography functions were in a C source that was directly
imported into dev.c, enabling ECDHE+AES256 symmetric key encryption on
flows. Now crypt.c is an independent source file with associated
crypt.h header, to prepare for security management and configuration
in the IRMd.

Signed-off-by: Dimitri Staessens <[email protected]>
Signed-off-by: Sander Vrijders <[email protected]>

1 files changed, 56 insertions, 0 deletions

diff --git a/include/ouroboros/crypt.h b/include/ouroboros/crypt.h
new file mode 100644
index 00000000..dd58d798
--- /dev/null
+++ b/include/ouroboros/crypt.h
@@ -0,0 +1,56 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2023
+ *
+ * Cryptography
+ *
+ *    Dimitri Staessens <[email protected]>
+ *    Sander Vrijders   <[email protected]>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * version 2.1 as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., http://www.fsf.org/about/contact/.
+ */
+
+#ifndef OUROBOROS_LIB_CRYPT_H
+#define OUROBOROS_LIB_CRYPT_H
+
+#include <ouroboros/shm_du_buff.h>
+
+#define SYMMKEYSZ 32
+
+struct crypt_info {
+    uint16_t flags;
+    void *   ctx;
+    uint8_t  key[SYMMKEYSZ];
+};
+
+int  crypt_dh_pkp_create(void **   pkp,
+                         uint8_t * pk);
+
+void crypt_dh_pkp_destroy(void * pkp);
+
+int  crypt_dh_derive(void *    pkp,
+                     uint8_t * pk,
+                     size_t    len,
+                     uint8_t * s);
+
+int  crypt_encrypt(struct crypt_info *  info,
+                   struct shm_du_buff * sdb);
+
+int  crypt_decrypt(struct crypt_info *  info,
+                   struct shm_du_buff * sdb);
+
+int  crypt_init(struct crypt_info * info);
+
+void crypt_fini(struct crypt_info * info);
+
+#endif /* OUROBOROS_LIB_CRYPT_H */
\ No newline at end of file