lib: Add authentication functions

Adds functions needed for authentication using X509 certificates,
implemented using OpenSSL.

Refactors some library internals, and adds some unit tests for them.

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

1 files changed, 106 insertions, 0 deletions

diff --git a/src/lib/crypt/openssl.h b/src/lib/crypt/openssl.h
new file mode 100644
index 00000000..5d6f50dd
--- /dev/null
+++ b/src/lib/crypt/openssl.h
@@ -0,0 +1,106 @@
+/*
+ * Ouroboros - Copyright (C) 2016 - 2024
+ *
+ * OpenSSL based cryptographic operations
+ * Elliptic curve Diffie-Hellman key exchange
+ * AES encryption
+ # Authentication
+ *
+ *    Dimitri Staessens <dimitri@ouroboros.rocks>
+ *    Sander Vrijders   <sander@ouroboros.rocks>
+ *
+ * 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_OPENSSL_H
+#define OUROBOROS_LIB_CRYPT_OPENSSL_H
+
+ssize_t openssl_ecdh_pkp_create(void **   pkp,
+                                uint8_t * pk);
+
+void    openssl_ecdh_pkp_destroy(void * pkp);
+
+int     openssl_ecdh_derive(void *    pkp,
+                            buffer_t  pk,
+                            uint8_t * s);
+
+int     openssl_encrypt(void *     ctx,
+                        uint8_t *  key,
+                        buffer_t   in,
+                        buffer_t * out);
+
+int     openssl_decrypt(void *     ctx,
+                        uint8_t *  key,
+                        buffer_t   in,
+                        buffer_t * out);
+
+void *  openssl_crypt_create_ctx(void);
+
+void    openssl_crypt_destroy_ctx(void * ctx);
+
+/* AUTHENTICATION */
+
+int     openssl_load_crt_file(const char * path,
+                              void **      crt);
+
+int     openssl_load_crt_str(const char * str,
+                             void **      crt);
+
+int     openssl_get_pubkey_crt(void *  crt,
+                               void ** pk);
+
+void    openssl_free_crt(void * crt);
+
+int     openssl_load_privkey_file(const char * path,
+                                  void **      key);
+
+int     openssl_load_privkey_str(const char * str,
+                                 void **      key);
+
+int     openssl_load_pubkey_file(const char * path,
+                                 void **      key);
+
+int     openssl_load_pubkey_str(const char * str,
+                                void **      key);
+
+int     openssl_cmp_key(const void * key1,
+                        const void * key2);
+
+void    openssl_free_key(void * key);
+
+int     openssl_check_crt_name(void *       crt,
+                               const char * name);
+
+int     openssl_crt_str(void * crt,
+                        char * str);
+
+void *  openssl_auth_create_store(void);
+
+void    openssl_auth_destroy_store(void * store);
+
+int     openssl_auth_add_crt_to_store(void * store,
+                                      void * crt);
+
+int     openssl_verify_crt(void * store,
+                           void * crt);
+
+int     openssl_sign(void *     pkp,
+                     buffer_t   msg,
+                     buffer_t * sig);
+
+int     openssl_verify_sig(void *   pk,
+                           buffer_t msg,
+                           buffer_t sig);
+
+#endif /* OUROBOROS_LIB_CRYPT_OPENSSL_H */