Completed refactoring to separate nip files, and updating build.sh

nostr_core/nip004.h

@@ -0,0 +1,56 @@
+/*
+ * NIP-04: Encrypted Direct Message
+ * https://github.com/nostr-protocol/nips/blob/master/04.md
+ */
+
+#ifndef NOSTR_NIP004_H
+#define NOSTR_NIP004_H
+
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// NIP-04 constants
+// #define NOSTR_NIP04_MAX_PLAINTEXT_SIZE 65535
+// NIP-04 Constants
+// #define NOSTR_NIP04_MAX_PLAINTEXT_SIZE 16777216    // 16MB
+// #define NOSTR_NIP04_MAX_ENCRYPTED_SIZE 22369621    // ~21.3MB (accounts for base64 overhead + IV)
+/**
+ * NIP-04: Encrypt a message using ECDH + AES-256-CBC
+ * 
+ * @param sender_private_key 32-byte sender private key
+ * @param recipient_public_key 32-byte recipient public key (x-only)
+ * @param plaintext Message to encrypt
+ * @param output Buffer for encrypted output (format: "ciphertext?iv=iv_base64")
+ * @param output_size Size of output buffer
+ * @return NOSTR_SUCCESS on success, error code on failure
+ */
+int nostr_nip04_encrypt(const unsigned char* sender_private_key,
+                       const unsigned char* recipient_public_key, 
+                       const char* plaintext,
+                       char* output,
+                       size_t output_size);
+
+/**
+ * NIP-04: Decrypt a message using ECDH + AES-256-CBC
+ * 
+ * @param recipient_private_key 32-byte recipient private key
+ * @param sender_public_key 32-byte sender public key (x-only)
+ * @param encrypted_data Encrypted message (format: "ciphertext?iv=iv_base64")
+ * @param output Buffer for decrypted plaintext
+ * @param output_size Size of output buffer
+ * @return NOSTR_SUCCESS on success, error code on failure
+ */
+int nostr_nip04_decrypt(const unsigned char* recipient_private_key,
+                       const unsigned char* sender_public_key,
+                       const char* encrypted_data,
+                       char* output,
+                       size_t output_size);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // NOSTR_NIP004_H