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src-tauri/src/api_crypto.rs

@@ -0,0 +1,92 @@
+//! AES-256-GCM，与 pythonbackend `app/core/aes_crypto.py` 一致。
+
+use rand::RngCore;
+
+use aes_gcm::{
+    aead::{Aead, KeyInit},
+    Aes256Gcm, Nonce,
+};
+use base64::Engine;
+use serde_json::Value;
+
+pub const ENCRYPTED_HEADER: &str = "X-AICLIENT-Encrypted";
+const ENVELOPE_VERSION: i64 = 1;
+
+pub fn parse_aes_key(raw: &str) -> Option<[u8; 32]> {
+    let s = raw.trim();
+    if s.is_empty() {
+        return None;
+    }
+    let bytes = if s.len() == 64 && s.chars().all(|c| c.is_ascii_hexdigit()) {
+        hex::decode(s).ok()?
+    } else {
+        base64::engine::general_purpose::STANDARD
+            .decode(s)
+            .ok()?
+    };
+    if bytes.len() != 32 {
+        return None;
+    }
+    let mut key = [0u8; 32];
+    key.copy_from_slice(&bytes);
+    Some(key)
+}
+
+pub fn aes_key_from_env() -> Option<[u8; 32]> {
+    let s="98cde5e64ee0da6ed0c5842f43a950aa0d8ae5087c43c8d8ee5d10bd8d571bb4";
+    parse_aes_key(&s)
+}
+
+pub fn encrypt_bytes(plaintext: &[u8], key: &[u8; 32]) -> Result<String, String> {
+    let cipher = Aes256Gcm::new_from_slice(key).map_err(|e| e.to_string())?;
+    let mut nonce_bytes = [0u8; 12];
+    rand::RngCore::fill_bytes(&mut rand::thread_rng(), &mut nonce_bytes);
+    let nonce = Nonce::from_slice(&nonce_bytes);
+    let ciphertext = cipher
+        .encrypt(nonce, plaintext)
+        .map_err(|e| format!("加密失败: {e}"))?;
+    let mut combined = nonce_bytes.to_vec();
+    combined.extend(ciphertext);
+    Ok(base64::engine::general_purpose::STANDARD.encode(&combined))
+}
+
+pub fn decrypt_payload(b64_payload: &str, key: &[u8; 32]) -> Result<Vec<u8>, String> {
+    let raw = base64::engine::general_purpose::STANDARD
+        .decode(b64_payload.trim())
+        .map_err(|e| format!("Base64 解码失败: {e}"))?;
+    if raw.len() < 13 {
+        return Err("密文过短".into());
+    }
+    let (nonce_bytes, ciphertext) = raw.split_at(12);
+    let cipher = Aes256Gcm::new_from_slice(key).map_err(|e| e.to_string())?;
+    let nonce = Nonce::from_slice(nonce_bytes);
+    cipher
+        .decrypt(nonce, ciphertext)
+        .map_err(|e| format!("解密失败: {e}"))
+}
+
+pub fn wrap_encrypted(plaintext: &[u8], key: &[u8; 32]) -> Result<String, String> {
+    let payload = encrypt_bytes(plaintext, key)?;
+    let envelope = serde_json::json!({
+        "v": ENVELOPE_VERSION,
+        "payload": payload,
+    });
+    serde_json::to_string(&envelope).map_err(|e| e.to_string())
+}
+
+pub fn unwrap_encrypted(body: &str, key: &[u8; 32]) -> Result<Vec<u8>, String> {
+    let v: Value = serde_json::from_str(body).map_err(|e| format!("信封 JSON 无效: {e}"))?;
+    let version = v.get("v").and_then(|x| x.as_i64());
+    let payload = v
+        .get("payload")
+        .and_then(|x| x.as_str())
+        .ok_or_else(|| "缺少 payload".to_string())?;
+    if version != Some(ENVELOPE_VERSION) {
+        return Err("不支持的加密版本".into());
+    }
+    decrypt_payload(payload, key)
+}
+
+pub fn crypto_enabled() -> bool {
+    aes_key_from_env().is_some()
+}