feat: implement custom encryption handling in EncryptedHandler

Author: genu

packages/runtime/src/enhancements/edge/encrypted.ts

@@ -1,8 +1,15 @@
 /* eslint-disable @typescript-eslint/no-explicit-any */
 /* eslint-disable @typescript-eslint/no-unused-vars */
 
-import { NestedWriteVisitor, enumerate, getModelFields, resolveField, type PrismaWriteActionType } from '../../cross';
-import { DbClientContract } from '../../types';
+import {
+    FieldInfo,
+    NestedWriteVisitor,
+    enumerate,
+    getModelFields,
+    resolveField,
+    type PrismaWriteActionType,
+} from '../../cross';
+import { DbClientContract, CustomEncryption, SimpleEncryption } from '../../types';
 import { InternalEnhancementOptions } from './create-enhancement';
 import { DefaultPrismaProxyHandler, PrismaProxyActions, makeProxy } from './proxy';
 import { QueryUtils } from './query-utils';
@@ -33,52 +40,65 @@ const getKey = async (secret: string): Promise<CryptoKey> => {
         'decrypt',
     ]);
 };
-const encryptFunc = async (data: string, secret: string): Promise<string> => {
-    const key = await getKey(secret);
-    const iv = crypto.getRandomValues(new Uint8Array(12));
-
-    const encrypted = await crypto.subtle.encrypt(
-        {
-            name: 'AES-GCM',
-            iv,
-        },
-        key,
-        encoder.encode(data)
-    );
 
-    // Combine IV and encrypted data into a single array of bytes
-    const bytes = [...iv, ...new Uint8Array(encrypted)];
+class EncryptedHandler extends DefaultPrismaProxyHandler {
+    private queryUtils: QueryUtils;
 
-    // Convert bytes to base64 string
-    return btoa(String.fromCharCode(...bytes));
-};
+    constructor(prisma: DbClientContract, model: string, options: InternalEnhancementOptions) {
+        super(prisma, model, options);
 
-const decryptFunc = async (encryptedData: string, secret: string): Promise<string> => {
-    const key = await getKey(secret);
+        this.queryUtils = new QueryUtils(prisma, options);
+    }
 
-    // Convert base64 back to bytes
-    const bytes = Uint8Array.from(atob(encryptedData), (c) => c.charCodeAt(0));
+    private isCustomEncryption(encryption: CustomEncryption | SimpleEncryption): encryption is CustomEncryption {
+        return 'encrypt' in encryption && 'decrypt' in encryption;
+    }
 
-    // First 12 bytes are IV, rest is encrypted data
-    const decrypted = await crypto.subtle.decrypt(
-        {
-            name: 'AES-GCM',
-            iv: bytes.slice(0, 12),
-        },
-        key,
-        bytes.slice(12)
-    );
+    private async encrypt(field: FieldInfo, data: string): Promise<string> {
+        if (this.isCustomEncryption(this.options.encryption!)) {
+            return this.options.encryption.encrypt(this.model, field, data);
+        }
 
-    return decoder.decode(decrypted);
-};
+        const key = await getKey(this.options.encryption!.encryptionKey);
+        const iv = crypto.getRandomValues(new Uint8Array(12));
 
-class EncryptedHandler extends DefaultPrismaProxyHandler {
-    private queryUtils: QueryUtils;
+        const encrypted = await crypto.subtle.encrypt(
+            {
+                name: 'AES-GCM',
+                iv,
+            },
+            key,
+            encoder.encode(data)
+        );
 
-    constructor(prisma: DbClientContract, model: string, options: InternalEnhancementOptions) {
-        super(prisma, model, options);
+        // Combine IV and encrypted data into a single array of bytes
+        const bytes = [...iv, ...new Uint8Array(encrypted)];
 
-        this.queryUtils = new QueryUtils(prisma, options);
+        // Convert bytes to base64 string
+        return btoa(String.fromCharCode(...bytes));
+    }
+
+    private async decrypt(field: FieldInfo, data: string): Promise<string> {
+        if (this.isCustomEncryption(this.options.encryption!)) {
+            return this.options.encryption.decrypt(this.model, field, data);
+        }
+
+        const key = await getKey(this.options.encryption!.encryptionKey);
+
+        // Convert base64 back to bytes
+        const bytes = Uint8Array.from(atob(data), (c) => c.charCodeAt(0));
+
+        // First 12 bytes are IV, rest is encrypted data
+        const decrypted = await crypto.subtle.decrypt(
+            {
+                name: 'AES-GCM',
+                iv: bytes.slice(0, 12),
+            },
+            key,
+            bytes.slice(12)
+        );
+
+        return decoder.decode(decrypted);
     }
 
     // base override
@@ -115,9 +135,7 @@ class EncryptedHandler extends DefaultPrismaProxyHandler {
 
             const shouldDecrypt = fieldInfo.attributes?.find((attr) => attr.name === '@encrypted');
             if (shouldDecrypt) {
-                const descryptSecret = shouldDecrypt.args.find((arg) => arg.name === 'secret')?.value as string;
-
-                entityData[field] = await decryptFunc(entityData[field], descryptSecret);
+                entityData[field] = await this.decrypt(fieldInfo, entityData[field]);
             }
         }
     }
@@ -131,7 +149,7 @@ class EncryptedHandler extends DefaultPrismaProxyHandler {
 
                     const secret: string = encAttr.args.find((arg) => arg.name === 'secret')?.value as string;
 
-                    context.parent[field.name] = await encryptFunc(data, secret);
+                    context.parent[field.name] = await this.encrypt(field, data);
                 }
             },
         });