Add JWT generation for API server authentication

CMakeLists.txt

@@ -75,6 +75,13 @@ FetchContent_Declare(
   GIT_TAG v1.14.0
 )
 
+# jwt-cpp is a header-only JWT library
+FetchContent_Declare(
+  jwt-cpp
+  GIT_REPOSITORY https://github.com/Thalhammer/jwt-cpp.git
+  GIT_TAG master
+)
+
 # Fetch dependencies
 
 # Disable dependency tests for cppcodec
@@ -85,7 +92,7 @@ set(BUILD_TESTING OFF CACHE BOOL "" FORCE)
 FetchContent_MakeAvailable(cppcodec)
 set(BUILD_TESTING ON CACHE BOOL "" FORCE)
 
-FetchContent_MakeAvailable(crow httplib nlohmann_json cxxopts googletest)
+FetchContent_MakeAvailable(crow httplib nlohmann_json cxxopts googletest jwt-cpp)
 
 # Make GoogleTest helper macros available (gtest_discover_tests)
 include(GoogleTest)
@@ -109,14 +116,21 @@ target_link_libraries(dbps_common_lib PUBLIC tcb_span)
 # Server components library
 add_library(dbps_server_lib STATIC 
   src/server/encryption_sequencer.cpp
+  src/server/auth_utils.cpp
   src/server/decoding_utils.cpp
 )
 target_link_libraries(dbps_server_lib PUBLIC dbps_common_lib)
 target_include_directories(dbps_server_lib PUBLIC
   src/server
   ${CMAKE_BINARY_DIR}/_deps/cppcodec-src
+  ${CMAKE_BINARY_DIR}/_deps/jwt-cpp-src/include
+  ${CMAKE_BINARY_DIR}/_deps/nlohmann_json-src/include
 )
 
+# Find and link OpenSSL (required by jwt-cpp)
+find_package(OpenSSL REQUIRED)
+target_link_libraries(dbps_server_lib PUBLIC OpenSSL::SSL OpenSSL::Crypto)
+
 # Client components library (depends on httplib, nlohmann/json, and cppcodec)
 add_library(dbps_client_lib STATIC 
   src/client/dbps_api_client.cpp
@@ -229,6 +243,15 @@ if(BUILD_TESTS)
   )
   target_include_directories(decoding_utils_test PRIVATE src/server)
 
+  # Auth utils tests
+  add_executable(auth_utils_test src/server/auth_utils_test.cpp)
+  target_link_libraries(auth_utils_test
+    dbps_server_lib
+    dbps_common_lib
+    gtest_main
+  )
+  target_include_directories(auth_utils_test PRIVATE src/server)
+
   # DBPA interface tests
   add_executable(dbpa_interface_test src/common/dbpa_interface_test.cpp)
   target_link_libraries(dbpa_interface_test
@@ -389,6 +412,7 @@ if(BUILD_TESTS)
       enum_utils_test
       encryption_sequencer_test
       decoding_utils_test
+      auth_utils_test
       dbpa_interface_test
       dbpa_utils_test
       dbps_api_client_test
@@ -404,6 +428,7 @@ if(BUILD_TESTS)
   gtest_discover_tests(enum_utils_test)
   gtest_discover_tests(encryption_sequencer_test)
   gtest_discover_tests(decoding_utils_test)
+  gtest_discover_tests(auth_utils_test)
   gtest_discover_tests(dbpa_interface_test)
   gtest_discover_tests(dbpa_utils_test)
   gtest_discover_tests(dbps_api_client_test)

src/server/auth_utils.cpp

@@ -0,0 +1,175 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+#include "auth_utils.h"
+#include <jwt-cpp/jwt.h>
+#include <chrono>
+#include <iostream>
+#include <fstream>
+#include <nlohmann/json.hpp>
+
+// Hardcoded JWT secret key for signing tokens
+// TODO: Make this configurable (e.g., from environment variable or config file)
+static const std::string JWT_SECRET_KEY = "default-secret-key-change-in-production";
+
+// JWT expiration time: 4 hours in seconds
+static const int JWT_EXPIRATION_SECONDS = 4 * 60 * 60;  // 14400 seconds
+
+// ClientCredentialStore implementation
+
+// Initialize credential store from a given map.
+void ClientCredentialStore::init(const std::map<std::string, std::string>& credentials) {
+    credentials_.clear();
+    credentials_ = credentials;
+}
+
+// Initialize credential store from a JSON file
+bool ClientCredentialStore::init(const std::string& file_path) {
+    try {
+        // Open and read the JSON file
+        std::ifstream file(file_path);
+        if (!file.is_open()) {
+            std::cerr << "Error: Cannot open credentials file: " << file_path << std::endl;
+            return false;
+        }
+
+        // Parse JSON
+        nlohmann::json json_data;
+        file >> json_data;
+        file.close();
+
+        // Validate that it's an object
+        if (!json_data.is_object()) {
+            std::cerr << "Error: Credentials file must contain a JSON object" << std::endl;
+            return false;
+        }
+
+        // Clear existing credentials
+        credentials_.clear();
+
+        // Load each client_id:api_key pair
+        for (auto& [client_id, api_key_value] : json_data.items()) {
+            if (api_key_value.is_string()) {
+                AddCredential(client_id, api_key_value.get<std::string>());
+            } else {
+                std::cerr << "Warning: Skipping invalid api_key for client_id: " << client_id << std::endl;
+            }
+        }
+
+        return true;
+    } catch (const nlohmann::json::exception& e) {
+        std::cerr << "Error parsing JSON credentials file: " << e.what() << std::endl;
+        return false;
+    } catch (const std::exception& e) {
+        std::cerr << "Error loading credentials file: " << e.what() << std::endl;
+        return false;
+    }
+}
+
+void ClientCredentialStore::AddCredential(const std::string& client_id, const std::string& api_key) {
+    credentials_[client_id] = api_key;
+}
+
+bool ClientCredentialStore::ValidateCredential(const std::string& client_id, const std::string& api_key) const {
+    auto it = credentials_.find(client_id);
+    if (it == credentials_.end()) {
+        return false;
+    }
+    return it->second == api_key;
+}
+
+bool ClientCredentialStore::HasClientId(const std::string& client_id) const {
+    return credentials_.find(client_id) != credentials_.end();
+}
+
+// GenerateJWT implementation
+std::optional<std::string> ClientCredentialStore::GenerateJWT(const std::string& client_id, const std::string& api_key) const {
+    // Validate that client_id is not empty
+    if (client_id.empty()) {
+        std::cerr << "Error generating JWT: client_id cannot be empty" << std::endl;
+        return std::nullopt;
+    }
+
+    // Validate credentials before generating JWT
+    if (!ValidateCredential(client_id, api_key)) {
+        std::cerr << "Error generating JWT: Invalid credentials for client_id: " << client_id << std::endl;
+        return std::nullopt;
+    }
+
+    try {
+        // Get current time
+        auto now = std::chrono::system_clock::now();
+        auto now_seconds = std::chrono::duration_cast<std::chrono::seconds>(now.time_since_epoch()).count();
+
+        // Calculate expiration time (4 hours from now)
+        auto exp_seconds = now_seconds + JWT_EXPIRATION_SECONDS;
+
+        // Create JWT token with client_id, iat, and exp claims
+        auto token = jwt::create()
+            .set_type("JWT")
+            .set_payload_claim("client_id", jwt::claim(client_id))
+            .set_issued_at(std::chrono::system_clock::from_time_t(now_seconds))
+            .set_expires_at(std::chrono::system_clock::from_time_t(exp_seconds))
+            .sign(jwt::algorithm::hs256{JWT_SECRET_KEY});
+
+        return token;
+    } catch (const std::exception& e) {
+        std::cerr << "Error generating JWT: " << e.what() << std::endl;
+        return std::nullopt;
+    }
+}
+
+// ParseAuthRequest implementation
+AuthRequest ParseAuthRequest(const std::string& request_body) {
+    AuthRequest auth_req;
+
+    try {
+        // Parse JSON request body using nlohmann::json
+        nlohmann::json json_body = nlohmann::json::parse(request_body);
+
+        // Validate that it's an object
+        if (!json_body.is_object()) {
+            auth_req.error_message = "Invalid JSON in request body";
+            return auth_req;
+        }
+
+        // Extract client_id from request
+        if (json_body.contains("client_id") && json_body["client_id"].is_string()) {
+            auth_req.client_id = json_body["client_id"].get<std::string>();
+        } else {
+            auth_req.error_message = "Missing required field: client_id";
+            return auth_req;
+        }
+
+        // Extract api_key from request
+        if (json_body.contains("api_key") && json_body["api_key"].is_string()) {
+            auth_req.api_key = json_body["api_key"].get<std::string>();
+        } else {
+            auth_req.error_message = "Missing required field: api_key";
+            return auth_req;
+        }
+
+        return auth_req;
+    } catch (const nlohmann::json::exception& e) {
+        auth_req.error_message = "Invalid JSON in request body: " + std::string(e.what());
+        return auth_req;
+    } catch (const std::exception& e) {
+        auth_req.error_message = "Error parsing request: " + std::string(e.what());
+        return auth_req;
+    }
+}
+

src/server/auth_utils.h

@@ -0,0 +1,105 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+// Note for Protegrity integration:
+// - This is a simplified Authentication module used to complete the client integration.
+// - It is fully functional, but for production deployment a fully fledged Identity Provider can be used instead.
+//
+// TODO: Expand explanation below.
+// - Note that no Arrow codebase changes would be needed to replace this with a fully fledged Identity Provider
+//   as the connection configuration specified on the application level is passed as-is to the DBPS agents for authentication.
+
+#pragma once
+
+#include <map>
+#include <string>
+#include <optional>
+
+#ifndef DBPS_EXPORT
+#define DBPS_EXPORT
+#endif
+
+/**
+ * ClientCredentialStore manages client_id to api_key mappings for authentication.
+ * 
+ * - Loads client credentials from a Json file and stores them in-memory.
+ * - Generates a JWT token for a given client_id.
+ */
+class DBPS_EXPORT ClientCredentialStore {
+public:
+    ClientCredentialStore() = default;
+    ~ClientCredentialStore() = default;
+
+    /**
+     * Initializes the credential store by loading credentials from a JSON file.
+     * The file should contain a JSON object with client_id as keys and api_key as values.
+     * Example format: {"client1": "api_key_1", "client2": "api_key_2"}
+     */
+    bool init(const std::string& file_path);
+
+    /**
+     * Initializes the credential store with a pre-built map of client_id to api_key.
+     * @param credentials Map of client_id to api_key pairs
+     */
+    void init(const std::map<std::string, std::string>& credentials);
+
+    /**
+     * Generates a JWT token for the given client_id if the credentials are valid.
+     * 
+     * The JWT includes:
+     * - client_id: The client identifier
+     * - iat: Issued at timestamp
+     * - exp: Expiration timestamp (4 hours from issue time)
+     * 
+     * Uses HS256 algorithm with a hardcoded secret key.
+     * 
+     * @param client_id The client identifier to validate and include in the JWT
+     * @param api_key The API key to validate against the stored credential
+     * @return The JWT token as a string if credentials are valid, or std::nullopt on error or invalid credentials
+     */
+    std::optional<std::string> GenerateJWT(const std::string& client_id, const std::string& api_key) const;
+
+private:
+    // Adds a client credential to the in-memory storage.
+    void AddCredential(const std::string& client_id, const std::string& api_key);
+
+    // Check if a client credential is valid before generating a JWT token.
+    bool ValidateCredential(const std::string& client_id, const std::string& api_key) const;
+
+    // Check if a a credential for a client_id exists
+    bool HasClientId(const std::string& client_id) const;
+
+    // In-memory storage: client_id -> api_key
+    std::map<std::string, std::string> credentials_;
+};
+
+/**
+ * Structure to hold parsed authentication request data.
+ */
+struct DBPS_EXPORT AuthRequest {
+    std::string client_id;
+    std::string api_key;
+    std::optional<std::string> error_message;  // Error message if parsing failed
+};
+
+/**
+ * Parses an authentication request from JSON body.
+ * 
+ * @param request_body The raw JSON request body string
+ * @return AuthRequest struct with parsed client_id and api_key, or error_message if parsing failed
+ */
+DBPS_EXPORT AuthRequest ParseAuthRequest(const std::string& request_body);