[[["เข้าใจง่าย","easyToUnderstand","thumb-up"],["แก้ปัญหาของฉันได้","solvedMyProblem","thumb-up"],["อื่นๆ","otherUp","thumb-up"]],[["ไม่มีข้อมูลที่ฉันต้องการ","missingTheInformationINeed","thumb-down"],["ซับซ้อนเกินไป/มีหลายขั้นตอนมากเกินไป","tooComplicatedTooManySteps","thumb-down"],["ล้าสมัย","outOfDate","thumb-down"],["ปัญหาเกี่ยวกับการแปล","translationIssue","thumb-down"],["ตัวอย่าง/ปัญหาเกี่ยวกับโค้ด","samplesCodeIssue","thumb-down"],["อื่นๆ","otherDown","thumb-down"]],["อัปเดตล่าสุด 2025-07-25 UTC"],[[["\u003cp\u003eThe resource key hash ensures Google can verify the integrity of wrapped encryption keys without needing access to the actual keys.\u003c/p\u003e\n"],["\u003cp\u003eGenerating the hash requires the unwrapped key, resource name, and perimeter ID used during key wrapping.\u003c/p\u003e\n"],["\u003cp\u003eIt utilizes HMAC-SHA256, using the unwrapped key as the key and a concatenation of resource details as data for the hash calculation.\u003c/p\u003e\n"],["\u003cp\u003eThe resource name and perimeter ID need to be UTF-8 encoded strings for the hash generation.\u003c/p\u003e\n"]]],["The core mechanism is generating a resource key hash to verify wrapped encryption key integrity. This involves using HMAC-SHA256 with the unwrapped DEK as the key and a specific concatenation of metadata as data. The metadata consists of \"ResourceKeyDigest:\", the UTF-8 encoded `resource_name`, \":\", and the UTF-8 encoded `perimeter_id`. An example shows generating the hash using `openssl` with a sample `resource_name`, `perimeter_id`, and `unwrapped_dek`.\n"],null,["# Resource key hash\n\nThe resource key hash is a mechanism allowing Google to verify the integrity of\nthe wrapped encryption keys without having access to the keys.\n\nGenerating the resource key hash requires access to the unwrapped key including\nthe DEK, the `resource_name` and the `perimeter_id` specified during the key\nwrapping operation.\n\nWe use the cryptographic function HMAC-SHA256 with `unwrapped_dek` as a key and\nthe concatenation of metadata as data\n`(\"ResourceKeyDigest:\", resource_name, \":\", perimeter_id)`.\nThe `resource_name` and `perimeter_id` should be UTF-8 encoded strings.\n\nFor example, when `resource_name = \"my_resource\"`,\n`perimeter_id = \"my_perimeter\"` and `unwrapped_dek = 0xf00d`, the resource key\nhash is: \n\n echo -n \"ResourceKeyDigest:my_resource:my_perimeter\" | openssl sha256 -mac HMAC -macopt hexkey:f00d -binary"]]
