feat(machine id): Add helpers in ddcommon to fetch the machine UUID l…#2163
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paullegranddc wants to merge 4 commits into
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feat(machine id): Add helpers in ddcommon to fetch the machine UUID l…#2163paullegranddc wants to merge 4 commits into
paullegranddc wants to merge 4 commits into
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…ike the agent # Motivation We are replicating the agent RC client. One of the thing the agent uses is a stable identity for the agent host, decorrelated from the hostname (as it is not available in som platforms). It fetches the UUID using a library (psutils), for which there exists no strict equivalent in rust. This PR adds code that should be feature equal to the agent # Changes * Add new machine_id module in libdd-common * Fetch machine id on different platform
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About This ReportThis report tracks Clippy allow annotations for specific rules, showing how they've changed in this PR. Decreasing the number of these annotations generally improves code quality. |
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🎉 All green!🧪 All tests passed 🎯 Code Coverage (details) 🔗 Commit SHA: d1ddfc2 | Docs | Datadog PR Page | Give us feedback! |
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| &mut hkey, | ||
| ) | ||
| }; | ||
| if status != ERROR_SUCCESS as i32 { |
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On Windows this module fails to type-check because windows-sys 0.52 defines RegOpenKeyExW/RegQueryValueExW as returning WIN32_ERROR (u32), but these checks compare that u32 to ERROR_SUCCESS as i32. Any Windows build of libdd-common that includes this new module will fail before use; compare against ERROR_SUCCESS without the cast here and in the two RegQueryValueExW status checks.
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ekump
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LGTM FWIW. I found the code confusing, so suggested some more comments.
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| pub fn get_machine_id_impl() -> String { | ||
| let access = if cfg!(target_pointer_width = "32") && is_wow64() { |
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nit: Do you need is_wow64()? The agent always does KEY_READ_ | KEY_WOW64_64KEY Won't KEY_WOW64_64KEY be a no-op on 64-bit?
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| // Copyright 2021-Present Datadog, Inc. https://www.datadoghq.com/ | |||
| // SPDX-License-Identifier: Apache-2.0 | |||
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Suggested change
| //! Windows host machine id: reads `MachineGuid` from //! `HKLM\SOFTWARE\Microsoft\Cryptography` via the raw Win32 registry API. | |
| //! | |
| //! `MachineGuid` lives in the 64-bit registry view, so a 32-bit process under | |
| //! WOW64 must pass `KEY_WOW64_64KEY` or it gets redirected to the (empty) | |
| //! `WOW6432Node` copy. The value is read with the standard two-call Win32 | |
| //! pattern: query the byte size, then read into a right-sized buffer. |
| } | ||
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| pub fn get_machine_id_impl() -> String { | ||
| let access = if cfg!(target_pointer_width = "32") && is_wow64() { |
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| let access = if cfg!(target_pointer_width = "32") && is_wow64() { | |
| // MachineGuid is in the 64-bit view; a 32-bit process under WOW64 is | |
| // redirected to WOW6432Node by default, so force the 64-bit view there. | |
| let access = if cfg!(target_pointer_width = "32") && is_wow64() { |
| return String::new(); | ||
| } | ||
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| let mut buf: Vec<u16> = vec![0u16; (data_len as usize).div_ceil(2)]; |
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| let mut buf: Vec<u16> = vec![0u16; (data_len as usize).div_ceil(2)]; | |
| // data_len is bytes; REG_SZ holds UTF-16, so the u16 count is bytes/2 (round up). | |
| let mut buf: Vec<u16> = vec![0u16; (data_len as usize).div_ceil(2)]; |
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| let mut data_type: u32 = 0; | ||
| let mut data_len: u32 = 0; | ||
| // SAFETY: null data pointer is valid for a size-query call. |
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| // SAFETY: null data pointer is valid for a size-query call. | |
| // SAFETY: null data pointer is valid for a size-query call. | |
| // First call (null data pointer) returns the value's size in bytes. |
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| // Copyright 2021-Present Datadog, Inc. https://www.datadoghq.com/ | |||
| // SPDX-License-Identifier: Apache-2.0 | |||
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Suggested change
| //! macOS host machine id via `gethostuuid(3)`, returning `IOPlatformUUID`. |
| /// Returns `IOPlatformUUID` via `gethostuuid(3)`, which avoids a fork+exec of `ioreg`. | ||
| pub fn get_machine_id_impl() -> String { | ||
| let mut uuid = [0u8; 16]; | ||
| let wait = libc::timespec { |
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| let wait = libc::timespec { | |
| // Zero timeout: the host UUID is static, so there's nothing to wait for. | |
| let wait = libc::timespec { |
| if rc != 0 { | ||
| return String::new(); | ||
| } | ||
| format!( |
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| format!( | |
| // Assemble the 16 raw bytes into the canonical 8-4-4-4-12 hyphenated UUID. | |
| format!( |
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| // Copyright 2021-Present Datadog, Inc. https://www.datadoghq.com/ | |||
| // SPDX-License-Identifier: Apache-2.0 | |||
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Suggested change
| //! Linux host machine id, mirroring gopsutil's fallback order: | |
| //! `/sys/class/dmi/id/product_uuid` (root-only, usually empty otherwise) → | |
| //! `/etc/machine-id` → `/proc/sys/kernel/random/boot_id`. |
| } | ||
| } | ||
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| pub fn get_machine_id_impl_paths(dmi_path: &Path, etc_path: &Path, boot_path: &Path) -> String { |
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| pub fn get_machine_id_impl_paths(dmi_path: &Path, etc_path: &Path, boot_path: &Path) -> String { | |
| /// Resolves the id from the three candidate paths in priority order. Paths are | |
| /// parameters so the fallback logic is unit-testable without real `/sys`/`/etc`. | |
| pub fn get_machine_id_impl_paths(dmi_path: &Path, etc_path: &Path, boot_path: &Path) -> String { |
ekump
approved these changes
Jun 25, 2026
ekump
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ekump
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LGTM FWIW. I found the code confusing, so suggested some more comments.
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…ike the agent
Motivation
We are replicating the agent RC client. One of the thing the agent uses is a stable identity for the agent host, decorrelated from the hostname (as it is not available in som platforms).
It fetches the UUID using a library (psutils), for which there exists no strict equivalent in rust.
This PR adds code that should be feature equal to the agent
Changes
What does this PR do?
A brief description of the change being made with this pull request.
Motivation
What inspired you to submit this pull request?
Additional Notes
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How to test the change?
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