os: fix netmask format check condition in getCIDR function

[HBSPS]

Modified to check the format of the netmask instead of just checking that each part of the netmask is even number.
(Ref: https://www.rfc-editor.org/rfc/rfc1878)

The result of the previous run was like this.

...
if((binary&1)!==0){returnnull;}
...
console.log(getCIDR('127.0.0.1','242.0.0.0','IPv4'));// 127.0.0.1/5// 242 = 11110010(2)

This does not satisfy the condition in netmask, but it passes the conditional statement and returns an invalid value.

I'm not sure if that conditional is necessary(if the correct value is always passed, etc), but I think it's doing the wrong thing, so I've modified it to look like this.

...
if(StringPrototypeIncludes(binary.toString(2),'01')){returnnull;}console.log(getCIDR('127.0.0.1','242.0.0.0','IPv4'));// null
...

I modified the netmask to check if it satisfies the condition of containing '01', such as 11110010, since a 0 cannot be followed by a 1 according to the rules of netmask.

The benchmark results for changing conditions are shown below.

 confidence improvement accuracy (*) (**) (***)
os/networkInterfaces.js n=10000 0.19 % ±1.17% ±1.56% ±2.03%
Be aware that when doing many comparisons the risk of a false-positive result increases.
In this case, there are 1 comparisons, you can thus expect the following amount of false-positive results:
0.05 false positives, when considering a 5% risk acceptance (*, **, ***),
0.01 false positives, when considering a 1% risk acceptance (**, ***),
0.00 false positives, when considering a 0.1% risk acceptance (***)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.22%. Comparing base (db00f94) to head (6e529a4).
Report is 319 commits behind head on main.

Additional details and impacted files

@@ Coverage Diff @@## main #57324 +/- ##
==========================================
+ Coverage 90.20% 90.22% +0.01% 
==========================================
Files 630 630 Lines 185166 185203 +37 Branches 36227 36247 +20 ==========================================
+ Hits 167036 167102 +66 + Misses 11117 11044 -73 - Partials 7013 7057 +44 

Files with missing lines	Coverage Δ
lib/internal/util.js	96.05% <100.00%> (+0.24%)	⬆️
lib/os.js	98.59% <100.00%> (+1.27%)	⬆️

... and 63 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[lpinca]

Can you please add a test?

[HBSPS]

Can you please add a test?

@lpinca This function is only being used by networkInterfaces, which is getting it from internalBinding.

Since networkInterfaces is not a pure function and returns a value based on the current state of the system, is there any way to do mocking or something in this regard?
(I'm not familiar with this kind of testing)

If you have any references or know how to do it, I'd appreciate it :)

functionnetworkInterfaces(){constdata=getInterfaceAddresses();constresult={};if(data===undefined)returnresult;for(leti=0;i<data.length;i+=7){constname=data[i];constentry={address: data[i+1],netmask: data[i+2],family: data[i+3],mac: data[i+4],internal: data[i+5],cidr: getCIDR(data[i+1],data[i+2],data[i+3]),};constscopeid=data[i+6];if(scopeid!==-1)entry.scopeid=scopeid;constexisting=result[name];if(existing!==undefined)ArrayPrototypePush(existing,entry);elseresult[name]=[entry];}returnresult;}

[lpinca]

What do think about moving it to lib/internal/util.js or lib/internal/os/utils.js? The latter does not exist yet.

[HBSPS]

What do think about moving it to lib/internal/util.js or lib/internal/os/utils.js? The latter does not exist yet.

@lpinca Sounds like a good idea, I moved the getCIDR function to internal/util as you said and created a new test file to test that function.

[HBSPS]

@lpinca PR seems to have stopped here, what should I do?

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/66371/ 💛

[nodejs-github-bot]

Commit Queue failed

- Loading data for nodejs/node/pull/57324
✔ Done loading data for nodejs/node/pull/57324
----------------------------------- PR info ------------------------------------
Title os: fix netmask format check condition in getCIDR function (#57324)
Author Wiyeong Seo <wiyeong79@gmail.com> (@HBSPS)
Branch HBSPS:os-getCIDR -> nodejs:main
Labels os, needs-ci
Commits 2
- os: fix netmask format check condition in getCIDR function
- test: move getCIDR function to internal/util and add test code
Committers 1
- HBSPS <wiyeong79@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/57324
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
------------------------------ Generated metadata ------------------------------
PR-URL: https://github.com/nodejs/node/pull/57324
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
--------------------------------------------------------------------------------
ℹ This PR was created on Wed, 05 Mar 2025 02:44:05 GMT
✔ Approvals: 2
✔ - Luigi Pinca (@lpinca): https://github.com/nodejs/node/pull/57324#pullrequestreview-2669497839
✔ - James M Snell (@jasnell) (TSC): https://github.com/nodejs/node/pull/57324#pullrequestreview-2780071018
✔ Last GitHub CI successful
ℹ Last Full PR CI on 2025-04-19T21:27:46Z: https://ci.nodejs.org/job/node-test-pull-request/66371/
- Querying data for job/node-test-pull-request/66371/
✔ Last Jenkins CI successful
--------------------------------------------------------------------------------
✔ No git cherry-pick in progress
✔ No git am in progress
✔ No git rebase in progress
--------------------------------------------------------------------------------
- Bringing origin/main up to date...
From https://github.com/nodejs/node
* branch main -> FETCH_HEAD
✔ origin/main is now up-to-date
- Downloading patch for 57324
From https://github.com/nodejs/node
* branch refs/pull/57324/merge -> FETCH_HEAD
✔ Fetched commits as 25842c5e35ef..6e529a46153e
--------------------------------------------------------------------------------
[main c2a5b7fda5] os: fix netmask format check condition in getCIDR function
Author: HBSPS <wiyeong79@gmail.com>
Date: Tue Mar 4 20:27:46 2025 -0600
1 file changed, 2 insertions(+), 1 deletion(-)
Auto-merging lib/internal/util.js
[main dd12864109] test: move getCIDR function to internal/util and add test code
Author: HBSPS <wiyeong79@gmail.com>
Date: Sun Mar 9 13:36:08 2025 -0500
3 files changed, 81 insertions(+), 56 deletions(-)
create mode 100644 test/parallel/test-internal-util-getCIDR.js
✔ Patches applied
There are 2 commits in the PR. Attempting autorebase.
Rebasing (2/4)
Executing: git node land --amend --yes
--------------------------------- New Message ----------------------------------
os: fix netmask format check condition in getCIDR function
Modified to check the format of the netmask instead

of just checking that each part of the netmask is even
PR-URL: #57324

Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Reviewed-By: James M Snell <jasnell@gmail.com>
[detached HEAD 6933aa3823] os: fix netmask format check condition in getCIDR function

Author: HBSPS <wiyeong79@gmail.com>

Date: Tue Mar 4 20:27:46 2025 -0600

1 file changed, 2 insertions(+), 1 deletion(-)

Rebasing (3/4)

Rebasing (4/4)

Executing: git node land --amend --yes

--------------------------------- New Message ----------------------------------

test: move getCIDR function to internal/util and add test code
move to util/internal and add getCIDR function test file

to test the getCIDR function and added test code for the part

that checks the format of the subnetmask
PR-URL: #57324

Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Reviewed-By: James M Snell <jasnell@gmail.com>
[detached HEAD a054662fbd] test: move getCIDR function to internal/util and add test code

Author: HBSPS <wiyeong79@gmail.com>

Date: Sun Mar 9 13:36:08 2025 -0500

3 files changed, 81 insertions(+), 56 deletions(-)

create mode 100644 test/parallel/test-internal-util-getCIDR.js

Successfully rebased and updated refs/heads/main.
ℹ Add commit-queue-squash label to land the PR as one commit, or commit-queue-rebase to land as separate commits.

https://github.com/nodejs/node/actions/runs/14556471756

[nodejs-github-bot]

Landed in 7102ea1