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Disable SSL Certificate Check: 'unknown certificate lookup failure: 33'

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#2,106 0 comments 4 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
csharp, git
Domain
security

Research direction

Start by reproducing the Windows 10, .NET 8.0 case with LibGit2Sharp v0.30.0, using CloneOptions, FetchOptions.CertificateCheck, and Repository.Clone as shown. Trace the certificate callback and the source of “unknown certificate lookup failure: 33”; done means the reported GitLab clone behavior is understood and the intended certificate-check handling is verified.

Written by the indexing model from the issue text.

Description

I want to disable certificate verification when cloning a repo from GitLab.

The code I am using is:

var options = new CloneOptions();
options.FetchOptions.CredentialsProvider = (_url, _user, _cred) 
    => new UsernamePasswordCredentials 
    { 
        Username = "user", 
        Password = "token"
    };
options.FetchOptions.CertificateCheck += delegate (Certificate certificate, bool valid, string host)
{
    return true;
};
Repository.Clone(cloneUrl, cloneDirectoryPath, options);

But I got this error when cloning:
unknown certificate lookup failure: 33

Version of LibGit2Sharp (release number or SHA1)

v0.30.0

Operating system(s) tested; .NET runtime tested

Windows 10
C# net8.0

Dominant language
C#
Stars
3.5k
Forks
925
PR merge metrics
No merged PRs in 30d

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First steps

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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