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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I would like to have my understanding of the following issue confirmed:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Given a two-level CA where the different generations of Root cross-sign each other, the verification of an end-entity certificate fails with OpenSSL 1.1.1 – “path length constraint exceeded”. With OpenSSL 1.0.2 the same
verify succeeds.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">All Root CA certificates have Basic Constraints CA:TRUE, pathlen:1. The Sub CA certificate has pathlen:0.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">A) Issuer: CN=Root CA, serialNumber=1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> Subject: CN=Root CA, serialNumber=1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">B) Issuer: CN=Root CA, serialNumber=2<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> Subject: CN=Root CA, serialNumber=2<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">C) Issuer: CN=Root CA, serialNumber=1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> Subject: CN=Root CA, serialNumber=2<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">D) Issuer: CN=Root CA, serialNumber=2<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> Subject: CN=Sub CA, serialNumber=2<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">E) Issuer: CN=Sub CA, serialNumber=2<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> Subject: Some end entity<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">With a CAfile containing D, C, B, A in that order the verify of E fails. If I remove the cross certificate C then the verify succeeds.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I believe OpenSSL 1.1.1 is building a chain of depth 3 (D – C – A) and so pathlen:1 of A is violated. Without the cross certificate the chain is only depth 2 (D – B).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Is my understanding of the reason for this failure correct?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Why is OpenSSL 1.0.2 verifying successfully? Does it not check the path length constraint or is it actually picking the depth 2 chain instead of the depth 3?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Andrew.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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