[tpm2] Fapi_Decrypt using auth value
Anthony Arrascue <AArrascue at neuroloop.de>
| Newsgroups | dev.linux.lists.tpm2 |
|---|---|
| Message-ID | <[email protected]> |
Hello, I am learning about encryption / decryption using Fapi. For that purpose, I create a key using tss2_createkey and use tss2_encrypt / tss2_decrypt (and their Fapi equivalents). tss2_ createkey has the argument -a, --authValue to set up a decryption password. With tss2_encrypt I generate the cipher text. The problem is with the decryption process. When I decrypt with tss2_decrypt I got asked for that authValue. If it is given correctly it decrypts the cipher text. However, Fapi_Decrypt will fail throwing an authorization error. I was wondering how to programmatically enter the authValue? Fapi_Decrypt has no arguments to pass it. Maybe through the FAPI_CONTEXT? Using TPM2-TSS v. 2.4.x TPM2-TOOLS v. 4.X Thank you for any possible help. Best, Anthony Arrascue -------------------------------------- neuroloop GmbH Breisacher Str. 86, 79110 Freiburg, Germany aarrascue(a)neuroloop.de<mailto:aarrascue(a)neuroloop.de> neuroloop.de
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<p class="MsoNormal"><span lang="DE">Hello,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I am learning about encryption / decryption using Fapi.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">For that purpose, I create a key using tss2_createkey and use tss2_encrypt / tss2_decrypt (and their Fapi equivalents).<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">tss2_ createkey has the argument -a, --authValue to set up a decryption password.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">With tss2_encrypt I generate the cipher text.<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">The problem is with the decryption process. When I decrypt with tss2_decrypt I got asked for that authValue. If it is given correctly it decrypts the cipher text. However,
<b>Fapi_Decrypt</b> will fail throwing an authorization error.<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 was wondering how to programmatically enter the authValue? Fapi_Decrypt has no arguments to pass it. Maybe through the FAPI_CONTEXT?<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">Using TPM2-TSS v. 2.4.x<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">TPM2-TOOLS v. 4.X<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">Thank you for any possible help.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Best,<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"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="DE" style="font-size:10.0pt;color:black;mso-fareast-language:DE">Anthony Arrascue<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE" style="font-size:10.0pt;color:black;mso-fareast-language:DE">--------------------------------------<br>
neuroloop GmbH<br>
Breisacher Str. 86, 79110 Freiburg, Germany<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE" style="font-size:10.0pt;color:black;mso-fareast-language:DE"><a href="mailto:[email protected]">[email protected]</a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE" style="font-size:10.0pt;color:black;mso-fareast-language:DE">neuroloop.de<br>
<br>
</span><span lang="EN-GB" style="mso-fareast-language:#2000"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE"><o:p> </o:p></span></p>
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