Re: [key4.db] IV size for aes256-CBC
Louis Abraham via dev-tech-crypto <[email protected]>
| Newsgroups | gmane.comp.mozilla.crypto |
|---|---|
| Message-ID | <CAPdmES8nheU-WVFXF_aLMGp0U1O1a1-GQcmh3HVYaY3z4n61xw@mail.gmail.com> |
Hi Matthew, Awesome, thanks and sorry for contacting the wrong list! Since then, I found the answer to the 14 bytes question: https://hg.mozilla.org/projects/nss/rev/fc636973ad06392d11597620b602779b4af312f6#l6.49 Basically the DER encoding is used instead for compatibility with a bugged implementation. I tried prepending b'\x04\x0e' to DER-encode the IV. However, the value I get makes no sense (and even has an incorrect padding according to pkcs7 <https://tools.ietf.org/html/rfc2315>). Best, Louis Le ven. 27 mars 2020 à 19:57, Matthew N. <[email protected]> a écrit : > Hi Louis, > > The dev-tech-crypto mailing list I'm redirecting this to should be able to > get you an answer. > > Thanks, > MattN > > > On Fri, Mar 27, 2020 at 8:51 AM Louis Abraham <[email protected]> > wrote: > >> Hi, >> >> I'm the main developer of https://github.com/louisabraham/ffpass >> We are currently trying to accommodate the (not so) recent cryptographic >> changes in key4.db. >> >> If I understand correctly, key4.db contains a table metadata. The value >> item2 defines a cryptographic algorithm in the DER format. >> >> In the latest version of Firefox, this algorithm is PBES2, using >> aes256-CBC as the encryption algorithm. >> >> I'm facing a little problem when trying to execute aes256-CBC because the >> IV size is only 14 bytes (56 bits) instead of the 64 bits defined in the >> spec. >> >> Could you please help me to understand? >> >> Best, >> Louis >> > -- dev-tech-crypto mailing list [email protected] https://lists.mozilla.org/listinfo/dev-tech-crypto