Hi Dave,
Thank you for the detailed explanation and the suggestions. It really helped
to solve the issue.

I did use openssl tool to avoid the problem. I tried clearing the keyid and
friendly name in cert using x509_xxxx_set1 fn's
before passing it to PKCS12_create and it also worked fine. I was not aware
of these api's to clear the attribute fields.
So another option i tried was by creating my own PKCS12 parse function and
removed the keyid attribute setting in cert.

Your assumption about my code snippet is right. I just provided the relevant
functions that are actually from two different functions
in my code. So fp handling is fine. Also thanks for pointing out the
discrepancy in encryption algorithm passed to PKCS12_create function.

-Shafeek

On Tue, Feb 1, 2011 at 3:01 AM, Dave Thompson <dthomp...@prinpay.com> wrote:

> >       From: owner-openssl-us...@openssl.org On Behalf Of Muhammed
> Shafeek
> >       Sent: Wednesday, 26 January, 2011 12:30
>
> >       I've a program that extracts private key and cert from the input
> > pfx file loaded into the system
> >       and then create a p12 file out of this private key and cert using
> > a different password to add it to a local keystore.
>
> You know you could use the commandline utility to do this.
> (Given it is present, or can be installed, and accessible;
> and you can write some temporary files, but if you can write
> an output file you can probably do temporaries.)
>
> >       /*code to extract key*/
> >       p12Key = d2i_PKCS12_fp(fp, NULL);
> >       PKCS12_parse(p12Key, pass, pkey, NULL, NULL);
>
> >       /*code to extract cert*/
> >       p12Cert = d2i_PKCS12_fp(fp, NULL);
> >       PKCS12_parse(p12Cert, pass, NULL, pCert, NULL);
>
> I assume you've omitted some file-management code here,
> since two d2i's from the same file open (fp) don't work.
> And you don't need them; you could call PKCS12_parse twice
> on a single (decoded) p12 object. But you shouldn't;
> one call to PKCS12_parse can get both key and cert,
> and should since they logically (must) go together.
>
> And you should definitely check for error(s), but I'll
> optimistically assume that was just omitted for posting.
>
> >       /*creating p12 from the extracted key and cert*/
> >       p12 = PKCS12_create(password, name, pkey, pCert, NULL,
> > NID_pbe_WithSHA1And40BitRC4,NID_pbe_WithSHA1And3_Key_TripleDES_CBC,0, 0,
> 0);
>
> It makes no security sense to encrypt the key with RC4-40,
> which nowadays is trivially brute-forced (even in the days
> of ITAR when PKCS12 was established, it was pretty easy),
> but the cert which doesn't really need privacy with TripleDES.
> The defaults, which are the other way, would be much better.
>
> >       I observe the following things:
> >       1. The attributes ptr in pkey extracted using PKCS12_parse is null.
> > Note that the input pfx does have local Key ID and friendly name.
> > The cert extracted using PKCS12_parse
> >       have local Key ID attribute which is same as in input pfx file.
>
> Yes, p12_kiss.c returns alias=friendly and keyid for the cert
> and no attributes for the key. The man page says
> > Attributes currently cannot be store in the private key
> >     EVP_PKEY structure.
> although that appears to be out of date.
> Perhaps it should, although friendly and keyid should be the same
> for key and cert if used at all, so getting them on the cert
> should probably usually be enough.
>
> >       2. The p12 file created using PKCS12_create has a local KeyID
> > attribute for private key and is different from that of cert.
>
> I assume you mean PKCS12_create plus i2d_PKCS12_fp or similar,
> since PKCS12_create by itself only creates a memory structure.
>
> >       Can any one please explain the reason for this? Is there any issue
> > in my code? or Is this an openssl issue?
>
> On the cert, p12_crt.c uses any friendly=alias and keyid
> in the cert object, and ADDS friendly from caller if not null
> and keyid = SHA1 of cert (if doing both key&cert).
> This appears to violate PKCS9 (at least the one I have)
> which says single-valued. And isn't mentioned on the man page.
> (On the key, it just does friendly from caller and keyid = SHA1,
> but also MSCSPname and recently LocalKeySet from key.attributes!)
> Depending on the software that reads this, if it assumes
> the PKCS9 single-value rule as it apparently has a right to,
> which values get used/displayed/whatever for the cert
> may be arbitrary or even unpredictable.
>
> You probably should X509_alias_set1(,NULL,0) and similarly
> for keyid on your cert before giving it to PKCS12_create.
>
> Alternatively, but more work, build your own exactly as you want
> with the PKCS12_ PKCS7_ PKCS8_ etc. primitives.
>
>
>
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