[openssl-dev] [openssl.org #3927] regression in 1.0.2c spotted by Net-SSLeay

[Stephen Henson via RT]

On Mon Jun 29 14:27:18 2015, meissner at suse.de wrote:
> Hi,
>
> I am debugging a testsuite error in the perl Net-SSLeay module, which
> got introduced between 1.0.2a
> and 1.0.2c.
>
> The test code looks like this:
>
> ... private key in $pk ...
>
> ok(my $alg2 = Net::SSLeay::EVP_get_cipherbyname("DES-EDE3-OFB"),
> "EVP_get_cipherbyname");
> like(my $key_pem4 =
> Net::SSLeay::PEM_get_string_PrivateKey($pk,"password",$alg2), qr/-----
> BEGIN (ENCRYPTED|RSA) PRIVATE KEY-----/,
> "PEM_get_string_PrivateKey+passwd+enc_alg");
>
> Previously it returned a encrypted key, now it does not.
>
> The error stack has:
> 0:error:0D0A706C:asn1 encoding
> routines:PKCS5_pbe2_set_iv:cipher has no object
> identifier:p5_pbev2.c:104:
> 0:error:2307D00D:PKCS12 routines:PKCS8_encrypt:ASN1
> lib:p12_p8e.c:86:
>
[snip]
>
> which comes from the objects entry:
> obj_dat.h:{"DES-EDE3-CBC","des-ede3-
> cbc",NID_des_ede3_cbc,8,&(lvalues[235]),0},
> obj_dat.h:{"DES-EDE3-OFB","des-ede3-ofb",NID_des_ede3_ofb64,0,NULL,0},
>
> I was not able to find out why des-ede3-cbc does have length 8, but
> ofb does not?
>
> How to fix this? Should it have length 8 too?
>

That should never have worked in the first place. It has a length 0 because the
NID has no corresponding object identifier and such NIDs cannot be properly
encoded in PKCS#8 format. The fact that OpenSSL let you do that previously
(with a garbage OID) is the bug.

The fix is to use a cipher mode which is properly supported for PKCS#8 format
such as CBC mode.

Steve.
--
Dr Stephen N. Henson. OpenSSL project core developer.
Commercial tech support now available see: http://www.openssl.org