Commit Graph

6 Commits

Author SHA1 Message Date
David Howells 98801c002f pefile: Validate PKCS#7 trust chain
Validate the PKCS#7 trust chain against the contents of the system keyring.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
2014-07-09 14:58:47 +01:00
David Howells af316fc442 pefile: Digest the PE binary and compare to the PKCS#7 data
Digest the signed parts of the PE binary, canonicalising the section table
before we need it, and then compare the the resulting digest to the one in the
PKCS#7 signed content.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00
David Howells 4c0b4b1d1a pefile: Parse the "Microsoft individual code signing" data blob
The PKCS#7 certificate should contain a "Microsoft individual code signing"
data blob as its signed content.  This blob contains a digest of the signed
content of the PE binary and the OID of the digest algorithm used (typically
SHA256).

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00
David Howells 3968280c76 pefile: Parse the presumed PKCS#7 content of the certificate blob
Parse the content of the certificate blob, presuming it to be PKCS#7 format.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00
David Howells 09dacbbda9 pefile: Strip the wrapper off of the cert data block
The certificate data block in a PE binary has a wrapper around the PKCS#7
signature we actually want to get at.  Strip this off and check that we've got
something that appears to be a PKCS#7 signature.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00
David Howells 26d1164be3 pefile: Parse a PE binary to find a key and a signature contained therein
Parse a PE binary to find a key and a signature contained therein.  Later
patches will check the signature and add the key if the signature checks out.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2014-07-09 14:58:37 +01:00