From caabe240574aec05b2f5667414ce80f9075c2ba1 Mon Sep 17 00:00:00 2001 From: David Howells Date: Sat, 20 Oct 2012 01:19:29 +0100 Subject: MODSIGN: Move the magic string to the end of a module and eliminate the search Emit the magic string that indicates a module has a signature after the signature data instead of before it. This allows module_sig_check() to be made simpler and faster by the elimination of the search for the magic string. Instead we just need to do a single memcmp(). This works because at the end of the signature data there is the fixed-length signature information block. This block then falls immediately prior to the magic number. From the contents of the information block, it is trivial to calculate the size of the signature data and thus the size of the actual module data. Signed-off-by: David Howells Signed-off-by: Linus Torvalds --- scripts/sign-file | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'scripts') diff --git a/scripts/sign-file b/scripts/sign-file index d37d1309531e..87ca59d36e7e 100755 --- a/scripts/sign-file +++ b/scripts/sign-file @@ -403,11 +403,11 @@ my $info = pack("CCCCCxxxN", if ($verbose) { print "Size of unsigned module: ", length($unsigned_module), "\n"; - print "Size of magic number : ", length($magic_number), "\n"; print "Size of signer's name : ", length($signers_name), "\n"; print "Size of key identifier : ", length($key_identifier), "\n"; print "Size of signature : ", length($signature), "\n"; print "Size of informaton : ", length($info), "\n"; + print "Size of magic number : ", length($magic_number), "\n"; print "Signer's name : '", $signers_name, "'\n"; print "Digest : $dgst\n"; } @@ -416,11 +416,11 @@ open(FD, ">$dest") || die $dest; binmode FD; print FD $unsigned_module, - $magic_number, $signers_name, $key_identifier, $signature, - $info + $info, + $magic_number ; close FD || die $dest; -- cgit v1.2.1