ASN.1 code passes uninitialized values around

ASN.1 code passes uninitialized values around

	* asn1_get.c (asn1_get_tag_indef): Stomp on asn1class,
	construction, retlen, and indef, even if we've hit the end of the
	buffer, to avoid passing uninitialized values around.

	* asn1_k_decode.c: Reformat somewhat and add comments to demystify
	things a little.
	(opt_field): Fix to explicitly check for end of subbuf before
	verifying the pre-fetched tag, which may have been stomped on by
	asn1_get_tag_indef() encountering end-of-buffer.

	* krb5_decode.c (opt_field, opt_lenfield): Fix to explicitly check
	for end of subbuf before verifying the pre-fetched tag, which may
	have been stomped on by asn1_get_tag_indef() encountering
	end-of-buffer.

ticket: new
target_version: 1.3

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@14913 dc483132-0cff-0310-8789-dd5450dbe970