X-Git-Url: https://git.saurik.com/apple/security.git/blobdiff_plain/5dd5f9ec28f304ca377c42fd7f711d6cf12b90e1..5c19dc3ae3bd8e40a9c028b0deddd50ff337692c:/Security/libsecurity_cdsa_utilities/lib/acl_comment.cpp diff --git a/Security/libsecurity_cdsa_utilities/lib/acl_comment.cpp b/Security/libsecurity_cdsa_utilities/lib/acl_comment.cpp deleted file mode 100644 index 8cf7501f..00000000 --- a/Security/libsecurity_cdsa_utilities/lib/acl_comment.cpp +++ /dev/null @@ -1,156 +0,0 @@ -/* - * Copyright (c) 2000-2006,2011-2012,2014 Apple Inc. All Rights Reserved. - * - * @APPLE_LICENSE_HEADER_START@ - * - * This file contains Original Code and/or Modifications of Original Code - * as defined in and that are subject to the Apple Public Source License - * Version 2.0 (the 'License'). You may not use this file except in - * compliance with the License. Please obtain a copy of the License at - * http://www.opensource.apple.com/apsl/ and read it before using this - * file. - * - * The Original Code and all software distributed under the License are - * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER - * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, - * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. - * Please see the License for the specific language governing rights and - * limitations under the License. - * - * @APPLE_LICENSE_HEADER_END@ - */ - - -// -// acl_comment - "ignore" ACL subject type. -// -// CommentAclSubjects were a bad idea, badly implemented. The code below -// exists solely to keep existing (external) ACL forms from blowing up the -// ACL reader machinery and crashing the evaluation host. -// The original serialization code was not architecture independent - for either -// pointer sizes(!) or byte ordering. Yes, that was a stupid mistake. -// The following code is intentionally, wilfully violating the layer separation -// of the ACL reader/writer machine to deduce enough information about the -// originating architecture to cleanly consume (just) the bytes making up this -// ACL's external representation. We make no use of the bytes read; thankfully, -// the semantics of a CommentAclSubject have always been "never matches." -// We do not preserve them on write-out; a newly-written ACL will contain no data -// (and will read cleanly). -// If you use this code as a template for anything (other than a how-not-to-write-code -// seminar), your backups shall rot right after your main harddrive crashes, and -// you have only yourself to blame. -// -#include -#include -#include -#include - -using namespace DataWalkers; - - -// -// The COMMENT subject matches nothing, no matter how pretty. -// -bool CommentAclSubject::validate(const AclValidationContext &) const -{ - return false; -} - - -// -// The list form has no values. -// -CssmList CommentAclSubject::toList(Allocator &alloc) const -{ - return TypedList(Allocator::standard(), CSSM_ACL_SUBJECT_TYPE_COMMENT); -} - - -// -// We completely disregard any data contained in CSSM form COMMENT ACLs. -// -CommentAclSubject *CommentAclSubject::Maker::make(const TypedList &list) const -{ - return new CommentAclSubject(); -} - - -// -// This is the nasty code. We don't really care what data was originally baked -// into this ACL's external (stream) form, but since there's no external framing -// to delimit it, we need to figure out how many bytes to consume to keep the -// reader from going out of sync. And that's not pretty, since the external form -// contains (stupidly!) a pointer, so we have all permutations of byte order and -// pointer size to worry about. -// -CommentAclSubject *CommentAclSubject::Maker::make(Version, Reader &pub, Reader &) const -{ - // - // At this point, the Reader is positioned at data that was once written using - // this code: - // pub(ptr); // yes, that's a pointer - // pub.countedData(ptr, size); - // We know ptr was a non-NULL pointer (4 or 8 bytes, alas). - // CountedData writes a 4-byte NBO length followed by that many bytes. - // The data written starts with a CSSM_LIST structure in native architecture. - // That in turn begins with a CSSM_LIST_TYPE (4 bytes, native, 0<=type<=2). - // So to summarize (h=host byte order, n=network byte order), we might be looking at: - // 32 bits: | P4h | L4n | T4h | (L-4 bytes) | - // 64 bits: | P8h | L4n | (L bytes) | - // It's the T4h-or-L4n bytes that save our day, since we know that - // 0 <= T <= 2 (definition of CSSM_LIST_TYPE) - // 16M > L >= sizeof(CSSM_LIST) >= 12 - // Phew. I'd rather be lucky than good... - // - // So let's get started: -#ifndef NDEBUG - static const size_t minCssmList = 12; // min(sizeof(CSSM_LIST)) of all architectures -#endif - pub.get(4); // skip first 4 bytes - uint32_t lop; pub(lop); // read L4n-or-(bottom of)P8h - uint32_t tol; pub(tol); // read T4h-or-L4n - if (tol <= 2 || flip(tol) <= 2) { // 32 bits - // the latter can't be a very big (flipped) L because we know 12 < L < 16M, - // and you'd have to be a multiple of 2^24 to pass that test - size_t length = n2h(lop); - assert(length >= minCssmList); - pub.get(length - sizeof(tol)); // skip L-4 bytes - } else { // 64 bits - size_t length = n2h(tol); - assert(length >= minCssmList); - pub.get(length); // skip L bytes - } - - // we've successfully thrown out the garbage. What's left is a data-less subject - return new CommentAclSubject(); // no data -} - - -// -// Export to blob form. -// This simply writes the smallest form consistent with the heuristic above. -// -void CommentAclSubject::exportBlob(Writer::Counter &pub, Writer::Counter &) -{ - uint32_t zero = 0; - Endian length = 12; - pub(zero); pub(length); pub(zero); pub(zero); pub(zero); -} - -void CommentAclSubject::exportBlob(Writer &pub, Writer &) -{ - uint32_t zero = 0; - Endian length = 12; - pub(zero); pub(length); pub(zero); pub(zero); pub(zero); -} - - -#ifdef DEBUGDUMP - -void CommentAclSubject::debugDump() const -{ - Debug::dump("Comment[never]"); -} - -#endif //DEBUGDUMP