xref: /xnu-8019.80.24/libkern/ptrauth_utils.c (revision a325d9c4a84054e40bbe985afedcb50ab80993ea)
1*a325d9c4SApple OSS Distributions /*
2*a325d9c4SApple OSS Distributions  * Copyright (c) 2020 Apple Inc. All rights reserved.
3*a325d9c4SApple OSS Distributions  *
4*a325d9c4SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*a325d9c4SApple OSS Distributions  *
6*a325d9c4SApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*a325d9c4SApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*a325d9c4SApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
9*a325d9c4SApple OSS Distributions  * compliance with the License. The rights granted to you under the License
10*a325d9c4SApple OSS Distributions  * may not be used to create, or enable the creation or redistribution of,
11*a325d9c4SApple OSS Distributions  * unlawful or unlicensed copies of an Apple operating system, or to
12*a325d9c4SApple OSS Distributions  * circumvent, violate, or enable the circumvention or violation of, any
13*a325d9c4SApple OSS Distributions  * terms of an Apple operating system software license agreement.
14*a325d9c4SApple OSS Distributions  *
15*a325d9c4SApple OSS Distributions  * Please obtain a copy of the License at
16*a325d9c4SApple OSS Distributions  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*a325d9c4SApple OSS Distributions  *
18*a325d9c4SApple OSS Distributions  * The Original Code and all software distributed under the License are
19*a325d9c4SApple OSS Distributions  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*a325d9c4SApple OSS Distributions  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*a325d9c4SApple OSS Distributions  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*a325d9c4SApple OSS Distributions  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*a325d9c4SApple OSS Distributions  * Please see the License for the specific language governing rights and
24*a325d9c4SApple OSS Distributions  * limitations under the License.
25*a325d9c4SApple OSS Distributions  *
26*a325d9c4SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*a325d9c4SApple OSS Distributions  */
28*a325d9c4SApple OSS Distributions 
29*a325d9c4SApple OSS Distributions #include <IOKit/IOLib.h>
30*a325d9c4SApple OSS Distributions #include <kern/debug.h> // for panic()
31*a325d9c4SApple OSS Distributions 
32*a325d9c4SApple OSS Distributions #include <libkern/ptrauth_utils.h>
33*a325d9c4SApple OSS Distributions 
34*a325d9c4SApple OSS Distributions /*
35*a325d9c4SApple OSS Distributions  * On ptrauth systems, ptrauth_utils_sign_blob_generic is implemented
36*a325d9c4SApple OSS Distributions  * in osfmk/arm64/machine_routines_asm.s
37*a325d9c4SApple OSS Distributions  */
38*a325d9c4SApple OSS Distributions 
39*a325d9c4SApple OSS Distributions #if !__has_feature(ptrauth_calls)
40*a325d9c4SApple OSS Distributions ptrauth_generic_signature_t
ptrauth_utils_sign_blob_generic(__unused const void * ptr,__unused size_t len_bytes,__unused uint64_t data,__unused int flags)41*a325d9c4SApple OSS Distributions ptrauth_utils_sign_blob_generic(__unused const void * ptr, __unused size_t len_bytes, __unused uint64_t data, __unused int flags)
42*a325d9c4SApple OSS Distributions {
43*a325d9c4SApple OSS Distributions 	return 0;
44*a325d9c4SApple OSS Distributions }
45*a325d9c4SApple OSS Distributions #endif // __has_feature(ptrauth_calls)
46*a325d9c4SApple OSS Distributions 
47*a325d9c4SApple OSS Distributions 
48*a325d9c4SApple OSS Distributions /*
49*a325d9c4SApple OSS Distributions  * ptrauth_utils_auth_blob_generic
50*a325d9c4SApple OSS Distributions  *
51*a325d9c4SApple OSS Distributions  * Authenticate signature produced by ptrauth_utils_sign_blob_generic
52*a325d9c4SApple OSS Distributions  */
53*a325d9c4SApple OSS Distributions 
54*a325d9c4SApple OSS Distributions #if __has_feature(ptrauth_calls)
55*a325d9c4SApple OSS Distributions __attribute__((noinline))
56*a325d9c4SApple OSS Distributions void
ptrauth_utils_auth_blob_generic(const void * ptr,size_t len_bytes,uint64_t data,int flags,ptrauth_generic_signature_t signature)57*a325d9c4SApple OSS Distributions ptrauth_utils_auth_blob_generic(const void * ptr, size_t len_bytes, uint64_t data, int flags, ptrauth_generic_signature_t signature)
58*a325d9c4SApple OSS Distributions {
59*a325d9c4SApple OSS Distributions 	ptrauth_generic_signature_t calculated_signature = 0;
60*a325d9c4SApple OSS Distributions 
61*a325d9c4SApple OSS Distributions 	if (ptr == NULL) {
62*a325d9c4SApple OSS Distributions 		if (flags & PTRAUTH_NON_NULL) {
63*a325d9c4SApple OSS Distributions 			panic("ptrauth_utils_auth_blob_generic: ptr must not be NULL");
64*a325d9c4SApple OSS Distributions 		} else {
65*a325d9c4SApple OSS Distributions 			return;
66*a325d9c4SApple OSS Distributions 		}
67*a325d9c4SApple OSS Distributions 	}
68*a325d9c4SApple OSS Distributions 
69*a325d9c4SApple OSS Distributions 	if ((calculated_signature = ptrauth_utils_sign_blob_generic(ptr, len_bytes, data, flags)) == signature) {
70*a325d9c4SApple OSS Distributions 		return;
71*a325d9c4SApple OSS Distributions 	} else {
72*a325d9c4SApple OSS Distributions 		panic("signature mismatch for %lu bytes at %p, calculated %lx vs %lx", len_bytes,
73*a325d9c4SApple OSS Distributions 		    ptr,
74*a325d9c4SApple OSS Distributions 		    calculated_signature,
75*a325d9c4SApple OSS Distributions 		    signature);
76*a325d9c4SApple OSS Distributions 	}
77*a325d9c4SApple OSS Distributions }
78*a325d9c4SApple OSS Distributions #else
79*a325d9c4SApple OSS Distributions void
ptrauth_utils_auth_blob_generic(__unused const void * ptr,__unused size_t len_bytes,__unused uint64_t data,__unused int flags,__unused ptrauth_generic_signature_t signature)80*a325d9c4SApple OSS Distributions ptrauth_utils_auth_blob_generic(__unused const void * ptr, __unused size_t len_bytes, __unused uint64_t data, __unused int flags, __unused ptrauth_generic_signature_t signature)
81*a325d9c4SApple OSS Distributions {
82*a325d9c4SApple OSS Distributions 	return;
83*a325d9c4SApple OSS Distributions }
84*a325d9c4SApple OSS Distributions #endif // __has_feature(ptrauth_calls)
85