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kern_exec.c
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kern_exec.c
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/*
* Copyright (c) 2000-2020 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_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. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* 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_OSREFERENCE_LICENSE_HEADER_END@
*/
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
* Mach Operating System
* Copyright (c) 1987 Carnegie-Mellon University
* All rights reserved. The CMU software License Agreement specifies
* the terms and conditions for use and redistribution.
*/
/*-
* Copyright (c) 1982, 1986, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)kern_exec.c 8.1 (Berkeley) 6/10/93
*/
/*
* NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
* support for mandatory and extensible security protections. This notice
* is included in support of clause 2.2 (b) of the Apple Public License,
* Version 2.0.
*/
#include <machine/reg.h>
#include <machine/cpu_capabilities.h>
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/proc_internal.h>
#include <sys/kauth.h>
#include <sys/user.h>
#include <sys/socketvar.h>
#include <sys/malloc.h>
#include <sys/namei.h>
#include <sys/mount_internal.h>
#include <sys/vnode_internal.h>
#include <sys/file_internal.h>
#include <sys/stat.h>
#include <sys/uio_internal.h>
#include <sys/acct.h>
#include <sys/exec.h>
#include <sys/kdebug.h>
#include <sys/signal.h>
#include <sys/aio_kern.h>
#include <sys/sysproto.h>
#include <sys/sysctl.h>
#include <sys/persona.h>
#include <sys/reason.h>
#if SYSV_SHM
#include <sys/shm_internal.h> /* shmexec() */
#endif
#include <sys/ubc_internal.h> /* ubc_map() */
#include <sys/spawn.h>
#include <sys/spawn_internal.h>
#include <sys/process_policy.h>
#include <sys/codesign.h>
#include <sys/random.h>
#include <crypto/sha1.h>
#include <libkern/libkern.h>
#include <libkern/crypto/sha2.h>
#include <security/audit/audit.h>
#include <ipc/ipc_types.h>
#include <mach/mach_param.h>
#include <mach/mach_types.h>
#include <mach/port.h>
#include <mach/task.h>
#include <mach/task_access.h>
#include <mach/thread_act.h>
#include <mach/vm_map.h>
#include <mach/mach_vm.h>
#include <mach/vm_param.h>
#include <kern/sched_prim.h> /* thread_wakeup() */
#include <kern/affinity.h>
#include <kern/assert.h>
#include <kern/task.h>
#include <kern/coalition.h>
#include <kern/policy_internal.h>
#include <kern/kalloc.h>
#include <kern/zalloc.h> /* zone_userspace_reboot_checks() */
#include <os/log.h>
#if CONFIG_MACF
#include <security/mac_framework.h>
#include <security/mac_mach_internal.h>
#endif
#if CONFIG_AUDIT
#include <bsm/audit_kevents.h>
#endif
#if CONFIG_ARCADE
#include <kern/arcade.h>
#endif
#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <vm/vm_protos.h>
#include <vm/vm_kern.h>
#include <vm/vm_fault.h>
#include <vm/vm_pageout.h>
#include <vm/pmap.h>
#include <kdp/kdp_dyld.h>
#include <machine/machine_routines.h>
#include <machine/pal_routines.h>
#include <pexpert/pexpert.h>
#if CONFIG_MEMORYSTATUS
#include <sys/kern_memorystatus.h>
#endif
#include <IOKit/IOBSD.h>
#include <IOKit/IOPlatformExpert.h>
#include "kern_exec_internal.h"
extern boolean_t vm_darkwake_mode;
/* enable crash reports on various exec failures */
static TUNABLE(bool, bootarg_execfailurereports, "execfailurecrashes", false);
#if XNU_TARGET_OS_OSX
#if __has_feature(ptrauth_calls)
static TUNABLE(bool, bootarg_arm64e_preview_abi, "-arm64e_preview_abi", false);
#endif /* __has_feature(ptrauth_calls) */
#if DEBUG || DEVELOPMENT
static TUNABLE(bool, unentitled_ios_sim_launch, "unentitled_ios_sim_launch", false);
#endif /* DEBUG || DEVELOPMENT */
#endif /* XNU_TARGET_OS_OSX */
#if CONFIG_DTRACE
/* Do not include dtrace.h, it redefines kmem_[alloc/free] */
extern void dtrace_proc_exec(proc_t);
extern void (*dtrace_proc_waitfor_exec_ptr)(proc_t);
/*
* Since dtrace_proc_waitfor_exec_ptr can be added/removed in dtrace_subr.c,
* we will store its value before actually calling it.
*/
static void (*dtrace_proc_waitfor_hook)(proc_t) = NULL;
#include <sys/dtrace_ptss.h>
#endif
#if __has_feature(ptrauth_calls)
static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_per_team_id,
"vm_shared_region_per_team_id", 1);
static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_by_entitlement,
"vm_shared_region_by_entitlement", 1);
/* Upon userland request, reslide the shared cache. */
static TUNABLE_DEV_WRITEABLE(int, vm_shared_region_reslide_aslr,
"vm_shared_region_reslide_aslr",
#if CONFIG_RESLIDE_SHARED_CACHE
1
#else
0
#endif /* CONFIG_RESLIDE_SHARED_CACHE */
);
/*
* Flag to control what processes should get shared cache randomize resliding
* after a fault in the shared cache region:
*
* 0 - all processes get a new randomized slide
* 1 - only platform processes get a new randomized slide
*/
TUNABLE_DEV_WRITEABLE(int, vm_shared_region_reslide_restrict,
"vm_shared_region_reslide_restrict", 1);
#if DEVELOPMENT || DEBUG
SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_per_team_id,
CTLFLAG_RW, &vm_shared_region_per_team_id, 0, "");
SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_by_entitlement,
CTLFLAG_RW, &vm_shared_region_by_entitlement, 0, "");
SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_reslide_restrict,
CTLFLAG_RW, &vm_shared_region_reslide_restrict, 0, "");
SYSCTL_INT(_vm, OID_AUTO, vm_shared_region_reslide_aslr,
CTLFLAG_RW, &vm_shared_region_reslide_aslr, 0, "");
#endif
#endif /* __has_feature(ptrauth_calls) */
/*
* Enable DriverKit shared region. This is disabled by default, and kernelmanagerd/driverkitd will set this to 1 if it
* detects the presence of a DriverKit shared cache.
*/
int vm_enable_driverkit_shared_region = 0;
thread_t fork_create_child(task_t parent_task,
coalition_t *parent_coalition,
proc_t child_proc,
int inherit_memory,
int is_64bit_addr,
int is_64bit_data,
int in_exec);
extern void proc_apply_task_networkbg_internal(proc_t, thread_t);
extern void task_set_did_exec_flag(task_t task);
extern void task_clear_exec_copy_flag(task_t task);
proc_t proc_exec_switch_task(proc_t p, task_t old_task, task_t new_task, thread_t new_thread, void **inherit);
boolean_t task_is_active(task_t);
boolean_t thread_is_active(thread_t thread);
void thread_copy_resource_info(thread_t dst_thread, thread_t src_thread);
void *ipc_importance_exec_switch_task(task_t old_task, task_t new_task);
extern void ipc_importance_release(void *elem);
extern boolean_t task_has_watchports(task_t task);
extern void task_set_no_smt(task_t task);
#if defined(HAS_APPLE_PAC)
char *task_get_vm_shared_region_id_and_jop_pid(task_t task, uint64_t *jop_pid);
#endif
task_t convert_port_to_task(ipc_port_t port);
/*
* Mach things for which prototypes are unavailable from Mach headers
*/
#define IPC_OBJECT_COPYIN_FLAGS_ALLOW_IMMOVABLE_SEND 0x1
void ipc_task_reset(
task_t task);
void ipc_thread_reset(
thread_t thread);
kern_return_t ipc_object_copyin(
ipc_space_t space,
mach_port_name_t name,
mach_msg_type_name_t msgt_name,
ipc_object_t *objectp,
mach_port_context_t context,
mach_msg_guard_flags_t *guard_flags,
uint32_t kmsg_flags);
void ipc_port_release_send(ipc_port_t);
#if DEVELOPMENT || DEBUG
void task_importance_update_owner_info(task_t);
#endif
extern struct savearea *get_user_regs(thread_t);
__attribute__((noinline)) int __EXEC_WAITING_ON_TASKGATED_CODE_SIGNATURE_UPCALL__(mach_port_t task_access_port, int32_t new_pid);
#include <kern/thread.h>
#include <kern/task.h>
#include <kern/ast.h>
#include <kern/mach_loader.h>
#include <kern/mach_fat.h>
#include <mach-o/fat.h>
#include <mach-o/loader.h>
#include <machine/vmparam.h>
#include <sys/imgact.h>
#include <sys/sdt.h>
/*
* EAI_ITERLIMIT The maximum number of times to iterate an image
* activator in exec_activate_image() before treating
* it as malformed/corrupt.
*/
#define EAI_ITERLIMIT 3
/*
* For #! interpreter parsing
*/
#define IS_WHITESPACE(ch) ((ch == ' ') || (ch == '\t'))
#define IS_EOL(ch) ((ch == '#') || (ch == '\n'))
extern vm_map_t bsd_pageable_map;
extern const struct fileops vnops;
extern int nextpidversion;
#define USER_ADDR_ALIGN(addr, val) \
( ( (user_addr_t)(addr) + (val) - 1) \
& ~((val) - 1) )
/*
* For subsystem root support
*/
#define SPAWN_SUBSYSTEM_ROOT_ENTITLEMENT "com.apple.private.spawn-subsystem-root"
/* Platform Code Exec Logging */
static int platform_exec_logging = 0;
SYSCTL_DECL(_security_mac);
SYSCTL_INT(_security_mac, OID_AUTO, platform_exec_logging, CTLFLAG_RW, &platform_exec_logging, 0,
"log cdhashes for all platform binary executions");
static os_log_t peLog = OS_LOG_DEFAULT;
struct exec_port_actions {
uint32_t portwatch_count;
uint32_t registered_count;
ipc_port_t *portwatch_array;
ipc_port_t *registered_array;
};
struct image_params; /* Forward */
static int exec_activate_image(struct image_params *imgp);
static int exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp);
static int load_return_to_errno(load_return_t lrtn);
static int execargs_alloc(struct image_params *imgp);
static int execargs_free(struct image_params *imgp);
static int exec_check_permissions(struct image_params *imgp);
static int exec_extract_strings(struct image_params *imgp);
static int exec_add_apple_strings(struct image_params *imgp, const load_result_t *load_result);
static int exec_handle_sugid(struct image_params *imgp);
static int sugid_scripts = 0;
SYSCTL_INT(_kern, OID_AUTO, sugid_scripts, CTLFLAG_RW | CTLFLAG_LOCKED, &sugid_scripts, 0, "");
static kern_return_t create_unix_stack(vm_map_t map, load_result_t* load_result, proc_t p);
static int copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size);
static void exec_resettextvp(proc_t, struct image_params *);
static int check_for_signature(proc_t, struct image_params *);
static void exec_prefault_data(proc_t, struct image_params *, load_result_t *);
static errno_t exec_handle_port_actions(struct image_params *imgp,
struct exec_port_actions *port_actions);
static errno_t exec_handle_spawnattr_policy(proc_t p, thread_t thread, int psa_apptype, uint64_t psa_qos_clamp,
task_role_t psa_darwin_role, struct exec_port_actions *port_actions);
static void exec_port_actions_destroy(struct exec_port_actions *port_actions);
/*
* exec_add_user_string
*
* Add the requested string to the string space area.
*
* Parameters; struct image_params * image parameter block
* user_addr_t string to add to strings area
* int segment from which string comes
* boolean_t TRUE if string contributes to NCARGS
*
* Returns: 0 Success
* !0 Failure errno from copyinstr()
*
* Implicit returns:
* (imgp->ip_strendp) updated location of next add, if any
* (imgp->ip_strspace) updated byte count of space remaining
* (imgp->ip_argspace) updated byte count of space in NCARGS
*/
__attribute__((noinline))
static int
exec_add_user_string(struct image_params *imgp, user_addr_t str, int seg, boolean_t is_ncargs)
{
int error = 0;
do {
size_t len = 0;
int space;
if (is_ncargs) {
space = imgp->ip_argspace; /* by definition smaller than ip_strspace */
} else {
space = imgp->ip_strspace;
}
if (space <= 0) {
error = E2BIG;
break;
}
if (!UIO_SEG_IS_USER_SPACE(seg)) {
char *kstr = CAST_DOWN(char *, str); /* SAFE */
error = copystr(kstr, imgp->ip_strendp, space, &len);
} else {
error = copyinstr(str, imgp->ip_strendp, space, &len);
}
imgp->ip_strendp += len;
imgp->ip_strspace -= len;
if (is_ncargs) {
imgp->ip_argspace -= len;
}
} while (error == ENAMETOOLONG);
return error;
}
/*
* dyld is now passed the executable path as a getenv-like variable
* in the same fashion as the stack_guard and malloc_entropy keys.
*/
#define EXECUTABLE_KEY "executable_path="
/*
* exec_save_path
*
* To support new app package launching for Mac OS X, the dyld needs the
* first argument to execve() stored on the user stack.
*
* Save the executable path name at the bottom of the strings area and set
* the argument vector pointer to the location following that to indicate
* the start of the argument and environment tuples, setting the remaining
* string space count to the size of the string area minus the path length.
*
* Parameters; struct image_params * image parameter block
* char * path used to invoke program
* int segment from which path comes
*
* Returns: int 0 Success
* EFAULT Bad address
* copy[in]str:EFAULT Bad address
* copy[in]str:ENAMETOOLONG Filename too long
*
* Implicit returns:
* (imgp->ip_strings) saved path
* (imgp->ip_strspace) space remaining in ip_strings
* (imgp->ip_strendp) start of remaining copy area
* (imgp->ip_argspace) space remaining of NCARGS
* (imgp->ip_applec) Initial applev[0]
*
* Note: We have to do this before the initial namei() since in the
* path contains symbolic links, namei() will overwrite the
* original path buffer contents. If the last symbolic link
* resolved was a relative pathname, we would lose the original
* "path", which could be an absolute pathname. This might be
* unacceptable for dyld.
*/
static int
exec_save_path(struct image_params *imgp, user_addr_t path, int seg, const char **excpath)
{
int error;
size_t len;
char *kpath;
// imgp->ip_strings can come out of a cache, so we need to obliterate the
// old path.
memset(imgp->ip_strings, '\0', strlen(EXECUTABLE_KEY) + MAXPATHLEN);
len = MIN(MAXPATHLEN, imgp->ip_strspace);
switch (seg) {
case UIO_USERSPACE32:
case UIO_USERSPACE64: /* Same for copyin()... */
error = copyinstr(path, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
break;
case UIO_SYSSPACE:
kpath = CAST_DOWN(char *, path); /* SAFE */
error = copystr(kpath, imgp->ip_strings + strlen(EXECUTABLE_KEY), len, &len);
break;
default:
error = EFAULT;
break;
}
if (!error) {
bcopy(EXECUTABLE_KEY, imgp->ip_strings, strlen(EXECUTABLE_KEY));
len += strlen(EXECUTABLE_KEY);
imgp->ip_strendp += len;
imgp->ip_strspace -= len;
if (excpath) {
*excpath = imgp->ip_strings + strlen(EXECUTABLE_KEY);
}
}
return error;
}
/*
* exec_reset_save_path
*
* If we detect a shell script, we need to reset the string area
* state so that the interpreter can be saved onto the stack.
*
* Parameters; struct image_params * image parameter block
*
* Returns: int 0 Success
*
* Implicit returns:
* (imgp->ip_strings) saved path
* (imgp->ip_strspace) space remaining in ip_strings
* (imgp->ip_strendp) start of remaining copy area
* (imgp->ip_argspace) space remaining of NCARGS
*
*/
static int
exec_reset_save_path(struct image_params *imgp)
{
imgp->ip_strendp = imgp->ip_strings;
imgp->ip_argspace = NCARGS;
imgp->ip_strspace = (NCARGS + PAGE_SIZE);
return 0;
}
/*
* exec_shell_imgact
*
* Image activator for interpreter scripts. If the image begins with
* the characters "#!", then it is an interpreter script. Verify the
* length of the script line indicating the interpreter is not in
* excess of the maximum allowed size. If this is the case, then
* break out the arguments, if any, which are separated by white
* space, and copy them into the argument save area as if they were
* provided on the command line before all other arguments. The line
* ends when we encounter a comment character ('#') or newline.
*
* Parameters; struct image_params * image parameter block
*
* Returns: -1 not an interpreter (keep looking)
* -3 Success: interpreter: relookup
* >0 Failure: interpreter: error number
*
* A return value other than -1 indicates subsequent image activators should
* not be given the opportunity to attempt to activate the image.
*/
static int
exec_shell_imgact(struct image_params *imgp)
{
char *vdata = imgp->ip_vdata;
char *ihp;
char *line_startp, *line_endp;
char *interp;
/*
* Make sure it's a shell script. If we've already redirected
* from an interpreted file once, don't do it again.
*/
if (vdata[0] != '#' ||
vdata[1] != '!' ||
(imgp->ip_flags & IMGPF_INTERPRET) != 0) {
return -1;
}
if (imgp->ip_origcputype != 0) {
/* Fat header previously matched, don't allow shell script inside */
return -1;
}
imgp->ip_flags |= IMGPF_INTERPRET;
imgp->ip_interp_sugid_fd = -1;
imgp->ip_interp_buffer[0] = '\0';
/* Check to see if SUGID scripts are permitted. If they aren't then
* clear the SUGID bits.
* imgp->ip_vattr is known to be valid.
*/
if (sugid_scripts == 0) {
imgp->ip_origvattr->va_mode &= ~(VSUID | VSGID);
}
/* Try to find the first non-whitespace character */
for (ihp = &vdata[2]; ihp < &vdata[IMG_SHSIZE]; ihp++) {
if (IS_EOL(*ihp)) {
/* Did not find interpreter, "#!\n" */
return ENOEXEC;
} else if (IS_WHITESPACE(*ihp)) {
/* Whitespace, like "#! /bin/sh\n", keep going. */
} else {
/* Found start of interpreter */
break;
}
}
if (ihp == &vdata[IMG_SHSIZE]) {
/* All whitespace, like "#! " */
return ENOEXEC;
}
line_startp = ihp;
/* Try to find the end of the interpreter+args string */
for (; ihp < &vdata[IMG_SHSIZE]; ihp++) {
if (IS_EOL(*ihp)) {
/* Got it */
break;
} else {
/* Still part of interpreter or args */
}
}
if (ihp == &vdata[IMG_SHSIZE]) {
/* A long line, like "#! blah blah blah" without end */
return ENOEXEC;
}
/* Backtrack until we find the last non-whitespace */
while (IS_EOL(*ihp) || IS_WHITESPACE(*ihp)) {
ihp--;
}
/* The character after the last non-whitespace is our logical end of line */
line_endp = ihp + 1;
/*
* Now we have pointers to the usable part of:
*
* "#! /usr/bin/int first second third \n"
* ^ line_startp ^ line_endp
*/
/* copy the interpreter name */
interp = imgp->ip_interp_buffer;
for (ihp = line_startp; (ihp < line_endp) && !IS_WHITESPACE(*ihp); ihp++) {
*interp++ = *ihp;
}
*interp = '\0';
exec_reset_save_path(imgp);
exec_save_path(imgp, CAST_USER_ADDR_T(imgp->ip_interp_buffer),
UIO_SYSSPACE, NULL);
/* Copy the entire interpreter + args for later processing into argv[] */
interp = imgp->ip_interp_buffer;
for (ihp = line_startp; (ihp < line_endp); ihp++) {
*interp++ = *ihp;
}
*interp = '\0';
#if CONFIG_SETUID
/*
* If we have an SUID or SGID script, create a file descriptor
* from the vnode and pass /dev/fd/%d instead of the actual
* path name so that the script does not get opened twice
*/
if (imgp->ip_origvattr->va_mode & (VSUID | VSGID)) {
proc_t p;
struct fileproc *fp;
int fd;
int error;
p = vfs_context_proc(imgp->ip_vfs_context);
error = falloc(p, &fp, &fd, imgp->ip_vfs_context);
if (error) {
return error;
}
fp->fp_glob->fg_flag = FREAD;
fp->fp_glob->fg_ops = &vnops;
fp_set_data(fp, imgp->ip_vp);
proc_fdlock(p);
procfdtbl_releasefd(p, fd, NULL);
fp_drop(p, fd, fp, 1);
proc_fdunlock(p);
vnode_ref(imgp->ip_vp);
imgp->ip_interp_sugid_fd = fd;
}
#endif /* CONFIG_SETUID */
return -3;
}
/*
* exec_fat_imgact
*
* Image activator for fat 1.0 binaries. If the binary is fat, then we
* need to select an image from it internally, and make that the image
* we are going to attempt to execute. At present, this consists of
* reloading the first page for the image with a first page from the
* offset location indicated by the fat header.
*
* Parameters; struct image_params * image parameter block
*
* Returns: -1 not a fat binary (keep looking)
* -2 Success: encapsulated binary: reread
* >0 Failure: error number
*
* Important: This image activator is byte order neutral.
*
* Note: A return value other than -1 indicates subsequent image
* activators should not be given the opportunity to attempt
* to activate the image.
*
* If we find an encapsulated binary, we make no assertions
* about its validity; instead, we leave that up to a rescan
* for an activator to claim it, and, if it is claimed by one,
* that activator is responsible for determining validity.
*/
static int
exec_fat_imgact(struct image_params *imgp)
{
proc_t p = vfs_context_proc(imgp->ip_vfs_context);
kauth_cred_t cred = kauth_cred_proc_ref(p);
struct fat_header *fat_header = (struct fat_header *)imgp->ip_vdata;
struct _posix_spawnattr *psa = NULL;
struct fat_arch fat_arch;
int resid, error;
load_return_t lret;
if (imgp->ip_origcputype != 0) {
/* Fat header previously matched, don't allow another fat file inside */
error = -1; /* not claimed */
goto bad;
}
/* Make sure it's a fat binary */
if (OSSwapBigToHostInt32(fat_header->magic) != FAT_MAGIC) {
error = -1; /* not claimed */
goto bad;
}
/* imgp->ip_vdata has PAGE_SIZE, zerofilled if the file is smaller */
lret = fatfile_validate_fatarches((vm_offset_t)fat_header, PAGE_SIZE,
(off_t)imgp->ip_vattr->va_data_size);
if (lret != LOAD_SUCCESS) {
error = load_return_to_errno(lret);
goto bad;
}
/* If posix_spawn binprefs exist, respect those prefs. */
psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
if (psa != NULL && psa->psa_binprefs[0] != 0) {
uint32_t pr = 0;
/* Check each preference listed against all arches in header */
for (pr = 0; pr < NBINPREFS; pr++) {
cpu_type_t pref = psa->psa_binprefs[pr];
cpu_type_t subpref = psa->psa_subcpuprefs[pr];
if (pref == 0) {
/* No suitable arch in the pref list */
error = EBADARCH;
goto bad;
}
if (pref == CPU_TYPE_ANY) {
/* Fall through to regular grading */
goto regular_grading;
}
lret = fatfile_getbestarch_for_cputype(pref,
subpref,
(vm_offset_t)fat_header,
PAGE_SIZE,
imgp,
&fat_arch);
if (lret == LOAD_SUCCESS) {
goto use_arch;
}
}
/* Requested binary preference was not honored */
error = EBADEXEC;
goto bad;
}
regular_grading:
/* Look up our preferred architecture in the fat file. */
lret = fatfile_getbestarch((vm_offset_t)fat_header,
PAGE_SIZE,
imgp,
&fat_arch,
(p->p_flag & P_AFFINITY) != 0);
if (lret != LOAD_SUCCESS) {
error = load_return_to_errno(lret);
goto bad;
}
use_arch:
/* Read the Mach-O header out of fat_arch */
error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata,
PAGE_SIZE, fat_arch.offset,
UIO_SYSSPACE, (IO_UNIT | IO_NODELOCKED),
cred, &resid, p);
if (error) {
goto bad;
}
if (resid) {
memset(imgp->ip_vdata + (PAGE_SIZE - resid), 0x0, resid);
}
/* Success. Indicate we have identified an encapsulated binary */
error = -2;
imgp->ip_arch_offset = (user_size_t)fat_arch.offset;
imgp->ip_arch_size = (user_size_t)fat_arch.size;
imgp->ip_origcputype = fat_arch.cputype;
imgp->ip_origcpusubtype = fat_arch.cpusubtype;
bad:
kauth_cred_unref(&cred);
return error;
}
static int
activate_exec_state(task_t task, proc_t p, thread_t thread, load_result_t *result)
{
int ret;
task_set_dyld_info(task, MACH_VM_MIN_ADDRESS, 0);
task_set_64bit(task, result->is_64bit_addr, result->is_64bit_data);
if (result->is_64bit_addr) {
OSBitOrAtomic(P_LP64, &p->p_flag);
get_bsdthread_info(thread)->uu_flag |= UT_LP64;
} else {
OSBitAndAtomic(~((uint32_t)P_LP64), &p->p_flag);
get_bsdthread_info(thread)->uu_flag &= ~UT_LP64;
}
task_set_mach_header_address(task, result->mach_header);
ret = thread_state_initialize(thread);
if (ret != KERN_SUCCESS) {
return ret;
}
if (result->threadstate) {
uint32_t *ts = result->threadstate;
uint32_t total_size = (uint32_t)result->threadstate_sz;
while (total_size > 0) {
uint32_t flavor = *ts++;
uint32_t size = *ts++;
ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size);
if (ret) {
return ret;
}
ts += size;
total_size -= (size + 2) * sizeof(uint32_t);
}
}
thread_setentrypoint(thread, result->entry_point);
return KERN_SUCCESS;
}
void
set_proc_name(struct image_params *imgp, proc_t p)
{
int p_name_len = sizeof(p->p_name) - 1;
if (imgp->ip_ndp->ni_cnd.cn_namelen > p_name_len) {
imgp->ip_ndp->ni_cnd.cn_namelen = p_name_len;
}
bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_name,
(unsigned)imgp->ip_ndp->ni_cnd.cn_namelen);
p->p_name[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0';
if (imgp->ip_ndp->ni_cnd.cn_namelen > MAXCOMLEN) {
imgp->ip_ndp->ni_cnd.cn_namelen = MAXCOMLEN;
}
bcopy((caddr_t)imgp->ip_ndp->ni_cnd.cn_nameptr, (caddr_t)p->p_comm,
(unsigned)imgp->ip_ndp->ni_cnd.cn_namelen);
p->p_comm[imgp->ip_ndp->ni_cnd.cn_namelen] = '\0';
}
#if __has_feature(ptrauth_calls)
/**
* Returns a team ID string that may be used to assign a shared region.
*
* Platform binaries do not have team IDs and will return NULL. Non-platform
* binaries without a team ID will be assigned an artificial team ID of ""
* (empty string) so that they will not be assigned to the default shared
* region.
*
* @param imgp image parameter block
* @return NULL if this is a platform binary, or an appropriate team ID string
* otherwise
*/
static inline const char *
get_teamid_for_shared_region(struct image_params *imgp)
{
assert(imgp->ip_vp != NULL);
const char *ret = csvnode_get_teamid(imgp->ip_vp, imgp->ip_arch_offset);
if (ret) {
return ret;
}
struct cs_blob *blob = csvnode_get_blob(imgp->ip_vp, imgp->ip_arch_offset);
if (csblob_get_platform_binary(blob)) {
return NULL;
} else {
static const char *NO_TEAM_ID = "";
return NO_TEAM_ID;
}
}
/**
* Determines whether ptrauth should be enabled for the provided arm64 CPU subtype.
*
* @param cpusubtype Mach-O style CPU subtype
* @return whether the CPU subtype matches arm64e with the current ptrauth ABI
*/
static inline bool
arm64_cpusubtype_uses_ptrauth(cpu_subtype_t cpusubtype)
{
return (cpusubtype & ~CPU_SUBTYPE_MASK) == CPU_SUBTYPE_ARM64E &&
CPU_SUBTYPE_ARM64_PTR_AUTH_VERSION(cpusubtype) == CPU_SUBTYPE_ARM64_PTR_AUTH_CURRENT_VERSION;
}
#endif /* __has_feature(ptrauth_calls) */
/**
* Returns whether a type/subtype slice matches the requested
* type/subtype.
*
* @param mask Bits to mask from the requested/tested cpu type
* @param req_cpu Requested cpu type
* @param req_subcpu Requested cpu subtype
* @param test_cpu Tested slice cpu type
* @param test_subcpu Tested slice cpu subtype
*/
boolean_t
binary_match(cpu_type_t mask, cpu_type_t req_cpu,
cpu_subtype_t req_subcpu, cpu_type_t test_cpu,
cpu_subtype_t test_subcpu)
{
if ((test_cpu & ~mask) != (req_cpu & ~mask)) {
return FALSE;
}
test_subcpu &= ~CPU_SUBTYPE_MASK;
req_subcpu &= ~CPU_SUBTYPE_MASK;
if (test_subcpu != req_subcpu && req_subcpu != (CPU_SUBTYPE_ANY & ~CPU_SUBTYPE_MASK)) {
return FALSE;
}
return TRUE;
}
/*
* exec_mach_imgact
*
* Image activator for mach-o 1.0 binaries.
*
* Parameters; struct image_params * image parameter block
*
* Returns: -1 not a fat binary (keep looking)
* -2 Success: encapsulated binary: reread
* >0 Failure: error number
* EBADARCH Mach-o binary, but with an unrecognized
* architecture
* ENOMEM No memory for child process after -
* can only happen after vfork()