#include <cputypes.h>
#include <machine/reg.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>
#if SYSV_SHM
#include <sys/shm_internal.h>
#endif
#include <sys/ubc_internal.h>
#include <sys/spawn.h>
#include <sys/spawn_internal.h>
#include <sys/codesign.h>
#include <crypto/sha1.h>
#include <security/audit/audit.h>
#include <ipc/ipc_types.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>
#include <kern/affinity.h>
#include <kern/assert.h>
#if CONFIG_MACF
#include <security/mac.h>
#include <security/mac_mach_internal.h>
#endif
#include <vm/vm_map.h>
#include <vm/vm_kern.h>
#include <vm/vm_protos.h>
#include <vm/vm_kern.h>
#if CONFIG_DTRACE
extern void (*dtrace_fasttrap_exec_ptr)(proc_t);
extern void (*dtrace_helpers_cleanup)(proc_t);
extern void dtrace_lazy_dofs_destroy(proc_t);
#include <sys/dtrace_ptss.h>
#endif
thread_t fork_create_child(task_t parent_task, proc_t child_proc, int inherit_memory, int is64bit);
void vfork_exit(proc_t p, int rv);
int setsigvec(proc_t, thread_t, int, struct __kern_sigaction *, boolean_t in_sigstart);
void workqueue_exit(struct proc *);
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);
void ipc_port_release_send(ipc_port_t);
extern struct savearea *get_user_regs(thread_t);
#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>
#define SIZE_MAXPTR 8
#define SIZE_IMG_STRSPACE (NCARGS - 2 * SIZE_MAXPTR)
#define EAI_ITERLIMIT 10
extern vm_map_t bsd_pageable_map;
extern struct fileops vnops;
#define ROUND_PTR(type, addr) \
(type *)( ( (uintptr_t)(addr) + 16 - 1) \
& ~(16 - 1) )
struct image_params;
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_handle_sugid(struct image_params *imgp);
static int sugid_scripts = 0;
SYSCTL_INT (_kern, OID_AUTO, sugid_scripts, CTLFLAG_RW, &sugid_scripts, 0, "");
static kern_return_t create_unix_stack(vm_map_t map, user_addr_t user_stack,
int customstack, 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 *);
__private_extern__
int open1(vfs_context_t, struct nameidata *, int, struct vnode_attr *, int32_t *);
static int
exec_add_string(struct image_params *imgp, user_addr_t str)
{
int error = 0;
do {
size_t len = 0;
if (imgp->ip_strspace <= 0) {
error = E2BIG;
break;
}
if (!UIO_SEG_IS_USER_SPACE(imgp->ip_seg)) {
char *kstr = CAST_DOWN(char *,str);
error = copystr(kstr, imgp->ip_strendp, imgp->ip_strspace, &len);
} else {
error = copyinstr(str, imgp->ip_strendp, imgp->ip_strspace,
&len);
}
imgp->ip_strendp += len;
imgp->ip_strspace -= len;
} while (error == ENAMETOOLONG);
return error;
}
static int
exec_save_path(struct image_params *imgp, user_addr_t path, int seg)
{
int error;
size_t len;
char *kpath = CAST_DOWN(char *,path);
imgp->ip_strendp = imgp->ip_strings;
imgp->ip_strspace = SIZE_IMG_STRSPACE;
len = MIN(MAXPATHLEN, imgp->ip_strspace);
switch(seg) {
case UIO_USERSPACE32:
case UIO_USERSPACE64:
error = copyinstr(path, imgp->ip_strings, len, &len);
break;
case UIO_SYSSPACE:
error = copystr(kpath, imgp->ip_strings, len, &len);
break;
default:
error = EFAULT;
break;
}
if (!error) {
imgp->ip_strendp += len;
imgp->ip_strspace -= len;
imgp->ip_argv = imgp->ip_strendp;
}
return(error);
}
#ifdef IMGPF_POWERPC
static int
exec_powerpc32_imgact(struct image_params *imgp)
{
struct mach_header *mach_header = (struct mach_header *)imgp->ip_vdata;
int error;
size_t len = 0;
if (mach_header->magic != MH_CIGAM) {
if (mach_header->magic == MH_CIGAM_64)
return (EBADARCH);
return (-1);
}
if (exec_archhandler_ppc.path[0] == 0)
return (EBADARCH);
if (!imgp->ip_origcputype) {
imgp->ip_origcputype =
OSSwapBigToHostInt32(mach_header->cputype);
imgp->ip_origcpusubtype =
OSSwapBigToHostInt32(mach_header->cpusubtype);
}
imgp->ip_flags |= IMGPF_POWERPC;
error = copystr(exec_archhandler_ppc.path, imgp->ip_interp_name,
IMG_SHSIZE, &len);
if (error)
return (error);
strlcpy(imgp->ip_p_comm, imgp->ip_ndp->ni_cnd.cn_nameptr, MAXCOMLEN+1);
return (-3);
}
#endif
static int
exec_shell_imgact(struct image_params *imgp)
{
char *vdata = imgp->ip_vdata;
char *ihp;
char *line_endp;
char *interp;
char temp[16];
proc_t p;
struct fileproc *fp;
int fd;
int error;
size_t len;
if (vdata[0] != '#' ||
vdata[1] != '!' ||
(imgp->ip_flags & IMGPF_INTERPRET) != 0) {
return (-1);
}
#ifdef IMGPF_POWERPC
if ((imgp->ip_flags & IMGPF_POWERPC) != 0)
return (EBADARCH);
#endif
imgp->ip_flags |= IMGPF_INTERPRET;
if (sugid_scripts == 0) {
imgp->ip_origvattr->va_mode &= ~(VSUID | VSGID);
}
for( ihp = &vdata[2]; *ihp != '\n' && *ihp != '#'; ihp++) {
if (ihp >= &vdata[IMG_SHSIZE])
return (ENOEXEC);
}
line_endp = ihp;
ihp = &vdata[2];
while ( ihp < line_endp && ((*ihp == ' ') || (*ihp == '\t')))
ihp++;
for (;line_endp > ihp && ((*line_endp == ' ') || (*line_endp == '\t')); line_endp--)
continue;
if (line_endp == ihp)
return (ENOEXEC);
interp = imgp->ip_interp_name;
while ((ihp < line_endp) && (*ihp != ' ') && (*ihp != '\t'))
*interp++ = *ihp++;
*interp = '\0';
exec_save_path(imgp, CAST_USER_ADDR_T(imgp->ip_interp_name),
UIO_SYSSPACE);
ihp = &vdata[2];
while (ihp < line_endp) {
while ((*ihp == ' ') || (*ihp == '\t'))
ihp++;
if (ihp >= line_endp)
break;
while ((ihp < line_endp) && (*ihp != ' ') && (*ihp != '\t')) {
*imgp->ip_strendp++ = *ihp++;
imgp->ip_strspace--;
}
*imgp->ip_strendp++ = 0;
imgp->ip_strspace--;
imgp->ip_argc++;
}
if (imgp->ip_origvattr->va_mode & (VSUID | VSGID)) {
p = vfs_context_proc(imgp->ip_vfs_context);
error = falloc(p, &fp, &fd, imgp->ip_vfs_context);
if (error)
return(error);
fp->f_fglob->fg_flag = FREAD;
fp->f_fglob->fg_type = DTYPE_VNODE;
fp->f_fglob->fg_ops = &vnops;
fp->f_fglob->fg_data = (caddr_t)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);
snprintf(temp, sizeof(temp), "/dev/fd/%d", fd);
error = copyoutstr(temp, imgp->ip_user_fname, sizeof(temp), &len);
if (error)
return(error);
}
return (-3);
}
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 ((fat_header->magic != FAT_MAGIC) &&
(fat_header->magic != FAT_CIGAM)) {
error = -1;
goto bad;
}
psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
if (psa != NULL && psa->psa_binprefs[0] != 0) {
struct fat_arch *arches = (struct fat_arch *) (fat_header + 1);
int nfat_arch = 0, pr = 0, f = 0;
nfat_arch = OSSwapBigToHostInt32(fat_header->nfat_arch);
for (pr = 0; pr < NBINPREFS; pr++) {
cpu_type_t pref = psa->psa_binprefs[pr];
if (pref == 0) {
error = EBADARCH;
goto bad;
}
if (pref == CPU_TYPE_ANY) {
break;
}
for (f = 0; f < nfat_arch; f++) {
cpu_type_t archtype = OSSwapBigToHostInt32(
arches[f].cputype);
cpu_type_t archsubtype = OSSwapBigToHostInt32(
arches[f].cpusubtype) & ~CPU_SUBTYPE_MASK;
if (pref == archtype &&
grade_binary(archtype, archsubtype)) {
fat_arch.cputype = archtype;
fat_arch.cpusubtype = archsubtype;
fat_arch.offset = OSSwapBigToHostInt32(
arches[f].offset);
fat_arch.size = OSSwapBigToHostInt32(
arches[f].size);
fat_arch.align = OSSwapBigToHostInt32(
arches[f].align);
goto use_arch;
}
}
}
}
lret = fatfile_getarch_affinity(imgp->ip_vp,
(vm_offset_t)fat_header,
&fat_arch,
(p->p_flag & P_AFFINITY));
if (lret != LOAD_SUCCESS) {
error = load_return_to_errno(lret);
goto bad;
}
use_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) {
error = EBADEXEC;
goto bad;
}
error = -2;
imgp->ip_arch_offset = (user_size_t)fat_arch.offset;
imgp->ip_arch_size = (user_size_t)fat_arch.size;
bad:
kauth_cred_unref(&cred);
return (error);
}
static int
exec_mach_imgact(struct image_params *imgp)
{
struct mach_header *mach_header = (struct mach_header *)imgp->ip_vdata;
proc_t p = vfs_context_proc(imgp->ip_vfs_context);
int error = 0;
int vfexec = 0;
task_t task;
task_t new_task = NULL;
thread_t thread;
struct uthread *uthread;
vm_map_t old_map = VM_MAP_NULL;
vm_map_t map;
load_return_t lret;
load_result_t load_result;
struct _posix_spawnattr *psa = NULL;
int spawn = (imgp->ip_flags & IMGPF_SPAWN);
if ((mach_header->magic != MH_MAGIC) &&
(mach_header->magic != MH_MAGIC_64)) {
error = -1;
goto bad;
}
switch (mach_header->filetype) {
case MH_DYLIB:
case MH_BUNDLE:
error = -1;
goto bad;
}
if (!imgp->ip_origcputype) {
imgp->ip_origcputype = mach_header->cputype;
imgp->ip_origcpusubtype = mach_header->cpusubtype;
}
task = current_task();
thread = current_thread();
uthread = get_bsdthread_info(thread);
if (uthread->uu_flag & UT_VFORK)
vfexec = 1;
if ((mach_header->cputype & CPU_ARCH_ABI64) == CPU_ARCH_ABI64)
imgp->ip_flags |= IMGPF_IS_64BIT;
psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
if (psa != NULL && psa->psa_binprefs[0] != 0) {
int pr = 0;
for (pr = 0; pr < NBINPREFS; pr++) {
cpu_type_t pref = psa->psa_binprefs[pr];
if (pref == 0) {
error = EBADARCH;
goto bad;
}
if (pref == CPU_TYPE_ANY) {
goto grade;
}
if (pref == imgp->ip_origcputype) {
goto grade;
}
}
error = EBADARCH;
goto bad;
}
grade:
if (!grade_binary(imgp->ip_origcputype & ~CPU_SUBTYPE_LIB64,
imgp->ip_origcpusubtype & ~CPU_SUBTYPE_MASK)) {
error = EBADARCH;
goto bad;
}
error = exec_extract_strings(imgp);
if (error)
goto bad;
AUDIT_ARG(argv, imgp->ip_argv, imgp->ip_argc,
imgp->ip_strendargvp - imgp->ip_argv);
AUDIT_ARG(envv, imgp->ip_strendargvp, imgp->ip_envc,
imgp->ip_strendp - imgp->ip_strendargvp);
imgp->ip_strendp[0] = 0;
imgp->ip_strendp[1] = 0;
imgp->ip_strendp[2] = 0;
imgp->ip_strendp += (((imgp->ip_strendp - imgp->ip_strings) + NBPW-1) & ~(NBPW-1));
#ifdef IMGPF_POWERPC
if (imgp->ip_vattr->va_fsid == exec_archhandler_ppc.fsid &&
imgp->ip_vattr->va_fileid == (uint64_t)((u_long)exec_archhandler_ppc.fileid)) {
imgp->ip_flags |= IMGPF_POWERPC;
}
#endif
if (vfexec || spawn) {
if (vfexec) {
imgp->ip_new_thread = fork_create_child(task, p, FALSE, (imgp->ip_flags & IMGPF_IS_64BIT));
if (imgp->ip_new_thread == NULL) {
error = ENOMEM;
goto bad;
}
}
thread = imgp->ip_new_thread;
uthread = get_bsdthread_info(thread);
task = new_task = get_threadtask(thread);
map = get_task_map(task);
} else {
map = VM_MAP_NULL;
}
task_set_dyld_info(task, MACH_VM_MIN_ADDRESS, 0);
if (imgp->ip_flags & IMGPF_IS_64BIT) {
task_set_64bit(task, TRUE);
OSBitOrAtomic(P_LP64, &p->p_flag);
} else {
task_set_64bit(task, FALSE);
OSBitAndAtomic(~((uint32_t)P_LP64), &p->p_flag);
}
lret = load_machfile(imgp, mach_header, thread, map, &load_result);
if (lret != LOAD_SUCCESS) {
error = load_return_to_errno(lret);
goto badtoolate;
}
vm_map_set_user_wire_limit(get_task_map(task), p->p_rlimit[RLIMIT_MEMLOCK].rlim_cur);
if (load_result.csflags & CS_VALID) {
imgp->ip_csflags |= load_result.csflags &
(CS_VALID|
CS_HARD|CS_KILL|CS_EXEC_SET_HARD|CS_EXEC_SET_KILL);
} else {
imgp->ip_csflags &= ~CS_VALID;
}
if (p->p_csflags & CS_EXEC_SET_HARD)
imgp->ip_csflags |= CS_HARD;
if (p->p_csflags & CS_EXEC_SET_KILL)
imgp->ip_csflags |= CS_KILL;
vm_map_exec(get_task_map(task),
task,
(void *) p->p_fd->fd_rdir,
#ifdef IMGPF_POWERPC
imgp->ip_flags & IMGPF_POWERPC ?
CPU_TYPE_POWERPC :
#endif
cpu_type());
fdexec(p);
error = exec_handle_sugid(imgp);
if (!vfexec && !spawn && (p->p_lflag & P_LTRACED))
psignal(p, SIGTRAP);
if (error) {
goto badtoolate;
}
if (load_result.unixproc &&
create_unix_stack(get_task_map(task),
load_result.user_stack,
load_result.customstack,
p) != KERN_SUCCESS) {
error = load_return_to_errno(LOAD_NOSPACE);
goto badtoolate;
}
if (vfexec == 0 && spawn == 0) {
(void)workqueue_exit(p);
}
if (vfexec || spawn) {
old_map = vm_map_switch(get_task_map(task));
}
if (load_result.unixproc) {
user_addr_t ap;
ap = p->user_stack;
error = exec_copyout_strings(imgp, &ap);
if (error) {
if (vfexec || spawn)
vm_map_switch(old_map);
goto badtoolate;
}
thread_setuserstack(thread, ap);
}
if (load_result.dynlinker) {
uint64_t ap;
if (imgp->ip_flags & IMGPF_IS_64BIT) {
ap = thread_adjuserstack(thread, -8);
error = copyoutptr(load_result.mach_header, ap, 8);
} else {
ap = thread_adjuserstack(thread, -4);
error = suword(ap, load_result.mach_header);
}
if (error) {
if (vfexec || spawn)
vm_map_switch(old_map);
goto badtoolate;
}
task_set_dyld_info(task, load_result.all_image_info_addr,
load_result.all_image_info_size);
}
if (vfexec || spawn) {
vm_map_switch(old_map);
}
thread_setentrypoint(thread, load_result.entry_point);
stopprofclock(p);
execsigs(p, thread);
_aio_exec( p );
#if SYSV_SHM
if (!vfexec && p->vm_shm)
shmexec(p);
#endif
#if SYSV_SEM
semexit(p);
#endif
p->p_acflag &= ~AFORK;
if (0 != imgp->ip_p_comm[0]) {
bcopy((caddr_t)imgp->ip_p_comm, (caddr_t)p->p_comm,
sizeof(p->p_comm));
} else {
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';
}
memcpy(&p->p_uuid[0], &load_result.uuid[0], sizeof(p->p_uuid));
#if CONFIG_DTRACE
dtrace_set_thread_predcache(current_thread(), 0);
dtrace_lazy_dofs_destroy(p);
if (p->p_dtrace_helpers != NULL && dtrace_helpers_cleanup) {
(*dtrace_helpers_cleanup)(p);
}
proc_lock(p);
if (p->p_dtrace_probes && dtrace_fasttrap_exec_ptr) {
(*dtrace_fasttrap_exec_ptr)(p);
}
proc_unlock(p);
#endif
if (kdebug_enable) {
long dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4;
kdbg_trace_string(p, &dbg_arg1, &dbg_arg2, &dbg_arg3, &dbg_arg4);
if (vfexec || spawn) {
KERNEL_DEBUG_CONSTANT1((TRACEDBG_CODE(DBG_TRACE_DATA, 2)) | DBG_FUNC_NONE,
p->p_pid ,0,0,0, (uintptr_t)thread_tid(thread));
KERNEL_DEBUG_CONSTANT1((TRACEDBG_CODE(DBG_TRACE_STRING, 2)) | DBG_FUNC_NONE,
dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, (uintptr_t)thread_tid(thread));
} else {
KERNEL_DEBUG_CONSTANT((TRACEDBG_CODE(DBG_TRACE_DATA, 2)) | DBG_FUNC_NONE,
p->p_pid ,0,0,0,0);
KERNEL_DEBUG_CONSTANT((TRACEDBG_CODE(DBG_TRACE_STRING, 2)) | DBG_FUNC_NONE,
dbg_arg1, dbg_arg2, dbg_arg3, dbg_arg4, 0);
}
}
#ifdef IMGPF_POWERPC
if (((imgp->ip_flags & IMGPF_POWERPC) != 0))
OSBitOrAtomic(P_TRANSLATED, &p->p_flag);
else
#endif
OSBitAndAtomic(~((uint32_t)P_TRANSLATED), &p->p_flag);
OSBitAndAtomic(~((uint32_t)P_AFFINITY), &p->p_flag);
if (imgp->ip_px_sa != NULL) {
psa = (struct _posix_spawnattr *) imgp->ip_px_sa;
if (psa->psa_flags & POSIX_SPAWN_START_SUSPENDED) {
proc_lock(p);
p->p_stat = SSTOP;
proc_unlock(p);
(void) task_suspend(p->task);
}
}
OSBitOrAtomic(P_EXEC, &p->p_flag);
proc_resetregister(p);
if (p->p_pptr && (p->p_lflag & P_LPPWAIT)) {
proc_lock(p);
p->p_lflag &= ~P_LPPWAIT;
proc_unlock(p);
wakeup((caddr_t)p->p_pptr);
}
if (vfexec && (p->p_lflag & P_LTRACED)) {
psignal_vfork(p, new_task, thread, SIGTRAP);
}
badtoolate:
if (!spawn)
proc_knote(p, NOTE_EXEC);
if (vfexec || spawn) {
task_deallocate(new_task);
thread_deallocate(thread);
if (error)
error = 0;
}
bad:
return(error);
}
struct execsw {
int (*ex_imgact)(struct image_params *);
const char *ex_name;
} execsw[] = {
{ exec_mach_imgact, "Mach-o Binary" },
{ exec_fat_imgact, "Fat Binary" },
#ifdef IMGPF_POWERPC
{ exec_powerpc32_imgact, "PowerPC binary" },
#endif
{ exec_shell_imgact, "Interpreter Script" },
{ NULL, NULL}
};
static int
exec_activate_image(struct image_params *imgp)
{
struct nameidata nd;
int error;
int resid;
int once = 1;
int i;
int iterlimit = EAI_ITERLIMIT;
proc_t p = vfs_context_proc(imgp->ip_vfs_context);
error = execargs_alloc(imgp);
if (error)
goto bad;
error = exec_save_path(imgp, imgp->ip_user_fname, imgp->ip_seg);
if (error) {
goto bad_notrans;
}
DTRACE_PROC1(exec, uintptr_t, imgp->ip_strings);
NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNPATH1,
imgp->ip_seg, imgp->ip_user_fname, imgp->ip_vfs_context);
again:
error = namei(&nd);
if (error)
goto bad_notrans;
imgp->ip_ndp = &nd;
imgp->ip_vp = nd.ni_vp;
error = proc_transstart(p, 0);
if (error)
goto bad_notrans;
error = exec_check_permissions(imgp);
if (error)
goto bad;
if (once) {
once = 0;
*imgp->ip_origvattr = *imgp->ip_vattr;
}
error = vn_rdwr(UIO_READ, imgp->ip_vp, imgp->ip_vdata, PAGE_SIZE, 0,
UIO_SYSSPACE, IO_NODELOCKED,
vfs_context_ucred(imgp->ip_vfs_context),
&resid, vfs_context_proc(imgp->ip_vfs_context));
if (error)
goto bad;
encapsulated_binary:
if (--iterlimit == 0) {
error = EBADEXEC;
goto bad;
}
error = -1;
for(i = 0; error == -1 && execsw[i].ex_imgact != NULL; i++) {
error = (*execsw[i].ex_imgact)(imgp);
switch (error) {
case -2:
goto encapsulated_binary;
case -3:
#if CONFIG_MACF
if (imgp->ip_scriptlabelp)
mac_vnode_label_free(imgp->ip_scriptlabelp);
imgp->ip_scriptlabelp = mac_vnode_label_alloc();
if (imgp->ip_scriptlabelp == NULL) {
error = ENOMEM;
break;
}
mac_vnode_label_copy(imgp->ip_vp->v_label,
imgp->ip_scriptlabelp);
#endif
vnode_put(imgp->ip_vp);
imgp->ip_vp = NULL;
NDINIT(&nd, LOOKUP, (nd.ni_cnd.cn_flags & HASBUF) | (FOLLOW | LOCKLEAF),
UIO_SYSSPACE, CAST_USER_ADDR_T(imgp->ip_interp_name), imgp->ip_vfs_context);
#ifdef IMGPF_POWERPC
if (imgp->ip_flags & IMGPF_POWERPC)
nd.ni_cnd.cn_flags &= ~FOLLOW;
#endif
proc_transend(p, 0);
goto again;
default:
break;
}
}
if (error == 0 && kauth_authorize_fileop_has_listeners()) {
kauth_authorize_fileop(vfs_context_ucred(imgp->ip_vfs_context),
KAUTH_FILEOP_EXEC,
(uintptr_t)nd.ni_vp, 0);
}
bad:
proc_transend(p, 0);
bad_notrans:
if (imgp->ip_strings)
execargs_free(imgp);
if (imgp->ip_ndp)
nameidone(imgp->ip_ndp);
return (error);
}
static int
exec_handle_port_actions(struct image_params *imgp, short psa_flags)
{
_posix_spawn_port_actions_t pacts = imgp->ip_px_spa;
proc_t p = vfs_context_proc(imgp->ip_vfs_context);
_ps_port_action_t *act = NULL;
task_t task = p->task;
ipc_port_t port = NULL;
kern_return_t ret = KERN_SUCCESS;
int i;
for (i = 0; i < pacts->pspa_count; i++) {
act = &pacts->pspa_actions[i];
ret = ipc_object_copyin(get_task_ipcspace(current_task()),
CAST_MACH_PORT_TO_NAME(act->new_port),
MACH_MSG_TYPE_COPY_SEND,
(ipc_object_t *) &port);
if (ret)
return ret;
switch (act->port_type) {
case PSPA_SPECIAL:
if (!(psa_flags & POSIX_SPAWN_SETEXEC))
return ENOTSUP;
ret = task_set_special_port(task,
act->which,
port);
break;
case PSPA_EXCEPTION:
if (!(psa_flags & POSIX_SPAWN_SETEXEC))
return ENOTSUP;
ret = task_set_exception_ports(task,
act->mask,
port,
act->behavior,
act->flavor);
break;
#if CONFIG_AUDIT
case PSPA_AU_SESSION:
ret = audit_session_spawnjoin(p,
port);
break;
#endif
default:
ret = KERN_FAILURE;
}
if (ret) {
ipc_port_release_send(port);
return ret;
}
}
return ret;
}
static int
exec_handle_file_actions(struct image_params *imgp)
{
int error = 0;
int action;
proc_t p = vfs_context_proc(imgp->ip_vfs_context);
_posix_spawn_file_actions_t px_sfap = imgp->ip_px_sfa;
int ival[2];
for (action = 0; action < px_sfap->psfa_act_count; action++) {
_psfa_action_t *psfa = &px_sfap->psfa_act_acts[ action];
switch(psfa->psfaa_type) {
case PSFA_OPEN: {
struct vnode_attr va;
struct nameidata nd;
int mode = psfa->psfaa_openargs.psfao_mode;
struct dup2_args dup2a;
struct close_nocancel_args ca;
int origfd;
VATTR_INIT(&va);
mode = ((mode &~ p->p_fd->fd_cmask) & ALLPERMS) & ~S_ISTXT;
VATTR_SET(&va, va_mode, mode & ACCESSPERMS);
NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNPATH1, UIO_SYSSPACE,
CAST_USER_ADDR_T(psfa->psfaa_openargs.psfao_path),
imgp->ip_vfs_context);
error = open1(imgp->ip_vfs_context,
&nd,
psfa->psfaa_openargs.psfao_oflag,
&va,
ival);
if (error || ival[0] == psfa->psfaa_filedes)
break;
origfd = ival[0];
dup2a.from = origfd;
dup2a.to = psfa->psfaa_filedes;
error = dup2(p, &dup2a, ival);
if (error)
break;
ca.fd = origfd;
error = close_nocancel(p, &ca, ival);
}
break;
case PSFA_DUP2: {
struct dup2_args dup2a;
dup2a.from = psfa->psfaa_filedes;
dup2a.to = psfa->psfaa_openargs.psfao_oflag;
error = dup2(p, &dup2a, ival);
}
break;
case PSFA_CLOSE: {
struct close_nocancel_args ca;
ca.fd = psfa->psfaa_filedes;
error = close_nocancel(p, &ca, ival);
}
break;
default:
error = EINVAL;
break;
}
if (error)
break;
}
return (error);
}
int
posix_spawn(proc_t ap, struct posix_spawn_args *uap, int32_t *retval)
{
proc_t p = ap;
user_addr_t pid = uap->pid;
int ival[2];
char *bufp = NULL;
struct image_params *imgp;
struct vnode_attr *vap;
struct vnode_attr *origvap;
struct uthread *uthread = 0;
int error, sig;
char alt_p_comm[sizeof(p->p_comm)] = {0};
int is_64 = IS_64BIT_PROCESS(p);
struct vfs_context context;
struct user__posix_spawn_args_desc px_args;
struct _posix_spawnattr px_sa;
_posix_spawn_file_actions_t px_sfap = NULL;
_posix_spawn_port_actions_t px_spap = NULL;
struct __kern_sigaction vec;
boolean_t spawn_no_exec = FALSE;
MALLOC(bufp, char *, (sizeof(*imgp) + sizeof(*vap) + sizeof(*origvap)), M_TEMP, M_WAITOK | M_ZERO);
imgp = (struct image_params *) bufp;
if (bufp == NULL) {
error = ENOMEM;
goto bad;
}
vap = (struct vnode_attr *) (bufp + sizeof(*imgp));
origvap = (struct vnode_attr *) (bufp + sizeof(*imgp) + sizeof(*vap));
imgp->ip_user_fname = uap->path;
imgp->ip_user_argv = uap->argv;
imgp->ip_user_envv = uap->envp;
imgp->ip_vattr = vap;
imgp->ip_origvattr = origvap;
imgp->ip_vfs_context = &context;
imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT : IMGPF_NONE);
imgp->ip_p_comm = alt_p_comm;
imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
if (uap->adesc != USER_ADDR_NULL) {
if(is_64) {
error = copyin(uap->adesc, &px_args, sizeof(px_args));
} else {
struct user32__posix_spawn_args_desc px_args32;
error = copyin(uap->adesc, &px_args32, sizeof(px_args32));
px_args.attr_size = px_args32.attr_size;
px_args.attrp = CAST_USER_ADDR_T(px_args32.attrp);
px_args.file_actions_size = px_args32.file_actions_size;
px_args.file_actions = CAST_USER_ADDR_T(px_args32.file_actions);
px_args.port_actions_size = px_args32.port_actions_size;
px_args.port_actions = CAST_USER_ADDR_T(px_args32.port_actions);
}
if (error)
goto bad;
if (px_args.attr_size != 0) {
if ((error = copyin(px_args.attrp, &px_sa, sizeof(px_sa))) != 0)
goto bad;
imgp->ip_px_sa = &px_sa;
}
if (px_args.file_actions_size != 0) {
int maxfa = (p->p_limit ? p->p_rlimit[RLIMIT_NOFILE].rlim_cur : NOFILE);
if (px_args.file_actions_size < PSF_ACTIONS_SIZE(1) ||
px_args.file_actions_size > PSF_ACTIONS_SIZE(maxfa)) {
error = EINVAL;
goto bad;
}
MALLOC(px_sfap, _posix_spawn_file_actions_t, px_args.file_actions_size, M_TEMP, M_WAITOK);
if (px_sfap == NULL) {
error = ENOMEM;
goto bad;
}
imgp->ip_px_sfa = px_sfap;
if ((error = copyin(px_args.file_actions, px_sfap,
px_args.file_actions_size)) != 0)
goto bad;
}
if (px_args.port_actions_size != 0) {
if (px_args.port_actions_size < PS_PORT_ACTIONS_SIZE(1) ||
px_args.port_actions_size > PAGE_SIZE) {
error = EINVAL;
goto bad;
}
MALLOC(px_spap, _posix_spawn_port_actions_t,
px_args.port_actions_size, M_TEMP, M_WAITOK);
if (px_spap == NULL) {
error = ENOMEM;
goto bad;
}
imgp->ip_px_spa = px_spap;
if ((error = copyin(px_args.port_actions, px_spap,
px_args.port_actions_size)) != 0)
goto bad;
}
}
uthread = get_bsdthread_info(current_thread());
if (uthread->uu_flag & UT_VFORK) {
error = EINVAL;
goto bad;
}
if (imgp->ip_px_sa == NULL || !(px_sa.psa_flags & POSIX_SPAWN_SETEXEC)){
if ((error = fork1(p, &imgp->ip_new_thread, PROC_CREATE_SPAWN)) != 0)
goto bad;
imgp->ip_flags |= IMGPF_SPAWN;
spawn_no_exec = TRUE;
}
if (spawn_no_exec)
p = (proc_t)get_bsdthreadtask_info(imgp->ip_new_thread);
context.vc_thread = current_thread();
context.vc_ucred = p->p_ucred;
if (spawn_no_exec)
context.vc_thread = imgp->ip_new_thread;
if (imgp->ip_px_sfa != NULL &&
(error = exec_handle_file_actions(imgp)) != 0) {
goto bad;
}
if (imgp->ip_px_spa != NULL) {
if((error = exec_handle_port_actions(imgp, px_sa.psa_flags)) != 0)
goto bad;
}
if (imgp->ip_px_sa != NULL) {
if (px_sa.psa_flags & POSIX_SPAWN_SETPGROUP) {
struct setpgid_args spga;
spga.pid = p->p_pid;
spga.pgid = px_sa.psa_pgroup;
if((error = setpgid(p, &spga, ival)) != 0)
goto bad;
}
if (px_sa.psa_flags & POSIX_SPAWN_RESETIDS) {
kauth_cred_t my_cred = p->p_ucred;
kauth_cred_t my_new_cred = kauth_cred_setuidgid(my_cred, my_cred->cr_ruid, my_cred->cr_rgid);
if (my_new_cred != my_cred)
p->p_ucred = my_new_cred;
}
}
if (spawn_no_exec) {
proc_transend(p, 0);
}
#if MAC_SPAWN
if (uap->mac_p != USER_ADDR_NULL) {
error = mac_execve_enter(uap->mac_p, imgp);
if (error)
goto bad;
}
#endif
error = exec_activate_image(imgp);
if (error == -1)
error = ENOEXEC;
if (!error && imgp->ip_px_sa != NULL) {
thread_t child_thread = current_thread();
uthread_t child_uthread = uthread;
if (spawn_no_exec) {
child_thread = imgp->ip_new_thread;
child_uthread = get_bsdthread_info(child_thread);
}
if (px_sa.psa_flags & POSIX_SPAWN_SETSIGMASK)
child_uthread->uu_sigmask = (px_sa.psa_sigmask & ~sigcantmask);
if (px_sa.psa_flags & POSIX_SPAWN_SETSIGDEF) {
vec.sa_handler = SIG_DFL;
vec.sa_tramp = 0;
vec.sa_mask = 0;
vec.sa_flags = 0;
for (sig = 0; sig < NSIG; sig++)
if (px_sa.psa_sigdefault & (1 << sig)) {
error = setsigvec(p, child_thread, sig + 1, &vec, spawn_no_exec);
}
}
}
bad:
if (error == 0) {
if (imgp->ip_px_sa != NULL) {
switch (px_sa.psa_pcontrol) {
case POSIX_SPAWN_PCONTROL_THROTTLE:
p->p_pcaction = P_PCTHROTTLE;
break;
case POSIX_SPAWN_PCONTROL_SUSPEND:
p->p_pcaction = P_PCSUSP;
break;
case POSIX_SPAWN_PCONTROL_KILL:
p->p_pcaction = P_PCKILL;
break;
case POSIX_SPAWN_PCONTROL_NONE:
default:
p->p_pcaction = 0;
break;
};
}
exec_resettextvp(p, imgp);
}
if (spawn_no_exec) {
proc_signalend(p, 0);
proc_knote(p->p_pptr, NOTE_FORK | p->p_pid);
proc_knote(p, NOTE_EXEC);
DTRACE_PROC1(create, proc_t, p);
}
if (error == 0) {
error = check_for_signature(p, imgp);
if (imgp != NULL && spawn_no_exec && (p->p_lflag & P_LTRACED)) {
psignal_vfork(p, p->task, imgp->ip_new_thread, SIGTRAP);
}
}
if (imgp != NULL) {
if (imgp->ip_vp)
vnode_put(imgp->ip_vp);
if (imgp->ip_strings)
execargs_free(imgp);
if (imgp->ip_px_sfa != NULL)
FREE(imgp->ip_px_sfa, M_TEMP);
if (imgp->ip_px_spa != NULL)
FREE(imgp->ip_px_spa, M_TEMP);
#if CONFIG_MACF
if (imgp->ip_execlabelp)
mac_cred_label_free(imgp->ip_execlabelp);
if (imgp->ip_scriptlabelp)
mac_vnode_label_free(imgp->ip_scriptlabelp);
#endif
}
if (error) {
DTRACE_PROC1(exec__failure, int, error);
} else {
if (imgp != NULL && imgp->ip_flags & IMGPF_SPAWN) {
p->p_lflag |= P_LINVFORK;
p->p_vforkact = current_thread();
uthread->uu_proc = p;
uthread->uu_flag |= UT_VFORK;
}
DTRACE_PROC(exec__success);
if (imgp != NULL && imgp->ip_flags & IMGPF_SPAWN) {
p->p_lflag &= ~P_LINVFORK;
p->p_vforkact = NULL;
uthread->uu_proc = PROC_NULL;
uthread->uu_flag &= ~UT_VFORK;
}
}
if (imgp != NULL && spawn_no_exec) {
if (pid != USER_ADDR_NULL)
(void)suword(pid, p->p_pid);
retval[0] = error;
if (error) {
proc_list_lock();
p->p_listflag |= P_LIST_DEADPARENT;
proc_list_unlock();
proc_lock(p);
if (p->p_stat != SZOMB && p->exit_thread == NULL) {
p->exit_thread = current_thread();
proc_unlock(p);
exit1(p, 1, (int *)NULL);
task_deallocate(get_threadtask(imgp->ip_new_thread));
thread_deallocate(imgp->ip_new_thread);
} else {
proc_unlock(p);
}
} else {
(void)thread_resume(imgp->ip_new_thread);
}
}
if (bufp != NULL) {
FREE(bufp, M_TEMP);
}
return(error);
}
int
execve(proc_t p, struct execve_args *uap, int32_t *retval)
{
struct __mac_execve_args muap;
int err;
muap.fname = uap->fname;
muap.argp = uap->argp;
muap.envp = uap->envp;
muap.mac_p = USER_ADDR_NULL;
err = __mac_execve(p, &muap, retval);
return(err);
}
int
__mac_execve(proc_t p, struct __mac_execve_args *uap, int32_t *retval)
{
char *bufp = NULL;
struct image_params *imgp;
struct vnode_attr *vap;
struct vnode_attr *origvap;
int error;
char alt_p_comm[sizeof(p->p_comm)] = {0};
int is_64 = IS_64BIT_PROCESS(p);
struct vfs_context context;
context.vc_thread = current_thread();
context.vc_ucred = kauth_cred_proc_ref(p);
MALLOC(bufp, char *, (sizeof(*imgp) + sizeof(*vap) + sizeof(*origvap)), M_TEMP, M_WAITOK | M_ZERO);
imgp = (struct image_params *) bufp;
if (bufp == NULL) {
error = ENOMEM;
goto exit_with_error;
}
vap = (struct vnode_attr *) (bufp + sizeof(*imgp));
origvap = (struct vnode_attr *) (bufp + sizeof(*imgp) + sizeof(*vap));
imgp->ip_user_fname = uap->fname;
imgp->ip_user_argv = uap->argp;
imgp->ip_user_envv = uap->envp;
imgp->ip_vattr = vap;
imgp->ip_origvattr = origvap;
imgp->ip_vfs_context = &context;
imgp->ip_flags = (is_64 ? IMGPF_WAS_64BIT : IMGPF_NONE);
imgp->ip_p_comm = alt_p_comm;
imgp->ip_seg = (is_64 ? UIO_USERSPACE64 : UIO_USERSPACE32);
#if CONFIG_MACF
if (uap->mac_p != USER_ADDR_NULL) {
error = mac_execve_enter(uap->mac_p, imgp);
if (error) {
kauth_cred_unref(&context.vc_ucred);
goto exit_with_error;
}
}
#endif
error = exec_activate_image(imgp);
kauth_cred_unref(&context.vc_ucred);
if (error == -1)
error = ENOEXEC;
if (error == 0) {
exec_resettextvp(p, imgp);
error = check_for_signature(p, imgp);
}
if (imgp->ip_vp != NULLVP)
vnode_put(imgp->ip_vp);
if (imgp->ip_strings)
execargs_free(imgp);
#if CONFIG_MACF
if (imgp->ip_execlabelp)
mac_cred_label_free(imgp->ip_execlabelp);
if (imgp->ip_scriptlabelp)
mac_vnode_label_free(imgp->ip_scriptlabelp);
#endif
if (!error) {
struct uthread *uthread;
thread_affinity_exec(current_thread());
DTRACE_PROC(exec__success);
uthread = get_bsdthread_info(current_thread());
if (uthread->uu_flag & UT_VFORK) {
vfork_return(p, retval, p->p_pid);
(void)thread_resume(imgp->ip_new_thread);
}
} else {
DTRACE_PROC1(exec__failure, int, error);
}
exit_with_error:
if (bufp != NULL) {
FREE(bufp, M_TEMP);
}
return(error);
}
static int
copyinptr(user_addr_t froma, user_addr_t *toptr, int ptr_size)
{
int error;
if (ptr_size == 4) {
unsigned int i;
error = copyin(froma, &i, 4);
*toptr = CAST_USER_ADDR_T(i);
} else {
error = copyin(froma, toptr, 8);
}
return (error);
}
static int
copyoutptr(user_addr_t ua, user_addr_t ptr, int ptr_size)
{
int error;
if (ptr_size == 4) {
unsigned int i = CAST_DOWN_EXPLICIT(unsigned int,ua);
error = copyout(&i, ptr, 4);
} else {
error = copyout(&ua, ptr, 8);
}
return (error);
}
static int
exec_copyout_strings(struct image_params *imgp, user_addr_t *stackp)
{
proc_t p = vfs_context_proc(imgp->ip_vfs_context);
int ptr_size = (imgp->ip_flags & IMGPF_IS_64BIT) ? 8 : 4;
char *argv = imgp->ip_argv;
user_addr_t string_area;
user_addr_t path_area;
user_addr_t ptr_area;
user_addr_t stack;
int stringc = imgp->ip_argc + imgp->ip_envc;
size_t len;
int error;
ssize_t strspace;
stack = *stackp;
size_t patharea_len = imgp->ip_argv - imgp->ip_strings;
int envc_add = 0;
string_area = stack - (((imgp->ip_strendp - imgp->ip_strings) + ptr_size-1) & ~(ptr_size-1)) - ptr_size;
path_area = string_area - ((patharea_len + ptr_size-1) & ~(ptr_size-1));
ptr_area = path_area - ((imgp->ip_argc + imgp->ip_envc + 4 + envc_add) * ptr_size) - ptr_size ;
*stackp = ptr_area;
proc_lock(p);
p->p_argc = imgp->ip_argc;
p->p_argslen = (int)(stack - path_area);
proc_unlock(p);
len = 0;
error = copyoutstr(imgp->ip_strings, path_area,
patharea_len,
&len);
if (error)
goto bad;
(void)copyoutptr(0LL, path_area - ptr_size, ptr_size);
(void)copyoutptr(path_area, path_area - 2*ptr_size, ptr_size);
(void)suword(ptr_area, imgp->ip_argc);
ptr_area += sizeof(int);
if (imgp->ip_flags & IMGPF_IS_64BIT) {
(void)suword(ptr_area, 0);
ptr_area += sizeof(int);
}
#if CONFIG_DTRACE
p->p_dtrace_argv = ptr_area;
#endif
strspace = SIZE_IMG_STRSPACE - (string_area - path_area);
for (;;) {
if (stringc == imgp->ip_envc) {
(void)copyoutptr(0LL, ptr_area, ptr_size);
ptr_area += ptr_size;
#if CONFIG_DTRACE
p->p_dtrace_envp = ptr_area;
#endif
}
if (--stringc < 0)
break;
(void)copyoutptr(string_area, ptr_area, ptr_size);
do {
if (strspace <= 0) {
error = E2BIG;
break;
}
error = copyoutstr(argv, string_area,
strspace,
&len);
string_area += len;
argv += len;
strspace -= len;
} while (error == ENAMETOOLONG);
if (error == EFAULT || error == E2BIG)
break;
ptr_area += ptr_size;
}
(void)copyoutptr(0LL, ptr_area, ptr_size);
bad:
return(error);
}
static int
exec_extract_strings(struct image_params *imgp)
{
int error = 0;
int strsz = 0;
int ptr_size = (imgp->ip_flags & IMGPF_WAS_64BIT) ? 8 : 4;
user_addr_t argv = imgp->ip_user_argv;
user_addr_t envv = imgp->ip_user_envv;
if (imgp->ip_user_argv == 0LL)
goto bad;
strsz = strlen(imgp->ip_strings) + 1;
imgp->ip_strspace -= ((strsz + ptr_size-1) & ~(ptr_size-1)) - strsz;
if((imgp->ip_flags & IMGPF_INTERPRET) != 0 && argv != 0LL) {
user_addr_t arg;
error = copyinptr(argv, &arg, ptr_size);
if (error)
goto bad;
if (arg != 0LL && arg != (user_addr_t)-1) {
argv += ptr_size;
error = exec_add_string(imgp, imgp->ip_user_fname);
if (error)
goto bad;
imgp->ip_argc++;
}
}
while (argv != 0LL) {
user_addr_t arg;
error = copyinptr(argv, &arg, ptr_size);
if (error)
goto bad;
argv += ptr_size;
if (arg == 0LL) {
break;
} else if (arg == (user_addr_t)-1) {
error = EFAULT;
goto bad;
}
error = exec_add_string(imgp, arg);
if (error)
goto bad;
imgp->ip_argc++;
}
imgp->ip_strendargvp = imgp->ip_strendp;
while (envv != 0LL) {
user_addr_t env;
error = copyinptr(envv, &env, ptr_size);
if (error)
goto bad;
envv += ptr_size;
if (env == 0LL) {
break;
} else if (env == (user_addr_t)-1) {
error = EFAULT;
goto bad;
}
error = exec_add_string(imgp, env);
if (error)
goto bad;
imgp->ip_envc++;
}
bad:
return error;
}
#define unix_stack_size(p) (p->p_rlimit[RLIMIT_STACK].rlim_cur)
static int
exec_check_permissions(struct image_params *imgp)
{
struct vnode *vp = imgp->ip_vp;
struct vnode_attr *vap = imgp->ip_vattr;
proc_t p = vfs_context_proc(imgp->ip_vfs_context);
int error;
kauth_action_t action;
if (!vnode_isreg(vp))
return (EACCES);
VATTR_INIT(vap);
VATTR_WANTED(vap, va_uid);
VATTR_WANTED(vap, va_gid);
VATTR_WANTED(vap, va_mode);
VATTR_WANTED(vap, va_fsid);
VATTR_WANTED(vap, va_fileid);
VATTR_WANTED(vap, va_data_size);
if ((error = vnode_getattr(vp, vap, imgp->ip_vfs_context)) != 0)
return (error);
if ((vap->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0)
return (EACCES);
if (vap->va_data_size == 0)
return (ENOEXEC);
imgp->ip_arch_offset = (user_size_t)0;
imgp->ip_arch_size = vap->va_data_size;
if ((vp->v_mount->mnt_flag & MNT_NOSUID) || (p->p_lflag & P_LTRACED))
vap->va_mode &= ~(VSUID | VSGID);
#if CONFIG_MACF
error = mac_vnode_check_exec(imgp->ip_vfs_context, vp, imgp);
if (error)
return (error);
#endif
action = KAUTH_VNODE_EXECUTE;
if (p->p_lflag & P_LTRACED)
action |= KAUTH_VNODE_READ_DATA;
if ((error = vnode_authorize(vp, NULL, action, imgp->ip_vfs_context)) != 0)
return (error);
#if 0
vnode_lock(vp);
if (vp->v_writecount) {
panic("going to return ETXTBSY %x", vp);
vnode_unlock(vp);
return (ETXTBSY);
}
vnode_unlock(vp);
#endif
#ifdef IMGPF_POWERPC
if (vap->va_fsid == exec_archhandler_ppc.fsid &&
vap->va_fileid == (uint64_t)((uint32_t)exec_archhandler_ppc.fileid)) {
imgp->ip_flags |= IMGPF_POWERPC;
}
#endif
return (error);
}
static int
exec_handle_sugid(struct image_params *imgp)
{
kauth_cred_t cred = vfs_context_ucred(imgp->ip_vfs_context);
proc_t p = vfs_context_proc(imgp->ip_vfs_context);
int i;
int leave_sugid_clear = 0;
int error = 0;
struct vnode *dev_null = NULLVP;
#if CONFIG_MACF
int mac_transition;
mac_transition = mac_cred_check_label_update_execve(
imgp->ip_vfs_context,
imgp->ip_vp,
imgp->ip_scriptlabelp,
imgp->ip_execlabelp, p);
#endif
OSBitAndAtomic(~((uint32_t)P_SUGID), &p->p_flag);
if (((imgp->ip_origvattr->va_mode & VSUID) != 0 &&
kauth_cred_getuid(cred) != imgp->ip_origvattr->va_uid) ||
((imgp->ip_origvattr->va_mode & VSGID) != 0 &&
((kauth_cred_ismember_gid(cred, imgp->ip_origvattr->va_gid, &leave_sugid_clear) || !leave_sugid_clear) ||
(cred->cr_gid != imgp->ip_origvattr->va_gid)))) {
#if CONFIG_MACF
handle_mac_transition:
#endif
if (imgp->ip_origvattr->va_mode & VSUID) {
p->p_ucred = kauth_cred_setresuid(p->p_ucred, KAUTH_UID_NONE, imgp->ip_origvattr->va_uid, imgp->ip_origvattr->va_uid, KAUTH_UID_NONE);
}
if (imgp->ip_origvattr->va_mode & VSGID) {
p->p_ucred = kauth_cred_setresgid(p->p_ucred, KAUTH_GID_NONE, imgp->ip_origvattr->va_gid, imgp->ip_origvattr->va_gid);
}
#if CONFIG_MACF
if (mac_transition) {
kauth_cred_t my_cred;
if (kauth_proc_label_update_execve(p,
imgp->ip_vfs_context,
imgp->ip_vp,
imgp->ip_scriptlabelp,
imgp->ip_execlabelp)) {
leave_sugid_clear = 0;
}
my_cred = kauth_cred_proc_ref(p);
mac_task_label_update_cred(my_cred, p->task);
kauth_cred_unref(&my_cred);
}
#endif
ipc_task_reset(p->task);
ipc_thread_reset((imgp->ip_new_thread != NULL) ?
imgp->ip_new_thread : current_thread());
if (!leave_sugid_clear)
OSBitOrAtomic(P_SUGID, &p->p_flag);
if (dev_null == NULLVP) {
struct nameidata nd1;
NDINIT(&nd1, LOOKUP, FOLLOW, UIO_SYSSPACE,
CAST_USER_ADDR_T("/dev/null"),
imgp->ip_vfs_context);
if ((error = vn_open(&nd1, FREAD, 0)) == 0) {
dev_null = nd1.ni_vp;
vnode_put(nd1.ni_vp);
}
}
if (dev_null != NULLVP) {
for (i = 0; i < 3; i++) {
struct fileproc *fp;
int indx;
if (p->p_fd->fd_ofiles[i] != NULL)
continue;
if ((error = falloc(p, &fp, &indx, imgp->ip_vfs_context)) != 0)
continue;
if ((error = vnode_ref_ext(dev_null, FREAD)) != 0) {
fp_free(p, indx, fp);
break;
}
fp->f_fglob->fg_flag = FREAD;
fp->f_fglob->fg_type = DTYPE_VNODE;
fp->f_fglob->fg_ops = &vnops;
fp->f_fglob->fg_data = (caddr_t)dev_null;
proc_fdlock(p);
procfdtbl_releasefd(p, indx, NULL);
fp_drop(p, indx, fp, 1);
proc_fdunlock(p);
}
vnode_rele(dev_null);
dev_null = NULLVP;
}
}
#if CONFIG_MACF
else {
if (mac_transition) {
leave_sugid_clear = 1;
goto handle_mac_transition;
}
}
#endif
p->p_ucred = kauth_cred_setsvuidgid(p->p_ucred, kauth_cred_getuid(p->p_ucred), p->p_ucred->cr_gid);
p->p_idversion++;
set_security_token(p);
return(error);
}
static kern_return_t
create_unix_stack(vm_map_t map, user_addr_t user_stack, int customstack,
proc_t p)
{
mach_vm_size_t size, prot_size;
mach_vm_offset_t addr, prot_addr;
kern_return_t kr;
proc_lock(p);
p->user_stack = user_stack;
proc_unlock(p);
if (!customstack) {
size = mach_vm_round_page(MAXSSIZ);
#if STACK_GROWTH_UP
addr = mach_vm_trunc_page(user_stack);
#else
addr = mach_vm_trunc_page(user_stack - size);
#endif
kr = mach_vm_allocate(map, &addr, size,
VM_MAKE_TAG(VM_MEMORY_STACK) |
VM_FLAGS_FIXED);
if (kr != KERN_SUCCESS) {
return kr;
}
prot_addr = addr;
#if STACK_GROWTH_UP
prot_addr += unix_stack_size(p);
#endif
prot_addr = mach_vm_round_page(prot_addr);
prot_size = mach_vm_trunc_page(size - unix_stack_size(p));
kr = mach_vm_protect(map,
prot_addr,
prot_size,
FALSE,
VM_PROT_NONE);
if (kr != KERN_SUCCESS) {
(void) mach_vm_deallocate(map, addr, size);
return kr;
}
}
return KERN_SUCCESS;
}
#include <sys/reboot.h>
static char init_program_name[128] = "/sbin/launchd";
struct execve_args init_exec_args;
void
load_init_program(proc_t p)
{
vm_offset_t init_addr;
int argc = 0;
uint32_t argv[3];
int error;
int retval[2];
init_addr = VM_MIN_ADDRESS;
(void) vm_allocate(current_map(), &init_addr, PAGE_SIZE,
VM_FLAGS_ANYWHERE);
if (init_addr == 0)
init_addr++;
(void) copyout((caddr_t) init_program_name, CAST_USER_ADDR_T(init_addr),
(unsigned) sizeof(init_program_name)+1);
argv[argc++] = (uint32_t)init_addr;
init_addr += sizeof(init_program_name);
init_addr = (vm_offset_t)ROUND_PTR(char, init_addr);
if (boothowto & RB_SINGLE) {
const char *init_args = "-s";
copyout(init_args, CAST_USER_ADDR_T(init_addr),
strlen(init_args));
argv[argc++] = (uint32_t)init_addr;
init_addr += strlen(init_args);
init_addr = (vm_offset_t)ROUND_PTR(char, init_addr);
}
argv[argc] = 0;
(void) copyout((caddr_t) argv, CAST_USER_ADDR_T(init_addr),
(unsigned) sizeof(argv));
init_exec_args.fname = CAST_USER_ADDR_T(argv[0]);
init_exec_args.argp = CAST_USER_ADDR_T((char **)init_addr);
init_exec_args.envp = CAST_USER_ADDR_T(0);
set_security_token(p);
error = execve(p,&init_exec_args,retval);
if (error)
panic("Process 1 exec of %s failed, errno %d\n",
init_program_name, error);
}
static int
load_return_to_errno(load_return_t lrtn)
{
switch (lrtn) {
case LOAD_SUCCESS:
return 0;
case LOAD_BADARCH:
return EBADARCH;
case LOAD_BADMACHO:
return EBADMACHO;
case LOAD_SHLIB:
return ESHLIBVERS;
case LOAD_NOSPACE:
case LOAD_RESOURCE:
return ENOMEM;
case LOAD_PROTECT:
return EACCES;
case LOAD_ENOENT:
return ENOENT;
case LOAD_IOERROR:
return EIO;
case LOAD_FAILURE:
default:
return EBADEXEC;
}
}
#include <mach/mach_types.h>
#include <mach/vm_prot.h>
#include <mach/semaphore.h>
#include <mach/sync_policy.h>
#include <kern/clock.h>
#include <mach/kern_return.h>
extern semaphore_t execve_semaphore;
static int execargs_waiters = 0;
lck_mtx_t *execargs_cache_lock;
static void
execargs_lock_lock(void) {
lck_mtx_lock_spin(execargs_cache_lock);
}
static void
execargs_lock_unlock(void) {
lck_mtx_unlock(execargs_cache_lock);
}
static void
execargs_lock_sleep(void) {
lck_mtx_sleep(execargs_cache_lock, LCK_SLEEP_DEFAULT, &execargs_free_count, THREAD_UNINT);
}
static kern_return_t
execargs_purgeable_allocate(char **execarg_address) {
kern_return_t kr = vm_allocate(bsd_pageable_map, (vm_offset_t *)execarg_address, NCARGS + PAGE_SIZE, VM_FLAGS_ANYWHERE | VM_FLAGS_PURGABLE);
assert(kr == KERN_SUCCESS);
return kr;
}
static kern_return_t
execargs_purgeable_reference(void *execarg_address) {
int state = VM_PURGABLE_NONVOLATILE;
kern_return_t kr = vm_purgable_control(bsd_pageable_map, (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
assert(kr == KERN_SUCCESS);
return kr;
}
static kern_return_t
execargs_purgeable_volatilize(void *execarg_address) {
int state = VM_PURGABLE_VOLATILE | VM_PURGABLE_ORDERING_OBSOLETE;
kern_return_t kr;
kr = vm_purgable_control(bsd_pageable_map, (vm_offset_t) execarg_address, VM_PURGABLE_SET_STATE, &state);
assert(kr == KERN_SUCCESS);
return kr;
}
static void
execargs_wakeup_waiters(void) {
thread_wakeup(&execargs_free_count);
}
static int
execargs_alloc(struct image_params *imgp)
{
kern_return_t kret;
int i, cache_index = -1;
execargs_lock_lock();
while (execargs_free_count == 0) {
execargs_waiters++;
execargs_lock_sleep();
execargs_waiters--;
}
execargs_free_count--;
for (i = 0; i < execargs_cache_size; i++) {
vm_offset_t element = execargs_cache[i];
if (element) {
cache_index = i;
imgp->ip_strings = (char *)(execargs_cache[i]);
execargs_cache[i] = 0;
break;
}
}
assert(execargs_free_count >= 0);
execargs_lock_unlock();
if (cache_index == -1) {
kret = execargs_purgeable_allocate(&imgp->ip_strings);
}
else
kret = execargs_purgeable_reference(imgp->ip_strings);
assert(kret == KERN_SUCCESS);
if (kret != KERN_SUCCESS) {
return (ENOMEM);
}
imgp->ip_vdata = imgp->ip_strings + NCARGS;
return (0);
}
static int
execargs_free(struct image_params *imgp)
{
kern_return_t kret;
int i;
boolean_t needs_wakeup = FALSE;
kret = execargs_purgeable_volatilize(imgp->ip_strings);
execargs_lock_lock();
execargs_free_count++;
for (i = 0; i < execargs_cache_size; i++) {
vm_offset_t element = execargs_cache[i];
if (element == 0) {
execargs_cache[i] = (vm_offset_t) imgp->ip_strings;
imgp->ip_strings = NULL;
break;
}
}
assert(imgp->ip_strings == NULL);
if (execargs_waiters > 0)
needs_wakeup = TRUE;
execargs_lock_unlock();
if (needs_wakeup == TRUE)
execargs_wakeup_waiters();
return ((kret == KERN_SUCCESS ? 0 : EINVAL));
}
static void
exec_resettextvp(proc_t p, struct image_params *imgp)
{
vnode_t vp;
off_t offset;
vnode_t tvp = p->p_textvp;
int ret;
vp = imgp->ip_vp;
offset = imgp->ip_arch_offset;
if (vp == NULLVP)
panic("exec_resettextvp: expected valid vp");
ret = vnode_ref(vp);
proc_lock(p);
if (ret == 0) {
p->p_textvp = vp;
p->p_textoff = offset;
} else {
p->p_textvp = NULLVP;
p->p_textoff = 0;
}
proc_unlock(p);
if ( tvp != NULLVP) {
if (vnode_getwithref(tvp) == 0) {
vnode_rele(tvp);
vnode_put(tvp);
}
}
}
static int
check_for_signature(proc_t p, struct image_params *imgp)
{
mach_port_t port = NULL;
kern_return_t error = 0;
unsigned char hash[SHA1_RESULTLEN];
proc_lock(p);
p->p_csflags = imgp->ip_csflags;
proc_unlock(p);
if(p->p_csflags & (CS_HARD|CS_KILL)) {
vm_map_switch_protect(get_task_map(p->task), TRUE);
}
error = task_get_task_access_port(p->task, &port);
if (error == 0 && IPC_PORT_VALID(port) && !(p->p_csflags & CS_VALID)) {
error = find_code_signature(port, p->p_pid);
if (error == KERN_FAILURE) {
psignal(p, SIGKILL);
return EACCES;
}
if (p->p_textvp != NULLVP) {
error = ubc_cs_getcdhash(p->p_textvp, p->p_textoff, hash);
if (error == 0) {
proc_lock(p);
p->p_csflags |= CS_VALID;
proc_unlock(p);
}
}
}
return KERN_SUCCESS;
}