+ break;
+#if CONFIG_CODE_DECRYPTION
+ case LC_ENCRYPTION_INFO:
+ case LC_ENCRYPTION_INFO_64:
+ if (pass != 3) {
+ break;
+ }
+ ret = set_code_unprotect(
+ (struct encryption_info_command *) lcp,
+ addr, map, slide, vp, file_offset,
+ header->cputype, header->cpusubtype);
+ if (ret != LOAD_SUCCESS) {
+ os_reason_t load_failure_reason = OS_REASON_NULL;
+ printf("proc %d: set_code_unprotect() error %d "
+ "for file \"%s\"\n",
+ p->p_pid, ret, vp->v_name);
+ /*
+ * Don't let the app run if it's
+ * encrypted but we failed to set up the
+ * decrypter. If the keys are missing it will
+ * return LOAD_DECRYPTFAIL.
+ */
+ if (ret == LOAD_DECRYPTFAIL) {
+ /* failed to load due to missing FP keys */
+ proc_lock(p);
+ p->p_lflag |= P_LTERM_DECRYPTFAIL;
+ proc_unlock(p);
+
+ KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+ p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_FAIRPLAY_DECRYPT, 0, 0);
+ load_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_FAIRPLAY_DECRYPT);
+ } else {
+ KERNEL_DEBUG_CONSTANT(BSDDBG_CODE(DBG_BSD_PROC, BSD_PROC_EXITREASON_CREATE) | DBG_FUNC_NONE,
+ p->p_pid, OS_REASON_EXEC, EXEC_EXIT_REASON_DECRYPT, 0, 0);
+ load_failure_reason = os_reason_create(OS_REASON_EXEC, EXEC_EXIT_REASON_DECRYPT);
+ }
+
+ /*
+ * Don't signal the process if it was forked and in a partially constructed
+ * state as part of a spawn -- it will just be torn down when the exec fails.
+ */
+ if (!spawn) {
+ assert(load_failure_reason != OS_REASON_NULL);
+ if (vfexec) {
+ psignal_vfork_with_reason(p, get_threadtask(imgp->ip_new_thread), imgp->ip_new_thread, SIGKILL, load_failure_reason);
+ load_failure_reason = OS_REASON_NULL;
+ } else {
+ psignal_with_reason(p, SIGKILL, load_failure_reason);
+ load_failure_reason = OS_REASON_NULL;
+ }
+ } else {
+ os_reason_free(load_failure_reason);
+ load_failure_reason = OS_REASON_NULL;
+ }
+ }
+ break;
+#endif
+ case LC_VERSION_MIN_IPHONEOS:
+ case LC_VERSION_MIN_MACOSX:
+ case LC_VERSION_MIN_WATCHOS:
+ case LC_VERSION_MIN_TVOS: {
+ struct version_min_command *vmc;
+
+ if (depth != 1 || pass != 0) {
+ break;
+ }
+ vmc = (struct version_min_command *) lcp;
+ ret = load_version(vmc, &found_version_cmd, imgp->ip_flags, result);
+#if XNU_TARGET_OS_OSX
+ if (ret == LOAD_SUCCESS) {
+ if (result->ip_platform == PLATFORM_IOS) {
+ vm_map_mark_alien(map);
+ } else {
+ assert(!vm_map_is_alien(map));
+ }
+ }
+#endif /* XNU_TARGET_OS_OSX */
+ break;
+ }
+ case LC_BUILD_VERSION: {
+ if (depth != 1 || pass != 0) {
+ break;
+ }
+ struct build_version_command* bvc = (struct build_version_command*)lcp;
+ if (bvc->cmdsize < sizeof(*bvc)) {
+ ret = LOAD_BADMACHO;
+ break;
+ }
+ if (found_version_cmd == TRUE) {
+ ret = LOAD_BADMACHO;
+ break;
+ }
+ result->ip_platform = bvc->platform;
+ result->lr_sdk = bvc->sdk;
+ result->lr_min_sdk = bvc->minos;
+ found_version_cmd = TRUE;
+#if XNU_TARGET_OS_OSX
+ if (result->ip_platform == PLATFORM_IOS) {
+ vm_map_mark_alien(map);
+ } else {
+ assert(!vm_map_is_alien(map));
+ }
+#endif /* XNU_TARGET_OS_OSX */
+ break;
+ }
+ default:
+ /* Other commands are ignored by the kernel */
+ ret = LOAD_SUCCESS;
+ break;
+ }
+ if (ret != LOAD_SUCCESS) {
+ break;
+ }
+ }
+ if (ret != LOAD_SUCCESS) {
+ break;
+ }
+ }
+
+ if (ret == LOAD_SUCCESS) {
+ if (!got_code_signatures && cs_process_global_enforcement()) {
+ ret = LOAD_FAILURE;
+ }
+
+ /* Make sure if we need dyld, we got it */
+ if (result->needs_dynlinker && !dlp) {
+ ret = LOAD_FAILURE;
+ }
+
+ if ((ret == LOAD_SUCCESS) && (dlp != 0)) {
+ /*
+ * load the dylinker, and slide it by the independent DYLD ASLR
+ * offset regardless of the PIE-ness of the main binary.
+ */
+ ret = load_dylinker(dlp, header->cputype, map, thread, depth,
+ dyld_aslr_offset, result, imgp);
+ }
+
+
+ if ((ret == LOAD_SUCCESS) && (depth == 1)) {
+ if (result->thread_count == 0) {
+ ret = LOAD_FAILURE;
+ }
+#if CONFIG_ENFORCE_SIGNED_CODE
+ if (result->needs_dynlinker && !(result->csflags & CS_DYLD_PLATFORM)) {
+ ret = LOAD_FAILURE;
+ }
+#endif
+ }
+ }
+
+ if (ret == LOAD_BADMACHO && found_xhdr) {
+ ret = LOAD_BADMACHO_UPX;
+ }
+
+ kfree(addr, alloc_size);
+
+ return ret;
+}
+
+load_return_t
+validate_potential_simulator_binary(
+ cpu_type_t exectype __unused,
+ struct image_params *imgp __unused,
+ off_t file_offset __unused,
+ off_t macho_size __unused)
+{
+#if __x86_64__
+ /* Allow 32 bit exec only for simulator binaries */
+ if (bootarg_no32exec && imgp != NULL && exectype == CPU_TYPE_X86) {
+ if (imgp->ip_simulator_binary == IMGPF_SB_DEFAULT) {
+ boolean_t simulator_binary = check_if_simulator_binary(imgp, file_offset, macho_size);
+ imgp->ip_simulator_binary = simulator_binary ? IMGPF_SB_TRUE : IMGPF_SB_FALSE;
+ }
+
+ if (imgp->ip_simulator_binary != IMGPF_SB_TRUE) {
+ return LOAD_BADARCH;
+ }
+ }
+#endif
+ return LOAD_SUCCESS;
+}
+
+#if __x86_64__
+static boolean_t
+check_if_simulator_binary(
+ struct image_params *imgp,
+ off_t file_offset,
+ off_t macho_size)
+{
+ struct mach_header *header;
+ char *ip_vdata = NULL;
+ kauth_cred_t cred = NULL;
+ uint32_t ncmds;
+ struct load_command *lcp;
+ boolean_t simulator_binary = FALSE;
+ void * addr = NULL;
+ vm_size_t alloc_size, cmds_size;
+ size_t offset;
+ proc_t p = current_proc(); /* XXXX */
+ int error;
+ int resid = 0;
+ size_t mach_header_sz = sizeof(struct mach_header);
+
+
+ cred = kauth_cred_proc_ref(p);
+
+ /* Allocate page to copyin mach header */
+ ip_vdata = kalloc(PAGE_SIZE);
+ bzero(ip_vdata, PAGE_SIZE);
+ if (ip_vdata == NULL) {
+ goto bad;
+ }
+
+ /* Read the Mach-O header */
+ error = vn_rdwr(UIO_READ, imgp->ip_vp, ip_vdata,
+ PAGE_SIZE, file_offset,
+ UIO_SYSSPACE, (IO_UNIT | IO_NODELOCKED),
+ cred, &resid, p);
+ if (error) {
+ goto bad;
+ }
+
+ header = (struct mach_header *)ip_vdata;
+
+ if (header->magic == MH_MAGIC_64 ||
+ header->magic == MH_CIGAM_64) {
+ mach_header_sz = sizeof(struct mach_header_64);
+ }
+
+ /* ensure header + sizeofcmds falls within the file */
+ if (os_add_overflow(mach_header_sz, header->sizeofcmds, &cmds_size) ||
+ (off_t)cmds_size > macho_size ||
+ round_page_overflow(cmds_size, &alloc_size) ||
+ alloc_size > INT_MAX) {
+ goto bad;
+ }
+
+ /*
+ * Map the load commands into kernel memory.
+ */
+ addr = kalloc(alloc_size);
+ if (addr == NULL) {
+ goto bad;
+ }
+
+ error = vn_rdwr(UIO_READ, imgp->ip_vp, addr, (int)alloc_size, file_offset,
+ UIO_SYSSPACE, IO_NODELOCKED, cred, &resid, p);
+ if (error) {
+ goto bad;
+ }
+
+ if (resid) {
+ /* We must be able to read in as much as the mach_header indicated */
+ goto bad;
+ }
+
+ /*
+ * Loop through each of the load_commands indicated by the
+ * Mach-O header; if an absurd value is provided, we just
+ * run off the end of the reserved section by incrementing
+ * the offset too far, so we are implicitly fail-safe.
+ */
+ offset = mach_header_sz;
+ ncmds = header->ncmds;
+
+ while (ncmds--) {
+ /* ensure enough space for a minimal load command */
+ if (offset + sizeof(struct load_command) > cmds_size) {
+ break;
+ }
+
+ /*
+ * Get a pointer to the command.
+ */
+ lcp = (struct load_command *)(addr + offset);
+
+ /*
+ * Perform prevalidation of the struct load_command
+ * before we attempt to use its contents. Invalid
+ * values are ones which result in an overflow, or
+ * which can not possibly be valid commands, or which
+ * straddle or exist past the reserved section at the
+ * start of the image.
+ */
+ if (os_add_overflow(offset, lcp->cmdsize, &offset) ||
+ lcp->cmdsize < sizeof(struct load_command) ||
+ offset > cmds_size) {
+ break;
+ }
+
+ /* Check if its a simulator binary. */
+ switch (lcp->cmd) {
+ case LC_VERSION_MIN_WATCHOS:
+ simulator_binary = TRUE;
+ break;
+
+ case LC_BUILD_VERSION: {
+ struct build_version_command *bvc;
+
+ bvc = (struct build_version_command *) lcp;
+ if (bvc->cmdsize < sizeof(*bvc)) {
+ /* unsafe to use this command struct if cmdsize
+ * validated above is too small for it to fit */
+ break;
+ }
+ if (bvc->platform == PLATFORM_IOSSIMULATOR ||
+ bvc->platform == PLATFORM_WATCHOSSIMULATOR) {
+ simulator_binary = TRUE;
+ }
+
+ break;
+ }
+
+ case LC_VERSION_MIN_IPHONEOS: {
+ simulator_binary = TRUE;
+ break;
+ }
+
+ default:
+ /* ignore other load commands */
+ break;
+ }
+
+ if (simulator_binary == TRUE) {
+ break;
+ }
+ }
+
+bad:
+ if (ip_vdata) {
+ kfree(ip_vdata, PAGE_SIZE);
+ }
+
+ if (cred) {
+ kauth_cred_unref(&cred);
+ }
+
+ if (addr) {
+ kfree(addr, alloc_size);
+ }
+
+ return simulator_binary;
+}
+#endif /* __x86_64__ */
+
+#if CONFIG_CODE_DECRYPTION
+
+#define APPLE_UNPROTECTED_HEADER_SIZE (3 * 4096)
+
+static load_return_t
+unprotect_dsmos_segment(
+ uint64_t file_off,
+ uint64_t file_size,
+ struct vnode *vp,
+ off_t macho_offset,
+ vm_map_t map,
+ vm_map_offset_t map_addr,
+ vm_map_size_t map_size)
+{
+ kern_return_t kr;
+ uint64_t slice_off;
+
+ /*
+ * The first APPLE_UNPROTECTED_HEADER_SIZE bytes (from offset 0 of
+ * this part of a Universal binary) are not protected...
+ * The rest needs to be "transformed".
+ */
+ slice_off = file_off - macho_offset;
+ if (slice_off <= APPLE_UNPROTECTED_HEADER_SIZE &&
+ slice_off + file_size <= APPLE_UNPROTECTED_HEADER_SIZE) {
+ /* it's all unprotected, nothing to do... */
+ kr = KERN_SUCCESS;
+ } else {
+ if (slice_off <= APPLE_UNPROTECTED_HEADER_SIZE) {
+ /*
+ * We start mapping in the unprotected area.
+ * Skip the unprotected part...
+ */
+ uint64_t delta_file;
+ vm_map_offset_t delta_map;
+
+ delta_file = (uint64_t)APPLE_UNPROTECTED_HEADER_SIZE;
+ delta_file -= slice_off;
+ if (os_convert_overflow(delta_file, &delta_map)) {
+ return LOAD_BADMACHO;
+ }
+ if (os_add_overflow(map_addr, delta_map, &map_addr)) {
+ return LOAD_BADMACHO;
+ }
+ if (os_sub_overflow(map_size, delta_map, &map_size)) {
+ return LOAD_BADMACHO;
+ }
+ }
+ /* ... transform the rest of the mapping. */
+ struct pager_crypt_info crypt_info;
+ crypt_info.page_decrypt = dsmos_page_transform;
+ crypt_info.crypt_ops = NULL;
+ crypt_info.crypt_end = NULL;
+#pragma unused(vp, macho_offset)
+ crypt_info.crypt_ops = (void *)0x2e69cf40;
+ vm_map_offset_t crypto_backing_offset;
+ crypto_backing_offset = -1; /* i.e. use map entry's offset */
+#if VM_MAP_DEBUG_APPLE_PROTECT
+ if (vm_map_debug_apple_protect) {
+ struct proc *p;
+ p = current_proc();
+ printf("APPLE_PROTECT: %d[%s] map %p "
+ "[0x%llx:0x%llx] %s(%s)\n",
+ p->p_pid, p->p_comm, map,
+ (uint64_t) map_addr,
+ (uint64_t) (map_addr + map_size),
+ __FUNCTION__, vp->v_name);
+ }
+#endif /* VM_MAP_DEBUG_APPLE_PROTECT */
+
+ /* The DSMOS pager can only be used by apple signed code */
+ struct cs_blob * blob = csvnode_get_blob(vp, file_off);
+ if (blob == NULL || !blob->csb_platform_binary || blob->csb_platform_path) {
+ return LOAD_FAILURE;
+ }
+
+ kr = vm_map_apple_protected(map,
+ map_addr,
+ map_addr + map_size,
+ crypto_backing_offset,
+ &crypt_info,
+ CRYPTID_APP_ENCRYPTION);
+ }
+
+ if (kr != KERN_SUCCESS) {
+ return LOAD_FAILURE;
+ }
+ return LOAD_SUCCESS;
+}
+#else /* CONFIG_CODE_DECRYPTION */
+static load_return_t
+unprotect_dsmos_segment(
+ __unused uint64_t file_off,
+ __unused uint64_t file_size,
+ __unused struct vnode *vp,
+ __unused off_t macho_offset,
+ __unused vm_map_t map,
+ __unused vm_map_offset_t map_addr,
+ __unused vm_map_size_t map_size)
+{
+ return LOAD_SUCCESS;
+}
+#endif /* CONFIG_CODE_DECRYPTION */
+
+
+/*
+ * map_segment:
+ * Maps a Mach-O segment, taking care of mis-alignment (wrt the system
+ * page size) issues.
+ *
+ * The mapping might result in 1, 2 or 3 map entries:
+ * 1. for the first page, which could be overlap with the previous
+ * mapping,
+ * 2. for the center (if applicable),
+ * 3. for the last page, which could overlap with the next mapping.
+ *
+ * For each of those map entries, we might have to interpose a
+ * "fourk_pager" to deal with mis-alignment wrt the system page size,
+ * either in the mapping address and/or size or the file offset and/or
+ * size.
+ * The "fourk_pager" itself would be mapped with proper alignment
+ * wrt the system page size and would then be populated with the
+ * information about the intended mapping, with a "4KB" granularity.
+ */
+static kern_return_t
+map_segment(
+ vm_map_t map,
+ vm_map_offset_t vm_start,
+ vm_map_offset_t vm_end,
+ memory_object_control_t control,
+ vm_map_offset_t file_start,
+ vm_map_offset_t file_end,
+ vm_prot_t initprot,
+ vm_prot_t maxprot,
+ load_result_t *result)
+{
+ vm_map_offset_t cur_offset, cur_start, cur_end;
+ kern_return_t ret;
+ vm_map_offset_t effective_page_mask;
+ vm_map_kernel_flags_t vmk_flags, cur_vmk_flags;
+
+ if (vm_end < vm_start ||
+ file_end < file_start) {
+ return LOAD_BADMACHO;
+ }
+ if (vm_end == vm_start ||
+ file_end == file_start) {
+ /* nothing to map... */
+ return LOAD_SUCCESS;
+ }
+
+ effective_page_mask = vm_map_page_mask(map);
+
+ vmk_flags = VM_MAP_KERNEL_FLAGS_NONE;
+ if (vm_map_page_aligned(vm_start, effective_page_mask) &&
+ vm_map_page_aligned(vm_end, effective_page_mask) &&
+ vm_map_page_aligned(file_start, effective_page_mask) &&
+ vm_map_page_aligned(file_end, effective_page_mask)) {
+ /* all page-aligned and map-aligned: proceed */
+ } else {
+#if __arm64__
+ /* use an intermediate "4K" pager */
+ vmk_flags.vmkf_fourk = TRUE;
+#else /* __arm64__ */
+ panic("map_segment: unexpected mis-alignment "
+ "vm[0x%llx:0x%llx] file[0x%llx:0x%llx]\n",
+ (uint64_t) vm_start,
+ (uint64_t) vm_end,
+ (uint64_t) file_start,
+ (uint64_t) file_end);
+#endif /* __arm64__ */
+ }
+
+ cur_offset = 0;
+ cur_start = vm_start;
+ cur_end = vm_start;
+#if __arm64__
+ if (!vm_map_page_aligned(vm_start, effective_page_mask)) {
+ /* one 4K pager for the 1st page */
+ cur_end = vm_map_round_page(cur_start, effective_page_mask);
+ if (cur_end > vm_end) {
+ cur_end = vm_start + (file_end - file_start);
+ }
+ if (control != MEMORY_OBJECT_CONTROL_NULL) {
+ /* no copy-on-read for mapped binaries */
+ vmk_flags.vmkf_no_copy_on_read = 1;
+ ret = vm_map_enter_mem_object_control(
+ map,
+ &cur_start,
+ cur_end - cur_start,
+ (mach_vm_offset_t)0,
+ VM_FLAGS_FIXED,
+ vmk_flags,
+ VM_KERN_MEMORY_NONE,
+ control,
+ file_start + cur_offset,
+ TRUE, /* copy */
+ initprot, maxprot,
+ VM_INHERIT_DEFAULT);
+ } else {
+ ret = vm_map_enter_mem_object(
+ map,
+ &cur_start,
+ cur_end - cur_start,
+ (mach_vm_offset_t)0,
+ VM_FLAGS_FIXED,
+ vmk_flags,
+ VM_KERN_MEMORY_NONE,
+ IPC_PORT_NULL,
+ 0, /* offset */
+ TRUE, /* copy */
+ initprot, maxprot,
+ VM_INHERIT_DEFAULT);
+ }
+ if (ret != KERN_SUCCESS) {
+ return LOAD_NOSPACE;
+ }
+ cur_offset += cur_end - cur_start;
+ }
+#endif /* __arm64__ */
+ if (cur_end >= vm_start + (file_end - file_start)) {
+ /* all mapped: done */
+ goto done;
+ }
+ if (vm_map_round_page(cur_end, effective_page_mask) >=
+ vm_map_trunc_page(vm_start + (file_end - file_start),
+ effective_page_mask)) {
+ /* no middle */
+ } else {
+ cur_start = cur_end;
+ if ((vm_start & effective_page_mask) !=
+ (file_start & effective_page_mask)) {
+ /* one 4K pager for the middle */
+ cur_vmk_flags = vmk_flags;
+ } else {
+ /* regular mapping for the middle */
+ cur_vmk_flags = VM_MAP_KERNEL_FLAGS_NONE;
+ }
+
+#if !defined(XNU_TARGET_OS_OSX)
+ (void) result;
+#else /* !defined(XNU_TARGET_OS_OSX) */
+ /*
+ * This process doesn't have its new csflags (from
+ * the image being loaded) yet, so tell VM to override the
+ * current process's CS_ENFORCEMENT for this mapping.
+ */
+ if (result->csflags & CS_ENFORCEMENT) {
+ cur_vmk_flags.vmkf_cs_enforcement = TRUE;
+ } else {
+ cur_vmk_flags.vmkf_cs_enforcement = FALSE;
+ }
+ cur_vmk_flags.vmkf_cs_enforcement_override = TRUE;
+#endif /* !defined(XNU_TARGET_OS_OSX) */
+
+ if (result->is_cambria && (initprot & VM_PROT_EXECUTE) == VM_PROT_EXECUTE) {
+ cur_vmk_flags.vmkf_translated_allow_execute = TRUE;
+ }
+
+ cur_end = vm_map_trunc_page(vm_start + (file_end -
+ file_start),
+ effective_page_mask);
+ if (control != MEMORY_OBJECT_CONTROL_NULL) {
+ /* no copy-on-read for mapped binaries */
+ cur_vmk_flags.vmkf_no_copy_on_read = 1;
+ ret = vm_map_enter_mem_object_control(
+ map,
+ &cur_start,
+ cur_end - cur_start,
+ (mach_vm_offset_t)0,
+ VM_FLAGS_FIXED,
+ cur_vmk_flags,
+ VM_KERN_MEMORY_NONE,
+ control,
+ file_start + cur_offset,
+ TRUE, /* copy */
+ initprot, maxprot,
+ VM_INHERIT_DEFAULT);
+ } else {
+ ret = vm_map_enter_mem_object(
+ map,
+ &cur_start,
+ cur_end - cur_start,
+ (mach_vm_offset_t)0,
+ VM_FLAGS_FIXED,
+ cur_vmk_flags,
+ VM_KERN_MEMORY_NONE,
+ IPC_PORT_NULL,
+ 0, /* offset */
+ TRUE, /* copy */
+ initprot, maxprot,
+ VM_INHERIT_DEFAULT);
+ }
+ if (ret != KERN_SUCCESS) {
+ return LOAD_NOSPACE;
+ }
+ cur_offset += cur_end - cur_start;
+ }
+ if (cur_end >= vm_start + (file_end - file_start)) {
+ /* all mapped: done */
+ goto done;
+ }
+ cur_start = cur_end;
+#if __arm64__
+ if (!vm_map_page_aligned(vm_start + (file_end - file_start),
+ effective_page_mask)) {
+ /* one 4K pager for the last page */
+ cur_end = vm_start + (file_end - file_start);
+ if (control != MEMORY_OBJECT_CONTROL_NULL) {
+ /* no copy-on-read for mapped binaries */
+ vmk_flags.vmkf_no_copy_on_read = 1;
+ ret = vm_map_enter_mem_object_control(
+ map,
+ &cur_start,
+ cur_end - cur_start,
+ (mach_vm_offset_t)0,
+ VM_FLAGS_FIXED,
+ vmk_flags,
+ VM_KERN_MEMORY_NONE,
+ control,
+ file_start + cur_offset,
+ TRUE, /* copy */
+ initprot, maxprot,
+ VM_INHERIT_DEFAULT);
+ } else {
+ ret = vm_map_enter_mem_object(
+ map,
+ &cur_start,
+ cur_end - cur_start,
+ (mach_vm_offset_t)0,
+ VM_FLAGS_FIXED,
+ vmk_flags,
+ VM_KERN_MEMORY_NONE,
+ IPC_PORT_NULL,
+ 0, /* offset */
+ TRUE, /* copy */
+ initprot, maxprot,
+ VM_INHERIT_DEFAULT);
+ }
+ if (ret != KERN_SUCCESS) {
+ return LOAD_NOSPACE;
+ }
+ cur_offset += cur_end - cur_start;
+ }
+#endif /* __arm64__ */
+done:
+ assert(cur_end >= vm_start + (file_end - file_start));
+ return LOAD_SUCCESS;
+}
+
+static
projects / apple / xnu.git / blobdiff