X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/d7e50217d7adf6e52786a38bcaa4cd698cb9a79e..316670eb35587141e969394ae8537d66b9211e80:/bsd/kern/mach_loader.c?ds=sidebyside diff --git a/bsd/kern/mach_loader.c b/bsd/kern/mach_loader.c index 7de9bed8c..02b660be1 100644 --- a/bsd/kern/mach_loader.c +++ b/bsd/kern/mach_loader.c @@ -1,16 +1,19 @@ /* - * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved. + * Copyright (c) 2000-2010 Apple Inc. All rights reserved. * - * @APPLE_LICENSE_HEADER_START@ - * - * Copyright (c) 1999-2003 Apple Computer, 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. Please obtain a copy of the License at - * http://www.opensource.apple.com/apsl/ and read it before using this - * file. + * 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 @@ -20,7 +23,7 @@ * Please see the License for the specific language governing rights and * limitations under the License. * - * @APPLE_LICENSE_HEADER_END@ + * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* * Copyright (C) 1988, 1989, NeXT, Inc. @@ -33,152 +36,329 @@ * 21-Jul-88 Avadis Tevanian, Jr. (avie) at NeXT * Started. */ + #include -#include +#include #include #include -#include +#include +#include #include #include -#include +#include #include -#include +#include +#include #include +#include /* vm_allocate() */ +#include /* mach_vm_allocate() */ +#include +#include +#include +#include +#include +#include + +#include +#include #include +#include +#include +#include +#include +#include #include #include -#include - +#include #include #include #include #include -#include - -#include -#include +#include -#include +/* + * XXX vm/pmap.h should not treat these prototypes as MACH_KERNEL_PRIVATE + * when KERNEL is defined. + */ +extern pmap_t pmap_create(ledger_t ledger, vm_map_size_t size, + boolean_t is_64bit); + +/* XXX should have prototypes in a shared header file */ +extern int get_map_nentries(vm_map_t); + +extern kern_return_t memory_object_signed(memory_object_control_t control, + boolean_t is_signed); + +/* An empty load_result_t */ +static load_result_t load_result_null = { + .mach_header = MACH_VM_MIN_ADDRESS, + .entry_point = MACH_VM_MIN_ADDRESS, + .user_stack = MACH_VM_MIN_ADDRESS, + .user_stack_size = 0, + .all_image_info_addr = MACH_VM_MIN_ADDRESS, + .all_image_info_size = 0, + .thread_count = 0, + .unixproc = 0, + .dynlinker = 0, + .needs_dynlinker = 0, + .prog_allocated_stack = 0, + .prog_stack_size = 0, + .validentry = 0, + .csflags = 0, + .uuid = { 0 }, + .min_vm_addr = MACH_VM_MAX_ADDRESS, + .max_vm_addr = MACH_VM_MIN_ADDRESS +}; /* * Prototypes of static functions. */ -static -load_return_t +static load_return_t parse_machfile( struct vnode *vp, - vm_map_t map, - thread_act_t thr_act, + vm_map_t map, + thread_t thread, struct mach_header *header, - unsigned long file_offset, - unsigned long macho_size, - int depth, - load_result_t *result, - boolean_t clean_regions -), + off_t file_offset, + off_t macho_size, + int depth, + int64_t slide, + load_result_t *result +); + +static load_return_t load_segment( - struct segment_command *scp, - void * pager, - unsigned long pager_offset, - unsigned long macho_size, - unsigned long end_of_file, - vm_map_t map, + struct load_command *lcp, + uint32_t filetype, + void *control, + off_t pager_offset, + off_t macho_size, + struct vnode *vp, + vm_map_t map, + int64_t slide, load_result_t *result -), +); + +static load_return_t +load_code_signature( + struct linkedit_data_command *lcp, + struct vnode *vp, + off_t macho_offset, + off_t macho_size, + cpu_type_t cputype, + load_result_t *result); + +#if CONFIG_CODE_DECRYPTION +static load_return_t +set_code_unprotect( + struct encryption_info_command *lcp, + caddr_t addr, + vm_map_t map, + int64_t slide, + struct vnode *vp); +#endif + +static +load_return_t +load_main( + struct entry_point_command *epc, + thread_t thread, + int64_t slide, + load_result_t *result +); + +static load_return_t load_unixthread( struct thread_command *tcp, - thread_act_t thr_act, - load_result_t *result -), -load_thread( - struct thread_command *tcp, - thread_act_t thr_act, + thread_t thread, + int64_t slide, load_result_t *result -), +); + +static load_return_t load_threadstate( thread_t thread, - unsigned long *ts, - unsigned long total_size -), + uint32_t *ts, + uint32_t total_size +); + +static load_return_t load_threadstack( thread_t thread, - unsigned long *ts, - unsigned long total_size, - vm_offset_t *user_stack, + uint32_t *ts, + uint32_t total_size, + mach_vm_offset_t *user_stack, int *customstack -), +); + +static load_return_t load_threadentry( thread_t thread, - unsigned long *ts, - unsigned long total_size, - vm_offset_t *entry_point -), + uint32_t *ts, + uint32_t total_size, + mach_vm_offset_t *entry_point +); + +static load_return_t load_dylinker( struct dylinker_command *lcp, + integer_t archbits, vm_map_t map, - thread_act_t thr_act, + thread_t thread, int depth, - load_result_t *result, - boolean_t clean_regions -), + int64_t slide, + load_result_t *result +); + +struct macho_data; + +static load_return_t get_macho_vnode( char *path, + integer_t archbits, struct mach_header *mach_header, - unsigned long *file_offset, - unsigned long *macho_size, + off_t *file_offset, + off_t *macho_size, + struct macho_data *macho_data, struct vnode **vpp ); +static inline void +widen_segment_command(const struct segment_command *scp32, + struct segment_command_64 *scp) +{ + scp->cmd = scp32->cmd; + scp->cmdsize = scp32->cmdsize; + bcopy(scp32->segname, scp->segname, sizeof(scp->segname)); + scp->vmaddr = scp32->vmaddr; + scp->vmsize = scp32->vmsize; + scp->fileoff = scp32->fileoff; + scp->filesize = scp32->filesize; + scp->maxprot = scp32->maxprot; + scp->initprot = scp32->initprot; + scp->nsects = scp32->nsects; + scp->flags = scp32->flags; +} + +static void +note_all_image_info_section(const struct segment_command_64 *scp, + boolean_t is64, size_t section_size, const void *sections, + int64_t slide, load_result_t *result) +{ + const union { + struct section s32; + struct section_64 s64; + } *sectionp; + unsigned int i; + + if (strncmp(scp->segname, "__DATA", sizeof(scp->segname)) != 0) + return; + for (i = 0; i < scp->nsects; ++i) { + sectionp = (const void *) + ((const char *)sections + section_size * i); + if (0 == strncmp(sectionp->s64.sectname, "__all_image_info", + sizeof(sectionp->s64.sectname))) { + result->all_image_info_addr = + is64 ? sectionp->s64.addr : sectionp->s32.addr; + result->all_image_info_addr += slide; + result->all_image_info_size = + is64 ? sectionp->s64.size : sectionp->s32.size; + return; + } + } +} + load_return_t load_machfile( - struct vnode *vp, + struct image_params *imgp, struct mach_header *header, - unsigned long file_offset, - unsigned long macho_size, - load_result_t *result, - thread_act_t thr_act, + thread_t thread, vm_map_t new_map, - boolean_t clean_regions + load_result_t *result ) { - pmap_t pmap; + struct vnode *vp = imgp->ip_vp; + off_t file_offset = imgp->ip_arch_offset; + off_t macho_size = imgp->ip_arch_size; + off_t file_size = imgp->ip_vattr->va_data_size; + + pmap_t pmap = 0; /* protected by create_map */ vm_map_t map; vm_map_t old_map; + task_t old_task = TASK_NULL; /* protected by create_map */ load_result_t myresult; - kern_return_t kret; load_return_t lret; - boolean_t create_map = TRUE; + boolean_t create_map = FALSE; + int spawn = (imgp->ip_flags & IMGPF_SPAWN); + task_t task = current_task(); + proc_t p = current_proc(); + mach_vm_offset_t aslr_offset = 0; + kern_return_t kret; + + if (macho_size > file_size) { + return(LOAD_BADMACHO); + } - if (new_map != VM_MAP_NULL) { - create_map = FALSE; + if (new_map == VM_MAP_NULL) { + create_map = TRUE; + old_task = current_task(); + } + + /* + * If we are spawning, we have created backing objects for the process + * already, which include non-lazily creating the task map. So we + * are going to switch out the task map with one appropriate for the + * bitness of the image being loaded. + */ + if (spawn) { + create_map = TRUE; + old_task = get_threadtask(thread); } if (create_map) { - old_map = current_map(); -#ifdef i386 - pmap = get_task_pmap(current_task()); - pmap_reference(pmap); -#else - pmap = pmap_create((vm_size_t) 0); -#endif + pmap = pmap_create(get_task_ledger(task), (vm_map_size_t) 0, + (imgp->ip_flags & IMGPF_IS_64BIT)); + pal_switch_pmap(thread, pmap, imgp->ip_flags & IMGPF_IS_64BIT); map = vm_map_create(pmap, - get_map_min(old_map), - get_map_max(old_map), - TRUE); /**** FIXME ****/ + 0, + vm_compute_max_offset((imgp->ip_flags & IMGPF_IS_64BIT)), + TRUE); + } else map = new_map; - + +#ifndef CONFIG_ENFORCE_SIGNED_CODE + /* This turns off faulting for executable pages, which allows to + * circumvent Code Signing Enforcement */ + if ( (header->flags & MH_ALLOW_STACK_EXECUTION) ) + vm_map_disable_NX(map); +#endif + + /* Forcibly disallow execution from data pages on even if the arch + * normally permits it. */ + if ((header->flags & MH_NO_HEAP_EXECUTION) && !(imgp->ip_flags & IMGPF_ALLOW_DATA_EXEC)) + vm_map_disallow_data_exec(map); + + /* + * Compute a random offset for ASLR. + */ + if (!(imgp->ip_flags & IMGPF_DISABLE_ASLR)) { + aslr_offset = random(); + aslr_offset %= 1 << ((imgp->ip_flags & IMGPF_IS_64BIT) ? 16 : 8); + aslr_offset <<= PAGE_SHIFT; + } + if (!result) result = &myresult; - *result = (load_result_t) { 0 }; + *result = load_result_null; - lret = parse_machfile(vp, map, thr_act, header, file_offset, macho_size, - 0, result, clean_regions); + lret = parse_machfile(vp, map, thread, header, file_offset, macho_size, + 0, (int64_t)aslr_offset, result); if (lret != LOAD_SUCCESS) { if (create_map) { @@ -187,101 +367,172 @@ load_machfile( return(lret); } +#if CONFIG_EMBEDDED /* - * Commit to new map. First make sure that the current - * users of the task get done with it, and that we clean - * up the old contents of IPC and memory. The task is - * guaranteed to be single threaded upon return (us). + * Check to see if the page zero is enforced by the map->min_offset. + */ + if (vm_map_has_hard_pagezero(map, 0x1000) == FALSE) { + if (create_map) { + vm_map_deallocate(map); /* will lose pmap reference too */ + } + printf("Cannot enforce a hard page-zero for %s\n", imgp->ip_strings); + psignal(vfs_context_proc(imgp->ip_vfs_context), SIGKILL); + return (LOAD_BADMACHO); + } +#else + /* + * For 64-bit users, check for presence of a 4GB page zero + * which will enable the kernel to share the user's address space + * and hence avoid TLB flushes on kernel entry/exit + */ + + if ((imgp->ip_flags & IMGPF_IS_64BIT) && + vm_map_has_4GB_pagezero(map)) { + vm_map_set_4GB_pagezero(map); + } +#endif + /* + * Commit to new map. * - * Swap the new map for the old at the task level and at - * our activation. The latter consumes our new map reference - * but each leaves us responsible for the old_map reference. + * Swap the new map for the old, which consumes our new map + * reference but each leaves us responsible for the old_map reference. * That lets us get off the pmap associated with it, and * then we can release it. */ - if (create_map) { - task_halt(current_task()); - old_map = swap_task_map(current_task(), map); - vm_map_deallocate(old_map); - - old_map = swap_act_map(current_act(), map); - -#ifndef i386 - pmap_switch(pmap); /* Make sure we are using the new pmap */ -#endif + if (create_map) { + /* + * If this is an exec, then we are going to destroy the old + * task, and it's correct to halt it; if it's spawn, the + * task is not yet running, and it makes no sense. + */ + if (!spawn) { + /* + * Mark the task as halting and start the other + * threads towards terminating themselves. Then + * make sure any threads waiting for a process + * transition get informed that we are committed to + * this transition, and then finally complete the + * task halting (wait for threads and then cleanup + * task resources). + * + * NOTE: task_start_halt() makes sure that no new + * threads are created in the task during the transition. + * We need to mark the workqueue as exiting before we + * wait for threads to terminate (at the end of which + * we no longer have a prohibition on thread creation). + * + * Finally, clean up any lingering workqueue data structures + * that may have been left behind by the workqueue threads + * as they exited (and then clean up the work queue itself). + */ + kret = task_start_halt(task); + if (kret != KERN_SUCCESS) { + return(kret); + } + proc_transcommit(p, 0); + workqueue_mark_exiting(p); + task_complete_halt(task); + workqueue_exit(p); + } + old_map = swap_task_map(old_task, thread, map, !spawn); + vm_map_clear_4GB_pagezero(old_map); vm_map_deallocate(old_map); } return(LOAD_SUCCESS); } -int dylink_test = 1; - +/* + * The file size of a mach-o file is limited to 32 bits; this is because + * this is the limit on the kalloc() of enough bytes for a mach_header and + * the contents of its sizeofcmds, which is currently constrained to 32 + * bits in the file format itself. We read into the kernel buffer the + * commands section, and then parse it in order to parse the mach-o file + * format load_command segment(s). We are only interested in a subset of + * the total set of possible commands. If "map"==VM_MAP_NULL or + * "thread"==THREAD_NULL, do not make permament VM modifications, + * just preflight the parse. + */ static load_return_t parse_machfile( - struct vnode *vp, + struct vnode *vp, vm_map_t map, - thread_act_t thr_act, + thread_t thread, struct mach_header *header, - unsigned long file_offset, - unsigned long macho_size, + off_t file_offset, + off_t macho_size, int depth, - load_result_t *result, - boolean_t clean_regions + int64_t aslr_offset, + load_result_t *result ) { - struct machine_slot *ms; - int ncmds; - struct load_command *lcp, *next; + uint32_t ncmds; + struct load_command *lcp; struct dylinker_command *dlp = 0; - void * pager; + struct uuid_command *uulp = 0; + integer_t dlarchbits = 0; + void * control; load_return_t ret = LOAD_SUCCESS; - vm_offset_t addr, kl_addr; + caddr_t addr; + void * kl_addr; vm_size_t size,kl_size; - int offset; + size_t offset; + size_t oldoffset; /* for overflow check */ int pass; - struct proc *p = current_proc(); /* XXXX */ + proc_t p = current_proc(); /* XXXX */ int error; int resid=0; - task_t task; + size_t mach_header_sz = sizeof(struct mach_header); + boolean_t abi64; + boolean_t got_code_signatures = FALSE; + int64_t slide = 0; + + if (header->magic == MH_MAGIC_64 || + header->magic == MH_CIGAM_64) { + mach_header_sz = sizeof(struct mach_header_64); + } /* * Break infinite recursion */ - if (depth > 6) + if (depth > 6) { return(LOAD_FAILURE); - - task = (task_t)get_threadtask(thr_act); + } depth++; /* * Check to see if right machine type. */ - ms = &machine_slot[cpu_number()]; - if ((header->cputype != ms->cpu_type) || - !check_cpu_subtype(header->cpusubtype)) + if (((cpu_type_t)(header->cputype & ~CPU_ARCH_MASK) != cpu_type()) || + !grade_binary(header->cputype, + header->cpusubtype & ~CPU_SUBTYPE_MASK)) return(LOAD_BADARCH); + abi64 = ((header->cputype & CPU_ARCH_ABI64) == CPU_ARCH_ABI64); + switch (header->filetype) { case MH_OBJECT: case MH_EXECUTE: case MH_PRELOAD: - if (depth != 1) + if (depth != 1) { return (LOAD_FAILURE); + } break; case MH_FVMLIB: case MH_DYLIB: - if (depth == 1) + if (depth == 1) { return (LOAD_FAILURE); + } break; case MH_DYLINKER: - if (depth != 2) + if (depth != 2) { return (LOAD_FAILURE); + } break; default: @@ -291,20 +542,19 @@ parse_machfile( /* * Get the pager for the file. */ - UBCINFOCHECK("parse_machfile", vp); - pager = (void *) ubc_getpager(vp); + control = ubc_getobject(vp, UBC_FLAGS_NONE); /* * Map portion that must be accessible directly into * kernel's map. */ - if ((sizeof (struct mach_header) + header->sizeofcmds) > macho_size) + if ((off_t)(mach_header_sz + header->sizeofcmds) > macho_size) return(LOAD_BADMACHO); /* * Round size of Mach-O commands up to page boundry. */ - size = round_page_32(sizeof (struct mach_header) + header->sizeofcmds); + size = round_page(mach_header_sz + header->sizeofcmds); if (size <= 0) return(LOAD_BADMACHO); @@ -314,80 +564,172 @@ parse_machfile( addr = 0; kl_size = size; kl_addr = kalloc(size); - addr = kl_addr; + addr = (caddr_t)kl_addr; if (addr == NULL) return(LOAD_NOSPACE); - if(error = vn_rdwr(UIO_READ, vp, addr, size, file_offset, - UIO_SYSSPACE, 0, p->p_ucred, &resid, p)) { + error = vn_rdwr(UIO_READ, vp, addr, size, file_offset, + UIO_SYSSPACE, 0, kauth_cred_get(), &resid, p); + if (error) { if (kl_addr ) kfree(kl_addr, kl_size); - return(EIO); + return(LOAD_IOERROR); } - /* ubc_map(vp); */ /* NOT HERE */ - + + /* + * For PIE and dyld, slide everything by the ASLR offset. + */ + if ((header->flags & MH_PIE) || (header->filetype == MH_DYLINKER)) { + slide = aslr_offset; + } + /* * Scan through the commands, processing each one as necessary. */ - for (pass = 1; pass <= 2; pass++) { - offset = sizeof(struct mach_header); + for (pass = 1; pass <= 3; pass++) { + + /* + * Check that the entry point is contained in an executable segments + */ + if ((pass == 3) && (result->validentry == 0)) { + thread_state_initialize(thread); + ret = LOAD_FAILURE; + break; + } + + /* + * 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--) { /* * Get a pointer to the command. */ lcp = (struct load_command *)(addr + offset); + oldoffset = offset; offset += lcp->cmdsize; /* - * Check for valid lcp pointer by checking - * next 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 (offset > header->sizeofcmds - + sizeof(struct mach_header)) { - if (kl_addr ) - kfree(kl_addr, kl_size); - return(LOAD_BADMACHO); + if (oldoffset > offset || + lcp->cmdsize < sizeof(struct load_command) || + offset > header->sizeofcmds + mach_header_sz) { + ret = LOAD_BADMACHO; + break; } /* - * Check for valid command. + * Act on struct load_command's for which kernel + * intervention is required. */ switch(lcp->cmd) { case LC_SEGMENT: - if (pass != 1) + case LC_SEGMENT_64: + if (pass != 2) break; - ret = load_segment( - (struct segment_command *) lcp, - pager, file_offset, + ret = load_segment(lcp, + header->filetype, + control, + file_offset, macho_size, - (unsigned long)ubc_getsize(vp), + vp, map, + slide, result); break; - case LC_THREAD: - if (pass != 2) - break; - ret = load_thread((struct thread_command *)lcp, thr_act, - result); - break; case LC_UNIXTHREAD: - if (pass != 2) + if (pass != 1) break; ret = load_unixthread( - (struct thread_command *) lcp, thr_act, + (struct thread_command *) lcp, + thread, + slide, + result); + break; + case LC_MAIN: + if (pass != 1) + break; + if (depth != 1) + break; + ret = load_main( + (struct entry_point_command *) lcp, + thread, + slide, result); break; case LC_LOAD_DYLINKER: - if (pass != 2) + if (pass != 3) break; - if ((depth == 1) && (dlp == 0)) + if ((depth == 1) && (dlp == 0)) { dlp = (struct dylinker_command *)lcp; - else + dlarchbits = (header->cputype & CPU_ARCH_MASK); + } else { ret = LOAD_FAILURE; + } + break; + case LC_UUID: + if (pass == 1 && depth == 1) { + uulp = (struct uuid_command *)lcp; + memcpy(&result->uuid[0], &uulp->uuid[0], sizeof(result->uuid)); + } + break; + case LC_CODE_SIGNATURE: + /* CODE SIGNING */ + if (pass != 1) + break; + /* pager -> uip -> + load signatures & store in uip + set VM object "signed_pages" + */ + ret = load_code_signature( + (struct linkedit_data_command *) lcp, + vp, + file_offset, + macho_size, + header->cputype, + (depth == 1) ? result : NULL); + if (ret != LOAD_SUCCESS) { + printf("proc %d: load code signature error %d " + "for file \"%s\"\n", + p->p_pid, ret, vp->v_name); + ret = LOAD_SUCCESS; /* ignore error */ + } else { + got_code_signatures = TRUE; + } + break; +#if CONFIG_CODE_DECRYPTION + case LC_ENCRYPTION_INFO: + if (pass != 3) + break; + ret = set_code_unprotect( + (struct encryption_info_command *) lcp, + addr, map, slide, vp); + if (ret != LOAD_SUCCESS) { + 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 */ + psignal(p, SIGKILL); + } break; +#endif default: - ret = LOAD_SUCCESS;/* ignore other stuff */ + /* Other commands are ignored by the kernel */ + ret = LOAD_SUCCESS; + break; } if (ret != LOAD_SUCCESS) break; @@ -395,163 +737,230 @@ parse_machfile( if (ret != LOAD_SUCCESS) break; } - if ((ret == LOAD_SUCCESS) && (depth == 1)) { - vm_offset_t addr; - shared_region_mapping_t shared_region; - struct shared_region_task_mappings map_info; - shared_region_mapping_t next; - -RedoLookup: - vm_get_shared_region(task, &shared_region); - map_info.self = (vm_offset_t)shared_region; - shared_region_mapping_info(shared_region, - &(map_info.text_region), - &(map_info.text_size), - &(map_info.data_region), - &(map_info.data_size), - &(map_info.region_mappings), - &(map_info.client_base), - &(map_info.alternate_base), - &(map_info.alternate_next), - &(map_info.fs_base), - &(map_info.system), - &(map_info.flags), &next); - - if((map_info.flags & SHARED_REGION_FULL) || - (map_info.flags & SHARED_REGION_STALE)) { - shared_region_mapping_t system_region; - system_region = lookup_default_shared_region( - map_info.fs_base, map_info.system); - if((map_info.self != (vm_offset_t)system_region) && - (map_info.flags & SHARED_REGION_SYSTEM)) { - if(system_region == NULL) { - shared_file_boot_time_init( - map_info.fs_base, map_info.system); - } else { - vm_set_shared_region(task, system_region); - } - shared_region_mapping_dealloc( - (shared_region_mapping_t)map_info.self); - goto RedoLookup; - } else if (map_info.flags & SHARED_REGION_SYSTEM) { - shared_region_mapping_dealloc(system_region); - shared_file_boot_time_init( - map_info.fs_base, map_info.system); - shared_region_mapping_dealloc( - (shared_region_mapping_t)map_info.self); - } else { - shared_region_mapping_dealloc(system_region); - } + if (ret == LOAD_SUCCESS) { + if (! got_code_signatures) { + struct cs_blob *blob; + /* no embedded signatures: look for detached ones */ + blob = ubc_cs_blob_get(vp, -1, file_offset); + if (blob != NULL) { + /* get flags to be applied to the process */ + result->csflags |= blob->csb_flags; + } + } + + /* 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 always slide it by the ASLR + * offset regardless of PIE */ + ret = load_dylinker(dlp, dlarchbits, map, thread, depth, aslr_offset, result); + } - if (dylink_test) { - p->p_flag |= P_NOSHLIB; /* no shlibs in use */ - addr = map_info.client_base; - if(clean_regions) { - vm_map(map, &addr, map_info.text_size, - 0, SHARED_LIB_ALIAS, - map_info.text_region, 0, FALSE, - VM_PROT_READ, VM_PROT_READ, VM_INHERIT_SHARE); - } else { - vm_map(map, &addr, map_info.text_size, 0, - (VM_MEMORY_SHARED_PMAP << 24) - | SHARED_LIB_ALIAS, - map_info.text_region, 0, FALSE, - VM_PROT_READ, VM_PROT_READ, VM_INHERIT_SHARE); + if((ret == LOAD_SUCCESS) && (depth == 1)) { + if (result->thread_count == 0) { + ret = LOAD_FAILURE; } - addr = map_info.client_base + map_info.text_size; - vm_map(map, &addr, map_info.data_size, - 0, SHARED_LIB_ALIAS, - map_info.data_region, 0, TRUE, - VM_PROT_READ, VM_PROT_READ, VM_INHERIT_SHARE); - - while (next) { - /* this should be fleshed out for the general case */ - /* but this is not necessary for now. Indeed we */ - /* are handling the com page inside of the */ - /* shared_region mapping create calls for now for */ - /* simplicities sake. If more general support is */ - /* needed the code to manipulate the shared range */ - /* chain can be pulled out and moved to the callers*/ - shared_region_mapping_info(next, - &(map_info.text_region), - &(map_info.text_size), - &(map_info.data_region), - &(map_info.data_size), - &(map_info.region_mappings), - &(map_info.client_base), - &(map_info.alternate_base), - &(map_info.alternate_next), - &(map_info.fs_base), - &(map_info.system), - &(map_info.flags), &next); - - addr = map_info.client_base; - vm_map(map, &addr, map_info.text_size, - 0, SHARED_LIB_ALIAS, - map_info.text_region, 0, FALSE, - VM_PROT_READ, VM_PROT_READ, VM_INHERIT_SHARE); - } - } - if (dlp != 0) { - ret = load_dylinker(dlp, map, thr_act, - depth, result, clean_regions); - } + } } if (kl_addr ) kfree(kl_addr, kl_size); - if ((ret == LOAD_SUCCESS) && (depth == 1) && - (result->thread_count == 0)) - ret = LOAD_FAILURE; - if (ret == LOAD_SUCCESS) - ubc_map(vp); - return(ret); } +#if CONFIG_CODE_DECRYPTION + +#define APPLE_UNPROTECTED_HEADER_SIZE (3 * PAGE_SIZE_64) + +static load_return_t +unprotect_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; + + /* + * 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". + */ + if (file_off <= APPLE_UNPROTECTED_HEADER_SIZE && + file_off + file_size <= APPLE_UNPROTECTED_HEADER_SIZE) { + /* it's all unprotected, nothing to do... */ + kr = KERN_SUCCESS; + } else { + if (file_off <= APPLE_UNPROTECTED_HEADER_SIZE) { + /* + * We start mapping in the unprotected area. + * Skip the unprotected part... + */ + vm_map_offset_t delta; + + delta = APPLE_UNPROTECTED_HEADER_SIZE; + delta -= file_off; + map_addr += delta; + map_size -= delta; + } + /* ... 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; + kr = vm_map_apple_protected(map, + map_addr, + map_addr + map_size, + &crypt_info); + } + + if (kr != KERN_SUCCESS) { + return LOAD_FAILURE; + } + return LOAD_SUCCESS; +} +#else /* CONFIG_CODE_DECRYPTION */ +static load_return_t +unprotect_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 */ + static load_return_t load_segment( - struct segment_command *scp, - void * pager, - unsigned long pager_offset, - unsigned long macho_size, - unsigned long end_of_file, - vm_map_t map, + struct load_command *lcp, + uint32_t filetype, + void * control, + off_t pager_offset, + off_t macho_size, + struct vnode *vp, + vm_map_t map, + int64_t slide, load_result_t *result ) { + struct segment_command_64 segment_command, *scp; kern_return_t ret; - vm_offset_t map_addr, map_offset; - vm_size_t map_size, seg_size, delta_size; - caddr_t tmp; + vm_map_offset_t map_addr, map_offset; + vm_map_size_t map_size, seg_size, delta_size; vm_prot_t initprot; vm_prot_t maxprot; -#if 1 - extern int print_map_addr; -#endif /* 1 */ + size_t segment_command_size, total_section_size, + single_section_size; + boolean_t prohibit_pagezero_mapping = FALSE; + + if (LC_SEGMENT_64 == lcp->cmd) { + segment_command_size = sizeof(struct segment_command_64); + single_section_size = sizeof(struct section_64); + } else { + segment_command_size = sizeof(struct segment_command); + single_section_size = sizeof(struct section); + } + if (lcp->cmdsize < segment_command_size) + return (LOAD_BADMACHO); + total_section_size = lcp->cmdsize - segment_command_size; + + if (LC_SEGMENT_64 == lcp->cmd) + scp = (struct segment_command_64 *)lcp; + else { + scp = &segment_command; + widen_segment_command((struct segment_command *)lcp, scp); + } /* * Make sure what we get from the file is really ours (as specified * by macho_size). */ - if (scp->fileoff + scp->filesize > macho_size) + if (scp->fileoff + scp->filesize < scp->fileoff || + scp->fileoff + scp->filesize > (uint64_t)macho_size) + return (LOAD_BADMACHO); + /* + * Ensure that the number of sections specified would fit + * within the load command size. + */ + if (total_section_size / single_section_size < scp->nsects) + return (LOAD_BADMACHO); + /* + * Make sure the segment is page-aligned in the file. + */ + if ((scp->fileoff & PAGE_MASK_64) != 0) return (LOAD_BADMACHO); - - seg_size = round_page_32(scp->vmsize); - if (seg_size == 0) - return(KERN_SUCCESS); /* * Round sizes to page size. */ - map_size = round_page_32(scp->filesize); - map_addr = trunc_page_32(scp->vmaddr); + seg_size = round_page_64(scp->vmsize); + map_size = round_page_64(scp->filesize); + map_addr = trunc_page_64(scp->vmaddr); /* JVXXX note that in XNU TOT this is round instead of trunc for 64 bits */ + if (seg_size == 0) + return (KERN_SUCCESS); + if (map_addr == 0 && + map_size == 0 && + seg_size != 0 && + (scp->initprot & VM_PROT_ALL) == VM_PROT_NONE && + (scp->maxprot & VM_PROT_ALL) == VM_PROT_NONE) { + /* + * For PIE, extend page zero rather than moving it. Extending + * page zero keeps early allocations from falling predictably + * between the end of page zero and the beginning of the first + * slid segment. + */ + seg_size += slide; + slide = 0; +#if CONFIG_EMBEDDED + prohibit_pagezero_mapping = TRUE; +#endif + /* XXX (4596982) this interferes with Rosetta, so limit to 64-bit tasks */ + if (scp->cmd == LC_SEGMENT_64) { + prohibit_pagezero_mapping = TRUE; + } + + if (prohibit_pagezero_mapping) { + /* + * This is a "page zero" segment: it starts at address 0, + * is not mapped from the binary file and is not accessible. + * User-space should never be able to access that memory, so + * make it completely off limits by raising the VM map's + * minimum offset. + */ + ret = vm_map_raise_min_offset(map, seg_size); + if (ret != KERN_SUCCESS) { + return (LOAD_FAILURE); + } + return (LOAD_SUCCESS); + } + } + + /* If a non-zero slide was specified by the caller, apply now */ + map_addr += slide; + + if (map_addr < result->min_vm_addr) + result->min_vm_addr = map_addr; + if (map_addr+seg_size > result->max_vm_addr) + result->max_vm_addr = map_addr+seg_size; - map_offset = pager_offset + scp->fileoff; + if (map == VM_MAP_NULL) + return (LOAD_SUCCESS); + + map_offset = pager_offset + scp->fileoff; /* limited to 32 bits */ if (map_size > 0) { initprot = (scp->initprot) & VM_PROT_ALL; @@ -559,18 +968,14 @@ load_segment( /* * Map a copy of the file into the address space. */ - ret = vm_map(map, - &map_addr, map_size, (vm_offset_t)0, FALSE, - pager, map_offset, TRUE, + ret = vm_map_enter_mem_object_control(map, + &map_addr, map_size, (mach_vm_offset_t)0, + VM_FLAGS_FIXED, control, map_offset, TRUE, initprot, maxprot, VM_INHERIT_DEFAULT); if (ret != KERN_SUCCESS) - return(LOAD_NOSPACE); + return (LOAD_NOSPACE); -#if 1 - if (print_map_addr) - printf("LSegment: Mapped addr= %x; size = %x\n", map_addr, map_size); -#endif /* 1 */ /* * If the file didn't end on a page boundary, * we need to zero the leftover. @@ -578,20 +983,20 @@ load_segment( delta_size = map_size - scp->filesize; #if FIXME if (delta_size > 0) { - vm_offset_t tmp; + mach_vm_offset_t tmp; - ret = vm_allocate(kernel_map, &tmp, delta_size, TRUE); + ret = mach_vm_allocate(kernel_map, &tmp, delta_size, VM_FLAGS_ANYWHERE); if (ret != KERN_SUCCESS) return(LOAD_RESOURCE); if (copyout(tmp, map_addr + scp->filesize, delta_size)) { - (void) vm_deallocate( + (void) mach_vm_deallocate( kernel_map, tmp, delta_size); - return(LOAD_FAILURE); + return (LOAD_FAILURE); } - - (void) vm_deallocate(kernel_map, tmp, delta_size); + + (void) mach_vm_deallocate(kernel_map, tmp, delta_size); } #endif /* FIXME */ } @@ -603,71 +1008,161 @@ load_segment( */ delta_size = seg_size - map_size; if (delta_size > 0) { - vm_offset_t tmp = map_addr + map_size; + mach_vm_offset_t tmp = map_addr + map_size; - ret = vm_allocate(map, &tmp, delta_size, FALSE); + ret = mach_vm_map(map, &tmp, delta_size, 0, VM_FLAGS_FIXED, + NULL, 0, FALSE, + scp->initprot, scp->maxprot, + VM_INHERIT_DEFAULT); if (ret != KERN_SUCCESS) return(LOAD_NOSPACE); } - /* - * Set protection values. (Note: ignore errors!) - */ + if ( (scp->fileoff == 0) && (scp->filesize != 0) ) + result->mach_header = map_addr; + + if (scp->flags & SG_PROTECTED_VERSION_1) { + ret = unprotect_segment(scp->fileoff, + scp->filesize, + vp, + pager_offset, + map, + map_addr, + map_size); + } else { + ret = LOAD_SUCCESS; + } + if (LOAD_SUCCESS == ret && filetype == MH_DYLINKER && + result->all_image_info_addr == MACH_VM_MIN_ADDRESS) + note_all_image_info_section(scp, + LC_SEGMENT_64 == lcp->cmd, single_section_size, + (const char *)lcp + segment_command_size, slide, result); + + if ((result->entry_point >= map_addr) && (result->entry_point < (map_addr + map_size))) + result->validentry = 1; + + return ret; +} + + + +static +load_return_t +load_main( + struct entry_point_command *epc, + thread_t thread, + int64_t slide, + load_result_t *result +) +{ + mach_vm_offset_t addr; + kern_return_t ret; + + if (epc->cmdsize < sizeof(*epc)) + return (LOAD_BADMACHO); + if (result->thread_count != 0) { + printf("load_main: already have a thread!"); + return (LOAD_FAILURE); + } - if (scp->maxprot != VM_PROT_DEFAULT) { - (void) vm_protect(map, - map_addr, seg_size, - TRUE, scp->maxprot); + if (thread == THREAD_NULL) + return (LOAD_SUCCESS); + + /* LC_MAIN specifies stack size but not location */ + if (epc->stacksize) { + result->prog_stack_size = 1; + result->user_stack_size = epc->stacksize; + } else { + result->prog_stack_size = 0; + result->user_stack_size = MAXSSIZ; } - if (scp->initprot != VM_PROT_DEFAULT) { - (void) vm_protect(map, - map_addr, seg_size, - FALSE, scp->initprot); + result->prog_allocated_stack = 0; + + /* use default location for stack */ + ret = thread_userstackdefault(thread, &addr); + if (ret != KERN_SUCCESS) + return(LOAD_FAILURE); + + /* The stack slides down from the default location */ + result->user_stack = addr; + result->user_stack -= slide; + + /* kernel does *not* use entryoff from LC_MAIN. Dyld uses it. */ + result->needs_dynlinker = TRUE; + result->validentry = TRUE; + + ret = thread_state_initialize( thread ); + if (ret != KERN_SUCCESS) { + return(LOAD_FAILURE); } - if ( (scp->fileoff == 0) && (scp->filesize != 0) ) - result->mach_header = map_addr; + + result->unixproc = TRUE; + result->thread_count++; + return(LOAD_SUCCESS); } + static load_return_t load_unixthread( struct thread_command *tcp, - thread_act_t thr_act, + thread_t thread, + int64_t slide, load_result_t *result ) { - thread_t thread = current_thread(); load_return_t ret; int customstack =0; + mach_vm_offset_t addr; - if (result->thread_count != 0) + if (tcp->cmdsize < sizeof(*tcp)) + return (LOAD_BADMACHO); + if (result->thread_count != 0) { + printf("load_unixthread: already have a thread!"); return (LOAD_FAILURE); + } + + if (thread == THREAD_NULL) + return (LOAD_SUCCESS); - thread = getshuttle_thread(thr_act); ret = load_threadstack(thread, - (unsigned long *)(((vm_offset_t)tcp) + + (uint32_t *)(((vm_offset_t)tcp) + sizeof(struct thread_command)), tcp->cmdsize - sizeof(struct thread_command), - &result->user_stack, + &addr, &customstack); if (ret != LOAD_SUCCESS) return(ret); - if (customstack) - result->customstack = 1; - else - result->customstack = 0; + /* LC_UNIXTHREAD optionally specifies stack size and location */ + + if (customstack) { + result->prog_stack_size = 0; /* unknown */ + result->prog_allocated_stack = 1; + } else { + result->prog_allocated_stack = 0; + result->prog_stack_size = 0; + result->user_stack_size = MAXSSIZ; + } + + /* The stack slides down from the default location */ + result->user_stack = addr; + result->user_stack -= slide; + ret = load_threadentry(thread, - (unsigned long *)(((vm_offset_t)tcp) + + (uint32_t *)(((vm_offset_t)tcp) + sizeof(struct thread_command)), tcp->cmdsize - sizeof(struct thread_command), - &result->entry_point); + &addr); if (ret != LOAD_SUCCESS) return(ret); + result->entry_point = addr; + result->entry_point += slide; + ret = load_threadstate(thread, - (unsigned long *)(((vm_offset_t)tcp) + + (uint32_t *)(((vm_offset_t)tcp) + sizeof(struct thread_command)), tcp->cmdsize - sizeof(struct thread_command)); if (ret != LOAD_SUCCESS) @@ -679,100 +1174,48 @@ load_unixthread( return(LOAD_SUCCESS); } -static -load_return_t -load_thread( - struct thread_command *tcp, - thread_act_t thr_act, - load_result_t *result -) -{ - thread_t thread; - kern_return_t kret; - load_return_t lret; - task_t task; - int customstack=0; - - task = get_threadtask(thr_act); - thread = getshuttle_thread(thr_act); - - /* if count is 0; same as thr_act */ - if (result->thread_count != 0) { - kret = thread_create(task, &thread); - if (kret != KERN_SUCCESS) - return(LOAD_RESOURCE); - thread_deallocate(thread); - } - - lret = load_threadstate(thread, - (unsigned long *)(((vm_offset_t)tcp) + - sizeof(struct thread_command)), - tcp->cmdsize - sizeof(struct thread_command)); - if (lret != LOAD_SUCCESS) - return (lret); - - if (result->thread_count == 0) { - lret = load_threadstack(thread, - (unsigned long *)(((vm_offset_t)tcp) + - sizeof(struct thread_command)), - tcp->cmdsize - sizeof(struct thread_command), - &result->user_stack, - &customstack); - if (customstack) - result->customstack = 1; - else - result->customstack = 0; - - if (lret != LOAD_SUCCESS) - return(lret); - - lret = load_threadentry(thread, - (unsigned long *)(((vm_offset_t)tcp) + - sizeof(struct thread_command)), - tcp->cmdsize - sizeof(struct thread_command), - &result->entry_point); - if (lret != LOAD_SUCCESS) - return(lret); - } - /* - * Resume thread now, note that this means that the thread - * commands should appear after all the load commands to - * be sure they don't reference anything not yet mapped. - */ - else - thread_resume(thread); - - result->thread_count++; - - return(LOAD_SUCCESS); -} - static load_return_t load_threadstate( thread_t thread, - unsigned long *ts, - unsigned long total_size + uint32_t *ts, + uint32_t total_size ) { kern_return_t ret; - unsigned long size; + uint32_t size; int flavor; + uint32_t thread_size; + ret = thread_state_initialize( thread ); + if (ret != KERN_SUCCESS) { + return(LOAD_FAILURE); + } + /* - * Set the thread state. + * Set the new thread state; iterate through the state flavors in + * the mach-o file. */ - while (total_size > 0) { flavor = *ts++; size = *ts++; - total_size -= (size+2)*sizeof(unsigned long); - if (total_size < 0) + if (UINT32_MAX-2 < size || + UINT32_MAX/sizeof(uint32_t) < size+2) + return (LOAD_BADMACHO); + thread_size = (size+2)*sizeof(uint32_t); + if (thread_size > total_size) return(LOAD_BADMACHO); - ret = thread_setstatus(getact_thread(thread), flavor, ts, size); - if (ret != KERN_SUCCESS) + total_size -= thread_size; + /* + * Third argument is a kernel space pointer; it gets cast + * to the appropriate type in machine_thread_set_state() + * based on the value of flavor. + */ + ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size); + if (ret != KERN_SUCCESS) { return(LOAD_FAILURE); - ts += size; /* ts is a (unsigned long *) */ + } + ts += size; /* ts is a (uint32_t *) */ } return(LOAD_SUCCESS); } @@ -781,28 +1224,38 @@ static load_return_t load_threadstack( thread_t thread, - unsigned long *ts, - unsigned long total_size, - vm_offset_t *user_stack, + uint32_t *ts, + uint32_t total_size, + mach_vm_offset_t *user_stack, int *customstack ) { kern_return_t ret; - unsigned long size; + uint32_t size; int flavor; + uint32_t stack_size; while (total_size > 0) { flavor = *ts++; size = *ts++; - total_size -= (size+2)*sizeof(unsigned long); - if (total_size < 0) + if (UINT32_MAX-2 < size || + UINT32_MAX/sizeof(uint32_t) < size+2) + return (LOAD_BADMACHO); + stack_size = (size+2)*sizeof(uint32_t); + if (stack_size > total_size) return(LOAD_BADMACHO); - *user_stack = USRSTACK; - ret = thread_userstack(thread, flavor, ts, size, - user_stack, customstack); - if (ret != KERN_SUCCESS) + total_size -= stack_size; + + /* + * Third argument is a kernel space pointer; it gets cast + * to the appropriate type in thread_userstack() based on + * the value of flavor. + */ + ret = thread_userstack(thread, flavor, (thread_state_t)ts, size, user_stack, customstack); + if (ret != KERN_SUCCESS) { return(LOAD_FAILURE); - ts += size; /* ts is a (unsigned long *) */ + } + ts += size; /* ts is a (uint32_t *) */ } return(LOAD_SUCCESS); } @@ -811,57 +1264,81 @@ static load_return_t load_threadentry( thread_t thread, - unsigned long *ts, - unsigned long total_size, - vm_offset_t *entry_point + uint32_t *ts, + uint32_t total_size, + mach_vm_offset_t *entry_point ) { kern_return_t ret; - unsigned long size; + uint32_t size; int flavor; + uint32_t entry_size; /* * Set the thread state. */ - *entry_point = 0; + *entry_point = MACH_VM_MIN_ADDRESS; while (total_size > 0) { flavor = *ts++; size = *ts++; - total_size -= (size+2)*sizeof(unsigned long); - if (total_size < 0) + if (UINT32_MAX-2 < size || + UINT32_MAX/sizeof(uint32_t) < size+2) + return (LOAD_BADMACHO); + entry_size = (size+2)*sizeof(uint32_t); + if (entry_size > total_size) return(LOAD_BADMACHO); - ret = thread_entrypoint(thread, flavor, ts, size, entry_point); - if (ret != KERN_SUCCESS) + total_size -= entry_size; + /* + * Third argument is a kernel space pointer; it gets cast + * to the appropriate type in thread_entrypoint() based on + * the value of flavor. + */ + ret = thread_entrypoint(thread, flavor, (thread_state_t)ts, size, entry_point); + if (ret != KERN_SUCCESS) { return(LOAD_FAILURE); - ts += size; /* ts is a (unsigned long *) */ + } + ts += size; /* ts is a (uint32_t *) */ } return(LOAD_SUCCESS); } +struct macho_data { + struct nameidata __nid; + union macho_vnode_header { + struct mach_header mach_header; + struct fat_header fat_header; + char __pad[512]; + } __header; +}; -static -load_return_t +static load_return_t load_dylinker( struct dylinker_command *lcp, + integer_t archbits, vm_map_t map, - thread_act_t thr_act, + thread_t thread, int depth, - load_result_t *result, - boolean_t clean_regions + int64_t slide, + load_result_t *result ) { char *name; char *p; - struct vnode *vp; - struct mach_header header; - unsigned long file_offset; - unsigned long macho_size; - vm_map_t copy_map; - load_result_t myresult; + struct vnode *vp = NULLVP; /* set by get_macho_vnode() */ + struct mach_header *header; + off_t file_offset = 0; /* set by get_macho_vnode() */ + off_t macho_size = 0; /* set by get_macho_vnode() */ + load_result_t *myresult; kern_return_t ret; - vm_map_copy_t tmp; - vm_offset_t dyl_start, map_addr; - vm_size_t dyl_length; + struct macho_data *macho_data; + struct { + struct mach_header __header; + load_result_t __myresult; + struct macho_data __macho_data; + } *dyld_data; + + if (lcp->cmdsize < sizeof(*lcp)) + return (LOAD_BADMACHO); name = (char *)lcp + lcp->name.offset; /* @@ -873,215 +1350,475 @@ load_dylinker( return(LOAD_BADMACHO); } while (*p++); - ret = get_macho_vnode(name, &header, &file_offset, &macho_size, &vp); + /* Allocate wad-of-data from heap to reduce excessively deep stacks */ + + MALLOC(dyld_data, void *, sizeof (*dyld_data), M_TEMP, M_WAITOK); + header = &dyld_data->__header; + myresult = &dyld_data->__myresult; + macho_data = &dyld_data->__macho_data; + + ret = get_macho_vnode(name, archbits, header, + &file_offset, &macho_size, macho_data, &vp); if (ret) - return (ret); - - myresult = (load_result_t) { 0 }; + goto novp_out; + + *myresult = load_result_null; /* - * Load the Mach-O. + * First try to map dyld in directly. This should work most of + * the time since there shouldn't normally be something already + * mapped to its address. */ - - copy_map = vm_map_create(pmap_create(macho_size), - get_map_min(map), get_map_max( map), TRUE); - ret = parse_machfile(vp, copy_map, thr_act, &header, - file_offset, macho_size, - depth, &myresult, clean_regions); + ret = parse_machfile(vp, map, thread, header, file_offset, + macho_size, depth, slide, myresult); - if (ret) - goto out; + /* + * If it turned out something was in the way, then we'll take + * take this longer path to preflight dyld's vm ranges, then + * map it at a free location in the address space. + */ - if (get_map_nentries(copy_map) > 0) { + if (ret == LOAD_NOSPACE) { + mach_vm_offset_t dyl_start, map_addr; + mach_vm_size_t dyl_length; + int64_t slide_amount; - dyl_start = get_map_start(copy_map); - dyl_length = get_map_end(copy_map) - dyl_start; + *myresult = load_result_null; - map_addr = dyl_start; - ret = vm_allocate(map, &map_addr, dyl_length, FALSE); - if (ret != KERN_SUCCESS) { - ret = vm_allocate(map, &map_addr, dyl_length, TRUE); + /* + * Preflight parsing the Mach-O file with a NULL + * map, which will return the ranges needed for a + * subsequent map attempt (with a slide) in "myresult" + */ + ret = parse_machfile(vp, VM_MAP_NULL, THREAD_NULL, header, + file_offset, macho_size, depth, 0 /* slide */, myresult); + + if (ret != LOAD_SUCCESS) { + goto out; } + dyl_start = myresult->min_vm_addr; + dyl_length = myresult->max_vm_addr - myresult->min_vm_addr; + + dyl_length += slide; + + /* To find an appropriate load address, do a quick allocation */ + map_addr = dyl_start; + ret = mach_vm_allocate(map, &map_addr, dyl_length, VM_FLAGS_ANYWHERE); if (ret != KERN_SUCCESS) { ret = LOAD_NOSPACE; goto out; - } - ret = vm_map_copyin(copy_map, dyl_start, dyl_length, TRUE, - &tmp); + + ret = mach_vm_deallocate(map, map_addr, dyl_length); if (ret != KERN_SUCCESS) { - (void) vm_map_remove(map, - map_addr, - map_addr + dyl_length, - VM_MAP_NO_FLAGS); + ret = LOAD_NOSPACE; goto out; } + + if (map_addr < dyl_start) + slide_amount = -(int64_t)(dyl_start - map_addr); + else + slide_amount = (int64_t)(map_addr - dyl_start); + + slide_amount += slide; + + *myresult = load_result_null; + + ret = parse_machfile(vp, map, thread, header, + file_offset, macho_size, depth, slide_amount, myresult); + + if (ret) { + goto out; + } + } - ret = vm_map_copy_overwrite(map, map_addr, tmp, FALSE); - if (ret != KERN_SUCCESS) { - vm_map_copy_discard(tmp); - (void) vm_map_remove(map, - map_addr, - map_addr + dyl_length, - VM_MAP_NO_FLAGS); - goto out; } - - if (map_addr != dyl_start) - myresult.entry_point += (map_addr - dyl_start); - } else - ret = LOAD_FAILURE; - if (ret == LOAD_SUCCESS) { result->dynlinker = TRUE; - result->entry_point = myresult.entry_point; - ubc_map(vp); + result->entry_point = myresult->entry_point; + result->validentry = myresult->validentry; + result->all_image_info_addr = myresult->all_image_info_addr; + result->all_image_info_size = myresult->all_image_info_size; } out: - vm_map_deallocate(copy_map); - - vrele(vp); + vnode_put(vp); +novp_out: + FREE(dyld_data, M_TEMP); return (ret); } +static load_return_t +load_code_signature( + struct linkedit_data_command *lcp, + struct vnode *vp, + off_t macho_offset, + off_t macho_size, + cpu_type_t cputype, + load_result_t *result) +{ + int ret; + kern_return_t kr; + vm_offset_t addr; + int resid; + struct cs_blob *blob; + int error; + vm_size_t blob_size; + + addr = 0; + blob = NULL; + + if (lcp->cmdsize != sizeof (struct linkedit_data_command) || + lcp->dataoff + lcp->datasize > macho_size) { + ret = LOAD_BADMACHO; + goto out; + } + + blob = ubc_cs_blob_get(vp, cputype, -1); + if (blob != NULL) { + /* we already have a blob for this vnode and cputype */ + if (blob->csb_cpu_type == cputype && + blob->csb_base_offset == macho_offset && + blob->csb_mem_size == lcp->datasize) { + /* it matches the blob we want here: we're done */ + ret = LOAD_SUCCESS; + } else { + /* the blob has changed for this vnode: fail ! */ + ret = LOAD_BADMACHO; + } + goto out; + } + + blob_size = lcp->datasize; + kr = ubc_cs_blob_allocate(&addr, &blob_size); + if (kr != KERN_SUCCESS) { + ret = LOAD_NOSPACE; + goto out; + } + + resid = 0; + error = vn_rdwr(UIO_READ, + vp, + (caddr_t) addr, + lcp->datasize, + macho_offset + lcp->dataoff, + UIO_SYSSPACE, + 0, + kauth_cred_get(), + &resid, + current_proc()); + if (error || resid != 0) { + ret = LOAD_IOERROR; + goto out; + } + + if (ubc_cs_blob_add(vp, + cputype, + macho_offset, + addr, + lcp->datasize)) { + ret = LOAD_FAILURE; + goto out; + } else { + /* ubc_cs_blob_add() has consumed "addr" */ + addr = 0; + } + +#if CHECK_CS_VALIDATION_BITMAP + ubc_cs_validation_bitmap_allocate( vp ); +#endif + + blob = ubc_cs_blob_get(vp, cputype, -1); + + ret = LOAD_SUCCESS; +out: + if (result && ret == LOAD_SUCCESS) { + result->csflags |= blob->csb_flags; + } + if (addr != 0) { + ubc_cs_blob_deallocate(addr, blob_size); + addr = 0; + } + + return ret; +} + + +#if CONFIG_CODE_DECRYPTION + +static load_return_t +set_code_unprotect( + struct encryption_info_command *eip, + caddr_t addr, + vm_map_t map, + int64_t slide, + struct vnode *vp) +{ + int result, len; + pager_crypt_info_t crypt_info; + const char * cryptname = 0; + char *vpath; + + size_t offset; + struct segment_command_64 *seg64; + struct segment_command *seg32; + vm_map_offset_t map_offset, map_size; + kern_return_t kr; + + if (eip->cmdsize < sizeof(*eip)) return LOAD_BADMACHO; + + switch(eip->cryptid) { + case 0: + /* not encrypted, just an empty load command */ + return LOAD_SUCCESS; + case 1: + cryptname="com.apple.unfree"; + break; + case 0x10: + /* some random cryptid that you could manually put into + * your binary if you want NULL */ + cryptname="com.apple.null"; + break; + default: + return LOAD_BADMACHO; + } + + if (map == VM_MAP_NULL) return (LOAD_SUCCESS); + if (NULL == text_crypter_create) return LOAD_FAILURE; + + MALLOC_ZONE(vpath, char *, MAXPATHLEN, M_NAMEI, M_WAITOK); + if(vpath == NULL) return LOAD_FAILURE; + + len = MAXPATHLEN; + result = vn_getpath(vp, vpath, &len); + if(result) { + FREE_ZONE(vpath, MAXPATHLEN, M_NAMEI); + return LOAD_FAILURE; + } + + /* set up decrypter first */ + kr=text_crypter_create(&crypt_info, cryptname, (void*)vpath); + FREE_ZONE(vpath, MAXPATHLEN, M_NAMEI); + + if(kr) { + printf("set_code_unprotect: unable to create decrypter %s, kr=%d\n", + cryptname, kr); + return LOAD_RESOURCE; + } + + /* this is terrible, but we have to rescan the load commands to find the + * virtual address of this encrypted stuff. This code is gonna look like + * the dyld source one day... */ + struct mach_header *header = (struct mach_header *)addr; + size_t mach_header_sz = sizeof(struct mach_header); + if (header->magic == MH_MAGIC_64 || + header->magic == MH_CIGAM_64) { + mach_header_sz = sizeof(struct mach_header_64); + } + offset = mach_header_sz; + uint32_t ncmds = header->ncmds; + while (ncmds--) { + /* + * Get a pointer to the command. + */ + struct load_command *lcp = (struct load_command *)(addr + offset); + offset += lcp->cmdsize; + + switch(lcp->cmd) { + case LC_SEGMENT_64: + seg64 = (struct segment_command_64 *)lcp; + if ((seg64->fileoff <= eip->cryptoff) && + (seg64->fileoff+seg64->filesize >= + eip->cryptoff+eip->cryptsize)) { + map_offset = seg64->vmaddr + eip->cryptoff - seg64->fileoff + slide; + map_size = eip->cryptsize; + goto remap_now; + } + case LC_SEGMENT: + seg32 = (struct segment_command *)lcp; + if ((seg32->fileoff <= eip->cryptoff) && + (seg32->fileoff+seg32->filesize >= + eip->cryptoff+eip->cryptsize)) { + map_offset = seg32->vmaddr + eip->cryptoff - seg32->fileoff + slide; + map_size = eip->cryptsize; + goto remap_now; + } + } + } + + /* if we get here, did not find anything */ + return LOAD_BADMACHO; + +remap_now: + /* now remap using the decrypter */ + kr = vm_map_apple_protected(map, map_offset, map_offset+map_size, &crypt_info); + if(kr) { + printf("set_code_unprotect(): mapping failed with %x\n", kr); + crypt_info.crypt_end(crypt_info.crypt_ops); + return LOAD_PROTECT; + } + + return LOAD_SUCCESS; +} + +#endif + +/* + * This routine exists to support the load_dylinker(). + * + * This routine has its own, separate, understanding of the FAT file format, + * which is terrifically unfortunate. + */ static load_return_t get_macho_vnode( char *path, + integer_t archbits, struct mach_header *mach_header, - unsigned long *file_offset, - unsigned long *macho_size, + off_t *file_offset, + off_t *macho_size, + struct macho_data *data, struct vnode **vpp ) { struct vnode *vp; - struct vattr attr, *atp; - struct nameidata nid, *ndp; - struct proc *p = current_proc(); /* XXXX */ + vfs_context_t ctx = vfs_context_current(); + proc_t p = vfs_context_proc(ctx); + kauth_cred_t kerncred; + struct nameidata *ndp = &data->__nid; boolean_t is_fat; struct fat_arch fat_arch; - int error = KERN_SUCCESS; + int error; int resid; - union { - struct mach_header mach_header; - struct fat_header fat_header; - char pad[512]; - } header; + union macho_vnode_header *header = &data->__header; off_t fsize = (off_t)0; - struct ucred *cred = p->p_ucred; - - ndp = &nid; - atp = &attr; - + + /* + * Capture the kernel credential for use in the actual read of the + * file, since the user doing the execution may have execute rights + * but not read rights, but to exec something, we have to either map + * or read it into the new process address space, which requires + * read rights. This is to deal with lack of common credential + * serialization code which would treat NOCRED as "serialize 'root'". + */ + kerncred = vfs_context_ucred(vfs_context_kernel()); + /* init the namei data to point the file user's program name */ - NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, path, p); + NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW | LOCKLEAF, UIO_SYSSPACE, CAST_USER_ADDR_T(path), ctx); - if (error = namei(ndp)) + if ((error = namei(ndp)) != 0) { + if (error == ENOENT) { + error = LOAD_ENOENT; + } else { + error = LOAD_FAILURE; + } return(error); - + } + nameidone(ndp); vp = ndp->ni_vp; - + /* check for regular file */ if (vp->v_type != VREG) { - error = EACCES; + error = LOAD_PROTECT; goto bad1; } - /* get attributes */ - if (error = VOP_GETATTR(vp, &attr, cred, p)) + /* get size */ + if ((error = vnode_size(vp, &fsize, ctx)) != 0) { + error = LOAD_FAILURE; goto bad1; + } /* Check mount point */ if (vp->v_mount->mnt_flag & MNT_NOEXEC) { - error = EACCES; + error = LOAD_PROTECT; goto bad1; } - if ((vp->v_mount->mnt_flag & MNT_NOSUID) || (p->p_flag & P_TRACED)) - atp->va_mode &= ~(VSUID | VSGID); - - /* check access. for root we have to see if any exec bit on */ - if (error = VOP_ACCESS(vp, VEXEC, cred, p)) - goto bad1; - if ((atp->va_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) == 0) { - error = EACCES; + /* check access */ + if ((error = vnode_authorize(vp, NULL, KAUTH_VNODE_EXECUTE, ctx)) != 0) { + error = LOAD_PROTECT; goto bad1; } - /* hold the vnode for the IO */ - if (UBCINFOEXISTS(vp) && !ubc_hold(vp)) { - error = ENOENT; + /* try to open it */ + if ((error = VNOP_OPEN(vp, FREAD, ctx)) != 0) { + error = LOAD_PROTECT; goto bad1; } - /* try to open it */ - if (error = VOP_OPEN(vp, FREAD, cred, p)) { - ubc_rele(vp); - goto bad1; + if ((error = vn_rdwr(UIO_READ, vp, (caddr_t)header, sizeof (*header), 0, + UIO_SYSSPACE, IO_NODELOCKED, kerncred, &resid, p)) != 0) { + error = LOAD_IOERROR; + goto bad2; } - if(error = vn_rdwr(UIO_READ, vp, (caddr_t)&header, sizeof(header), 0, - UIO_SYSSPACE, IO_NODELOCKED, cred, &resid, p)) + if (header->mach_header.magic == MH_MAGIC || + header->mach_header.magic == MH_MAGIC_64) { + is_fat = FALSE; + } else if (header->fat_header.magic == FAT_MAGIC || + header->fat_header.magic == FAT_CIGAM) { + is_fat = TRUE; + } else { + error = LOAD_BADMACHO; goto bad2; - - if (header.mach_header.magic == MH_MAGIC) - is_fat = FALSE; - else if (header.fat_header.magic == FAT_MAGIC || - header.fat_header.magic == FAT_CIGAM) - is_fat = TRUE; - else { - error = LOAD_BADMACHO; - goto bad2; } if (is_fat) { /* Look up our architecture in the fat file. */ - error = fatfile_getarch(vp, (vm_offset_t)(&header.fat_header), &fat_arch); + error = fatfile_getarch_with_bits(vp, archbits, + (vm_offset_t)(&header->fat_header), &fat_arch); if (error != LOAD_SUCCESS) goto bad2; /* Read the Mach-O header out of it */ - error = vn_rdwr(UIO_READ, vp, &header.mach_header, - sizeof(header.mach_header), fat_arch.offset, - UIO_SYSSPACE, IO_NODELOCKED, cred, &resid, p); + error = vn_rdwr(UIO_READ, vp, (caddr_t)&header->mach_header, + sizeof (header->mach_header), fat_arch.offset, + UIO_SYSSPACE, IO_NODELOCKED, kerncred, &resid, p); if (error) { - error = LOAD_FAILURE; + error = LOAD_IOERROR; goto bad2; } /* Is this really a Mach-O? */ - if (header.mach_header.magic != MH_MAGIC) { + if (header->mach_header.magic != MH_MAGIC && + header->mach_header.magic != MH_MAGIC_64) { error = LOAD_BADMACHO; goto bad2; } *file_offset = fat_arch.offset; - *macho_size = fsize = fat_arch.size; + *macho_size = fat_arch.size; } else { + /* + * Force get_macho_vnode() to fail if the architecture bits + * do not match the expected architecture bits. This in + * turn causes load_dylinker() to fail for the same reason, + * so it ensures the dynamic linker and the binary are in + * lock-step. This is potentially bad, if we ever add to + * the CPU_ARCH_* bits any bits that are desirable but not + * required, since the dynamic linker might work, but we will + * refuse to load it because of this check. + */ + if ((cpu_type_t)(header->mach_header.cputype & CPU_ARCH_MASK) != archbits) { + error = LOAD_BADARCH; + goto bad2; + } *file_offset = 0; - *macho_size = fsize = attr.va_size; + *macho_size = fsize; } - *mach_header = header.mach_header; + *mach_header = header->mach_header; *vpp = vp; - if (UBCISVALID(vp)) - ubc_setsize(vp, fsize); /* XXX why? */ - - VOP_UNLOCK(vp, 0, p); - ubc_rele(vp); - return (error); -bad2: - VOP_UNLOCK(vp, 0, p); - error = VOP_CLOSE(vp, FREAD, cred, p); - ubc_rele(vp); - vrele(vp); + ubc_setsize(vp, fsize); return (error); +bad2: + (void) VNOP_CLOSE(vp, FREAD, ctx); bad1: - vput(vp); + vnode_put(vp); return(error); }