diff options
Diffstat (limited to 'sys/kern/imgact_elf.c')
| -rw-r--r-- | sys/kern/imgact_elf.c | 992 |
1 files changed, 992 insertions, 0 deletions
diff --git a/sys/kern/imgact_elf.c b/sys/kern/imgact_elf.c new file mode 100644 index 0000000..a0a2284 --- /dev/null +++ b/sys/kern/imgact_elf.c @@ -0,0 +1,992 @@ +/*- + * Copyright (c) 1995-1996 Søren Schmidt + * Copyright (c) 1996 Peter Wemm + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer + * in this position and unchanged. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software withough specific prior written permission + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * $Id: imgact_elf.c,v 1.43 1998/12/04 22:54:51 archie Exp $ + */ + +#include "opt_rlimit.h" + +#include <sys/param.h> +#include <sys/acct.h> +#include <sys/exec.h> +#include <sys/fcntl.h> +#include <sys/imgact.h> +#include <sys/imgact_elf.h> +#include <sys/kernel.h> +#include <sys/malloc.h> +#include <sys/mman.h> +#include <sys/namei.h> +#include <sys/pioctl.h> +#include <sys/proc.h> +#include <sys/procfs.h> +#include <sys/resourcevar.h> +#include <sys/signalvar.h> +#include <sys/stat.h> +#include <sys/syscall.h> +#include <sys/sysctl.h> +#include <sys/sysent.h> +#include <sys/systm.h> +#include <sys/vnode.h> + +#include <vm/vm.h> +#include <vm/vm_kern.h> +#include <vm/vm_param.h> +#include <vm/pmap.h> +#include <sys/lock.h> +#include <vm/vm_map.h> +#include <vm/vm_object.h> +#include <vm/vm_prot.h> +#include <vm/vm_extern.h> + +#include <machine/elf.h> +#include <machine/md_var.h> + +__ElfType(Brandinfo); +__ElfType(Auxargs); + +static int elf_check_header __P((const Elf_Ehdr *hdr, int type)); +static int elf_freebsd_fixup __P((long **stack_base, + struct image_params *imgp)); +static int elf_load_file __P((struct proc *p, char *file, u_long *addr, + u_long *entry)); +static int elf_load_section __P((struct proc *p, + struct vmspace *vmspace, struct vnode *vp, + vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz, + vm_prot_t prot)); +static int exec_elf_imgact __P((struct image_params *imgp)); + +static int elf_trace = 0; +SYSCTL_INT(_debug, OID_AUTO, elf_trace, CTLFLAG_RW, &elf_trace, 0, ""); + +static struct sysentvec elf_freebsd_sysvec = { + SYS_MAXSYSCALL, + sysent, + 0, + 0, + 0, + 0, + 0, + 0, + elf_freebsd_fixup, + sendsig, + sigcode, + &szsigcode, + 0, + "FreeBSD ELF", + elf_coredump +}; + +static Elf_Brandinfo freebsd_brand_info = { + "FreeBSD", + "", + "/usr/libexec/ld-elf.so.1", + &elf_freebsd_sysvec + }; +static Elf_Brandinfo *elf_brand_list[MAX_BRANDS] = { + &freebsd_brand_info, + NULL, NULL, NULL, + NULL, NULL, NULL, NULL + }; + +int +elf_insert_brand_entry(Elf_Brandinfo *entry) +{ + int i; + + for (i=1; i<MAX_BRANDS; i++) { + if (elf_brand_list[i] == NULL) { + elf_brand_list[i] = entry; + break; + } + } + if (i == MAX_BRANDS) + return -1; + return 0; +} + +int +elf_remove_brand_entry(Elf_Brandinfo *entry) +{ + int i; + + for (i=1; i<MAX_BRANDS; i++) { + if (elf_brand_list[i] == entry) { + elf_brand_list[i] = NULL; + break; + } + } + if (i == MAX_BRANDS) + return -1; + return 0; +} + +static int +elf_check_header(const Elf_Ehdr *hdr, int type) +{ + if (!IS_ELF(*hdr) || + hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || + hdr->e_ident[EI_DATA] != ELF_TARG_DATA || + hdr->e_ident[EI_VERSION] != EV_CURRENT) + return ENOEXEC; + + if (!ELF_MACHINE_OK(hdr->e_machine)) + return ENOEXEC; + + if (hdr->e_type != type || hdr->e_version != ELF_TARG_VER) + return ENOEXEC; + + return 0; +} + +static int +elf_load_section(struct proc *p, struct vmspace *vmspace, struct vnode *vp, vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot) +{ + size_t map_len; + vm_offset_t map_addr; + int error, rv; + size_t copy_len; + vm_object_t object; + vm_offset_t file_addr; + vm_offset_t data_buf = 0; + + object = vp->v_object; + error = 0; + + map_addr = trunc_page((vm_offset_t)vmaddr); + file_addr = trunc_page(offset); + + /* + * We have two choices. We can either clear the data in the last page + * of an oversized mapping, or we can start the anon mapping a page + * early and copy the initialized data into that first page. We + * choose the second.. + */ + if (memsz > filsz) + map_len = trunc_page(offset+filsz) - file_addr; + else + map_len = round_page(offset+filsz) - file_addr; + + if (map_len != 0) { + vm_object_reference(object); + vm_map_lock(&vmspace->vm_map); + rv = vm_map_insert(&vmspace->vm_map, + object, + file_addr, /* file offset */ + map_addr, /* virtual start */ + map_addr + map_len,/* virtual end */ + prot, + VM_PROT_ALL, + MAP_COPY_NEEDED | MAP_COPY_ON_WRITE); + vm_map_unlock(&vmspace->vm_map); + if (rv != KERN_SUCCESS) + return EINVAL; + + /* prefault the page tables */ + pmap_object_init_pt(&vmspace->vm_pmap, + map_addr, + object, + (vm_pindex_t) OFF_TO_IDX(file_addr), + map_len, + 0); + + /* we can stop now if we've covered it all */ + if (memsz == filsz) + return 0; + } + + + /* + * We have to get the remaining bit of the file into the first part + * of the oversized map segment. This is normally because the .data + * segment in the file is extended to provide bss. It's a neat idea + * to try and save a page, but it's a pain in the behind to implement. + */ + copy_len = (offset + filsz) - trunc_page(offset + filsz); + map_addr = trunc_page((vm_offset_t)vmaddr + filsz); + map_len = round_page((vm_offset_t)vmaddr + memsz) - map_addr; + + /* This had damn well better be true! */ + if (map_len != 0) { + vm_map_lock(&vmspace->vm_map); + rv = vm_map_insert(&vmspace->vm_map, NULL, 0, + map_addr, map_addr + map_len, + VM_PROT_ALL, VM_PROT_ALL, 0); + vm_map_unlock(&vmspace->vm_map); + if (rv != KERN_SUCCESS) + return EINVAL; + } + + if (copy_len != 0) { + vm_object_reference(object); + rv = vm_map_find(exec_map, + object, + trunc_page(offset + filsz), + &data_buf, + PAGE_SIZE, + TRUE, + VM_PROT_READ, + VM_PROT_ALL, + MAP_COPY_ON_WRITE | MAP_COPY_NEEDED); + if (rv != KERN_SUCCESS) { + vm_object_deallocate(object); + return EINVAL; + } + pmap_object_init_pt(exec_map->pmap, data_buf, object, + (vm_pindex_t) OFF_TO_IDX(trunc_page(offset + filsz)), + PAGE_SIZE, 1); + + /* send the page fragment to user space */ + error = copyout((caddr_t)data_buf, (caddr_t)map_addr, copy_len); + vm_map_remove(exec_map, data_buf, data_buf + PAGE_SIZE); + if (error) + return (error); + } + + /* + * set it to the specified protection + */ + vm_map_protect(&vmspace->vm_map, map_addr, map_addr + map_len, prot, + FALSE); + + return error; +} + +static int +elf_load_file(struct proc *p, char *file, u_long *addr, u_long *entry) +{ + Elf_Ehdr *hdr = NULL; + Elf_Phdr *phdr = NULL; + struct nameidata nd; + struct vmspace *vmspace = p->p_vmspace; + struct vattr attr; + struct image_params image_params, *imgp; + vm_prot_t prot; + unsigned long text_size = 0, data_size = 0; + unsigned long text_addr = 0, data_addr = 0; + int error, i; + + imgp = &image_params; + /* + * Initialize part of the common data + */ + imgp->proc = p; + imgp->uap = NULL; + imgp->attr = &attr; + imgp->firstpage = NULL; + imgp->image_header = (char *)kmem_alloc_wait(exec_map, PAGE_SIZE); + + if (imgp->image_header == NULL) { + nd.ni_vp = NULL; + error = ENOMEM; + goto fail; + } + + NDINIT(&nd, LOOKUP, LOCKLEAF|FOLLOW, UIO_SYSSPACE, file, p); + + if (error = namei(&nd)) { + nd.ni_vp = NULL; + goto fail; + } + + imgp->vp = nd.ni_vp; + + /* + * Check permissions, modes, uid, etc on the file, and "open" it. + */ + error = exec_check_permissions(imgp); + if (error) { + VOP_UNLOCK(nd.ni_vp, 0, p); + goto fail; + } + + error = exec_map_first_page(imgp); + VOP_UNLOCK(nd.ni_vp, 0, p); + if (error) + goto fail; + + hdr = (Elf_Ehdr *)imgp->image_header; + if (error = elf_check_header(hdr, ET_DYN)) + goto fail; + + /* Only support headers that fit within first page for now */ + if ((hdr->e_phoff > PAGE_SIZE) || + (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { + error = ENOEXEC; + goto fail; + } + + phdr = (Elf_Phdr *)(imgp->image_header + hdr->e_phoff); + + for (i = 0; i < hdr->e_phnum; i++) { + if (phdr[i].p_type == PT_LOAD) { /* Loadable segment */ + prot = 0; + if (phdr[i].p_flags & PF_X) + prot |= VM_PROT_EXECUTE; + if (phdr[i].p_flags & PF_W) + prot |= VM_PROT_WRITE; + if (phdr[i].p_flags & PF_R) + prot |= VM_PROT_READ; + + if (error = elf_load_section(p, vmspace, nd.ni_vp, + phdr[i].p_offset, + (caddr_t)phdr[i].p_vaddr + + (*addr), + phdr[i].p_memsz, + phdr[i].p_filesz, prot)) + goto fail; + + /* + * Is this .text or .data ?? + * + * We only handle one each of those yet XXX + */ + if (hdr->e_entry >= phdr[i].p_vaddr && + hdr->e_entry <(phdr[i].p_vaddr+phdr[i].p_memsz)) { + text_addr = trunc_page(phdr[i].p_vaddr+(*addr)); + text_size = round_page(phdr[i].p_memsz + + phdr[i].p_vaddr - + trunc_page(phdr[i].p_vaddr)); + *entry=(unsigned long)hdr->e_entry+(*addr); + } else { + data_addr = trunc_page(phdr[i].p_vaddr+(*addr)); + data_size = round_page(phdr[i].p_memsz + + phdr[i].p_vaddr - + trunc_page(phdr[i].p_vaddr)); + } + } + } + +fail: + if (imgp->firstpage) + exec_unmap_first_page(imgp); + if (imgp->image_header) + kmem_free_wakeup(exec_map, (vm_offset_t)imgp->image_header, + PAGE_SIZE); + if (nd.ni_vp) + vrele(nd.ni_vp); + + return error; +} + +static int +exec_elf_imgact(struct image_params *imgp) +{ + const Elf_Ehdr *hdr = (const Elf_Ehdr *) imgp->image_header; + const Elf_Phdr *phdr; + Elf_Auxargs *elf_auxargs = NULL; + struct vmspace *vmspace; + vm_prot_t prot; + u_long text_size = 0, data_size = 0; + u_long text_addr = 0, data_addr = 0; + u_long addr, entry = 0, proghdr = 0; + int error, i; + const char *interp = NULL; + Elf_Brandinfo *brand_info; + char *brand; + char path[MAXPATHLEN]; + + /* + * Do we have a valid ELF header ? + */ + if (elf_check_header(hdr, ET_EXEC)) + return -1; + + /* + * From here on down, we return an errno, not -1, as we've + * detected an ELF file. + */ + + if ((hdr->e_phoff > PAGE_SIZE) || + (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { + /* Only support headers in first page for now */ + return ENOEXEC; + } + phdr = (const Elf_Phdr*)(imgp->image_header + hdr->e_phoff); + + /* + * From this point on, we may have resources that need to be freed. + */ + if (error = exec_extract_strings(imgp)) + goto fail; + + exec_new_vmspace(imgp); + + vmspace = imgp->proc->p_vmspace; + + for (i = 0; i < hdr->e_phnum; i++) { + switch(phdr[i].p_type) { + + case PT_LOAD: /* Loadable segment */ + prot = 0; + if (phdr[i].p_flags & PF_X) + prot |= VM_PROT_EXECUTE; + if (phdr[i].p_flags & PF_W) + prot |= VM_PROT_WRITE; + if (phdr[i].p_flags & PF_R) + prot |= VM_PROT_READ; + + if (error = elf_load_section(imgp->proc, + vmspace, imgp->vp, + phdr[i].p_offset, + (caddr_t)phdr[i].p_vaddr, + phdr[i].p_memsz, + phdr[i].p_filesz, prot)) + goto fail; + + /* + * Is this .text or .data ?? + * + * We only handle one each of those yet XXX + */ + if (hdr->e_entry >= phdr[i].p_vaddr && + hdr->e_entry <(phdr[i].p_vaddr+phdr[i].p_memsz)) { + text_addr = trunc_page(phdr[i].p_vaddr); + text_size = round_page(phdr[i].p_memsz + + phdr[i].p_vaddr - + text_addr); + entry = (u_long)hdr->e_entry; + } else { + data_addr = trunc_page(phdr[i].p_vaddr); + data_size = round_page(phdr[i].p_memsz + + phdr[i].p_vaddr - + data_addr); + } + break; + case PT_INTERP: /* Path to interpreter */ + if (phdr[i].p_filesz > MAXPATHLEN || + phdr[i].p_offset + phdr[i].p_filesz > PAGE_SIZE) { + error = ENOEXEC; + goto fail; + } + interp = imgp->image_header + phdr[i].p_offset; + break; + case PT_PHDR: /* Program header table info */ + proghdr = phdr[i].p_vaddr; + break; + default: + break; + } + } + + vmspace->vm_tsize = text_size >> PAGE_SHIFT; + vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; + vmspace->vm_dsize = data_size >> PAGE_SHIFT; + vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; + + addr = 2L*MAXDSIZ; /* May depend on OS type XXX */ + + imgp->entry_addr = entry; + + /* If the executable has a brand, search for it in the brand list. */ + brand_info = NULL; + brand = (char *)&hdr->e_ident[EI_BRAND]; + if (brand[0] != '\0') { + for (i = 0; i < MAX_BRANDS; i++) { + Elf_Brandinfo *bi = elf_brand_list[i]; + + if (bi != NULL && strcmp(brand, bi->brand) == 0) { + brand_info = bi; + break; + } + } + } + + /* Lacking a known brand, search for a recognized interpreter. */ + if (brand_info == NULL && interp != NULL) { + for (i = 0; i < MAX_BRANDS; i++) { + Elf_Brandinfo *bi = elf_brand_list[i]; + + if (bi != NULL && + strcmp(interp, bi->interp_path) == 0) { + brand_info = bi; + break; + } + } + } + +#ifdef __alpha__ + /* XXX - Assume FreeBSD on the alpha. */ + if (brand_info == NULL) + brand_info = &freebsd_brand_info; +#endif + + if (brand_info == NULL) { + if (brand[0] == 0) + uprintf("ELF binary type not known." + " Use \"brandelf\" to brand it.\n"); + else + uprintf("ELF binary type \"%.*s\" not known.\n", + EI_NIDENT - EI_BRAND, brand); + error = ENOEXEC; + goto fail; + } + + imgp->proc->p_sysent = brand_info->sysvec; + if (interp != NULL) { + snprintf(path, sizeof(path), "%s%s", + brand_info->emul_path, interp); + if ((error = elf_load_file(imgp->proc, path, &addr, + &imgp->entry_addr)) != 0) { + uprintf("ELF interpreter %s not found\n", path); + goto fail; + } + } + + /* + * Construct auxargs table (used by the fixup routine) + */ + elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); + elf_auxargs->execfd = -1; + elf_auxargs->phdr = proghdr; + elf_auxargs->phent = hdr->e_phentsize; + elf_auxargs->phnum = hdr->e_phnum; + elf_auxargs->pagesz = PAGE_SIZE; + elf_auxargs->base = addr; + elf_auxargs->flags = 0; + elf_auxargs->entry = entry; + elf_auxargs->trace = elf_trace; + + imgp->auxargs = elf_auxargs; + imgp->interpreted = 0; + + /* don't allow modifying the file while we run it */ + imgp->vp->v_flag |= VTEXT; + +fail: + return error; +} + +static int +elf_freebsd_fixup(long **stack_base, struct image_params *imgp) +{ + Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; + long *pos; + + pos = *stack_base + (imgp->argc + imgp->envc + 2); + + if (args->trace) { + AUXARGS_ENTRY(pos, AT_DEBUG, 1); + } + if (args->execfd != -1) { + AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); + } + AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); + AUXARGS_ENTRY(pos, AT_PHENT, args->phent); + AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); + AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); + AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); + AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); + AUXARGS_ENTRY(pos, AT_BASE, args->base); + AUXARGS_ENTRY(pos, AT_NULL, 0); + + free(imgp->auxargs, M_TEMP); + imgp->auxargs = NULL; + + (*stack_base)--; + suword(*stack_base, (long) imgp->argc); + return 0; +} + +/* + * Code for generating ELF core dumps. + */ + +typedef void (*segment_callback) __P((vm_map_entry_t, void *)); + +/* Closure for cb_put_phdr(). */ +struct phdr_closure { + Elf_Phdr *phdr; /* Program header to fill in */ + Elf_Off offset; /* Offset of segment in core file */ +}; + +/* Closure for cb_size_segment(). */ +struct sseg_closure { + int count; /* Count of writable segments. */ + size_t size; /* Total size of all writable segments. */ +}; + +static void cb_put_phdr __P((vm_map_entry_t, void *)); +static void cb_size_segment __P((vm_map_entry_t, void *)); +static void each_writable_segment __P((struct proc *, segment_callback, + void *)); +static int elf_corehdr __P((struct proc *, struct vnode *, struct ucred *, + int, void *, size_t)); +static void elf_puthdr __P((struct proc *, void *, size_t *, + const prstatus_t *, const prfpregset_t *, const prpsinfo_t *, int)); +static void elf_putnote __P((void *, size_t *, const char *, int, + const void *, size_t)); + +extern int osreldate; + +int +elf_coredump(p) + register struct proc *p; +{ + register struct vnode *vp; + register struct ucred *cred = p->p_cred->pc_ucred; + struct nameidata nd; + struct vattr vattr; + int error, error1; + char *name; /* name of corefile */ + struct sseg_closure seginfo; + void *hdr; + size_t hdrsize; + + STOPEVENT(p, S_CORE, 0); + + if (sugid_coredump == 0 && p->p_flag & P_SUGID) + return (EFAULT); + + /* Size the program segments. */ + seginfo.count = 0; + seginfo.size = 0; + each_writable_segment(p, cb_size_segment, &seginfo); + + /* + * Calculate the size of the core file header area by making + * a dry run of generating it. Nothing is written, but the + * size is calculated. + */ + hdrsize = 0; + elf_puthdr((struct proc *)NULL, (void *)NULL, &hdrsize, + (const prstatus_t *)NULL, (const prfpregset_t *)NULL, + (const prpsinfo_t *)NULL, seginfo.count); + + if (hdrsize + seginfo.size >= p->p_rlimit[RLIMIT_CORE].rlim_cur) + return (EFAULT); + name = expand_name(p->p_comm, p->p_ucred->cr_uid, p->p_pid); + if (name == NULL) + return (EFAULT); /* XXX -- not the best error */ + + NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, name, p); + error = vn_open(&nd, O_CREAT | FWRITE, S_IRUSR | S_IWUSR); + free(name, M_TEMP); + if (error) + return (error); + vp = nd.ni_vp; + + /* Don't dump to non-regular files or files with links. */ + if (vp->v_type != VREG || + VOP_GETATTR(vp, &vattr, cred, p) || vattr.va_nlink != 1) { + error = EFAULT; + goto out; + } + VATTR_NULL(&vattr); + vattr.va_size = 0; + VOP_LEASE(vp, p, cred, LEASE_WRITE); + VOP_SETATTR(vp, &vattr, cred, p); + p->p_acflag |= ACORE; + + + /* + * Allocate memory for building the header, fill it up, + * and write it out. + */ + hdr = malloc(hdrsize, M_TEMP, M_WAITOK); + if (hdr == NULL) { + error = EINVAL; + goto out; + } + error = elf_corehdr(p, vp, cred, seginfo.count, hdr, hdrsize); + + /* Write the contents of all of the writable segments. */ + if (error == 0) { + Elf_Phdr *php; + off_t offset; + int i; + + php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1; + offset = hdrsize; + for (i = 0; i < seginfo.count; i++) { + error = vn_rdwr(UIO_WRITE, vp, (caddr_t)php->p_vaddr, + php->p_filesz, offset, UIO_USERSPACE, + IO_NODELOCKED|IO_UNIT, cred, (int *)NULL, p); + if (error != 0) + break; + offset += php->p_filesz; + php++; + } + } + free(hdr, M_TEMP); + +out: + VOP_UNLOCK(vp, 0, p); + error1 = vn_close(vp, FWRITE, cred, p); + if (error == 0) + error = error1; + return (error); +} + +/* + * A callback for each_writable_segment() to write out the segment's + * program header entry. + */ +static void +cb_put_phdr(entry, closure) + vm_map_entry_t entry; + void *closure; +{ + struct phdr_closure *phc = (struct phdr_closure *)closure; + Elf_Phdr *phdr = phc->phdr; + + phc->offset = round_page(phc->offset); + + phdr->p_type = PT_LOAD; + phdr->p_offset = phc->offset; + phdr->p_vaddr = entry->start; + phdr->p_paddr = 0; + phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; + phdr->p_align = PAGE_SIZE; + phdr->p_flags = 0; + if (entry->protection & VM_PROT_READ) + phdr->p_flags |= PF_R; + if (entry->protection & VM_PROT_WRITE) + phdr->p_flags |= PF_W; + if (entry->protection & VM_PROT_EXECUTE) + phdr->p_flags |= PF_X; + + phc->offset += phdr->p_filesz; + phc->phdr++; +} + +/* + * A callback for each_writable_segment() to gather information about + * the number of segments and their total size. + */ +static void +cb_size_segment(entry, closure) + vm_map_entry_t entry; + void *closure; +{ + struct sseg_closure *ssc = (struct sseg_closure *)closure; + + ssc->count++; + ssc->size += entry->end - entry->start; +} + +/* + * For each writable segment in the process's memory map, call the given + * function with a pointer to the map entry and some arbitrary + * caller-supplied data. + */ +static void +each_writable_segment(p, func, closure) + struct proc *p; + segment_callback func; + void *closure; +{ + vm_map_t map = &p->p_vmspace->vm_map; + vm_map_entry_t entry; + + for (entry = map->header.next; entry != &map->header; + entry = entry->next) { + vm_object_t obj; + + if (entry->eflags & (MAP_ENTRY_IS_A_MAP|MAP_ENTRY_IS_SUB_MAP) || + (entry->protection & (VM_PROT_READ|VM_PROT_WRITE)) != + (VM_PROT_READ|VM_PROT_WRITE)) + continue; + + if ((obj = entry->object.vm_object) == NULL) + continue; + + /* Find the deepest backing object. */ + while (obj->backing_object != NULL) + obj = obj->backing_object; + + /* Ignore memory-mapped devices and such things. */ + if (obj->type != OBJT_DEFAULT && + obj->type != OBJT_SWAP && + obj->type != OBJT_VNODE) + continue; + + (*func)(entry, closure); + } +} + +/* + * Write the core file header to the file, including padding up to + * the page boundary. + */ +static int +elf_corehdr(p, vp, cred, numsegs, hdr, hdrsize) + struct proc *p; + struct vnode *vp; + struct ucred *cred; + int numsegs; + size_t hdrsize; + void *hdr; +{ + size_t off; + prstatus_t status; + prfpregset_t fpregset; + prpsinfo_t psinfo; + + /* Gather the information for the header. */ + bzero(&status, sizeof status); + status.pr_version = PRSTATUS_VERSION; + status.pr_statussz = sizeof(prstatus_t); + status.pr_gregsetsz = sizeof(gregset_t); + status.pr_fpregsetsz = sizeof(fpregset_t); + status.pr_osreldate = osreldate; +#ifndef COMPAT_LINUX_THREADS + status.pr_cursig = p->p_sigacts->ps_sig; +#else + status.pr_cursig = p->p_sig; +#endif /* COMPAT_LINUX_THREADS */ + status.pr_pid = p->p_pid; + fill_regs(p, &status.pr_reg); + + fill_fpregs(p, &fpregset); + + bzero(&psinfo, sizeof psinfo); + psinfo.pr_version = PRPSINFO_VERSION; + psinfo.pr_psinfosz = sizeof(prpsinfo_t); + strncpy(psinfo.pr_fname, p->p_comm, MAXCOMLEN); + /* XXX - We don't fill in the command line arguments properly yet. */ + strncpy(psinfo.pr_psargs, p->p_comm, PRARGSZ); + + /* Fill in the header. */ + bzero(hdr, hdrsize); + off = 0; + elf_puthdr(p, hdr, &off, &status, &fpregset, &psinfo, numsegs); + + /* Write it to the core file. */ + return vn_rdwr(UIO_WRITE, vp, hdr, hdrsize, (off_t)0, + UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, cred, NULL, p); +} + +static void +elf_puthdr(struct proc *p, void *dst, size_t *off, const prstatus_t *status, + const prfpregset_t *fpregset, const prpsinfo_t *psinfo, int numsegs) +{ + size_t ehoff; + size_t phoff; + size_t noteoff; + size_t notesz; + + ehoff = *off; + *off += sizeof(Elf_Ehdr); + + phoff = *off; + *off += (numsegs + 1) * sizeof(Elf_Phdr); + + noteoff = *off; + elf_putnote(dst, off, "FreeBSD", NT_PRSTATUS, status, + sizeof *status); + elf_putnote(dst, off, "FreeBSD", NT_FPREGSET, fpregset, + sizeof *fpregset); + elf_putnote(dst, off, "FreeBSD", NT_PRPSINFO, psinfo, + sizeof *psinfo); + notesz = *off - noteoff; + + /* Align up to a page boundary for the program segments. */ + *off = round_page(*off); + + if (dst != NULL) { + Elf_Ehdr *ehdr; + Elf_Phdr *phdr; + struct phdr_closure phc; + + /* + * Fill in the ELF header. + */ + ehdr = (Elf_Ehdr *)((char *)dst + ehoff); + ehdr->e_ident[EI_MAG0] = ELFMAG0; + ehdr->e_ident[EI_MAG1] = ELFMAG1; + ehdr->e_ident[EI_MAG2] = ELFMAG2; + ehdr->e_ident[EI_MAG3] = ELFMAG3; + ehdr->e_ident[EI_CLASS] = ELF_CLASS; + ehdr->e_ident[EI_DATA] = ELF_DATA; + ehdr->e_ident[EI_VERSION] = EV_CURRENT; + ehdr->e_ident[EI_PAD] = 0; + strncpy(ehdr->e_ident + EI_BRAND, "FreeBSD", + EI_NIDENT - EI_BRAND); + ehdr->e_type = ET_CORE; + ehdr->e_machine = ELF_ARCH; + ehdr->e_version = EV_CURRENT; + ehdr->e_entry = 0; + ehdr->e_phoff = phoff; + ehdr->e_flags = 0; + ehdr->e_ehsize = sizeof(Elf_Ehdr); + ehdr->e_phentsize = sizeof(Elf_Phdr); + ehdr->e_phnum = numsegs + 1; + ehdr->e_shentsize = sizeof(Elf_Shdr); + ehdr->e_shnum = 0; + ehdr->e_shstrndx = SHN_UNDEF; + + /* + * Fill in the program header entries. + */ + phdr = (Elf_Phdr *)((char *)dst + phoff); + + /* The note segement. */ + phdr->p_type = PT_NOTE; + phdr->p_offset = noteoff; + phdr->p_vaddr = 0; + phdr->p_paddr = 0; + phdr->p_filesz = notesz; + phdr->p_memsz = 0; + phdr->p_flags = 0; + phdr->p_align = 0; + phdr++; + + /* All the writable segments from the program. */ + phc.phdr = phdr; + phc.offset = *off; + each_writable_segment(p, cb_put_phdr, &phc); + } +} + +static void +elf_putnote(void *dst, size_t *off, const char *name, int type, + const void *desc, size_t descsz) +{ + Elf_Note note; + + note.n_namesz = strlen(name) + 1; + note.n_descsz = descsz; + note.n_type = type; + if (dst != NULL) + bcopy(¬e, (char *)dst + *off, sizeof note); + *off += sizeof note; + if (dst != NULL) + bcopy(name, (char *)dst + *off, note.n_namesz); + *off += roundup2(note.n_namesz, sizeof(Elf_Size)); + if (dst != NULL) + bcopy(desc, (char *)dst + *off, note.n_descsz); + *off += roundup2(note.n_descsz, sizeof(Elf_Size)); +} + +/* + * Tell kern_execve.c about it, with a little help from the linker. + * Since `const' objects end up in the text segment, TEXT_SET is the + * correct directive to use. + */ +static const struct execsw elf_execsw = {exec_elf_imgact, "ELF"}; +EXEC_SET(elf, elf_execsw); 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