freebsd-skq/stand/common/load_elf.c
Dimitry Andric 6e26189be4 Fix loader detection of vbefb support on !amd64
On i386, after 6c7a932d0b, the vbefb vt
driver was no longer detected by the loader, if any kernel module was
loaded after the kernel itself.

This was caused by the parse_vt_drv_set() function being called multiple
times, resetting the detection flag. (It was called multiple times,
becuase i386 .ko files are shared objects like the kernel proper, while
this is not the case on amd64.)

Fix this by skipping the set_vt_drv_set lookup if vbefb was already
detected.

Reviewed by:	tsoome
2021-01-27 22:28:43 +01:00

1323 lines
33 KiB
C

/*-
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* Copyright (c) 1998 Peter Wemm <peter@freebsd.org>
* 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.
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/endian.h>
#include <sys/exec.h>
#include <sys/linker.h>
#include <sys/module.h>
#include <sys/stdint.h>
#include <string.h>
#include <machine/elf.h>
#include <stand.h>
#define FREEBSD_ELF
#include <sys/link_elf.h>
#include <gfx_fb.h>
#include "bootstrap.h"
#define COPYOUT(s,d,l) archsw.arch_copyout((vm_offset_t)(s), d, l)
#if defined(__i386__) && __ELF_WORD_SIZE == 64
#undef ELF_TARG_CLASS
#undef ELF_TARG_MACH
#define ELF_TARG_CLASS ELFCLASS64
#define ELF_TARG_MACH EM_X86_64
#endif
typedef struct elf_file {
Elf_Phdr *ph;
Elf_Ehdr *ehdr;
Elf_Sym *symtab;
Elf_Hashelt *hashtab;
Elf_Hashelt nbuckets;
Elf_Hashelt nchains;
Elf_Hashelt *buckets;
Elf_Hashelt *chains;
Elf_Rel *rel;
size_t relsz;
Elf_Rela *rela;
size_t relasz;
char *strtab;
size_t strsz;
int fd;
caddr_t firstpage;
size_t firstlen;
int kernel;
uint64_t off;
#ifdef LOADER_VERIEXEC_VECTX
struct vectx *vctx;
#endif
} *elf_file_t;
#ifdef LOADER_VERIEXEC_VECTX
#define VECTX_HANDLE(ef) (ef)->vctx
#else
#define VECTX_HANDLE(ef) (ef)->fd
#endif
static int __elfN(loadimage)(struct preloaded_file *mp, elf_file_t ef,
uint64_t loadaddr);
static int __elfN(lookup_symbol)(elf_file_t ef, const char* name,
Elf_Sym *sym, unsigned char type);
static int __elfN(reloc_ptr)(struct preloaded_file *mp, elf_file_t ef,
Elf_Addr p, void *val, size_t len);
static int __elfN(parse_modmetadata)(struct preloaded_file *mp, elf_file_t ef,
Elf_Addr p_start, Elf_Addr p_end);
static bool __elfN(parse_vt_drv_set)(struct preloaded_file *mp, elf_file_t ef,
Elf_Addr p_start, Elf_Addr p_end);
static symaddr_fn __elfN(symaddr);
static char *fake_modname(const char *name);
const char *__elfN(kerneltype) = "elf kernel";
const char *__elfN(moduletype) = "elf module";
uint64_t __elfN(relocation_offset) = 0;
extern void elf_wrong_field_size(void);
#define CONVERT_FIELD(b, f, e) \
switch (sizeof((b)->f)) { \
case 2: \
(b)->f = e ## 16toh((b)->f); \
break; \
case 4: \
(b)->f = e ## 32toh((b)->f); \
break; \
case 8: \
(b)->f = e ## 64toh((b)->f); \
break; \
default: \
/* Force a link time error. */ \
elf_wrong_field_size(); \
break; \
}
#define CONVERT_SWITCH(h, d, f) \
switch ((h)->e_ident[EI_DATA]) { \
case ELFDATA2MSB: \
f(d, be); \
break; \
case ELFDATA2LSB: \
f(d, le); \
break; \
default: \
return (EINVAL); \
}
static int elf_header_convert(Elf_Ehdr *ehdr)
{
/*
* Fixup ELF header endianness.
*
* The Xhdr structure was loaded using block read call to optimize file
* accesses. It might happen, that the endianness of the system memory
* is different that endianness of the ELF header. Swap fields here to
* guarantee that Xhdr always contain valid data regardless of
* architecture.
*/
#define HEADER_FIELDS(b, e) \
CONVERT_FIELD(b, e_type, e); \
CONVERT_FIELD(b, e_machine, e); \
CONVERT_FIELD(b, e_version, e); \
CONVERT_FIELD(b, e_entry, e); \
CONVERT_FIELD(b, e_phoff, e); \
CONVERT_FIELD(b, e_shoff, e); \
CONVERT_FIELD(b, e_flags, e); \
CONVERT_FIELD(b, e_ehsize, e); \
CONVERT_FIELD(b, e_phentsize, e); \
CONVERT_FIELD(b, e_phnum, e); \
CONVERT_FIELD(b, e_shentsize, e); \
CONVERT_FIELD(b, e_shnum, e); \
CONVERT_FIELD(b, e_shstrndx, e)
CONVERT_SWITCH(ehdr, ehdr, HEADER_FIELDS);
#undef HEADER_FIELDS
return (0);
}
static int elf_program_header_convert(const Elf_Ehdr *ehdr, Elf_Phdr *phdr)
{
#define PROGRAM_HEADER_FIELDS(b, e) \
CONVERT_FIELD(b, p_type, e); \
CONVERT_FIELD(b, p_flags, e); \
CONVERT_FIELD(b, p_offset, e); \
CONVERT_FIELD(b, p_vaddr, e); \
CONVERT_FIELD(b, p_paddr, e); \
CONVERT_FIELD(b, p_filesz, e); \
CONVERT_FIELD(b, p_memsz, e); \
CONVERT_FIELD(b, p_align, e)
CONVERT_SWITCH(ehdr, phdr, PROGRAM_HEADER_FIELDS);
#undef PROGRAM_HEADER_FIELDS
return (0);
}
static int elf_section_header_convert(const Elf_Ehdr *ehdr, Elf_Shdr *shdr)
{
#define SECTION_HEADER_FIELDS(b, e) \
CONVERT_FIELD(b, sh_name, e); \
CONVERT_FIELD(b, sh_type, e); \
CONVERT_FIELD(b, sh_link, e); \
CONVERT_FIELD(b, sh_info, e); \
CONVERT_FIELD(b, sh_flags, e); \
CONVERT_FIELD(b, sh_addr, e); \
CONVERT_FIELD(b, sh_offset, e); \
CONVERT_FIELD(b, sh_size, e); \
CONVERT_FIELD(b, sh_addralign, e); \
CONVERT_FIELD(b, sh_entsize, e)
CONVERT_SWITCH(ehdr, shdr, SECTION_HEADER_FIELDS);
#undef SECTION_HEADER_FIELDS
return (0);
}
#undef CONVERT_SWITCH
#undef CONVERT_FIELD
static int
__elfN(load_elf_header)(char *filename, elf_file_t ef)
{
ssize_t bytes_read;
Elf_Ehdr *ehdr;
int err;
/*
* Open the image, read and validate the ELF header
*/
if (filename == NULL) /* can't handle nameless */
return (EFTYPE);
if ((ef->fd = open(filename, O_RDONLY)) == -1)
return (errno);
ef->firstpage = malloc(PAGE_SIZE);
if (ef->firstpage == NULL) {
close(ef->fd);
return (ENOMEM);
}
#ifdef LOADER_VERIEXEC_VECTX
{
int verror;
ef->vctx = vectx_open(ef->fd, filename, 0L, NULL, &verror, __func__);
if (verror) {
printf("Unverified %s: %s\n", filename, ve_error_get());
close(ef->fd);
free(ef->vctx);
return (EAUTH);
}
}
#endif
bytes_read = VECTX_READ(VECTX_HANDLE(ef), ef->firstpage, PAGE_SIZE);
ef->firstlen = (size_t)bytes_read;
if (bytes_read < 0 || ef->firstlen <= sizeof(Elf_Ehdr)) {
err = EFTYPE; /* could be EIO, but may be small file */
goto error;
}
ehdr = ef->ehdr = (Elf_Ehdr *)ef->firstpage;
/* Is it ELF? */
if (!IS_ELF(*ehdr)) {
err = EFTYPE;
goto error;
}
if (ehdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || /* Layout ? */
ehdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
ehdr->e_ident[EI_VERSION] != EV_CURRENT) /* Version ? */ {
err = EFTYPE;
goto error;
}
err = elf_header_convert(ehdr);
if (err)
goto error;
if (ehdr->e_version != EV_CURRENT || ehdr->e_machine != ELF_TARG_MACH) {
/* Machine ? */
err = EFTYPE;
goto error;
}
#if defined(LOADER_VERIEXEC) && !defined(LOADER_VERIEXEC_VECTX)
if (verify_file(ef->fd, filename, bytes_read, VE_MUST, __func__) < 0) {
err = EAUTH;
goto error;
}
#endif
return (0);
error:
if (ef->firstpage != NULL) {
free(ef->firstpage);
ef->firstpage = NULL;
}
if (ef->fd != -1) {
#ifdef LOADER_VERIEXEC_VECTX
free(ef->vctx);
#endif
close(ef->fd);
ef->fd = -1;
}
return (err);
}
/*
* Attempt to load the file (file) as an ELF module. It will be stored at
* (dest), and a pointer to a module structure describing the loaded object
* will be saved in (result).
*/
int
__elfN(loadfile)(char *filename, uint64_t dest, struct preloaded_file **result)
{
return (__elfN(loadfile_raw)(filename, dest, result, 0));
}
int
__elfN(loadfile_raw)(char *filename, uint64_t dest,
struct preloaded_file **result, int multiboot)
{
struct preloaded_file *fp, *kfp;
struct elf_file ef;
Elf_Ehdr *ehdr;
int err;
fp = NULL;
bzero(&ef, sizeof(struct elf_file));
ef.fd = -1;
err = __elfN(load_elf_header)(filename, &ef);
if (err != 0)
return (err);
ehdr = ef.ehdr;
/*
* Check to see what sort of module we are.
*/
kfp = file_findfile(NULL, __elfN(kerneltype));
#ifdef __powerpc__
/*
* Kernels can be ET_DYN, so just assume the first loaded object is the
* kernel. This assumption will be checked later.
*/
if (kfp == NULL)
ef.kernel = 1;
#endif
if (ef.kernel || ehdr->e_type == ET_EXEC) {
/* Looks like a kernel */
if (kfp != NULL) {
printf("elf" __XSTRING(__ELF_WORD_SIZE)
"_loadfile: kernel already loaded\n");
err = EPERM;
goto oerr;
}
/*
* Calculate destination address based on kernel entrypoint.
*
* For ARM, the destination address is independent of any values
* in the elf header (an ARM kernel can be loaded at any 2MB
* boundary), so we leave dest set to the value calculated by
* archsw.arch_loadaddr() and passed in to this function.
*/
#ifndef __arm__
if (ehdr->e_type == ET_EXEC)
dest = (ehdr->e_entry & ~PAGE_MASK);
#endif
if ((ehdr->e_entry & ~PAGE_MASK) == 0) {
printf("elf" __XSTRING(__ELF_WORD_SIZE)
"_loadfile: not a kernel (maybe static binary?)\n");
err = EPERM;
goto oerr;
}
ef.kernel = 1;
} else if (ehdr->e_type == ET_DYN) {
/* Looks like a kld module */
if (multiboot != 0) {
printf("elf" __XSTRING(__ELF_WORD_SIZE)
"_loadfile: can't load module as multiboot\n");
err = EPERM;
goto oerr;
}
if (kfp == NULL) {
printf("elf" __XSTRING(__ELF_WORD_SIZE)
"_loadfile: can't load module before kernel\n");
err = EPERM;
goto oerr;
}
if (strcmp(__elfN(kerneltype), kfp->f_type)) {
printf("elf" __XSTRING(__ELF_WORD_SIZE)
"_loadfile: can't load module with kernel type '%s'\n",
kfp->f_type);
err = EPERM;
goto oerr;
}
/* Looks OK, got ahead */
ef.kernel = 0;
} else {
err = EFTYPE;
goto oerr;
}
if (archsw.arch_loadaddr != NULL)
dest = archsw.arch_loadaddr(LOAD_ELF, ehdr, dest);
else
dest = roundup(dest, PAGE_SIZE);
/*
* Ok, we think we should handle this.
*/
fp = file_alloc();
if (fp == NULL) {
printf("elf" __XSTRING(__ELF_WORD_SIZE)
"_loadfile: cannot allocate module info\n");
err = EPERM;
goto out;
}
if (ef.kernel == 1 && multiboot == 0)
setenv("kernelname", filename, 1);
fp->f_name = strdup(filename);
if (multiboot == 0)
fp->f_type = strdup(ef.kernel ?
__elfN(kerneltype) : __elfN(moduletype));
else
fp->f_type = strdup("elf multiboot kernel");
#ifdef ELF_VERBOSE
if (ef.kernel)
printf("%s entry at 0x%jx\n", filename,
(uintmax_t)ehdr->e_entry);
#else
printf("%s ", filename);
#endif
fp->f_size = __elfN(loadimage)(fp, &ef, dest);
if (fp->f_size == 0 || fp->f_addr == 0)
goto ioerr;
/* save exec header as metadata */
file_addmetadata(fp, MODINFOMD_ELFHDR, sizeof(*ehdr), ehdr);
/* Load OK, return module pointer */
*result = (struct preloaded_file *)fp;
err = 0;
goto out;
ioerr:
err = EIO;
oerr:
file_discard(fp);
out:
if (ef.firstpage)
free(ef.firstpage);
if (ef.fd != -1) {
#ifdef LOADER_VERIEXEC_VECTX
if (!err && ef.vctx) {
int verror;
verror = vectx_close(ef.vctx, VE_MUST, __func__);
if (verror) {
err = EAUTH;
file_discard(fp);
}
}
#endif
close(ef.fd);
}
return (err);
}
/*
* With the file (fd) open on the image, and (ehdr) containing
* the Elf header, load the image at (off)
*/
static int
__elfN(loadimage)(struct preloaded_file *fp, elf_file_t ef, uint64_t off)
{
int i;
u_int j;
Elf_Ehdr *ehdr;
Elf_Phdr *phdr, *php;
Elf_Shdr *shdr;
char *shstr;
int ret;
vm_offset_t firstaddr;
vm_offset_t lastaddr;
size_t chunk;
ssize_t result;
Elf_Addr ssym, esym;
Elf_Dyn *dp;
Elf_Addr adp;
Elf_Addr ctors;
int ndp;
int symstrindex;
int symtabindex;
Elf_Size size;
u_int fpcopy;
Elf_Sym sym;
Elf_Addr p_start, p_end;
dp = NULL;
shdr = NULL;
ret = 0;
firstaddr = lastaddr = 0;
ehdr = ef->ehdr;
#ifdef __powerpc__
if (ef->kernel) {
#else
if (ehdr->e_type == ET_EXEC) {
#endif
#if defined(__i386__) || defined(__amd64__)
#if __ELF_WORD_SIZE == 64
/* x86_64 relocates after locore */
off = - (off & 0xffffffffff000000ull);
#else
/* i386 relocates after locore */
off = - (off & 0xff000000u);
#endif
#elif defined(__powerpc__)
/*
* On the purely virtual memory machines like e500, the kernel
* is linked against its final VA range, which is most often
* not available at the loader stage, but only after kernel
* initializes and completes its VM settings. In such cases we
* cannot use p_vaddr field directly to load ELF segments, but
* put them at some 'load-time' locations.
*/
if (off & 0xf0000000u) {
off = -(off & 0xf0000000u);
/*
* XXX the physical load address should not be
* hardcoded. Note that the Book-E kernel assumes that
* it's loaded at a 16MB boundary for now...
*/
off += 0x01000000;
}
ehdr->e_entry += off;
#ifdef ELF_VERBOSE
printf("Converted entry 0x%jx\n", (uintmax_t)ehdr->e_entry);
#endif
#elif defined(__arm__) && !defined(EFI)
/*
* The elf headers in arm kernels specify virtual addresses in
* all header fields, even the ones that should be physical
* addresses. We assume the entry point is in the first page,
* and masking the page offset will leave us with the virtual
* address the kernel was linked at. We subtract that from the
* load offset, making 'off' into the value which, when added
* to a virtual address in an elf header, translates it to a
* physical address. We do the va->pa conversion on the entry
* point address in the header now, so that later we can launch
* the kernel by just jumping to that address.
*
* When booting from UEFI the copyin and copyout functions
* handle adjusting the location relative to the first virtual
* address. Because of this there is no need to adjust the
* offset or entry point address as these will both be handled
* by the efi code.
*/
off -= ehdr->e_entry & ~PAGE_MASK;
ehdr->e_entry += off;
#ifdef ELF_VERBOSE
printf("ehdr->e_entry 0x%jx, va<->pa off %llx\n",
(uintmax_t)ehdr->e_entry, off);
#endif
#else
off = 0; /* other archs use direct mapped kernels */
#endif
}
ef->off = off;
if (ef->kernel)
__elfN(relocation_offset) = off;
if ((ehdr->e_phoff + ehdr->e_phnum * sizeof(*phdr)) > ef->firstlen) {
printf("elf" __XSTRING(__ELF_WORD_SIZE)
"_loadimage: program header not within first page\n");
goto out;
}
phdr = (Elf_Phdr *)(ef->firstpage + ehdr->e_phoff);
for (i = 0; i < ehdr->e_phnum; i++) {
if (elf_program_header_convert(ehdr, phdr))
continue;
/* We want to load PT_LOAD segments only.. */
if (phdr[i].p_type != PT_LOAD)
continue;
#ifdef ELF_VERBOSE
printf("Segment: 0x%lx@0x%lx -> 0x%lx-0x%lx",
(long)phdr[i].p_filesz, (long)phdr[i].p_offset,
(long)(phdr[i].p_vaddr + off),
(long)(phdr[i].p_vaddr + off + phdr[i].p_memsz - 1));
#else
if ((phdr[i].p_flags & PF_W) == 0) {
printf("text=0x%lx ", (long)phdr[i].p_filesz);
} else {
printf("data=0x%lx", (long)phdr[i].p_filesz);
if (phdr[i].p_filesz < phdr[i].p_memsz)
printf("+0x%lx", (long)(phdr[i].p_memsz -
phdr[i].p_filesz));
printf(" ");
}
#endif
fpcopy = 0;
if (ef->firstlen > phdr[i].p_offset) {
fpcopy = ef->firstlen - phdr[i].p_offset;
archsw.arch_copyin(ef->firstpage + phdr[i].p_offset,
phdr[i].p_vaddr + off, fpcopy);
}
if (phdr[i].p_filesz > fpcopy) {
if (kern_pread(VECTX_HANDLE(ef),
phdr[i].p_vaddr + off + fpcopy,
phdr[i].p_filesz - fpcopy,
phdr[i].p_offset + fpcopy) != 0) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"_loadimage: read failed\n");
goto out;
}
}
/* clear space from oversized segments; eg: bss */
if (phdr[i].p_filesz < phdr[i].p_memsz) {
#ifdef ELF_VERBOSE
printf(" (bss: 0x%lx-0x%lx)",
(long)(phdr[i].p_vaddr + off + phdr[i].p_filesz),
(long)(phdr[i].p_vaddr + off + phdr[i].p_memsz -1));
#endif
kern_bzero(phdr[i].p_vaddr + off + phdr[i].p_filesz,
phdr[i].p_memsz - phdr[i].p_filesz);
}
#ifdef ELF_VERBOSE
printf("\n");
#endif
if (archsw.arch_loadseg != NULL)
archsw.arch_loadseg(ehdr, phdr + i, off);
if (firstaddr == 0 || firstaddr > (phdr[i].p_vaddr + off))
firstaddr = phdr[i].p_vaddr + off;
if (lastaddr == 0 || lastaddr <
(phdr[i].p_vaddr + off + phdr[i].p_memsz))
lastaddr = phdr[i].p_vaddr + off + phdr[i].p_memsz;
}
lastaddr = roundup(lastaddr, sizeof(long));
/*
* Get the section headers. We need this for finding the .ctors
* section as well as for loading any symbols. Both may be hard
* to do if reading from a .gz file as it involves seeking. I
* think the rule is going to have to be that you must strip a
* file to remove symbols before gzipping it.
*/
chunk = (size_t)ehdr->e_shnum * (size_t)ehdr->e_shentsize;
if (chunk == 0 || ehdr->e_shoff == 0)
goto nosyms;
shdr = alloc_pread(VECTX_HANDLE(ef), ehdr->e_shoff, chunk);
if (shdr == NULL) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"_loadimage: failed to read section headers");
goto nosyms;
}
for (i = 0; i < ehdr->e_shnum; i++)
elf_section_header_convert(ehdr, &shdr[i]);
file_addmetadata(fp, MODINFOMD_SHDR, chunk, shdr);
/*
* Read the section string table and look for the .ctors section.
* We need to tell the kernel where it is so that it can call the
* ctors.
*/
chunk = shdr[ehdr->e_shstrndx].sh_size;
if (chunk) {
shstr = alloc_pread(VECTX_HANDLE(ef),
shdr[ehdr->e_shstrndx].sh_offset, chunk);
if (shstr) {
for (i = 0; i < ehdr->e_shnum; i++) {
if (strcmp(shstr + shdr[i].sh_name,
".ctors") != 0)
continue;
ctors = shdr[i].sh_addr;
file_addmetadata(fp, MODINFOMD_CTORS_ADDR,
sizeof(ctors), &ctors);
size = shdr[i].sh_size;
file_addmetadata(fp, MODINFOMD_CTORS_SIZE,
sizeof(size), &size);
break;
}
free(shstr);
}
}
/*
* Now load any symbols.
*/
symtabindex = -1;
symstrindex = -1;
for (i = 0; i < ehdr->e_shnum; i++) {
if (shdr[i].sh_type != SHT_SYMTAB)
continue;
for (j = 0; j < ehdr->e_phnum; j++) {
if (phdr[j].p_type != PT_LOAD)
continue;
if (shdr[i].sh_offset >= phdr[j].p_offset &&
(shdr[i].sh_offset + shdr[i].sh_size <=
phdr[j].p_offset + phdr[j].p_filesz)) {
shdr[i].sh_offset = 0;
shdr[i].sh_size = 0;
break;
}
}
if (shdr[i].sh_offset == 0 || shdr[i].sh_size == 0)
continue; /* alread loaded in a PT_LOAD above */
/* Save it for loading below */
symtabindex = i;
symstrindex = shdr[i].sh_link;
}
if (symtabindex < 0 || symstrindex < 0)
goto nosyms;
/* Ok, committed to a load. */
#ifndef ELF_VERBOSE
printf("syms=[");
#endif
ssym = lastaddr;
for (i = symtabindex; i >= 0; i = symstrindex) {
#ifdef ELF_VERBOSE
char *secname;
switch(shdr[i].sh_type) {
case SHT_SYMTAB: /* Symbol table */
secname = "symtab";
break;
case SHT_STRTAB: /* String table */
secname = "strtab";
break;
default:
secname = "WHOA!!";
break;
}
#endif
size = shdr[i].sh_size;
#if defined(__powerpc__)
#if __ELF_WORD_SIZE == 64
size = htobe64(size);
#else
size = htobe32(size);
#endif
#endif
archsw.arch_copyin(&size, lastaddr, sizeof(size));
lastaddr += sizeof(size);
#ifdef ELF_VERBOSE
printf("\n%s: 0x%jx@0x%jx -> 0x%jx-0x%jx", secname,
(uintmax_t)shdr[i].sh_size, (uintmax_t)shdr[i].sh_offset,
(uintmax_t)lastaddr,
(uintmax_t)(lastaddr + shdr[i].sh_size));
#else
if (i == symstrindex)
printf("+");
printf("0x%lx+0x%lx", (long)sizeof(size), (long)size);
#endif
if (VECTX_LSEEK(VECTX_HANDLE(ef), (off_t)shdr[i].sh_offset, SEEK_SET) == -1) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"_loadimage: could not seek for symbols - skipped!");
lastaddr = ssym;
ssym = 0;
goto nosyms;
}
result = archsw.arch_readin(VECTX_HANDLE(ef), lastaddr, shdr[i].sh_size);
if (result < 0 || (size_t)result != shdr[i].sh_size) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"_loadimage: could not read symbols - skipped! "
"(%ju != %ju)", (uintmax_t)result,
(uintmax_t)shdr[i].sh_size);
lastaddr = ssym;
ssym = 0;
goto nosyms;
}
/* Reset offsets relative to ssym */
lastaddr += shdr[i].sh_size;
lastaddr = roundup(lastaddr, sizeof(size));
if (i == symtabindex)
symtabindex = -1;
else if (i == symstrindex)
symstrindex = -1;
}
esym = lastaddr;
#ifndef ELF_VERBOSE
printf("]");
#endif
#if defined(__powerpc__)
/* On PowerPC we always need to provide BE data to the kernel */
#if __ELF_WORD_SIZE == 64
ssym = htobe64((uint64_t)ssym);
esym = htobe64((uint64_t)esym);
#else
ssym = htobe32((uint32_t)ssym);
esym = htobe32((uint32_t)esym);
#endif
#endif
file_addmetadata(fp, MODINFOMD_SSYM, sizeof(ssym), &ssym);
file_addmetadata(fp, MODINFOMD_ESYM, sizeof(esym), &esym);
nosyms:
printf("\n");
ret = lastaddr - firstaddr;
fp->f_addr = firstaddr;
php = NULL;
for (i = 0; i < ehdr->e_phnum; i++) {
if (phdr[i].p_type == PT_DYNAMIC) {
php = phdr + i;
adp = php->p_vaddr;
file_addmetadata(fp, MODINFOMD_DYNAMIC, sizeof(adp),
&adp);
break;
}
}
if (php == NULL) /* this is bad, we cannot get to symbols or _DYNAMIC */
goto out;
ndp = php->p_filesz / sizeof(Elf_Dyn);
if (ndp == 0)
goto out;
dp = malloc(php->p_filesz);
if (dp == NULL)
goto out;
archsw.arch_copyout(php->p_vaddr + off, dp, php->p_filesz);
ef->strsz = 0;
for (i = 0; i < ndp; i++) {
if (dp[i].d_tag == 0)
break;
switch (dp[i].d_tag) {
case DT_HASH:
ef->hashtab =
(Elf_Hashelt*)(uintptr_t)(dp[i].d_un.d_ptr + off);
break;
case DT_STRTAB:
ef->strtab =
(char *)(uintptr_t)(dp[i].d_un.d_ptr + off);
break;
case DT_STRSZ:
ef->strsz = dp[i].d_un.d_val;
break;
case DT_SYMTAB:
ef->symtab =
(Elf_Sym *)(uintptr_t)(dp[i].d_un.d_ptr + off);
break;
case DT_REL:
ef->rel =
(Elf_Rel *)(uintptr_t)(dp[i].d_un.d_ptr + off);
break;
case DT_RELSZ:
ef->relsz = dp[i].d_un.d_val;
break;
case DT_RELA:
ef->rela =
(Elf_Rela *)(uintptr_t)(dp[i].d_un.d_ptr + off);
break;
case DT_RELASZ:
ef->relasz = dp[i].d_un.d_val;
break;
default:
break;
}
}
if (ef->hashtab == NULL || ef->symtab == NULL ||
ef->strtab == NULL || ef->strsz == 0)
goto out;
COPYOUT(ef->hashtab, &ef->nbuckets, sizeof(ef->nbuckets));
COPYOUT(ef->hashtab + 1, &ef->nchains, sizeof(ef->nchains));
ef->buckets = ef->hashtab + 2;
ef->chains = ef->buckets + ef->nbuckets;
if (!gfx_state.tg_kernel_supported &&
__elfN(lookup_symbol)(ef, "__start_set_vt_drv_set", &sym,
STT_NOTYPE) == 0) {
p_start = sym.st_value + ef->off;
if (__elfN(lookup_symbol)(ef, "__stop_set_vt_drv_set", &sym,
STT_NOTYPE) == 0) {
p_end = sym.st_value + ef->off;
gfx_state.tg_kernel_supported =
__elfN(parse_vt_drv_set)(fp, ef, p_start, p_end);
}
}
if (__elfN(lookup_symbol)(ef, "__start_set_modmetadata_set", &sym,
STT_NOTYPE) != 0)
return 0;
p_start = sym.st_value + ef->off;
if (__elfN(lookup_symbol)(ef, "__stop_set_modmetadata_set", &sym,
STT_NOTYPE) != 0)
return ENOENT;
p_end = sym.st_value + ef->off;
if (__elfN(parse_modmetadata)(fp, ef, p_start, p_end) == 0)
goto out;
if (ef->kernel) /* kernel must not depend on anything */
goto out;
out:
if (dp)
free(dp);
if (shdr)
free(shdr);
return ret;
}
static char invalid_name[] = "bad";
char *
fake_modname(const char *name)
{
const char *sp, *ep;
char *fp;
size_t len;
sp = strrchr(name, '/');
if (sp)
sp++;
else
sp = name;
ep = strrchr(sp, '.');
if (ep == NULL) {
ep = sp + strlen(sp);
}
if (ep == sp) {
sp = invalid_name;
ep = invalid_name + sizeof(invalid_name) - 1;
}
len = ep - sp;
fp = malloc(len + 1);
if (fp == NULL)
return NULL;
memcpy(fp, sp, len);
fp[len] = '\0';
return fp;
}
#if (defined(__i386__) || defined(__powerpc__)) && __ELF_WORD_SIZE == 64
struct mod_metadata64 {
int md_version; /* structure version MDTV_* */
int md_type; /* type of entry MDT_* */
uint64_t md_data; /* specific data */
uint64_t md_cval; /* common string label */
};
#endif
#if defined(__amd64__) && __ELF_WORD_SIZE == 32
struct mod_metadata32 {
int md_version; /* structure version MDTV_* */
int md_type; /* type of entry MDT_* */
uint32_t md_data; /* specific data */
uint32_t md_cval; /* common string label */
};
#endif
int
__elfN(load_modmetadata)(struct preloaded_file *fp, uint64_t dest)
{
struct elf_file ef;
int err, i, j;
Elf_Shdr *sh_meta, *shdr = NULL;
Elf_Shdr *sh_data[2];
char *shstrtab = NULL;
size_t size;
Elf_Addr p_start, p_end;
bzero(&ef, sizeof(struct elf_file));
ef.fd = -1;
err = __elfN(load_elf_header)(fp->f_name, &ef);
if (err != 0)
goto out;
if (ef.kernel == 1 || ef.ehdr->e_type == ET_EXEC) {
ef.kernel = 1;
} else if (ef.ehdr->e_type != ET_DYN) {
err = EFTYPE;
goto out;
}
size = (size_t)ef.ehdr->e_shnum * (size_t)ef.ehdr->e_shentsize;
shdr = alloc_pread(VECTX_HANDLE(&ef), ef.ehdr->e_shoff, size);
if (shdr == NULL) {
err = ENOMEM;
goto out;
}
/* Load shstrtab. */
shstrtab = alloc_pread(VECTX_HANDLE(&ef), shdr[ef.ehdr->e_shstrndx].sh_offset,
shdr[ef.ehdr->e_shstrndx].sh_size);
if (shstrtab == NULL) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"load_modmetadata: unable to load shstrtab\n");
err = EFTYPE;
goto out;
}
/* Find set_modmetadata_set and data sections. */
sh_data[0] = sh_data[1] = sh_meta = NULL;
for (i = 0, j = 0; i < ef.ehdr->e_shnum; i++) {
if (strcmp(&shstrtab[shdr[i].sh_name],
"set_modmetadata_set") == 0) {
sh_meta = &shdr[i];
}
if ((strcmp(&shstrtab[shdr[i].sh_name], ".data") == 0) ||
(strcmp(&shstrtab[shdr[i].sh_name], ".rodata") == 0)) {
sh_data[j++] = &shdr[i];
}
}
if (sh_meta == NULL || sh_data[0] == NULL || sh_data[1] == NULL) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"load_modmetadata: unable to find set_modmetadata_set or data sections\n");
err = EFTYPE;
goto out;
}
/* Load set_modmetadata_set into memory */
err = kern_pread(VECTX_HANDLE(&ef), dest, sh_meta->sh_size, sh_meta->sh_offset);
if (err != 0) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"load_modmetadata: unable to load set_modmetadata_set: %d\n", err);
goto out;
}
p_start = dest;
p_end = dest + sh_meta->sh_size;
dest += sh_meta->sh_size;
/* Load data sections into memory. */
err = kern_pread(VECTX_HANDLE(&ef), dest, sh_data[0]->sh_size,
sh_data[0]->sh_offset);
if (err != 0) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"load_modmetadata: unable to load data: %d\n", err);
goto out;
}
/*
* We have to increment the dest, so that the offset is the same into
* both the .rodata and .data sections.
*/
ef.off = -(sh_data[0]->sh_addr - dest);
dest += (sh_data[1]->sh_addr - sh_data[0]->sh_addr);
err = kern_pread(VECTX_HANDLE(&ef), dest, sh_data[1]->sh_size,
sh_data[1]->sh_offset);
if (err != 0) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"load_modmetadata: unable to load data: %d\n", err);
goto out;
}
err = __elfN(parse_modmetadata)(fp, &ef, p_start, p_end);
if (err != 0) {
printf("\nelf" __XSTRING(__ELF_WORD_SIZE)
"load_modmetadata: unable to parse metadata: %d\n", err);
goto out;
}
out:
if (shstrtab != NULL)
free(shstrtab);
if (shdr != NULL)
free(shdr);
if (ef.firstpage != NULL)
free(ef.firstpage);
if (ef.fd != -1) {
#ifdef LOADER_VERIEXEC_VECTX
if (!err && ef.vctx) {
int verror;
verror = vectx_close(ef.vctx, VE_MUST, __func__);
if (verror) {
err = EAUTH;
file_discard(fp);
}
}
#endif
close(ef.fd);
}
return (err);
}
/*
* Walk through vt_drv_set, each vt driver structure starts with
* static 16 chars for driver name. If we have "vbefb", return true.
*/
static bool
__elfN(parse_vt_drv_set)(struct preloaded_file *fp, elf_file_t ef,
Elf_Addr p_start, Elf_Addr p_end)
{
Elf_Addr v, p;
char vd_name[16];
int error;
p = p_start;
while (p < p_end) {
COPYOUT(p, &v, sizeof(v));
error = __elfN(reloc_ptr)(fp, ef, p, &v, sizeof(v));
if (error == EOPNOTSUPP)
v += ef->off;
else if (error != 0)
return (false);
COPYOUT(v, &vd_name, sizeof(vd_name));
if (strncmp(vd_name, "vbefb", sizeof(vd_name)) == 0)
return (true);
p += sizeof(Elf_Addr);
}
return (false);
}
int
__elfN(parse_modmetadata)(struct preloaded_file *fp, elf_file_t ef,
Elf_Addr p_start, Elf_Addr p_end)
{
struct mod_metadata md;
#if (defined(__i386__) || defined(__powerpc__)) && __ELF_WORD_SIZE == 64
struct mod_metadata64 md64;
#elif defined(__amd64__) && __ELF_WORD_SIZE == 32
struct mod_metadata32 md32;
#endif
struct mod_depend *mdepend;
struct mod_version mver;
char *s;
int error, modcnt, minfolen;
Elf_Addr v, p;
modcnt = 0;
p = p_start;
while (p < p_end) {
COPYOUT(p, &v, sizeof(v));
error = __elfN(reloc_ptr)(fp, ef, p, &v, sizeof(v));
if (error == EOPNOTSUPP)
v += ef->off;
else if (error != 0)
return (error);
#if (defined(__i386__) || defined(__powerpc__)) && __ELF_WORD_SIZE == 64
COPYOUT(v, &md64, sizeof(md64));
error = __elfN(reloc_ptr)(fp, ef, v, &md64, sizeof(md64));
if (error == EOPNOTSUPP) {
md64.md_cval += ef->off;
md64.md_data += ef->off;
} else if (error != 0)
return (error);
md.md_version = md64.md_version;
md.md_type = md64.md_type;
md.md_cval = (const char *)(uintptr_t)md64.md_cval;
md.md_data = (void *)(uintptr_t)md64.md_data;
#elif defined(__amd64__) && __ELF_WORD_SIZE == 32
COPYOUT(v, &md32, sizeof(md32));
error = __elfN(reloc_ptr)(fp, ef, v, &md32, sizeof(md32));
if (error == EOPNOTSUPP) {
md32.md_cval += ef->off;
md32.md_data += ef->off;
} else if (error != 0)
return (error);
md.md_version = md32.md_version;
md.md_type = md32.md_type;
md.md_cval = (const char *)(uintptr_t)md32.md_cval;
md.md_data = (void *)(uintptr_t)md32.md_data;
#else
COPYOUT(v, &md, sizeof(md));
error = __elfN(reloc_ptr)(fp, ef, v, &md, sizeof(md));
if (error == EOPNOTSUPP) {
md.md_cval += ef->off;
md.md_data = (void *)((uintptr_t)md.md_data +
(uintptr_t)ef->off);
} else if (error != 0)
return (error);
#endif
p += sizeof(Elf_Addr);
switch(md.md_type) {
case MDT_DEPEND:
if (ef->kernel) /* kernel must not depend on anything */
break;
s = strdupout((vm_offset_t)md.md_cval);
minfolen = sizeof(*mdepend) + strlen(s) + 1;
mdepend = malloc(minfolen);
if (mdepend == NULL)
return ENOMEM;
COPYOUT((vm_offset_t)md.md_data, mdepend,
sizeof(*mdepend));
strcpy((char*)(mdepend + 1), s);
free(s);
file_addmetadata(fp, MODINFOMD_DEPLIST, minfolen,
mdepend);
free(mdepend);
break;
case MDT_VERSION:
s = strdupout((vm_offset_t)md.md_cval);
COPYOUT((vm_offset_t)md.md_data, &mver, sizeof(mver));
file_addmodule(fp, s, mver.mv_version, NULL);
free(s);
modcnt++;
break;
}
}
if (modcnt == 0) {
s = fake_modname(fp->f_name);
file_addmodule(fp, s, 1, NULL);
free(s);
}
return 0;
}
static unsigned long
elf_hash(const char *name)
{
const unsigned char *p = (const unsigned char *) name;
unsigned long h = 0;
unsigned long g;
while (*p != '\0') {
h = (h << 4) + *p++;
if ((g = h & 0xf0000000) != 0)
h ^= g >> 24;
h &= ~g;
}
return h;
}
static const char __elfN(bad_symtable)[] = "elf" __XSTRING(__ELF_WORD_SIZE)
"_lookup_symbol: corrupt symbol table\n";
int
__elfN(lookup_symbol)(elf_file_t ef, const char* name, Elf_Sym *symp,
unsigned char type)
{
Elf_Hashelt symnum;
Elf_Sym sym;
char *strp;
unsigned long hash;
hash = elf_hash(name);
COPYOUT(&ef->buckets[hash % ef->nbuckets], &symnum, sizeof(symnum));
while (symnum != STN_UNDEF) {
if (symnum >= ef->nchains) {
printf(__elfN(bad_symtable));
return ENOENT;
}
COPYOUT(ef->symtab + symnum, &sym, sizeof(sym));
if (sym.st_name == 0) {
printf(__elfN(bad_symtable));
return ENOENT;
}
strp = strdupout((vm_offset_t)(ef->strtab + sym.st_name));
if (strcmp(name, strp) == 0) {
free(strp);
if (sym.st_shndx != SHN_UNDEF ||
(sym.st_value != 0 &&
ELF_ST_TYPE(sym.st_info) == type)) {
*symp = sym;
return 0;
}
return ENOENT;
}
free(strp);
COPYOUT(&ef->chains[symnum], &symnum, sizeof(symnum));
}
return ENOENT;
}
/*
* Apply any intra-module relocations to the value. p is the load address
* of the value and val/len is the value to be modified. This does NOT modify
* the image in-place, because this is done by kern_linker later on.
*
* Returns EOPNOTSUPP if no relocation method is supplied.
*/
static int
__elfN(reloc_ptr)(struct preloaded_file *mp, elf_file_t ef,
Elf_Addr p, void *val, size_t len)
{
size_t n;
Elf_Rela a;
Elf_Rel r;
int error;
/*
* The kernel is already relocated, but we still want to apply
* offset adjustments.
*/
if (ef->kernel)
return (EOPNOTSUPP);
for (n = 0; n < ef->relsz / sizeof(r); n++) {
COPYOUT(ef->rel + n, &r, sizeof(r));
error = __elfN(reloc)(ef, __elfN(symaddr), &r, ELF_RELOC_REL,
ef->off, p, val, len);
if (error != 0)
return (error);
}
for (n = 0; n < ef->relasz / sizeof(a); n++) {
COPYOUT(ef->rela + n, &a, sizeof(a));
error = __elfN(reloc)(ef, __elfN(symaddr), &a, ELF_RELOC_RELA,
ef->off, p, val, len);
if (error != 0)
return (error);
}
return (0);
}
static Elf_Addr
__elfN(symaddr)(struct elf_file *ef, Elf_Size symidx)
{
/* Symbol lookup by index not required here. */
return (0);
}