bFLT loader (for uClinux binaries).

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@1951 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
pbrook 2006-06-11 13:32:59 +00:00
parent ac62f715c6
commit e5fe0c5230
8 changed files with 1147 additions and 272 deletions

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@ -171,7 +171,12 @@ LDFLAGS+=-p
main.o: CFLAGS+=-p main.o: CFLAGS+=-p
endif endif
OBJS= elfload.o main.o syscall.o mmap.o signal.o path.o osdep.o thunk.o OBJS= main.o syscall.o mmap.o signal.o path.o osdep.o thunk.o \
elfload.o linuxload.o
ifdef TARGET_HAS_BFLT
OBJS+= flatload.o
endif
ifeq ($(TARGET_ARCH), i386) ifeq ($(TARGET_ARCH), i386)
OBJS+= vm86.o OBJS+= vm86.o
endif endif

6
configure vendored
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@ -773,6 +773,7 @@ echo "/* Automatically generated by configure - do not modify */" > $config_h
echo "include ../config-host.mak" >> $config_mak echo "include ../config-host.mak" >> $config_mak
echo "#include \"../config-host.h\"" >> $config_h echo "#include \"../config-host.h\"" >> $config_h
bflt="no"
interp_prefix1=`echo "$interp_prefix" | sed "s/%M/$target_cpu/g"` interp_prefix1=`echo "$interp_prefix" | sed "s/%M/$target_cpu/g"`
echo "#define CONFIG_QEMU_PREFIX \"$interp_prefix1\"" >> $config_h echo "#define CONFIG_QEMU_PREFIX \"$interp_prefix1\"" >> $config_h
@ -787,6 +788,7 @@ elif test "$target_cpu" = "arm" -o "$target_cpu" = "armeb" ; then
echo "TARGET_ARCH=arm" >> $config_mak echo "TARGET_ARCH=arm" >> $config_mak
echo "#define TARGET_ARCH \"arm\"" >> $config_h echo "#define TARGET_ARCH \"arm\"" >> $config_h
echo "#define TARGET_ARM 1" >> $config_h echo "#define TARGET_ARM 1" >> $config_h
bflt="yes"
elif test "$target_cpu" = "sparc" ; then elif test "$target_cpu" = "sparc" ; then
echo "TARGET_ARCH=sparc" >> $config_mak echo "TARGET_ARCH=sparc" >> $config_mak
echo "#define TARGET_ARCH \"sparc\"" >> $config_h echo "#define TARGET_ARCH \"sparc\"" >> $config_h
@ -842,6 +844,10 @@ if test "$target_cpu" = "arm" -o "$target_cpu" = "armeb" ; then
echo "CONFIG_SOFTFLOAT=yes" >> $config_mak echo "CONFIG_SOFTFLOAT=yes" >> $config_mak
echo "#define CONFIG_SOFTFLOAT 1" >> $config_h echo "#define CONFIG_SOFTFLOAT 1" >> $config_h
fi fi
if test "$target_user_only" = "yes" -a "$bflt" = "yes"; then
echo "TARGET_HAS_BFLT=yes" >> $config_mak
echo "#define TARGET_HAS_BFLT 1" >> $config_h
fi
# sdl defines # sdl defines
if test "$target_user_only" = "no"; then if test "$target_user_only" = "no"; then

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@ -3,7 +3,6 @@
#include <stdio.h> #include <stdio.h>
#include <sys/types.h> #include <sys/types.h>
#include <fcntl.h> #include <fcntl.h>
#include <sys/stat.h>
#include <errno.h> #include <errno.h>
#include <unistd.h> #include <unistd.h>
#include <sys/mman.h> #include <sys/mman.h>
@ -59,6 +58,11 @@ static uint32_t get_elf_hwcap(void)
#define ELF_DATA ELFDATA2LSB #define ELF_DATA ELFDATA2LSB
#define ELF_ARCH EM_386 #define ELF_ARCH EM_386
static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)
{
regs->esp = infop->start_stack;
regs->eip = infop->entry;
/* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program /* SVR4/i386 ABI (pages 3-31, 3-32) says that when the program
starts %edx contains a pointer to a function which might be starts %edx contains a pointer to a function which might be
registered using `atexit'. This provides a mean for the registered using `atexit'. This provides a mean for the
@ -66,12 +70,7 @@ static uint32_t get_elf_hwcap(void)
that have been loaded before the code runs. that have been loaded before the code runs.
A value of 0 tells we have no such handler. */ A value of 0 tells we have no such handler. */
#define ELF_PLAT_INIT(_r) _r->edx = 0 regs->edx = 0;
static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)
{
regs->esp = infop->start_stack;
regs->eip = infop->entry;
} }
#define USE_ELF_CORE_DUMP #define USE_ELF_CORE_DUMP
@ -93,8 +92,6 @@ static inline void init_thread(struct target_pt_regs *regs, struct image_info *i
#endif #endif
#define ELF_ARCH EM_ARM #define ELF_ARCH EM_ARM
#define ELF_PLAT_INIT(_r) _r->ARM_r0 = 0
static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop) static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)
{ {
target_long stack = infop->start_stack; target_long stack = infop->start_stack;
@ -107,7 +104,9 @@ static inline void init_thread(struct target_pt_regs *regs, struct image_info *i
regs->ARM_r2 = tgetl(stack + 8); /* envp */ regs->ARM_r2 = tgetl(stack + 8); /* envp */
regs->ARM_r1 = tgetl(stack + 4); /* envp */ regs->ARM_r1 = tgetl(stack + 4); /* envp */
/* XXX: it seems that r0 is zeroed after ! */ /* XXX: it seems that r0 is zeroed after ! */
// regs->ARM_r0 = tgetl(stack); /* argc */ regs->ARM_r0 = 0;
/* For uClinux PIC binaries. */
regs->ARM_r10 = infop->start_data;
} }
#define USE_ELF_CORE_DUMP #define USE_ELF_CORE_DUMP
@ -142,9 +141,6 @@ enum
#define ELF_DATA ELFDATA2MSB #define ELF_DATA ELFDATA2MSB
#define ELF_ARCH EM_SPARC #define ELF_ARCH EM_SPARC
/*XXX*/
#define ELF_PLAT_INIT(_r)
static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop) static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)
{ {
regs->tstate = 0; regs->tstate = 0;
@ -163,9 +159,6 @@ static inline void init_thread(struct target_pt_regs *regs, struct image_info *i
#define ELF_DATA ELFDATA2MSB #define ELF_DATA ELFDATA2MSB
#define ELF_ARCH EM_SPARC #define ELF_ARCH EM_SPARC
/*XXX*/
#define ELF_PLAT_INIT(_r)
static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop) static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)
{ {
regs->psr = 0; regs->psr = 0;
@ -192,20 +185,6 @@ static inline void init_thread(struct target_pt_regs *regs, struct image_info *i
#endif #endif
#define ELF_ARCH EM_PPC #define ELF_ARCH EM_PPC
/* Note that isn't exactly what regular kernel does
* but this is what the ABI wants and is needed to allow
* execution of PPC BSD programs.
*/
#define ELF_PLAT_INIT(_r) \
do { \
target_ulong *pos = (target_ulong *)bprm->p, tmp = 1; \
_r->gpr[3] = bprm->argc; \
_r->gpr[4] = (unsigned long)++pos; \
for (; tmp != 0; pos++) \
tmp = ldl(pos); \
_r->gpr[5] = (unsigned long)pos; \
} while (0)
/* /*
* We need to put in some extra aux table entries to tell glibc what * We need to put in some extra aux table entries to tell glibc what
* the cache block size is, so it can use the dcbz instruction safely. * the cache block size is, so it can use the dcbz instruction safely.
@ -239,9 +218,22 @@ do { \
static inline void init_thread(struct target_pt_regs *_regs, struct image_info *infop) static inline void init_thread(struct target_pt_regs *_regs, struct image_info *infop)
{ {
target_ulong pos = infop->start_stack;
target_ulong tmp;
_regs->msr = 1 << MSR_PR; /* Set user mode */ _regs->msr = 1 << MSR_PR; /* Set user mode */
_regs->gpr[1] = infop->start_stack; _regs->gpr[1] = infop->start_stack;
_regs->nip = infop->entry; _regs->nip = infop->entry;
/* Note that isn't exactly what regular kernel does
* but this is what the ABI wants and is needed to allow
* execution of PPC BSD programs.
*/
_regs->gpr[3] = tgetl(pos);
pos += sizeof(target_ulong);
_regs->gpr[4] = pos;
for (tmp = 1; tmp != 0; pos += sizeof(target_ulong))
tmp = ldl(pos);
_regs->gpr[5] = pos;
} }
#define USE_ELF_CORE_DUMP #define USE_ELF_CORE_DUMP
@ -263,8 +255,6 @@ static inline void init_thread(struct target_pt_regs *_regs, struct image_info *
#endif #endif
#define ELF_ARCH EM_MIPS #define ELF_ARCH EM_MIPS
#define ELF_PLAT_INIT(_r)
static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop) static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)
{ {
regs->cp0_status = CP0St_UM; regs->cp0_status = CP0St_UM;
@ -284,8 +274,6 @@ static inline void init_thread(struct target_pt_regs *regs, struct image_info *i
#define ELF_DATA ELFDATA2LSB #define ELF_DATA ELFDATA2LSB
#define ELF_ARCH EM_SH #define ELF_ARCH EM_SH
#define ELF_PLAT_INIT(_r) /* XXXXX */
static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop) static inline void init_thread(struct target_pt_regs *regs, struct image_info *infop)
{ {
/* Check other registers XXXXX */ /* Check other registers XXXXX */
@ -308,30 +296,6 @@ static inline void init_thread(struct target_pt_regs *regs, struct image_info *i
#include "elf.h" #include "elf.h"
/*
* MAX_ARG_PAGES defines the number of pages allocated for arguments
* and envelope for the new program. 32 should suffice, this gives
* a maximum env+arg of 128kB w/4KB pages!
*/
#define MAX_ARG_PAGES 32
/*
* This structure is used to hold the arguments that are
* used when loading binaries.
*/
struct linux_binprm {
char buf[128];
void *page[MAX_ARG_PAGES];
unsigned long p;
int sh_bang;
int fd;
int e_uid, e_gid;
int argc, envc;
char * filename; /* Name of binary */
unsigned long loader, exec;
int dont_iput; /* binfmt handler has put inode */
};
struct exec struct exec
{ {
unsigned int a_info; /* Use macros N_MAGIC, etc for access */ unsigned int a_info; /* Use macros N_MAGIC, etc for access */
@ -377,8 +341,6 @@ struct exec
#define PER_XENIX (0x0007 | STICKY_TIMEOUTS) #define PER_XENIX (0x0007 | STICKY_TIMEOUTS)
/* Necessary parameters */ /* Necessary parameters */
#define NGROUPS 32
#define TARGET_ELF_EXEC_PAGESIZE TARGET_PAGE_SIZE #define TARGET_ELF_EXEC_PAGESIZE TARGET_PAGE_SIZE
#define TARGET_ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(TARGET_ELF_EXEC_PAGESIZE-1)) #define TARGET_ELF_PAGESTART(_v) ((_v) & ~(unsigned long)(TARGET_ELF_EXEC_PAGESIZE-1))
#define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE-1)) #define TARGET_ELF_PAGEOFFSET(_v) ((_v) & (TARGET_ELF_EXEC_PAGESIZE-1))
@ -452,12 +414,12 @@ static void bswap_sym(Elf32_Sym *sym)
#endif #endif
/* /*
* 'copy_string()' copies argument/envelope strings from user * 'copy_elf_strings()' copies argument/envelope strings from user
* memory to free pages in kernel mem. These are in a format ready * memory to free pages in kernel mem. These are in a format ready
* to be put directly into the top of new user memory. * to be put directly into the top of new user memory.
* *
*/ */
static unsigned long copy_strings(int argc,char ** argv, void **page, static unsigned long copy_elf_strings(int argc,char ** argv, void **page,
unsigned long p) unsigned long p)
{ {
char *tmp, *tmp1, *pag = NULL; char *tmp, *tmp1, *pag = NULL;
@ -506,101 +468,6 @@ static unsigned long copy_strings(int argc,char ** argv, void **page,
return p; return p;
} }
static int in_group_p(gid_t g)
{
/* return TRUE if we're in the specified group, FALSE otherwise */
int ngroup;
int i;
gid_t grouplist[NGROUPS];
ngroup = getgroups(NGROUPS, grouplist);
for(i = 0; i < ngroup; i++) {
if(grouplist[i] == g) {
return 1;
}
}
return 0;
}
static int count(char ** vec)
{
int i;
for(i = 0; *vec; i++) {
vec++;
}
return(i);
}
static int prepare_binprm(struct linux_binprm *bprm)
{
struct stat st;
int mode;
int retval, id_change;
if(fstat(bprm->fd, &st) < 0) {
return(-errno);
}
mode = st.st_mode;
if(!S_ISREG(mode)) { /* Must be regular file */
return(-EACCES);
}
if(!(mode & 0111)) { /* Must have at least one execute bit set */
return(-EACCES);
}
bprm->e_uid = geteuid();
bprm->e_gid = getegid();
id_change = 0;
/* Set-uid? */
if(mode & S_ISUID) {
bprm->e_uid = st.st_uid;
if(bprm->e_uid != geteuid()) {
id_change = 1;
}
}
/* Set-gid? */
/*
* If setgid is set but no group execute bit then this
* is a candidate for mandatory locking, not a setgid
* executable.
*/
if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
bprm->e_gid = st.st_gid;
if (!in_group_p(bprm->e_gid)) {
id_change = 1;
}
}
memset(bprm->buf, 0, sizeof(bprm->buf));
retval = lseek(bprm->fd, 0L, SEEK_SET);
if(retval >= 0) {
retval = read(bprm->fd, bprm->buf, 128);
}
if(retval < 0) {
perror("prepare_binprm");
exit(-1);
/* return(-errno); */
}
else {
return(retval);
}
}
static inline void memcpy_to_target(target_ulong dest, const void *src,
unsigned long len)
{
void *host_ptr;
host_ptr = lock_user(dest, len, 0);
memcpy(host_ptr, src, len);
unlock_user(host_ptr, dest, 1);
}
unsigned long setup_arg_pages(target_ulong p, struct linux_binprm * bprm, unsigned long setup_arg_pages(target_ulong p, struct linux_binprm * bprm,
struct image_info * info) struct image_info * info)
{ {
@ -628,11 +495,6 @@ unsigned long setup_arg_pages(target_ulong p, struct linux_binprm * bprm,
stack_base = error + size - MAX_ARG_PAGES*TARGET_PAGE_SIZE; stack_base = error + size - MAX_ARG_PAGES*TARGET_PAGE_SIZE;
p += stack_base; p += stack_base;
if (bprm->loader) {
bprm->loader += stack_base;
}
bprm->exec += stack_base;
for (i = 0 ; i < MAX_ARG_PAGES ; i++) { for (i = 0 ; i < MAX_ARG_PAGES ; i++) {
if (bprm->page[i]) { if (bprm->page[i]) {
info->rss++; info->rss++;
@ -703,7 +565,6 @@ static unsigned long create_elf_tables(target_ulong p, int argc, int envc,
unsigned long interp_load_addr, int ibcs, unsigned long interp_load_addr, int ibcs,
struct image_info *info) struct image_info *info)
{ {
target_ulong argv, envp;
target_ulong sp; target_ulong sp;
int size; int size;
target_ulong u_platform; target_ulong u_platform;
@ -765,28 +626,7 @@ static unsigned long create_elf_tables(target_ulong p, int argc, int envc,
#endif #endif
#undef NEW_AUX_ENT #undef NEW_AUX_ENT
sp -= (envc + 1) * n; sp = loader_build_argptr(envc, argc, sp, p, !ibcs);
envp = sp;
sp -= (argc + 1) * n;
argv = sp;
if (!ibcs) {
sp -= n; tputl(sp, envp);
sp -= n; tputl(sp, argv);
}
sp -= n; tputl(sp, argc);
info->arg_start = p;
while (argc-->0) {
tputl(argv, p); argv += n;
p += target_strlen(p) + 1;
}
tputl(argv, 0);
info->arg_end = info->env_start = p;
while (envc-->0) {
tputl(envp, p); envp += n;
p += target_strlen(p) + 1;
}
tputl(envp, 0);
info->env_end = p;
return sp; return sp;
} }
@ -1001,7 +841,7 @@ static void load_symbols(struct elfhdr *hdr, int fd)
syminfos = s; syminfos = s;
} }
static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * regs, int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * regs,
struct image_info * info) struct image_info * info)
{ {
struct elfhdr elf_ex; struct elfhdr elf_ex;
@ -1034,17 +874,19 @@ static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * r
bswap_ehdr(&elf_ex); bswap_ehdr(&elf_ex);
#endif #endif
if (elf_ex.e_ident[0] != 0x7f ||
strncmp(&elf_ex.e_ident[1], "ELF",3) != 0) {
return -ENOEXEC;
}
/* First of all, some simple consistency checks */ /* First of all, some simple consistency checks */
if ((elf_ex.e_type != ET_EXEC && elf_ex.e_type != ET_DYN) || if ((elf_ex.e_type != ET_EXEC && elf_ex.e_type != ET_DYN) ||
(! elf_check_arch(elf_ex.e_machine))) { (! elf_check_arch(elf_ex.e_machine))) {
return -ENOEXEC; return -ENOEXEC;
} }
bprm->p = copy_elf_strings(1, &bprm->filename, bprm->page, bprm->p);
bprm->p = copy_elf_strings(bprm->envc,bprm->envp,bprm->page,bprm->p);
bprm->p = copy_elf_strings(bprm->argc,bprm->argv,bprm->page,bprm->p);
if (!bprm->p) {
retval = -E2BIG;
}
/* Now read in all of the header information */ /* Now read in all of the header information */
elf_phdata = (struct elf_phdr *)malloc(elf_ex.e_phentsize*elf_ex.e_phnum); elf_phdata = (struct elf_phdr *)malloc(elf_ex.e_phentsize*elf_ex.e_phnum);
if (elf_phdata == NULL) { if (elf_phdata == NULL) {
@ -1188,7 +1030,7 @@ static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * r
/* OK, we are done with that, now set up the arg stuff, /* OK, we are done with that, now set up the arg stuff,
and then start this sucker up */ and then start this sucker up */
if (!bprm->sh_bang) { {
char * passed_p; char * passed_p;
if (interpreter_type == INTERPRETER_AOUT) { if (interpreter_type == INTERPRETER_AOUT) {
@ -1196,7 +1038,7 @@ static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * r
passed_p = passed_fileno; passed_p = passed_fileno;
if (elf_interpreter) { if (elf_interpreter) {
bprm->p = copy_strings(1,&passed_p,bprm->page,bprm->p); bprm->p = copy_elf_strings(1,&passed_p,bprm->page,bprm->p);
bprm->argc++; bprm->argc++;
} }
} }
@ -1347,11 +1189,10 @@ static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * r
interp_load_addr, interp_load_addr,
(interpreter_type == INTERPRETER_AOUT ? 0 : 1), (interpreter_type == INTERPRETER_AOUT ? 0 : 1),
info); info);
if (interpreter_type == INTERPRETER_AOUT)
info->arg_start += strlen(passed_fileno) + 1;
info->start_brk = info->brk = elf_brk; info->start_brk = info->brk = elf_brk;
info->end_code = end_code; info->end_code = end_code;
info->start_code = start_code; info->start_code = start_code;
info->start_data = end_code;
info->end_data = end_data; info->end_data = end_data;
info->start_stack = bprm->p; info->start_stack = bprm->p;
@ -1380,79 +1221,18 @@ static int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * r
MAP_FIXED | MAP_PRIVATE, -1, 0); MAP_FIXED | MAP_PRIVATE, -1, 0);
} }
#ifdef ELF_PLAT_INIT
/*
* The ABI may specify that certain registers be set up in special
* ways (on i386 %edx is the address of a DT_FINI function, for
* example. This macro performs whatever initialization to
* the regs structure is required.
*/
ELF_PLAT_INIT(regs);
#endif
info->entry = elf_entry; info->entry = elf_entry;
return 0; return 0;
} }
int elf_exec(const char * filename, char ** argv, char ** envp,
struct target_pt_regs * regs, struct image_info *infop)
{
struct linux_binprm bprm;
int retval;
int i;
bprm.p = TARGET_PAGE_SIZE*MAX_ARG_PAGES-sizeof(unsigned int);
for (i=0 ; i<MAX_ARG_PAGES ; i++) /* clear page-table */
bprm.page[i] = 0;
retval = open(filename, O_RDONLY);
if (retval < 0)
return retval;
bprm.fd = retval;
bprm.filename = (char *)filename;
bprm.sh_bang = 0;
bprm.loader = 0;
bprm.exec = 0;
bprm.dont_iput = 0;
bprm.argc = count(argv);
bprm.envc = count(envp);
retval = prepare_binprm(&bprm);
if(retval>=0) {
bprm.p = copy_strings(1, &bprm.filename, bprm.page, bprm.p);
bprm.exec = bprm.p;
bprm.p = copy_strings(bprm.envc,envp,bprm.page,bprm.p);
bprm.p = copy_strings(bprm.argc,argv,bprm.page,bprm.p);
if (!bprm.p) {
retval = -E2BIG;
}
}
if(retval>=0) {
retval = load_elf_binary(&bprm,regs,infop);
}
if(retval>=0) {
/* success. Initialize important registers */
init_thread(regs, infop);
return retval;
}
/* Something went wrong, return the inode and free the argument pages*/
for (i=0 ; i<MAX_ARG_PAGES ; i++) {
free(bprm.page[i]);
}
return(retval);
}
static int load_aout_interp(void * exptr, int interp_fd) static int load_aout_interp(void * exptr, int interp_fd)
{ {
printf("a.out interpreter not yet supported\n"); printf("a.out interpreter not yet supported\n");
return(0); return(0);
} }
void do_init_thread(struct target_pt_regs *regs, struct image_info *infop)
{
init_thread(regs, infop);
}

67
linux-user/flat.h Normal file
View File

@ -0,0 +1,67 @@
/*
* Copyright (C) 2002-2003 David McCullough <davidm@snapgear.com>
* Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
* The Silver Hammer Group, Ltd.
*
* This file provides the definitions and structures needed to
* support uClinux flat-format executables.
*/
#define FLAT_VERSION 0x00000004L
#ifdef CONFIG_BINFMT_SHARED_FLAT
#define MAX_SHARED_LIBS (4)
#else
#define MAX_SHARED_LIBS (1)
#endif
/*
* To make everything easier to port and manage cross platform
* development, all fields are in network byte order.
*/
struct flat_hdr {
char magic[4];
unsigned long rev; /* version (as above) */
unsigned long entry; /* Offset of first executable instruction
with text segment from beginning of file */
unsigned long data_start; /* Offset of data segment from beginning of
file */
unsigned long data_end; /* Offset of end of data segment
from beginning of file */
unsigned long bss_end; /* Offset of end of bss segment from beginning
of file */
/* (It is assumed that data_end through bss_end forms the bss segment.) */
unsigned long stack_size; /* Size of stack, in bytes */
unsigned long reloc_start; /* Offset of relocation records from
beginning of file */
unsigned long reloc_count; /* Number of relocation records */
unsigned long flags;
unsigned long build_date; /* When the program/library was built */
unsigned long filler[5]; /* Reservered, set to zero */
};
#define FLAT_FLAG_RAM 0x0001 /* load program entirely into RAM */
#define FLAT_FLAG_GOTPIC 0x0002 /* program is PIC with GOT */
#define FLAT_FLAG_GZIP 0x0004 /* all but the header is compressed */
#define FLAT_FLAG_GZDATA 0x0008 /* only data/relocs are compressed (for XIP) */
#define FLAT_FLAG_KTRACE 0x0010 /* output useful kernel trace for debugging */
/*
* While it would be nice to keep this header clean, users of older
* tools still need this support in the kernel. So this section is
* purely for compatibility with old tool chains.
*
* DO NOT make changes or enhancements to the old format please, just work
* with the format above, except to fix bugs with old format support.
*/
#define OLD_FLAT_VERSION 0x00000002L
#define OLD_FLAT_RELOC_TYPE_TEXT 0
#define OLD_FLAT_RELOC_TYPE_DATA 1
#define OLD_FLAT_RELOC_TYPE_BSS 2
# define OLD_FLAT_FLAG_RAM 0x1 /* load program entirely into RAM */

790
linux-user/flatload.c Normal file
View File

@ -0,0 +1,790 @@
/****************************************************************************/
/*
* QEMU bFLT binary loader. Based on linux/fs/binfmt_flat.c
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Copyright (C) 2006 CodeSourcery.
* Copyright (C) 2000-2003 David McCullough <davidm@snapgear.com>
* Copyright (C) 2002 Greg Ungerer <gerg@snapgear.com>
* Copyright (C) 2002 SnapGear, by Paul Dale <pauli@snapgear.com>
* Copyright (C) 2000, 2001 Lineo, by David McCullough <davidm@lineo.com>
* based heavily on:
*
* linux/fs/binfmt_aout.c:
* Copyright (C) 1991, 1992, 1996 Linus Torvalds
* linux/fs/binfmt_flat.c for 2.0 kernel
* Copyright (C) 1998 Kenneth Albanowski <kjahds@kjahds.com>
* JAN/99 -- coded full program relocation (gerg@snapgear.com)
*/
/* ??? ZFLAT and shared library support is currently disabled. */
/****************************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/mman.h>
#include <unistd.h>
#include "qemu.h"
#include "flat.h"
//#define DEBUG
#ifdef DEBUG
#define DBG_FLT(a...) printf(a)
#else
#define DBG_FLT(a...)
#endif
#define flat_reloc_valid(reloc, size) ((reloc) <= (size))
#define flat_old_ram_flag(flag) (flag)
#ifdef TARGET_WORDS_BIGENDIAN
#define flat_get_relocate_addr(relval) (relval)
#else
#define flat_get_relocate_addr(relval) bswap32(relval)
#endif
#define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
struct lib_info {
target_ulong start_code; /* Start of text segment */
target_ulong start_data; /* Start of data segment */
target_ulong end_data; /* Start of bss section */
target_ulong start_brk; /* End of data segment */
target_ulong text_len; /* Length of text segment */
target_ulong entry; /* Start address for this module */
target_ulong build_date; /* When this one was compiled */
short loaded; /* Has this library been loaded? */
};
#ifdef CONFIG_BINFMT_SHARED_FLAT
static int load_flat_shared_library(int id, struct lib_info *p);
#endif
struct linux_binprm;
#define ntohl(x) be32_to_cpu(x)
/****************************************************************************/
/*
* create_flat_tables() parses the env- and arg-strings in new user
* memory and creates the pointer tables from them, and puts their
* addresses on the "stack", returning the new stack pointer value.
*/
/* Push a block of strings onto the guest stack. */
static target_ulong copy_strings(target_ulong p, int n, char **s)
{
int len;
while (n-- > 0) {
len = strlen(s[n]) + 1;
p -= len;
memcpy_to_target(p, s[n], len);
}
return p;
}
int target_pread(int fd, target_ulong ptr, target_ulong len,
target_ulong offset)
{
void *buf;
int ret;
buf = lock_user(ptr, len, 0);
ret = pread(fd, buf, len, offset);
unlock_user(buf, ptr, len);
return ret;
}
/****************************************************************************/
#ifdef CONFIG_BINFMT_ZFLAT
#include <linux/zlib.h>
#define LBUFSIZE 4000
/* gzip flag byte */
#define ASCII_FLAG 0x01 /* bit 0 set: file probably ASCII text */
#define CONTINUATION 0x02 /* bit 1 set: continuation of multi-part gzip file */
#define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
#define ORIG_NAME 0x08 /* bit 3 set: original file name present */
#define COMMENT 0x10 /* bit 4 set: file comment present */
#define ENCRYPTED 0x20 /* bit 5 set: file is encrypted */
#define RESERVED 0xC0 /* bit 6,7: reserved */
static int decompress_exec(
struct linux_binprm *bprm,
unsigned long offset,
char *dst,
long len,
int fd)
{
unsigned char *buf;
z_stream strm;
loff_t fpos;
int ret, retval;
DBG_FLT("decompress_exec(offset=%x,buf=%x,len=%x)\n",(int)offset, (int)dst, (int)len);
memset(&strm, 0, sizeof(strm));
strm.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
if (strm.workspace == NULL) {
DBG_FLT("binfmt_flat: no memory for decompress workspace\n");
return -ENOMEM;
}
buf = kmalloc(LBUFSIZE, GFP_KERNEL);
if (buf == NULL) {
DBG_FLT("binfmt_flat: no memory for read buffer\n");
retval = -ENOMEM;
goto out_free;
}
/* Read in first chunk of data and parse gzip header. */
fpos = offset;
ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
strm.next_in = buf;
strm.avail_in = ret;
strm.total_in = 0;
retval = -ENOEXEC;
/* Check minimum size -- gzip header */
if (ret < 10) {
DBG_FLT("binfmt_flat: file too small?\n");
goto out_free_buf;
}
/* Check gzip magic number */
if ((buf[0] != 037) || ((buf[1] != 0213) && (buf[1] != 0236))) {
DBG_FLT("binfmt_flat: unknown compression magic?\n");
goto out_free_buf;
}
/* Check gzip method */
if (buf[2] != 8) {
DBG_FLT("binfmt_flat: unknown compression method?\n");
goto out_free_buf;
}
/* Check gzip flags */
if ((buf[3] & ENCRYPTED) || (buf[3] & CONTINUATION) ||
(buf[3] & RESERVED)) {
DBG_FLT("binfmt_flat: unknown flags?\n");
goto out_free_buf;
}
ret = 10;
if (buf[3] & EXTRA_FIELD) {
ret += 2 + buf[10] + (buf[11] << 8);
if (unlikely(LBUFSIZE == ret)) {
DBG_FLT("binfmt_flat: buffer overflow (EXTRA)?\n");
goto out_free_buf;
}
}
if (buf[3] & ORIG_NAME) {
for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
;
if (unlikely(LBUFSIZE == ret)) {
DBG_FLT("binfmt_flat: buffer overflow (ORIG_NAME)?\n");
goto out_free_buf;
}
}
if (buf[3] & COMMENT) {
for (; ret < LBUFSIZE && (buf[ret] != 0); ret++)
;
if (unlikely(LBUFSIZE == ret)) {
DBG_FLT("binfmt_flat: buffer overflow (COMMENT)?\n");
goto out_free_buf;
}
}
strm.next_in += ret;
strm.avail_in -= ret;
strm.next_out = dst;
strm.avail_out = len;
strm.total_out = 0;
if (zlib_inflateInit2(&strm, -MAX_WBITS) != Z_OK) {
DBG_FLT("binfmt_flat: zlib init failed?\n");
goto out_free_buf;
}
while ((ret = zlib_inflate(&strm, Z_NO_FLUSH)) == Z_OK) {
ret = bprm->file->f_op->read(bprm->file, buf, LBUFSIZE, &fpos);
if (ret <= 0)
break;
if (ret >= (unsigned long) -4096)
break;
len -= ret;
strm.next_in = buf;
strm.avail_in = ret;
strm.total_in = 0;
}
if (ret < 0) {
DBG_FLT("binfmt_flat: decompression failed (%d), %s\n",
ret, strm.msg);
goto out_zlib;
}
retval = 0;
out_zlib:
zlib_inflateEnd(&strm);
out_free_buf:
kfree(buf);
out_free:
kfree(strm.workspace);
out:
return retval;
}
#endif /* CONFIG_BINFMT_ZFLAT */
/****************************************************************************/
static target_ulong
calc_reloc(target_ulong r, struct lib_info *p, int curid, int internalp)
{
target_ulong addr;
int id;
target_ulong start_brk;
target_ulong start_data;
target_ulong text_len;
target_ulong start_code;
#ifdef CONFIG_BINFMT_SHARED_FLAT
#error needs checking
if (r == 0)
id = curid; /* Relocs of 0 are always self referring */
else {
id = (r >> 24) & 0xff; /* Find ID for this reloc */
r &= 0x00ffffff; /* Trim ID off here */
}
if (id >= MAX_SHARED_LIBS) {
fprintf(stderr, "BINFMT_FLAT: reference 0x%x to shared library %d\n",
(unsigned) r, id);
goto failed;
}
if (curid != id) {
if (internalp) {
fprintf(stderr, "BINFMT_FLAT: reloc address 0x%x not "
"in same module (%d != %d)\n",
(unsigned) r, curid, id);
goto failed;
} else if ( ! p[id].loaded &&
load_flat_shared_library(id, p) > (unsigned long) -4096) {
fprintf(stderr, "BINFMT_FLAT: failed to load library %d\n", id);
goto failed;
}
/* Check versioning information (i.e. time stamps) */
if (p[id].build_date && p[curid].build_date
&& p[curid].build_date < p[id].build_date) {
fprintf(stderr, "BINFMT_FLAT: library %d is younger than %d\n",
id, curid);
goto failed;
}
}
#else
id = 0;
#endif
start_brk = p[id].start_brk;
start_data = p[id].start_data;
start_code = p[id].start_code;
text_len = p[id].text_len;
if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
fprintf(stderr, "BINFMT_FLAT: reloc outside program 0x%x "
"(0 - 0x%x/0x%x)\n",
(int) r,(int)(start_brk-start_code),(int)text_len);
goto failed;
}
if (r < text_len) /* In text segment */
addr = r + start_code;
else /* In data segment */
addr = r - text_len + start_data;
/* Range checked already above so doing the range tests is redundant...*/
return(addr);
failed:
abort();
return RELOC_FAILED;
}
/****************************************************************************/
/* ??? This does not handle endianness correctly. */
void old_reloc(struct lib_info *libinfo, uint32_t rl)
{
#ifdef DEBUG
char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
#endif
uint32_t *ptr;
uint32_t offset;
int reloc_type;
offset = rl & 0x3fffffff;
reloc_type = rl >> 30;
/* ??? How to handle this? */
#if defined(CONFIG_COLDFIRE)
ptr = (uint32_t *) (libinfo->start_code + offset);
#else
ptr = (uint32_t *) (libinfo->start_data + offset);
#endif
#ifdef DEBUG
fprintf(stderr, "Relocation of variable at DATASEG+%x "
"(address %p, currently %x) into segment %s\n",
offset, ptr, (int)*ptr, segment[reloc_type]);
#endif
switch (reloc_type) {
case OLD_FLAT_RELOC_TYPE_TEXT:
*ptr += libinfo->start_code;
break;
case OLD_FLAT_RELOC_TYPE_DATA:
*ptr += libinfo->start_data;
break;
case OLD_FLAT_RELOC_TYPE_BSS:
*ptr += libinfo->end_data;
break;
default:
fprintf(stderr, "BINFMT_FLAT: Unknown relocation type=%x\n",
reloc_type);
break;
}
DBG_FLT("Relocation became %x\n", (int)*ptr);
}
/****************************************************************************/
static int load_flat_file(struct linux_binprm * bprm,
struct lib_info *libinfo, int id, target_ulong *extra_stack)
{
struct flat_hdr * hdr;
target_ulong textpos = 0, datapos = 0, result;
target_ulong realdatastart = 0;
target_ulong text_len, data_len, bss_len, stack_len, flags;
target_ulong memp = 0; /* for finding the brk area */
target_ulong extra;
target_ulong reloc = 0, rp;
int i, rev, relocs = 0;
target_ulong fpos;
target_ulong start_code, end_code;
hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
text_len = ntohl(hdr->data_start);
data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
bss_len = ntohl(hdr->bss_end) - ntohl(hdr->data_end);
stack_len = ntohl(hdr->stack_size);
if (extra_stack) {
stack_len += *extra_stack;
*extra_stack = stack_len;
}
relocs = ntohl(hdr->reloc_count);
flags = ntohl(hdr->flags);
rev = ntohl(hdr->rev);
DBG_FLT("BINFMT_FLAT: Loading file: %s\n", bprm->filename);
if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
fprintf(stderr, "BINFMT_FLAT: bad magic/rev (0x%x, need 0x%x)\n",
rev, (int) FLAT_VERSION);
return -ENOEXEC;
}
/* Don't allow old format executables to use shared libraries */
if (rev == OLD_FLAT_VERSION && id != 0) {
fprintf(stderr, "BINFMT_FLAT: shared libraries are not available\n");
return -ENOEXEC;
}
/*
* fix up the flags for the older format, there were all kinds
* of endian hacks, this only works for the simple cases
*/
if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
flags = FLAT_FLAG_RAM;
#ifndef CONFIG_BINFMT_ZFLAT
if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
fprintf(stderr, "Support for ZFLAT executables is not enabled\n");
return -ENOEXEC;
}
#endif
/*
* calculate the extra space we need to map in
*/
extra = relocs * sizeof(target_ulong);
if (extra < bss_len + stack_len)
extra = bss_len + stack_len;
/*
* there are a couple of cases here, the separate code/data
* case, and then the fully copied to RAM case which lumps
* it all together.
*/
if ((flags & (FLAT_FLAG_RAM|FLAT_FLAG_GZIP)) == 0) {
/*
* this should give us a ROM ptr, but if it doesn't we don't
* really care
*/
DBG_FLT("BINFMT_FLAT: ROM mapping of file (we hope)\n");
textpos = target_mmap(0, text_len, PROT_READ|PROT_EXEC,
MAP_PRIVATE, bprm->fd, 0);
if (textpos == -1) {
fprintf(stderr, "Unable to mmap process text\n");
return -1;
}
realdatastart = target_mmap(0, data_len + extra +
MAX_SHARED_LIBS * sizeof(target_ulong),
PROT_READ|PROT_WRITE|PROT_EXEC,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (realdatastart == -1) {
fprintf(stderr, "Unable to allocate RAM for process data\n");
return realdatastart;
}
datapos = realdatastart + MAX_SHARED_LIBS * sizeof(target_ulong);
DBG_FLT("BINFMT_FLAT: Allocated data+bss+stack (%d bytes): %x\n",
(int)(data_len + bss_len + stack_len), (int)datapos);
fpos = ntohl(hdr->data_start);
#ifdef CONFIG_BINFMT_ZFLAT
if (flags & FLAT_FLAG_GZDATA) {
result = decompress_exec(bprm, fpos, (char *) datapos,
data_len + (relocs * sizeof(target_ulong)))
} else
#endif
{
result = target_pread(bprm->fd, datapos,
data_len + (relocs * sizeof(target_ulong)),
fpos);
}
if (result < 0) {
fprintf(stderr, "Unable to read data+bss\n");
return result;
}
reloc = datapos + (ntohl(hdr->reloc_start) - text_len);
memp = realdatastart;
} else {
textpos = target_mmap(0, text_len + data_len + extra +
MAX_SHARED_LIBS * sizeof(target_ulong),
PROT_READ | PROT_EXEC | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (textpos == -1 ) {
fprintf(stderr, "Unable to allocate RAM for process text/data\n");
return -1;
}
realdatastart = textpos + ntohl(hdr->data_start);
datapos = realdatastart + MAX_SHARED_LIBS * sizeof(target_ulong);
reloc = (textpos + ntohl(hdr->reloc_start) +
MAX_SHARED_LIBS * sizeof(target_ulong));
memp = textpos;
#ifdef CONFIG_BINFMT_ZFLAT
#error code needs checking
/*
* load it all in and treat it like a RAM load from now on
*/
if (flags & FLAT_FLAG_GZIP) {
result = decompress_exec(bprm, sizeof (struct flat_hdr),
(((char *) textpos) + sizeof (struct flat_hdr)),
(text_len + data_len + (relocs * sizeof(unsigned long))
- sizeof (struct flat_hdr)),
0);
memmove((void *) datapos, (void *) realdatastart,
data_len + (relocs * sizeof(unsigned long)));
} else if (flags & FLAT_FLAG_GZDATA) {
fpos = 0;
result = bprm->file->f_op->read(bprm->file,
(char *) textpos, text_len, &fpos);
if (result < (unsigned long) -4096)
result = decompress_exec(bprm, text_len, (char *) datapos,
data_len + (relocs * sizeof(unsigned long)), 0);
}
else
#endif
{
result = target_pread(bprm->fd, textpos,
text_len, 0);
if (result >= 0) {
result = target_pread(bprm->fd, datapos,
data_len + (relocs * sizeof(target_ulong)),
ntohl(hdr->data_start));
}
}
if (result < 0) {
fprintf(stderr, "Unable to read code+data+bss\n");
return result;
}
}
DBG_FLT("Mapping is 0x%x, Entry point is 0x%x, data_start is 0x%x\n",
(int)textpos, 0x00ffffff&ntohl(hdr->entry),
ntohl(hdr->data_start));
/* The main program needs a little extra setup in the task structure */
start_code = textpos + sizeof (struct flat_hdr);
end_code = textpos + text_len;
DBG_FLT("%s %s: TEXT=%x-%x DATA=%x-%x BSS=%x-%x\n",
id ? "Lib" : "Load", bprm->filename,
(int) start_code, (int) end_code,
(int) datapos,
(int) (datapos + data_len),
(int) (datapos + data_len),
(int) (((datapos + data_len + bss_len) + 3) & ~3));
text_len -= sizeof(struct flat_hdr); /* the real code len */
/* Store the current module values into the global library structure */
libinfo[id].start_code = start_code;
libinfo[id].start_data = datapos;
libinfo[id].end_data = datapos + data_len;
libinfo[id].start_brk = datapos + data_len + bss_len;
libinfo[id].text_len = text_len;
libinfo[id].loaded = 1;
libinfo[id].entry = (0x00ffffff & ntohl(hdr->entry)) + textpos;
libinfo[id].build_date = ntohl(hdr->build_date);
/*
* We just load the allocations into some temporary memory to
* help simplify all this mumbo jumbo
*
* We've got two different sections of relocation entries.
* The first is the GOT which resides at the begining of the data segment
* and is terminated with a -1. This one can be relocated in place.
* The second is the extra relocation entries tacked after the image's
* data segment. These require a little more processing as the entry is
* really an offset into the image which contains an offset into the
* image.
*/
if (flags & FLAT_FLAG_GOTPIC) {
rp = datapos;
while (1) {
target_ulong addr;
addr = tgetl(rp);
if (addr == -1)
break;
if (addr) {
addr = calc_reloc(addr, libinfo, id, 0);
if (addr == RELOC_FAILED)
return -ENOEXEC;
tputl(rp, addr);
}
rp += sizeof(target_ulong);
}
}
/*
* Now run through the relocation entries.
* We've got to be careful here as C++ produces relocatable zero
* entries in the constructor and destructor tables which are then
* tested for being not zero (which will always occur unless we're
* based from address zero). This causes an endless loop as __start
* is at zero. The solution used is to not relocate zero addresses.
* This has the negative side effect of not allowing a global data
* reference to be statically initialised to _stext (I've moved
* __start to address 4 so that is okay).
*/
if (rev > OLD_FLAT_VERSION) {
for (i = 0; i < relocs; i++) {
target_ulong addr, relval;
/* Get the address of the pointer to be
relocated (of course, the address has to be
relocated first). */
relval = tgetl(reloc + i * sizeof (target_ulong));
addr = flat_get_relocate_addr(relval);
rp = calc_reloc(addr, libinfo, id, 1);
if (rp == RELOC_FAILED)
return -ENOEXEC;
/* Get the pointer's value. */
addr = tgetl(rp);
if (addr != 0) {
/*
* Do the relocation. PIC relocs in the data section are
* already in target order
*/
#ifndef TARGET_WORDS_BIGENDIAN
if ((flags & FLAT_FLAG_GOTPIC) == 0)
addr = bswap32(addr);
#endif
addr = calc_reloc(addr, libinfo, id, 0);
if (addr == RELOC_FAILED)
return -ENOEXEC;
/* Write back the relocated pointer. */
tputl(rp, addr);
}
}
} else {
for (i = 0; i < relocs; i++) {
target_ulong relval;
relval = tgetl(reloc + i * sizeof (target_ulong));
old_reloc(&libinfo[0], relval);
}
}
/* zero the BSS. */
memset((void*)(datapos + data_len), 0, bss_len);
return 0;
}
/****************************************************************************/
#ifdef CONFIG_BINFMT_SHARED_FLAT
/*
* Load a shared library into memory. The library gets its own data
* segment (including bss) but not argv/argc/environ.
*/
static int load_flat_shared_library(int id, struct lib_info *libs)
{
struct linux_binprm bprm;
int res;
char buf[16];
/* Create the file name */
sprintf(buf, "/lib/lib%d.so", id);
/* Open the file up */
bprm.filename = buf;
bprm.file = open_exec(bprm.filename);
res = PTR_ERR(bprm.file);
if (IS_ERR(bprm.file))
return res;
res = prepare_binprm(&bprm);
if (res <= (unsigned long)-4096)
res = load_flat_file(&bprm, libs, id, NULL);
if (bprm.file) {
allow_write_access(bprm.file);
fput(bprm.file);
bprm.file = NULL;
}
return(res);
}
#endif /* CONFIG_BINFMT_SHARED_FLAT */
int load_flt_binary(struct linux_binprm * bprm, struct target_pt_regs * regs,
struct image_info * info)
{
struct lib_info libinfo[MAX_SHARED_LIBS];
target_ulong p = bprm->p;
target_ulong stack_len;
target_ulong start_addr;
target_ulong sp;
int res;
int i, j;
memset(libinfo, 0, sizeof(libinfo));
/*
* We have to add the size of our arguments to our stack size
* otherwise it's too easy for users to create stack overflows
* by passing in a huge argument list. And yes, we have to be
* pedantic and include space for the argv/envp array as it may have
* a lot of entries.
*/
#define TOP_OF_ARGS (TARGET_PAGE_SIZE * MAX_ARG_PAGES - sizeof(void *))
stack_len = TOP_OF_ARGS - bprm->p; /* the strings */
stack_len += (bprm->argc + 1) * 4; /* the argv array */
stack_len += (bprm->envc + 1) * 4; /* the envp array */
res = load_flat_file(bprm, libinfo, 0, &stack_len);
if (res > (unsigned long)-4096)
return res;
/* Update data segment pointers for all libraries */
for (i=0; i<MAX_SHARED_LIBS; i++) {
if (libinfo[i].loaded) {
target_ulong p;
p = libinfo[i].start_data;
for (j=0; j<MAX_SHARED_LIBS; j++) {
p -= 4;
tput32(p, libinfo[j].loaded
? libinfo[j].start_data
: UNLOADED_LIB);
}
}
}
p = ((libinfo[0].start_brk + stack_len + 3) & ~3) - 4;
DBG_FLT("p=%x\n", (int)p);
/* Copy argv/envp. */
p = copy_strings(p, bprm->argc, bprm->argv);
p = copy_strings(p, bprm->envc, bprm->envp);
/* Align stack. */
sp = p & ~(target_ulong)(sizeof(target_ulong) - 1);
sp = loader_build_argptr(bprm->envc, bprm->argc, sp, p, 1);
/* Fake some return addresses to ensure the call chain will
* initialise library in order for us. We are required to call
* lib 1 first, then 2, ... and finally the main program (id 0).
*/
start_addr = libinfo[0].entry;
#ifdef CONFIG_BINFMT_SHARED_FLAT
#error here
for (i = MAX_SHARED_LIBS-1; i>0; i--) {
if (libinfo[i].loaded) {
/* Push previos first to call address */
--sp; put_user(start_addr, sp);
start_addr = libinfo[i].entry;
}
}
#endif
/* Stash our initial stack pointer into the mm structure */
info->start_code = libinfo[0].start_code;
info->end_code = libinfo[0].start_code = libinfo[0].text_len;
info->start_data = libinfo[0].start_data;
info->end_data = libinfo[0].end_data;
info->start_brk = libinfo[0].start_brk;
info->start_stack = sp;
info->entry = start_addr;
DBG_FLT("start_thread(entry=0x%x, start_stack=0x%x)\n",
(int)info->entry, (int)info->start_stack);
return 0;
}

195
linux-user/linuxload.c Normal file
View File

@ -0,0 +1,195 @@
/* Code for loading Linux executables. Mostly linux kenrel code. */
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include "qemu.h"
#define NGROUPS 32
/* ??? This should really be somewhere else. */
void memcpy_to_target(target_ulong dest, const void *src,
unsigned long len)
{
void *host_ptr;
host_ptr = lock_user(dest, len, 0);
memcpy(host_ptr, src, len);
unlock_user(host_ptr, dest, 1);
}
static int in_group_p(gid_t g)
{
/* return TRUE if we're in the specified group, FALSE otherwise */
int ngroup;
int i;
gid_t grouplist[NGROUPS];
ngroup = getgroups(NGROUPS, grouplist);
for(i = 0; i < ngroup; i++) {
if(grouplist[i] == g) {
return 1;
}
}
return 0;
}
static int count(char ** vec)
{
int i;
for(i = 0; *vec; i++) {
vec++;
}
return(i);
}
static int prepare_binprm(struct linux_binprm *bprm)
{
struct stat st;
int mode;
int retval, id_change;
if(fstat(bprm->fd, &st) < 0) {
return(-errno);
}
mode = st.st_mode;
if(!S_ISREG(mode)) { /* Must be regular file */
return(-EACCES);
}
if(!(mode & 0111)) { /* Must have at least one execute bit set */
return(-EACCES);
}
bprm->e_uid = geteuid();
bprm->e_gid = getegid();
id_change = 0;
/* Set-uid? */
if(mode & S_ISUID) {
bprm->e_uid = st.st_uid;
if(bprm->e_uid != geteuid()) {
id_change = 1;
}
}
/* Set-gid? */
/*
* If setgid is set but no group execute bit then this
* is a candidate for mandatory locking, not a setgid
* executable.
*/
if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
bprm->e_gid = st.st_gid;
if (!in_group_p(bprm->e_gid)) {
id_change = 1;
}
}
memset(bprm->buf, 0, sizeof(bprm->buf));
retval = lseek(bprm->fd, 0L, SEEK_SET);
if(retval >= 0) {
retval = read(bprm->fd, bprm->buf, 128);
}
if(retval < 0) {
perror("prepare_binprm");
exit(-1);
/* return(-errno); */
}
else {
return(retval);
}
}
/* Construct the envp and argv tables on the target stack. */
target_ulong loader_build_argptr(int envc, int argc, target_ulong sp,
target_ulong stringp, int push_ptr)
{
int n = sizeof(target_ulong);
target_ulong envp;
target_ulong argv;
sp -= (envc + 1) * n;
envp = sp;
sp -= (argc + 1) * n;
argv = sp;
if (push_ptr) {
sp -= n; tputl(sp, envp);
sp -= n; tputl(sp, argv);
}
sp -= n; tputl(sp, argc);
while (argc-- > 0) {
tputl(argv, stringp); argv += n;
stringp += target_strlen(stringp) + 1;
}
tputl(argv, 0);
while (envc-- > 0) {
tputl(envp, stringp); envp += n;
stringp += target_strlen(stringp) + 1;
}
tputl(envp, 0);
return sp;
}
int loader_exec(const char * filename, char ** argv, char ** envp,
struct target_pt_regs * regs, struct image_info *infop)
{
struct linux_binprm bprm;
int retval;
int i;
bprm.p = TARGET_PAGE_SIZE*MAX_ARG_PAGES-sizeof(unsigned int);
for (i=0 ; i<MAX_ARG_PAGES ; i++) /* clear page-table */
bprm.page[i] = 0;
retval = open(filename, O_RDONLY);
if (retval < 0)
return retval;
bprm.fd = retval;
bprm.filename = (char *)filename;
bprm.argc = count(argv);
bprm.argv = argv;
bprm.envc = count(envp);
bprm.envp = envp;
retval = prepare_binprm(&bprm);
if(retval>=0) {
if (bprm.buf[0] == 0x7f
&& bprm.buf[1] == 'E'
&& bprm.buf[2] == 'L'
&& bprm.buf[3] == 'F') {
retval = load_elf_binary(&bprm,regs,infop);
#if defined(TARGET_HAS_BFLT)
} else if (bprm.buf[0] == 'b'
&& bprm.buf[1] == 'F'
&& bprm.buf[2] == 'L'
&& bprm.buf[3] == 'T') {
retval = load_flt_binary(&bprm,regs,infop);
#endif
} else {
fprintf(stderr, "Unknown binary format\n");
return -1;
}
}
if(retval>=0) {
/* success. Initialize important registers */
do_init_thread(regs, infop);
return retval;
}
/* Something went wrong, return the inode and free the argument pages*/
for (i=0 ; i<MAX_ARG_PAGES ; i++) {
free(bprm.page[i]);
}
return(retval);
}

View File

@ -1545,7 +1545,7 @@ int main(int argc, char **argv)
env = cpu_init(); env = cpu_init();
global_env = env; global_env = env;
if (elf_exec(filename, argv+optind, environ, regs, info) != 0) { if (loader_exec(filename, argv+optind, environ, regs, info) != 0) {
printf("Error loading %s\n", filename); printf("Error loading %s\n", filename);
_exit(1); _exit(1);
} }
@ -1556,6 +1556,7 @@ int main(int argc, char **argv)
fprintf(logfile, "start_brk 0x%08lx\n" , info->start_brk); fprintf(logfile, "start_brk 0x%08lx\n" , info->start_brk);
fprintf(logfile, "end_code 0x%08lx\n" , info->end_code); fprintf(logfile, "end_code 0x%08lx\n" , info->end_code);
fprintf(logfile, "start_code 0x%08lx\n" , info->start_code); fprintf(logfile, "start_code 0x%08lx\n" , info->start_code);
fprintf(logfile, "start_data 0x%08lx\n" , info->start_data);
fprintf(logfile, "end_data 0x%08lx\n" , info->end_data); fprintf(logfile, "end_data 0x%08lx\n" , info->end_data);
fprintf(logfile, "start_stack 0x%08lx\n" , info->start_stack); fprintf(logfile, "start_stack 0x%08lx\n" , info->start_stack);
fprintf(logfile, "brk 0x%08lx\n" , info->brk); fprintf(logfile, "brk 0x%08lx\n" , info->brk);

View File

@ -18,6 +18,7 @@
struct image_info { struct image_info {
unsigned long start_code; unsigned long start_code;
unsigned long end_code; unsigned long end_code;
unsigned long start_data;
unsigned long end_data; unsigned long end_data;
unsigned long start_brk; unsigned long start_brk;
unsigned long brk; unsigned long brk;
@ -25,10 +26,6 @@ struct image_info {
unsigned long mmap; unsigned long mmap;
unsigned long rss; unsigned long rss;
unsigned long start_stack; unsigned long start_stack;
unsigned long arg_start;
unsigned long arg_end;
unsigned long env_start;
unsigned long env_end;
unsigned long entry; unsigned long entry;
int personality; int personality;
}; };
@ -82,9 +79,43 @@ typedef struct TaskState {
extern TaskState *first_task_state; extern TaskState *first_task_state;
extern const char *qemu_uname_release; extern const char *qemu_uname_release;
int elf_exec(const char * filename, char ** argv, char ** envp, /* ??? See if we can avoid exposing so much of the loader internals. */
/*
* MAX_ARG_PAGES defines the number of pages allocated for arguments
* and envelope for the new program. 32 should suffice, this gives
* a maximum env+arg of 128kB w/4KB pages!
*/
#define MAX_ARG_PAGES 32
/*
* This structure is used to hold the arguments that are
* used when loading binaries.
*/
struct linux_binprm {
char buf[128];
void *page[MAX_ARG_PAGES];
unsigned long p;
int fd;
int e_uid, e_gid;
int argc, envc;
char **argv;
char **envp;
char * filename; /* Name of binary */
};
void do_init_thread(struct target_pt_regs *regs, struct image_info *infop);
target_ulong loader_build_argptr(int envc, int argc, target_ulong sp,
target_ulong stringp, int push_ptr);
int loader_exec(const char * filename, char ** argv, char ** envp,
struct target_pt_regs * regs, struct image_info *infop); struct target_pt_regs * regs, struct image_info *infop);
int load_elf_binary(struct linux_binprm * bprm, struct target_pt_regs * regs,
struct image_info * info);
int load_flt_binary(struct linux_binprm * bprm, struct target_pt_regs * regs,
struct image_info * info);
void memcpy_to_target(target_ulong dest, const void *src,
unsigned long len);
void target_set_brk(target_ulong new_brk); void target_set_brk(target_ulong new_brk);
long do_brk(target_ulong new_brk); long do_brk(target_ulong new_brk);
void syscall_init(void); void syscall_init(void);