ref: fb7dd4b3a868cb8987049c95bb32e6425a73c8b9
dir: /utils/libmach/executable.c/
#include <lib9.h>
#include <bio.h>
#include "bootexec.h"
#include "mach.h"
#include "elf.h"
/*
* All a.out header types. The dummy entry allows canonical
* processing of the union as a sequence of longs
*/
typedef struct {
union{
Exec exec;
struct {
u32int ohdr[8]; /* Exec */
uvlong hdr[1];
} exechdr64;
Ehdr elfhdr32; /* elf.h */
struct mipsexec mips; /* bootexec.h */
struct mips4kexec mips4k; /* bootexec.h */
struct sparcexec sparc; /* bootexec.h */
struct nextexec next; /* bootexec.h */
} e;
u32int dummy; /* padding to ensure extra u32int */
} ExecHdr;
static int nextboot(int, Fhdr*, ExecHdr*);
static int sparcboot(int, Fhdr*, ExecHdr*);
static int mipsboot(int, Fhdr*, ExecHdr*);
static int mips4kboot(int, Fhdr*, ExecHdr*);
static int common(int, Fhdr*, ExecHdr*);
static int commonllp64(int, Fhdr*, ExecHdr*);
static int adotout(int, Fhdr*, ExecHdr*);
static int elfdotout(int, Fhdr*, ExecHdr*);
static int armdotout(int, Fhdr*, ExecHdr*);
static void setsym(Fhdr*, long, long, long, vlong);
static void setdata(Fhdr*, uvlong, long, vlong, long);
static void settext(Fhdr*, uvlong, uvlong, long, vlong);
static void hswal(void*, int, ulong(*)(ulong));
static uvlong _round(uvlong, ulong);
/*
* definition of per-executable file type structures
*/
typedef struct Exectable{
long magic; /* big-endian magic number of file */
char *name; /* executable identifier */
char *dlmname; /* dynamically loadable module identifier */
uchar type; /* Internal code */
uchar _magic; /* _MAGIC() magic */
Mach *mach; /* Per-machine data */
long hsize; /* header size */
ulong (*swal)(ulong); /* beswal or leswal */
int (*hparse)(int, Fhdr*, ExecHdr*);
} ExecTable;
extern Mach mmips;
extern Mach mmips2le;
extern Mach mmips2be;
extern Mach msparc;
extern Mach mi386;
extern Mach mamd64;
extern Mach marm;
extern Mach mpower;
extern Mach mpower64;
ExecTable exectab[] =
{
{ V_MAGIC, /* Mips v.out */
"mips plan 9 executable BE",
"mips plan 9 dlm BE",
FMIPS,
1,
&mmips,
sizeof(Exec),
beswal,
adotout },
{ P_MAGIC, /* Mips 0.out (r3k le) */
"mips plan 9 executable LE",
"mips plan 9 dlm LE",
FMIPSLE,
1,
&mmips,
sizeof(Exec),
beswal,
adotout },
{ M_MAGIC, /* Mips 4.out */
"mips 4k plan 9 executable BE",
"mips 4k plan 9 dlm BE",
FMIPS2BE,
1,
&mmips2be,
sizeof(Exec),
beswal,
adotout },
{ N_MAGIC, /* Mips 0.out */
"mips 4k plan 9 executable LE",
"mips 4k plan 9 dlm LE",
FMIPS2LE,
1,
&mmips2le,
sizeof(Exec),
beswal,
adotout },
{ 0x160<<16, /* Mips boot image */
"mips plan 9 boot image",
nil,
FMIPSB,
0,
&mmips,
sizeof(struct mipsexec),
beswal,
mipsboot },
{ (0x160<<16)|3, /* Mips boot image */
"mips 4k plan 9 boot image",
nil,
FMIPSB,
0,
&mmips2be,
sizeof(struct mips4kexec),
beswal,
mips4kboot },
{ K_MAGIC, /* Sparc k.out */
"sparc plan 9 executable",
"sparc plan 9 dlm",
FSPARC,
1,
&msparc,
sizeof(Exec),
beswal,
adotout },
{ 0x01030107, /* Sparc boot image */
"sparc plan 9 boot image",
nil,
FSPARCB,
0,
&msparc,
sizeof(struct sparcexec),
beswal,
sparcboot },
{ I_MAGIC, /* I386 8.out & boot image */
"386 plan 9 executable",
"386 plan 9 dlm",
FI386,
1,
&mi386,
sizeof(Exec),
beswal,
common },
{ S_MAGIC, /* amd64 6.out & boot image */
"amd64 plan 9 executable",
"amd64 plan 9 dlm",
FAMD64,
1,
&mamd64,
sizeof(Exec)+8,
nil,
commonllp64 },
{ Q_MAGIC, /* PowerPC q.out & boot image */
"power plan 9 executable",
"power plan 9 dlm",
FPOWER,
1,
&mpower,
sizeof(Exec),
beswal,
common },
{ T_MAGIC, /* power64 9.out & boot image */
"power64 plan 9 executable",
"power64 plan 9 dlm",
FPOWER64,
1,
&mpower64,
sizeof(Exec)+8,
nil,
commonllp64 },
{ ELF_MAG, /* any elf32 */
"elf executable",
nil,
FNONE,
0,
&mi386,
sizeof(Ehdr),
nil,
elfdotout },
{ E_MAGIC, /* Arm 5.out and boot image */
"arm plan 9 executable",
"arm plan 9 dlm",
FARM,
1,
&marm,
sizeof(Exec),
beswal,
common },
{ (143<<16)|0413, /* (Free|Net)BSD Arm */
"arm *bsd executable",
nil,
FARM,
0,
&marm,
sizeof(Exec),
leswal,
armdotout },
{ 0 },
};
Mach *mach = &mi386; /* Global current machine table */
static ExecTable*
couldbe4k(ExecTable *mp)
{
Dir *d;
ExecTable *f;
if((d=dirstat("/proc/1/regs")) == nil)
return mp;
if(d->length < 32*8){ /* R3000 */
free(d);
return mp;
}
free(d);
for (f = exectab; f->magic; f++)
if(f->magic == M_MAGIC) {
f->name = "mips plan 9 executable on mips2 kernel";
return f;
}
return mp;
}
int
crackhdr(int fd, Fhdr *fp)
{
ExecTable *mp;
ExecHdr d;
int nb, ret;
ulong magic;
fp->type = FNONE;
nb = read(fd, (char *)&d.e, sizeof(d.e));
if (nb <= 0)
return 0;
ret = 0;
magic = beswal(d.e.exec.magic); /* big-endian */
for (mp = exectab; mp->magic; mp++) {
if (nb < mp->hsize)
continue;
/*
* The.exec.magic number has morphed into something
* with fields (the straw was DYN_MAGIC) so now
* a flag is needed in Fhdr to distinguish _MAGIC()
* magic numbers from foreign magic numbers.
*
* This code is creaking a bit and if it has to
* be modified/extended much more it's probably
* time to step back and redo it all.
*/
if(mp->_magic){
if(mp->magic != (magic & ~DYN_MAGIC))
continue;
if(mp->magic == V_MAGIC)
mp = couldbe4k(mp);
if ((magic & DYN_MAGIC) && mp->dlmname != nil)
fp->name = mp->dlmname;
else
fp->name = mp->name;
}
else{
if(mp->magic != magic)
continue;
fp->name = mp->name;
}
fp->type = mp->type;
fp->hdrsz = mp->hsize; /* will be zero on bootables */
fp->_magic = mp->_magic;
fp->magic = magic;
mach = mp->mach;
if(mp->swal != nil)
hswal(&d, sizeof(d.e)/sizeof(ulong), mp->swal);
ret = mp->hparse(fd, fp, &d);
seek(fd, mp->hsize, 0); /* seek to end of header */
break;
}
if(mp->magic == 0)
werrstr("unknown header type");
return ret;
}
/*
* Convert header to canonical form
*/
static void
hswal(void *v, int n, ulong (*swap)(ulong))
{
ulong *ulp;
for(ulp = v; n--; ulp++)
*ulp = (*swap)(*ulp);
}
/*
* Crack a normal a.out-type header
*/
static int
adotout(int fd, Fhdr *fp, ExecHdr *hp)
{
long pgsize;
USED(fd);
pgsize = mach->pgsize;
settext(fp, hp->e.exec.entry, pgsize+sizeof(Exec),
hp->e.exec.text, sizeof(Exec));
setdata(fp, _round(pgsize+fp->txtsz+sizeof(Exec), pgsize),
hp->e.exec.data, fp->txtsz+sizeof(Exec), hp->e.exec.bss);
setsym(fp, hp->e.exec.syms, hp->e.exec.spsz, hp->e.exec.pcsz, fp->datoff+fp->datsz);
return 1;
}
static void
commonboot(Fhdr *fp)
{
if (!(fp->entry & mach->ktmask))
return;
switch(fp->type) { /* boot image */
case F68020:
fp->type = F68020B;
fp->name = "68020 plan 9 boot image";
break;
case FI386:
fp->type = FI386B;
fp->txtaddr = (u32int)fp->entry;
fp->name = "386 plan 9 boot image";
fp->dataddr = _round(fp->txtaddr+fp->txtsz, mach->pgsize);
break;
case FARM:
fp->type = FARMB;
fp->txtaddr = (u32int)fp->entry;
fp->name = "ARM plan 9 boot image";
fp->dataddr = _round(fp->txtaddr+fp->txtsz, mach->pgsize);
return;
case FPOWER:
fp->type = FPOWERB;
fp->txtaddr = (u32int)fp->entry;
fp->name = "power plan 9 boot image";
fp->dataddr = fp->txtaddr+fp->txtsz;
break;
case FAMD64:
fp->type = FAMD64B;
fp->txtaddr = fp->entry;
fp->name = "amd64 plan 9 boot image";
fp->dataddr = _round(fp->txtaddr+fp->txtsz, mach->pgsize);
break;
default:
return;
}
fp->hdrsz = 0; /* header stripped */
}
/*
* _MAGIC() style headers and
* alpha plan9-style bootable images for axp "headerless" boot
*
*/
static int
common(int fd, Fhdr *fp, ExecHdr *hp)
{
adotout(fd, fp, hp);
if(hp->e.exec.magic & DYN_MAGIC) {
fp->txtaddr = 0;
fp->dataddr = fp->txtsz;
return 1;
}
commonboot(fp);
return 1;
}
static int
commonllp64(int fd, Fhdr *fp, ExecHdr *hp)
{
long pgsize;
uvlong entry;
USED(fd);
hswal(&hp->e, sizeof(Exec)/sizeof(long), beswal);
if(!(hp->e.exec.magic & HDR_MAGIC))
return 0;
/*
* There can be more.exec.magic here if the
* header ever needs more expansion.
* For now just catch use of any of the
* unused bits.
*/
if((hp->e.exec.magic & ~DYN_MAGIC)>>16)
return 0;
entry = beswav(hp->e.exechdr64.hdr[0]);
pgsize = mach->pgsize;
settext(fp, entry, pgsize+fp->hdrsz, hp->e.exec.text, fp->hdrsz);
setdata(fp, _round(pgsize+fp->txtsz+fp->hdrsz, pgsize),
hp->e.exec.data, fp->txtsz+fp->hdrsz, hp->e.exec.bss);
setsym(fp, hp->e.exec.syms, hp->e.exec.spsz, hp->e.exec.pcsz, fp->datoff+fp->datsz);
if(hp->e.exec.magic & DYN_MAGIC) {
fp->txtaddr = 0;
fp->dataddr = fp->txtsz;
return 1;
}
commonboot(fp);
return 1;
}
/*
* mips bootable image.
*/
static int
mipsboot(int fd, Fhdr *fp, ExecHdr *hp)
{
USED(fd);
fp->type = FMIPSB;
switch(hp->e.mips.amagic) {
default:
case 0407: /* some kind of mips */
settext(fp, (u32int)hp->e.mips.mentry, (u32int)hp->e.mips.text_start,
hp->e.mips.tsize, sizeof(struct mipsexec)+4);
setdata(fp, (u32int)hp->e.mips.data_start, hp->e.mips.dsize,
fp->txtoff+hp->e.mips.tsize, hp->e.mips.bsize);
break;
case 0413: /* some kind of mips */
settext(fp, (u32int)hp->e.mips.mentry, (u32int)hp->e.mips.text_start,
hp->e.mips.tsize, 0);
setdata(fp, (u32int)hp->e.mips.data_start, hp->e.mips.dsize,
hp->e.mips.tsize, hp->e.mips.bsize);
break;
}
setsym(fp, hp->e.mips.nsyms, 0, hp->e.mips.pcsize, hp->e.mips.symptr);
fp->hdrsz = 0; /* header stripped */
return 1;
}
/*
* mips4k bootable image.
*/
static int
mips4kboot(int fd, Fhdr *fp, ExecHdr *hp)
{
USED(fd);
fp->type = FMIPSB;
switch(hp->e.mips4k.h.amagic) {
default:
case 0407: /* some kind of mips */
settext(fp, (u32int)hp->e.mips4k.h.mentry, (u32int)hp->e.mips4k.h.text_start,
hp->e.mips4k.h.tsize, sizeof(struct mips4kexec));
setdata(fp, (u32int)hp->e.mips4k.h.data_start, hp->e.mips4k.h.dsize,
fp->txtoff+hp->e.mips4k.h.tsize, hp->e.mips4k.h.bsize);
break;
case 0413: /* some kind of mips */
settext(fp, (u32int)hp->e.mips4k.h.mentry, (u32int)hp->e.mips4k.h.text_start,
hp->e.mips4k.h.tsize, 0);
setdata(fp, (u32int)hp->e.mips4k.h.data_start, hp->e.mips4k.h.dsize,
hp->e.mips4k.h.tsize, hp->e.mips4k.h.bsize);
break;
}
setsym(fp, hp->e.mips4k.h.nsyms, 0, hp->e.mips4k.h.pcsize, hp->e.mips4k.h.symptr);
fp->hdrsz = 0; /* header stripped */
return 1;
}
/*
* sparc bootable image
*/
static int
sparcboot(int fd, Fhdr *fp, ExecHdr *hp)
{
USED(fd);
fp->type = FSPARCB;
settext(fp, hp->e.sparc.sentry, hp->e.sparc.sentry, hp->e.sparc.stext,
sizeof(struct sparcexec));
setdata(fp, hp->e.sparc.sentry+hp->e.sparc.stext, hp->e.sparc.sdata,
fp->txtoff+hp->e.sparc.stext, hp->e.sparc.sbss);
setsym(fp, hp->e.sparc.ssyms, 0, hp->e.sparc.sdrsize, fp->datoff+hp->e.sparc.sdata);
fp->hdrsz = 0; /* header stripped */
return 1;
}
/*
* next bootable image
*/
static int
nextboot(int fd, Fhdr *fp, ExecHdr *hp)
{
USED(fd);
fp->type = FNEXTB;
settext(fp, hp->e.next.textc.vmaddr, hp->e.next.textc.vmaddr,
hp->e.next.texts.size, hp->e.next.texts.offset);
setdata(fp, hp->e.next.datac.vmaddr, hp->e.next.datas.size,
hp->e.next.datas.offset, hp->e.next.bsss.size);
setsym(fp, hp->e.next.symc.nsyms, hp->e.next.symc.spoff, hp->e.next.symc.pcoff,
hp->e.next.symc.symoff);
fp->hdrsz = 0; /* header stripped */
return 1;
}
/*
* Elf32 binaries.
*/
static int
elfdotout(int fd, Fhdr *fp, ExecHdr *hp)
{
ulong (*swal)(ulong);
ushort (*swab)(ushort);
Ehdr *ep;
Phdr *ph;
int i, it, id, is, phsz;
/* bitswap the header according to the DATA format */
ep = &hp->e.elfhdr32;
if(ep->ident[CLASS] != ELFCLASS32) {
werrstr("bad ELF class - not 32 bit");
return 0;
}
if(ep->ident[DATA] == ELFDATA2LSB) {
swab = leswab;
swal = leswal;
} else if(ep->ident[DATA] == ELFDATA2MSB) {
swab = beswab;
swal = beswal;
} else {
werrstr("bad ELF encoding - not big or little endian");
return 0;
}
ep->type = swab(ep->type);
ep->machine = swab(ep->machine);
ep->version = swal(ep->version);
ep->elfentry = swal(ep->elfentry);
ep->phoff = swal(ep->phoff);
ep->shoff = swal(ep->shoff);
ep->flags = swal(ep->flags);
ep->ehsize = swab(ep->ehsize);
ep->phentsize = swab(ep->phentsize);
ep->phnum = swab(ep->phnum);
ep->shentsize = swab(ep->shentsize);
ep->shnum = swab(ep->shnum);
ep->shstrndx = swab(ep->shstrndx);
if(ep->type != EXEC || ep->version != CURRENT)
return 0;
/* we could definitely support a lot more machines here */
fp->magic = ELF_MAG;
fp->hdrsz = (ep->ehsize+ep->phnum*ep->phentsize+16)&~15;
switch(ep->machine) {
case I386:
mach = &mi386;
fp->type = FI386;
break;
case MIPS:
mach = &mmips;
fp->type = FMIPS;
break;
case SPARC64:
return 0;
case POWER:
mach = &mpower;
fp->type = FPOWER;
break;
case AMD64:
mach = &mamd64;
fp->type = FAMD64;
break;
case ARM:
mach = &marm;
fp->type = FARM;
break;
default:
return 0;
}
if(ep->phentsize != sizeof(Phdr)) {
werrstr("bad ELF header size");
return 0;
}
phsz = sizeof(Phdr)*ep->phnum;
ph = malloc(phsz);
if(!ph)
return 0;
seek(fd, ep->phoff, 0);
if(read(fd, ph, phsz) < 0) {
free(ph);
return 0;
}
hswal(ph, phsz/sizeof(ulong), swal);
/* find text, data and symbols and install them */
it = id = is = -1;
for(i = 0; i < ep->phnum; i++) {
if(ph[i].type == LOAD
&& (ph[i].flags & (R|X)) == (R|X) && it == -1)
it = i;
else if(ph[i].type == LOAD
&& (ph[i].flags & (R|W)) == (R|W) && id == -1)
id = i;
else if(ph[i].type == NOPTYPE && is == -1)
is = i;
}
if(it == -1 || id == -1) {
/*
* The SPARC64 boot image is something of an ELF hack.
* Text+Data+BSS are represented by ph[0]. Symbols
* are represented by ph[1]:
*
* filesz, memsz, vaddr, paddr, off
* ph[0] : txtsz+datsz, txtsz+datsz+bsssz, txtaddr-KZERO, datasize, txtoff
* ph[1] : symsz, lcsz, 0, 0, symoff
*/
if(ep->machine == SPARC64 && ep->phnum == 2) {
ulong txtaddr, txtsz, dataddr, bsssz;
txtaddr = ph[0].vaddr | 0x80000000;
txtsz = ph[0].filesz - ph[0].paddr;
dataddr = txtaddr + txtsz;
bsssz = ph[0].memsz - ph[0].filesz;
settext(fp, ep->elfentry | 0x80000000, txtaddr, txtsz, ph[0].offset);
setdata(fp, dataddr, ph[0].paddr, ph[0].offset + txtsz, bsssz);
setsym(fp, ph[1].filesz, 0, ph[1].memsz, ph[1].offset);
free(ph);
return 1;
}
werrstr("No TEXT or DATA sections");
free(ph);
return 0;
}
settext(fp, ep->elfentry, ph[it].vaddr, ph[it].memsz, ph[it].offset);
setdata(fp, ph[id].vaddr, ph[id].filesz, ph[id].offset, ph[id].memsz - ph[id].filesz);
if(is != -1)
setsym(fp, ph[is].filesz, 0, ph[is].memsz, ph[is].offset);
free(ph);
return 1;
}
/*
* (Free|Net)BSD ARM header.
*/
static int
armdotout(int fd, Fhdr *fp, ExecHdr *hp)
{
uvlong kbase;
USED(fd);
settext(fp, hp->e.exec.entry, sizeof(Exec), hp->e.exec.text, sizeof(Exec));
setdata(fp, fp->txtsz, hp->e.exec.data, fp->txtsz, hp->e.exec.bss);
setsym(fp, hp->e.exec.syms, hp->e.exec.spsz, hp->e.exec.pcsz, fp->datoff+fp->datsz);
kbase = 0xF0000000;
if ((fp->entry & kbase) == kbase) { /* Boot image */
fp->txtaddr = kbase+sizeof(Exec);
fp->name = "ARM *BSD boot image";
fp->hdrsz = 0; /* header stripped */
fp->dataddr = kbase+fp->txtsz;
}
return 1;
}
static void
settext(Fhdr *fp, uvlong e, uvlong a, long s, vlong off)
{
fp->txtaddr = a;
fp->entry = e;
fp->txtsz = s;
fp->txtoff = off;
}
static void
setdata(Fhdr *fp, uvlong a, long s, vlong off, long bss)
{
fp->dataddr = a;
fp->datsz = s;
fp->datoff = off;
fp->bsssz = bss;
}
static void
setsym(Fhdr *fp, long symsz, long sppcsz, long lnpcsz, vlong symoff)
{
fp->symsz = symsz;
fp->symoff = symoff;
fp->sppcsz = sppcsz;
fp->sppcoff = fp->symoff+fp->symsz;
fp->lnpcsz = lnpcsz;
fp->lnpcoff = fp->sppcoff+fp->sppcsz;
}
static uvlong
_round(uvlong a, ulong b)
{
uvlong w;
w = (a/b)*b;
if (a!=w)
w += b;
return(w);
}