static int
readehdr(Boot *b)
{
int i;
/* bitswap the header according to the DATA format */
if(ehdr.ident[CLASS] != ELFCLASS32) {
print("bad ELF class - not 32 bit\n");
return 0;
}
if(ehdr.ident[DATA] == ELFDATA2LSB) {
swab = leswab;
swal = leswal;
} else if(ehdr.ident[DATA] == ELFDATA2MSB) {
swab = beswab;
swal = beswal;
} else {
print("bad ELF encoding - not big or little endian\n");
return 0;
}
memmove(&rehdr, &ehdr, sizeof(Ehdr));
ehdr.type = swab(ehdr.type);
ehdr.machine = swab(ehdr.machine);
ehdr.version = swal(ehdr.version);
ehdr.elfentry = swal(ehdr.elfentry);
ehdr.phoff = swal(ehdr.phoff);
ehdr.shoff = swal(ehdr.shoff);
ehdr.flags = swal(ehdr.flags);
ehdr.ehsize = swab(ehdr.ehsize);
ehdr.phentsize = swab(ehdr.phentsize);
ehdr.phnum = swab(ehdr.phnum);
ehdr.shentsize = swab(ehdr.shentsize);
ehdr.shnum = swab(ehdr.shnum);
ehdr.shstrndx = swab(ehdr.shstrndx);
if(ehdr.type != EXEC || ehdr.version != CURRENT)
return 0;
if(ehdr.phentsize != sizeof(Phdr))
return 0;
if(debug)
print("readehdr OK entry 0x%lux\n", ehdr.elfentry);
curoff = sizeof(Ehdr);
i = ehdr.phoff+ehdr.phentsize*ehdr.phnum - curoff;
b->state = READPHDR;
b->bp = (char*)malloc(i);
b->wp = b->bp;
b->ep = b->wp + i;
phdr = (Phdr*)(b->bp + ehdr.phoff-sizeof(Ehdr));
if(debug)
print("phdr...");
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;
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:
mach = &msparc64;
fp->type = FSPARC64;
break;
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;
}
/*
* ELF64 binaries.
*/
static int
elf64dotout(int fd, Fhdr *fp, ExecHdr *hp)
{
E64hdr *ep;
P64hdr *ph;
ushort (*swab)(ushort);
ulong (*swal)(ulong);
uvlong (*swav)(uvlong);
int i, it, id, is, phsz;
uvlong uvl;
ep = &hp->e;
if(ep->ident[DATA] == ELFDATA2LSB) {
swab = leswab;
swal = leswal;
swav = leswav;
} else if(ep->ident[DATA] == ELFDATA2MSB) {
swab = beswab;
swal = beswal;
swav = beswav;
} else {
werrstr("bad ELF64 encoding - not big or little endian");
return 0;
}
ep->type = swab(ep->type);
ep->machine = swab(ep->machine);
ep->version = swal(ep->version);
if(ep->type != EXEC || ep->version != CURRENT)
return 0;
ep->elfentry = swav(ep->elfentry);
ep->phoff = swav(ep->phoff);
ep->shoff = swav(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);
fp->magic = ELF_MAG;
fp->hdrsz = (ep->ehsize+ep->phnum*ep->phentsize+16)&~15;
switch(ep->machine) {
default:
return 0;
case AMD64:
mach = &mamd64;
fp->type = FAMD64;
fp->name = "amd64 ELF64 executable";
break;
case POWER64:
mach = &mpower64;
fp->type = FPOWER64;
fp->name = "power64 ELF64 executable";
break;
}
if(ep->phentsize != sizeof(P64hdr)) {
werrstr("bad ELF64 header size");
return 0;
}
phsz = sizeof(P64hdr)*ep->phnum;
ph = malloc(phsz);
if(!ph)
return 0;
seek(fd, ep->phoff, 0);
if(read(fd, ph, phsz) < 0) {
free(ph);
return 0;
}
for(i = 0; i < ep->phnum; i++) {
ph[i].type = swal(ph[i].type);
ph[i].flags = swal(ph[i].flags);
ph[i].offset = swav(ph[i].offset);
ph[i].vaddr = swav(ph[i].vaddr);
ph[i].paddr = swav(ph[i].paddr);
ph[i].filesz = swav(ph[i].filesz);
ph[i].memsz = swav(ph[i].memsz);
ph[i].align = swav(ph[i].align);
}
/* 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) {
werrstr("No ELF64 TEXT or DATA sections");
free(ph);
return 0;
}
settext(fp, ep->elfentry, ph[it].vaddr, ph[it].memsz, ph[it].offset);
/* 8c: out of fixed registers */
uvl = ph[id].memsz - ph[id].filesz;
setdata(fp, ph[id].vaddr, ph[id].filesz, ph[id].offset, uvl);
if(is != -1)
setsym(fp, ph[is].filesz, 0, ph[is].memsz, ph[is].offset);
free(ph);
return 1;
}
static int
machdotout(int fd, Fhdr *fp, ExecHdr *hp)
{
uvlong (*swav)(uvlong);
uint32 (*swal)(uint32);
Machhdr *mp;
MachCmd **cmd;
MachSymSeg *symtab;
MachSymSeg *pclntab;
MachSeg64 *seg;
MachSect64 *sect;
MachSeg32 *seg32;
MachSect32 *sect32;
uvlong textsize, datasize, bsssize;
uchar *cmdbuf;
uchar *cmdp;
int i, j, hdrsize;
uint32 textva, textoff, datava, dataoff, symoff, symsize, pclnoff, pclnsize;
mp = &hp->e.machhdr;
if (leswal(mp->filetype) != MACH_EXECUTABLE_TYPE) {
werrstr("bad MACH executable type %#ux", leswal(mp->filetype));
return 0;
}
swal = leswal;
swav = leswav;
mp->magic = swal(mp->magic);
mp->cputype = swal(mp->cputype);
mp->cpusubtype = swal(mp->cpusubtype);
mp->filetype = swal(mp->filetype);
mp->ncmds = swal(mp->ncmds);
mp->sizeofcmds = swal(mp->sizeofcmds);
mp->flags = swal(mp->flags);
mp->reserved = swal(mp->reserved);
switch(mp->magic) {
case 0xFEEDFACE: // 32-bit mach
if (mp->cputype != MACH_CPU_TYPE_X86) {
werrstr("bad MACH cpu type - not 386");
return 0;
}
if (mp->cpusubtype != MACH_CPU_SUBTYPE_X86) {
werrstr("bad MACH cpu subtype - not 386");
return 0;
}
if (mp->filetype != MACH_EXECUTABLE_TYPE) {
werrstr("bad MACH executable type");
return 0;
}
mach = &mi386;
fp->type = FI386;
hdrsize = 28;
break;
case 0xFEEDFACF: // 64-bit mach
werrstr("64 bit mach NOT SUPPORTED");
return 0;
//if (mp->cputype != MACH_CPU_TYPE_X86_64) {
// werrstr("bad MACH cpu type - not amd64");
// return 0;
//}
//
//if (mp->cpusubtype != MACH_CPU_SUBTYPE_X86 && mp->cpusubtype != MACH_CPU_SUBTYPE_X86_64) {
// werrstr("bad MACH cpu subtype - not amd64");
// return 0;
//}
//mach = &mamd64;
//fp->type = FAMD64;
//hdrsize = 32;
//break;
default:
werrstr("not mach %#ux", mp->magic);
return 0;
}
cmdbuf = malloc(mp->sizeofcmds);
if(!cmdbuf) {
werrstr("out of memory");
return 0;
}
seek(fd, hdrsize, 0);
if(read(fd, cmdbuf, mp->sizeofcmds) != mp->sizeofcmds) {
free(cmdbuf);
return 0;
}
cmd = malloc(mp->ncmds * sizeof(MachCmd*));
if(!cmd) {
free(cmdbuf);
werrstr("out of memory");
return 0;
}
cmdp = cmdbuf;
textva = 0;
textoff = 0;
dataoff = 0;
datava = 0;
symtab = 0;
pclntab = 0;
textsize = 0;
datasize = 0;
bsssize = 0;
symoff = 0;
symsize = 0;
pclnoff = 0;
pclnsize = 0;
for (i = 0; i < mp->ncmds; i++) {
MachCmd *c;
cmd[i] = (MachCmd*)cmdp;
c = cmd[i];
c->type = swal(c->type);
c->size = swal(c->size);
switch(c->type) {
case MACH_SEGMENT_32:
if(mp->magic != 0xFEEDFACE) {
werrstr("segment 32 in mach 64");
goto bad;
}
seg32 = (MachSeg32*)c;
seg32->vmaddr = swav(seg32->vmaddr);
seg32->vmsize = swav(seg32->vmsize);
seg32->fileoff = swav(seg32->fileoff);
seg32->filesize = swav(seg32->filesize);
seg32->maxprot = swal(seg32->maxprot);
seg32->initprot = swal(seg32->initprot);
seg32->nsects = swal(seg32->nsects);
seg32->flags = swal(seg32->flags);
if (strcmp(seg32->segname, "__TEXT") == 0) {
textva = seg32->vmaddr;
textoff = seg32->fileoff;
textsize = seg32->vmsize;
sect32 = (MachSect32*)(cmdp + sizeof(MachSeg32));
for(j = 0; j < seg32->nsects; j++, sect32++) {
if (strcmp(sect32->sectname, "__gosymtab") == 0) {
symoff = swal(sect32->offset);
symsize = swal(sect32->size);
}
if (strcmp(sect32->sectname, "__gopclntab") == 0) {
pclnoff = swal(sect32->offset);
pclnsize = swal(sect32->size);
}
}
}
if (strcmp(seg32->segname, "__DATA") == 0) {
datava = seg32->vmaddr;
dataoff = seg32->fileoff;
datasize = seg32->filesize;
bsssize = seg32->vmsize - seg32->filesize;
}
break;
case MACH_SEGMENT_64:
werrstr("MACH SEGMENT 64 NOT SUPPORTED");
goto bad;
//if(mp->magic != 0xFEEDFACF) {
// werrstr("segment 32 in mach 64");
// goto bad;
//}
//seg = (MachSeg64*)c;
//seg->vmaddr = swav(seg->vmaddr);
//seg->vmsize = swav(seg->vmsize);
//seg->fileoff = swav(seg->fileoff);
//seg->filesize = swav(seg->filesize);
//seg->maxprot = swal(seg->maxprot);
//seg->initprot = swal(seg->initprot);
//seg->nsects = swal(seg->nsects);
//seg->flags = swal(seg->flags);
//if (strcmp(seg->segname, "__TEXT") == 0) {
// textva = seg->vmaddr;
// textoff = seg->fileoff;
// textsize = seg->vmsize;
// sect = (MachSect64*)(cmdp + sizeof(MachSeg64));
// for(j = 0; j < seg->nsects; j++, sect++) {
// if (strcmp(sect->sectname, "__gosymtab") == 0) {
// symoff = swal(sect->offset);
// symsize = swal(sect->size);
// }
// if (strcmp(sect->sectname, "__gopclntab") == 0) {
// pclnoff = swal(sect->offset);
// pclnsize = swal(sect->size);
// }
// }
//}
//if (strcmp(seg->segname, "__DATA") == 0) {
// datava = seg->vmaddr;
// dataoff = seg->fileoff;
// datasize = seg->filesize;
// bsssize = seg->vmsize - seg->filesize;
//}
break;
case MACH_UNIXTHREAD:
break;
case MACH_SYMSEG:
if (symtab == 0) {
symtab = (MachSymSeg*)c;
symoff = swal(symtab->fileoff);
symsize = swal(symtab->filesize);
} else if (pclntab == 0) {
pclntab = (MachSymSeg*)c;
pclnoff = swal(pclntab->fileoff);
pclnsize = swal(pclntab->filesize);
}
break;
}
cmdp += c->size;
}
if (textva == 0 || datava == 0) {
free(cmd);
free(cmdbuf);
return 0;
}
/* compute entry by taking address after header - weird - BUG? */
settext(fp, textva+sizeof(Machhdr) + mp->sizeofcmds, textva, textsize, textoff);
setdata(fp, datava, datasize, dataoff, bsssize);
if(symoff > 0)
setsym(fp, symoff, symsize, 0, 0, pclnoff, pclnsize);
free(cmd);
free(cmdbuf);
return 1;
bad:
free(cmd);
free(cmdbuf);
return 0;
}
static int
machdotout(int fd, Fhdr *fp, ExecHdr *hp)
{
uvlong (*swav)(uvlong);
uint32 (*swal)(uint32);
ushort (*swab)(ushort);
Machhdr *mp;
MachCmd **cmd;
MachSymSeg *symtab;
MachSymSeg *pclntab;
MachSeg64 *seg;
MachSect64 *sect;
MachSeg32 *seg32;
MachSect32 *sect32;
uvlong textsize, datasize, bsssize;
uchar *cmdbuf;
uchar *cmdp;
int i, hdrsize;
uint32 textva, textoff, datava, dataoff;
mp = &hp->e.machhdr;
if (leswal(mp->filetype) != MACH_EXECUTABLE_TYPE) {
werrstr("bad MACH executable type %#ux", leswal(mp->filetype));
return 0;
}
swab = leswab;
swal = leswal;
swav = leswav;
mp->magic = swal(mp->magic);
mp->cputype = swal(mp->cputype);
mp->cpusubtype = swal(mp->cpusubtype);
mp->filetype = swal(mp->filetype);
mp->ncmds = swal(mp->ncmds);
mp->sizeofcmds = swal(mp->sizeofcmds);
mp->flags = swal(mp->flags);
mp->reserved = swal(mp->reserved);
hdrsize = 0;
switch(mp->magic) {
case 0xFEEDFACE: // 32-bit mach
if (mp->cputype != MACH_CPU_TYPE_X86) {
werrstr("bad MACH cpu type - not 386");
return 0;
}
if (mp->cpusubtype != MACH_CPU_SUBTYPE_X86) {
werrstr("bad MACH cpu subtype - not 386");
return 0;
}
if (mp->filetype != MACH_EXECUTABLE_TYPE) {
werrstr("bad MACH executable type");
return 0;
}
mach = &mi386;
fp->type = FI386;
hdrsize = 28;
break;
case 0xFEEDFACF: // 64-bit mach
if (mp->cputype != MACH_CPU_TYPE_X86_64) {
werrstr("bad MACH cpu type - not amd64");
return 0;
}
if (mp->cpusubtype != MACH_CPU_SUBTYPE_X86) {
werrstr("bad MACH cpu subtype - not amd64");
return 0;
}
mach = &mamd64;
fp->type = FAMD64;
hdrsize = 32;
break;
default:
werrstr("not mach %#ux", mp->magic);
return 0;
}
cmdbuf = malloc(mp->sizeofcmds);
seek(fd, hdrsize, 0);
if(read(fd, cmdbuf, mp->sizeofcmds) != mp->sizeofcmds) {
free(cmdbuf);
return 0;
}
cmd = malloc(mp->ncmds * sizeof(MachCmd*));
cmdp = cmdbuf;
textva = 0;
textoff = 0;
dataoff = 0;
datava = 0;
symtab = 0;
pclntab = 0;
textsize = datasize = bsssize = 0;
for (i = 0; i < mp->ncmds; i++) {
MachCmd *c;
cmd[i] = (MachCmd*)cmdp;
c = cmd[i];
c->type = swal(c->type);
c->size = swal(c->size);
switch(c->type) {
case MACH_SEGMENT_32:
if(mp->magic != 0xFEEDFACE) {
werrstr("segment 32 in mach 64");
goto bad;
}
seg32 = (MachSeg32*)c;
seg32->vmaddr = swav(seg32->vmaddr);
seg32->vmsize = swav(seg32->vmsize);
seg32->fileoff = swav(seg32->fileoff);
seg32->filesize = swav(seg32->filesize);
seg32->maxprot = swal(seg32->maxprot);
seg32->initprot = swal(seg32->initprot);
seg32->nsects = swal(seg32->nsects);
seg32->flags = swal(seg32->flags);
if (strcmp(seg32->segname, "__TEXT") == 0) {
textva = seg32->vmaddr;
textoff = seg32->fileoff;
sect32 = (MachSect32*)(cmdp + sizeof(MachSeg32));
if (strcmp(sect32->sectname, "__text") == 0) {
textsize = swal(sect32->size);
} else {
werrstr("no text section");
goto bad;
}
}
if (strcmp(seg32->segname, "__DATA") == 0) {
datava = seg32->vmaddr;
dataoff = seg32->fileoff;
sect32 = (MachSect32*)(cmdp + sizeof(MachSeg32));
if (strcmp(sect32->sectname, "__data") == 0) {
datasize = swal(sect32->size);
} else {
werrstr("no data section");
goto bad;
}
sect32++;
if (strcmp(sect32->sectname, "__nl_symbol_ptr") == 0)
sect32++;
if (strcmp(sect32->sectname, "__bss") == 0) {
bsssize = swal(sect32->size);
} else {
werrstr("no bss section");
goto bad;
}
}
break;
case MACH_SEGMENT_64:
if(mp->magic != 0xFEEDFACF) {
werrstr("segment 32 in mach 64");
goto bad;
}
seg = (MachSeg64*)c;
seg->vmaddr = swav(seg->vmaddr);
seg->vmsize = swav(seg->vmsize);
seg->fileoff = swav(seg->fileoff);
seg->filesize = swav(seg->filesize);
seg->maxprot = swal(seg->maxprot);
seg->initprot = swal(seg->initprot);
seg->nsects = swal(seg->nsects);
seg->flags = swal(seg->flags);
if (strcmp(seg->segname, "__TEXT") == 0) {
textva = seg->vmaddr;
textoff = seg->fileoff;
sect = (MachSect64*)(cmdp + sizeof(MachSeg64));
if (strcmp(sect->sectname, "__text") == 0) {
textsize = swav(sect->size);
} else {
werrstr("no text section");
goto bad;
}
}
if (strcmp(seg->segname, "__DATA") == 0) {
datava = seg->vmaddr;
dataoff = seg->fileoff;
sect = (MachSect64*)(cmdp + sizeof(MachSeg64));
if (strcmp(sect->sectname, "__data") == 0) {
datasize = swav(sect->size);
} else {
werrstr("no data section");
goto bad;
}
sect++;
if (strcmp(sect->sectname, "__bss") == 0) {
bsssize = swav(sect->size);
} else {
werrstr("no bss section");
goto bad;
}
}
break;
case MACH_UNIXTHREAD:
break;
case MACH_SYMSEG:
if (symtab == 0)
symtab = (MachSymSeg*)c;
else if (pclntab == 0)
pclntab = (MachSymSeg*)c;
break;
}
cmdp += c->size;
}
if (textva == 0 || datava == 0) {
free(cmd);
free(cmdbuf);
return 0;
}
/* compute entry by taking address after header - weird - BUG? */
settext(fp, textva+sizeof(Machhdr) + mp->sizeofcmds, textva, textsize, textoff);
setdata(fp, datava, datasize, dataoff, bsssize);
if(symtab != 0)
setsym(fp, symtab->filesize, 0, pclntab? pclntab->filesize : 0, symtab->fileoff);
free(cmd);
free(cmdbuf);
return 1;
bad:
free(cmd);
free(cmdbuf);
return 0;
}
static int
elfdotout(int fd, Fhdr *fp, ExecHdr *hp)
{
uint32 (*swal)(uint32);
ushort (*swab)(ushort);
Ehdr32 *ep;
Phdr32 *ph;
int i, it, id, is, phsz, shsz;
Shdr32 *sh;
/* bitswap the header according to the DATA format */
ep = &hp->e.elfhdr32;
if(ep->ident[CLASS] != ELFCLASS32) {
return elf64dotout(fd, fp, hp);
}
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:
mach = &msparc64;
fp->type = FSPARC64;
break;
case POWER:
mach = &mpower;
fp->type = FPOWER;
break;
case ARM:
mach = &marm;
fp->type = FARM;
break;
default:
return 0;
}
if(ep->phentsize != sizeof(Phdr32)) {
werrstr("bad ELF header size");
return 0;
}
phsz = sizeof(Phdr32)*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(uint32), swal);
shsz = sizeof(Shdr32)*ep->shnum;
sh = malloc(shsz);
if(sh) {
seek(fd, ep->shoff, 0);
if(read(fd, sh, shsz) < 0) {
free(sh);
sh = 0;
} else
hswal(sh, shsz/sizeof(uint32), 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) {
uint32 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");
error:
free(sh);
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);
else if(sh != 0){
char *buf;
uvlong symsize = 0;
uvlong symoff = 0;
uvlong pclnsz = 0;
/* load shstrtab names */
buf = malloc(sh[ep->shstrndx].size);
if (buf == 0)
goto done;
memset(buf, 0, sizeof buf);
seek(fd, sh[ep->shstrndx].offset, 0);
read(fd, buf, sh[ep->shstrndx].size);
for(i = 0; i < ep->shnum; i++) {
if (strcmp(&buf[sh[i].name], ".gosymtab") == 0) {
symsize = sh[i].size;
symoff = sh[i].offset;
}
if (strcmp(&buf[sh[i].name], ".gopclntab") == 0) {
if (sh[i].offset != symoff+symsize) {
werrstr("pc line table not contiguous with symbol table");
free(buf);
goto error;
}
pclnsz = sh[i].size;
}
}
setsym(fp, symsize, 0, pclnsz, symoff);
free(buf);
}
done:
free(sh);
free(ph);
return 1;
}
