tlibmach: more mach-o support - plan9port - [fork] Plan 9 from user space
(HTM) git clone git://src.adamsgaard.dk/plan9port
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(DIR) LICENSE
---
(DIR) commit 873e5f5094b404c7ac62830341eca4eacf8b4afa
(DIR) parent 875351f44f2fa7d79e3cd69ef8862cb9c822ab66
(HTM) Author: Russ Cox <rsc@swtch.com>
Date: Fri, 24 Sep 2010 12:25:25 -0400
libmach: more mach-o support
R=rsc
http://codereview.appspot.com/2277041
Diffstat:
M src/libmach/LICENSE | 1 +
M src/libmach/crackmacho.c | 4 ++--
M src/libmach/macho.c | 244 +++++++++++++++++++++++++++++--
M src/libmach/macho.h | 126 +++++++++++++++++++++++++------
M src/libmach/mkfile | 3 +++
5 files changed, 343 insertions(+), 35 deletions(-)
---
(DIR) diff --git a/src/libmach/LICENSE b/src/libmach/LICENSE
t@@ -11,6 +11,7 @@ file such as NOTICE, LICENCE or COPYING.
Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com).
Revisions Copyright © 2000-2004 Lucent Technologies Inc. and others.
Portions Copyright © 2001-2007 Russ Cox.
+ Portions Copyright © 2008-2010 Google Inc.
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
(DIR) diff --git a/src/libmach/crackmacho.c b/src/libmach/crackmacho.c
t@@ -115,8 +115,8 @@ crackmacho(int fd, Fhdr *fp)
if(m->cmd[i].type == MachoCmdSymtab)
break;
if(i < m->ncmd){
- fp->stabs.stabbase = load(fp->fd, m->cmd[i].sym.symoff, m->cmd[i].sym.nsyms*16);
- fp->stabs.stabsize = m->cmd[i].sym.nsyms*16;
+ fp->stabs.stabbase = load(fp->fd, m->cmd[i].sym.symoff, m->cmd[i].sym.nsym*16);
+ fp->stabs.stabsize = m->cmd[i].sym.nsym*16;
fp->stabs.strbase = (char*)load(fp->fd, m->cmd[i].sym.stroff, m->cmd[i].sym.strsize);
if(fp->stabs.stabbase == nil || fp->stabs.strbase == nil){
fp->stabs.stabbase = nil;
(DIR) diff --git a/src/libmach/macho.c b/src/libmach/macho.c
t@@ -6,6 +6,27 @@
/*
http://www.channelu.com/NeXT/NeXTStep/3.3/nd/DevTools/14_MachO/MachO.htmld/
*/
+static long
+preadn(int fd, void *vdata, uint32 ulen, uint64 offset)
+{
+ long n;
+ uchar *data;
+ long len;
+
+ len = ulen;
+ data = vdata;
+/* fprint(2, "readn 0x%llux 0x%ux\n", offset, ulen); */
+ while(len > 0){
+ n = pread(fd, data, len, offset);
+ if(n <= 0)
+ break;
+ data += n;
+ offset += n;
+ len -= n;
+ }
+ return data-(uchar*)vdata;
+}
+
Macho*
machoopen(char *name)
t@@ -22,11 +43,15 @@ machoopen(char *name)
}
static int
-unpackseg(uchar *p, Macho *m, MachoCmd *c, uint type, uint sz)
+unpackcmd(uchar *p, Macho *m, MachoCmd *c, uint type, uint sz)
{
- u32int (*e4)(uchar*);
+ uint32 (*e4)(uchar*);
+ uint64 (*e8)(uchar*);
+ MachoSect *s;
+ int i;
e4 = m->e4;
+ e8 = m->e8;
c->type = type;
c->size = sz;
t@@ -45,59 +70,257 @@ unpackseg(uchar *p, Macho *m, MachoCmd *c, uint type, uint sz)
c->seg.initprot = e4(p+44);
c->seg.nsect = e4(p+48);
c->seg.flags = e4(p+52);
+ c->seg.sect = mallocz(c->seg.nsect * sizeof c->seg.sect[0], 1);
+ if(c->seg.sect == nil)
+ return -1;
+ if(sz < 56+c->seg.nsect*68)
+ return -1;
+ p += 56;
+ for(i=0; i<c->seg.nsect; i++) {
+ s = &c->seg.sect[i];
+ strecpy(s->name, s->name+sizeof s->name, (char*)p+0);
+ strecpy(s->segname, s->segname+sizeof s->segname, (char*)p+16);
+ s->addr = e4(p+32);
+ s->size = e4(p+36);
+ s->offset = e4(p+40);
+ s->align = e4(p+44);
+ s->reloff = e4(p+48);
+ s->nreloc = e4(p+52);
+ s->flags = e4(p+56);
+ // p+60 and p+64 are reserved
+ p += 68;
+ }
+ break;
+ case MachoCmdSegment64:
+ if(sz < 72)
+ return -1;
+ strecpy(c->seg.name, c->seg.name+sizeof c->seg.name, (char*)p+8);
+ c->seg.vmaddr = e8(p+24);
+ c->seg.vmsize = e8(p+32);
+ c->seg.fileoff = e8(p+40);
+ c->seg.filesz = e8(p+48);
+ c->seg.maxprot = e4(p+56);
+ c->seg.initprot = e4(p+60);
+ c->seg.nsect = e4(p+64);
+ c->seg.flags = e4(p+68);
+ c->seg.sect = mallocz(c->seg.nsect * sizeof c->seg.sect[0], 1);
+ if(c->seg.sect == nil)
+ return -1;
+ if(sz < 72+c->seg.nsect*80)
+ return -1;
+ p += 72;
+ for(i=0; i<c->seg.nsect; i++) {
+ s = &c->seg.sect[i];
+ strecpy(s->name, s->name+sizeof s->name, (char*)p+0);
+ strecpy(s->segname, s->segname+sizeof s->segname, (char*)p+16);
+ s->addr = e8(p+32);
+ s->size = e8(p+40);
+ s->offset = e4(p+48);
+ s->align = e4(p+52);
+ s->reloff = e4(p+56);
+ s->nreloc = e4(p+60);
+ s->flags = e4(p+64);
+ // p+68, p+72, and p+76 are reserved
+ p += 80;
+ }
break;
case MachoCmdSymtab:
if(sz < 24)
return -1;
c->sym.symoff = e4(p+8);
- c->sym.nsyms = e4(p+12);
+ c->sym.nsym = e4(p+12);
c->sym.stroff = e4(p+16);
c->sym.strsize = e4(p+20);
break;
+ case MachoCmdDysymtab:
+ if(sz < 80)
+ return -1;
+ c->dsym.ilocalsym = e4(p+8);
+ c->dsym.nlocalsym = e4(p+12);
+ c->dsym.iextdefsym = e4(p+16);
+ c->dsym.nextdefsym = e4(p+20);
+ c->dsym.iundefsym = e4(p+24);
+ c->dsym.nundefsym = e4(p+28);
+ c->dsym.tocoff = e4(p+32);
+ c->dsym.ntoc = e4(p+36);
+ c->dsym.modtaboff = e4(p+40);
+ c->dsym.nmodtab = e4(p+44);
+ c->dsym.extrefsymoff = e4(p+48);
+ c->dsym.nextrefsyms = e4(p+52);
+ c->dsym.indirectsymoff = e4(p+56);
+ c->dsym.nindirectsyms = e4(p+60);
+ c->dsym.extreloff = e4(p+64);
+ c->dsym.nextrel = e4(p+68);
+ c->dsym.locreloff = e4(p+72);
+ c->dsym.nlocrel = e4(p+76);
+ break;
+ }
+ return 0;
+}
+
+int
+macholoadrel(Macho *m, MachoSect *sect)
+{
+ MachoRel *rel, *r;
+ uchar *buf, *p;
+ int i, n;
+ uint32 v;
+
+ if(sect->rel != nil || sect->nreloc == 0)
+ return 0;
+ rel = mallocz(sect->nreloc * sizeof r[0], 1);
+ if(rel == nil)
+ return -1;
+ n = sect->nreloc * 8;
+ buf = mallocz(n, 1);
+ if(buf == nil) {
+ free(rel);
+ return -1;
}
+ if(seek(m->fd, sect->reloff, 0) < 0 || readn(m->fd, buf, n) != n) {
+ free(rel);
+ free(buf);
+ return -1;
+ }
+ for(i=0; i<sect->nreloc; i++) {
+ r = &rel[i];
+ p = buf+i*8;
+ r->addr = m->e4(p);
+
+ // TODO(rsc): Wrong interpretation for big-endian bitfields?
+ v = m->e4(p+4);
+ r->symnum = v & 0xFFFFFF;
+ v >>= 24;
+ r->pcrel = v&1;
+ v >>= 1;
+ r->length = 1<<(v&3);
+ v >>= 2;
+ r->extrn = v&1;
+ v >>= 1;
+ r->type = v;
+ }
+ sect->rel = rel;
+ free(buf);
return 0;
}
+int
+macholoadsym(Macho *m, MachoSymtab *symtab)
+{
+ char *strbuf;
+ uchar *symbuf, *p;
+ int i, n, symsize;
+ MachoSym *sym, *s;
+ uint32 v;
+
+ if(symtab->sym != nil)
+ return 0;
+
+ strbuf = mallocz(symtab->strsize, 1);
+ if(strbuf == nil)
+ return -1;
+ if(seek(m->fd, symtab->stroff, 0) < 0 || readn(m->fd, strbuf, symtab->strsize) != symtab->strsize) {
+ free(strbuf);
+ return -1;
+ }
+
+ symsize = 12;
+ if(m->is64)
+ symsize = 16;
+ n = symtab->nsym * symsize;
+ symbuf = mallocz(n, 1);
+ if(symbuf == nil) {
+ free(strbuf);
+ return -1;
+ }
+ if(seek(m->fd, symtab->symoff, 0) < 0 || readn(m->fd, symbuf, n) != n) {
+ free(strbuf);
+ free(symbuf);
+ return -1;
+ }
+ sym = mallocz(symtab->nsym * sizeof sym[0], 1);
+ if(sym == nil) {
+ free(strbuf);
+ free(symbuf);
+ return -1;
+ }
+ p = symbuf;
+ for(i=0; i<symtab->nsym; i++) {
+ s = &sym[i];
+ v = m->e4(p);
+ if(v >= symtab->strsize) {
+ free(strbuf);
+ free(symbuf);
+ free(sym);
+ return -1;
+ }
+ s->name = strbuf + v;
+ s->type = p[4];
+ s->sectnum = p[5];
+ s->desc = m->e2(p+6);
+ if(m->is64)
+ s->value = m->e8(p+8);
+ else
+ s->value = m->e4(p+8);
+ p += symsize;
+ }
+ symtab->str = strbuf;
+ symtab->sym = sym;
+ free(symbuf);
+ return 0;
+}
Macho*
machoinit(int fd)
{
- int i;
+ int i, is64;
uchar hdr[7*4], *cmdp;
- u32int (*e4)(uchar*);
+ uchar tmp[4];
+ uint16 (*e2)(uchar*);
+ uint32 (*e4)(uchar*);
+ uint64 (*e8)(uchar*);
ulong ncmd, cmdsz, ty, sz, off;
Macho *m;
if(seek(fd, 0, 0) < 0 || readn(fd, hdr, sizeof hdr) != sizeof hdr)
return nil;
- if(beload4(hdr) == 0xFEEDFACE)
+ if((beload4(hdr)&~1) == 0xFEEDFACE){
+ e2 = beload2;
e4 = beload4;
- else if(leload4(hdr) == 0xFEEDFACE)
+ e8 = beload8;
+ }else if((leload4(hdr)&~1) == 0xFEEDFACE){
+ e2 = leload2;
e4 = leload4;
- else{
+ e8 = leload8;
+ }else{
werrstr("bad magic - not mach-o file");
return nil;
}
-
+ is64 = e4(hdr) == 0xFEEDFACF;
ncmd = e4(hdr+4*4);
cmdsz = e4(hdr+5*4);
if(ncmd > 0x10000 || cmdsz >= 0x01000000){
werrstr("implausible mach-o header ncmd=%lud cmdsz=%lud", ncmd, cmdsz);
return nil;
}
+ if(is64)
+ readn(fd, tmp, 4); // skip reserved word in header
m = mallocz(sizeof(*m)+ncmd*sizeof(MachoCmd)+cmdsz, 1);
if(m == nil)
return nil;
m->fd = fd;
+ m->e2 = e2;
m->e4 = e4;
+ m->e8 = e8;
m->cputype = e4(hdr+1*4);
m->subcputype = e4(hdr+2*4);
m->filetype = e4(hdr+3*4);
m->ncmd = ncmd;
m->flags = e4(hdr+6*4);
+ m->is64 = is64;
m->cmd = (MachoCmd*)(m+1);
off = sizeof hdr;
t@@ -112,11 +335,10 @@ machoinit(int fd)
ty = e4(cmdp);
sz = e4(cmdp+4);
m->cmd[i].off = off;
- unpackseg(cmdp, m, &m->cmd[i], ty, sz);
+ unpackcmd(cmdp, m, &m->cmd[i], ty, sz);
cmdp += sz;
off += sz;
}
-
return m;
}
(DIR) diff --git a/src/libmach/macho.h b/src/libmach/macho.h
t@@ -1,11 +1,18 @@
typedef struct Macho Macho;
typedef struct MachoCmd MachoCmd;
+typedef struct MachoSeg MachoSeg;
+typedef struct MachoSect MachoSect;
+typedef struct MachoRel MachoRel;
+typedef struct MachoSymtab MachoSymtab;
+typedef struct MachoSym MachoSym;
+typedef struct MachoDysymtab MachoDysymtab;
enum
{
MachoCpuVax = 1,
MachoCpu68000 = 6,
MachoCpu386 = 7,
+ MachoCpuAmd64 = 0x1000007,
MachoCpuMips = 8,
MachoCpu98000 = 10,
MachoCpuHppa = 11,
t@@ -20,6 +27,8 @@ enum
MachoCmdSymtab = 2,
MachoCmdSymseg = 3,
MachoCmdThread = 4,
+ MachoCmdDysymtab = 11,
+ MachoCmdSegment64 = 25,
MachoFileObject = 1,
MachoFileExecutable = 2,
t@@ -28,40 +37,111 @@ enum
MachoFilePreload = 5
};
+struct MachoSeg
+{
+ char name[16+1];
+ uint64 vmaddr;
+ uint64 vmsize;
+ uint32 fileoff;
+ uint32 filesz;
+ uint32 maxprot;
+ uint32 initprot;
+ uint32 nsect;
+ uint32 flags;
+ MachoSect *sect;
+};
+
+struct MachoSect
+{
+ char name[16+1];
+ char segname[16+1];
+ uint64 addr;
+ uint64 size;
+ uint32 offset;
+ uint32 align;
+ uint32 reloff;
+ uint32 nreloc;
+ uint32 flags;
+
+ MachoRel *rel;
+};
+
+struct MachoRel
+{
+ uint32 addr;
+ uint32 symnum;
+ uint8 pcrel;
+ uint8 length;
+ uint8 extrn;
+ uint8 type;
+};
+
+struct MachoSymtab
+{
+ uint32 symoff;
+ uint32 nsym;
+ uint32 stroff;
+ uint32 strsize;
+
+ char *str;
+ MachoSym *sym;
+};
+
+struct MachoSym
+{
+ char *name;
+ uint8 type;
+ uint8 sectnum;
+ uint16 desc;
+ char kind;
+ uint64 value;
+};
+
+struct MachoDysymtab
+{
+ uint32 ilocalsym;
+ uint32 nlocalsym;
+ uint32 iextdefsym;
+ uint32 nextdefsym;
+ uint32 iundefsym;
+ uint32 nundefsym;
+ uint32 tocoff;
+ uint32 ntoc;
+ uint32 modtaboff;
+ uint32 nmodtab;
+ uint32 extrefsymoff;
+ uint32 nextrefsyms;
+ uint32 indirectsymoff;
+ uint32 nindirectsyms;
+ uint32 extreloff;
+ uint32 nextrel;
+ uint32 locreloff;
+ uint32 nlocrel;
+};
+
struct MachoCmd
{
int type;
- ulong off;
- ulong size;
- struct {
- char name[16+1];
- ulong vmaddr;
- ulong vmsize;
- ulong fileoff;
- ulong filesz;
- ulong maxprot;
- ulong initprot;
- ulong nsect;
- ulong flags;
- } seg;
- struct {
- ulong symoff;
- ulong nsyms;
- ulong stroff;
- ulong strsize;
- } sym;
+ uint32 off;
+ uint32 size;
+ MachoSeg seg;
+ MachoSymtab sym;
+ MachoDysymtab dsym;
};
struct Macho
{
int fd;
+ int is64;
uint cputype;
uint subcputype;
- ulong filetype;
- ulong flags;
+ uint32 filetype;
+ uint32 flags;
MachoCmd *cmd;
uint ncmd;
- u32int (*e4)(uchar*);
+ uint16 (*e2)(uchar*);
+ uint32 (*e4)(uchar*);
+ uint64 (*e8)(uchar*);
int (*coreregs)(Macho*, uchar**);
};
t@@ -69,3 +149,5 @@ Macho *machoopen(char*);
Macho *machoinit(int);
void machoclose(Macho*);
int coreregsmachopower(Macho*, uchar**);
+int macholoadrel(Macho*, MachoSect*);
+int macholoadsym(Macho*, MachoSymtab*);
(DIR) diff --git a/src/libmach/mkfile b/src/libmach/mkfile
t@@ -71,6 +71,9 @@ elfnm: elfnm.o $LIBDIR/$LIB
demangler: demangler.o $LIBDIR/$LIB
$LD -o $target $prereq -l9
+machodump: machodump.o $LIBDIR/$LIB
+ $LD -o $target $prereq -l9
+
SunOS.$O: nosys.c
Darwin.$O: nosys.c