libmach: support reading symbols from Windows .exe for nm
Fixes #979.
R=rsc, alex.brainman
CC=golang-dev, vcc.163
https://golang.org/cl/4894051
diff --git a/src/libmach/executable.c b/src/libmach/executable.c
index 1ad6e3b..fa0fa1b 100644
--- a/src/libmach/executable.c
+++ b/src/libmach/executable.c
@@ -66,6 +66,7 @@
static int elfdotout(int, Fhdr*, ExecHdr*);
static int machdotout(int, Fhdr*, ExecHdr*);
static int armdotout(int, Fhdr*, ExecHdr*);
+static int pedotout(int, Fhdr*, ExecHdr*);
static void setsym(Fhdr*, vlong, int32, vlong, int32, vlong, int32);
static void setdata(Fhdr*, uvlong, int32, vlong, int32);
static void settext(Fhdr*, uvlong, uvlong, int32, vlong);
@@ -312,6 +313,15 @@
sizeof(Exec),
beswal,
common },
+ { 0x4d5a9000, /* see dosstub[] in pe.c */
+ "windows PE executable",
+ nil,
+ FWINPE,
+ 0,
+ &mi386,
+ sizeof(Exec), /* TODO */
+ nil,
+ pedotout },
{ 0 },
};
@@ -1249,6 +1259,164 @@
return 1;
}
+/*
+ * Structures needed to parse PE image.
+ */
+typedef struct {
+ uint16 Machine;
+ uint16 NumberOfSections;
+ uint32 TimeDateStamp;
+ uint32 PointerToSymbolTable;
+ uint32 NumberOfSymbols;
+ uint16 SizeOfOptionalHeader;
+ uint16 Characteristics;
+} IMAGE_FILE_HEADER;
+
+typedef struct {
+ uint8 Name[8];
+ uint32 VirtualSize;
+ uint32 VirtualAddress;
+ uint32 SizeOfRawData;
+ uint32 PointerToRawData;
+ uint32 PointerToRelocations;
+ uint32 PointerToLineNumbers;
+ uint16 NumberOfRelocations;
+ uint16 NumberOfLineNumbers;
+ uint32 Characteristics;
+} IMAGE_SECTION_HEADER;
+
+typedef struct {
+ uint32 VirtualAddress;
+ uint32 Size;
+} IMAGE_DATA_DIRECTORY;
+
+typedef struct {
+ uint16 Magic;
+ uint8 MajorLinkerVersion;
+ uint8 MinorLinkerVersion;
+ uint32 SizeOfCode;
+ uint32 SizeOfInitializedData;
+ uint32 SizeOfUninitializedData;
+ uint32 AddressOfEntryPoint;
+ uint32 BaseOfCode;
+ uint32 BaseOfData;
+ uint32 ImageBase;
+ uint32 SectionAlignment;
+ uint32 FileAlignment;
+ uint16 MajorOperatingSystemVersion;
+ uint16 MinorOperatingSystemVersion;
+ uint16 MajorImageVersion;
+ uint16 MinorImageVersion;
+ uint16 MajorSubsystemVersion;
+ uint16 MinorSubsystemVersion;
+ uint32 Win32VersionValue;
+ uint32 SizeOfImage;
+ uint32 SizeOfHeaders;
+ uint32 CheckSum;
+ uint16 Subsystem;
+ uint16 DllCharacteristics;
+ uint32 SizeOfStackReserve;
+ uint32 SizeOfStackCommit;
+ uint32 SizeOfHeapReserve;
+ uint32 SizeOfHeapCommit;
+ uint32 LoaderFlags;
+ uint32 NumberOfRvaAndSizes;
+ IMAGE_DATA_DIRECTORY DataDirectory[16];
+} IMAGE_OPTIONAL_HEADER;
+
+static int
+match8(void *buf, char *cmp)
+{
+ return strncmp((char*)buf, cmp, 8) == 0;
+}
+
+/* TODO(czaplinski): 64b windows? */
+/*
+ * Read from Windows PE/COFF .exe file image.
+ */
+static int
+pedotout(int fd, Fhdr *fp, ExecHdr *hp)
+{
+ uint32 start, magic;
+ uint32 symtab, esymtab;
+ IMAGE_FILE_HEADER fh;
+ IMAGE_SECTION_HEADER sh;
+ IMAGE_OPTIONAL_HEADER oh;
+ uint8 sym[18];
+ uint32 *valp;
+ int i;
+
+ USED(hp);
+ seek(fd, 0x3c, 0);
+ if (readn(fd, &start, sizeof(start)) != sizeof(start)) {
+ werrstr("crippled PE MSDOS header");
+ return 0;
+ }
+ start = leswal(start);
+
+ seek(fd, start, 0);
+ if (readn(fd, &magic, sizeof(magic)) != sizeof(magic)) {
+ werrstr("no PE magic number found");
+ return 0;
+ }
+ if (beswal(magic) != 0x50450000) { /* "PE\0\0" */
+ werrstr("incorrect PE magic number");
+ return 0;
+ }
+
+ if (readn(fd, &fh, sizeof(fh)) != sizeof(fh)) {
+ werrstr("crippled PE File Header");
+ return 0;
+ }
+ if (fh.PointerToSymbolTable == 0) {
+ werrstr("zero pointer to COFF symbol table");
+ return 0;
+ }
+
+ if (readn(fd, &oh, sizeof(oh)) != sizeof(oh)) {
+ werrstr("crippled PE Optional Header");
+ return 0;
+ }
+
+ seek(fd, start+sizeof(magic)+sizeof(fh)+leswab(fh.SizeOfOptionalHeader), 0);
+ fp->txtaddr = fp->dataddr = 0;
+ for (i=0; i<leswab(fh.NumberOfSections); i++) {
+ if (readn(fd, &sh, sizeof(sh)) != sizeof(sh)) {
+ werrstr("could not read Section Header %d", i+1);
+ return 0;
+ }
+ if (match8(sh.Name, ".text"))
+ settext(fp, leswal(sh.VirtualAddress), leswal(oh.AddressOfEntryPoint), leswal(sh.VirtualSize), leswal(sh.PointerToRawData));
+ if (match8(sh.Name, ".data"))
+ setdata(fp, leswal(sh.VirtualAddress), leswal(sh.SizeOfRawData), leswal(sh.PointerToRawData), leswal(sh.VirtualSize)-leswal(sh.SizeOfRawData));
+ }
+ if (fp->txtaddr==0 || fp->dataddr==0) {
+ werrstr("no .text or .data");
+ return 0;
+ }
+
+ seek(fd, leswal(fh.PointerToSymbolTable), 0);
+ symtab = esymtab = 0;
+ for (i=0; i<leswal(fh.NumberOfSymbols); i++) {
+ if (readn(fd, &sym, sizeof(sym)) != sizeof(sym)) {
+ werrstr("crippled COFF symbol %d", i);
+ return 0;
+ }
+ valp = (uint32 *)&sym[8];
+ if (match8(sym, "symtab"))
+ symtab = leswal(*valp);
+ if (match8(sym, "esymtab"))
+ esymtab = leswal(*valp);
+ }
+ if (symtab==0 || esymtab==0) {
+ werrstr("no symtab or esymtab in COFF symbol table");
+ return 0;
+ }
+ setsym(fp, symtab, esymtab-symtab, 0, 0, 0, 0);
+
+ return 1;
+}
+
static void
settext(Fhdr *fp, uvlong e, uvlong a, int32 s, vlong off)
{
