From 48d2de7eb9a4ed30faf29abebbbbb205b308cb33 Mon Sep 17 00:00:00 2001 From: Alex Brainman Date: Wed, 19 Jan 2011 15:10:01 -0500 Subject: [PATCH] 8l: pe changes Dll names and function names padded to even size. Refactoring of imports writing code. R=rsc CC=golang-dev https://golang.org/cl/3804042 --- src/cmd/ld/pe.c | 159 ++++++++++++++++++++++-------------------------- 1 file changed, 74 insertions(+), 85 deletions(-) diff --git a/src/cmd/ld/pe.c b/src/cmd/ld/pe.c index 82c6941f251..661d3071855 100644 --- a/src/cmd/ld/pe.c +++ b/src/cmd/ld/pe.c @@ -48,21 +48,20 @@ static IMAGE_SECTION_HEADER sh[16]; typedef struct Imp Imp; struct Imp { Sym* s; - long va; - long vb; + uvlong off; Imp* next; }; typedef struct Dll Dll; struct Dll { char* name; - int count; + uvlong nameoff; + uvlong thunkoff; Imp* ms; Dll* next; }; static Dll* dr; -static int ndll, nimp, nsize; static IMAGE_SECTION_HEADER* addpesection(char *name, int sectsize, int filesize, Segment *s) @@ -136,9 +135,15 @@ pewrite(void) static void strput(char *s) { - while(*s) + int n; + + for(n=0; *s; n++) cput(*s++); cput('\0'); + n++; + // string must be padded to even size + if(n%2) + cput('\0'); } static Dll* @@ -146,50 +151,33 @@ initdynimport(void) { Imp *m; Dll *d; - Sym *s; + Sym *s, *dynamic; int i; - Sym *dynamic; dr = nil; - ndll = 0; - nimp = 0; - nsize = 0; for(i=0; ihash) { if(!s->reachable || !s->dynimpname) continue; - nimp++; for(d = dr; d != nil; d = d->next) { if(strcmp(d->name,s->dynimplib) == 0) { m = mal(sizeof *m); - m->s = s; - m->next = d->ms; - d->ms = m; - d->count++; - nsize += strlen(s->dynimpname)+2+1; break; } } if(d == nil) { d = mal(sizeof *d); d->name = s->dynimplib; - d->count = 1; d->next = dr; dr = d; m = mal(sizeof *m); - m->s = s; - m->next = 0; - d->ms = m; - ndll++; - nsize += strlen(s->dynimpname)+2+1; - nsize += strlen(s->dynimplib)+1; } + m->s = s; + m->next = d->ms; + d->ms = m; } - nsize += 20*ndll + 20; - nsize += 4*nimp + 4*ndll; - dynamic = lookup(".windynamic", 0); dynamic->reachable = 1; dynamic->type = SWINDOWS; @@ -211,83 +199,84 @@ static void addimports(vlong fileoff, IMAGE_SECTION_HEADER *datsect) { IMAGE_SECTION_HEADER *isect; - uint32 va; - int noff, aoff, o, last_fn, last_name_off, iat_off; + uvlong n, oftbase, ftbase; Imp *m; Dll *d; Sym* dynamic; - isect = addpesection(".idata", nsize, nsize, 0); + dynamic = lookup(".windynamic", 0); + + // skip import descriptor table (will write it later) + n = 0; + for(d = dr; d != nil; d = d->next) + n++; + seek(cout, fileoff + sizeof(IMAGE_IMPORT_DESCRIPTOR) * (n + 1), 0); + + // write dll names + for(d = dr; d != nil; d = d->next) { + d->nameoff = cpos() - fileoff; + strput(d->name); + } + + // write function names + for(d = dr; d != nil; d = d->next) { + for(m = d->ms; m != nil; m = m->next) { + m->off = nextsectoff + cpos() - fileoff; + wputl(0); // hint + strput(m->s->dynimpname); + } + } + + // write OriginalFirstThunks + oftbase = cpos() - fileoff; + n = cpos(); + for(d = dr; d != nil; d = d->next) { + d->thunkoff = cpos() - n; + for(m = d->ms; m != nil; m = m->next) + lputl(m->off); + lputl(0); + } + + // add pe section and pad it at the end + n = cpos() - fileoff; + isect = addpesection(".idata", n, n, 0); isect->Characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA| IMAGE_SCN_MEM_READ|IMAGE_SCN_MEM_WRITE; - va = isect->VirtualAddress; - oh.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress = va; - oh.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].Size = isect->VirtualSize; + strnput("", isect->SizeOfRawData - n); + cflush(); - seek(cout, fileoff, 0); - - dynamic = lookup(".windynamic", 0); - iat_off = dynamic->value - PEBASE; // FirstThunk allocated in .data - oh.DataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].VirtualAddress = iat_off; - oh.DataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].Size = dynamic->size; - - noff = va + 20*ndll + 20; - aoff = noff + 4*nimp + 4*ndll; - last_fn = 0; - last_name_off = aoff; + // write FirstThunks (allocated in .data section) + ftbase = dynamic->value - datsect->VirtualAddress - PEBASE; + seek(cout, datsect->PointerToRawData + ftbase, 0); for(d = dr; d != nil; d = d->next) { - lputl(noff); + for(m = d->ms; m != nil; m = m->next) + lputl(m->off); + lputl(0); + } + cflush(); + + // finally write import descriptor table + seek(cout, fileoff, 0); + for(d = dr; d != nil; d = d->next) { + lputl(isect->VirtualAddress + oftbase + d->thunkoff); lputl(0); lputl(0); - lputl(last_name_off); - lputl(iat_off); - last_fn = d->count; - noff += 4*last_fn + 4; - aoff += 4*last_fn + 4; - iat_off += 4*last_fn + 4; - last_name_off += strlen(d->name)+1; + lputl(isect->VirtualAddress + d->nameoff); + lputl(datsect->VirtualAddress + ftbase + d->thunkoff); } lputl(0); //end lputl(0); lputl(0); lputl(0); lputl(0); - - // put OriginalFirstThunk - o = last_name_off; - for(d = dr; d != nil; d = d->next) { - for(m = d->ms; m != nil; m = m->next) { - lputl(o); - o += 2 + strlen(m->s->dynimpname) + 1; - } - lputl(0); - } - // put names - for(d = dr; d != nil; d = d->next) { - strput(d->name); - } - // put hint+name - for(d = dr; d != nil; d = d->next) { - for(m = d->ms; m != nil; m = m->next) { - wputl(0); - strput(m->s->dynimpname); - } - } - - strnput("", isect->SizeOfRawData - nsize); cflush(); + + // update data directory + oh.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress = isect->VirtualAddress; + oh.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT].Size = isect->VirtualSize; + oh.DataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].VirtualAddress = dynamic->value - PEBASE; + oh.DataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].Size = dynamic->size; - // put FirstThunk - o = last_name_off; - seek(cout, datsect->PointerToRawData + dynamic->value - PEBASE - datsect->VirtualAddress, 0); - for(d = dr; d != nil; d = d->next) { - for(m = d->ms; m != nil; m = m->next) { - lputl(o); - o += 2 + strlen(m->s->dynimpname) + 1; - } - lputl(0); - } - cflush(); seek(cout, 0, 2); }