/*
This file is part of Fennix Kernel.
Fennix Kernel is free software: you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation, either version 3 of
the License, or (at your option) any later version.
Fennix Kernel is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Fennix Kernel. If not, see .
*/
#include
#include
#include
#include
#include
#include
#include
#include
#include "../../kernel.h"
using namespace Tasking;
using namespace vfs;
namespace Execute
{
void ELFObject::GenerateAuxiliaryVector(Memory::VirtualMemoryArea *vma, Node &fd, Elf_Ehdr ELFHeader, uintptr_t EntryPoint, uintptr_t BaseAddress)
{
char *aux_platform = (char *)vma->RequestPages(1, true); /* TODO: 4KiB is too much for this */
strcpy(aux_platform, "x86_64");
void *execfn_str = vma->RequestPages(TO_PAGES(fd->Path.size() + 1), true);
strcpy((char *)execfn_str, fd->Path.c_str());
void *at_random = vma->RequestPages(1, true);
*(uintptr_t *)at_random = Random::rand16();
Elfauxv.push_back({.archaux = {.a_type = AT_NULL, .a_un = {.a_val = 0}}});
Elfauxv.push_back({.archaux = {.a_type = AT_PLATFORM, .a_un = {.a_val = (uintptr_t)aux_platform}}});
Elfauxv.push_back({.archaux = {.a_type = AT_EXECFN, .a_un = {.a_val = (uintptr_t)execfn_str}}});
// AT_HWCAP2 26
Elfauxv.push_back({.archaux = {.a_type = AT_RANDOM, .a_un = {.a_val = (uintptr_t)at_random}}});
Elfauxv.push_back({.archaux = {.a_type = AT_SECURE, .a_un = {.a_val = (uintptr_t)0}}}); /* FIXME */
Elfauxv.push_back({.archaux = {.a_type = AT_EGID, .a_un = {.a_val = (uintptr_t)0}}}); /* FIXME */
Elfauxv.push_back({.archaux = {.a_type = AT_GID, .a_un = {.a_val = (uintptr_t)0}}}); /* FIXME */
Elfauxv.push_back({.archaux = {.a_type = AT_EUID, .a_un = {.a_val = (uintptr_t)0}}}); /* FIXME */
Elfauxv.push_back({.archaux = {.a_type = AT_UID, .a_un = {.a_val = (uintptr_t)0}}}); /* FIXME */
Elfauxv.push_back({.archaux = {.a_type = AT_ENTRY, .a_un = {.a_val = (uintptr_t)EntryPoint}}});
// AT_FLAGS 8
Elfauxv.push_back({.archaux = {.a_type = AT_BASE, .a_un = {.a_val = (uintptr_t)BaseAddress}}});
if (ELFProgramHeaders)
{
Elfauxv.push_back({.archaux = {.a_type = AT_PHNUM, .a_un = {.a_val = (uintptr_t)ELFHeader.e_phnum}}});
Elfauxv.push_back({.archaux = {.a_type = AT_PHENT, .a_un = {.a_val = (uintptr_t)ELFHeader.e_phentsize}}});
Elfauxv.push_back({.archaux = {.a_type = AT_PHDR, .a_un = {.a_val = (uintptr_t)ELFProgramHeaders}}});
}
// AT_CLKTCK 17
Elfauxv.push_back({.archaux = {.a_type = AT_PAGESZ, .a_un = {.a_val = (uintptr_t)PAGE_SIZE}}});
// AT_HWCAP 16
// AT_SYSINFO_EHDR 33
// AT_MINSIGSTKSZ 51
#ifdef DEBUG
for (auto var : Elfauxv)
{
debug("auxv: %ld %#lx",
var.archaux.a_type,
var.archaux.a_un.a_val);
}
#endif
}
void ELFObject::LoadSegments(Node &fd, PCB *TargetProcess, Elf_Ehdr &ELFHeader, uintptr_t &BaseAddress)
{
Memory::Virtual vmm(TargetProcess->PageTable);
Memory::VirtualMemoryArea *vma = TargetProcess->vma;
Elf_Phdr ProgramBreakHeader{};
Elf_Phdr ProgramHeader;
if (ELFHeader.e_type == ET_DYN)
{
size_t SegmentsSize = 0;
for (Elf_Half i = 0; i < ELFHeader.e_phnum; i++)
{
fs->Read(fd, &ProgramHeader, sizeof(Elf_Phdr), ELFHeader.e_phoff + (i * sizeof(Elf_Phdr)));
if (ProgramHeader.p_type == PT_LOAD || ProgramHeader.p_type == PT_DYNAMIC)
{
if (SegmentsSize < ProgramHeader.p_vaddr + ProgramHeader.p_memsz)
{
SegmentsSize = ProgramHeader.p_vaddr + ProgramHeader.p_memsz;
ProgramBreakHeader = ProgramHeader;
}
}
}
debug("SegmentsSize: %#lx", SegmentsSize);
/* TODO: Check if this is correct and/or it needs more
complex calculations & allocations */
void *SegmentsAddress = vma->RequestPages(TO_PAGES(SegmentsSize) + 1, true);
BaseAddress = (uintptr_t)SegmentsAddress;
debug("BaseAddress: %#lx, End: %#lx (%#lx)", BaseAddress, BaseAddress + FROM_PAGES(TO_PAGES(SegmentsSize)), SegmentsSize);
ProgramBreakHeader.p_vaddr += BaseAddress;
for (Elf_Half i = 0; i < ELFHeader.e_phnum; i++)
{
fs->Read(fd, &ProgramHeader, sizeof(Elf_Phdr), ELFHeader.e_phoff + (i * sizeof(Elf_Phdr)));
switch (ProgramHeader.p_type)
{
case PT_LOAD:
{
/* Because this is ET_DYN, we can load the segments
anywhere we want. */
uintptr_t SegmentDestination = BaseAddress + ProgramHeader.p_vaddr;
if (ProgramHeader.p_memsz == 0)
continue;
debug("Copying PT_LOAD to %#lx-%#lx (%ld file bytes, %ld mem bytes)",
SegmentDestination, SegmentDestination + ProgramHeader.p_memsz,
ProgramHeader.p_filesz, ProgramHeader.p_memsz);
if (ProgramHeader.p_filesz > 0)
{
fs->Read(fd, (void *)SegmentDestination, ProgramHeader.p_filesz, ProgramHeader.p_offset);
}
if (ProgramHeader.p_memsz - ProgramHeader.p_filesz > 0)
{
void *zAddr = (void *)(SegmentDestination + ProgramHeader.p_filesz);
memset(zAddr, 0, ProgramHeader.p_memsz - ProgramHeader.p_filesz);
}
break;
}
case PT_DYNAMIC:
{
/* PT_DYNAMIC contains the dynamic linking information for the
executable or shared library. */
uintptr_t DynamicSegmentDestination = BaseAddress + ProgramHeader.p_vaddr;
if (ProgramHeader.p_memsz == 0)
continue;
debug("Copying PT_DYNAMIC to %#lx-%#lx (%ld file bytes, %ld mem bytes)",
DynamicSegmentDestination, DynamicSegmentDestination + ProgramHeader.p_memsz,
ProgramHeader.p_filesz, ProgramHeader.p_memsz);
if (ProgramHeader.p_filesz > 0)
{
fs->Read(fd, (void *)DynamicSegmentDestination, ProgramHeader.p_filesz, ProgramHeader.p_offset);
}
if (ProgramHeader.p_memsz - ProgramHeader.p_filesz > 0)
{
void *zAddr = (void *)(DynamicSegmentDestination + ProgramHeader.p_filesz);
memset(zAddr, 0, ProgramHeader.p_memsz - ProgramHeader.p_filesz);
}
break;
}
case PT_PHDR:
{
ELFProgramHeaders = (void *)(BaseAddress + ProgramHeader.p_vaddr);
debug("ELFProgramHeaders: %#lx", ELFProgramHeaders);
break;
}
case 0x6474E550: /* PT_GNU_EH_FRAME */
{
fixme("PT_GNU_EH_FRAME");
break;
}
case 0x6474e551: /* PT_GNU_STACK */
{
fixme("PT_GNU_STACK");
break;
}
case 0x6474e552: /* PT_GNU_RELRO */
{
fixme("PT_GNU_RELRO");
break;
}
case 0x6474e553: /* PT_GNU_PROPERTY */
{
fixme("PT_GNU_PROPERTY");
break;
}
case PT_INTERP:
break;
default:
{
fixme("Unhandled program header type: %#lx",
ProgramHeader.p_type);
break;
}
}
}
if (!ELFProgramHeaders)
ELFProgramHeaders = (void *)(BaseAddress + ELFHeader.e_phoff);
}
else if (ELFHeader.e_type == ET_EXEC)
{
for (Elf64_Half i = 0; i < ELFHeader.e_phnum; i++)
{
fs->Read(fd, &ProgramHeader, sizeof(Elf_Phdr), ELFHeader.e_phoff + (i * sizeof(Elf_Phdr)));
switch (ProgramHeader.p_type)
{
case PT_LOAD:
{
if (ProgramHeader.p_memsz == 0)
continue;
if (BaseAddress == 0)
BaseAddress = ALIGN_DOWN(ProgramHeader.p_vaddr, PAGE_SIZE);
void *pAddr = vma->RequestPages(TO_PAGES(ProgramHeader.p_memsz + (ProgramHeader.p_vaddr % PAGE_SIZE)), true);
void *vAddr = (void *)ALIGN_DOWN(ProgramHeader.p_vaddr, PAGE_SIZE);
uintptr_t destOffset = ProgramHeader.p_vaddr - uintptr_t(vAddr);
size_t totalSize = ALIGN_UP(destOffset + ProgramHeader.p_memsz, PAGE_SIZE);
vmm.Map(vAddr, pAddr, totalSize, Memory::RW | Memory::US);
debug("Mapped %#lx-%#lx to %#lx-%#lx (%#lx bytes)",
uintptr_t(pAddr), uintptr_t(pAddr) + totalSize,
uintptr_t(vAddr), uintptr_t(vAddr) + totalSize, totalSize);
debug("Segment Offset is %#lx", destOffset);
debug("Copying PT_LOAD to p: %#lx-%#lx; v: %#lx-%#lx (%ld file bytes, %ld mem bytes)",
uintptr_t(pAddr) + destOffset,
uintptr_t(pAddr) + destOffset + ProgramHeader.p_memsz,
ProgramHeader.p_vaddr,
ProgramHeader.p_vaddr + ProgramHeader.p_memsz,
ProgramHeader.p_filesz, ProgramHeader.p_memsz);
if (ProgramHeader.p_filesz > 0)
{
debug("%d %#lx %d", ProgramHeader.p_offset, (uint8_t *)pAddr + destOffset, ProgramHeader.p_filesz);
fs->Read(fd, (uint8_t *)pAddr + destOffset, ProgramHeader.p_filesz, ProgramHeader.p_offset);
}
if (ProgramHeader.p_memsz - ProgramHeader.p_filesz > 0)
{
void *zAddr = (void *)(uintptr_t(pAddr) + destOffset + ProgramHeader.p_filesz);
debug("Zeroing %d bytes at %#lx (%#lx-%#lx)",
ProgramHeader.p_memsz - ProgramHeader.p_filesz, zAddr,
ProgramHeader.p_vaddr + ProgramHeader.p_filesz,
ProgramHeader.p_vaddr + ProgramHeader.p_memsz);
memset(zAddr, 0, ProgramHeader.p_memsz - ProgramHeader.p_filesz);
}
ProgramBreakHeader = ProgramHeader;
break;
}
case PT_NOTE:
{
Elf_Nhdr NoteHeader;
fs->Read(fd, &NoteHeader, sizeof(Elf_Nhdr), ProgramHeader.p_offset);
switch (NoteHeader.n_type)
{
case NT_PRSTATUS:
{
Elf_Prstatus prstatus;
fs->Read(fd, &prstatus, sizeof(Elf_Prstatus), ProgramHeader.p_offset + sizeof(Elf_Nhdr));
debug("PRSTATUS: %#lx", prstatus.pr_reg[0]);
break;
}
case NT_PRPSINFO:
{
Elf_Prpsinfo prpsinfo;
fs->Read(fd, &prpsinfo, sizeof(Elf_Prpsinfo), ProgramHeader.p_offset + sizeof(Elf_Nhdr));
debug("PRPSINFO: %s", prpsinfo.pr_fname);
break;
}
case NT_PLATFORM:
{
char platform[256];
fs->Read(fd, &platform, sizeof(platform), ProgramHeader.p_offset + sizeof(Elf_Nhdr));
debug("PLATFORM: %s", platform);
break;
}
case NT_AUXV:
{
Elf_auxv_t auxv;
fs->Read(fd, &auxv, sizeof(Elf_auxv_t), ProgramHeader.p_offset + sizeof(Elf_Nhdr));
debug("AUXV: %#lx", auxv.a_un.a_val);
break;
}
default:
{
fixme("Unhandled note type: %#lx", NoteHeader.n_type);
break;
}
}
break;
}
case PT_TLS:
{
size_t tlsSize = ProgramHeader.p_memsz;
debug("TLS Size: %ld (%ld pages)",
tlsSize, TO_PAGES(tlsSize));
void *tlsMemory = vma->RequestPages(TO_PAGES(tlsSize));
fs->Read(fd, tlsMemory, tlsSize, ProgramHeader.p_offset);
TargetProcess->TLS = {
.pBase = uintptr_t(tlsMemory),
.vBase = ProgramHeader.p_vaddr,
.Align = ProgramHeader.p_align,
.Size = ProgramHeader.p_memsz,
.fSize = ProgramHeader.p_filesz,
};
break;
}
case PT_PHDR:
{
ELFProgramHeaders = (void *)ProgramHeader.p_vaddr;
debug("ELFProgramHeaders: %#lx", ELFProgramHeaders);
break;
}
case PT_GNU_EH_FRAME:
{
fixme("PT_GNU_EH_FRAME");
break;
}
case PT_GNU_STACK:
{
Elf_Phdr gnuStack = ProgramHeader;
fixme("EXSTACK: %d", gnuStack.p_flags & PF_X);
break;
}
case PT_GNU_RELRO:
{
fixme("PT_GNU_RELRO");
break;
}
case PT_GNU_PROPERTY:
{
Elf_Nhdr NoteHeader;
fs->Read(fd, &NoteHeader, sizeof(Elf_Nhdr), ProgramHeader.p_offset);
if (NoteHeader.n_type == NT_GNU_PROPERTY_TYPE_0)
{
char noteName[0x400];
fs->Read(fd, noteName, NoteHeader.n_namesz, ProgramHeader.p_offset + sizeof(Elf_Nhdr));
noteName[NoteHeader.n_namesz - 1] = '\0';
if (strcmp(noteName, "GNU") == 0)
{
debug("GNU Property Note found");
}
else
{
warn("Unexpected note name in PT_GNU_PROPERTY: %s", noteName);
}
}
else
{
warn("Unhandled note type in PT_GNU_PROPERTY: %#lx", NoteHeader.n_type);
}
break;
}
case PT_INTERP:
break;
case PT_LOPROC ... PT_HIPROC:
{
debug("i guess i ignore this? %#lx", ProgramHeader.p_type);
break;
}
default:
{
fixme("Unhandled program header type: %#lx",
ProgramHeader.p_type);
break;
}
}
}
if (!ELFProgramHeaders)
fixme("ELFProgramHeaders is null");
}
/* Set program break */
uintptr_t ProgramBreak = ROUND_UP(ProgramBreakHeader.p_vaddr + ProgramBreakHeader.p_memsz, PAGE_SIZE);
TargetProcess->ProgramBreak->InitBrk(ProgramBreak);
}
void ELFObject::LoadExec(Node &fd, PCB *TargetProcess)
{
Elf_Ehdr ehdr{};
fs->Read(fd, &ehdr, sizeof(Elf_Ehdr), 0);
uintptr_t entry = ehdr.e_entry;
debug("Entry point is %#lx", entry);
Memory::Virtual vmm(TargetProcess->PageTable);
Memory::VirtualMemoryArea *vma = TargetProcess->vma;
debug("Target process page table is %#lx", TargetProcess->PageTable);
uintptr_t base = 0;
this->LoadSegments(fd, TargetProcess, ehdr, base);
debug("Entry Point: %#lx", entry);
this->GenerateAuxiliaryVector(vma, fd, ehdr, entry, 0);
this->ip = entry;
this->IsElfValid = true;
#ifdef DEBUG
std::string sanitizedPath = fd->Path;
size_t pos = sanitizedPath.find("\x06root-0\x06");
if (pos != std::string::npos)
sanitizedPath.erase(pos, std::string("\x06root-0\x06").length());
debug("gdb: \"-exec add-symbol-file-all /workspaces/Fennix/tmp_rootfs%s %#lx\" entry:%#lx", sanitizedPath.c_str(), base, entry);
#endif
}
void ELFObject::LoadDyn(Node &fd, PCB *TargetProcess)
{
Elf_Ehdr ehdr{};
fs->Read(fd, &ehdr, sizeof(Elf_Ehdr), 0);
uintptr_t entry = ehdr.e_entry;
debug("Entry point is %#lx", entry);
Memory::Virtual vmm(TargetProcess->PageTable);
Memory::VirtualMemoryArea *vma = TargetProcess->vma;
uintptr_t base = 0;
this->LoadSegments(fd, TargetProcess, ehdr, base);
entry += base;
debug("The new ep is %#lx", entry);
/* ------------------------------------------------------------------------ */
debug("Entry Point: %#lx", entry);
this->GenerateAuxiliaryVector(vma, fd, ehdr, entry, base);
this->ip = entry;
this->IsElfValid = true;
#ifdef DEBUG
std::string sanitizedPath = fd->Path;
size_t pos = sanitizedPath.find("\x06root-0\x06");
if (pos != std::string::npos)
sanitizedPath.erase(pos, std::string("\x06root-0\x06").length());
debug("gdb: \"-exec add-symbol-file-all /workspaces/Fennix/tmp_rootfs%s %#lx\" entry:%#lx", sanitizedPath.c_str(), base, entry);
#endif
std::vector interpVec = ELFGetSymbolType(fd, PT_INTERP);
if (interpVec.empty())
{
debug("No interpreter found");
return;
}
Elf_Phdr interp = interpVec.front();
std::string interpreterPath;
interpreterPath.resize(256);
fs->Read(fd, interpreterPath.data(), 256, interp.p_offset);
debug("Interpreter: %s", interpreterPath.c_str());
eNode ret = fs->Lookup(TargetProcess->Info.RootNode, interpreterPath);
if (ret == false)
{
warn("Failed to open interpreter file: %s", ret.what());
return;
}
Node ifd = ret;
if (ifd->IsSymbolicLink())
{
char buffer[512];
fs->ReadLink(ifd, buffer, sizeof(buffer));
ifd = fs->Lookup(ifd->Parent, buffer);
}
debug("ifd: %p, interpreter: %s", ifd.get(), interpreterPath.c_str());
if (GetBinaryType(interpreterPath) != BinTypeELF)
{
warn("Interpreter %s is not an ELF file", interpreterPath.c_str());
return;
}
LoadInterpreter(ifd, TargetProcess);
}
bool ELFObject::LoadInterpreter(Node &fd, PCB *TargetProcess)
{
Elf_Ehdr ehdr;
fs->Read(fd, &ehdr, sizeof(Elf_Ehdr), 0);
switch (ehdr.e_type)
{
case ET_EXEC:
assert(ehdr.e_type != ET_EXEC);
break;
case ET_DYN:
{
uintptr_t base = 0;
this->LoadSegments(fd, TargetProcess, ehdr, base);
this->ip = base + ehdr.e_entry;
for (auto &&aux : Elfauxv)
{
if (aux.archaux.a_type != AT_BASE)
continue;
aux.archaux.a_un.a_val = base;
break;
}
#ifdef DEBUG
std::string sanitizedPath = fd->Path;
size_t pos = sanitizedPath.find("\x06root-0\x06");
if (pos != std::string::npos)
sanitizedPath.erase(pos, std::string("\x06root-0\x06").length());
debug("gdb: \"-exec add-symbol-file-all /workspaces/Fennix/tmp_rootfs%s %#lx\" entry:%#lx", sanitizedPath.c_str(), base, ehdr.e_entry);
#endif
return true;
}
case ET_CORE:
case ET_REL:
case ET_NONE:
{
warn("Ignoring interpreter: %s (reason: ET_ is %#lx)", fd->Path.c_str(), ehdr.e_type);
break;
}
default:
{
error("Unknown ELF Type: %d", ehdr.e_type);
break;
}
}
return false;
}
ELFObject::ELFObject(std::string AbsolutePath, PCB *TargetProcess, const char **argv, const char **envp)
{
if (GetBinaryType(AbsolutePath) != BinaryType::BinTypeELF)
{
error("%s is not an ELF file or is invalid.", AbsolutePath.c_str());
return;
}
eNode ret = fs->Lookup(TargetProcess->Info.RootNode, AbsolutePath);
if (ret == false)
{
error("Failed to open %s, errno: %s", AbsolutePath.c_str(), ret.what());
return;
}
Node fd = ret;
if (fd->IsSymbolicLink())
{
char buffer[512];
fs->ReadLink(fd, buffer, sizeof(buffer));
fd = fs->Lookup(fd->Parent, buffer);
}
debug("Opened %s", AbsolutePath.c_str());
int argc = 0;
int envc = 0;
while (argv[argc] != nullptr)
argc++;
while (envp[envc] != nullptr)
envc++;
Elf_Ehdr ehdr{};
fs->Read(fd, &ehdr, sizeof(Elf_Ehdr), 0);
// ELFargv = new const char *[argc + 2];
size_t argv_size = argc + 2 * sizeof(char *);
ELFargv = (const char **)TargetProcess->vma->RequestPages(TO_PAGES(argv_size));
for (int i = 0; i < argc; i++)
{
size_t arg_size = strlen(argv[i]) + 1;
ELFargv[i] = (const char *)TargetProcess->vma->RequestPages(TO_PAGES(arg_size));
strcpy((char *)ELFargv[i], argv[i]);
}
ELFargv[argc] = nullptr;
// ELFenvp = new const char *[envc + 1];
size_t envp_size = envc + 1 * sizeof(char *);
ELFenvp = (const char **)TargetProcess->vma->RequestPages(TO_PAGES(envp_size));
for (int i = 0; i < envc; i++)
{
assert(envp[i] != nullptr);
size_t env_size = strlen(envp[i]) + 1;
ELFenvp[i] = (const char *)TargetProcess->vma->RequestPages(TO_PAGES(env_size));
strcpy((char *)ELFenvp[i], envp[i]);
}
ELFenvp[envc] = nullptr;
switch (ehdr.e_type)
{
case ET_REL:
{
fixme("ET_REL not implemented");
break;
}
case ET_EXEC:
{
switch (ehdr.e_machine)
{
case EM_386:
case EM_X86_64:
case EM_ARM:
case EM_AARCH64:
this->LoadExec(fd, TargetProcess);
break;
default:
error("Unknown architecture: %d", ehdr.e_machine);
break;
}
break;
}
case ET_DYN:
{
switch (ehdr.e_machine)
{
case EM_386:
case EM_X86_64:
case EM_ARM:
case EM_AARCH64:
this->LoadDyn(fd, TargetProcess);
break;
default:
error("Unknown architecture: %d", ehdr.e_machine);
break;
}
break;
}
case ET_CORE:
{
fixme("ET_CORE not implemented");
break;
}
case ET_NONE:
default:
{
error("Unknown ELF Type: %d", ehdr.e_type);
break;
}
}
}
ELFObject::~ELFObject()
{
}
}