fxos/fxos/disassembly.cpp

153 lines
3.6 KiB
C++

#include "fxos-cli.h"
#include <fxos/disassembly.h>
#include <fxos/memory.h>
#include <fxos/target.h>
#include <fxos/util.h>
#include <fxos/log.h>
#include <fxos/os.h>
#include <fxos/disasm-passes/cfg.h>
#include <fxos/disasm-passes/pcrel.h>
#include <fxos/disasm-passes/syscall.h>
#include <fxos/disasm-passes/print.h>
using namespace FxOS;
using namespace FxOS::Log;
int disassembly(Library &library, Target &target, char const *ref,
std::vector<std::string> passes)
{
Disassembly disasm(target);
int len=0;
/* Observe the target only if it has an OS mapped */
std::unique_ptr<OS> os;
if(target.covers(MemoryRegion::ROM)) os = std::make_unique<OS>(target);
/* Parameters inside the ref */
uint32_t address = -1;
uint32_t blocklen;
int syscall_id;
char blockmul[2] = { 0 };
enum { RefNone=0, RefSyscall, RefAddress, RefBlock } reftype = RefNone;
/* Parse different flavors of references. %<hexa>: syscall */
if(sscanf(ref, "%%%x", &syscall_id) == 1)
reftype = RefSyscall;
/* Pure hexa: address */
else if(sscanf(ref, "%x%n", &address, &len) == 1 && !ref[len])
reftype = RefAddress;
/* Hexa with a size: a block */
else if(sscanf(ref,"%x:%x%n",&address,&blocklen,&len)==2 && !ref[len])
reftype = RefBlock;
/* Variant of block size that includes a letter k/M/G (note that the
"%[]" specifier never matches empty strings */
else if(sscanf(ref, "%x:%x%1[kMG]%n", &address, &blocklen, blockmul,
&len) == 3 && !ref[len])
{
reftype = RefBlock;
int mul = blockmul[0];
if(mul == 'k') blocklen <<= 10;
if(mul == 'M') blocklen <<= 20;
if(mul == 'G') blocklen <<= 30;
}
/* Anything else: look up symbols */
else
{
std::string name = ref;
for(auto const &symtable: library.sym_tables())
{
std::optional<Symbol> sym = symtable.lookup(name);
if(!sym) continue;
if(sym->type == Symbol::Syscall)
reftype = RefSyscall, syscall_id = sym->value;
if(sym->type == Symbol::Address)
reftype = RefAddress, address = sym->value;
break;
}
}
/* Now try to load the address for this reference */
if(reftype == RefSyscall)
{
if(!os)
{
log(ERR "cannot disassemble syscall %s: target does "
"not have an OS mapped", ref);
return 1;
}
if(syscall_id >= os->syscall_count())
{
log(ERR "this OS only has %#x syscalls",
os->syscall_count());
return 1;
}
address = os->syscall(syscall_id);
}
if(reftype == RefAddress || reftype == RefBlock)
{
if(address & 1)
{
log(WRN "address %08x is odd, will start at %08x",
address, address+1);
address++;
}
}
if(reftype == RefBlock)
{
/* Load the block into memory */
for(uint32_t pc = address; pc < address + blocklen; pc += 2)
{
disasm.readins(pc);
}
}
if(reftype == RefNone)
{
log(ERR "cannot interpret '%s' (not a syscall id, not an "
"address, and no such symbol in library)", ref);
return 1;
}
for(auto pass: passes)
{
auto start = timer_start();
log(LOG "Running pass %s...\\", pass);
if(pass == "cfg" && reftype != RefBlock)
{
CfgPass p(disasm);
p.run(address);
}
else if(pass == "pcrel")
{
PcrelPass p(disasm);
p.run();
}
else if(pass == "syscall")
{
SyscallPass p(disasm, os.get());
p.run();
}
else if(pass == "print")
{
PrintPass p(disasm, library.sym_tables());
p.promote_pcjump_loc = PrintPass::Promote;
p.promote_pcrel_loc = PrintPass::Promote;
p.promote_pcrel_value = PrintPass::Promote;
p.promote_syscall = PrintPass::Promote;
p.promote_syscallname = PrintPass::Append;
p.promote_symbol = PrintPass::Append;
p.run();
}
log(LOG "%s", timer_format(timer_end(start)));
}
return 0;
}