Call like instructions (#2261)

* Move syscall number evaluation into instruction.py. This allows us to determine and display future syscalls

* Move string manipulation to color.disasm.py

* lint

* fix padding

* Fix x86 syscall

* disable debug mode

* @override decorator added to methods

* comments

* lint

* Fix x86/x86_64 edge cases with syscall register reading, and add test for emulation off for syscalls

* Tests depend on width of context banner

* Fix strange rebasing error

* Call like instructions

* Add IRET to jump groups, and remove multiple places in codebase where jumps groups are defined (non uniformly)

* remove duplicate test (rebase stuff)

* lint

pwndbg/arguments.py

@@ -9,7 +9,6 @@ from typing import List
 from typing import Tuple
 
 import gdb
-from capstone import CS_GRP_CALL
 from capstone import CS_GRP_INT
 
 import pwndbg.chain
@@ -73,7 +72,7 @@ def get(instruction: PwndbgInstruction) -> List[Tuple[pwndbg.lib.functions.Argum
     if instruction.address != pwndbg.gdblib.regs.pc:
         return []
 
-    if CS_GRP_CALL in instruction.groups:
+    if instruction.call_like:
         try:
             abi = pwndbg.lib.abi.ABI.default()
         except KeyError:

pwndbg/color/disasm.py

@@ -2,8 +2,6 @@ from __future__ import annotations
 
 from typing import List
 
-import capstone
-
 import pwndbg.chain
 import pwndbg.color.context as C
 from pwndbg.color import ColorConfig
@@ -11,11 +9,10 @@ from pwndbg.color import ColorParamSpec
 from pwndbg.color import ljust_colored
 from pwndbg.color import strip
 from pwndbg.color.message import on
+from pwndbg.gdblib.disasm.instruction import ALL_JUMP_GROUPS
 from pwndbg.gdblib.disasm.instruction import InstructionCondition
 from pwndbg.gdblib.disasm.instruction import PwndbgInstruction
 
-capstone_branch_groups = {capstone.CS_GRP_CALL, capstone.CS_GRP_JUMP}
-
 c = ColorConfig(
     "disasm",
     [
@@ -33,7 +30,7 @@ def one_instruction(ins: PwndbgInstruction) -> str:
     if pwndbg.config.highlight_pc and ins.address == pwndbg.gdblib.regs.pc:
         asm = C.highlight(asm)
 
-    is_call_or_jump = ins.groups_set & capstone_branch_groups
+    is_call_or_jump = ins.groups_set & ALL_JUMP_GROUPS
 
     # Style the instruction mnemonic if it's a call/jump instruction.
     if is_call_or_jump:

pwndbg/emu/emulator.py

@@ -676,8 +676,6 @@ class Emulator:
         debug(DEBUG_MEM_READ, "uc.mem_read(*%r, **%r)", (a, kw))
         return self.uc.mem_read(*a, **kw)
 
-    jump_types = {C.CS_GRP_CALL, C.CS_GRP_JUMP, C.CS_GRP_RET}
-
     def until_jump(self, pc=None):
         """
         Emulates instructions starting at the specified address until the
@@ -739,7 +737,7 @@ class Emulator:
     def until_call(self, pc=None):
         addr, target = self.until_jump(pc)
 
-        while target and C.CS_GRP_CALL not in pwndbg.gdblib.disasm.one_raw(addr).groups:
+        while target and not pwndbg.gdblib.disasm.one_raw(addr).call_like:
             addr, target = self.until_jump(target)
 
         return addr, target

pwndbg/gdblib/disasm/arch.py

@@ -17,6 +17,7 @@ import pwndbg.gdblib.typeinfo
 import pwndbg.gdblib.vmmap
 import pwndbg.lib.config
 from pwndbg.emu.emulator import Emulator
+from pwndbg.gdblib.disasm.instruction import FORWARD_JUMP_GROUP
 from pwndbg.gdblib.disasm.instruction import EnhancedOperand
 from pwndbg.gdblib.disasm.instruction import InstructionCondition
 from pwndbg.gdblib.disasm.instruction import PwndbgInstruction
@@ -222,7 +223,7 @@ class DisassemblyAssistant:
 
         # Disable emulation after CALL instructions. We do it after enhancement, as we can use emulation
         # to determine the call's target address.
-        if jump_emu and CS_GRP_CALL in set(instruction.groups):
+        if jump_emu and instruction.call_like:
             jump_emu.valid = False
             jump_emu = None
             emu = None
@@ -600,10 +601,7 @@ class DisassemblyAssistant:
             # Use emulator to determine the next address:
             # 1. Only use it to determine non-call's (`nexti` should step over calls)
             # 2. Make sure we haven't manually set .condition to False (which should override the emulators prediction)
-            if (
-                CS_GRP_CALL not in instruction.groups_set
-                and instruction.condition != InstructionCondition.FALSE
-            ):
+            if not instruction.call_like and instruction.condition != InstructionCondition.FALSE:
                 next_addr = jump_emu.pc
 
         # All else fails, take the next instruction in memory
@@ -641,10 +639,10 @@ class DisassemblyAssistant:
         "call" specifies if we allow this to resolve call instruction targets
         """
 
-        if CS_GRP_CALL in instruction.groups:
+        if instruction.call_like:
             if not call:
                 return None
-        elif CS_GRP_JUMP not in instruction.groups:
+        elif not bool(instruction.groups_set & FORWARD_JUMP_GROUP):
             return None
 
         addr = None

pwndbg/gdblib/disasm/instruction.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import typing
+from collections import defaultdict
 from enum import Enum
 from typing import Dict
 from typing import List
@@ -28,6 +29,7 @@ from capstone.arm64 import ARM64_INS_BLR
 from capstone.arm64 import ARM64_INS_BR
 from capstone.mips import MIPS_INS_B
 from capstone.mips import MIPS_INS_BAL
+from capstone.mips import MIPS_INS_BLTZAL
 from capstone.mips import MIPS_INS_J
 from capstone.mips import MIPS_INS_JAL
 from capstone.mips import MIPS_INS_JALR
@@ -64,13 +66,24 @@ UNCONDITIONAL_JUMP_INSTRUCTIONS: Dict[int, Set[int]] = {
     CS_ARCH_PPC: {PPC_INS_B, PPC_INS_BA, PPC_INS_BL, PPC_INS_BLA},
 }
 
+BRANCH_AND_LINK_INSTRUCTIONS: Dict[int, Set[int]] = defaultdict(set)
+BRANCH_AND_LINK_INSTRUCTIONS[CS_ARCH_MIPS] = {
+    MIPS_INS_BAL,
+    MIPS_INS_BLTZAL,
+    MIPS_INS_JAL,
+    MIPS_INS_JALR,
+}
+
 # Everything that is a CALL or a RET is a unconditional jump
-GENERIC_UNCONDITIONAL_JUMP_GROUPS = {CS_GRP_CALL, CS_GRP_RET}
+GENERIC_UNCONDITIONAL_JUMP_GROUPS = {CS_GRP_CALL, CS_GRP_RET, CS_GRP_IRET}
 # All branch-like instructions - jumps thats are non-call and non-ret - should have one of these two groups in Capstone
 GENERIC_JUMP_GROUPS = {CS_GRP_JUMP, CS_GRP_BRANCH_RELATIVE}
 # All Capstone jumps should have at least one of these groups
 ALL_JUMP_GROUPS = GENERIC_JUMP_GROUPS | GENERIC_UNCONDITIONAL_JUMP_GROUPS
 
+# All non-ret jumps
+FORWARD_JUMP_GROUP = {CS_GRP_CALL} | GENERIC_JUMP_GROUPS
+
 
 class InstructionCondition(Enum):
     # Conditional instruction, and action is taken
@@ -244,6 +257,18 @@ class PwndbgInstruction:
         If the enhancement successfully used emulation for this instruction
         """
 
+    @property
+    def call_like(self) -> bool:
+        """
+        True if this is a call-like instruction, meaning either it's a CALL or a branch and link.
+
+        Checking for the CS_GRP_CALL is insufficient, as there are many "branch and link" instructions that are not labeled as a call
+        """
+        return (
+            CS_GRP_CALL in self.groups_set
+            or self.id in BRANCH_AND_LINK_INSTRUCTIONS[self.cs_insn._cs.arch]
+        )
+
     @property
     def can_change_instruction_pointer(self) -> bool:
         """

pwndbg/gdblib/next.py

@@ -16,8 +16,7 @@ import pwndbg.gdblib.events
 import pwndbg.gdblib.proc
 import pwndbg.gdblib.regs
 from pwndbg.color import message
-
-jumps = {capstone.CS_GRP_CALL, capstone.CS_GRP_JUMP, capstone.CS_GRP_RET, capstone.CS_GRP_IRET}
+from pwndbg.gdblib.disasm.instruction import ALL_JUMP_GROUPS
 
 interrupts = {capstone.CS_GRP_INT}
 
@@ -45,10 +44,9 @@ def next_int(address=None):
 
     ins = pwndbg.gdblib.disasm.one(address)
     while ins:
-        ins_groups = set(ins.groups)
-        if ins_groups & jumps:
+        if ins.groups_set & ALL_JUMP_GROUPS:
             return None
-        elif ins_groups & interrupts:
+        elif ins.groups_set & interrupts:
             return ins
         ins = pwndbg.gdblib.disasm.one(ins.next)
 
@@ -64,7 +62,7 @@ def next_branch(address=None):
 
     ins = pwndbg.gdblib.disasm.one(address)
     while ins:
-        if set(ins.groups) & jumps:
+        if ins.groups_set & ALL_JUMP_GROUPS:
             return ins
         ins = pwndbg.gdblib.disasm.one(ins.next)
 
@@ -104,7 +102,7 @@ def next_matching_until_branch(address=None, mnemonic=None, op_str=None):
         if mnemonic_match and op_str_match:
             return ins
 
-        if set(ins.groups) & jumps:
+        if ins.groups_set & ALL_JUMP_GROUPS:
             # No matching instruction until the next branch, and we're
             # not trying to match the branch instruction itself.
             return None
@@ -145,7 +143,7 @@ def break_next_call(symbol_regex=None):
             break
 
         # continue if not a call
-        if capstone.CS_GRP_CALL not in ins.groups:
+        if not ins.call_like:
             continue
 
         # return call if we: