Compact, [big-endian] hexdump (#839)

* Add options for compact hexdump

* Minor cleanup

* Update pwndbg/commands/hexdump.py

* Update pwndbg/commands/hexdump.py

Co-authored-by: git <git@example.org>
Co-authored-by: Disconnect3d <dominik.b.czarnota@gmail.com>

pwndbg/color/hexdump.py

@@ -12,6 +12,9 @@ config_special   = theme.ColoredParameter('hexdump-special-color', 'yellow', 'co
 config_offset    = theme.ColoredParameter('hexdump-offset-color', 'none', 'color for hexdump command (offset label)')
 config_address   = theme.ColoredParameter('hexdump-address-color', 'none', 'color for hexdump command (address label)')
 config_separator = theme.ColoredParameter('hexdump-separator-color', 'none', 'color for hexdump command (group separator)')
+config_highlight_group_lsb = theme.Parameter('hexdump-highlight-group-lsb', 'underline',
+                                             'highlight LSB of each group. Applies only if hexdump-adjust-group-endianess'
+                                             ' actually changes byte order.')
 
 def normal(x):
     return generateColorFunction(config.hexdump_normal_color)(x)
@@ -33,3 +36,6 @@ def address(x):
 
 def separator(x):
     return generateColorFunction(config.hexdump_separator_color)(x)
+
+def highlight_group_lsb(x):
+    return generateColorFunction(config.hexdump_highlight_group_lsb)(x)

pwndbg/commands/hexdump.py

@@ -17,6 +17,13 @@ pwndbg.config.Parameter('hexdump-width',
 pwndbg.config.Parameter('hexdump-bytes',
                          64,
                          'number of bytes printed by hexdump command')
+pwndbg.config.Parameter('hexdump-group-width',
+                         4,
+                         "number of bytes grouped in hexdump command (If -1, the architecture's pointer size is used)")
+pwndbg.config.Parameter('hexdump-group-use-big-endian',
+                         False,
+                         'Use big-endian within each group of bytes. Only applies to raw bytes, not the ASCII part. '
+                         'See also hexdump-highlight-group-lsb.')
 
 def address_or_module_name(s):
     gdbval_or_str = pwndbg.commands.sloppy_gdb_parse(s)
@@ -50,10 +57,13 @@ def hexdump(address_or_module=None, count=pwndbg.config.hexdump_bytes):
     else:
         hexdump.offset = 0
 
-    address = int(address)
-    address &= pwndbg.arch.ptrmask
-    count   = max(int(count), 0)
-    width   = int(pwndbg.config.hexdump_width)
+    address     = int(address)
+    address     &= pwndbg.arch.ptrmask
+    count       = max(int(count), 0)
+    width       = int(pwndbg.config.hexdump_width)
+    group_width = int(pwndbg.config.hexdump_group_width)
+    group_width = pwndbg.typeinfo.ptrsize if group_width == -1 else group_width
+    flip_group_endianess = pwndbg.config.hexdump_group_use_big_endian and pwndbg.arch.endian == 'little'
 
     if count > address > 0x10000:
         count -= address
@@ -65,7 +75,7 @@ def hexdump(address_or_module=None, count=pwndbg.config.hexdump_bytes):
         print(e)
         return
 
-    for i, line in enumerate(pwndbg.hexdump.hexdump(data, address=address, width=width, offset=hexdump.offset)):
+    for i, line in enumerate(pwndbg.hexdump.hexdump(data, address=address, width=width, group_width=group_width, flip_group_endianess=flip_group_endianess, offset=hexdump.offset)):
         print(line)
     hexdump.offset += i
 

pwndbg/hexdump.py

@@ -23,6 +23,8 @@ def groupby(array, count, fill=None):
 
 config_colorize_ascii = theme.Parameter('hexdump-colorize-ascii', True, 'whether to colorize the hexdump command ascii section')
 config_separator      = theme.Parameter('hexdump-ascii-block-separator', '│', 'block separator char of the hexdump command')
+config_byte_separator = theme.Parameter('hexdump-byte-separator', ' ', 'separator of single bytes in hexdump (does NOT affect group separator)')
+
 
 @pwndbg.config.Trigger([H.config_normal, H.config_zero, H.config_special, H.config_printable, config_colorize_ascii])
 def load_color_scheme():
@@ -49,7 +51,7 @@ def load_color_scheme():
     color_scheme[-1] = '  '
     printable[-1] = ' '
 
-def hexdump(data, address = 0, width = 16, skip = True, offset = 0):
+def hexdump(data, address = 0, width = 16, group_width=4, flip_group_endianess = False, skip = True, offset = 0):
     if not color_scheme or not printable:
         load_color_scheme()
     data = list(bytearray(data))
@@ -73,14 +75,19 @@ def hexdump(data, address = 0, width = 16, skip = True, offset = 0):
 
         hexline.append(H.address("%#08x  " % (base + (i * width))))
 
-        for group in groupby(line, 4):
-            for char in group:
-                hexline.append(color_scheme[char])
-                hexline.append(' ')
+        for group in groupby(line, group_width):
+            group_length = len(group)
+            group = reversed(group) if flip_group_endianess else group
+            for idx, char in enumerate(group):
+                if flip_group_endianess and idx == group_length - 1:
+                    hexline.append(H.highlight_group_lsb(color_scheme[char]))
+                else:
+                    hexline.append(color_scheme[char])
+                hexline.append(f'{config_byte_separator}')
             hexline.append(' ')
 
         hexline.append(H.separator('%s' % config_separator))
-        for group in groupby(line, 4):
+        for group in groupby(line, group_width):
             for char in group:
                 hexline.append(printable[char])
             hexline.append(H.separator('%s' % config_separator))