Implement forensics signatures command and expand supported magic signatures dictionary

src/ctf/forensics.py

@@ -16,6 +16,24 @@ except ImportError:
     pwd = None
     grp = None
 
+COMMON_SIGNATURES = {
+    b"\x89PNG\r\n\x1a\n": ("PNG Image", [".png"]),
+    b"\xff\xd8\xff": ("JPEG Image", [".jpg", ".jpeg"]),
+    b"%PDF": ("PDF Document", [".pdf"]),
+    b"PK\x03\x04": ("ZIP Archive", [".zip"]),
+    b"\x7fELF": ("ELF Executable", [".elf"]),
+    b"MZ": ("PE Executable", [".exe", ".dll"]),
+    b"GIF87a": ("GIF Image", [".gif"]),
+    b"GIF89a": ("GIF Image", [".gif"]),
+    b"7z\xbc\xaf\x27\x1c": ("7-Zip Archive", [".7z"]),
+    b"\x1f\x8b": ("GZIP Archive", [".gz"]),
+    b"Rar!\x1a\x07\x00": ("RAR Archive", [".rar"]),
+    b"Rar!\x1a\x07\x01\x00": ("RAR Archive", [".rar"]),
+    b"BZh": ("BZIP2 Archive", [".bz2"]),
+    b"BM": ("BMP Image", [".bmp"]),
+    b"ID3": ("MP3 Audio", [".mp3"]),
+}
+
 @click.group(name="forensics")
 def forensics_group(): pass
 
@@ -65,7 +83,7 @@ def inspect(path):
     # Magic bytes
     try:
         with open(p, 'rb') as f:
-            magic = f.read(4).hex().upper()
+            magic = f.read(8).hex().upper()
     except Exception:
         magic = ""
         
@@ -100,11 +118,11 @@ def inspect(path):
     # Hard Links
     hard_links = stat_info.st_nlink
     
-    # Task 5: Inode & Device Identifiers
+    # Inode & Device Identifiers
     inode = stat_info.st_ino
     device = stat_info.st_dev
     
-    # Task 6: Extended Attributes
+    # Extended Attributes
     extended_attributes = {}
     if hasattr(os, "listxattr") and hasattr(os, "getxattr"):
         try:
@@ -163,3 +181,22 @@ def inspect(path):
         
     console.print(table)
     return meta
+
+@forensics_group.command(name="signatures")
+def list_signatures():
+    """List all supported file magic signatures and expected extensions."""
+    from rich.console import Console
+    from rich.table import Table
+
+    console = Console()
+    table = Table(title="Supported Magic Signatures", show_header=True)
+    table.add_column("Magic Bytes (Hex)", style="bold cyan")
+    table.add_column("File Type", style="bold green")
+    table.add_column("Expected Exts")
+
+    for signature, (type_name, exts) in COMMON_SIGNATURES.items():
+        hex_str = signature.hex().upper()
+        exts_str = ", ".join(exts) if exts else "Any / None"
+        table.add_row(hex_str, type_name, exts_str)
+
+    console.print(table)