Detect image architecture from uname and fix 8.4.26 offset inventory

Author: devploit

docs/offset-inventory.md

@@ -13,7 +13,7 @@ a build still needs heap calibration before the chain can run.
 | php:8.3.0-apache | 8.3.0 | arm64 | 0x3771f0 | 0x467cf0 | c1b72099fc8c | offsets extracted; heap not calibrated |
 | php:8.3.35-apache | 8.3.35 | arm64 | 0x377428 | 0x46fcc0 | 1f2bc20742e6 | offsets extracted; heap not calibrated |
 | php:8.4.25-apache | 8.4.25 | arm64 | 0x42fa30 | 0x637ae0 | 2d2388a4b0af | offsets extracted; heap not calibrated |
-| php:8.4.26-apache | 8.4.26 | arm64 | 0x465370 | 0x65eb60 | 51663cf883b1 | offsets extracted; heap not calibrated |
+| php:8.4.26-apache | 8.4.26 | amd64 | 0x465370 | 0x65eb60 | 51663cf883b1 | offsets extracted; heap not calibrated |
 | php:8.5.0-apache | 8.5.0 | arm64 | 0x503510 | 0x731d80 | 5910f3f12fbd | offsets extracted; heap not calibrated |
 | php:8.5.10-apache | 8.5.10 | arm64 | 0x52e130 | 0x75d360 | 5f080d44d3f8 | offsets extracted; heap not calibrated |
 | php:8.5.11-apache | 8.5.11 | arm64 | 0x5314f0 | 0x761b80 | 64a617aeb392 | offsets extracted; heap not calibrated |

profiles/offsets/8.4.26-amd64.json

@@ -0,0 +1,13 @@
+{
+  "image": "php:8.4.26-apache",
+  "php_version": "8.4.26",
+  "branch": "8.4",
+  "arch": "amd64",
+  "libphp": {
+    "zif_system": "0x465370",
+    "zval_ptr_dtor": "0x65eb60",
+    "ps_globals": "0x1316820"
+  },
+  "libphp_sha256": "51663cf883b1223436d4c99f31dd0225735ea5573665e4242621eee7f4ee679c",
+  "status": "offsets extracted; heap not calibrated"
+}

tools/php2shell_offsets.py

@@ -125,6 +125,15 @@ def image_env(image: str) -> dict:
 
 
 def image_arch(image: str) -> str:
+    # Some imported/emulated images report an empty Architecture, so ask the
+    # image itself. uname inside the container is authoritative.
+    out = docker("run", "--rm", "--entrypoint", "uname", image, "-m", timeout=120)
+    machine = out.stdout.strip().lower()
+    if machine:
+        mapped = {"aarch64": "arm64", "arm64": "arm64",
+                  "x86_64": "amd64", "amd64": "amd64"}.get(machine)
+        if mapped:
+            return mapped
     out = docker("inspect", "--format", "{{.Architecture}}", image)
     arch = out.stdout.strip()
     if not arch or arch == "unknown":