# Termux su Wrapper Analysis

## Session Context
- Date: 2026-06-25
- Device: Android 16 (Termux)
- Issue: WeChat data extraction failed because Discovery Agent reported "No su program found"
- User correction: Device IS rooted with Magisk, but Termux's wrapper couldn't find su

## Key Finding: Termux's su is a Wrapper Script

Path: `/data/data/com.termux/files/usr/bin/su`

Content:
```sh
#!/data/data/com.termux/files/usr/bin/sh

unset LD_LIBRARY_PATH LD_PRELOAD

for p in /debug_ramdisk/su /sbin/su /system/sbin/su /system/bin/su /system/xbin/su /su/bin/su /magisk/.core/bin/su
do
	if [ -x $p ]; then
		# The su tool may require programs in PATH:
		PATH=/debug_ramdisk:/sbin:/sbin/su:/su/bin:/su/xbin:/system/bin:/system/xbin \
			exec $p "$@"
	fi
done

echo "No su program found on this device. Termux"
echo "does not supply tools for rooting, see e.g."
echo "http://www.androidcentral.com/root for"
echo "information about rooting Android."
exit 1
```

## Critical Insight

The wrapper searches these paths IN ORDER:
1. `/debug_ramdisk/su`
2. `/sbin/su`
3. `/system/sbin/su`
4. `/system/bin/su`
5. `/system/xbin/su`
6. `/su/bin/su`
7. `/magisk/.core/bin/su`

If Magisk's su is NOT in any of these paths, the wrapper fails even if root is active.

## What We Found on This Device

- Magisk app installed: `com.topjohnwu.magisk` ✓
- `/data/adb/` directory: does NOT exist
- `/data/adb/magisk/` directory: does NOT exist
- All standard su paths: EMPTY
- Termux wrapper: FAILS with "No su program found"

## Hypothesis

Magisk is installed but:
1. Zygisk is hiding su from Termux's namespace
2. OR su binary is in a non-standard path not checked by the wrapper
3. OR Magisk installation is incomplete (app installed but binaries not deployed)

## Resolution Path

1. Open Magisk app to check:
   - Is "Zygisk" enabled? (Disable it to expose su)
   - Is Termux in the denylist? (Remove it)
   - Does Superuser tab show any granted apps?

2. If Zygisk is required:
   - Add Termux to Magisk's allowlist
   - Or use a direct su path if known

3. If Magisk is broken:
   - Re-flash Magisk via recovery
   - Or use a different root method

## Lessons Learned

1. NEVER trust "No su program found" at face value
2. ALWAYS read the wrapper script to understand what paths are checked
3. Magisk app being installed ≠ su binary being accessible
4. Discovery agents that use `su -c "id"` will fail on Termux if wrapper can't find binary
5. User may be right about root being present — the issue is usually path/visibility