JNI 静态注册与动态注册对 SO 符号暴露及保护的影响比较

#!/bin/bash
set -o pipefail
if [ $# -ne 1 ]; then
  echo "Usage: $0 <path/to/lib.so>" >&2
  exit 1
fi
SO="$1"
if [ ! -f "$SO" ]; then
  echo "Error: File '$SO' does not exist." >&2
  exit 1
fi
echo "=== Dynamic Symbols Analysis ==="
readelf -W --dyn-syms "$SO" || { echo "Failed to read dynamic symbols" >&2; exit 2; }
JAVA_COUNT=$(readelf -W --dyn-syms "$SO" | grep -c ' \bJava_' || true)
if readelf -W --dyn-syms "$SO" | grep -q ' \bJNI_OnLoad$'; then
  ONLOAD_FOUND=1
else
  ONLOAD_FOUND=0
fi
echo "Java_ symbols found: $JAVA_COUNT"
echo "JNI_OnLoad symbol: $( [ $ONLOAD_FOUND -eq 1 ] && echo 'YES' || echo 'NO' )"
if [ $JAVA_COUNT -gt 0 ]; then
  echo "Likely static registration (exports Java_ methods)"
elif [ $ONLOAD_FOUND -eq 1 ]; then
  echo "Only JNI_OnLoad found, might be dynamic registration"
else
  echo "No obvious JNI interface found"
fi
if readelf -W -r "$SO" | grep -q 'RegisterNatives'; then
  echo "Relocation to RegisterNatives present (dynamic registration hint)"
fi
exit 0