Ghidra

Ghidra Headless Analysis Skill

Perform automated reverse engineering using Ghidra's analyzeHeadless tool. Import binaries, run analysis, decompile to C code, and extract useful information.

Quick Reference

Prerequisites

• Ghidra must be installed. On macOS: brew install --cask ghidra
• Java (OpenJDK 17+) must be available

The skill automatically locates Ghidra in common installation paths. Set GHIDRA_HOME environment variable if Ghidra is installed in a non-standard location.

Main Wrapper Script

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./scripts/ghidra-analyze.sh [options] <binary>

Wrapper that handles project creation/cleanup and provides a simpler interface to analyzeHeadless.

Options:

• -o, --output <dir> - Output directory for results (default: current dir)
• -s, --script <name> - Post-analysis script to run (can be repeated)
• -a, --script-args <args> - Arguments for the last specified script
• --script-path <path> - Additional script search path
• -p, --processor <id> - Processor/architecture (e.g., x86:LE:32:default)
• -c, --cspec <id> - Compiler spec (e.g., gcc, windows)
• --no-analysis - Skip auto-analysis (faster, but less info)
• --timeout <seconds> - Analysis timeout per file
• --keep-project - Keep the Ghidra project after analysis
• --project-dir <dir> - Directory for Ghidra project (default: /tmp)
• --project-name <name> - Project name (default: auto-generated)
• -v, --verbose - Verbose output

Built-in Export Scripts

ExportAll.java

Comprehensive export - runs all other exports and creates a summary. Best for initial analysis.

Output files:

• {name}_summary.txt - Overview: architecture, memory sections, function counts
• {name}_decompiled.c - All functions decompiled to C
• {name}_functions.json - Function list with signatures and calls
• {name}_strings.txt - All strings found
• {name}_interesting.txt - Functions matching security-relevant patterns

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./scripts/ghidra-analyze.sh -s ExportAll.java -o ./analysis firmware.bin

ExportDecompiled.java

Decompile all functions to C pseudocode.

Output: {name}_decompiled.c

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./scripts/ghidra-analyze.sh -s ExportDecompiled.java -o ./output program.exe

ExportFunctions.java

Export function list as JSON with addresses, signatures, parameters, and call relationships.

Output: {name}_functions.json

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{
  "program": "example.exe",
  "architecture": "x86",
  "functions": [
    {
      "name": "main",
      "address": "0x00401000",
      "size": 256,
      "signature": "int main(int argc, char **argv)",
      "returnType": "int",
      "callingConvention": "cdecl",
      "isExternal": false,
      "parameters": [{"name": "argc", "type": "int"}, ...],
      "calls": ["printf", "malloc", "process_data"],
      "calledBy": ["_start"]
    }
  ]
}

ExportStrings.java

Extract all strings (ASCII, Unicode) with addresses.

Output: {name}_strings.json

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./scripts/ghidra-analyze.sh -s ExportStrings.java -o ./output malware.exe

ExportCalls.java

Export function call graph showing caller/callee relationships.

Output: {name}_calls.json

Includes:

• Full call graph
• Potential entry points (functions with no callers)
• Most frequently called functions

ExportSymbols.java

Export all symbols: imports, exports, and internal symbols.

Output: {name}_symbols.json

Common Workflows

Analyze an Unknown Binary

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# Create output directory
mkdir -p ./analysis

# Run comprehensive analysis
./scripts/ghidra-analyze.sh -s ExportAll.java -o ./analysis unknown_binary

# Review the summary first
cat ./analysis/unknown_binary_summary.txt

# Look at interesting patterns (crypto, network, dangerous functions)
cat ./analysis/unknown_binary_interesting.txt

# Check specific decompiled functions
grep -A 50 "encrypt" ./analysis/unknown_binary_decompiled.c

Analyze Firmware

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# Specify ARM architecture for firmware
./scripts/ghidra-analyze.sh \
    -p "ARM:LE:32:v7" \
    -s ExportAll.java \
    -o ./firmware_analysis \
    firmware.bin

Quick Function Listing

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# Just get function names and addresses (faster)
./scripts/ghidra-analyze.sh --no-analysis -s ExportFunctions.java -o . program

# Parse with jq
cat program_functions.json | jq '.functions[] | "\(.address): \(.name)"'

Find Specific Patterns

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# After running ExportDecompiled, search for patterns
grep -n "password\|secret\|key" output_decompiled.c
grep -n "strcpy\|sprintf\|gets" output_decompiled.c

Analyze Multiple Binaries

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for bin in ./samples/*; do
    name=$(basename "$bin")
    ./scripts/ghidra-analyze.sh -s ExportAll.java -o "./results/$name" "$bin"
done

Architecture/Processor IDs

Common processor IDs for the -p option:

Find all available processors:

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ls "$(dirname $(./scripts/find-ghidra.sh))/../Ghidra/Processors/"

Troubleshooting

Ghidra Not Found

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# Check if Ghidra is installed
./scripts/find-ghidra.sh

# Set GHIDRA_HOME if in non-standard location
export GHIDRA_HOME=/path/to/ghidra_11.x_PUBLIC
./scripts/ghidra-analyze.sh ...

Analysis Takes Too Long

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# Set a timeout (seconds)
./scripts/ghidra-analyze.sh --timeout 300 -s ExportAll.java binary

# Skip analysis for quick export
./scripts/ghidra-analyze.sh --no-analysis -s ExportSymbols.java binary

Out of Memory

Edit the analyzeHeadless script or set:

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export MAXMEM=4G

Wrong Architecture Detected

Explicitly specify the processor:

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./scripts/ghidra-analyze.sh -p "ARM:LE:32:v7" -s ExportAll.java firmware.bin

Tips

1. Start with ExportAll.java - It gives you everything and the summary helps orient you
2. Check the interesting.txt file - It highlights security-relevant functions automatically
3. Use jq for JSON parsing - The JSON exports are designed to be machine-readable
4. Decompilation isn't perfect - Use it as a guide, cross-reference with disassembly
5. Large binaries take time - Use --timeout and consider --no-analysis for quick scans