Test/ssrf ip overflow regression 3118

[Shan7Usmani]

Summary

Adds regression tests for the signed 32-bit integer overflow in ipToNumber that bypassed SSRF protection for 192.168.x.x and 172.16.x.x IP ranges. The overflow bug is already fixed (>>> 0 unsigned shift in ssrf-protection.ts), but had no test coverage for direct IP literal private ranges.

Closes #3118

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Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that changes existing behavior)
• 📝 Documentation update
• ♻️ Refactor / code cleanup (no functional change)
• ⚡ Performance improvement
• 🔒 Security fix
• 🧪 Tests only

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What Changed

• Added 4 test cases to test/ssrf-protection.test.ts covering direct IP literal private ranges:
  • 192.168.x.x (3 addresses)
  • 172.16.x.x (2 addresses)
  • 10.x.x.x (2 addresses)
  • 127.x.x.x (2 addresses)

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How to Test

1. Run npx vitest run test/ssrf-protection.test.ts
2. Verify all 23 tests pass (19 existing + 4 new)

Expected result: All tests pass, including the new regression tests confirming isSafeUrl returns false for private IP literals.

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Checklist

• Linked the related issue above
• Self-reviewed my own diff
• No unnecessary console.log, debug code, or commented-out blocks
• npm run lint passes locally
• No TypeScript errors (npm run type-check)
• Added or updated tests where applicable
• Updated documentation / comments if behavior changed

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Accessibility (UI changes only)

N/A — tests only.

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Additional Context

The SSRF fix (>>> 0 unsigned right shift in ipToNumber) was already merged by a prior contributor. These tests ensure the overflow regression cannot reappear silently.

[github-actions]

GSSoC Label Checklist 🏷️

@Priyanshu-byte-coder — please apply the appropriate labels before merging:

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