a6ab35a959
- Add HMAC-SHA256 checksum generation and validation (shareChecksum.ts) - Add PDF magic bytes validation to prevent file spoofing (pdfValidator.ts) - Add IP-based rate limiting for upload abuse prevention (uploadRateLimiter.ts) - Update BillingLocation interface with shareTTL and shareFirstVisitedAt fields - Add environment variables for share link security and TTL configuration 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
47 lines
1.6 KiB
TypeScript
47 lines
1.6 KiB
TypeScript
/**
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* Validate that uploaded file is a legitimate PDF
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* Checks magic bytes, not just MIME type
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*/
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export async function validatePdfFile(file: File): Promise<{ valid: boolean; error?: string }> {
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// Check file size first (quick rejection)
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const maxFileSizeKB = parseInt(process.env.MAX_PROOF_OF_PAYMENT_UPLOAD_SIZE_KB || '1024', 10);
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const maxFileSizeBytes = maxFileSizeKB * 1024;
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if (file.size === 0) {
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return { valid: false, error: 'File is empty' };
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}
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if (file.size > maxFileSizeBytes) {
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return { valid: false, error: `File size exceeds ${maxFileSizeKB} KB limit` };
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}
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// Read file content
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const arrayBuffer = await file.arrayBuffer();
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const buffer = Buffer.from(arrayBuffer);
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// Check PDF magic bytes (header signature)
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// PDF files must start with "%PDF-" (bytes: 25 50 44 46 2D)
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const header = buffer.toString('utf-8', 0, 5);
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if (!header.startsWith('%PDF-')) {
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return { valid: false, error: 'Invalid PDF file format' };
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}
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// Optional: Check for PDF version (1.0 to 2.0)
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const version = buffer.toString('utf-8', 5, 8); // e.g., "1.4", "1.7", "2.0"
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const versionMatch = version.match(/^(\d+\.\d+)/);
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if (!versionMatch) {
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return { valid: false, error: 'Invalid PDF version' };
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}
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// Optional: Verify PDF EOF marker (should end with %%EOF)
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// Note: Some PDFs have trailing data, so this is lenient
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const endSection = buffer.toString('utf-8', Math.max(0, buffer.length - 1024));
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if (!endSection.includes('%%EOF')) {
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console.warn('PDF missing EOF marker - may be corrupted');
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// Don't reject, just warn (some valid PDFs have non-standard endings)
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}
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return { valid: true };
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}
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