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# typed: false
# coding: utf-8
require 'openssl'
describe PDF::Reader::AesV3SecurityHandler do
let(:key) { "a" * 32 } # exactly 32 bytes for AES-256
let(:handler) { PDF::Reader::AesV3SecurityHandler.new(key) }
let(:reference) { PDF::Reader::Reference.new(1, 0) }
describe "#initialize" do
context "with valid 32-byte key" do
it "creates handler successfully" do
expect { PDF::Reader::AesV3SecurityHandler.new("a" * 32) }.not_to raise_error
end
end
context "with invalid key lengths" do
it "raises MalformedPDFError for short key" do
expect {
PDF::Reader::AesV3SecurityHandler.new("short")
}.to raise_error(
PDF::Reader::MalformedPDFError, "AES-256 key must be exactly 32 bytes, got 5"
)
end
it "raises MalformedPDFError for long key" do
expect {
PDF::Reader::AesV3SecurityHandler.new("a" * 40)
}.to raise_error(
PDF::Reader::MalformedPDFError, "AES-256 key must be exactly 32 bytes, got 40"
)
end
it "raises MalformedPDFError for empty key" do
expect {
PDF::Reader::AesV3SecurityHandler.new("")
}.to raise_error(
PDF::Reader::MalformedPDFError, "AES-256 key must be exactly 32 bytes, got 0"
)
end
end
end
describe "#decrypt" do
context "with ciphertext that is not a multiple of 16 bytes" do
it "raises MalformedPDFError" do
invalid_buf = "short"
expect {
handler.decrypt(invalid_buf, reference)
}.to raise_error(PDF::Reader::MalformedPDFError, "Ciphertext not a multiple of 16")
end
end
context "with exactly 16 bytes (IV only)" do
it "returns empty string" do
iv_only = "0123456789abcdef"
result = handler.decrypt(iv_only, reference)
expect(result).to eq("")
end
end
context "with valid padded ciphertext" do
it "decrypts successfully with PKCS#7 padding" do
plaintext = "Hello, World!"
buf = encrypt_test_data(plaintext, key, padding: true)
result = handler.decrypt(buf, reference)
expect(result).to eq(plaintext)
end
end
context "with ciphertext without padding and valid key" do
it "should decrypt successfully with no padding" do
plaintext = "1234567890123456" # exactly 16 bytes
buf = encrypt_test_data(plaintext, key, padding: false)
result = handler.decrypt(buf, reference)
expect(result).to eq(plaintext)
end
end
context "with ciphertext without padding and invalid key" do
it "returns incorrect data when key is wrong" do
wrong_key = "b" * 32 # different 32-byte key
wrong_handler = PDF::Reader::AesV3SecurityHandler.new(wrong_key)
plaintext = "1234567890123456"
buf = encrypt_test_data(plaintext, key, padding: false)
# Try to decrypt with wrong key - should return garbage, not raise error
result = wrong_handler.decrypt(buf, reference)
expect(result).not_to eq(plaintext)
expect(result).to be_a(String)
end
end
context "with padded ciphertext and invalid key" do
it "returns incorrect data when key is wrong" do
wrong_key = "b" * 32 # different 32-byte key
wrong_handler = PDF::Reader::AesV3SecurityHandler.new(wrong_key)
plaintext = "Hello, World!"
buf = encrypt_test_data(plaintext, key, padding: true)
# Try to decrypt with wrong key - should return garbage, not raise error
result = wrong_handler.decrypt(buf, reference)
expect(result).not_to eq(plaintext)
expect(result).to be_a(String)
end
end
context "with malformed ciphertext" do
it "returns a string with garbage content" do
# Create invalid ciphertext with proper 32-byte key handler
iv = "0123456789abcdef"
corrupted_data = "corrupted_data16" # exactly 16 bytes
buf = iv + corrupted_data
result = handler.decrypt(buf, reference)
expect(result).to be_a(String)
end
end
end
private
# Helper method to create encrypted test data for AES-V3
# @param plaintext [String] the text to encrypt
# @param encryption_key [String] the encryption key to use (32 bytes for AES-256)
# @param padding [Boolean] whether to use PKCS#7 padding
# @return [String] IV + ciphertext ready for decrypt method
def encrypt_test_data(plaintext, encryption_key, padding: true)
# AES-V3 uses the key directly without object reference modification
cipher = OpenSSL::Cipher.new("AES-256-CBC")
cipher.encrypt
cipher.padding = 0 unless padding
cipher.key = encryption_key.dup
iv = cipher.random_iv
ciphertext = cipher.update(plaintext) + cipher.final
# Return IV + ciphertext for the handler
iv + ciphertext
end
end
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