From 3bb8e37a8b33ca1dd860723ec4b70a16a8133ce4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?K=C5=8Dan?= Date: Sat, 14 Mar 2026 02:52:02 -0600 Subject: [PATCH 1/3] test: add error-path and edge-case test coverage Add t/error.t with 34 tests covering previously untested error paths: - Malformed PEM key loading (garbage, empty, undef, corrupted body) - Unrecognized public key format detection - Wrong/missing passphrase on encrypted keys - Public key operation restrictions (sign, decrypt, private_encrypt, check_key) - Corrupted/truncated/wrong-length ciphertext handling - Plaintext size boundary for OAEP padding (max and overflow) - Cross-key signature verification (sign with key1, verify with key2) - Empty message signing and verification - Truncated and extended signature rejection - Custom exponent key generation (3, 17, even exponent rejection) Co-Authored-By: Claude Opus 4.6 --- t/error.t | 155 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 155 insertions(+) create mode 100644 t/error.t diff --git a/t/error.t b/t/error.t new file mode 100644 index 0000000..4c2ebed --- /dev/null +++ b/t/error.t @@ -0,0 +1,155 @@ +use strict; +use Test::More; + +use Crypt::OpenSSL::Random; +use Crypt::OpenSSL::RSA; + +Crypt::OpenSSL::Random::random_seed("OpenSSL needs at least 32 bytes."); +Crypt::OpenSSL::RSA->import_random_seed(); + +my $rsa = Crypt::OpenSSL::RSA->generate_key(2048); +my $rsa_pub = Crypt::OpenSSL::RSA->new_public_key($rsa->get_public_key_string()); + +# --- Malformed key loading --- + +eval { Crypt::OpenSSL::RSA->new_private_key("not a key at all") }; +ok($@, "new_private_key croaks on garbage input"); + +eval { Crypt::OpenSSL::RSA->new_private_key("") }; +ok($@, "new_private_key croaks on empty string"); + +eval { Crypt::OpenSSL::RSA->new_private_key(undef) }; +ok($@, "new_private_key croaks on undef"); + +eval { + Crypt::OpenSSL::RSA->new_private_key( + "-----BEGIN RSA PRIVATE KEY-----\ngarbage\n-----END RSA PRIVATE KEY-----\n" + ); +}; +ok($@, "new_private_key croaks on corrupted PEM body"); + +eval { Crypt::OpenSSL::RSA->_new_public_key_pkcs1("not a key") }; +ok($@, "_new_public_key_pkcs1 croaks on garbage input"); + +eval { Crypt::OpenSSL::RSA->_new_public_key_x509("not a key") }; +ok($@, "_new_public_key_x509 croaks on garbage input"); + +# --- Unrecognized public key format (Perl-level croak) --- + +eval { Crypt::OpenSSL::RSA->new_public_key("-----BEGIN CERTIFICATE-----\nfoo\n-----END CERTIFICATE-----\n") }; +like($@, qr/unrecognized key format/, "new_public_key croaks on unrecognized PEM header"); + +eval { Crypt::OpenSSL::RSA->new_public_key("just plain text") }; +like($@, qr/unrecognized key format/, "new_public_key croaks on plain text"); + +# --- Wrong passphrase on encrypted key --- + +my $encrypted_pem = $rsa->get_private_key_string("correct_passphrase", "aes-128-cbc"); +eval { Crypt::OpenSSL::RSA->new_private_key($encrypted_pem, "wrong_passphrase") }; +ok($@, "new_private_key croaks on wrong passphrase"); + +eval { Crypt::OpenSSL::RSA->new_private_key($encrypted_pem) }; +ok($@, "new_private_key croaks on encrypted key without passphrase"); + +# --- Public key cannot perform private operations --- + +eval { $rsa_pub->sign("hello") }; +like($@, qr/Public keys cannot sign/i, "public key cannot sign"); + +eval { $rsa_pub->decrypt("hello") }; +like($@, qr/Public keys cannot decrypt/i, "public key cannot decrypt"); + +eval { $rsa_pub->private_encrypt("hello") }; +like($@, qr/Public keys cannot private_encrypt/i, "public key cannot private_encrypt"); + +eval { $rsa_pub->check_key() }; +like($@, qr/Public keys cannot be checked/i, "public key cannot check_key"); + +# --- Corrupted ciphertext --- + +$rsa->use_pkcs1_oaep_padding(); +my $ciphertext = $rsa->encrypt("test message"); + +# Flip bits in ciphertext +my $corrupted = $ciphertext; +substr($corrupted, 10, 1) ^= "\xff"; +eval { $rsa->decrypt($corrupted) }; +ok($@, "decrypt croaks on corrupted ciphertext"); + +# Wrong-length ciphertext +eval { $rsa->decrypt("too short") }; +ok($@, "decrypt croaks on wrong-length ciphertext"); + +eval { $rsa->decrypt("") }; +ok($@, "decrypt croaks on empty ciphertext"); + +# --- Plaintext too large for padding mode --- + +$rsa->use_pkcs1_oaep_padding(); +my $max_oaep = $rsa->size() - 42; +my $too_large = "x" x ($max_oaep + 1); +eval { $rsa->encrypt($too_large) }; +ok($@, "encrypt croaks when plaintext exceeds OAEP max size"); + +# Exact max should work +my $exact_max = "x" x $max_oaep; +my $ct = eval { $rsa->encrypt($exact_max) }; +ok(!$@, "encrypt succeeds at exact OAEP max size"); +is(eval { $rsa->decrypt($ct) }, $exact_max, "round-trip at OAEP max size"); + +# --- Cross-key signature verification --- + +my $rsa2 = Crypt::OpenSSL::RSA->generate_key(2048); +$rsa->use_pkcs1_pss_padding(); +$rsa2->use_pkcs1_pss_padding(); + +my $sig = $rsa->sign("message to sign"); +ok(!$rsa2->verify("message to sign", $sig), "signature from key1 does not verify with key2"); + +my $rsa2_pub = Crypt::OpenSSL::RSA->new_public_key($rsa2->get_public_key_string()); +$rsa2_pub->use_pkcs1_pss_padding(); +ok(!$rsa2_pub->verify("message to sign", $sig), "signature from key1 does not verify with key2 public"); + +# --- Empty message signing --- + +my $empty_sig = eval { $rsa->sign("") }; +ok(!$@, "sign succeeds on empty message"); +ok($rsa->verify("", $empty_sig), "verify succeeds on empty message signature"); +ok(!$rsa->verify("not empty", $empty_sig), "empty message signature does not verify different message"); + +# --- Truncated signature --- + +my $full_sig = $rsa->sign("test data"); +my $truncated_sig = substr($full_sig, 0, length($full_sig) - 1); +ok(!eval { $rsa->verify("test data", $truncated_sig) }, "truncated signature does not verify"); + +my $extended_sig = $full_sig . "\x00"; +ok(!eval { $rsa->verify("test data", $extended_sig) }, "extended signature does not verify"); + +# --- Key size boundary --- + +my $small_rsa = eval { Crypt::OpenSSL::RSA->generate_key(512) }; +ok(!$@, "512-bit key generation succeeds"); +is($small_rsa->size() * 8, 512, "512-bit key has correct size"); + +# --- generate_key with custom exponent --- + +my $rsa_e3 = eval { Crypt::OpenSSL::RSA->generate_key(2048, 3) }; +SKIP: { + skip "OpenSSL rejected exponent 3", 2 if $@; + ok($rsa_e3, "generate_key with exponent 3 succeeds"); + ok($rsa_e3->check_key(), "key with exponent 3 passes check_key"); +} + +my $rsa_e17 = eval { Crypt::OpenSSL::RSA->generate_key(2048, 17) }; +SKIP: { + skip "OpenSSL rejected exponent 17", 2 if $@; + ok($rsa_e17, "generate_key with exponent 17 succeeds"); + ok($rsa_e17->check_key(), "key with exponent 17 passes check_key"); +} + +# Even exponent should fail +eval { Crypt::OpenSSL::RSA->generate_key(2048, 2) }; +ok($@, "generate_key croaks on even exponent"); + +done_testing; From b40c4705f7304fa34b7851489c1fd3d64eaff55e Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?K=C5=8Dan?= Date: Mon, 16 Mar 2026 19:48:49 -0600 Subject: [PATCH 2/3] rebase: apply review feedback on #95 --- t/error.t | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/t/error.t b/t/error.t index 4c2ebed..8493729 100644 --- a/t/error.t +++ b/t/error.t @@ -48,8 +48,8 @@ my $encrypted_pem = $rsa->get_private_key_string("correct_passphrase", "aes-128- eval { Crypt::OpenSSL::RSA->new_private_key($encrypted_pem, "wrong_passphrase") }; ok($@, "new_private_key croaks on wrong passphrase"); -eval { Crypt::OpenSSL::RSA->new_private_key($encrypted_pem) }; -ok($@, "new_private_key croaks on encrypted key without passphrase"); +eval { Crypt::OpenSSL::RSA->new_private_key($encrypted_pem, "") }; +ok($@, "new_private_key croaks on encrypted key with empty passphrase"); # --- Public key cannot perform private operations --- @@ -104,11 +104,11 @@ $rsa->use_pkcs1_pss_padding(); $rsa2->use_pkcs1_pss_padding(); my $sig = $rsa->sign("message to sign"); -ok(!$rsa2->verify("message to sign", $sig), "signature from key1 does not verify with key2"); +ok(!eval { $rsa2->verify("message to sign", $sig) }, "signature from key1 does not verify with key2"); my $rsa2_pub = Crypt::OpenSSL::RSA->new_public_key($rsa2->get_public_key_string()); $rsa2_pub->use_pkcs1_pss_padding(); -ok(!$rsa2_pub->verify("message to sign", $sig), "signature from key1 does not verify with key2 public"); +ok(!eval { $rsa2_pub->verify("message to sign", $sig) }, "signature from key1 does not verify with key2 public"); # --- Empty message signing --- @@ -129,8 +129,11 @@ ok(!eval { $rsa->verify("test data", $extended_sig) }, "extended signature does # --- Key size boundary --- my $small_rsa = eval { Crypt::OpenSSL::RSA->generate_key(512) }; -ok(!$@, "512-bit key generation succeeds"); -is($small_rsa->size() * 8, 512, "512-bit key has correct size"); +SKIP: { + skip "OpenSSL 3.x rejects 512-bit keys at default security level", 2 if $@; + ok($small_rsa, "512-bit key generation succeeds"); + is($small_rsa->size() * 8, 512, "512-bit key has correct size"); +} # --- generate_key with custom exponent --- From 1474085dce9d564b77a1afce2411961e011c1e04 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?K=C5=8Dan?= Date: Wed, 18 Mar 2026 02:22:23 -0600 Subject: [PATCH 3/3] rebase: apply review feedback on #95 --- t/error.t | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/t/error.t b/t/error.t index 8493729..2e1e33a 100644 --- a/t/error.t +++ b/t/error.t @@ -48,8 +48,8 @@ my $encrypted_pem = $rsa->get_private_key_string("correct_passphrase", "aes-128- eval { Crypt::OpenSSL::RSA->new_private_key($encrypted_pem, "wrong_passphrase") }; ok($@, "new_private_key croaks on wrong passphrase"); -eval { Crypt::OpenSSL::RSA->new_private_key($encrypted_pem, "") }; -ok($@, "new_private_key croaks on encrypted key with empty passphrase"); +# Note: testing with no passphrase or empty passphrase is intentionally +# omitted — OpenSSL may prompt on the terminal, hanging non-interactive runs. # --- Public key cannot perform private operations ---