/*
* OpenSSL provides SSL, TLS and general purpose cryptography. It wraps the
* OpenSSL[http://www.openssl.org/] library.
*
* = Install
*
* OpenSSL comes bundled with the Standard Library of Ruby.
*
* This means the OpenSSL extension is compiled with Ruby and packaged on
* build. During compile time, Ruby will need to link against the OpenSSL
* library on your system. However, you cannot use openssl provided by Apple to
* build standard library openssl.
*
* If you use OSX, you should install another openssl and run ```./configure
* --with-openssl-dir=/path/to/another-openssl```. For Homebrew user, run `brew
* install openssl` and then ```./configure --with-openssl-dir=`brew --prefix
* openssl` ```.
*
* = Examples
*
* All examples assume you have loaded OpenSSL with:
*
* require 'openssl'
*
* These examples build atop each other. For example the key created in the
* next is used in throughout these examples.
*
* == Keys
*
* === Creating a Key
*
* This example creates a 2048 bit RSA keypair and writes it to the current
* directory.
*
* key = OpenSSL::PKey::RSA.new 2048
*
* open 'private_key.pem', 'w' do |io| io.write key.to_pem end
* open 'public_key.pem', 'w' do |io| io.write key.public_key.to_pem end
*
* === Exporting a Key
*
* Keys saved to disk without encryption are not secure as anyone who gets
* ahold of the key may use it unless it is encrypted. In order to securely
* export a key you may export it with a pass phrase.
*
* cipher = OpenSSL::Cipher.new 'AES-128-CBC'
* pass_phrase = 'my secure pass phrase goes here'
*
* key_secure = key.export cipher, pass_phrase
*
* open 'private.secure.pem', 'w' do |io|
* io.write key_secure
* end
*
* OpenSSL::Cipher.ciphers returns a list of available ciphers.
*
* === Loading a Key
*
* A key can also be loaded from a file.
*
* key2 = OpenSSL::PKey::RSA.new File.read 'private_key.pem'
* key2.public? # => true
*
* or
*
* key3 = OpenSSL::PKey::RSA.new File.read 'public_key.pem'
* key3.private? # => false
*
* === Loading an Encrypted Key
*
* OpenSSL will prompt you for your pass phrase when loading an encrypted key.
* If you will not be able to type in the pass phrase you may provide it when
* loading the key:
*
* key4_pem = File.read 'private.secure.pem'
* key4 = OpenSSL::PKey::RSA.new key4_pem, pass_phrase
*
* == RSA Encryption
*
* RSA provides encryption and decryption using the public and private keys.
* You can use a variety of padding methods depending upon the intended use of
* encrypted data.
*
* === Encryption & Decryption
*
* Asymmetric public/private key encryption is slow and victim to attack in
* cases where it is used without padding or directly to encrypt larger chunks
* of data. Typical use cases for RSA encryption involve "wrapping" a symmetric
* key with the public key of the recipient who would "unwrap" that symmetric
* key again using their private key.
* The following illustrates a simplified example of such a key transport
* scheme. It shouldn't be used in practice, though, standardized protocols
* should always be preferred.
*
* wrapped_key = key.public_encrypt key
*
* A symmetric key encrypted with the public key can only be decrypted with
* the corresponding private key of the recipient.
*
* original_key = key.private_decrypt wrapped_key
*
* By default PKCS#1 padding will be used, but it is also possible to use
* other forms of padding, see PKey::RSA for further details.
*
* === Signatures
*
* Using "private_encrypt" to encrypt some data with the private key is
* equivalent to applying a digital signature to the data. A verifying
* party may validate the signature by comparing the result of decrypting
* the signature with "public_decrypt" to the original data. However,
* OpenSSL::PKey already has methods "sign" and "verify" that handle
* digital signatures in a standardized way - "private_encrypt" and
* "public_decrypt" shouldn't be used in practice.
*
* To sign a document, a cryptographically secure hash of the document is
* computed first, which is then signed using the private key.
*
* digest = OpenSSL::Digest::SHA256.new
* signature = key.sign digest, document
*
* To validate the signature, again a hash of the document is computed and
* the signature is decrypted using the public key. The result is then
* compared to the hash just computed, if they are equal the signature was
* valid.
*
* digest = OpenSSL::Digest::SHA256.new
* if key.verify digest, signature, document
* puts 'Valid'
* else
* puts 'Invalid'
* end
*
* == PBKDF2 Password-based Encryption
*
* If supported by the underlying OpenSSL version used, Password-based
* Encryption should use the features of PKCS5. If not supported or if
* required by legacy applications, the older, less secure methods specified
* in RFC 2898 are also supported (see below).
*
* PKCS5 supports PBKDF2 as it was specified in PKCS#5
* v2.0[http://www.rsa.com/rsalabs/node.asp?id=2127]. It still uses a
* password, a salt, and additionally a number of iterations that will
* slow the key derivation process down. The slower this is, the more work
* it requires being able to brute-force the resulting key.
*
* === Encryption
*
* The strategy is to first instantiate a Cipher for encryption, and
* then to generate a random IV plus a key derived from the password
* using PBKDF2. PKCS #5 v2.0 recommends at least 8 bytes for the salt,
* the number of iterations largely depends on the hardware being used.
*
* cipher = OpenSSL::Cipher.new 'AES-128-CBC'
* cipher.encrypt
* iv = cipher.random_iv
*
* pwd = 'some hopefully not to easily guessable password'
* salt = OpenSSL::Random.random_bytes 16
* iter = 20000
* key_len = cipher.key_len
* digest = OpenSSL::Digest::SHA256.new
*
* key = OpenSSL::PKCS5.pbkdf2_hmac(pwd, salt, iter, key_len, digest)
* cipher.key = key
*
* Now encrypt the data:
*
* encrypted = cipher.update document
* encrypted << cipher.final
*
* === Decryption
*
* Use the same steps as before to derive the symmetric AES key, this time
* setting the Cipher up for decryption.
*
* cipher = OpenSSL::Cipher.new 'AES-128-CBC'
* cipher.decrypt
* cipher.iv = iv # the one generated with #random_iv
*
* pwd = 'some hopefully not to easily guessable password'
* salt = ... # the one generated above
* iter = 20000
* key_len = cipher.key_len
* digest = OpenSSL::Digest::SHA256.new
*
* key = OpenSSL::PKCS5.pbkdf2_hmac(pwd, salt, iter, key_len, digest)
* cipher.key = key
*
* Now decrypt the data:
*
* decrypted = cipher.update encrypted
* decrypted << cipher.final
*
* == PKCS #5 Password-based Encryption
*
* PKCS #5 is a password-based encryption standard documented at
* RFC2898[http://www.ietf.org/rfc/rfc2898.txt]. It allows a short password or
* passphrase to be used to create a secure encryption key. If possible, PBKDF2
* as described above should be used if the circumstances allow it.
*
* PKCS #5 uses a Cipher, a pass phrase and a salt to generate an encryption
* key.
*
* pass_phrase = 'my secure pass phrase goes here'
* salt = '8 octets'
*
* === Encryption
*
* First set up the cipher for encryption
*
* encryptor = OpenSSL::Cipher.new 'AES-128-CBC'
* encryptor.encrypt
* encryptor.pkcs5_keyivgen pass_phrase, salt
*
* Then pass the data you want to encrypt through
*
* encrypted = encryptor.update 'top secret document'
* encrypted << encryptor.final
*
* === Decryption
*
* Use a new Cipher instance set up for decryption
*
* decryptor = OpenSSL::Cipher.new 'AES-128-CBC'
* decryptor.decrypt
* decryptor.pkcs5_keyivgen pass_phrase, salt
*
* Then pass the data you want to decrypt through
*
* plain = decryptor.update encrypted
* plain << decryptor.final
*
* == X509 Certificates
*
* === Creating a Certificate
*
* This example creates a self-signed certificate using an RSA key and a SHA1
* signature.
*
* name = OpenSSL::X509::Name.parse 'CN=nobody/DC=example'
*
* cert = OpenSSL::X509::Certificate.new
* cert.version = 2
* cert.serial = 0
* cert.not_before = Time.now
* cert.not_after = Time.now + 3600
*
* cert.public_key = key.public_key
* cert.subject = name
*
* === Certificate Extensions
*
* You can add extensions to the certificate with
* OpenSSL::SSL::ExtensionFactory to indicate the purpose of the certificate.
*
* extension_factory = OpenSSL::X509::ExtensionFactory.new nil, cert
*
* cert.add_extension \
* extension_factory.create_extension('basicConstraints', 'CA:FALSE', true)
*
* cert.add_extension \
* extension_factory.create_extension(
* 'keyUsage', 'keyEncipherment,dataEncipherment,digitalSignature')
*
* cert.add_extension \
* extension_factory.create_extension('subjectKeyIdentifier', 'hash')
*
* The list of supported extensions (and in some cases their possible values)
* can be derived from the "objects.h" file in the OpenSSL source code.
*
* === Signing a Certificate
*
* To sign a certificate set the issuer and use OpenSSL::X509::Certificate#sign
* with a digest algorithm. This creates a self-signed cert because we're using
* the same name and key to sign the certificate as was used to create the
* certificate.
*
* cert.issuer = name
* cert.sign key, OpenSSL::Digest::SHA1.new
*
* open 'certificate.pem', 'w' do |io| io.write cert.to_pem end
*
* === Loading a Certificate
*
* Like a key, a cert can also be loaded from a file.
*
* cert2 = OpenSSL::X509::Certificate.new File.read 'certificate.pem'
*
* === Verifying a Certificate
*
* Certificate#verify will return true when a certificate was signed with the
* given public key.
*
* raise 'certificate can not be verified' unless cert2.verify key
*
* == Certificate Authority
*
* A certificate authority (CA) is a trusted third party that allows you to
* verify the ownership of unknown certificates. The CA issues key signatures
* that indicate it trusts the user of that key. A user encountering the key
* can verify the signature by using the CA's public key.
*
* === CA Key
*
* CA keys are valuable, so we encrypt and save it to disk and make sure it is
* not readable by other users.
*
* ca_key = OpenSSL::PKey::RSA.new 2048
*
* cipher = OpenSSL::Cipher::Cipher.new 'AES-128-CBC'
*
* open 'ca_key.pem', 'w', 0400 do |io|
* io.write ca_key.export(cipher, pass_phrase)
* end
*
* === CA Certificate
*
* A CA certificate is created the same way we created a certificate above, but
* with different extensions.
*
* ca_name = OpenSSL::X509::Name.parse 'CN=ca/DC=example'
*
* ca_cert = OpenSSL::X509::Certificate.new
* ca_cert.serial = 0
* ca_cert.version = 2
* ca_cert.not_before = Time.now
* ca_cert.not_after = Time.now + 86400
*
* ca_cert.public_key = ca_key.public_key
* ca_cert.subject = ca_name
* ca_cert.issuer = ca_name
*
* extension_factory = OpenSSL::X509::ExtensionFactory.new
* extension_factory.subject_certificate = ca_cert
* extension_factory.issuer_certificate = ca_cert
*
* ca_cert.add_extension \
* extension_factory.create_extension('subjectKeyIdentifier', 'hash')
*
* This extension indicates the CA's key may be used as a CA.
*
* ca_cert.add_extension \
* extension_factory.create_extension('basicConstraints', 'CA:TRUE', true)
*
* This extension indicates the CA's key may be used to verify signatures on
* both certificates and certificate revocations.
*
* ca_cert.add_extension \
* extension_factory.create_extension(
* 'keyUsage', 'cRLSign,keyCertSign', true)
*
* Root CA certificates are self-signed.
*
* ca_cert.sign ca_key, OpenSSL::Digest::SHA1.new
*
* The CA certificate is saved to disk so it may be distributed to all the
* users of the keys this CA will sign.
*
* open 'ca_cert.pem', 'w' do |io|
* io.write ca_cert.to_pem
* end
*
* === Certificate Signing Request
*
* The CA signs keys through a Certificate Signing Request (CSR). The CSR
* contains the information necessary to identify the key.
*
* csr = OpenSSL::X509::Request.new
* csr.version = 0
* csr.subject = name
* csr.public_key = key.public_key
* csr.sign key, OpenSSL::Digest::SHA1.new
*
* A CSR is saved to disk and sent to the CA for signing.
*
* open 'csr.pem', 'w' do |io|
* io.write csr.to_pem
* end
*
* === Creating a Certificate from a CSR
*
* Upon receiving a CSR the CA will verify it before signing it. A minimal
* verification would be to check the CSR's signature.
*
* csr = OpenSSL::X509::Request.new File.read 'csr.pem'
*
* raise 'CSR can not be verified' unless csr.verify csr.public_key
*
* After verification a certificate is created, marked for various usages,
* signed with the CA key and returned to the requester.
*
* csr_cert = OpenSSL::X509::Certificate.new
* csr_cert.serial = 0
* csr_cert.version = 2
* csr_cert.not_before = Time.now
* csr_cert.not_after = Time.now + 600
*
* csr_cert.subject = csr.subject
* csr_cert.public_key = csr.public_key
* csr_cert.issuer = ca_cert.subject
*
* extension_factory = OpenSSL::X509::ExtensionFactory.new
* extension_factory.subject_certificate = csr_cert
* extension_factory.issuer_certificate = ca_cert
*
* csr_cert.add_extension \
* extension_factory.create_extension('basicConstraints', 'CA:FALSE')
*
* csr_cert.add_extension \
* extension_factory.create_extension(
* 'keyUsage', 'keyEncipherment,dataEncipherment,digitalSignature')
*
* csr_cert.add_extension \
* extension_factory.create_extension('subjectKeyIdentifier', 'hash')
*
* csr_cert.sign ca_key, OpenSSL::Digest::SHA1.new
*
* open 'csr_cert.pem', 'w' do |io|
* io.write csr_cert.to_pem
* end
*
* == SSL and TLS Connections
*
* Using our created key and certificate we can create an SSL or TLS connection.
* An SSLContext is used to set up an SSL session.
*
* context = OpenSSL::SSL::SSLContext.new
*
* === SSL Server
*
* An SSL server requires the certificate and private key to communicate
* securely with its clients:
*
* context.cert = cert
* context.key = key
*
* Then create an SSLServer with a TCP server socket and the context. Use the
* SSLServer like an ordinary TCP server.
*
* require 'socket'
*
* tcp_server = TCPServer.new 5000
* ssl_server = OpenSSL::SSL::SSLServer.new tcp_server, context
*
* loop do
* ssl_connection = ssl_server.accept
*
* data = connection.gets
*
* response = "I got #{data.dump}"
* puts response
*
* connection.puts "I got #{data.dump}"
* connection.close
* end
*
* === SSL client
*
* An SSL client is created with a TCP socket and the context.
* SSLSocket#connect must be called to initiate the SSL handshake and start
* encryption. A key and certificate are not required for the client socket.
*
* require 'socket'
*
* tcp_client = TCPSocket.new 'localhost', 5000
* ssl_client = OpenSSL::SSL::SSLSocket.new client_socket, context
* ssl_client.connect
*
* ssl_client.puts "hello server!"
* puts ssl_client.gets
*
* === Peer Verification
*
* An unverified SSL connection does not provide much security. For enhanced
* security the client or server can verify the certificate of its peer.
*
* The client can be modified to verify the server's certificate against the
* certificate authority's certificate:
*
* context.ca_file = 'ca_cert.pem'
* context.verify_mode = OpenSSL::SSL::VERIFY_PEER
*
* require 'socket'
*
* tcp_client = TCPSocket.new 'localhost', 5000
* ssl_client = OpenSSL::SSL::SSLSocket.new client_socket, context
* ssl_client.connect
*
* ssl_client.puts "hello server!"
* puts ssl_client.gets
*
* If the server certificate is invalid or <tt>context.ca_file</tt> is not set
* when verifying peers an OpenSSL::SSL::SSLError will be raised.
*
*/
void
Init_openssl(void)
{
/*
* Init timezone info
*/
#if 0
tzset();
#endif
/*
* Init all digests, ciphers
*/
/* CRYPTO_malloc_init(); */
/* ENGINE_load_builtin_engines(); */
OpenSSL_add_ssl_algorithms();
OpenSSL_add_all_algorithms();
ERR_load_crypto_strings();
SSL_load_error_strings();
/*
* FIXME:
* On unload do:
*/
#if 0
CONF_modules_unload(1);
destroy_ui_method();
EVP_cleanup();
ENGINE_cleanup();
CRYPTO_cleanup_all_ex_data();
ERR_remove_state(0);
ERR_free_strings();
#endif
/*
* Init main module
*/
mOSSL = rb_define_module("OpenSSL");
rb_global_variable(&mOSSL);
/*
* OpenSSL ruby extension version
*/
rb_define_const(mOSSL, "VERSION", rb_str_new2(OSSL_VERSION));
/*
* Version of OpenSSL the ruby OpenSSL extension was built with
*/
rb_define_const(mOSSL, "OPENSSL_VERSION", rb_str_new2(OPENSSL_VERSION_TEXT));
/*
* Version of OpenSSL the ruby OpenSSL extension is running with
*/
rb_define_const(mOSSL, "OPENSSL_LIBRARY_VERSION", rb_str_new2(SSLeay_version(SSLEAY_VERSION)));
/*
* Version number of OpenSSL the ruby OpenSSL extension was built with
* (base 16)
*/
rb_define_const(mOSSL, "OPENSSL_VERSION_NUMBER", INT2NUM(OPENSSL_VERSION_NUMBER));
/*
* Boolean indicating whether OpenSSL is FIPS-enabled or not
*/
#ifdef HAVE_OPENSSL_FIPS
rb_define_const(mOSSL, "OPENSSL_FIPS", Qtrue);
#else
rb_define_const(mOSSL, "OPENSSL_FIPS", Qfalse);
#endif
rb_define_module_function(mOSSL, "fips_mode=", ossl_fips_mode_set, 1);
/*
* Generic error,
* common for all classes under OpenSSL module
*/
eOSSLError = rb_define_class_under(mOSSL,"OpenSSLError",rb_eStandardError);
rb_global_variable(&eOSSLError);
/*
* Verify callback Proc index for ext-data
*/
if ((ossl_verify_cb_idx = X509_STORE_CTX_get_ex_new_index(0, (void *)"ossl_verify_cb_idx", 0, 0, 0)) < 0)
ossl_raise(eOSSLError, "X509_STORE_CTX_get_ex_new_index");
/*
* Init debug core
*/
dOSSL = Qfalse;
rb_global_variable(&dOSSL);
rb_define_module_function(mOSSL, "debug", ossl_debug_get, 0);
rb_define_module_function(mOSSL, "debug=", ossl_debug_set, 1);
rb_define_module_function(mOSSL, "errors", ossl_get_errors, 0);
/*
* Get ID of to_der
*/
ossl_s_to_der = rb_intern("to_der");
Init_ossl_locks();
/*
* Init components
*/
Init_ossl_bn();
Init_ossl_cipher();
Init_ossl_config();
Init_ossl_digest();
Init_ossl_hmac();
Init_ossl_ns_spki();
Init_ossl_pkcs12();
Init_ossl_pkcs7();
Init_ossl_pkcs5();
Init_ossl_pkey();
Init_ossl_rand();
Init_ossl_ssl();
Init_ossl_x509();
Init_ossl_ocsp();
Init_ossl_engine();
Init_ossl_asn1();
}
/*
* OSSL library init
*/
void
Init_openssl()
{
/*
* Init timezone info
*/
#if 0
tzset();
#endif
/*
* Init all digests, ciphers
*/
/* CRYPTO_malloc_init(); */
/* ENGINE_load_builtin_engines(); */
OpenSSL_add_ssl_algorithms();
OpenSSL_add_all_algorithms();
ERR_load_crypto_strings();
SSL_load_error_strings();
/*
* FIXME:
* On unload do:
*/
#if 0
CONF_modules_unload(1);
destroy_ui_method();
EVP_cleanup();
ENGINE_cleanup();
CRYPTO_cleanup_all_ex_data();
ERR_remove_state(0);
ERR_free_strings();
#endif
/*
* Init main module
*/
mOSSL = rb_define_module("OpenSSL");
/*
* Constants
*/
rb_define_const(mOSSL, "VERSION", rb_str_new2(OSSL_VERSION));
rb_define_const(mOSSL, "OPENSSL_VERSION", rb_str_new2(OPENSSL_VERSION_TEXT));
rb_define_const(mOSSL, "OPENSSL_VERSION_NUMBER", INT2NUM(OPENSSL_VERSION_NUMBER));
/*
* Generic error,
* common for all classes under OpenSSL module
*/
eOSSLError = rb_define_class_under(mOSSL,"OpenSSLError",rb_eStandardError);
/*
* Verify callback Proc index for ext-data
*/
if ((ossl_verify_cb_idx = X509_STORE_CTX_get_ex_new_index(0, "ossl_verify_cb_idx", 0, 0, 0)) < 0)
ossl_raise(eOSSLError, "X509_STORE_CTX_get_ex_new_index");
/*
* Init debug core
*/
dOSSL = Qfalse;
rb_define_module_function(mOSSL, "debug", ossl_debug_get, 0);
rb_define_module_function(mOSSL, "debug=", ossl_debug_set, 1);
rb_define_module_function(mOSSL, "errors", ossl_get_errors, 0);
/*
* Get ID of to_der
*/
ossl_s_to_der = rb_intern("to_der");
/*
* Init components
*/
Init_ossl_bn();
Init_ossl_cipher();
Init_ossl_config();
Init_ossl_digest();
Init_ossl_hmac();
Init_ossl_ns_spki();
Init_ossl_pkcs12();
Init_ossl_pkcs7();
Init_ossl_pkcs5();
Init_ossl_pkey();
Init_ossl_rand();
Init_ossl_ssl();
Init_ossl_x509();
Init_ossl_ocsp();
Init_ossl_engine();
Init_ossl_asn1();
}