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-rw-r--r--ruby_1_9_3/ext/openssl/ossl_cipher.c754
1 files changed, 0 insertions, 754 deletions
diff --git a/ruby_1_9_3/ext/openssl/ossl_cipher.c b/ruby_1_9_3/ext/openssl/ossl_cipher.c
deleted file mode 100644
index 26851515cd..0000000000
--- a/ruby_1_9_3/ext/openssl/ossl_cipher.c
+++ /dev/null
@@ -1,754 +0,0 @@
-/*
- * $Id$
- * 'OpenSSL for Ruby' project
- * Copyright (C) 2001-2002 Michal Rokos <m.rokos@sh.cvut.cz>
- * All rights reserved.
- */
-/*
- * This program is licenced under the same licence as Ruby.
- * (See the file 'LICENCE'.)
- */
-#include "ossl.h"
-
-#define WrapCipher(obj, klass, ctx) \
- (obj) = Data_Wrap_Struct((klass), 0, ossl_cipher_free, (ctx))
-#define MakeCipher(obj, klass, ctx) \
- (obj) = Data_Make_Struct((klass), EVP_CIPHER_CTX, 0, ossl_cipher_free, (ctx))
-#define AllocCipher(obj, ctx) \
- memset(DATA_PTR(obj) = (ctx) = ALLOC(EVP_CIPHER_CTX), 0, sizeof(EVP_CIPHER_CTX))
-#define GetCipherInit(obj, ctx) do { \
- Data_Get_Struct((obj), EVP_CIPHER_CTX, (ctx)); \
-} while (0)
-#define GetCipher(obj, ctx) do { \
- GetCipherInit((obj), (ctx)); \
- if (!(ctx)) { \
- ossl_raise(rb_eRuntimeError, "Cipher not inititalized!"); \
- } \
-} while (0)
-#define SafeGetCipher(obj, ctx) do { \
- OSSL_Check_Kind((obj), cCipher); \
- GetCipher((obj), (ctx)); \
-} while (0)
-
-/*
- * Classes
- */
-VALUE cCipher;
-VALUE eCipherError;
-
-static VALUE ossl_cipher_alloc(VALUE klass);
-
-/*
- * PUBLIC
- */
-const EVP_CIPHER *
-GetCipherPtr(VALUE obj)
-{
- EVP_CIPHER_CTX *ctx;
-
- SafeGetCipher(obj, ctx);
-
- return EVP_CIPHER_CTX_cipher(ctx);
-}
-
-VALUE
-ossl_cipher_new(const EVP_CIPHER *cipher)
-{
- VALUE ret;
- EVP_CIPHER_CTX *ctx;
-
- ret = ossl_cipher_alloc(cCipher);
- AllocCipher(ret, ctx);
- EVP_CIPHER_CTX_init(ctx);
- if (EVP_CipherInit_ex(ctx, cipher, NULL, NULL, NULL, -1) != 1)
- ossl_raise(eCipherError, NULL);
-
- return ret;
-}
-
-/*
- * PRIVATE
- */
-static void
-ossl_cipher_free(EVP_CIPHER_CTX *ctx)
-{
- if (ctx) {
- EVP_CIPHER_CTX_cleanup(ctx);
- ruby_xfree(ctx);
- }
-}
-
-static VALUE
-ossl_cipher_alloc(VALUE klass)
-{
- VALUE obj;
-
- WrapCipher(obj, klass, 0);
-
- return obj;
-}
-
-/*
- * call-seq:
- * Cipher.new(string) -> cipher
- *
- * The string must contain a valid cipher name like "AES-128-CBC" or "3DES".
- *
- * A list of cipher names is available by calling OpenSSL::Cipher.ciphers.
- */
-static VALUE
-ossl_cipher_initialize(VALUE self, VALUE str)
-{
- EVP_CIPHER_CTX *ctx;
- const EVP_CIPHER *cipher;
- char *name;
- unsigned char key[EVP_MAX_KEY_LENGTH];
-
- name = StringValuePtr(str);
- GetCipherInit(self, ctx);
- if (ctx) {
- ossl_raise(rb_eRuntimeError, "Cipher already inititalized!");
- }
- AllocCipher(self, ctx);
- EVP_CIPHER_CTX_init(ctx);
- if (!(cipher = EVP_get_cipherbyname(name))) {
- ossl_raise(rb_eRuntimeError, "unsupported cipher algorithm (%s)", name);
- }
- /*
- * The EVP which has EVP_CIPH_RAND_KEY flag (such as DES3) allows
- * uninitialized key, but other EVPs (such as AES) does not allow it.
- * Calling EVP_CipherUpdate() without initializing key causes SEGV so we
- * set the data filled with "\0" as the key by default.
- */
- memset(key, 0, EVP_MAX_KEY_LENGTH);
- if (EVP_CipherInit_ex(ctx, cipher, NULL, key, NULL, -1) != 1)
- ossl_raise(eCipherError, NULL);
-
- return self;
-}
-
-static VALUE
-ossl_cipher_copy(VALUE self, VALUE other)
-{
- EVP_CIPHER_CTX *ctx1, *ctx2;
-
- rb_check_frozen(self);
- if (self == other) return self;
-
- GetCipherInit(self, ctx1);
- if (!ctx1) {
- AllocCipher(self, ctx1);
- }
- SafeGetCipher(other, ctx2);
- if (EVP_CIPHER_CTX_copy(ctx1, ctx2) != 1)
- ossl_raise(eCipherError, NULL);
-
- return self;
-}
-
-#ifdef HAVE_OBJ_NAME_DO_ALL_SORTED
-static void*
-add_cipher_name_to_ary(const OBJ_NAME *name, VALUE ary)
-{
- rb_ary_push(ary, rb_str_new2(name->name));
- return NULL;
-}
-#endif
-
-#ifdef HAVE_OBJ_NAME_DO_ALL_SORTED
-/*
- * call-seq:
- * Cipher.ciphers -> array[string...]
- *
- * Returns the names of all available ciphers in an array.
- */
-static VALUE
-ossl_s_ciphers(VALUE self)
-{
- VALUE ary;
-
- ary = rb_ary_new();
- OBJ_NAME_do_all_sorted(OBJ_NAME_TYPE_CIPHER_METH,
- (void(*)(const OBJ_NAME*,void*))add_cipher_name_to_ary,
- (void*)ary);
-
- return ary;
-}
-#else
-#define ossl_s_ciphers rb_f_notimplement
-#endif
-
-/*
- * call-seq:
- * cipher.reset -> self
- *
- * Fully resets the internal state of the Cipher. By using this, the same
- * Cipher instance may be used several times for en- or decryption tasks.
- *
- * Internally calls EVP_CipherInit_ex(ctx, NULL, NULL, NULL, NULL, -1).
- */
-static VALUE
-ossl_cipher_reset(VALUE self)
-{
- EVP_CIPHER_CTX *ctx;
-
- GetCipher(self, ctx);
- if (EVP_CipherInit_ex(ctx, NULL, NULL, NULL, NULL, -1) != 1)
- ossl_raise(eCipherError, NULL);
-
- return self;
-}
-
-static VALUE
-ossl_cipher_init(int argc, VALUE *argv, VALUE self, int mode)
-{
- EVP_CIPHER_CTX *ctx;
- unsigned char key[EVP_MAX_KEY_LENGTH], *p_key = NULL;
- unsigned char iv[EVP_MAX_IV_LENGTH], *p_iv = NULL;
- VALUE pass, init_v;
-
- if(rb_scan_args(argc, argv, "02", &pass, &init_v) > 0){
- /*
- * oops. this code mistakes salt for IV.
- * We deprecated the arguments for this method, but we decided
- * keeping this behaviour for backward compatibility.
- */
- const char *cname = rb_class2name(rb_obj_class(self));
- rb_warn("arguments for %s#encrypt and %s#decrypt were deprecated; "
- "use %s#pkcs5_keyivgen to derive key and IV",
- cname, cname, cname);
- StringValue(pass);
- GetCipher(self, ctx);
- if (NIL_P(init_v)) memcpy(iv, "OpenSSL for Ruby rulez!", sizeof(iv));
- else{
- StringValue(init_v);
- if (EVP_MAX_IV_LENGTH > RSTRING_LEN(init_v)) {
- memset(iv, 0, EVP_MAX_IV_LENGTH);
- memcpy(iv, RSTRING_PTR(init_v), RSTRING_LEN(init_v));
- }
- else memcpy(iv, RSTRING_PTR(init_v), sizeof(iv));
- }
- EVP_BytesToKey(EVP_CIPHER_CTX_cipher(ctx), EVP_md5(), iv,
- (unsigned char *)RSTRING_PTR(pass), RSTRING_LENINT(pass), 1, key, NULL);
- p_key = key;
- p_iv = iv;
- }
- else {
- GetCipher(self, ctx);
- }
- if (EVP_CipherInit_ex(ctx, NULL, NULL, p_key, p_iv, mode) != 1) {
- ossl_raise(eCipherError, NULL);
- }
-
- return self;
-}
-
-/*
- * call-seq:
- * cipher.encrypt -> self
- *
- * Initializes the Cipher for encryption.
- *
- * Make sure to call Cipher#encrypt or Cipher#decrypt before using any of the
- * following methods:
- * * [key=, iv=, random_key, random_iv, pkcs5_keyivgen]
- *
- * Internally calls EVP_CipherInit_ex(ctx, NULL, NULL, NULL, NULL, 1).
- */
-static VALUE
-ossl_cipher_encrypt(int argc, VALUE *argv, VALUE self)
-{
- return ossl_cipher_init(argc, argv, self, 1);
-}
-
-/*
- * call-seq:
- * cipher.decrypt -> self
- *
- * Initializes the Cipher for decryption.
- *
- * Make sure to call Cipher#encrypt or Cipher#decrypt before using any of the
- * following methods:
- * * [key=, iv=, random_key, random_iv, pkcs5_keyivgen]
- *
- * Internally calls EVP_CipherInit_ex(ctx, NULL, NULL, NULL, NULL, 0).
- */
-static VALUE
-ossl_cipher_decrypt(int argc, VALUE *argv, VALUE self)
-{
- return ossl_cipher_init(argc, argv, self, 0);
-}
-
-/*
- * call-seq:
- * cipher.pkcs5_keyivgen(pass [, salt [, iterations [, digest]]] ) -> nil
- *
- * Generates and sets the key/IV based on a password.
- *
- * WARNING: This method is only PKCS5 v1.5 compliant when using RC2, RC4-40,
- * or DES with MD5 or SHA1. Using anything else (like AES) will generate the
- * key/iv using an OpenSSL specific method. This method is deprecated and
- * should no longer be used. Use a PKCS5 v2 key generation method from
- * OpenSSL::PKCS5 instead.
- *
- * === Parameters
- * +salt+ must be an 8 byte string if provided.
- * +iterations+ is a integer with a default of 2048.
- * +digest+ is a Digest object that defaults to 'MD5'
- *
- * A minimum of 1000 iterations is recommended.
- *
- */
-static VALUE
-ossl_cipher_pkcs5_keyivgen(int argc, VALUE *argv, VALUE self)
-{
- EVP_CIPHER_CTX *ctx;
- const EVP_MD *digest;
- VALUE vpass, vsalt, viter, vdigest;
- unsigned char key[EVP_MAX_KEY_LENGTH], iv[EVP_MAX_IV_LENGTH], *salt = NULL;
- int iter;
-
- rb_scan_args(argc, argv, "13", &vpass, &vsalt, &viter, &vdigest);
- StringValue(vpass);
- if(!NIL_P(vsalt)){
- StringValue(vsalt);
- if(RSTRING_LEN(vsalt) != PKCS5_SALT_LEN)
- ossl_raise(eCipherError, "salt must be an 8-octet string");
- salt = (unsigned char *)RSTRING_PTR(vsalt);
- }
- iter = NIL_P(viter) ? 2048 : NUM2INT(viter);
- digest = NIL_P(vdigest) ? EVP_md5() : GetDigestPtr(vdigest);
- GetCipher(self, ctx);
- EVP_BytesToKey(EVP_CIPHER_CTX_cipher(ctx), digest, salt,
- (unsigned char *)RSTRING_PTR(vpass), RSTRING_LENINT(vpass), iter, key, iv);
- if (EVP_CipherInit_ex(ctx, NULL, NULL, key, iv, -1) != 1)
- ossl_raise(eCipherError, NULL);
- OPENSSL_cleanse(key, sizeof key);
- OPENSSL_cleanse(iv, sizeof iv);
-
- return Qnil;
-}
-
-
-/*
- * call-seq:
- * cipher.update(data [, buffer]) -> string or buffer
- *
- * Encrypts data in a streaming fashion. Hand consecutive blocks of data
- * to the +update+ method in order to encrypt it. Returns the encrypted
- * data chunk. When done, the output of Cipher#final should be additionally
- * added to the result.
- *
- * === Parameters
- * +data+ is a nonempty string.
- * +buffer+ is an optional string to store the result.
- */
-static VALUE
-ossl_cipher_update(int argc, VALUE *argv, VALUE self)
-{
- EVP_CIPHER_CTX *ctx;
- unsigned char *in;
- int in_len, out_len;
- VALUE data, str;
-
- rb_scan_args(argc, argv, "11", &data, &str);
-
- StringValue(data);
- in = (unsigned char *)RSTRING_PTR(data);
- if ((in_len = RSTRING_LENINT(data)) == 0)
- ossl_raise(rb_eArgError, "data must not be empty");
- GetCipher(self, ctx);
- out_len = in_len+EVP_CIPHER_CTX_block_size(ctx);
-
- if (NIL_P(str)) {
- str = rb_str_new(0, out_len);
- } else {
- StringValue(str);
- rb_str_resize(str, out_len);
- }
-
- if (!EVP_CipherUpdate(ctx, (unsigned char *)RSTRING_PTR(str), &out_len, in, in_len))
- ossl_raise(eCipherError, NULL);
- assert(out_len < RSTRING_LEN(str));
- rb_str_set_len(str, out_len);
-
- return str;
-}
-
-/*
- * call-seq:
- * cipher.final -> string
- *
- * Returns the remaining data held in the cipher object. Further calls to
- * Cipher#update or Cipher#final will return garbage.
- *
- * See EVP_CipherFinal_ex for further information.
- */
-static VALUE
-ossl_cipher_final(VALUE self)
-{
- EVP_CIPHER_CTX *ctx;
- int out_len;
- VALUE str;
-
- GetCipher(self, ctx);
- str = rb_str_new(0, EVP_CIPHER_CTX_block_size(ctx));
- if (!EVP_CipherFinal_ex(ctx, (unsigned char *)RSTRING_PTR(str), &out_len))
- ossl_raise(eCipherError, NULL);
- assert(out_len <= RSTRING_LEN(str));
- rb_str_set_len(str, out_len);
-
- return str;
-}
-
-/*
- * call-seq:
- * cipher.name -> string
- *
- * Returns the name of the cipher which may differ slightly from the original
- * name provided.
- */
-static VALUE
-ossl_cipher_name(VALUE self)
-{
- EVP_CIPHER_CTX *ctx;
-
- GetCipher(self, ctx);
-
- return rb_str_new2(EVP_CIPHER_name(EVP_CIPHER_CTX_cipher(ctx)));
-}
-
-/*
- * call-seq:
- * cipher.key = string -> string
- *
- * Sets the cipher key. To generate a key, you should either use a secure
- * random byte string or, if the key is to be derived from a password, you
- * should rely on PBKDF2 functionality provided by OpenSSL::PKCS5. To
- * generate a secure random-based key, Cipher#random_key may be used.
- *
- * Only call this method after calling Cipher#encrypt or Cipher#decrypt.
- */
-static VALUE
-ossl_cipher_set_key(VALUE self, VALUE key)
-{
- EVP_CIPHER_CTX *ctx;
-
- StringValue(key);
- GetCipher(self, ctx);
-
- if (RSTRING_LEN(key) < EVP_CIPHER_CTX_key_length(ctx))
- ossl_raise(eCipherError, "key length too short");
-
- if (EVP_CipherInit_ex(ctx, NULL, NULL, (unsigned char *)RSTRING_PTR(key), NULL, -1) != 1)
- ossl_raise(eCipherError, NULL);
-
- return key;
-}
-
-/*
- * call-seq:
- * cipher.iv = string -> string
- *
- * Sets the cipher IV. Please note that since you should never be using ECB
- * mode, an IV is always explicitly required and should be set prior to
- * encryption. The IV itself can be safely transmitted in public, but it
- * should be unpredictable to prevent certain kinds of attacks. You may use
- * Cipher#random_iv to create a secure random IV.
- *
- * Only call this method after calling Cipher#encrypt or Cipher#decrypt.
- *
- * If not explicitly set, the OpenSSL default of an all-zeroes ("\\0") IV is
- * used.
- */
-static VALUE
-ossl_cipher_set_iv(VALUE self, VALUE iv)
-{
- EVP_CIPHER_CTX *ctx;
-
- StringValue(iv);
- GetCipher(self, ctx);
-
- if (RSTRING_LEN(iv) < EVP_CIPHER_CTX_iv_length(ctx))
- ossl_raise(eCipherError, "iv length too short");
-
- if (EVP_CipherInit_ex(ctx, NULL, NULL, NULL, (unsigned char *)RSTRING_PTR(iv), -1) != 1)
- ossl_raise(eCipherError, NULL);
-
- return iv;
-}
-
-
-/*
- * call-seq:
- * cipher.key_len = integer -> integer
- *
- * Sets the key length of the cipher. If the cipher is a fixed length cipher
- * then attempting to set the key length to any value other than the fixed
- * value is an error.
- *
- * Under normal circumstances you do not need to call this method (and probably shouldn't).
- *
- * See EVP_CIPHER_CTX_set_key_length for further information.
- */
-static VALUE
-ossl_cipher_set_key_length(VALUE self, VALUE key_length)
-{
- int len = NUM2INT(key_length);
- EVP_CIPHER_CTX *ctx;
-
- GetCipher(self, ctx);
- if (EVP_CIPHER_CTX_set_key_length(ctx, len) != 1)
- ossl_raise(eCipherError, NULL);
-
- return key_length;
-}
-
-#if defined(HAVE_EVP_CIPHER_CTX_SET_PADDING)
-/*
- * call-seq:
- * cipher.padding = integer -> integer
- *
- * Enables or disables padding. By default encryption operations are padded using standard block padding and the
- * padding is checked and removed when decrypting. If the pad parameter is zero then no padding is performed, the
- * total amount of data encrypted or decrypted must then be a multiple of the block size or an error will occur.
- *
- * See EVP_CIPHER_CTX_set_padding for further information.
- */
-static VALUE
-ossl_cipher_set_padding(VALUE self, VALUE padding)
-{
- EVP_CIPHER_CTX *ctx;
- int pad = NUM2INT(padding);
-
- GetCipher(self, ctx);
- if (EVP_CIPHER_CTX_set_padding(ctx, pad) != 1)
- ossl_raise(eCipherError, NULL);
- return padding;
-}
-#else
-#define ossl_cipher_set_padding rb_f_notimplement
-#endif
-
-#define CIPHER_0ARG_INT(func) \
- static VALUE \
- ossl_cipher_##func(VALUE self) \
- { \
- EVP_CIPHER_CTX *ctx; \
- GetCipher(self, ctx); \
- return INT2NUM(EVP_CIPHER_##func(EVP_CIPHER_CTX_cipher(ctx))); \
- }
-
-/*
- * call-seq:
- * cipher.key_len -> integer
- *
- * Returns the key length in bytes of the Cipher.
- */
-CIPHER_0ARG_INT(key_length)
-/*
- * call-seq:
- * cipher.iv_len -> integer
- *
- * Returns the expected length in bytes for an IV for this Cipher.
- */
-CIPHER_0ARG_INT(iv_length)
-/*
- * call-seq:
- * cipher.block_size -> integer
- *
- * Returns the size in bytes of the blocks on which this Cipher operates on.
- */
-CIPHER_0ARG_INT(block_size)
-
-/*
- * INIT
- */
-void
-Init_ossl_cipher(void)
-{
-#if 0
- mOSSL = rb_define_module("OpenSSL"); /* let rdoc know about mOSSL */
-#endif
-
- /* Document-class: OpenSSL::Cipher
- *
- * Provides symmetric algorithms for encryption and decryption. The
- * algorithms that are available depend on the particular version
- * of OpenSSL that is installed.
- *
- * === Listing all supported algorithms
- *
- * A list of supported algorithms can be obtained by
- *
- * puts OpenSSL::Cipher.ciphers
- *
- * === Instantiating a Cipher
- *
- * There are several ways to create a Cipher instance. Generally, a
- * Cipher algorithm is categorized by its name, the key length in bits
- * and the cipher mode to be used. The most generic way to create a
- * Cipher is the following
- *
- * cipher = OpenSSL::Cipher.new('<name>-<key length>-<mode>')
- *
- * That is, a string consisting of the hyphenated concatenation of the
- * individual components name, key length and mode. Either all uppercase
- * or all lowercase strings may be used, for example:
- *
- * cipher = OpenSSL::Cipher.new('AES-128-CBC')
- *
- * For each algorithm supported, there is a class defined under the
- * Cipher class that goes by the name of the cipher, e.g. to obtain an
- * instance of AES, you could also use
- *
- * # these are equivalent
- * cipher = OpenSSL::Cipher::AES.new(128, :CBC)
- * cipher = OpenSSL::Cipher::AES.new(128, 'CBC')
- * cipher = OpenSSL::Cipher::AES.new('128-CBC')
- *
- * Finally, due to its wide-spread use, there are also extra classes
- * defined for the different key sizes of AES
- *
- * cipher = OpenSSL::Cipher::AES128.new(:CBC)
- * cipher = OpenSSL::Cipher::AES192.new(:CBC)
- * cipher = OpenSSL::Cipher::AES256.new(:CBC)
- *
- * === Choosing either encryption or decryption mode
- *
- * Encryption and decryption are often very similar operations for
- * symmetric algorithms, this is reflected by not having to choose
- * different classes for either operation, both can be done using the
- * same class. Still, after obtaining a Cipher instance, we need to
- * tell the instance what it is that we intend to do with it, so we
- * need to call either
- *
- * cipher.encrypt
- *
- * or
- *
- * cipher.decrypt
- *
- * on the Cipher instance. This should be the first call after creating
- * the instance, otherwise configuration that has already been set could
- * get lost in the process.
- *
- * === Choosing a key
- *
- * Symmetric encryption requires a key that is the same for the encrypting
- * and for the decrypting party and after initial key establishment should
- * be kept as private information. There are a lot of ways to create
- * insecure keys, the most notable is to simply take a password as the key
- * without processing the password further. A simple and secure way to
- * create a key for a particular Cipher is
- *
- * cipher = OpenSSL::AES256.new(:CFB)
- * cipher.encrypt
- * key = cipher.random_key # also sets the generated key on the Cipher
- *
- * If you absolutely need to use passwords as encryption keys, you
- * should use Password-Based Key Derivation Function 2 (PBKDF2) by
- * generating the key with the help of the functionality provided by
- * OpenSSL::PKCS5.pbkdf2_hmac_sha1 or OpenSSL::PKCS5.pbkdf2_hmac.
- *
- * Although there is Cipher#pkcs5_keyivgen, its use is deprecated and
- * it should only be used in legacy applications because it does not use
- * the newer PKCS#5 v2 algorithms.
- *
- * === Choosing an IV
- *
- * The cipher modes CBC, CFB, OFB and CTR all need an "initialization
- * vector", or short, IV. ECB mode is the only mode that does not require
- * an IV, but there is almost no legitimate use case for this mode
- * because of the fact that it does not sufficiently hide plaintext
- * patterns. Therefore
- *
- * <b>You should never use ECB mode unless you are absolutely sure that
- * you absolutely need it</b>
- *
- * Because of this, you will end up with a mode that explicitly requires
- * an IV in any case. Note that for backwards compatibility reasons,
- * setting an IV is not explicitly mandated by the Cipher API. If not
- * set, OpenSSL itself defaults to an all-zeroes IV ("\\0", not the
- * character). Although the IV can be seen as public information, i.e.
- * it may be transmitted in public once generated, it should still stay
- * unpredictable to prevent certain kinds of attacks. Therefore, ideally
- *
- * <b>Always create a secure random IV for every encryption of your
- * Cipher</b>
- *
- * A new, random IV should be created for every encryption of data. Think
- * of the IV as a nonce (number used once) - it's public but random and
- * unpredictable. A secure random IV can be created as follows
- *
- * cipher = ...
- * cipher.encrypt
- * key = cipher.random_key
- * iv = cipher.random_iv # also sets the generated IV on the Cipher
- *
- * Although the key is generally a random value, too, it is a bad choice
- * as an IV. There are elaborate ways how an attacker can take advantage
- * of such an IV. As a general rule of thumb, exposing the key directly
- * or indirectly should be avoided at all cost and exceptions only be
- * made with good reason.
- *
- * === Calling Cipher#final
- *
- * ECB (which should not be used) and CBC are both block-based modes.
- * This means that unlike for the other streaming-based modes, they
- * operate on fixed-size blocks of data, and therefore they require a
- * "finalization" step to produce or correctly decrypt the last block of
- * data by appropriately handling some form of padding. Therefore it is
- * essential to add the output of OpenSSL::Cipher#final to your
- * encryption/decryption buffer or you will end up with decryption errors
- * or truncated data.
- *
- * Although this is not really necessary for streaming-mode ciphers, it is
- * still recommended to apply the same pattern of adding the output of
- * Cipher#final there as well - it also enables you to switch between
- * modes more easily in the future.
- *
- * === Encrypting and decrypting some data
- *
- * data = "Very, very confidential data"
- *
- * cipher = OpenSSL::Cipher::AES.new(128, :CBC)
- * cipher.encrypt
- * key = cipher.random_key
- * iv = cipher.random_iv
- *
- * encrypted = cipher.update(data) + cipher.final
- * ...
- * decipher = OpenSSL::Cipher::AES.new(128, :CBC)
- * decipher.decrypt
- * decipher.key = key
- * decipher.iv = iv
- *
- * plain = decipher.update(encrypted) + decipher.final
- *
- * puts data == plain #=> true
- *
- */
- cCipher = rb_define_class_under(mOSSL, "Cipher", rb_cObject);
- eCipherError = rb_define_class_under(cCipher, "CipherError", eOSSLError);
-
- rb_define_alloc_func(cCipher, ossl_cipher_alloc);
- rb_define_copy_func(cCipher, ossl_cipher_copy);
- rb_define_module_function(cCipher, "ciphers", ossl_s_ciphers, 0);
- rb_define_method(cCipher, "initialize", ossl_cipher_initialize, 1);
- rb_define_method(cCipher, "reset", ossl_cipher_reset, 0);
- rb_define_method(cCipher, "encrypt", ossl_cipher_encrypt, -1);
- rb_define_method(cCipher, "decrypt", ossl_cipher_decrypt, -1);
- rb_define_method(cCipher, "pkcs5_keyivgen", ossl_cipher_pkcs5_keyivgen, -1);
- rb_define_method(cCipher, "update", ossl_cipher_update, -1);
- rb_define_method(cCipher, "final", ossl_cipher_final, 0);
- rb_define_method(cCipher, "name", ossl_cipher_name, 0);
- rb_define_method(cCipher, "key=", ossl_cipher_set_key, 1);
- rb_define_method(cCipher, "key_len=", ossl_cipher_set_key_length, 1);
- rb_define_method(cCipher, "key_len", ossl_cipher_key_length, 0);
- rb_define_method(cCipher, "iv=", ossl_cipher_set_iv, 1);
- rb_define_method(cCipher, "iv_len", ossl_cipher_iv_length, 0);
- rb_define_method(cCipher, "block_size", ossl_cipher_block_size, 0);
- rb_define_method(cCipher, "padding=", ossl_cipher_set_padding, 1);
-}
-