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Index: phpdoc/it/functions/mcrypt.xml diff -u phpdoc/it/functions/mcrypt.xml:1.3 phpdoc/it/functions/mcrypt.xml:1.4 --- phpdoc/it/functions/mcrypt.xml:1.3 Sat Jun 24 00:38:44 2000 +++ phpdoc/it/functions/mcrypt.xml Wed Dec 13 16:35:05 2000 @@ -1,10 +1,11 @@ - + mcrypt - These functions work using mcrypt. + These functions work using mcrypt. This is an interface to the mcrypt library, which supports a wide @@ -14,27 +15,56 @@ supports RC6 and IDEA which are considered "non-free". + If you linked against libmcrypt 2.4.x, the following additional + block algorithms are supported: CAST, LOKI97, RIJNDAEL, SAFERPLUS, + SERPENT and the following stream ciphers: ENIGMA (crypt), PANAMA, + RC4 and WAKE. With libmcrypt 2.4.x another cipher mode is also + available; nOFB. + + To use it, download libmcrypt-x.x.tar.gz from here and follow the included installation instructions. You need to compile PHP with the --with-mcrypt parameter to - enable this extension. + enable this extension. Make sure you compile libmcrypt with the + option --disable-posix-threads. + + + Mcrypt can be used to encrypt and decrypt using the above + mentioned ciphers. If you linked against libmcrypt-2.2.x, the + four important mcrypt commands (mcrypt_cfb, + mcrypt_cbc, mcrypt_ecb, + and mcrypt_ofb) can operate in both modes + which are named MCRYPT_ENCRYPT and MCRYPT_DECRYPT, respectively. + + + +<?php +$key = "this is a very secret key"; +$input = "Let us meet at 9 o'clock at the secret place."; + +$encrypted_data = mcrypt_ecb (MCRYPT_3DES, $key, $input, MCRYPT_ENCRYPT); +?> + + + This example will give you the encrypted data as a string in + $encrypted_data. - mcrypt can be used to encrypt and decrypt using the above - mentioned ciphers. The four important mcrypt commands - (mcrypt_cfb, mcrypt_cbc, - mcrypt_ecb, and - mcrypt_ofb) can operate in both modes which - are named MCRYPT_ENCRYPT and MCRYPT_DECRYPT, respectively. + If you linked against libmcrypt 2.4.x, these functions are still + available, but it is recommended that you use the advanced functions. - + <?php $key = "this is a very secret key"; $input = "Let us meet at 9 o'clock at the secret place."; -$encrypted_data = mcrypt_ecb(MCRYPT_TripleDES, $key, $input, MCRYPT_ENCRYPT); +$td = mcrypt_module_open (MCRYPT_TripleDES, "", MCRYPT_MODE_ECB, ""); +$iv = mcrypt_create_iv (mcrypt_enc_get_iv_size ($td), MCRYPT_RAND); +mcrypt_generic_init ($td, $key, $iv); +$encrypted_data = mcrypt_generic ($td, $input); +mcrypt_generic_end ($td); ?> @@ -42,9 +72,12 @@ $encrypted_data. - Mcrypt can operate in four cipher modes (CBC, OFB, CFB, and - ECB). We will outline the normal use for each of these modes. For - a more complete reference and discussion see + Mcrypt can operate in four block cipher modes (CBC, OFB, CFB, and + ECB). If linked against libmcrypt-2.4.x mcrypt can also operate + in the block cipher mode nOFB and in STREAM mode. Then there are + also constants in the form MCRYPT_MODE_mode for use with several + functions. We will outline the normal use for each of these modes. + For a more complete reference and discussion see &book.applied.cryptography;. @@ -69,10 +102,24 @@ + + OFB (output feedback, in 8bit) is comparable to CFB, but + can be used in applications where error propagation cannot + be tolerated. It's insecure (because it operates in 8bit + mode) so it is not recommended to use it. + + + + + nOFB (output feedback, in nbit) is comparable to OFB, but + more secure because it operates on the block size of the + algorithm. + + + - OFB (output feedback) is comparable to CFB, but can be used in - applications where error propagation cannot be - tolerated. + STREAM is an extra mode to include some stream algorithms + like WAKE or RC4. @@ -83,8 +130,11 @@ For a complete list of supported ciphers, see the defines at the - end of mcrypt.h. The general rule is that you - can access the cipher from PHP with MCRYPT_ciphername. + end of mcrypt.h. The general rule with the + mcrypt-2.2.x API is that you can access the cipher from PHP with + MCRYPT_ciphername. With the mcrypt-2.4.x API these constants also + work, but it is possible to specify the name of the cipher as + a string with a call to mcrypt_module_open. Here is a short list of ciphers which are currently supported by @@ -94,22 +144,52 @@ + MCRYPT_3DES + + + + + MCRYPT_ARCFOUR_IV (libmcrypt 2.4.x only) + + + + + MCRYPT_ARCFOUR (libmcrypt 2.4.x only) + + + + MCRYPT_BLOWFISH + MCRYPT_CAST_128 + + + + + MCRYPT_CAST_256 + + + + + MCRYPT_CRYPT + + + + MCRYPT_DES - MCRYPT_TripleDES + MCRYPT_DES_COMPAT (libmcrypt 2.2.x only) - MCRYPT_ThreeWAY + MCRYPT_ENIGMA (libmcrypt 2.4.x only, alias for MCRYPT_CRYPT) @@ -119,12 +199,67 @@ - MCRYPT_CRYPT + MCRYPT_IDEA (non-free) + + + + + MCRYPT_LOKI97 (libmcrypt 2.4.x only) + + + + + MCRYPT_MARS (libmcrypt 2.4.x only, non-free) + + + + + MCRYPT_PANAMA (libmcrypt 2.4.x only) + + + + + MCRYPT_RIJNDAEL_128 (libmcrypt 2.4.x only) + + + + + MCRYPT_RIJNDAEL_192 (libmcrypt 2.4.x only) + + + + + MCRYPT_RIJNDAEL_256 (libmcrypt 2.4.x only) + + + + + MCRYPT_RC2 + + + + + MCRYPT_RC4 (libmcrypt 2.2.x only) + + + + + MCRYPT_RC6 (libmcrypt 2.4.x only) + + + + + MCRYPT_RC6_128 (libmcrypt 2.2.x only) + + + + + MCRYPT_RC6_192 (libmcrypt 2.2.x only) - MCRYPT_DES_COMPAT + MCRYPT_RC6_256 (libmcrypt 2.2.x only) @@ -139,27 +274,57 @@ - MCRYPT_CAST128 + MCRYPT_SAFERPLUS (libmcrypt 2.4.x only) - MCRYPT_TEAN + MCRYPT_SERPENT (libmcrypt 2.4.x only) - MCRYPT_RC2 + MCRYPT_SERPENT_128 (libmcrypt 2.2.x only) + + + + + MCRYPT_SERPENT_192 (libmcrypt 2.2.x only) + + + + + MCRYPT_SERPENT_256 (libmcrypt 2.2.x only) + + + + + MCRYPT_SKIPJACK (libmcrypt 2.4.x only) + + + + + MCRYPT_TEAN (libmcrypt 2.2.x only) + + + + + MCRYPT_THREEWAY + + + + + MCRYPT_TRIPLEDES (libmcrypt 2.4.x only) - MCRYPT_TWOFISH (for older mcrypt 2.x versions) + MCRYPT_TWOFISH (for older mcrypt 2.x versions, or mcrypt 2.4.x ) - MCRYPT_TWOFISH128 (TWOFISHxxx are available in newer 2.x versions) + MCRYPT_TWOFISH128 (TWOFISHxxx are available in newer 2.x versions, but not in the 2.4.x versions) @@ -174,12 +339,12 @@ - MCRYPT_RC6 + MCRYPT_WAKE (libmcrypt 2.4.x only) - MCRYPT_IDEA + MCRYPT_XTEA (libmcrypt 2.4.x only) @@ -210,18 +375,25 @@ int cipher + + + string mcrypt_get_cipher_name + string cipher + + Mcrypt_get_cipher_name is used to get the name of the specified cipher. Mcrypt_get_cipher_name takes the cipher - number as an argument and returns the name of the cipher or - false, if the cipher does not exist. + number as an argument (libmcrypt 2.2.x) or takes the cipher name + as an argument (libmcrypt 2.4.x) and returns the name of the cipher + or false, if the cipher does not exist. - + <?php $cipher = MCRYPT_TripleDES; @@ -234,7 +406,7 @@ The above example will produce: -TripleDES +3DES @@ -252,14 +424,24 @@ int mcrypt_get_block_size int cipher + + int mcrypt_get_block_size + string cipher + string module + + + The first prototype is when linked against libmcrypt 2.2.x, the + second when linked against libmcrypt 2.4.x. + - Mcrypt_get_block_size is used to get the size of a - block of the specified cipher. + Mcrypt_get_block_size is used to get the + size of a block of the specified cipher. - Mcrypt_get_block_size takes one argument, the - cipher and returns the size in bytes. + Mcrypt_get_block_size takes one or two + arguments, the cipher and + module, and returns the size in bytes. See also: mcrypt_get_key_size. @@ -279,14 +461,24 @@ int mcrypt_get_key_size int cipher + + int mcrypt_get_key_size + string cipher + string module + + The first prototype is when linked against libmcrypt 2.2.x, the + second when linked against libmcrypt 2.4.x. + + Mcrypt_get_key_size is used to get the size of a key of the specified cipher. - mcrypt_get_key_size takes one argument, the - cipher and returns the size in bytes. + Mcrypt_get_key_size takes one or two + arguments, the cipher and + module, and returns the size in bytes. See also: mcrypt_get_block_size. @@ -360,6 +552,22 @@ + + + string mcrypt_cbc + string cipher + string key + string data + int mode + string + iv + + + + + The first prototype is when linked against libmcrypt 2.2.x, the + second when linked against libmcrypt 2.4.x. + Mcrypt_cbc encrypts or decrypts (depending on mode) the data @@ -409,6 +617,22 @@ string iv + + + string mcrypt_cfb + string cipher + string key + string data + int mode + string + iv + + + + + The first prototype is when linked against libmcrypt 2.2.x, the + second when linked against libmcrypt 2.4.x. + Mcrypt_cfb encrypts or decrypts (depending on mode) the data @@ -457,6 +681,22 @@ int mode + + + string mcrypt_ecb + string cipher + string key + string data + int mode + string + iv + + + + + The first prototype is when linked against libmcrypt 2.2.x, the + second when linked against libmcrypt 2.4.x. + Mcrypt_ecb encrypts or decrypts (depending on mode) the data @@ -503,7 +743,23 @@ string iv + + + string mcrypt_ofb + string cipher + string key + string data + int mode + string + iv + + + + The first prototype is when linked against libmcrypt 2.2.x, the + second when linked against libmcrypt 2.4.x. + + Mcrypt_ofb encrypts or decrypts (depending on mode) the data with cipher and key @@ -531,6 +787,829 @@ See also: mcrypt_cbc, mcrypt_cfb, and mcrypt_ecb. + + + + + + + mcrypt_list_algorithms + Get an array of all supported ciphers + + + + + + array mcrypt_list_algorithms + string + + lib_dir + + + + + + Mcrypt_list_algorithms is used to get an + array of all supported algorithms in the + + + lib_dir. + Mcrypt_list_algorithms takes as optional + parameter a directory which specifies the directory where all + algorithms are located. If not specifies, the value of the + mcrypt.algorithms_dir php.ini directive is used. + + + + + +<?php +$algorithms = mcrypt_list_algorithms ("/usr/local/lib/libmcrypt"); + +foreach ($algorithms as $cipher) { + echo $cipher."/n"; +} +?> + + + + + The above example will produce a list with all supported + algorithms in the "/usr/local/lib/libmcrypt" directory. + + + + + + + mcrypt_list_modes + Get an array of all supported modes + + + + + + array mcrypt_list_modes + string + + lib_dir + + + + + + Mcrypt_list_modes is used to get an + array of all supported modes in the + lib_dir. + + + Mcrypt_list_modes takes as optional + parameter a directory which specifies the directory where all + modes are located. If not specifies, the value of the + mcrypt.modes_dir php.ini directive is used. + + + + + +<?php +$modes = mcrypt_list_modes (); + +foreach ($modes as $mode) { + echo "$mode </br>"; +} +?> + + + + + The above example will produce a list with all supported + algorithms in the default mode directory. If it is not set + with the ini directive mcrypt.modes_dir, the default directory + of mcrypt is used (which is /usr/local/lib/libmcrypt). + + + + + + + mcrypt_get_iv_size + Returns the size of the IV belonging to a specific cipher/mode combination + + + + + + int mcrypt_get_iv_size + string cipher + string mode + + + int mcrypt_get_iv_size + resource td + + + + The first prototype is when linked against libmcrypt 2.2.x, the + second when linked against libmcrypt 2.4.x. + + + Mcrypt_get_iv_size returns the size of + the Initialisation Vector (IV) in bytes. On error the function + returns FALSE. If the IV is ignored in the specified cipher/mode + combination zero is returned. + + + Cipher is one of the MCRYPT_ciphername + constants of the name of the algorithm as string. + + + Mode is one of the MCRYPT_MODE_modename + constants of one of "ecb", "cbc", "cfb", "ofb", "nofb" or + "stream". + + + Td is the algorithm specified. + + + + + + + mcrypt_encrypt + Encrypts plaintext with given parameters + + + + + + string mcrypt_encrypt + string cipher + string key + string data + string mode + string + + iv + + + + + + Mcrypt_encrypt encrypts the data + and returns the encrypted data. + + + Cipher is one of the MCRYPT_ciphername + constants of the name of the algorithm as string. + + + Key is the key with which the data + will be encrypted. If it's smaller that the required keysize, it + is padded with '\0'. It is better not to use ASCII strings for + keys. It is recommended to use the mhash functions to create a key + from a string. + + + Data is the data that will be encrypted + with the given cipher and mode. If the size of the data is not + n * blocksize, the data will be padded with '\0'. The returned + crypttext can be larger that the size of the data that is given + by data. + + + Mode is one of the MCRYPT_MODE_modename + constants of one of "ecb", "cbc", "cfb", "ofb", "nofb" or + "stream". + + + The IV parameter is used for the + initialisation in CBC, CFB, OFB modes, and in some algorithms + in STREAM mode. If you do not supply an IV, while it is needed + for an algorithm, the function issues a warning and uses an + IV with all bytes set to '\0'. + + + + + +<?php +$iv = mcrypt_create_iv (mcrypt_get_iv_size (MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB), MCRYPT_RAND); +$key = "This is a very secret key"; +$text = "Meet me at 11 o'clock behind the monument."; +echo strlen ($text)."\n"; + +$crypttext = mcrypt_encrypt (MCRYPT_RIJNDAEL_256, $key, $text, MCRYPT_MODE_ECB, $iv); +echo strlen ($crypttext)."\n"; +?> + + + The above example will print out: + +42 +64 + + + + + + + + mcrypt_decrypt + Decrypts crypttext with given parameters + + + + + + string mcrypt_decrypt + string cipher + string key + string data + string mode + string + + iv + + + + + + Mcrypt_decrypt decrypts the data + and returns the unencrypted data. + + + Cipher is one of the MCRYPT_ciphername + constants of the name of the algorithm as string. + + + Key is the key with which the data + is encrypted. If it's smaller that the required keysize, it + is padded with '\0'. + + + Data is the data that will be decrypted + with the given cipher and mode. If the size of the data is not + n * blocksize, the data will be padded with '\0'. + + + Mode is one of the MCRYPT_MODE_modename + constants of one of "ecb", "cbc", "cfb", "ofb", "nofb" or + "stream". + + + The IV parameter is used for the + initialisation in CBC, CFB, OFB modes, and in some algorithms + in STREAM mode. If you do not supply an IV, while it is needed + for an algorithm, the function issues a warning and uses an + IV with all bytes set to '\0'. + + + + + + + mcrypt_module_open + This function opens the module of the algorithm and the mode to be used + + + + + + resource mcrypt_module_open + string algorithm + string algorithm_directory + string mode + string mode_directory + + + + This function opens the module of the algorithm and the mode + to be used. The name of the algorithm is specified in algorithm, + eg "twofish" or is one of the MCRYPT_ciphername constants. + The library is closed by calling + mcrypt_module_close, but there is no need + to call that function if mcrypt_generic_end + is called. Normally it returns an encryption descriptor, or + FALSE on error. + + + The algorithm_directory and + mode_directory are used to locate the + encryption modules. When you supply a directory name, it is used. + When you set one of these to the empty string (""), the value set + by the mcrypt.algorithms_dir or + mcrypt.modes_dir ini-directive is used. + When these are not set, the default directory are used that are + compiled in into libmcrypt (usally /usr/local/lib/libmcrypt). + + + + + +<?php +$td = mcrypt_module_open (MCRYPT_DES, "", MCRYPT_MODE_ECB, "/usr/lib/mcrypt-modes"); +?> + + + The above example will try to open the DES cipher from the default + directory and the EBC mode from the directory /usr/lib/mcrypt-modes. + + + + + + + mcrypt_generic_init + This function initializes all buffers needed for encryption + + + + + + int mcrypt_generic_init + resource td + string key + string iv + + + + The maximum length of the key should be the one obtained by + calling mcrypt_enc_get_key_size and every + value smaller than this is legal. The IV should normally have + the size of the algorithms block size, but you must obtain the + size by calling mcrypt_enc_get_iv_size. + IV is ignored in ECB. IV MUST exist in CFB, CBC, STREAM, nOFB + and OFB modes. It needs to be random and unique (but not secret). + The same IV must be used for encryption/decryption. If you do not + want to use it you should set it to zeros, but this is not + recommended. The function returns (-1) on error. + + + You need to call this function before every + mcrypt_generic or + mdecrypt_generic. + + + + + + + mcrypt_generic + This function encrypts data + + + + + + string mcrypt_generic + resource td + string data + + + + This function encrypts data. The data is padded with "\0" + to make sure the length of the data is n * blocksize. This + function returns the encrypted data. Note that the length + of the returned string can in fact be longer then the input, + due to the padding of the data. + + + + + + + mdecrypt_generic + This function decrypts data + + + + + + string mdecrypt_generic + resource td + string data + + + + This function decrypts data. Note that the length of the + returned string can in fact be longer then the unencrypted + string, due to the padding of the data. + + + + + +<?php +$iv_size = mcrypt_enc_get_iv_size ($td)); +$iv =  <email protected> ($iv_size, MCRYPT_RAND); + +if ( <email protected> ($td, $key, $iv) != -1) +{ + $c_t = mcrypt_generic ($td, $plain_text); +  <email protected> ($td, $key, $iv); + $p_t = mdecrypt_generic ($td, $c_t); +} +if (strncmp ($p_t, $plain_text, strlen($plain_text)) == 0) + echo "ok"; +else + echo "error"; +?> + + + The above example shows how to check if the data before the + encryption is the same as the data after the decryption. + + + + + + + mcrypt_generic_end + This function terminates encryption + + + + + + bool mcrypt_generic_end + resource td + + + + This function terminates encryption specified by the encryption + descriptor (td). Actually it clears all buffers, and closes + all the modules used. Returns FALSE on error, or TRUE on succes. + + + + + + + mcrypt_enc_self_test + This function runs a self test on the opened module + + + + + + int mcrypt_enc_self_test + resource td + + + + This function runs the self test on the algorithm specified by the + descriptor td. If the self test succeeds it returns zero. In case + of an error, it returns 1. + + + + + + + mcrypt_enc_is_block_algorithm_mode + Checks whether the encryption of the opened mode works on blocks + + + + + + int mcrypt_enc_is_block_algorithm_mode + resource td + + + + This function returns 1 if the mode is for use with block algorithms, + otherwise it returns 0. (eg. 0 for stream, and 1 for cbc, cfb, ofb). + + + + + + + mcrypt_enc_is_block_algorithm + Checks whether the algorithm of the opened mode is a block algorithm + + + + + + int mcrypt_enc_is_block_algorithm + resource td + + + + This function returns 1 if the algorithm is a block algorithm, + or 0 if it is a stream algorithm. + + + + + + + mcrypt_enc_is_block_mode + Checks whether the opened mode outputs blocks + + + + + + int mcrypt_enc_is_block_mode + resource td + + + + This function returns 1 if the mode outputs blocks of bytes or + 0 if it outputs bytes. (eg. 1 for cbc and ecb, and 0 for cfb and + stream). + + + + + + + mcrypt_enc_get_block_size + Returns the blocksize of the opened algorithm + + + + + + int mcrypt_enc_get_block_size + resource td + + + + This function returns the block size of the algorithm specified by + the encryption descriptor td in bytes. + + + + + + + mcrypt_enc_get_key_size + Returns the maximum supported keysize of the opened mode + + + + + + int mcrypt_enc_get_key_size + resource td + + + + This function returns the maximum supported key size of the + algorithm specified by the encryption descriptor td in bytes. + + + + + + + mcrypt_enc_get_supported_key_sizes + Returns an array with the supported keysizes of the opened algorithm + + + + + + array mcrypt_enc_get_supported_key_sizes + resource td + + + + Returns an array with the key sizes supported by the algorithm + specified by the encryption descriptor. If it returns an empty + array then all key sizes between 1 and + mcrypt_enc_get_key_size are supported by the + algorithm. + + + + + + + mcrypt_enc_get_iv_size + Returns the size of the IV of the opened algorithm + + + + + + int mcrypt_enc_get_iv_size + resource td + + + + This function returns the size of the iv of the algorithm + specified by the encryption descriptor in bytes. If it returns + '0' then the IV is ignored in the algorithm. An IV is used in + cbc, cfb and ofb modes, and in some algorithms in stream mode. + + + + + + + mcrypt_enc_get_algorithms_name + Returns the name of the opened algorithm + + + + + + string mcrypt_enc_get_algorithms_name + resource td + + + + This function returns the name of the algorithm. + + + + + + + mcrypt_enc_get_modes_name + Returns the name of the opened mode + + + + + + string mcrypt_enc_get_modes_name + resource td + + + + This function returns the name of the mode. + + + + + + + mcrypt_module_self_test + This function runs a self test on the specified module + + + + + + bool mcrypt_module_self_test + string algorithm + string lib_dir + + + + This function runs the self test on the algorithm specified. + The optional lib_dir parameter can contain + the location of where the algorithm module is on the system. + + + The function returns TRUE if the self test succeeds, or FALSE when + if fails. + + + + + + + mcrypt_module_is_block_algorithm_mode + This function returns if the the specified module is a block algorithm or not + + + + + + bool mcrypt_module_is_block_algorithm_mode + string mode + string lib_dir + + + + This function returns TRUE if the mode is for use with block algorithms, + otherwise it returns 0. (eg. 0 for stream, and 1 for cbc, cfb, ofb). + The optional lib_dir parameter can contain + the location where the mode module is on the system. + + + + + + + mcrypt_module_is_block_algorithm + This function checks whether the specified algorithm is a block algorithm + + + + + + bool mcrypt_module_is_block_algorithm + string algorithm + string lib_dir + + + + This function returns TRUE if the specified algorithm is a block + algorithm, or FALSE is it is a stream algorithm. + The optional lib_dir parameter can contain + the location where the algorithm module is on the system. + + + + + + + mcrypt_module_is_block_mode + This function returns if the the specified mode outputs blocks or not + + + + + + bool mcrypt_module_is_block_mode + string mode + string lib_dir + + + + This function returns TRUE if the mode outputs blocks of bytes or + FALSE if it outputs just bytes. (eg. 1 for cbc and ecb, and 0 for cfb + and stream). The optional lib_dir parameter + can contain the location where the mode module is on the system. + + + + + + + mcrypt_module_get_algo_block_size + Returns the blocksize of the specified algorithm + + + + + + int mcrypt_module_get_algo_block_size + string algorithm + string lib_dir + + + + This function returns the block size of the algorithm specified in + bytes. The optional lib_dir parameter + can contain the location where the mode module is on the system. + + + + + + + mcrypt_module_get_algo_key_size + Returns the maximum supported keysize of the opened mode + + + + + + int mcrypt_module_get_algo_key_size + string algorithm + string lib_dir + + + + This function returns the maximum supported key size of the + algorithm specified in bytes. The optional + lib_dir parameter can contain the + location where the mode module is on the system. + + + + + + + mcrypt_module_get_algo_supported_key_sizes + Returns an array with the supported keysizes of the opened algorithm + + + + + + array mcrypt_module_enc_get_algo_supported_key_sizes + string algorithm + string lib_dir + + + + Returns an array with the key sizes supported by the specified + algorithm. If it returns an empty array then all key sizes + between 1 and mcrypt_module_get_algo_key_size + are supported by the algorithm. The optional + lib_dir parameter can contain the + location where the mode module is on the system.