/* des.c - DES and Triple-DES encryption/decryption Algorithm * Copyright (C) 1998 Free Software Foundation, Inc. * * Please see below for more legal information! * * According to the definition of DES in FIPS PUB 46-2 from December 1993. * For a description of triple encryption, see: * Bruce Schneier: Applied Cryptography. Second Edition. * John Wiley & Sons, 1996. ISBN 0-471-12845-7. Pages 358 ff. * * This file is part of GNUPG. * * GNUPG is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * GNUPG is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA */ /* * Written by Michael Roth , September 1998 */ /* * U S A G E * =========== * * For DES or Triple-DES encryption/decryption you must initialize a proper * encryption context with a key. * * A DES key is 64bit wide but only 56bits of the key are used. The remaining * bits are parity bits and they will _not_ checked in this implementation, but * simply ignored. * * For Tripple-DES you could use either two 64bit keys or three 64bit keys. * The parity bits will _not_ checked, too. * * After initializing a context with a key you could use this context to * encrypt or decrypt data in 64bit blocks in Electronic Codebook Mode. * * (In the examples below the slashes at the beginning and ending of comments * are omited.) * * DES Example * ----------- * unsigned char key[8]; * unsigned char plaintext[8]; * unsigned char ciphertext[8]; * unsigned char recoverd[8]; * des_ctx context; * * * Fill 'key' and 'plaintext' with some data * * .... * * * Set up the DES encryption context * * des_setkey(context, key); * * * Encrypt the plaintext * * des_ecb_encrypt(context, plaintext, ciphertext); * * * To recover the orginal plaintext from ciphertext use: * * des_ecb_decrypt(context, ciphertext, recoverd); * * * Triple-DES Example * ------------------ * unsigned char key1[8]; * unsigned char key2[8]; * unsigned char key3[8]; * unsigned char plaintext[8]; * unsigned char ciphertext[8]; * unsigned char recoverd[8]; * tripledes_ctx context; * * * If you would like to use two 64bit keys, fill 'key1' and'key2' * then setup the encryption context: * * tripledes_set2keys(context, key1, key2); * * * To use three 64bit keys with Triple-DES use: * * tripledes_set3keys(context, key1, key2, key3); * * * Encrypting plaintext with Triple-DES * * tripledes_ecb_encrypt(context, plaintext, ciphertext); * * * Decrypting ciphertext to recover the plaintext with Triple-DES * * tripledes_ecb_decrypt(context, ciphertext, recoverd); * * * Selftest * -------- * char *error_msg; * * * To perform a selftest of this DES/Triple-DES implementation use the * function selftest(). It will return an error string if their are * some problems with this library. * * * if ( (error_msg = selftest()) ) * { * fprintf(stderr, "An error in the DES/Tripple-DES implementation occured: %s\n", error_msg); * abort(); * } */ #include #include /* memcpy, memcmp */ #include #include "types.h" /* for byte and u32 typedefs */ #include "util.h" /* for log_fatal() */ #include "des.h" /* Some defines/checks to support standalone modules */ #ifndef CIPHER_ALGO_3DES #define CIPHER_ALGO_3DES 2 #elif CIPHER_ALGO_3DES != 2 #error CIPHER_ALGO_3DES is defined to a wrong value. #endif #ifndef G10ERR_WEAK_KEY #define G10ERR_WEAK_KEY 43 #elif G10ERR_WEAK_KEY != 43 #error G10ERR_WEAK_KEY is defined to a wrong value. #endif #ifndef G10ERR_WRONG_KEYLEN #define G10ERR_WRONG_KEYLEN 44 #elif G10ERR_WRONG_KEYLEN != 44 #error G10ERR_WRONG_KEYLEN is defined to a wrong value. #endif /* Macros used by the info function. */ #define FNCCAST_SETKEY(f) ((int(*)(void*, byte*, unsigned))(f)) #define FNCCAST_CRYPT(f) ((void(*)(void*, byte*, byte*))(f)) /* * Encryption/Decryption context of DES */ typedef struct _des_ctx { u32 encrypt_subkeys[32]; u32 decrypt_subkeys[32]; } des_ctx[1]; /* * Encryption/Decryption context of Triple-DES */ typedef struct _tripledes_ctx { u32 encrypt_subkeys[96]; u32 decrypt_subkeys[96]; } tripledes_ctx[1]; static void des_key_schedule (const byte *, u32 *); static int des_setkey (struct _des_ctx *, const byte *); static int des_ecb_crypt (struct _des_ctx *, const byte *, byte *, int); static int tripledes_set2keys (struct _tripledes_ctx *, const byte *, const byte *); static int tripledes_set3keys (struct _tripledes_ctx *, const byte *, const byte *, const byte *); static int tripledes_ecb_crypt (struct _tripledes_ctx *, const byte *, byte *, int); static int is_weak_key ( const byte *key ); static const char *selftest (void); /* * The s-box values are permuted according to the 'primitive function P' */ static u32 sbox1[64] = { 0x00808200, 0x00000000, 0x00008000, 0x00808202, 0x00808002, 0x00008202, 0x00000002, 0x00008000, 0x00000200, 0x00808200, 0x00808202, 0x00000200, 0x00800202, 0x00808002, 0x00800000, 0x00000002, 0x00000202, 0x00800200, 0x00800200, 0x00008200, 0x00008200, 0x00808000, 0x00808000, 0x00800202, 0x00008002, 0x00800002, 0x00800002, 0x00008002, 0x00000000, 0x00000202, 0x00008202, 0x00800000, 0x00008000, 0x00808202, 0x00000002, 0x00808000, 0x00808200, 0x00800000, 0x00800000, 0x00000200, 0x00808002, 0x00008000, 0x00008200, 0x00800002, 0x00000200, 0x00000002, 0x00800202, 0x00008202, 0x00808202, 0x00008002, 0x00808000, 0x00800202, 0x00800002, 0x00000202, 0x00008202, 0x00808200, 0x00000202, 0x00800200, 0x00800200, 0x00000000, 0x00008002, 0x00008200, 0x00000000, 0x00808002 }; static u32 sbox2[64] = { 0x40084010, 0x40004000, 0x00004000, 0x00084010, 0x00080000, 0x00000010, 0x40080010, 0x40004010, 0x40000010, 0x40084010, 0x40084000, 0x40000000, 0x40004000, 0x00080000, 0x00000010, 0x40080010, 0x00084000, 0x00080010, 0x40004010, 0x00000000, 0x40000000, 0x00004000, 0x00084010, 0x40080000, 0x00080010, 0x40000010, 0x00000000, 0x00084000, 0x00004010, 0x40084000, 0x40080000, 0x00004010, 0x00000000, 0x00084010, 0x40080010, 0x00080000, 0x40004010, 0x40080000, 0x40084000, 0x00004000, 0x40080000, 0x40004000, 0x00000010, 0x40084010, 0x00084010, 0x00000010, 0x00004000, 0x40000000, 0x00004010, 0x40084000, 0x00080000, 0x40000010, 0x00080010, 0x40004010, 0x40000010, 0x00080010, 0x00084000, 0x00000000, 0x40004000, 0x00004010, 0x40000000, 0x40080010, 0x40084010, 0x00084000 }; static u32 sbox3[64] = { 0x00000104, 0x04010100, 0x00000000, 0x04010004, 0x04000100, 0x00000000, 0x00010104, 0x04000100, 0x00010004, 0x04000004, 0x04000004, 0x00010000, 0x04010104, 0x00010004, 0x04010000, 0x00000104, 0x04000000, 0x00000004, 0x04010100, 0x00000100, 0x00010100, 0x04010000, 0x04010004, 0x00010104, 0x04000104, 0x00010100, 0x00010000, 0x04000104, 0x00000004, 0x04010104, 0x00000100, 0x04000000, 0x04010100, 0x04000000, 0x00010004, 0x00000104, 0x00010000, 0x04010100, 0x04000100, 0x00000000, 0x00000100, 0x00010004, 0x04010104, 0x04000100, 0x04000004, 0x00000100, 0x00000000, 0x04010004, 0x04000104, 0x00010000, 0x04000000, 0x04010104, 0x00000004, 0x00010104, 0x00010100, 0x04000004, 0x04010000, 0x04000104, 0x00000104, 0x04010000, 0x00010104, 0x00000004, 0x04010004, 0x00010100 }; static u32 sbox4[64] = { 0x80401000, 0x80001040, 0x80001040, 0x00000040, 0x00401040, 0x80400040, 0x80400000, 0x80001000, 0x00000000, 0x00401000, 0x00401000, 0x80401040, 0x80000040, 0x00000000, 0x00400040, 0x80400000, 0x80000000, 0x00001000, 0x00400000, 0x80401000, 0x00000040, 0x00400000, 0x80001000, 0x00001040, 0x80400040, 0x80000000, 0x00001040, 0x00400040, 0x00001000, 0x00401040, 0x80401040, 0x80000040, 0x00400040, 0x80400000, 0x00401000, 0x80401040, 0x80000040, 0x00000000, 0x00000000, 0x00401000, 0x00001040, 0x00400040, 0x80400040, 0x80000000, 0x80401000, 0x80001040, 0x80001040, 0x00000040, 0x80401040, 0x80000040, 0x80000000, 0x00001000, 0x80400000, 0x80001000, 0x00401040, 0x80400040, 0x80001000, 0x00001040, 0x00400000, 0x80401000, 0x00000040, 0x00400000, 0x00001000, 0x00401040 }; static u32 sbox5[64] = { 0x00000080, 0x01040080, 0x01040000, 0x21000080, 0x00040000, 0x00000080, 0x20000000, 0x01040000, 0x20040080, 0x00040000, 0x01000080, 0x20040080, 0x21000080, 0x21040000, 0x00040080, 0x20000000, 0x01000000, 0x20040000, 0x20040000, 0x00000000, 0x20000080, 0x21040080, 0x21040080, 0x01000080, 0x21040000, 0x20000080, 0x00000000, 0x21000000, 0x01040080, 0x01000000, 0x21000000, 0x00040080, 0x00040000, 0x21000080, 0x00000080, 0x01000000, 0x20000000, 0x01040000, 0x21000080, 0x20040080, 0x01000080, 0x20000000, 0x21040000, 0x01040080, 0x20040080, 0x00000080, 0x01000000, 0x21040000, 0x21040080, 0x00040080, 0x21000000, 0x21040080, 0x01040000, 0x00000000, 0x20040000, 0x21000000, 0x00040080, 0x01000080, 0x20000080, 0x00040000, 0x00000000, 0x20040000, 0x01040080, 0x20000080 }; static u32 sbox6[64] = { 0x10000008, 0x10200000, 0x00002000, 0x10202008, 0x10200000, 0x00000008, 0x10202008, 0x00200000, 0x10002000, 0x00202008, 0x00200000, 0x10000008, 0x00200008, 0x10002000, 0x10000000, 0x00002008, 0x00000000, 0x00200008, 0x10002008, 0x00002000, 0x00202000, 0x10002008, 0x00000008, 0x10200008, 0x10200008, 0x00000000, 0x00202008, 0x10202000, 0x00002008, 0x00202000, 0x10202000, 0x10000000, 0x10002000, 0x00000008, 0x10200008, 0x00202000, 0x10202008, 0x00200000, 0x00002008, 0x10000008, 0x00200000, 0x10002000, 0x10000000, 0x00002008, 0x10000008, 0x10202008, 0x00202000, 0x10200000, 0x00202008, 0x10202000, 0x00000000, 0x10200008, 0x00000008, 0x00002000, 0x10200000, 0x00202008, 0x00002000, 0x00200008, 0x10002008, 0x00000000, 0x10202000, 0x10000000, 0x00200008, 0x10002008 }; static u32 sbox7[64] = { 0x00100000, 0x02100001, 0x02000401, 0x00000000, 0x00000400, 0x02000401, 0x00100401, 0x02100400, 0x02100401, 0x00100000, 0x00000000, 0x02000001, 0x00000001, 0x02000000, 0x02100001, 0x00000401, 0x02000400, 0x00100401, 0x00100001, 0x02000400, 0x02000001, 0x02100000, 0x02100400, 0x00100001, 0x02100000, 0x00000400, 0x00000401, 0x02100401, 0x00100400, 0x00000001, 0x02000000, 0x00100400, 0x02000000, 0x00100400, 0x00100000, 0x02000401, 0x02000401, 0x02100001, 0x02100001, 0x00000001, 0x00100001, 0x02000000, 0x02000400, 0x00100000, 0x02100400, 0x00000401, 0x00100401, 0x02100400, 0x00000401, 0x02000001, 0x02100401, 0x02100000, 0x00100400, 0x00000000, 0x00000001, 0x02100401, 0x00000000, 0x00100401, 0x02100000, 0x00000400, 0x02000001, 0x02000400, 0x00000400, 0x00100001 }; static u32 sbox8[64] = { 0x08000820, 0x00000800, 0x00020000, 0x08020820, 0x08000000, 0x08000820, 0x00000020, 0x08000000, 0x00020020, 0x08020000, 0x08020820, 0x00020800, 0x08020800, 0x00020820, 0x00000800, 0x00000020, 0x08020000, 0x08000020, 0x08000800, 0x00000820, 0x00020800, 0x00020020, 0x08020020, 0x08020800, 0x00000820, 0x00000000, 0x00000000, 0x08020020, 0x08000020, 0x08000800, 0x00020820, 0x00020000, 0x00020820, 0x00020000, 0x08020800, 0x00000800, 0x00000020, 0x08020020, 0x00000800, 0x00020820, 0x08000800, 0x00000020, 0x08000020, 0x08020000, 0x08020020, 0x08000000, 0x00020000, 0x08000820, 0x00000000, 0x08020820, 0x00020020, 0x08000020, 0x08020000, 0x08000800, 0x08000820, 0x00000000, 0x08020820, 0x00020800, 0x00020800, 0x00000820, 0x00000820, 0x00020020, 0x08000000, 0x08020800 }; /* * These two tables are part of the 'permuted choice 1' function. * In this implementation several speed improvements are done. */ u32 leftkey_swap[16] = { 0x00000000, 0x00000001, 0x00000100, 0x00000101, 0x00010000, 0x00010001, 0x00010100, 0x00010101, 0x01000000, 0x01000001, 0x01000100, 0x01000101, 0x01010000, 0x01010001, 0x01010100, 0x01010101 }; u32 rightkey_swap[16] = { 0x00000000, 0x01000000, 0x00010000, 0x01010000, 0x00000100, 0x01000100, 0x00010100, 0x01010100, 0x00000001, 0x01000001, 0x00010001, 0x01010001, 0x00000101, 0x01000101, 0x00010101, 0x01010101, }; /* * Numbers of left shifts per round for encryption subkey schedule * To calculate the decryption key scheduling we just reverse the * ordering of the subkeys so we can omit the table for decryption * subkey schedule. */ static byte encrypt_rotate_tab[16] = { 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 }; /* * Table with weak DES keys sorted in ascending order. * In DES their are 64 known keys wich are weak. They are weak * because they produce only one, two or four different * subkeys in the subkey scheduling process. * The keys in this table have all their parity bits cleared. */ static byte weak_keys[64][8] = { { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }, { 0x00, 0x00, 0x1e, 0x1e, 0x00, 0x00, 0x0e, 0x0e }, { 0x00, 0x00, 0xe0, 0xe0, 0x00, 0x00, 0xf0, 0xf0 }, { 0x00, 0x00, 0xfe, 0xfe, 0x00, 0x00, 0xfe, 0xfe }, { 0x00, 0x1e, 0x00, 0x1e, 0x00, 0x0e, 0x00, 0x0e }, { 0x00, 0x1e, 0x1e, 0x00, 0x00, 0x0e, 0x0e, 0x00 }, { 0x00, 0x1e, 0xe0, 0xfe, 0x00, 0x0e, 0xf0, 0xfe }, { 0x00, 0x1e, 0xfe, 0xe0, 0x00, 0x0e, 0xfe, 0xf0 }, { 0x00, 0xe0, 0x00, 0xe0, 0x00, 0xf0, 0x00, 0xf0 }, { 0x00, 0xe0, 0x1e, 0xfe, 0x00, 0xf0, 0x0e, 0xfe }, { 0x00, 0xe0, 0xe0, 0x00, 0x00, 0xf0, 0xf0, 0x00 }, { 0x00, 0xe0, 0xfe, 0x1e, 0x00, 0xf0, 0xfe, 0x0e }, { 0x00, 0xfe, 0x00, 0xfe, 0x00, 0xfe, 0x00, 0xfe }, { 0x00, 0xfe, 0x1e, 0xe0, 0x00, 0xfe, 0x0e, 0xf0 }, { 0x00, 0xfe, 0xe0, 0x1e, 0x00, 0xfe, 0xf0, 0x0e }, { 0x00, 0xfe, 0xfe, 0x00, 0x00, 0xfe, 0xfe, 0x00 }, { 0x0e, 0x0e, 0x0e, 0x0e, 0xf0, 0xf0, 0xf0, 0xf0 }, { 0x1e, 0x00, 0x00, 0x1e, 0x0e, 0x00, 0x00, 0x0e }, { 0x1e, 0x00, 0x1e, 0x00, 0x0e, 0x00, 0x0e, 0x00 }, { 0x1e, 0x00, 0xe0, 0xfe, 0x0e, 0x00, 0xf0, 0xfe }, { 0x1e, 0x00, 0xfe, 0xe0, 0x0e, 0x00, 0xfe, 0xf0 }, { 0x1e, 0x1e, 0x00, 0x00, 0x0e, 0x0e, 0x00, 0x00 }, { 0x1e, 0x1e, 0x1e, 0x1e, 0x0e, 0x0e, 0x0e, 0x0e }, { 0x1e, 0x1e, 0xe0, 0xe0, 0x0e, 0x0e, 0xf0, 0xf0 }, { 0x1e, 0x1e, 0xfe, 0xfe, 0x0e, 0x0e, 0xfe, 0xfe }, { 0x1e, 0xe0, 0x00, 0xfe, 0x0e, 0xf0, 0x00, 0xfe }, { 0x1e, 0xe0, 0x1e, 0xe0, 0x0e, 0xf0, 0x0e, 0xf0 }, { 0x1e, 0xe0, 0xe0, 0x1e, 0x0e, 0xf0, 0xf0, 0x0e }, { 0x1e, 0xe0, 0xfe, 0x00, 0x0e, 0xf0, 0xfe, 0x00 }, { 0x1e, 0xfe, 0x00, 0xe0, 0x0e, 0xfe, 0x00, 0xf0 }, { 0x1e, 0xfe, 0x1e, 0xfe, 0x0e, 0xfe, 0x0e, 0xfe }, { 0x1e, 0xfe, 0xe0, 0x00, 0x0e, 0xfe, 0xf0, 0x00 }, { 0x1e, 0xfe, 0xfe, 0x1e, 0x0e, 0xfe, 0xfe, 0x0e }, { 0xe0, 0x00, 0x00, 0xe0, 0xf0, 0x00, 0x00, 0xf0 }, { 0xe0, 0x00, 0x1e, 0xfe, 0xf0, 0x00, 0x0e, 0xfe }, { 0xe0, 0x00, 0xe0, 0x00, 0xf0, 0x00, 0xf0, 0x00 }, { 0xe0, 0x00, 0xfe, 0x1e, 0xf0, 0x00, 0xfe, 0x0e }, { 0xe0, 0x1e, 0x00, 0xfe, 0xf0, 0x0e, 0x00, 0xfe }, { 0xe0, 0x1e, 0x1e, 0xe0, 0xf0, 0x0e, 0x0e, 0xf0 }, { 0xe0, 0x1e, 0xe0, 0x1e, 0xf0, 0x0e, 0xf0, 0x0e }, { 0xe0, 0x1e, 0xfe, 0x00, 0xf0, 0x0e, 0xfe, 0x00 }, { 0xe0, 0xe0, 0x00, 0x00, 0xf0, 0xf0, 0x00, 0x00 }, { 0xe0, 0xe0, 0x1e, 0x1e, 0xf0, 0xf0, 0x0e, 0x0e }, { 0xe0, 0xe0, 0xfe, 0xfe, 0xf0, 0xf0, 0xfe, 0xfe }, { 0xe0, 0xfe, 0x00, 0x1e, 0xf0, 0xfe, 0x00, 0x0e }, { 0xe0, 0xfe, 0x1e, 0x00, 0xf0, 0xfe, 0x0e, 0x00 }, { 0xe0, 0xfe, 0xe0, 0xfe, 0xf0, 0xfe, 0xf0, 0xfe }, { 0xe0, 0xfe, 0xfe, 0xe0, 0xf0, 0xfe, 0xfe, 0xf0 }, { 0xfe, 0x00, 0x00, 0xfe, 0xfe, 0x00, 0x00, 0xfe }, { 0xfe, 0x00, 0x1e, 0xe0, 0xfe, 0x00, 0x0e, 0xf0 }, { 0xfe, 0x00, 0xe0, 0x1e, 0xfe, 0x00, 0xf0, 0x0e }, { 0xfe, 0x00, 0xfe, 0x00, 0xfe, 0x00, 0xfe, 0x00 }, { 0xfe, 0x1e, 0x00, 0xe0, 0xfe, 0x0e, 0x00, 0xf0 }, { 0xfe, 0x1e, 0x1e, 0xfe, 0xfe, 0x0e, 0x0e, 0xfe }, { 0xfe, 0x1e, 0xe0, 0x00, 0xfe, 0x0e, 0xf0, 0x00 }, { 0xfe, 0x1e, 0xfe, 0x1e, 0xfe, 0x0e, 0xfe, 0x0e }, { 0xfe, 0xe0, 0x00, 0x1e, 0xfe, 0xf0, 0x00, 0x0e }, { 0xfe, 0xe0, 0x1e, 0x00, 0xfe, 0xf0, 0x0e, 0x00 }, { 0xfe, 0xe0, 0xe0, 0xfe, 0xfe, 0xf0, 0xf0, 0xfe }, { 0xfe, 0xe0, 0xfe, 0xe0, 0xfe, 0xf0, 0xfe, 0xf0 }, { 0xfe, 0xfe, 0x00, 0x00, 0xfe, 0xfe, 0x00, 0x00 }, { 0xfe, 0xfe, 0x1e, 0x1e, 0xfe, 0xfe, 0x0e, 0x0e }, { 0xfe, 0xfe, 0xe0, 0xe0, 0xfe, 0xfe, 0xf0, 0xf0 }, { 0xfe, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe, 0xfe } }; /* * Macro to swap bits across two words */ #define DO_PERMUTATION(a, temp, b, offset, mask) \ temp = ((a>>offset) ^ b) & mask; \ b ^= temp; \ a ^= temp<>31)) ^ *subkey++; \ to ^= sbox8[ work & 0x3f ]; \ to ^= sbox6[ (work>>8) & 0x3f ]; \ to ^= sbox4[ (work>>16) & 0x3f ]; \ to ^= sbox2[ (work>>24) & 0x3f ]; \ work = ((from>>3) | (from<<29)) ^ *subkey++; \ to ^= sbox7[ work & 0x3f ]; \ to ^= sbox5[ (work>>8) & 0x3f ]; \ to ^= sbox3[ (work>>16) & 0x3f ]; \ to ^= sbox1[ (work>>24) & 0x3f ]; /* * Macros to convert 8 bytes from/to 32bit words */ #define READ_64BIT_DATA(data, left, right) \ left = (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3]; \ right = (data[4] << 24) | (data[5] << 16) | (data[6] << 8) | data[7]; #define WRITE_64BIT_DATA(data, left, right) \ data[0] = (left >> 24) &0xff; data[1] = (left >> 16) &0xff; \ data[2] = (left >> 8) &0xff; data[3] = left &0xff; \ data[4] = (right >> 24) &0xff; data[5] = (right >> 16) &0xff; \ data[6] = (right >> 8) &0xff; data[7] = right &0xff; /* * Handy macros for encryption and decryption of data */ #define des_ecb_encrypt(ctx, from, to) des_ecb_crypt(ctx, from, to, 0) #define des_ecb_decrypt(ctx, from, to) des_ecb_crypt(ctx, from, to, 1) #define tripledes_ecb_encrypt(ctx, from, to) tripledes_ecb_crypt(ctx, from, to, 0) #define tripledes_ecb_decrypt(ctx, from, to) tripledes_ecb_crypt(ctx, from, to, 1) /* * des_key_schedule(): Calculate 16 subkeys pairs (even/odd) for * 16 encryption rounds. * To calculate subkeys for decryption the caller * have to reorder the generated subkeys. * * rawkey: 8 Bytes of key data * subkey: Array of at least 32 u32s. Will be filled * with calculated subkeys. * */ static void des_key_schedule (const byte * rawkey, u32 * subkey) { u32 left, right, work; int round; READ_64BIT_DATA (rawkey, left, right) DO_PERMUTATION (right, work, left, 4, 0x0f0f0f0f) DO_PERMUTATION (right, work, left, 0, 0x10101010) left = (leftkey_swap[(left >> 0) & 0xf] << 3) | (leftkey_swap[(left >> 8) & 0xf] << 2) | (leftkey_swap[(left >> 16) & 0xf] << 1) | (leftkey_swap[(left >> 24) & 0xf]) | (leftkey_swap[(left >> 5) & 0xf] << 7) | (leftkey_swap[(left >> 13) & 0xf] << 6) | (leftkey_swap[(left >> 21) & 0xf] << 5) | (leftkey_swap[(left >> 29) & 0xf] << 4); left &= 0x0fffffff; right = (rightkey_swap[(right >> 1) & 0xf] << 3) | (rightkey_swap[(right >> 9) & 0xf] << 2) | (rightkey_swap[(right >> 17) & 0xf] << 1) | (rightkey_swap[(right >> 25) & 0xf]) | (rightkey_swap[(right >> 4) & 0xf] << 7) | (rightkey_swap[(right >> 12) & 0xf] << 6) | (rightkey_swap[(right >> 20) & 0xf] << 5) | (rightkey_swap[(right >> 28) & 0xf] << 4); right &= 0x0fffffff; for (round = 0; round < 16; ++round) { left = ((left << encrypt_rotate_tab[round]) | (left >> (28 - encrypt_rotate_tab[round]))) & 0x0fffffff; right = ((right << encrypt_rotate_tab[round]) | (right >> (28 - encrypt_rotate_tab[round]))) & 0x0fffffff; *subkey++ = ((left << 4) & 0x24000000) | ((left << 28) & 0x10000000) | ((left << 14) & 0x08000000) | ((left << 18) & 0x02080000) | ((left << 6) & 0x01000000) | ((left << 9) & 0x00200000) | ((left >> 1) & 0x00100000) | ((left << 10) & 0x00040000) | ((left << 2) & 0x00020000) | ((left >> 10) & 0x00010000) | ((right >> 13) & 0x00002000) | ((right >> 4) & 0x00001000) | ((right << 6) & 0x00000800) | ((right >> 1) & 0x00000400) | ((right >> 14) & 0x00000200) | (right & 0x00000100) | ((right >> 5) & 0x00000020) | ((right >> 10) & 0x00000010) | ((right >> 3) & 0x00000008) | ((right >> 18) & 0x00000004) | ((right >> 26) & 0x00000002) | ((right >> 24) & 0x00000001); *subkey++ = ((left << 15) & 0x20000000) | ((left << 17) & 0x10000000) | ((left << 10) & 0x08000000) | ((left << 22) & 0x04000000) | ((left >> 2) & 0x02000000) | ((left << 1) & 0x01000000) | ((left << 16) & 0x00200000) | ((left << 11) & 0x00100000) | ((left << 3) & 0x00080000) | ((left >> 6) & 0x00040000) | ((left << 15) & 0x00020000) | ((left >> 4) & 0x00010000) | ((right >> 2) & 0x00002000) | ((right << 8) & 0x00001000) | ((right >> 14) & 0x00000808) | ((right >> 9) & 0x00000400) | ((right) & 0x00000200) | ((right << 7) & 0x00000100) | ((right >> 7) & 0x00000020) | ((right >> 3) & 0x00000011) | ((right << 2) & 0x00000004) | ((right >> 21) & 0x00000002); } } /* * Fill a DES context with subkeys calculated from a 64bit key. * Does not check parity bits, but simply ignore them. * Does not check for weak keys. */ static int des_setkey (struct _des_ctx *ctx, const byte * key) { int i; des_key_schedule (key, ctx->encrypt_subkeys); for(i=0; i<32; i+=2) { ctx->decrypt_subkeys[i] = ctx->encrypt_subkeys[30-i]; ctx->decrypt_subkeys[i+1] = ctx->encrypt_subkeys[31-i]; } return 0; } /* * Electronic Codebook Mode DES encryption/decryption of data according * to 'mode'. */ static int des_ecb_crypt (struct _des_ctx *ctx, const byte * from, byte * to, int mode) { u32 left, right, work; u32 *keys; keys = mode ? ctx->decrypt_subkeys : ctx->encrypt_subkeys; READ_64BIT_DATA (from, left, right) INITIAL_PERMUTATION (left, work, right) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) FINAL_PERMUTATION (right, work, left) WRITE_64BIT_DATA (to, right, left) return 0; } /* * Fill a Triple-DES context with subkeys calculated from two 64bit keys. * Does not check the parity bits of the keys, but simply ignore them. * Does not check for weak keys. */ static int tripledes_set2keys (struct _tripledes_ctx *ctx, const byte * key1, const byte * key2) { int i; des_key_schedule (key1, ctx->encrypt_subkeys); des_key_schedule (key2, &(ctx->decrypt_subkeys[32])); for(i=0; i<32; i+=2) { ctx->decrypt_subkeys[i] = ctx->encrypt_subkeys[30-i]; ctx->decrypt_subkeys[i+1] = ctx->encrypt_subkeys[31-i]; ctx->encrypt_subkeys[i+32] = ctx->decrypt_subkeys[62-i]; ctx->encrypt_subkeys[i+33] = ctx->decrypt_subkeys[63-i]; ctx->encrypt_subkeys[i+64] = ctx->encrypt_subkeys[i]; ctx->encrypt_subkeys[i+65] = ctx->encrypt_subkeys[i+1]; ctx->decrypt_subkeys[i+64] = ctx->decrypt_subkeys[i]; ctx->decrypt_subkeys[i+65] = ctx->decrypt_subkeys[i+1]; } return 0; } /* * Fill a Triple-DES context with subkeys calculated from three 64bit keys. * Does not check the parity bits of the keys, but simply ignore them. * Does not check for weak keys. */ static int tripledes_set3keys (struct _tripledes_ctx *ctx, const byte * key1, const byte * key2, const byte * key3) { int i; des_key_schedule (key1, ctx->encrypt_subkeys); des_key_schedule (key2, &(ctx->decrypt_subkeys[32])); des_key_schedule (key3, &(ctx->encrypt_subkeys[64])); for(i=0; i<32; i+=2) { ctx->decrypt_subkeys[i] = ctx->encrypt_subkeys[94-i]; ctx->decrypt_subkeys[i+1] = ctx->encrypt_subkeys[95-i]; ctx->encrypt_subkeys[i+32] = ctx->decrypt_subkeys[62-i]; ctx->encrypt_subkeys[i+33] = ctx->decrypt_subkeys[63-i]; ctx->decrypt_subkeys[i+64] = ctx->encrypt_subkeys[30-i]; ctx->decrypt_subkeys[i+65] = ctx->encrypt_subkeys[31-i]; } return 0; } /* * Electronic Codebook Mode Triple-DES encryption/decryption of data according to 'mode'. * Sometimes this mode is named 'EDE' mode (Encryption-Decryption-Encryption). */ static int tripledes_ecb_crypt (struct _tripledes_ctx *ctx, const byte * from, byte * to, int mode) { u32 left, right, work; u32 *keys; keys = mode ? ctx->decrypt_subkeys : ctx->encrypt_subkeys; READ_64BIT_DATA (from, left, right) INITIAL_PERMUTATION (left, work, right) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) DES_ROUND (right, left, work, keys) DES_ROUND (left, right, work, keys) FINAL_PERMUTATION (right, work, left) WRITE_64BIT_DATA (to, right, left) return 0; } /* * Check whether the 8 byte key is weak. * Dose not check the parity bits of the key but simple ignore them. */ static int is_weak_key ( const byte *key ) { byte work[8]; int i, left, right, middle, cmp_result; /* clear parity bits */ for(i=0; i<8; ++i) work[i] = key[i] & 0xfe; /* binary search in the weak key table */ left = 0; right = 63; while(1) { middle = (left + right) / 2; if ( !(cmp_result=memcmp(work, weak_keys[middle], 8)) ) return -1; if ( left == right ) break; if ( cmp_result > 0 ) left = middle + 1; else right = middle - 1; } return 0; } /* * Performs a selftest of this DES/Triple-DES implementation. * Returns an string with the error text on failure. * Returns NULL if all is ok. */ static const char * selftest (void) { /* * Check if 'u32' is really 32 bits wide. This DES / 3DES implementation * need this. */ if (sizeof (u32) != 4) return "Wrong word size for DES configured."; /* * DES Maintenance Test */ { int i; byte key[8] = {0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55, 0x55}; byte input[8] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}; byte result[8] = {0x24, 0x6e, 0x9d, 0xb9, 0xc5, 0x50, 0x38, 0x1a}; byte temp1[8], temp2[8], temp3[8]; des_ctx des; for (i = 0; i < 64; ++i) { des_setkey (des, key); des_ecb_encrypt (des, input, temp1); des_ecb_encrypt (des, temp1, temp2); des_setkey (des, temp2); des_ecb_decrypt (des, temp1, temp3); memcpy (key, temp3, 8); memcpy (input, temp1, 8); } if (memcmp (temp3, result, 8)) return "DES maintenance test failed."; } /* * Triple-DES test (Do somebody known on official test?) * * FIXME: This test doesn't use tripledes_set3keys() ! */ { int i; byte input[8] = {0xfe, 0xdc, 0xba, 0x98, 0x76, 0x54, 0x32, 0x10}; byte key1[8] = {0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xf0}; byte key2[8] = {0x11, 0x22, 0x33, 0x44, 0xff, 0xaa, 0xcc, 0xdd}; byte result[8] = {0x7b, 0x38, 0x3b, 0x23, 0xa2, 0x7d, 0x26, 0xd3}; tripledes_ctx des3; for (i = 0; i < 16; ++i) { tripledes_set2keys (des3, key1, key2); tripledes_ecb_encrypt (des3, input, key1); tripledes_ecb_decrypt (des3, input, key2); tripledes_set3keys (des3, key1, input, key2); tripledes_ecb_encrypt (des3, input, input); } if (memcmp (input, result, 8)) return "TRIPLE-DES test failed."; } /* * Check the weak key detection. We simply assume the table with * weak keys is ok and check every key in the table if it is * detected... (This test is a little bit stupid) */ { int i; for (i = 0; i < 64; ++i) if (!is_weak_key(weak_keys[i])) return "DES weak key detection failed"; } return 0; } static int do_tripledes_setkey ( struct _tripledes_ctx *ctx, byte *key, unsigned keylen ) { if( keylen != 24 ) return G10ERR_WRONG_KEYLEN; tripledes_set3keys ( ctx, key, key+8, key+16); if( is_weak_key( key ) || is_weak_key( key+8 ) || is_weak_key( key+16 ) ) return G10ERR_WEAK_KEY; return 0; } static void do_tripledes_encrypt( struct _tripledes_ctx *ctx, byte *outbuf, byte *inbuf ) { tripledes_ecb_encrypt ( ctx, inbuf, outbuf ); } static void do_tripledes_decrypt( struct _tripledes_ctx *ctx, byte *outbuf, byte *inbuf ) { tripledes_ecb_decrypt ( ctx, inbuf, outbuf ); } /**************** * Return some information about the algorithm. We need algo here to * distinguish different flavors of the algorithm. * Returns: A pointer to string describing the algorithm or NULL if * the ALGO is invalid. */ const char * des_get_info( int algo, size_t *keylen, size_t *blocksize, size_t *contextsize, int (**r_setkey)( void *c, byte *key, unsigned keylen ), void (**r_encrypt)( void *c, byte *outbuf, byte *inbuf ), void (**r_decrypt)( void *c, byte *outbuf, byte *inbuf ) ) { static int did_selftest = 0; if( !did_selftest ) { const char *s = selftest(); if( s ) log_fatal("selftest failed: %s\n", s ); did_selftest = 1; } if( algo == CIPHER_ALGO_3DES ) { *keylen = 192; *blocksize = 8; *contextsize = sizeof(struct _tripledes_ctx); *r_setkey = FNCCAST_SETKEY(do_tripledes_setkey); *r_encrypt= FNCCAST_CRYPT(do_tripledes_encrypt); *r_decrypt= FNCCAST_CRYPT(do_tripledes_decrypt); return "3DES"; } return NULL; }