116Salm/* cbc.c: This file contains the encryption routines for the ed line editor */ 216Salm/*- 31057Salm * Copyright (c) 1993 The Regents of the University of California. 416Salm * All rights reserved. 516Salm * 61057Salm * Copyright (c) 1993 Andrew Moore, Talke Studio. 71057Salm * All rights reserved. 816Salm * 916Salm * Redistribution and use in source and binary forms, with or without 1016Salm * modification, are permitted provided that the following conditions 1116Salm * are met: 1216Salm * 1. Redistributions of source code must retain the above copyright 1316Salm * notice, this list of conditions and the following disclaimer. 1416Salm * 2. Redistributions in binary form must reproduce the above copyright 1516Salm * notice, this list of conditions and the following disclaimer in the 1616Salm * documentation and/or other materials provided with the distribution. 1716Salm * 4. Neither the name of the University nor the names of its contributors 1816Salm * may be used to endorse or promote products derived from this software 1916Salm * without specific prior written permission. 2016Salm * 2116Salm * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2216Salm * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2316Salm * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2416Salm * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2516Salm * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2616Salm * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2716Salm * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2816Salm * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2916Salm * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 3016Salm * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 3116Salm * SUCH DAMAGE. 3216Salm */ 3316Salm 3499109Sobrien#include <sys/cdefs.h> 3599109Sobrien__FBSDID("$FreeBSD: releng/11.0/bin/ed/cbc.c 300340 2016-05-21 00:45:42Z pfg $"); 3616Salm 371057Salm#include <sys/types.h> 3816Salm#include <errno.h> 3916Salm#include <pwd.h> 4027963Ssteve#ifdef DES 4127963Ssteve#include <time.h> 42115717Smarkm#include <openssl/des.h> 43115717Smarkm#define ED_DES_INCLUDES 4427963Ssteve#endif 4516Salm 4616Salm#include "ed.h" 4716Salm 481057Salm 4916Salm/* 5016Salm * BSD and System V systems offer special library calls that do 511057Salm * block move_liness and fills, so if possible we take advantage of them 5216Salm */ 5316Salm#define MEMCPY(dest,src,len) memcpy((dest),(src),(len)) 5416Salm#define MEMZERO(dest,len) memset((dest), 0, (len)) 5516Salm 5616Salm/* Hide the calls to the primitive encryption routines. */ 57101093Smarkm#define DES_XFORM(buf) \ 58115717Smarkm DES_ecb_encrypt(buf, buf, &schedule, \ 59115717Smarkm inverse ? DES_DECRYPT : DES_ENCRYPT); 6016Salm 6116Salm/* 6216Salm * read/write - no error checking 6316Salm */ 6416Salm#define READ(buf, n, fp) fread(buf, sizeof(char), n, fp) 6516Salm#define WRITE(buf, n, fp) fwrite(buf, sizeof(char), n, fp) 6616Salm 6716Salm/* 6816Salm * global variables and related macros 6916Salm */ 7016Salm 71115777Sjhay#ifdef DES 72241720Sedstatic DES_cblock ivec; /* initialization vector */ 73241720Sedstatic DES_cblock pvec; /* padding vector */ 74115717Smarkm 75241720Sedstatic char bits[] = { /* used to extract bits from a char */ 7616Salm '\200', '\100', '\040', '\020', '\010', '\004', '\002', '\001' 7716Salm}; 78115717Smarkm 79241720Sedstatic int pflag; /* 1 to preserve parity bits */ 8016Salm 81241720Sedstatic DES_key_schedule schedule; /* expanded DES key */ 82115717Smarkm 83241720Sedstatic unsigned char des_buf[8];/* shared buffer for get_des_char/put_des_char */ 84241720Sedstatic int des_ct = 0; /* count for get_des_char/put_des_char */ 85241720Sedstatic int des_n = 0; /* index for put_des_char/get_des_char */ 86248656Sjmg#endif 8716Salm 881057Salm/* init_des_cipher: initialize DES */ 8916Salmvoid 9090109Simpinit_des_cipher(void) 9116Salm{ 9216Salm#ifdef DES 9316Salm des_ct = des_n = 0; 9416Salm 957165Sjoerg /* initialize the initialization vector */ 9616Salm MEMZERO(ivec, 8); 9716Salm 9846684Skris /* initialize the padding vector */ 99300340Spfg arc4random_buf(pvec, sizeof(pvec)); 10016Salm#endif 10116Salm} 10216Salm 10316Salm 1041057Salm/* get_des_char: return next char in an encrypted file */ 1051057Salmint 10690109Simpget_des_char(FILE *fp) 10716Salm{ 10816Salm#ifdef DES 10916Salm if (des_n >= des_ct) { 11016Salm des_n = 0; 1111057Salm des_ct = cbc_decode(des_buf, fp); 11216Salm } 11316Salm return (des_ct > 0) ? des_buf[des_n++] : EOF; 1147165Sjoerg#else 1157165Sjoerg return (getc(fp)); 11616Salm#endif 11716Salm} 11816Salm 11916Salm 1201057Salm/* put_des_char: write a char to an encrypted file; return char written */ 1211057Salmint 12290109Simpput_des_char(int c, FILE *fp) 12316Salm{ 12416Salm#ifdef DES 12516Salm if (des_n == sizeof des_buf) { 1261057Salm des_ct = cbc_encode(des_buf, des_n, fp); 12716Salm des_n = 0; 12816Salm } 12916Salm return (des_ct >= 0) ? (des_buf[des_n++] = c) : EOF; 1307165Sjoerg#else 1317165Sjoerg return (fputc(c, fp)); 13216Salm#endif 13316Salm} 13416Salm 13516Salm 1361057Salm/* flush_des_file: flush an encrypted file's output; return status */ 1371057Salmint 13890109Simpflush_des_file(FILE *fp) 13916Salm{ 14016Salm#ifdef DES 14116Salm if (des_n == sizeof des_buf) { 1421057Salm des_ct = cbc_encode(des_buf, des_n, fp); 14316Salm des_n = 0; 14416Salm } 1451057Salm return (des_ct >= 0 && cbc_encode(des_buf, des_n, fp) >= 0) ? 0 : EOF; 1467165Sjoerg#else 1477165Sjoerg return (fflush(fp)); 14816Salm#endif 14916Salm} 15016Salm 15116Salm#ifdef DES 15216Salm/* 15316Salm * get keyword from tty or stdin 15416Salm */ 1551057Salmint 15690109Simpget_keyword(void) 15716Salm{ 15881220Smike char *p; /* used to obtain the key */ 159115717Smarkm DES_cblock msgbuf; /* I/O buffer */ 16016Salm 16116Salm /* 16216Salm * get the key 16316Salm */ 164300322Spfg if ((p = getpass("Enter key: ")) != NULL && *p != '\0') { 16516Salm 16616Salm /* 16716Salm * copy it, nul-padded, into the key area 16816Salm */ 169115717Smarkm expand_des_key(msgbuf, p); 17016Salm MEMZERO(p, _PASSWORD_LEN); 171115717Smarkm set_des_key(&msgbuf); 17216Salm MEMZERO(msgbuf, sizeof msgbuf); 17316Salm return 1; 17416Salm } 17516Salm return 0; 17616Salm} 17716Salm 17816Salm 17916Salm/* 18016Salm * print a warning message and, possibly, terminate 18116Salm */ 18216Salmvoid 18390109Simpdes_error(const char *s) 18416Salm{ 18581220Smike errmsg = s ? s : strerror(errno); 18616Salm} 18716Salm 18816Salm/* 18916Salm * map a hex character to an integer 19016Salm */ 1911057Salmint 19290109Simphex_to_binary(int c, int radix) 19316Salm{ 19416Salm switch(c) { 19516Salm case '0': return(0x0); 19616Salm case '1': return(0x1); 19716Salm case '2': return(radix > 2 ? 0x2 : -1); 19816Salm case '3': return(radix > 3 ? 0x3 : -1); 19916Salm case '4': return(radix > 4 ? 0x4 : -1); 20016Salm case '5': return(radix > 5 ? 0x5 : -1); 20116Salm case '6': return(radix > 6 ? 0x6 : -1); 20216Salm case '7': return(radix > 7 ? 0x7 : -1); 20316Salm case '8': return(radix > 8 ? 0x8 : -1); 20416Salm case '9': return(radix > 9 ? 0x9 : -1); 20516Salm case 'A': case 'a': return(radix > 10 ? 0xa : -1); 20616Salm case 'B': case 'b': return(radix > 11 ? 0xb : -1); 20716Salm case 'C': case 'c': return(radix > 12 ? 0xc : -1); 20816Salm case 'D': case 'd': return(radix > 13 ? 0xd : -1); 20916Salm case 'E': case 'e': return(radix > 14 ? 0xe : -1); 21016Salm case 'F': case 'f': return(radix > 15 ? 0xf : -1); 21116Salm } 21216Salm /* 21316Salm * invalid character 21416Salm */ 21516Salm return(-1); 21616Salm} 21716Salm 21816Salm/* 21916Salm * convert the key to a bit pattern 22090109Simp * obuf bit pattern 22190109Simp * kbuf the key itself 22216Salm */ 22316Salmvoid 22490109Simpexpand_des_key(char *obuf, char *kbuf) 22516Salm{ 22681220Smike int i, j; /* counter in a for loop */ 22716Salm int nbuf[64]; /* used for hex/key translation */ 22816Salm 22916Salm /* 23016Salm * leading '0x' or '0X' == hex key 23116Salm */ 23281220Smike if (kbuf[0] == '0' && (kbuf[1] == 'x' || kbuf[1] == 'X')) { 23381220Smike kbuf = &kbuf[2]; 23416Salm /* 23516Salm * now translate it, bombing on any illegal hex digit 23616Salm */ 237270256Spfg for (i = 0; i < 16 && kbuf[i]; i++) 23881220Smike if ((nbuf[i] = hex_to_binary((int) kbuf[i], 16)) == -1) 2391057Salm des_error("bad hex digit in key"); 24016Salm while (i < 16) 24116Salm nbuf[i++] = 0; 24216Salm for (i = 0; i < 8; i++) 24316Salm obuf[i] = 24416Salm ((nbuf[2*i]&0xf)<<4) | (nbuf[2*i+1]&0xf); 24516Salm /* preserve parity bits */ 24616Salm pflag = 1; 24716Salm return; 24816Salm } 24916Salm /* 25016Salm * leading '0b' or '0B' == binary key 25116Salm */ 25281220Smike if (kbuf[0] == '0' && (kbuf[1] == 'b' || kbuf[1] == 'B')) { 25381220Smike kbuf = &kbuf[2]; 25416Salm /* 25516Salm * now translate it, bombing on any illegal binary digit 25616Salm */ 257298640Spfg for (i = 0; i < 16 && kbuf[i]; i++) 25881220Smike if ((nbuf[i] = hex_to_binary((int) kbuf[i], 2)) == -1) 2591057Salm des_error("bad binary digit in key"); 26016Salm while (i < 64) 26116Salm nbuf[i++] = 0; 26216Salm for (i = 0; i < 8; i++) 26316Salm for (j = 0; j < 8; j++) 26416Salm obuf[i] = (obuf[i]<<1)|nbuf[8*i+j]; 26516Salm /* preserve parity bits */ 26616Salm pflag = 1; 26716Salm return; 26816Salm } 26916Salm /* 27016Salm * no special leader -- ASCII 27116Salm */ 27281220Smike (void)strncpy(obuf, kbuf, 8); 27316Salm} 27416Salm 27516Salm/***************** 27616Salm * DES FUNCTIONS * 27716Salm *****************/ 27816Salm/* 27916Salm * This sets the DES key and (if you're using the deszip version) 28016Salm * the direction of the transformation. This uses the Sun 28116Salm * to map the 64-bit key onto the 56 bits that the key schedule 28216Salm * generation routines use: the old way, which just uses the user- 28316Salm * supplied 64 bits as is, and the new way, which resets the parity 28416Salm * bit to be the same as the low-order bit in each character. The 28516Salm * new way generates a greater variety of key schedules, since many 28616Salm * systems set the parity (high) bit of each character to 0, and the 28716Salm * DES ignores the low order bit of each character. 28816Salm */ 28916Salmvoid 290115717Smarkmset_des_key(DES_cblock *buf) /* key block */ 29116Salm{ 29281220Smike int i, j; /* counter in a for loop */ 29381220Smike int par; /* parity counter */ 29416Salm 29516Salm /* 29616Salm * if the parity is not preserved, flip it 29716Salm */ 29816Salm if (!pflag) { 29916Salm for (i = 0; i < 8; i++) { 30016Salm par = 0; 30116Salm for (j = 1; j < 8; j++) 302115717Smarkm if ((bits[j] & (*buf)[i]) != 0) 30316Salm par++; 304115717Smarkm if ((par & 0x01) == 0x01) 305115717Smarkm (*buf)[i] &= 0x7f; 30616Salm else 307115717Smarkm (*buf)[i] = ((*buf)[i] & 0x7f) | 0x80; 30816Salm } 30916Salm } 31016Salm 311115717Smarkm DES_set_odd_parity(buf); 312115717Smarkm DES_set_key(buf, &schedule); 31316Salm} 31416Salm 31516Salm 31616Salm/* 31716Salm * This encrypts using the Cipher Block Chaining mode of DES 31816Salm */ 3191057Salmint 320101093Smarkmcbc_encode(unsigned char *msgbuf, int n, FILE *fp) 32116Salm{ 32216Salm int inverse = 0; /* 0 to encrypt, 1 to decrypt */ 32316Salm 32416Salm /* 32516Salm * do the transformation 32616Salm */ 32716Salm if (n == 8) { 32816Salm for (n = 0; n < 8; n++) 329115717Smarkm msgbuf[n] ^= ivec[n]; 330115717Smarkm DES_XFORM((DES_cblock *)msgbuf); 331115717Smarkm MEMCPY(ivec, msgbuf, 8); 332115717Smarkm return WRITE(msgbuf, 8, fp); 33316Salm } 33416Salm /* 33516Salm * at EOF or last block -- in either case, the last byte contains 33616Salm * the character representation of the number of bytes in it 33716Salm */ 33816Salm/* 33916Salm MEMZERO(msgbuf + n, 8 - n); 34016Salm*/ 34116Salm /* 34216Salm * Pad the last block randomly 34316Salm */ 344115717Smarkm (void)MEMCPY(msgbuf + n, pvec, 8 - n); 345115717Smarkm msgbuf[7] = n; 34616Salm for (n = 0; n < 8; n++) 347115717Smarkm msgbuf[n] ^= ivec[n]; 348115717Smarkm DES_XFORM((DES_cblock *)msgbuf); 349115717Smarkm return WRITE(msgbuf, 8, fp); 35016Salm} 35116Salm 35216Salm/* 35316Salm * This decrypts using the Cipher Block Chaining mode of DES 35490109Simp * msgbuf I/O buffer 35590109Simp * fp input file descriptor 35616Salm */ 3571057Salmint 358101093Smarkmcbc_decode(unsigned char *msgbuf, FILE *fp) 35916Salm{ 360115717Smarkm DES_cblock tbuf; /* temp buffer for initialization vector */ 36181220Smike int n; /* number of bytes actually read */ 36281220Smike int c; /* used to test for EOF */ 36316Salm int inverse = 1; /* 0 to encrypt, 1 to decrypt */ 36416Salm 365115717Smarkm if ((n = READ(msgbuf, 8, fp)) == 8) { 36616Salm /* 36716Salm * do the transformation 36816Salm */ 369115717Smarkm MEMCPY(tbuf, msgbuf, 8); 370115717Smarkm DES_XFORM((DES_cblock *)msgbuf); 37116Salm for (c = 0; c < 8; c++) 372115717Smarkm msgbuf[c] ^= ivec[c]; 373115717Smarkm MEMCPY(ivec, tbuf, 8); 37416Salm /* 37516Salm * if the last one, handle it specially 37616Salm */ 37716Salm if ((c = fgetc(fp)) == EOF) { 378115717Smarkm n = msgbuf[7]; 37916Salm if (n < 0 || n > 7) { 3801057Salm des_error("decryption failed (block corrupted)"); 38116Salm return EOF; 38216Salm } 38316Salm } else 38416Salm (void)ungetc(c, fp); 38516Salm return n; 38616Salm } 38716Salm if (n > 0) 3881057Salm des_error("decryption failed (incomplete block)"); 38916Salm else if (n < 0) 3901057Salm des_error("cannot read file"); 39116Salm return EOF; 39216Salm} 39316Salm#endif /* DES */ 394