1 /* crypto/des/enc_writ.c */ 2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59 #include <errno.h> 60 #include <time.h> 61 #include <stdio.h> 62 #include "des_locl.h" 63 64 /* 65 * WARNINGS: 66 * 67 * - The data format used by des_enc_write() and des_enc_read() 68 * has a cryptographic weakness: When asked to write more 69 * than MAXWRITE bytes, des_enc_write will split the data 70 * into several chunks that are all encrypted 71 * using the same IV. So don't use these functions unless you 72 * are sure you know what you do (in which case you might 73 * not want to use them anyway). 74 * 75 * - This code cannot handle non-blocking sockets. 76 */ 77 78 int des_enc_write(int fd, const void *_buf, int len, 79 des_key_schedule sched, des_cblock *iv) 80 { 81 #ifdef _LIBC 82 extern unsigned long time(); 83 extern int write(); 84 #endif 85 const unsigned char *buf=_buf; 86 long rnum; 87 int i,j,k,outnum; 88 static unsigned char *outbuf=NULL; 89 unsigned char shortbuf[8]; 90 unsigned char *p; 91 const unsigned char *cp; 92 static int start=1; 93 94 if (outbuf == NULL) 95 { 96 outbuf=OPENSSL_malloc(BSIZE+HDRSIZE); 97 if (outbuf == NULL) return(-1); 98 } 99 /* If we are sending less than 8 bytes, the same char will look 100 * the same if we don't pad it out with random bytes */ 101 if (start) 102 { 103 start=0; 104 } 105 106 /* lets recurse if we want to send the data in small chunks */ 107 if (len > MAXWRITE) 108 { 109 j=0; 110 for (i=0; i<len; i+=k) 111 { 112 k=des_enc_write(fd,&(buf[i]), 113 ((len-i) > MAXWRITE)?MAXWRITE:(len-i),sched,iv); 114 if (k < 0) 115 return(k); 116 else 117 j+=k; 118 } 119 return(j); 120 } 121 122 /* write length first */ 123 p=outbuf; 124 l2n(len,p); 125 126 /* pad short strings */ 127 if (len < 8) 128 { 129 cp=shortbuf; 130 memcpy(shortbuf,buf,len); 131 *(u_int32_t *)&shortbuf[0] = arc4random(); 132 *(u_int32_t *)&shortbuf[4] = arc4random(); 133 rnum=8; 134 } 135 else 136 { 137 cp=buf; 138 rnum=((len+7)/8*8); /* round up to nearest eight */ 139 } 140 141 if (des_rw_mode & DES_PCBC_MODE) 142 des_pcbc_encrypt(cp,&(outbuf[HDRSIZE]),(len<8)?8:len,sched,iv, 143 DES_ENCRYPT); 144 else 145 des_cbc_encrypt(cp,&(outbuf[HDRSIZE]),(len<8)?8:len,sched,iv, 146 DES_ENCRYPT); 147 148 /* output */ 149 outnum=rnum+HDRSIZE; 150 151 for (j=0; j<outnum; j+=i) 152 { 153 /* eay 26/08/92 I was not doing writing from where we 154 * got up to. */ 155 i=write(fd,(void *)&(outbuf[j]),outnum-j); 156 if (i == -1) 157 { 158 #ifdef EINTR 159 if (errno == EINTR) 160 i=0; 161 else 162 #endif 163 /* This is really a bad error - very bad 164 * It will stuff-up both ends. */ 165 return(-1); 166 } 167 } 168 169 return(len); 170 } 171