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Diffstat (limited to 'openssl/crypto/des/enc_read.c')
| -rw-r--r-- | openssl/crypto/des/enc_read.c | 240 |
1 files changed, 240 insertions, 0 deletions
diff --git a/openssl/crypto/des/enc_read.c b/openssl/crypto/des/enc_read.c new file mode 100644 index 00000000..edb6620d --- /dev/null +++ b/openssl/crypto/des/enc_read.c @@ -0,0 +1,240 @@ +/* crypto/des/enc_read.c */ +/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) + * All rights reserved. + * + * This package is an SSL implementation written + * by Eric Young (eay@cryptsoft.com). + * The implementation was written so as to conform with Netscapes SSL. + * + * This library is free for commercial and non-commercial use as long as + * the following conditions are aheared to. The following conditions + * apply to all code found in this distribution, be it the RC4, RSA, + * lhash, DES, etc., code; not just the SSL code. The SSL documentation + * included with this distribution is covered by the same copyright terms + * except that the holder is Tim Hudson (tjh@cryptsoft.com). + * + * Copyright remains Eric Young's, and as such any Copyright notices in + * the code are not to be removed. + * If this package is used in a product, Eric Young should be given attribution + * as the author of the parts of the library used. + * This can be in the form of a textual message at program startup or + * in documentation (online or textual) provided with the package. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * "This product includes cryptographic software written by + * Eric Young (eay@cryptsoft.com)" + * The word 'cryptographic' can be left out if the rouines from the library + * being used are not cryptographic related :-). + * 4. If you include any Windows specific code (or a derivative thereof) from + * the apps directory (application code) you must include an acknowledgement: + * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" + * + * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * The licence and distribution terms for any publically available version or + * derivative of this code cannot be changed. i.e. this code cannot simply be + * copied and put under another distribution licence + * [including the GNU Public Licence.] + */ + +#include <stdio.h> +#include <errno.h> +#include "cryptlib.h" +#include "des_locl.h" + +/* This has some uglies in it but it works - even over sockets. */ +/*extern int errno;*/ +OPENSSL_IMPLEMENT_GLOBAL(int,DES_rw_mode,DES_PCBC_MODE) + + +/* + * WARNINGS: + * + * - The data format used by DES_enc_write() and DES_enc_read() + * has a cryptographic weakness: When asked to write more + * than MAXWRITE bytes, DES_enc_write will split the data + * into several chunks that are all encrypted + * using the same IV. So don't use these functions unless you + * are sure you know what you do (in which case you might + * not want to use them anyway). + * + * - This code cannot handle non-blocking sockets. + * + * - This function uses an internal state and thus cannot be + * used on multiple files. + */ + + +int DES_enc_read(int fd, void *buf, int len, DES_key_schedule *sched, + DES_cblock *iv) + { +#if defined(OPENSSL_NO_POSIX_IO) + return(0); +#else + /* data to be unencrypted */ + int net_num=0; + static unsigned char *net=NULL; + /* extra unencrypted data + * for when a block of 100 comes in but is des_read one byte at + * a time. */ + static unsigned char *unnet=NULL; + static int unnet_start=0; + static int unnet_left=0; + static unsigned char *tmpbuf=NULL; + int i; + long num=0,rnum; + unsigned char *p; + + if (tmpbuf == NULL) + { + tmpbuf=OPENSSL_malloc(BSIZE); + if (tmpbuf == NULL) return(-1); + } + if (net == NULL) + { + net=OPENSSL_malloc(BSIZE); + if (net == NULL) return(-1); + } + if (unnet == NULL) + { + unnet=OPENSSL_malloc(BSIZE); + if (unnet == NULL) return(-1); + } + /* left over data from last decrypt */ + if (unnet_left != 0) + { + if (unnet_left < len) + { + /* we still still need more data but will return + * with the number of bytes we have - should always + * check the return value */ + memcpy(buf,&(unnet[unnet_start]), + unnet_left); + /* eay 26/08/92 I had the next 2 lines + * reversed :-( */ + i=unnet_left; + unnet_start=unnet_left=0; + } + else + { + memcpy(buf,&(unnet[unnet_start]),len); + unnet_start+=len; + unnet_left-=len; + i=len; + } + return(i); + } + + /* We need to get more data. */ + if (len > MAXWRITE) len=MAXWRITE; + + /* first - get the length */ + while (net_num < HDRSIZE) + { +#ifndef OPENSSL_SYS_WIN32 + i=read(fd,(void *)&(net[net_num]),HDRSIZE-net_num); +#else + i=_read(fd,(void *)&(net[net_num]),HDRSIZE-net_num); +#endif +#ifdef EINTR + if ((i == -1) && (errno == EINTR)) continue; +#endif + if (i <= 0) return(0); + net_num+=i; + } + + /* we now have at net_num bytes in net */ + p=net; + /* num=0; */ + n2l(p,num); + /* num should be rounded up to the next group of eight + * we make sure that we have read a multiple of 8 bytes from the net. + */ + if ((num > MAXWRITE) || (num < 0)) /* error */ + return(-1); + rnum=(num < 8)?8:((num+7)/8*8); + + net_num=0; + while (net_num < rnum) + { +#ifndef OPENSSL_SYS_WIN32 + i=read(fd,(void *)&(net[net_num]),rnum-net_num); +#else + i=_read(fd,(void *)&(net[net_num]),rnum-net_num); +#endif +#ifdef EINTR + if ((i == -1) && (errno == EINTR)) continue; +#endif + if (i <= 0) return(0); + net_num+=i; + } + + /* Check if there will be data left over. */ + if (len < num) + { + if (DES_rw_mode & DES_PCBC_MODE) + DES_pcbc_encrypt(net,unnet,num,sched,iv,DES_DECRYPT); + else + DES_cbc_encrypt(net,unnet,num,sched,iv,DES_DECRYPT); + memcpy(buf,unnet,len); + unnet_start=len; + unnet_left=num-len; + + /* The following line is done because we return num + * as the number of bytes read. */ + num=len; + } + else + { + /* >output is a multiple of 8 byes, if len < rnum + * >we must be careful. The user must be aware that this + * >routine will write more bytes than he asked for. + * >The length of the buffer must be correct. + * FIXED - Should be ok now 18-9-90 - eay */ + if (len < rnum) + { + + if (DES_rw_mode & DES_PCBC_MODE) + DES_pcbc_encrypt(net,tmpbuf,num,sched,iv, + DES_DECRYPT); + else + DES_cbc_encrypt(net,tmpbuf,num,sched,iv, + DES_DECRYPT); + + /* eay 26/08/92 fix a bug that returned more + * bytes than you asked for (returned len bytes :-( */ + memcpy(buf,tmpbuf,num); + } + else + { + if (DES_rw_mode & DES_PCBC_MODE) + DES_pcbc_encrypt(net,buf,num,sched,iv, + DES_DECRYPT); + else + DES_cbc_encrypt(net,buf,num,sched,iv, + DES_DECRYPT); + } + } + return num; +#endif /* OPENSSL_NO_POSIX_IO */ + } + |