--- /dev/null
+/* 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 */
+ }
+
projects / cassiopeia.git / blobdiff