| /* 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 */ |
| } |
