encrypt - Online Linux Manual PageSection : 3
Updated : 2023-02-05
Source : Linux man-pages 6.03
NAMEencrypt, setkey, encrypt_r, setkey_r − encrypt 64-bit messages
LIBRARYEncryption and decryption library (libcrypto, −lcrypto)
SYNOPSIS#define _XOPEN_SOURCE /* See feature_test_macros(7) */
#include <unistd.h>[[deprecated]] void encrypt(char block[64], int edflag);#define _XOPEN_SOURCE /* See feature_test_macros(7) */
#include <stdlib.h>[[deprecated]] void setkey(const char *key);#define _GNU_SOURCE /* See feature_test_macros(7) */
#include <crypt.h>[[deprecated]] void setkey_r(const char *key, struct crypt_data *data);
[[deprecated]] void encrypt_r(char *block, int edflag,
struct crypt_data *data);
DESCRIPTIONThese functions encrypt and decrypt 64-bit messages. The setkey() function sets the key used by encrypt(). The key argument used here is an array of 64 bytes, each of which has numerical value 1 or 0. The bytes key[n] where n=8*i-1 are ignored, so that the effective key length is 56 bits. The encrypt() function modifies the passed buffer, encoding if edflag is 0, and decoding if 1 is being passed. Like the key argument, also block is a bit vector representation of the actual value that is encoded. The result is returned in that same vector. These two functions are not reentrant, that is, the key data is kept in static storage. The functions setkey_r() and encrypt_r() are the reentrant versions. They use the following structure to hold the key data: struct crypt_data {
char keysched[16 * 8];
char sb0[32768];
char sb1[32768];
char sb2[32768];
char sb3[32768];
char crypt_3_buf[14];
char current_salt[2];
long current_saltbits;
int direction;
int initialized;
};Before calling setkey_r() set data−>initialized to zero.
RETURN VALUEThese functions do not return any value.
ERRORSSet errno to zero before calling the above functions. On success, errno is unchanged. ENOSYS The function is not provided. (For example because of former USA export restrictions.)
VERSIONSBecause they employ the DES block cipher, which is no longer considered secure, encrypt(), encrypt_r(), setkey(), and setkey_r() were removed in glibc 2.28. Applications should switch to a modern cryptography library, such as libgcrypt.
ATTRIBUTESFor an explanation of the terms used in this section, see attributes(7). InterfaceAttributeValue encrypt(), setkey() Thread safetyMT-Unsafe race:crypt encrypt_r(), setkey_r() Thread safetyMT-Safe
STANDARDSencrypt(), setkey(): POSIX.1-2001, POSIX.1-2008, SUS, SVr4. The functions encrypt_r() and setkey_r() are GNU extensions.
NOTES
Availability in glibcSee crypt(3).
Features in glibcIn glibc 2.2, these functions use the DES algorithm.
EXAMPLES #define _XOPEN_SOURCE
#include <crypt.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
int
main(void)
{
char key[64];
char orig[9] = "eggplant";
char buf[64];
char txt[9];
for (size_t i = 0; i < 64; i++) {
key[i] = rand() & 1;
}
for (size_t i = 0; i < 8; i++) {
for (size_t j = 0; j < 8; j++) {
buf[i * 8 + j] = orig[i] >> j & 1;
}
setkey(key);
}
printf("Before encrypting: %s\n", orig);
encrypt(buf, 0);
for (size_t i = 0; i < 8; i++) {
for (size_t j = 0, txt[i] = '\0'; j < 8; j++) {
txt[i] |= buf[i * 8 + j] << j;
}
txt[8] = '\0';
}
printf("After encrypting: %s\n", txt);
encrypt(buf, 1);
for (size_t i = 0; i < 8; i++) {
for (size_t j = 0, txt[i] = '\0'; j < 8; j++) {
txt[i] |= buf[i * 8 + j] << j;
}
txt[8] = '\0';
}
printf("After decrypting: %s\n", txt);
exit(EXIT_SUCCESS);
}
SEE ALSOcbc_crypt(3), crypt(3), ecb_crypt(3) 0
Johanes Gumabo
Data Size : 18,283 byte
man-setkey_r.3Build : 2024-12-05, 20:55 :
Visitor Screen : x
Visitor Counter ( page / site ) : 3 / 202,690
Visitor ID : :
Visitor IP : 3.142.212.225 :
Visitor Provider : AMAZON-02 :
Provider Position ( lat x lon ) : 39.962500 x -83.006100 : x
Provider Accuracy Radius ( km ) : 1000 :
Provider City : Columbus :
Provider Province : Ohio , : ,
Provider Country : United States :
Provider Continent : North America :
Visitor Recorder : Version :
Visitor Recorder : Library :
Online Linux Manual Page : Version : Online Linux Manual Page - Fedora.40 - march=x86-64 - mtune=generic - 24.12.05
Online Linux Manual Page : Library : lib_c - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Online Linux Manual Page : Library : lib_m - 24.10.03 - march=x86-64 - mtune=generic - Fedora.40
Data Base : Version : Online Linux Manual Page Database - 24.04.13 - march=x86-64 - mtune=generic - fedora-38
Data Base : Library : lib_c - 23.02.07 - march=x86-64 - mtune=generic - fedora.36
Very long time ago, I have the best tutor, Wenzel Svojanovsky . If someone knows the email address of Wenzel Svojanovsky , please send an email to johanes_gumabo@yahoo.co.id .
If error, please print screen and send to johanes_gumabo@yahoo.co.id
Under development. Support me via PayPal.