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/* NOCW */
/*
Please read the README file for condition of use, before
using this software.
Maurice Gittens <mgittens@gits.nl> January 1997
*/
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <openssl/evp.h>
#define STDIN 0
#define STDOUT 1
#define BUFLEN 512
static const char *usage = "Usage: example4 [-d]\n";
void do_encode(void);
void do_decode(void);
int main(int argc, char *argv[])
{
if ((argc == 1))
{
do_encode();
}
else if ((argc == 2) && !strcmp(argv[1],"-d"))
{
do_decode();
}
else
{
fprintf(stderr,"%s", usage);
exit(1);
}
return 0;
}
void do_encode()
{
char buf[BUFLEN];
char ebuf[BUFLEN+24];
unsigned int ebuflen;
EVP_ENCODE_CTX ectx;
EVP_EncodeInit(&ectx);
while(1)
{
int readlen = read(STDIN, buf, sizeof(buf));
if (readlen <= 0)
{
if (!readlen)
break;
else
{
perror("read");
exit(1);
}
}
EVP_EncodeUpdate(&ectx, ebuf, &ebuflen, buf, readlen);
write(STDOUT, ebuf, ebuflen);
}
EVP_EncodeFinal(&ectx, ebuf, &ebuflen);
write(STDOUT, ebuf, ebuflen);
}
void do_decode()
{
char buf[BUFLEN];
char ebuf[BUFLEN+24];
unsigned int ebuflen;
EVP_ENCODE_CTX ectx;
EVP_DecodeInit(&ectx);
while(1)
{
int readlen = read(STDIN, buf, sizeof(buf));
int rc;
if (readlen <= 0)
{
if (!readlen)
break;
else
{
perror("read");
exit(1);
}
}
rc = EVP_DecodeUpdate(&ectx, ebuf, &ebuflen, buf, readlen);
if (rc <= 0)
{
if (!rc)
{
write(STDOUT, ebuf, ebuflen);
break;
}
fprintf(stderr, "Error: decoding message\n");
return;
}
write(STDOUT, ebuf, ebuflen);
}
EVP_DecodeFinal(&ectx, ebuf, &ebuflen);
write(STDOUT, ebuf, ebuflen);
}
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