1/* NOCW */
2/*
3        Please read the README file for condition of use, before
4        using this software.
5
6        Maurice Gittens  <mgittens@gits.nl>   January 1997
7
8*/
9
10#include <stdio.h>
11#include <unistd.h>
12#include <fcntl.h>
13#include <sys/stat.h>
14#include <openssl/evp.h>
15
16#define STDIN     	0
17#define STDOUT    	1
18#define BUFLEN	  	512
19
20static const char *usage = "Usage: example4 [-d]\n";
21
22void do_encode(void);
23void do_decode(void);
24
25int main(int argc, char *argv[])
26{
27	if ((argc == 1))
28	{
29		do_encode();
30	}
31	else if ((argc == 2) && !strcmp(argv[1],"-d"))
32	{
33		do_decode();
34	}
35	else
36	{
37		fprintf(stderr,"%s", usage);
38		exit(1);
39	}
40
41	return 0;
42}
43
44void do_encode()
45{
46	char buf[BUFLEN];
47	char ebuf[BUFLEN+24];
48	unsigned int ebuflen;
49	EVP_ENCODE_CTX ectx;
50
51	EVP_EncodeInit(&ectx);
52
53	while(1)
54	{
55		int readlen = read(STDIN, buf, sizeof(buf));
56
57		if (readlen <= 0)
58		{
59			if (!readlen)
60			   break;
61			else
62			{
63				perror("read");
64				exit(1);
65			}
66		}
67
68		EVP_EncodeUpdate(&ectx, ebuf, &ebuflen, buf, readlen);
69
70		write(STDOUT, ebuf, ebuflen);
71	}
72
73        EVP_EncodeFinal(&ectx, ebuf, &ebuflen);
74
75	write(STDOUT, ebuf, ebuflen);
76}
77
78void do_decode()
79{
80 	char buf[BUFLEN];
81 	char ebuf[BUFLEN+24];
82	unsigned int ebuflen;
83	EVP_ENCODE_CTX ectx;
84
85	EVP_DecodeInit(&ectx);
86
87	while(1)
88	{
89		int readlen = read(STDIN, buf, sizeof(buf));
90		int rc;
91
92		if (readlen <= 0)
93		{
94			if (!readlen)
95			   break;
96			else
97			{
98				perror("read");
99				exit(1);
100			}
101		}
102
103		rc = EVP_DecodeUpdate(&ectx, ebuf, &ebuflen, buf, readlen);
104		if (rc <= 0)
105		{
106			if (!rc)
107			{
108				write(STDOUT, ebuf, ebuflen);
109				break;
110			}
111
112			fprintf(stderr, "Error: decoding message\n");
113			return;
114		}
115
116		write(STDOUT, ebuf, ebuflen);
117	}
118
119        EVP_DecodeFinal(&ectx, ebuf, &ebuflen);
120
121	write(STDOUT, ebuf, ebuflen);
122}
123
124