summaryrefslogtreecommitdiff
path: root/main.c
blob: cb3b0e0ac08d5298c9fdefde0b22d2d9dc5e115b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
/*
  main.c - main program
  (c) 2004-2005 Zeljko Vrba <zvrba@globalnet.hr>

  Permission is hereby granted, free of charge, to any person obtaining
  a copy of this software and associated documentation files (the
  "Software"), to deal in the Software without restriction, including
  without limitation the rights to use, copy, modify, merge, publish,
  distribute, sublicense, and/or sell copies of the Software, and to
  permit persons to whom the Software is furnished to do so, subject to
  the following conditions:

  The above copyright notice and this permission notice shall be
  included in all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <math.h>
#include "secure_memory.h"
#include "secure_random.h"
#include "pwgen.h"
#include "exceptions.h"

static char rcsid[] = "$Id: main.c 1 2005-11-13 20:23:40Z zvrba $";

static struct exception_context exception_context;
struct exception_context *the_exception_context = &exception_context;

static void exit_cleanup(void)
{
	SRNG_destroy((struct SRNG_st*)G_secure_memory->random_state);
	secure_memory_destroy();
}

static void usage(const char *argv0)
{
	fprintf(stderr, "USAGE: %s <-p[e] | -A[adhsy] | -r | -s[e]> N\n", argv0);
	fprintf(stderr,
	    "\nPASSPHRASE of N words from Diceware dictionary\n"
		"  -p    generate passphrase\n"
		"  -pe   generate enhanced (with symbols) passphrase\n"
		"\nSKEY PASSWORD of N words from S/Key dictionary\n"
		"  -s    generate passphrase\n"
		"  -se   generate enhanced (with symbols) passphrase\n"
		"\nASCII RANDOM of N elements (at least one option MUST be present)\n"
		"  -A    Each letter adds the following random elements in output:\n"
	    "    a    alphanumeric characters\n"
		"    d    decimal digits\n"
		"    h    hexadecimal digits\n"
		"    s    special characters\n"
		"    y    3-4 letter syllables\n"
		"\nRAW RANDOM\n"
		"  -r    output BASE64 encoded string of N random BITS\n"
		"  -k    output koremutake encoding of N random BITS\n");
	exit(1);
}

static unsigned int get_allowed_characters(const char *p)
{
	unsigned int characters = 0;

	while(*p) {
		switch(*p) {
		case 'a':
			characters |= chr_alphanumeric;
			break;
		case 'd':
			characters |= chr_dec_digits;
			break;
		case 'h':
			characters |= chr_hex_digits;
			break;
		case 's':
			characters |= chr_special;
			break;
		case 'y':
			characters |= chr_syllables;
			break;
		default:
			return 0;
		}
		++p;
	}
		
	/* filter out some combinations for correct entropy estimation */
	if(characters & chr_alphanumeric)
		characters &= ~(chr_dec_digits | chr_hex_digits);
	if(characters & chr_hex_digits)
		characters &= ~chr_dec_digits;
	if((characters & chr_syllables)
	&& (characters & (chr_alphanumeric | chr_dec_digits | chr_hex_digits))) {
		characters &= ~(chr_alphanumeric | chr_dec_digits | chr_hex_digits);
		characters |= chr_dec_digits;
	}

	return characters;
}

int main(int argc, char **argv)
{
	const char *getDiceWd(unsigned int);
	const char *getSkeyWd(unsigned int);
	unsigned int n;
	unsigned int srng_state_len;
	float entropy;
	enum exception_code exception;
	int retval = 0;

	init_exception_context(&exception_context);

	if(argc != 3)
		usage(argv[0]);

	n = atoi(argv[2]);
	if(n < 1) {
		fprintf(stderr, "ERROR: N must be an integer > 0\n");
		usage(argv[0]);
	}

	srng_state_len = SRNG_init(NULL);
	if(srng_state_len > MAX_RANDOM_STATE_SIZE) {
		fprintf(stderr, 
				"FATAL: too small MAX_RANDOM_STATE_SIZE "
				"(must be at least %u)\n", srng_state_len);
		return 1;
	}

	Try {
		secure_memory_init();
		SRNG_init((struct SRNG_st*)G_secure_memory->random_state);
		
		if(atexit(exit_cleanup) < 0) {
			fprintf(stderr, "FATAL: can't register cleanup handlers: \n");
			perror("atexit");
			return 1;
		}

		if(!strcmp(argv[1], "-p"))
			entropy = pwgen_diceware(
					(struct SRNG_st*)G_secure_memory->random_state, n, 0,
					getDiceWd, 8192, G_secure_memory->random_numbers,
					G_secure_memory->passphrase);
		else if(!strcmp(argv[1], "-pe"))
			entropy = pwgen_diceware(
					(struct SRNG_st*)G_secure_memory->random_state, n, 1,
					getDiceWd, 8192, G_secure_memory->random_numbers,
					G_secure_memory->passphrase);
		else if(!strcmp(argv[1], "-r"))
			entropy = pwgen_raw(
					(struct SRNG_st*)G_secure_memory->random_state, n,
					G_secure_memory->random_numbers,
					G_secure_memory->passphrase);
		else if(!strcmp(argv[1], "-k"))
			entropy = pwgen_koremutake(
					(struct SRNG_st*)G_secure_memory->random_state, n,
					G_secure_memory->random_numbers,
					G_secure_memory->passphrase);
		else if(!strcmp(argv[1], "-s"))
			entropy = pwgen_diceware(
					(struct SRNG_st*)G_secure_memory->random_state, n, 0,
					getSkeyWd, 2048, G_secure_memory->random_numbers,
					G_secure_memory->passphrase);
		else if(!strcmp(argv[1], "-se"))
			entropy = pwgen_diceware(
					(struct SRNG_st*)G_secure_memory->random_state, n, 1,
					getSkeyWd, 2048, G_secure_memory->random_numbers,
					G_secure_memory->passphrase);
		else if(!strncmp(argv[1], "-A", 2)) {
			unsigned int characters = get_allowed_characters(argv[1]+2);
			
			if(!characters)
				usage(argv[0]);
			entropy = pwgen_ascii(
					(struct SRNG_st*)G_secure_memory->random_state, n,
					characters, G_secure_memory->random_numbers,
					G_secure_memory->passphrase);
		} else {
			usage(argv[0]);
		}
	} Catch(exception) {
		switch(exception) {
		case out_of_memory_exception:
			fprintf(stderr, "FATAL: out of memory.\n");
			retval = 1;
			break;
		case lib_crypto_exception:
			fprintf(stderr, "FATAL: crypto library error.\n");
			retval = 1;
			break;
		case system_call_failed_exception:
			fprintf(stderr, "FATAL: system call failed.\n");
			retval = 1;
			break;
		default:
			fprintf(stderr, "FATAL: unhandled exception %u.\n", exception);
			retval = 1;
		}
	}

	if(!retval) {
		printf("----------------\n");
		/*
		 * SECURITY NOTE
		 * I have no idea how printf(3) is implemented and it just MIGHT copy
		 * some sensitive data to its own stack.
		 */
		printf("%s ;ENTROPY=%.2f bits\n", G_secure_memory->passphrase,
				entropy);
		printf("----------------\n");
	}
	return retval;
}