1 /* pwgen.c - A password generator.
2 *
3 * Copyright 2020 Moritz R�hrich <moritz@ildefons.de>
4
5 USE_PWGEN(NEWTOY(pwgen, ">2r(remove):c(capitalize)n(numerals)y(symbols)s(secure)B(ambiguous)h(help)C1vA(no-capitalize)0(no-numerals)[-cA][-n0][-C1]", TOYFLAG_USR|TOYFLAG_BIN))
6
7 config PWGEN
8 bool "pwgen"
9 default y
10 help
11 usage: pwgen [-cAn0yrsBhC1v] [LENGTH] [COUNT]
12
13 Generate human-readable random passwords. When output is to tty produces
14 a screenfull to defeat shoulder surfing (pick one and clear the screen).
15
16 -c --capitalize Permit capital letters.
17 -A --no-capitalize Don't include capital letters.
18 -n --numerals Permit numbers.
19 -0 --no-numerals Don't include numbers.
20 -y --symbols Permit special characters ($#%...).
21 -r <chars> --remove=<chars> Don't include the given characters.
22 -s --secure Generate more random passwords.
23 -B --ambiguous Avoid ambiguous characters (e.g. 0, O).
24 -h --help Print this help message.
25 -C Print the output in columns.
26 -1 Print the output one line each.
27 -v Don't include vowels.
28 */
29
30 #define FOR_pwgen
31 #include "toys.h"
32
GLOBALS(char * r;)33 GLOBALS(
34 char *r;
35 )
36
37 void pwgen_main(void)
38 {
39 int length = 8, count, ii, jj, c, rand = 0, x = 0;
40 unsigned xx = 80, yy = 24;
41 char randbuf[16];
42
43 if (isatty(1)) terminal_size(&xx, &yy);
44 else toys.optflags |= FLAG_1;
45
46 if (toys.optc && (length = atolx(*toys.optargs))>sizeof(toybuf))
47 error_exit("bad length");
48 if (toys.optc>1) count = atolx(toys.optargs[1]);
49 else count = FLAG(1) ? 1 : (xx/(length+1))*(yy-1);
50
51 for (jj = 0; jj<count; jj++) {
52 for (ii = 0; ii<length;) {
53 // Don't fetch more random than necessary, give each byte 2 tries to fit
54 if (!rand) xgetrandom(randbuf, rand = sizeof(randbuf), 0);
55 c = 33+randbuf[--rand]%93; // remainder 69 makes >102 less likely
56 if (FLAG(s)) randbuf[rand] = 0;
57
58 if (c>='A' && c<='Z') {
59 if (FLAG(A)) continue;
60 // take out half the capital letters to be more human readable
61 else c |= (0x80&randbuf[rand])>>2;
62 }
63 if (FLAG(0) && c>='0' && c<='9') continue;
64 if (FLAG(B) && strchr("0O1lI'`.,", c)) continue;
65 if (FLAG(v) && strchr("aeiou", tolower(c))) continue;
66 if (!FLAG(y) || (0x80&randbuf[rand]))
67 if (c<'0' || (c>'9' && c<'A') || (c>'Z' && c<'a') || c>'z') continue;
68 if (TT.r && strchr(TT.r, c)) continue;
69
70 toybuf[ii++] = c;
71 }
72 if (FLAG(1) || (x += length+1)+length>=xx) x = 0;
73 xprintf("%.*s%c", length, toybuf, x ? ' ' : '\n');
74 }
75 if (x) xputc('\n');
76 }
77