xref: /aosp_15_r20/external/toybox/toys/other/pwgen.c (revision cf5a6c84e2b8763fc1a7db14496fd4742913b199)
1 /* pwgen.c - A password generator.
2  *
3  * Copyright 2020 Moritz R�hrich <[email protected]>
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 [-cAn0yrsBC1v] [-r CHARS] [LENGTH] [COUNT]
12 
13     Generate human-readable random passwords. Default output to tty fills screen
14     with passwords to defeat shoulder surfing (pick one and clear the screen).
15 
16     -0	No numbers (--no-numerals)
17     -1	Output one per line
18     -A	No capital letters (--no-capitalize)
19     -B	Avoid ambiguous characters like 0O and 1lI (--ambiguous)
20     -C	Output in columns
21     -c	Add capital letters (--capitalize)
22     -n	Add numbers (--numerals)
23     -r	Don't include the given CHARS (--remove)
24     -v	No vowels.
25     -y	Add punctuation (--symbols)
26 */
27 
28 #define FOR_pwgen
29 #include "toys.h"
30 
GLOBALS(char * r;)31 GLOBALS(
32   char *r;
33 )
34 
35 void pwgen_main(void)
36 {
37   int length = 8, count, ii, jj, c, rand = 0, x = 0;
38   unsigned xx = 80, yy = 24;
39   char randbuf[16];
40 
41   if (isatty(1)) terminal_size(&xx, &yy);
42   else toys.optflags |= FLAG_1;
43 
44   if (toys.optc && (length = atolx(*toys.optargs))>sizeof(toybuf))
45     error_exit("bad length");
46   if (toys.optc>1) count = atolx(toys.optargs[1]);
47   else count = FLAG(1) ? 1 : (xx/(length+1))*(yy-1);
48 
49   for (jj = 0; jj<count; jj++) {
50     for (ii = 0; ii<length;) {
51       // Don't fetch more random than necessary, give each byte 2 tries to fit
52       if (!rand) xgetrandom(randbuf, rand = sizeof(randbuf));
53       c = 33+randbuf[--rand]%94; // remainder 67 makes >102 less likely
54       randbuf[rand] = 0;
55 
56       if (c>='A' && c<='Z') {
57         if (FLAG(A)) continue;
58         // take out half the capital letters to be more human readable
59         else c |= (0x80&randbuf[rand])>>2;
60       }
61       if (FLAG(0) && c>='0' && c<='9') continue;
62       if (FLAG(B) && strchr("0O1lI8B5S2ZD'`.,", c)) continue;
63       if (FLAG(v) && strchr("aeiou", tolower(c))) continue;
64       if (!FLAG(y) || (0x80&randbuf[rand]))
65         if (c<'0' || (c>'9' && c<'A') || (c>'Z' && c<'a') || c>'z') continue;
66       if (TT.r && strchr(TT.r, c)) continue;
67 
68       toybuf[ii++] = c;
69     }
70     if (FLAG(1) || (x += length+1)+length>=xx) x = 0;
71     xprintf("%.*s%c", length, toybuf, x ? ' ' : '\n');
72   }
73   if (x) xputc('\n');
74 }
75