900406c35
Denis Vlasenko
2006-12-12
Subject
passwd: shrink by ~10 bytes, use PRNG instead of usleep.
Binary
No binary (build failed)
Architecture & Compiler Flags
—
Build Log
(log yok)
Commit Diff GitHub →
loginutils/passwd.c+10 -17
| @@ -5,7 +5,6 @@ | |
| #include "busybox.h" | |
| #include <syslog.h> | |
| - | #include <sys/times.h> /* times() */ |
| static void nuke_str(char *str) | |
| @@ -16,7 +15,8 @@ static void nuke_str(char *str) | |
| static int i64c(int i) | |
| { | |
| - | if (i <= 0) |
| + | i &= 0x3f; |
| + | if (i == 0) |
| return '.'; | |
| if (i == 1) | |
| return '/'; | |
| @@ -30,23 +30,16 @@ static int i64c(int i) | |
| static void crypt_make_salt(char *p, int cnt) | |
| { | |
| - | #if !defined(__GLIBC__) |
| - | struct tms t; |
| - | #define TIMES times(&t) |
| - | #else |
| - | /* glibc allows for times(NULL) a-la time() */ |
| - | #define TIMES times(NULL) |
| - | #endif |
| - | unsigned long x = x; /* it's pointless to initialize it anyway :) */ |
| + | unsigned x = x; /* it's pointless to initialize it anyway :) */ |
| - | x += getpid(); |
| + | x += getpid() + time(NULL) + clock(); |
| do { | |
| - | /* clock() and times() variability is different between systems */ |
| - | /* hopefully at least one is good enough */ |
| - | x += time(NULL) + clock() + TIMES; |
| - | *p++ = i64c(((x >> 18) ^ (x >> 6)) & 0x3f); |
| - | *p++ = i64c(((x >> 12) ^ x) & 0x3f); |
| - | usleep(100); /* or else time() etc won't change */ |
| + | /* x = (x*1664525 + 1013904223) mod 2^32 generator is lame |
| + | * (low-order bit is not "random", etc...), |
| + | * but for our purposes it is good enough */ |
| + | x = x*1664525 + 1013904223; |
| + | *p++ = i64c(x >> 16); |
| + | *p++ = i64c(x >> 22); |
| } while (--cnt); | |
| *p = '\0'; | |
| } | |