ash: fix very weak $RANDOM generator; and move even more things
out of data/bss text data bss dec hex filename 807935 611 6884 815430 c7146 busybox_old 808035 611 6868 815514 c719a busybox_unstripped
This commit is contained in:
Denis Vlasenko
parent
843cbd54d1
commit
448d30ee17
116
shell/ash.c
116
shell/ash.c
@ -201,6 +201,14 @@ struct globals_misc {
|
||||
/* indicates specified signal received */
|
||||
char gotsig[NSIG - 1];
|
||||
char *trap[NSIG];
|
||||
|
||||
/* Rarely referenced stuff */
|
||||
#if ENABLE_ASH_RANDOM_SUPPORT
|
||||
int32_t random_galois_LFSR; /* Galois LFSR (fast but weak) */
|
||||
uint32_t random_LCG; /* LCG1 (fast but weak) */
|
||||
#endif
|
||||
pid_t backgndpid; /* pid of last background process */
|
||||
smallint job_warning; /* user was warned about stopped jobs (can be 2, 1 or 0). */
|
||||
};
|
||||
extern struct globals_misc *const ash_ptr_to_globals_misc;
|
||||
#define G_misc (*ash_ptr_to_globals_misc)
|
||||
@ -216,12 +224,16 @@ extern struct globals_misc *const ash_ptr_to_globals_misc;
|
||||
#define intpending (G_misc.intpending )
|
||||
//#define exsig (G_misc.exsig )
|
||||
#define pendingsig (G_misc.pendingsig )
|
||||
#define isloginsh (G_misc.isloginsh)
|
||||
#define nullstr (G_misc.nullstr )
|
||||
#define optlist (G_misc.optlist )
|
||||
#define sigmode (G_misc.sigmode )
|
||||
#define gotsig (G_misc.gotsig )
|
||||
#define trap (G_misc.trap )
|
||||
#define isloginsh (G_misc.isloginsh )
|
||||
#define nullstr (G_misc.nullstr )
|
||||
#define optlist (G_misc.optlist )
|
||||
#define sigmode (G_misc.sigmode )
|
||||
#define gotsig (G_misc.gotsig )
|
||||
#define trap (G_misc.trap )
|
||||
#define random_galois_LFSR (G_misc.random_galois_LFSR)
|
||||
#define random_LCG (G_misc.random_LCG )
|
||||
#define backgndpid (G_misc.backgndpid )
|
||||
#define job_warning (G_misc.job_warning)
|
||||
#define INIT_G_misc() do { \
|
||||
(*(struct globals_misc**)&ash_ptr_to_globals_misc) = xzalloc(sizeof(G_misc)); \
|
||||
barrier(); \
|
||||
@ -1006,12 +1018,12 @@ struct parsefile {
|
||||
struct strpush basestrpush; /* so pushing one is fast */
|
||||
};
|
||||
|
||||
static struct parsefile basepf; /* top level input file */
|
||||
static struct parsefile basepf; /* top level input file */
|
||||
static struct parsefile *g_parsefile = &basepf; /* current input file */
|
||||
static int startlinno; /* line # where last token started */
|
||||
static char *commandname; /* currently executing command */
|
||||
static struct strlist *cmdenviron; /* environment for builtin command */
|
||||
static int exitstatus; /* exit status of last command */
|
||||
static uint8_t exitstatus; /* exit status of last command */
|
||||
|
||||
|
||||
/* ============ Message printing */
|
||||
@ -1605,29 +1617,6 @@ nextopt(const char *optstring)
|
||||
}
|
||||
|
||||
|
||||
/* ============ Math support definitions */
|
||||
|
||||
#if ENABLE_ASH_MATH_SUPPORT_64
|
||||
typedef int64_t arith_t;
|
||||
#define arith_t_type long long
|
||||
#else
|
||||
typedef long arith_t;
|
||||
#define arith_t_type long
|
||||
#endif
|
||||
|
||||
#if ENABLE_ASH_MATH_SUPPORT
|
||||
static arith_t dash_arith(const char *);
|
||||
static arith_t arith(const char *expr, int *perrcode);
|
||||
#endif
|
||||
|
||||
#if ENABLE_ASH_RANDOM_SUPPORT
|
||||
static unsigned long rseed;
|
||||
#ifndef DYNAMIC_VAR
|
||||
#define DYNAMIC_VAR
|
||||
#endif
|
||||
#endif
|
||||
|
||||
|
||||
/* ============ Shell variables */
|
||||
|
||||
/*
|
||||
@ -1694,7 +1683,7 @@ struct localvar {
|
||||
#define VNOFUNC 0x40 /* don't call the callback function */
|
||||
#define VNOSET 0x80 /* do not set variable - just readonly test */
|
||||
#define VNOSAVE 0x100 /* when text is on the heap before setvareq */
|
||||
#ifdef DYNAMIC_VAR
|
||||
#if ENABLE_ASH_RANDOM_SUPPORT
|
||||
# define VDYNAMIC 0x200 /* dynamic variable */
|
||||
#else
|
||||
# define VDYNAMIC 0
|
||||
@ -1966,7 +1955,7 @@ lookupvar(const char *name)
|
||||
|
||||
v = *findvar(hashvar(name), name);
|
||||
if (v) {
|
||||
#ifdef DYNAMIC_VAR
|
||||
#if ENABLE_ASH_RANDOM_SUPPORT
|
||||
/*
|
||||
* Dynamic variables are implemented roughly the same way they are
|
||||
* in bash. Namely, they're "special" so long as they aren't unset.
|
||||
@ -2127,7 +2116,7 @@ unsetvar(const char *s)
|
||||
retval = 1;
|
||||
if (flags & VREADONLY)
|
||||
goto out;
|
||||
#ifdef DYNAMIC_VAR
|
||||
#if ENABLE_ASH_RANDOM_SUPPORT
|
||||
vp->flags &= ~VDYNAMIC;
|
||||
#endif
|
||||
if (flags & VUNSET)
|
||||
@ -3243,9 +3232,6 @@ struct job {
|
||||
struct job *prev_job; /* previous job */
|
||||
};
|
||||
|
||||
static pid_t backgndpid; /* pid of last background process */
|
||||
static smallint job_warning; /* user was warned about stopped jobs (can be 2, 1 or 0). */
|
||||
|
||||
static struct job *makejob(/*union node *,*/ int);
|
||||
#if !JOBS
|
||||
#define forkshell(job, node, mode) forkshell(job, mode)
|
||||
@ -3257,7 +3243,7 @@ static int waitforjob(struct job *);
|
||||
enum { doing_jobctl = 0 };
|
||||
#define setjobctl(on) do {} while (0)
|
||||
#else
|
||||
static smallint doing_jobctl;
|
||||
static smallint doing_jobctl; //references:8
|
||||
static void setjobctl(int);
|
||||
#endif
|
||||
|
||||
@ -3356,17 +3342,17 @@ setsignal(int signo)
|
||||
|
||||
#if JOBS
|
||||
/* pgrp of shell on invocation */
|
||||
static int initialpgrp;
|
||||
static int ttyfd = -1;
|
||||
static int initialpgrp; //references:2
|
||||
static int ttyfd = -1; //5
|
||||
#endif
|
||||
/* array of jobs */
|
||||
static struct job *jobtab;
|
||||
static struct job *jobtab; //5
|
||||
/* size of array */
|
||||
static unsigned njobs;
|
||||
static unsigned njobs; //4
|
||||
/* current job */
|
||||
static struct job *curjob;
|
||||
static struct job *curjob; //lots
|
||||
/* number of presumed living untracked jobs */
|
||||
static int jobless;
|
||||
static int jobless; //4
|
||||
|
||||
static void
|
||||
set_curjob(struct job *jp, unsigned mode)
|
||||
@ -5041,6 +5027,19 @@ redirectsafe(union node *redir, int flags)
|
||||
* We have to deal with backquotes, shell variables, and file metacharacters.
|
||||
*/
|
||||
|
||||
#if ENABLE_ASH_MATH_SUPPORT_64
|
||||
typedef int64_t arith_t;
|
||||
#define arith_t_type long long
|
||||
#else
|
||||
typedef long arith_t;
|
||||
#define arith_t_type long
|
||||
#endif
|
||||
|
||||
#if ENABLE_ASH_MATH_SUPPORT
|
||||
static arith_t dash_arith(const char *);
|
||||
static arith_t arith(const char *expr, int *perrcode);
|
||||
#endif
|
||||
|
||||
/*
|
||||
* expandarg flags
|
||||
*/
|
||||
@ -5358,7 +5357,7 @@ struct backcmd { /* result of evalbackcmd */
|
||||
};
|
||||
|
||||
/* These forward decls are needed to use "eval" code for backticks handling: */
|
||||
static smalluint back_exitstatus; /* exit status of backquoted command */
|
||||
static uint8_t back_exitstatus; /* exit status of backquoted command */
|
||||
#define EV_EXIT 01 /* exit after evaluating tree */
|
||||
static void evaltree(union node *, int);
|
||||
|
||||
@ -9619,18 +9618,33 @@ setcmd(int argc ATTRIBUTE_UNUSED, char **argv ATTRIBUTE_UNUSED)
|
||||
static void
|
||||
change_random(const char *value)
|
||||
{
|
||||
/* Galois LFSR parameter */
|
||||
/* Taps at 32 31 29 1: */
|
||||
enum { MASK = 0x8000000b };
|
||||
/* Another example - taps at 32 31 30 10: */
|
||||
/* MASK = 0x00400007 */
|
||||
|
||||
if (value == NULL) {
|
||||
/* "get", generate */
|
||||
char buf[16];
|
||||
uint32_t t;
|
||||
|
||||
rseed = rseed * 1103515245 + 12345;
|
||||
sprintf(buf, "%d", (unsigned int)((rseed & 32767)));
|
||||
/* LCG has period of 2^32 and alternating lowest bit */
|
||||
random_LCG = 1664525 * random_LCG + 1013904223;
|
||||
/* Galois LFSR has period of 2^32-1 = 3 * 5 * 17 * 257 * 65537 */
|
||||
t = (random_galois_LFSR << 1);
|
||||
if (random_galois_LFSR < 0) /* if we just shifted 1 out of msb... */
|
||||
t ^= MASK;
|
||||
random_galois_LFSR = t;
|
||||
/* Both are weak, xoring them gives better randomness
|
||||
* and ~2^64 period. & 0x7fff is probably bash compat
|
||||
* for $RANDOM range. */
|
||||
t = (t ^ random_LCG) & 0x7fff;
|
||||
/* set without recursion */
|
||||
setvar(vrandom.text, buf, VNOFUNC);
|
||||
setvar(vrandom.text, utoa(t), VNOFUNC);
|
||||
vrandom.flags &= ~VNOFUNC;
|
||||
} else {
|
||||
/* set/reset */
|
||||
rseed = strtoul(value, (char **)NULL, 10);
|
||||
random_galois_LFSR = random_LCG = strtoul(value, (char **)NULL, 10);
|
||||
}
|
||||
}
|
||||
#endif
|
||||
@ -13417,7 +13431,7 @@ int ash_main(int argc ATTRIBUTE_UNUSED, char **argv)
|
||||
rootpid = getpid();
|
||||
|
||||
#if ENABLE_ASH_RANDOM_SUPPORT
|
||||
rseed = rootpid + time(NULL);
|
||||
random_galois_LFSR = random_LCG = rootpid + time(NULL);
|
||||
#endif
|
||||
init();
|
||||
setstackmark(&smark);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user