libbb: shrink obscure()

function                                             old     new   delta
string_checker_helper                                 59      45     -14
string_checker                                       116      98     -18
obscure                                              367     204    -163
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-195)           Total: -195 bytes

Signed-off-by: Bob Dunlop <bob.dunlop@xyzzy.org.uk>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Bob Dunlop 2010-08-17 16:01:16 +02:00 committed by Denys Vlasenko
parent cda815996b
commit d71c770f05

View File

@ -45,53 +45,59 @@ static int string_checker_helper(const char *p1, const char *p2) __attribute__ (
static int string_checker_helper(const char *p1, const char *p2)
{
/* as-is or capitalized */
if (strcasecmp(p1, p2) == 0
/* as sub-string */
|| strcasestr(p2, p1) != NULL
if (strcasestr(p2, p1) != NULL
/* invert in case haystack is shorter than needle */
|| strcasestr(p1, p2) != NULL)
|| strcasestr(p1, p2) != NULL
/* as-is or capitalized */
/* || strcasecmp(p1, p2) == 0 - 1st strcasestr should catch this too */
) {
return 1;
}
return 0;
}
static int string_checker(const char *p1, const char *p2)
{
int size;
int size, i;
/* check string */
int ret = string_checker_helper(p1, p2);
/* Make our own copy */
/* make our own copy */
char *p = xstrdup(p1);
/* reverse string */
size = strlen(p);
while (size--) {
*p = p1[size];
p++;
/* reverse string */
i = size = strlen(p1);
while (--i >= 0) {
*p++ = p1[i];
}
/* restore pointer */
p -= strlen(p1);
p -= size; /* restore pointer */
/* check reversed string */
ret |= string_checker_helper(p, p2);
/* clean up */
memset(p, 0, strlen(p1));
memset(p, 0, size);
free(p);
return ret;
}
#define CATEGORIES 4
#define LOWERCASE 1
#define UPPERCASE 2
#define NUMBERS 4
#define SPECIAL 8
#define LAST_CAT 8
static const char *obscure_msg(const char *old_p, const char *new_p, const struct passwd *pw)
{
int i;
int c;
int length;
int mixed = 0;
/* Add 2 for each type of characters to the minlen of password */
int size = CONFIG_PASSWORD_MINLEN + 8;
unsigned length;
unsigned size;
unsigned mixed;
unsigned c;
unsigned i;
const char *p;
char *hostname;
@ -104,7 +110,7 @@ static const char *obscure_msg(const char *old_p, const char *new_p, const struc
return "similar to username";
}
/* no gecos as-is, as sub-string, reversed, capitalized, doubled */
if (*pw->pw_gecos && string_checker(new_p, pw->pw_gecos)) {
if (pw->pw_gecos[0] && string_checker(new_p, pw->pw_gecos)) {
return "similar to gecos";
}
/* hostname as-is, as sub-string, reversed, capitalized, doubled */
@ -115,6 +121,7 @@ static const char *obscure_msg(const char *old_p, const char *new_p, const struc
return "similar to hostname";
/* Should / Must contain a mix of: */
mixed = 0;
for (i = 0; i < length; i++) {
if (islower(new_p[i])) { /* a-z */
mixed |= LOWERCASE;
@ -125,7 +132,7 @@ static const char *obscure_msg(const char *old_p, const char *new_p, const struc
} else { /* special characters */
mixed |= SPECIAL;
}
/* More than 50% similar characters ? */
/* Count i'th char */
c = 0;
p = new_p;
while (1) {
@ -134,26 +141,31 @@ static const char *obscure_msg(const char *old_p, const char *new_p, const struc
break;
}
c++;
if (!++p) {
break; /* move past the matched char if possible */
p++;
if (!*p) {
break;
}
}
if (c >= (length / 2)) {
/* More than 50% similar characters ? */
if (c*2 >= length) {
return "too many similar characters";
}
}
for (i=0; i<4; i++)
if (mixed & (1<<i)) size -= 2;
size = CONFIG_PASSWORD_MINLEN + 2*CATEGORIES;
for (i = 0; i <= LAST_CAT; i <<= 1)
if (mixed & i)
size -= 2;
if (length < size)
return "too weak";
if (old_p && old_p[0] != '\0') {
if (old_p && old_p[0]) {
/* check vs. old password */
if (string_checker(new_p, old_p)) {
return "similar to old password";
}
}
return NULL;
}