On Fri, Dec 27, 2019 at 09:15:33PM -0800, Steve Kargl wrote:
> On Fri, Dec 27, 2019 at 08:42:53PM -0800, Rodney W. Grimes wrote:
> > > On Fri, Dec 27, 2019 at 07:00:04PM -0800, Rodney W. Grimes wrote:
> > > > > On Fri, Dec 27, 2019 at 01:47:17PM -0800, Steve Kargl wrote:
> > > > >
> > > > > This patch now includes a fix for hexadecimal conversion. It
> > > > > simple scans the string for a hex digit in [a,...,f] and assumes
> > > > > that a hexadecimal string has been entered. A string that includes
> > > > > character from the decimal digits is assumed to by a decimal
> > > > > representation.
> > > >
> > > > It looks to me that the old code did the common method of
> > > > try to convert as decimal, if that fails, try it as hex,
> > > > if that fails report an error.
> > > >
> > > > Why is is that this common logic no longer works?
> > >
> > > AFAICT, BN_dec2bn and BN_hex2bn from OpenSSL scan from left
> > > to right, does a conversion with what is possible, and reports
> > > success. That is, for 1abc, BN_dec2bn can convert 1 to 1 and
> > > reports success. The local implementations of these functions,
> > > when OpenSSL is not used, does not do this partial conversion.
> >
> > I think I see now, the local implementaton checks for whole
> > string conversion with a test for newline or null as the last
> > byte converted by strtoul, the OpenSSL does not do this.
> >
>
> My patch fixes that. The manpage documents that '1abcp' should
> convert '1abc'. The 'p' simply terminates the conversion. The
> local implementations actually flags an error. I suspect the
> logic never worked as intended. The use of OpenSSL functions
> in factor(6) was introduced in r104722 by fanf@.
>
> > So why ever use the, um, IMHO broken for this application,
> > SSL versions of these functions? Or if we do need to use
> > them for some reason apply the whole string conversion
> > checks as wrappers around them?
>
> You'll need to ask fanf@, but I suspect the SSL version
> was introduced to allow the factoring of integers that
> exceed (uint64_t)(-1).
>
Updated patch with a svn log message.
* usr.bin/factor/factor.6:
. Document support for hexadecimal numbers.
. Document termination conditions for interactive input.
. Correct the maximum value for 'stop'.
* usr.bin/factor/factor.c:
. Include stdbool for bool type.
. New function, contains_hex_alpha_digits(), checks whether an string
of digits contains one of the alpha digits for hexadecimal representations
(ie., abcdef). This function determines if decimal or hexadecimal
conversion is required.
. In the WITHOUT_OPENSSL case, make BN_dec2bn() and BN_hex2bn() conform
to the documented termination conditions for parsing a string.
* usr.bin/primes/primes.c:
. Fix a comment, which has been wrong since 2014-09-27 (r272207).
Index: usr.bin/factor/factor.6
===================================================================
--- usr.bin/factor/factor.6 (revision 355983)
+++ usr.bin/factor/factor.6 (working copy)
@@ -36,7 +36,7 @@
.\"
.\" chongo <for a good prime call: 391581 * 2^216193 - 1> /\oo/\
.\"
-.Dd October 10, 2002
+.Dd December 27, 2019
.Dt FACTOR 6
.Os
.Sh NAME
@@ -67,11 +67,20 @@
.Nm
is invoked with no arguments,
.Nm
-reads numbers, one per line, from standard input, until end of file or error.
+reads numbers, one per line, from standard input until end of file or 0
+is entered or an error occurs.
Leading white-space and empty lines are ignored.
Numbers may be preceded by a single
.Ql + .
Numbers are terminated by a non-digit character (such as a newline).
+Numbers can be either decimal or hexadecimal strings.
+If the string contains only decimal digits, it is treated as a
+decimal representation for a number.
+A hexadecimal string should not contain a
+.Em 0x
+or
+.Em 0X
+prefix.
After a number is read, it is factored.
.Pp
The
@@ -89,7 +98,7 @@
value must not be greater than the maximum.
The default and maximum value of
.Ar stop
-is 3825123056546413050.
+is 18446744073709551615.
.Pp
When the
.Nm primes
Index: usr.bin/factor/factor.c
===================================================================
--- usr.bin/factor/factor.c (revision 355983)
+++ usr.bin/factor/factor.c (working copy)
@@ -71,6 +71,7 @@
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
+#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
@@ -104,6 +105,7 @@
#endif
+static bool contains_hex_alpha_digits(char *str);
static void BN_print_dec_fp(FILE *, const BIGNUM *);
static void pr_fact(BIGNUM *); /* print factors of a value */
@@ -148,21 +150,25 @@
for (p = buf; isblank(*p); ++p);
if (*p == '\n' || *p == '\0')
continue;
+ if (*p == '+') p++;
if (*p == '-')
errx(1, "negative numbers aren't permitted.");
- if (BN_dec2bn(&val, buf) == 0 &&
- BN_hex2bn(&val, buf) == 0)
- errx(1, "%s: illegal numeric format.", buf);
+ ch = contains_hex_alpha_digits(p) ?
+ BN_hex2bn(&val, p) : BN_dec2bn(&val, p);
+ if (ch == 0)
+ errx(1, "%s: illegal numeric format.", p);
pr_fact(val);
}
/* Factor the arguments. */
else
- for (; *argv != NULL; ++argv) {
- if (argv[0][0] == '-')
+ for (p = *argv; p != NULL; p = *++argv) {
+ if (*p == '+') p++;
+ if (*p == '-')
errx(1, "negative numbers aren't permitted.");
- if (BN_dec2bn(&val, argv[0]) == 0 &&
- BN_hex2bn(&val, argv[0]) == 0)
- errx(1, "%s: illegal numeric format.", argv[0]);
+ ch = contains_hex_alpha_digits(p) ?
+ BN_hex2bn(&val, p) : BN_dec2bn(&val, p);
+ if (ch == 0)
+ errx(1, "%s: illegal numeric format.", p);
pr_fact(val);
}
exit(0);
@@ -346,7 +352,7 @@
errno = 0;
**a = strtoul(str, &p, 10);
- return (errno == 0 && (*p == '\n' || *p == '\0'));
+ return (errno == 0 ? 1 : 0); /* OpenSSL returns 0 on error! */
}
static int
@@ -356,7 +362,7 @@
errno = 0;
**a = strtoul(str, &p, 16);
- return (errno == 0 && (*p == '\n' || *p == '\0'));
+ return (errno == 0 ? 1 : 0); /* OpenSSL returns 0 on error! */
}
static BN_ULONG
@@ -370,3 +376,17 @@
}
#endif
+
+/* Check if the string contains a hexadecimal digit. */
+static bool
+contains_hex_alpha_digits(char *str)
+{
+ char c, *p;
+
+ for (p = str; *p; p++) {
+ c = tolower(*p);
+ if (c >= 'a' && c <= 'f')
+ return true;
+ }
+ return false;
+}
Index: usr.bin/primes/primes.c
===================================================================
--- usr.bin/primes/primes.c (revision 355983)
+++ usr.bin/primes/primes.c (working copy)
@@ -55,7 +55,7 @@
* primes [-h] [start [stop]]
*
* Print primes >= start and < stop. If stop is omitted,
- * the value 4294967295 (2^32-1) is assumed. If start is
+ * the value 18446744073709551615 (2^64-1) is assumed. If start is
* omitted, start is read from standard input.
*
* validation check: there are 664579 primes between 0 and 10^7
--
Steve
_______________________________________________
freebsd-current@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/freebsd-current
To unsubscribe, send any mail to "freebsd-current-unsubscr...@freebsd.org"
