Re: OpenSSL breaks factor(6)

On Sat, Dec 28, 2019 at 11:17:31PM -0800, Steve Kargl wrote:
> On Sun, Dec 29, 2019 at 01:34:28AM -0500, Garance A Drosehn wrote:
> > On 29 Dec 2019, at 0:10, Steve Kargl wrote:
> > 
> > > On Sat, Dec 28, 2019 at 10:46:52PM -0500, Garance A Drosehn wrote:
> > >>
> > >> What if the user wants to factor a hexadecimal value which does not
> > >> happen to include [a...f]?
> > >>
> > >> How about recognizing a prefix of '0x' as a way to indicate the value
> > >> is hexadecimal?

Here you go.  '0x' support is undocumented.

Index: usr.bin/factor/factor.6
===================================================================
--- usr.bin/factor/factor.6	(revision 355983)
+++ usr.bin/factor/factor.6	(working copy)
_at__at_ -36,7 +36,7 _at__at_
 .\"
 .\"   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
_at__at_ -67,11 +67,20 _at__at_
 .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
_at__at_ -89,7 +98,7 _at__at_
 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)
_at__at_ -71,6 +71,7 _at__at_
 #include <errno.h>
 #include <inttypes.h>
 #include <limits.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
_at__at_ -104,6 +105,7 _at__at_
 
 #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 */
_at__at_ -148,21 +150,37 _at__at_
 			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);
+			if (*p == '0') {
+				p++;
+				if (*p == 'x' || *p == 'X')
+					ch = BN_hex2bn(&val, ++p);
+			} else {
+				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]);
+			if (*p == '0') {
+				p++;
+				if (*p == 'x' || *p == 'X')
+					ch = BN_hex2bn(&val, ++p);
+			} else {
+				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);
_at__at_ -346,7 +364,7 _at__at_
 
 	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
_at__at_ -356,7 +374,7 _at__at_
 
 	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
_at__at_ -370,3 +388,20 _at__at_
 }
 
 #endif
+
+/*
+ * Check if the string contains one of 'abcdef' from the set of 
+ * hexadecimal digits.
+ */
+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)
_at__at_ -55,7 +55,7 _at__at_
  *	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