From 8ee6e37953dcda74d4f360014f0b4531d741f495 Mon Sep 17 00:00:00 2001
From: Chris Oei <zlkm208-scryptgenpass@yahoo.com>
Date: Sun, 2 Sep 2012 19:46:30 -0700
Subject: [PATCH] Replace -t TIME param with -o mega-operations

---
 lib/genpass/genpass.c | 16 +++++-----------
 lib/genpass/genpass.h |  2 +-
 main.c                | 11 +++++------
 3 files changed, 11 insertions(+), 18 deletions(-)

diff --git a/lib/genpass/genpass.c b/lib/genpass/genpass.c
index 9fc8677..99fc50d 100644
--- a/lib/genpass/genpass.c
+++ b/lib/genpass/genpass.c
@@ -47,13 +47,13 @@
 
 #define ENCBLOCK 65536
 
-static int pickparams(size_t, double, double,
+static int pickparams(size_t, double, int,
     int *, uint32_t *, uint32_t *);
 static int checkparams(size_t, double, double, int, uint32_t, uint32_t);
 static int getsalt(uint8_t[32]);
 
 static int
-pickparams(size_t maxmem, double maxmemfrac, double maxtime,
+pickparams(size_t maxmem, double maxmemfrac, int megaops,
     int * logN, uint32_t * r, uint32_t * p)
 {
 	size_t memlimit;
@@ -66,13 +66,7 @@ pickparams(size_t maxmem, double maxmemfrac, double maxtime,
 	if (memtouse(maxmem, maxmemfrac, &memlimit))
 		return (1);
 
-	opps = 1; /* FIXIT: don't attempt to calculate CPU speed since
-	we want the same result on any computer. */
-	opslimit = opps * maxtime;
-
-	/* Allow a minimum of 2^15 salsa20/8 cores. */
-	if (opslimit < 32768)
-		opslimit = 32768;
+	opslimit = 1000000 * megaops;
 
 	/* Fix r = 8 for now. */
 	*r = 8;
@@ -199,7 +193,7 @@ err0:
 int
 genpass(uint8_t dk[64],
     const uint8_t * passwd, size_t passwdlen,
-    size_t maxmem, double maxmemfrac, double maxtime)
+    size_t maxmem, double maxmemfrac, int megaops)
 {
 	uint8_t salt[32];
 	uint8_t hbuf[32];
@@ -213,7 +207,7 @@ genpass(uint8_t dk[64],
 	int rc;
 
 	/* Pick values for N, r, p. */
-	if ((rc = pickparams(maxmem, maxmemfrac, maxtime,
+	if ((rc = pickparams(maxmem, maxmemfrac, megaops,
 	    &logN, &r, &p)) != 0)
 		return (rc);
 	N = (uint64_t)(1) << logN;
diff --git a/lib/genpass/genpass.h b/lib/genpass/genpass.h
index dfda41b..cd1b73e 100644
--- a/lib/genpass/genpass.h
+++ b/lib/genpass/genpass.h
@@ -74,6 +74,6 @@
 
 int genpass(uint8_t dk[64],
     const uint8_t * passwd, size_t passwdlen,
-    size_t maxmem, double maxmemfrac, double maxtime);
+    size_t maxmem, double maxmemfrac, int megaops);
 
 #endif /* !_GENPASS_H_ */
diff --git a/main.c b/main.c
index 57375ed..777a751 100644
--- a/main.c
+++ b/main.c
@@ -53,7 +53,7 @@ main(int argc, char *argv[])
 	int dec = 0;
 	size_t maxmem = 0;
 	double maxmemfrac = 0.5;
-	double maxtime = 300.0;
+	int megaops = 5;
 	char ch;
 	char * passwd;
 	int rc;
@@ -67,10 +67,9 @@ main(int argc, char *argv[])
 		usage();
 	maxmem = 0;
 	maxmemfrac = 0.125;
-	maxtime = 5.0;
 
 	/* Parse arguments. */
-	while ((ch = getopt(argc, argv, "hm:M:t:")) != -1) {
+	while ((ch = getopt(argc, argv, "hm:M:o:")) != -1) {
 		switch (ch) {
 		case 'M':
 			maxmem = strtoumax(optarg, NULL, 0);
@@ -78,8 +77,8 @@ main(int argc, char *argv[])
 		case 'm':
 			maxmemfrac = strtod(optarg, NULL);
 			break;
-		case 't':
-			maxtime = strtod(optarg, NULL);
+		case 'o':
+			megaops = atoi(optarg);
 			break;
 		default:
 			usage();
@@ -99,7 +98,7 @@ main(int argc, char *argv[])
 
 	uint8_t dk[64];
 	rc = genpass(dk, (uint8_t *)passwd,
-	    strlen(passwd), maxmem, maxmemfrac, maxtime);
+	    strlen(passwd), maxmem, maxmemfrac, megaops);
 
 	/* Zero and free the password. */
 	memset(passwd, 0, strlen(passwd));