README.md

@@ -4,7 +4,7 @@ HTTP Hashcash implemented in Go.
 
 Explanation at https://therootcompany.com/blog/http-hashcash/
 
-Go API docs at https://pkg.go.dev/git.rootprojects.org/root/hashcash?tab=doc
+Go docs at https://godoc.org/git.rootprojects.org/root/hashcash
 
 # CLI Usage
 
@@ -21,7 +21,6 @@ Usage:
 	hashcash new [subject *] [expires in 5m] [difficulty 10]
 	hashcash parse <hashcash>
 	hashcash solve <hashcash>
-	hashcash hash <hashcash>
 	hashcash verify <hashcash> [subject *]
 ```
 

cmd/hashcash/hashcash.go

@@ -1,8 +1,6 @@
 package main
 
 import (
-	"crypto/sha256"
-	"encoding/hex"
 	"encoding/json"
 	"fmt"
 	"os"
@@ -14,18 +12,16 @@ import (
 
 func help() {
 	fmt.Println("Usage:")
-	fmt.Println("\thashcash new [subject *] [difficulty 10] [expires in 5m]")
+	fmt.Println("\thashcash new [subject *] [expires in 5m] [difficulty 10]")
 	fmt.Println("\thashcash parse <hashcash>")
 	fmt.Println("\thashcash solve <hashcash>")
-	fmt.Println("\thashcash hash <hashcash>")
 	fmt.Println("\thashcash verify <hashcash> [subject *]")
 }
 
 func main() {
 	args := os.Args[:]
-	nargs := len(args)
 
-	if nargs < 2 {
+	if len(args) < 2 {
 		help()
 		os.Exit(1)
 		return
@@ -34,30 +30,27 @@ func main() {
 	switch args[1] {
 	case "new":
 		var subject string
-		if nargs >= 3 {
+		if len(args) > 3 {
 			subject = args[2]
 		}
 
 		var difficulty int
-		if nargs >= 4 {
+		if len(args) > 4 {
 			var err error
 			difficulty, err = strconv.Atoi(args[3])
 			if nil != err {
 				help()
 				os.Exit(1)
-				return
 			}
 		}
 
 		var expIn time.Duration
-		if nargs >= 5 {
+		if len(args) > 5 {
 			var err error
 			expIn, err = time.ParseDuration(args[4])
 			if nil != err {
-				fmt.Println(err)
 				help()
 				os.Exit(1)
-				return
 			}
 		} else {
 			expIn = 5 * time.Minute
@@ -73,7 +66,7 @@ func main() {
 		return
 	case "parse":
 		var token string
-		if 3 != nargs {
+		if 3 != len(args) {
 			help()
 			os.Exit(1)
 			return
@@ -89,7 +82,7 @@ func main() {
 		return
 	case "solve":
 		var token string
-		if 3 != nargs {
+		if 3 != len(args) {
 			help()
 			os.Exit(1)
 			return
@@ -110,20 +103,9 @@ func main() {
 
 		fmt.Println(h.String())
 		return
-	case "hash":
-		var token string
-		if 3 != nargs {
-			help()
-			os.Exit(1)
-			return
-		}
-		token = args[2]
-		hash := sha256.Sum256([]byte(token))
-		fmt.Println(hex.EncodeToString(hash[:]))
-		return
 	case "verify":
 		var token string
-		if nargs < 3 {
+		if len(args) < 3 {
 			help()
 			os.Exit(1)
 			return
@@ -136,7 +118,7 @@ func main() {
 		}
 
 		subject := "*"
-		if nargs >= 4 {
+		if len(args) > 3 {
 			subject = args[3]
 		}
 

hashcash.go

@@ -216,10 +216,6 @@ func (h *Hashcash) Verify(subject string) error {
 }
 
 func verifyBits(hash []byte, bits, n int) bool {
-	if 0 == bits {
-		return true
-	}
-
 	for i := 0; i < n; i++ {
 		if bits > 8 {
 			bits -= 8
@@ -231,12 +227,15 @@ func verifyBits(hash []byte, bits, n int) bool {
 
 		// (bits % 8) == bits
 		pad := 8 - bits
-		if 0 == hash[i]>>pad {
-			return true
-		}
+		if 0 != hash[i]>>pad {
+			return false
 		}
 
-	return false
+		return true
+	}
+
+	// 0 == bits
+	return true
 }
 
 // Solve will search for a solution, returning an error if the difficulty is