diff --git a/cmd/fmount/main.go b/cmd/fmount/main.go
index c9f1bca..921c878 100644
--- a/cmd/fmount/main.go
+++ b/cmd/fmount/main.go
@@ -2,7 +2,7 @@
 //
 // Usage:
 //
-//	fmount [-suzhv] [-T RAW|DD] [-D DIRECTORY] IMAGE
+//	fmount [-suzhv] [-H CRC32|MD5|SHA1|SHA256|SHA512] [-V SUM] [-T RAW|DD] [-D DIRECTORY] IMAGE
 //
 // The flags are:
 //
@@ -10,6 +10,10 @@
 //		The mount point directory.
 //	 -T type
 //	    The disk image type.
+//	 -H algorithm
+//	 	The hash algorithm to use.
+//	 -V sum
+//	 	The hash sum to verify.
 //	 -s
 //		System partition only.
 //	 -u
@@ -42,6 +46,8 @@ var Version string = "dev"
 func main() {
 	D := flag.String("D", "", "Mount point")
 	T := flag.String("T", "", "Image type")
+	H := flag.String("H", "", "Hash algorithm")
+	V := flag.String("V", "", "Hash sum")
 	s := flag.Bool("s", false, "System partition only")
 	u := flag.Bool("u", false, "Unmount image")
 	z := flag.Bool("z", false, "Unzip image")
@@ -58,7 +64,7 @@ func main() {
 	}
 
 	if *h || len(img) == 0 {
-		sys.Usage("fmount [-suzhv] [-T RAW|DD] [-D DIRECTORY] IMAGE")
+		sys.Usage("fmount [-suzhv] [-H CRC32|MD5|SHA1|SHA256|SHA512] [-V SUM] [-T RAW|DD] [-D DIRECTORY] IMAGE")
 	}
 
 	it, err := fmount.DetectType(img, *T)
@@ -73,6 +79,14 @@ func main() {
 		args = append(args, "-D", *D)
 	}
 
+	if len(*H) > 0 {
+		args = append(args, "-H", *H)
+	}
+
+	if len(*V) > 0 {
+		args = append(args, "-V", *V)
+	}
+
 	if *s {
 		args = append(args, "-s")
 	}
diff --git a/docs/fmount.dd.md b/docs/fmount.dd.md
index e3459a7..e53497e 100644
--- a/docs/fmount.dd.md
+++ b/docs/fmount.dd.md
@@ -2,12 +2,14 @@
 Mount forensic raw or dd disk images for read-only processing.
 
 ```sh
-$ fmount.dd [-fsuzhv] [-D DIRECTORY] IMAGE
+$ fmount.dd [-fsuzhv] [-H CRC32|MD5|SHA1|SHA256|SHA512] [-V SUM] [-D DIRECTORY] IMAGE
 ```
 
 Available options:
 
 - `-D` Mount point
+- `-H` Hash algorithm
+- `-V` Verify hash sum
 - `-f` Force type
 - `-s` System partition only
 - `-u` Unmount image
diff --git a/docs/fmount.md b/docs/fmount.md
index ed14fa4..e6fc52d 100644
--- a/docs/fmount.md
+++ b/docs/fmount.md
@@ -2,13 +2,15 @@
 Mount forensic disk images for read-only processing.
 
 ```sh
-$ fmount [-suzhv] [-T RAW|DD] [-D DIRECTORY] IMAGE
+$ fmount [-suzhv] [-H CRC32|MD5|SHA1|SHA256|SHA512] [-V SUM] [-T RAW|DD] [-D DIRECTORY] IMAGE
 ```
 
 Available options:
 
 - `-D` Mount point
 - `-T` Image type
+- `-H` Hash algorithm
+- `-V` Verify hash sum
 - `-s` System partition only
 - `-u` Unmount image
 - `-z` Unzip image
diff --git a/pkg/ffind/ffind.go b/pkg/ffind/ffind.go
index 2a29c3f..a5c0b3a 100644
--- a/pkg/ffind/ffind.go
+++ b/pkg/ffind/ffind.go
@@ -3,29 +3,18 @@ package ffind
 
 import (
 	"archive/zip"
-	"crypto/md5"
-	"crypto/sha1"
-	"crypto/sha256"
-	"crypto/sha512"
 	"fmt"
-	"hash"
-	"hash/crc32"
 	"io"
 	"os"
-	"strings"
 	"sync"
 	"time"
 
+	"github.com/cuhsat/fact/internal/hash"
 	"github.com/cuhsat/fact/internal/sys"
 	"github.com/cuhsat/fact/pkg/windows"
 )
 
 const (
-	CRC32  = "crc32"
-	MD5    = "md5"
-	SHA1   = "sha1"
-	SHA256 = "sha256"
-	SHA512 = "sha512"
 	rLimit = 1024
 )
 
@@ -34,15 +23,15 @@ type ffind struct {
 
 	sysroot string
 	archive string
-	hash    string
+	algo    string
 	rp      bool
 	so      bool
 	uo      bool
 }
 
-func Find(sysroot, archive, hash string, rp, so, uo bool) (lines []string) {
+func Find(sysroot, archive, algo string, rp, so, uo bool) (lines []string) {
 	// Going into live mode
-	if len(sysroot)+len(archive)+len(hash) == 0 {
+	if len(sysroot)+len(archive)+len(algo) == 0 {
 		host, err := os.Hostname()
 
 		if err != nil {
@@ -51,13 +40,13 @@ func Find(sysroot, archive, hash string, rp, so, uo bool) (lines []string) {
 		}
 
 		archive = host + ".zip"
-		hash = SHA256
+		algo = hash.SHA256
 	}
 
 	ff := &ffind{
 		sysroot: sysroot,
 		archive: archive,
-		hash:    hash,
+		algo:    algo,
 		rp:      rp,
 		so:      so,
 		uo:      uo,
@@ -128,6 +117,7 @@ func (ff *ffind) zip(in, out chan string) {
 
 	defer a.Close()
 
+	// TODO: move to internal/zip
 	w := zip.NewWriter(a)
 
 	defer w.Close()
@@ -168,53 +158,21 @@ func (ff *ffind) log(in, out chan string) {
 	defer close(out)
 	defer ff.wg.Done()
 
-	var h hash.Hash
-
-	switch strings.ToLower(ff.hash) {
-	case CRC32:
-		h = crc32.NewIEEE()
-	case MD5:
-		h = md5.New()
-	case SHA1:
-		h = sha1.New()
-	case SHA256:
-		h = sha256.New()
-	case SHA512:
-		h = sha512.New()
-	default:
-		if len(ff.hash) > 0 {
-			sys.Error("hash not supported:", ff.hash)
-		}
-	}
-
-	if h == nil {
-		for artifact := range in {
-			out <- ff.path(artifact)
-		}
-
-		return
-	}
-
 	for artifact := range in {
-		h.Reset()
-
-		src, err := os.Open(artifact)
+		p := ff.path(artifact)
 
-		if err != nil {
-			sys.Error(err)
-			continue
-		}
-
-		_, err = io.Copy(h, src)
+		if len(ff.algo) > 0 {
+			s, err := hash.Sum(artifact, ff.algo)
 
-		src.Close()
+			if err != nil {
+				sys.Error(err)
+				continue
+			}
 
-		if err != nil {
-			sys.Error(err)
-			continue
+			out <- fmt.Sprintf("%x  %s", s, p)
+		} else {
+			out <- p
 		}
-
-		out <- fmt.Sprintf("%x %s", h.Sum(nil), ff.path(artifact))
 	}
 }
 
diff --git a/pkg/fmount/fmount.go b/pkg/fmount/fmount.go
index 0aa3776..b8a7058 100644
--- a/pkg/fmount/fmount.go
+++ b/pkg/fmount/fmount.go
@@ -3,11 +3,13 @@ package fmount
 
 import (
 	"errors"
+	"fmt"
 	"os"
 	"path"
 	"path/filepath"
 	"strings"
 
+	"github.com/cuhsat/fact/internal/hash"
 	"github.com/cuhsat/fact/internal/sys"
 	"github.com/cuhsat/fact/internal/zip"
 	"github.com/cuhsat/fact/pkg/fmount/dd"
@@ -55,6 +57,18 @@ func Extract(img string) (p string, err error) {
 	return
 }
 
+func Verify(img, algo, sum string) (ok bool, err error) {
+	b, err := hash.Sum(img, algo)
+
+	if err != nil {
+		return
+	}
+
+	ok = fmt.Sprintf("%x", b) == strings.ToLower(sum)
+
+	return
+}
+
 func Forward(name string, arg ...string) {
 	sys.ExitCall(name, arg...)
 }