Nintendo Switch system title batch decrypter

nx-decrypt.sh

#!/bin/bash

HACTOOL=./hactool/hactool
KEYFILE=nintendo-switch-keys.dat

decrypt-nca() {
    NCAFILE=$1
    TARGDIR=$2

    TITLEID=$($HACTOOL -k $KEYFILE -i $NCAFILE 2>/dev/null | grep Title\ ID\: | head -n 1 | sed 's/ //g' | cut -d ':' -f 2)
    CONTENTTYPE=$($HACTOOL -k $KEYFILE -i $NCAFILE 2>/dev/null | grep Content\ Type\: | sed 's/ //g' | cut -d ':' -f 2)

    if [ -z "$TITLEID" ]; then
        echo "Failed to decode NCA file: $NCAFILE"
        exit 1
    fi

    TARGETFILE=$TARGDIR/$TITLEID.nca

    if [ "$CONTENTTYPE" = 'Meta' ]; then
        TARGETFILE=$TARGDIR/$TITLEID.meta.nca
    fi

    $HACTOOL -k $KEYFILE --plaintext="$TARGETFILE" $NCAFILE 2>/dev/null > /dev/null
}

usage() {
    echo "Usage: $1 <encrypted system titles location> <decrypted output directory>"
    exit 1
}

SYSDIR=$1
TARGETDIR=$2

if [ -z "$SYSDIR" ]; then
    usage $0
    exit 1;
fi

if [ -z "$TARGETDIR" ]; then
    usage $0
    exit 1;
fi

NCAFILES=$(find "$SYSDIR" -type f)

mkdir -p "${TARGETDIR}"

for i in $NCAFILES; do
    echo "Decrypting ${i}";
    decrypt-nca "${i}" "${TARGETDIR}"
done