Add mkcert -CAROOT

Closes #26
Fixes #21

README.md

@@ -52,17 +52,17 @@ Warning: the `rootCA-key.pem` file that mkcert automatically generates gives com
 
 ### Changing the location of the CA files
 
-The CA certificate and its key are stored in an application data folder in the user home. You usually don't have to worry about it, as installation is automated, but if you need it it's printed in the first line of the mkcert output.
+The CA certificate and its key are stored in an application data folder in the user home. You usually don't have to worry about it, as installation is automated, but if you need it it's printed by `mkcert -CAROOT`.
 
-If you want to manage separate CAs, you can use the environment variable `CAROOT` to set the folder where mkcert will place and look for the local CA files.
+If you want to manage separate CAs, you can use the environment variable `$CAROOT` to set the folder where mkcert will place and look for the local CA files.
 
 ### Installing the CA on other systems
 
 Installing in the trust store does not require the CA key, so you can export just the CA certificate and use mkcert to install it in other machines.
 
-* Look for the `rootCA.pem` file in `CAROOT` or in the default folder (see above)
+* Look for the `rootCA.pem` file in `mkcert -CAROOT`
 * copy it to a different machine
-* set `CAROOT` to its directory
+* set `$CAROOT` to its directory
 * run `mkcert -install`
 
 Remember that mkcert is meant for development purposes, not production, so it should not be used on end users' machines, and that you should *not* export or share `rootCA-key.pem`.

main.go

@@ -9,6 +9,7 @@ import (
 	"crypto"
 	"crypto/x509"
 	"flag"
+	"fmt"
 	"log"
 	"net"
 	"os"
@@ -23,7 +24,15 @@ func main() {
 	log.SetFlags(0)
 	var installFlag = flag.Bool("install", false, "install the local root CA in the system trust store")
 	var uninstallFlag = flag.Bool("uninstall", false, "uninstall the local root CA from the system trust store")
+	var carootFlag = flag.Bool("CAROOT", false, "print the CAROOT path")
 	flag.Parse()
+	if *carootFlag {
+		if *installFlag || *uninstallFlag {
+			log.Fatalln("ERROR: you can't set -[un]install and -CAROOT at the same time")
+		}
+		fmt.Println(getCAROOT())
+		return
+	}
 	if *installFlag && *uninstallFlag {
 		log.Fatalln("ERROR: you can't set -install and -uninstall at the same time")
 	}
@@ -96,9 +105,10 @@ Usage:
 	Generate "_wildcard.example.com.pem" and "_wildcard.example.com-key.pem".
 
 	$ mkcert -uninstall
-	Unnstall the local CA (but do not delete it).
+	Uninstall the local CA (but do not delete it).
 
-Change the CA certificate and key storage location by setting $CAROOT.
+Change the CA certificate and key storage location by setting $CAROOT,
+print it with "mkcert -CAROOT".
 `)
 		return
 	}