From 09a3995d1305c4fc67df8375b4d95852f1a26316 Mon Sep 17 00:00:00 2001
From: Alexandr Krylovskiy <alexandr.krylovskiy@gmail.com>
Date: Sat, 30 Jul 2022 14:16:46 +0200
Subject: [PATCH] Error out if broker CA file is invalid

---
 README.md | 10 +++++-----
 main.go   | 36 ++++++++++++++++++++----------------
 2 files changed, 25 insertions(+), 21 deletions(-)

diff --git a/README.md b/README.md
index e0d49dd..6fca343 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ $ ./mqtt-benchmark -h
 Usage of ./mqtt-benchmark:
   -broker string
     	MQTT broker endpoint as scheme://host:port (default "tcp://localhost:1883")
-  -broker-cacert string
+  -broker-ca-cert string
     	Path to broker CA certificate in PEM format
   -client-cert string
     	Path to client certificate in PEM format
@@ -32,6 +32,8 @@ Usage of ./mqtt-benchmark:
     	Output format: text|json (default "text")
   -insecure
     	Skip TLS certificate verification
+  -message-interval int
+    	Time interval in seconds to publish message (default 1)
   -password string
     	MQTT client password (empty if auth disabled)
   -payload string
@@ -40,6 +42,8 @@ Usage of ./mqtt-benchmark:
     	QoS for published messages (default 1)
   -quiet
     	Suppress logs while running
+  -ramp-up-time int
+    	Time in seconds to generate clients by default will not wait between load request
   -size int
     	Size of the messages payload (bytes) (default 100)
   -topic string
@@ -48,10 +52,6 @@ Usage of ./mqtt-benchmark:
     	MQTT client username (empty if auth disabled)
   -wait int
     	QoS 1 wait timeout in milliseconds (default 60000)
-  -ramp-up-time int
-        Time in seconds to generate clients, (default 0) i.e by default will not wait between load request
-  -message-interval
-        Time interval in seconds to publish message (default 1)
 ```
 
 > NOTE: if `count=1` or `clients=1`, the sample standard deviation will be returned as `0` (convention due to the [lack of NaN support in JSON](https://tools.ietf.org/html/rfc4627#section-2.4))
diff --git a/main.go b/main.go
index a549bbf..6722fcc 100644
--- a/main.go
+++ b/main.go
@@ -75,7 +75,7 @@ func main() {
 		clientPrefix         = flag.String("client-prefix", "mqtt-benchmark", "MQTT client id prefix (suffixed with '-<client-num>'")
 		clientCert           = flag.String("client-cert", "", "Path to client certificate in PEM format")
 		clientKey            = flag.String("client-key", "", "Path to private clientKey in PEM format")
-    brokerCaCert         = flag.String("broker-cacert", "", "Path to broker CA certificate in PEM format")
+		brokerCaCert         = flag.String("broker-ca-cert", "", "Path to broker CA certificate in PEM format")
 		insecure             = flag.Bool("insecure", false, "Skip TLS certificate verification")
 		rampUpTimeInSec      = flag.Int("ramp-up-time", 0, "Time in seconds to generate clients by default will not wait between load request")
 		messageIntervalInSec = flag.Int("message-interval", 1, "Time interval in seconds to publish message")
@@ -111,23 +111,23 @@ func main() {
 			log.Println("Starting client ", i)
 		}
 		c := &Client{
-			ID:          i,
-			ClientID:    *clientPrefix,
-			BrokerURL:   *broker,
-			BrokerUser:  *username,
-			BrokerPass:  *password,
-			MsgTopic:    *topic,
-			MsgPayload:  *payload,
-			MsgSize:     *size,
-			MsgCount:    *count,
-			MsgQoS:      byte(*qos),
-			Quiet:       *quiet,
-			WaitTimeout: time.Duration(*wait) * time.Millisecond,
-			TLSConfig:   tlsConfig,
+			ID:              i,
+			ClientID:        *clientPrefix,
+			BrokerURL:       *broker,
+			BrokerUser:      *username,
+			BrokerPass:      *password,
+			MsgTopic:        *topic,
+			MsgPayload:      *payload,
+			MsgSize:         *size,
+			MsgCount:        *count,
+			MsgQoS:          byte(*qos),
+			Quiet:           *quiet,
+			WaitTimeout:     time.Duration(*wait) * time.Millisecond,
+			TLSConfig:       tlsConfig,
 			MessageInterval: *messageIntervalInSec,
 		}
 		go c.Run(resCh)
-        time.Sleep(time.Duration(sleepTime * 1000) * time.Millisecond)
+		time.Sleep(time.Duration(sleepTime*1000) * time.Millisecond)
 	}
 
 	// collect the results
@@ -233,8 +233,12 @@ func generateTLSConfig(certFile string, keyFile string, caFile string, insecure
 		if err != nil {
 			log.Fatalf("Error reading CA certificate file: %v", err)
 		}
+
 		caCertPool = x509.NewCertPool()
-		caCertPool.AppendCertsFromPEM(caCert)
+		ok := caCertPool.AppendCertsFromPEM(caCert)
+		if !ok {
+			log.Fatalf("Error parsing CA certificate %v", certFile)
+		}
 	}
 
 	cfg := tls.Config{