Tag Archives: mqtt

[Solved] mosquitto log Error: SSL routines:SSL3_READ_BYTES:tlsv1 alert decrypt error

Problem description

The following errors occurred in the TLS/SSL of mosquitto during the test today, indicating that the error occurred in the TLS version:

I know that the default tls version of mosquitto_pub and mosquitto_sub is tlsv1.2, however, the version of openssl in my virtual machine is 1.1.1, and the tls_version tlsv1.1 is configured in mosquitto.conf (one-way authentication is configured here, two-way authentication is also (here the configuration is one-way authentication, two-way authentication is also applicable), so there will be tls version error.

Solution:

For C programs of mosquitto library
Use the API mosquitto_tls_set() before attaching mosquitto_tls_opts_set(), this API can set the corresponding tls version of the client, note that the tls version defaults to tlsv1.2.

The code is as follows:

int    rc = -1;

rc = mosquitto_tls_opts_set(mosq, 1, "tlsv1.1", NULL);
if( rc != MOSQ_ERR_SUCCESS )
{
    printf("mosquitto_tls_opts_set failure.\n");
    exit(1);
}

rc = mosquitto_tls_set(mosq, CAFILE, CAPATH, CERTFILE, KEYFILE, NULL);
if( rc != MOSQ_ERR_SUCCESS )
{
    printf("mosquitto_tls_set failure.\n");
    exit(1);
}

On the mosquitto command line

The following is the test of one-way authentication (in case of two-way authentication, add the certificate and key by yourself)

mosquitto_ pub -h 192.168.222.130 -p 8884 -t “hello” -m “hi sub” –tls-version tlsv1. 1 –cafile ./ ca/ca.crt

mosquitto_ sub -h 192.168.222.130 -p 8884 -t “hello” –tls-version tlsv1. 1 –cafile ./ ca/ca.crt

If the problem is solved successfully, it can be connected normally:

[Solved] mqtt.js Error: n.createConnection is not a function

Reason: This is a version problem, 4.2.X+ (this is also the problem when I use the latest version, which may be improved in the future)

Solution: use the lower version, I use 4.1.X is OK.

Here is the output of the client after the connection is successful

Vue solution:
Vue installation. Not only the version needs to be modified, but also the ^  in front of the version needs to be removed (in packpage.json), but there is no Vue test. You can try it (a picture of other blogs is cut here)

[Solved] mqttfx Error: Error Loading External CSS Resource

1. Error message

2. Reasons

This is because the custom mode is selected when using mqtt.fx. The software remembers this configuration and does not completely clean the configuration when reinstalling or uninstalling

3. Treatment method

Modify the configuration file
Path: C:\users\{administrator user name}\appdata\local\mqtt FX
the following: mqttfx config.xml
Modify: modify custom to light

<styleName>LIGHT</styleName>