Issue with cookies and redirects

[Xerbo]

Host operating system: output of uname -a

Linux xxx 6.11.3-200.fc40.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Oct 10 22:31:19 UTC 2024 x86_64 GNU/Linux

blackbox_exporter version: output of blackbox_exporter --version

Tested with master, 0.25.0 and 0.24.0

What is the blackbox.yml module config.

modules:
  alfresco_login:
    prober: http
    timeout: 10s
    http:
      method: POST
      body: "username=xxx&password=xxx"
      headers:
        Content-Type: application/x-www-form-urlencoded
      fail_if_body_not_matches_regexp:
        - 'Alfresco.constants.USERNAME = "xxx"'
      preferred_ip_protocol: "ip4"

What is the prometheus.yml scrape config.

N/A

What logging output did you get from adding &debug=true to the probe URL?

ts=2024-12-06T11:30:50.726812649Z caller=main.go:190 module=alfresco_login target=https://url/share/page/dologin level=info msg="Beginning probe" probe=http timeout_seconds=10
ts=2024-12-06T11:30:50.726904739Z caller=http.go:328 module=alfresco_login target=https://url/share/page/dologin level=info msg="Resolving target address" target=url ip_protocol=ip4
ts=2024-12-06T11:30:50.761472513Z caller=http.go:328 module=alfresco_login target=https://url/share/page/dologin level=info msg="Resolved target address" target=url ip=ip
ts=2024-12-06T11:30:50.761565163Z caller=client.go:259 module=alfresco_login target=https://url/share/page/dologin level=info msg="Making HTTP request" url=https://ip/share/page/dologin host=url
ts=2024-12-06T11:30:50.811980679Z caller=client.go:505 module=alfresco_login target=https://url/share/page/dologin level=info msg="Received redirect" location=https://url/share
ts=2024-12-06T11:30:50.812018849Z caller=client.go:259 module=alfresco_login target=https://url/share/page/dologin level=info msg="Making HTTP request" url=https://url/share host=
ts=2024-12-06T11:30:50.812025779Z caller=client.go:259 module=alfresco_login target=https://url/share/page/dologin level=info msg="Address does not match first address, not sending TLS ServerName" first=ip address=url
ts=2024-12-06T11:30:50.857525478Z caller=client.go:505 module=alfresco_login target=https://url/share/page/dologin level=info msg="Received redirect" location=https://url/share/
ts=2024-12-06T11:30:50.857554498Z caller=client.go:259 module=alfresco_login target=https://url/share/page/dologin level=info msg="Making HTTP request" url=https://url/share/ host=
ts=2024-12-06T11:30:50.857564648Z caller=client.go:259 module=alfresco_login target=https://url/share/page/dologin level=info msg="Address does not match first address, not sending TLS ServerName" first=ip address=url
ts=2024-12-06T11:30:50.889258093Z caller=client.go:505 module=alfresco_login target=https://url/share/page/dologin level=info msg="Received redirect" location=https://url/share/page/
ts=2024-12-06T11:30:50.889296304Z caller=client.go:259 module=alfresco_login target=https://url/share/page/dologin level=info msg="Making HTTP request" url=https://url/share/page/ host=
ts=2024-12-06T11:30:50.889303374Z caller=client.go:259 module=alfresco_login target=https://url/share/page/dologin level=info msg="Address does not match first address, not sending TLS ServerName" first=ip address=url
ts=2024-12-06T11:30:51.175720822Z caller=handler.go:119 module=alfresco_login target=https://url/share/page/dologin level=info msg="Received HTTP response" status_code=200
ts=2024-12-06T11:30:51.183517707Z caller=http.go:538 module=alfresco_login target=https://url/share/page/dologin level=error msg="Body did not match regular expression" regexp="Alfresco.constants.USERNAME = \"xxx\""
ts=2024-12-06T11:30:51.183553377Z caller=handler.go:119 module=alfresco_login target=https://url/share/page/dologin level=info msg="Response timings for roundtrip" roundtrip=0 start=2024-12-06T11:30:50.761641794Z dnsDone=2024-12-06T11:30:50.761641794Z connectDone=2024-12-06T11:30:50.766183658Z gotConn=2024-12-06T11:30:50.795895554Z responseStart=2024-12-06T11:30:50.811885588Z tlsStart=2024-12-06T11:30:50.766195598Z tlsDone=2024-12-06T11:30:50.795828913Z end=0001-01-01T00:00:00Z
ts=2024-12-06T11:30:51.183577828Z caller=handler.go:119 module=alfresco_login target=https://url/share/page/dologin level=info msg="Response timings for roundtrip" roundtrip=1 start=2024-12-06T11:30:50.81206823Z dnsDone=2024-12-06T11:30:50.812956078Z connectDone=2024-12-06T11:30:50.818057807Z gotConn=2024-12-06T11:30:50.839994839Z responseStart=2024-12-06T11:30:50.857446997Z tlsStart=2024-12-06T11:30:50.818074127Z tlsDone=2024-12-06T11:30:50.839926768Z end=0001-01-01T00:00:00Z
ts=2024-12-06T11:30:51.183585628Z caller=handler.go:119 module=alfresco_login target=https://url/share/page/dologin level=info msg="Response timings for roundtrip" roundtrip=2 start=2024-12-06T11:30:50.857618999Z dnsDone=2024-12-06T11:30:50.858515227Z connectDone=2024-12-06T11:30:50.863679927Z gotConn=2024-12-06T11:30:50.87652042Z responseStart=2024-12-06T11:30:50.889166682Z tlsStart=2024-12-06T11:30:50.863698987Z tlsDone=2024-12-06T11:30:50.87647076Z end=0001-01-01T00:00:00Z
ts=2024-12-06T11:30:51.183592268Z caller=handler.go:119 module=alfresco_login target=https://url/share/page/dologin level=info msg="Response timings for roundtrip" roundtrip=3 start=2024-12-06T11:30:50.889355444Z dnsDone=2024-12-06T11:30:50.890137072Z connectDone=2024-12-06T11:30:50.894888858Z gotConn=2024-12-06T11:30:51.118020776Z responseStart=2024-12-06T11:30:51.175681882Z tlsStart=2024-12-06T11:30:50.894901988Z tlsDone=2024-12-06T11:30:51.117976646Z end=2024-12-06T11:30:51.183547667Z
ts=2024-12-06T11:30:51.183642218Z caller=main.go:190 module=alfresco_login target=https://url/share/page/dologin level=error msg="Probe failed" duration_seconds=0.456800419

What did you do that produced an error?

Request a URL that sets cookies and then redirects.

What did you expect to see?

Cookies set on the first request are valid after a redirect.

What did you see instead?

Cookies set on the first request are only set on the resolved IP of the URL; any further redirects lack these cookies as they use the actual URL.

Bypassing the following block of code fixes the issue:

if ip != nil {
	// Replace the host field in the URL with the IP we resolved.
	if targetPort == "" {
		if strings.Contains(ip.String(), ":") {
			targetURL.Host = "[" + ip.String() + "]"
		} else {
			targetURL.Host = ip.String()
		}
	} else {
		targetURL.Host = net.JoinHostPort(ip.String(), targetPort)
	}
}