diff --git a/prober/tls_test.go b/prober/tls_test.go
new file mode 100644
index 0000000..6ffbab9
--- /dev/null
+++ b/prober/tls_test.go
@@ -0,0 +1,86 @@
+package prober
+
+import (
+	"testing"
+)
+
+func TestDecodeCertificates(t *testing.T) {
+	data := []byte(`
+-----BEGIN CERTIFICATE-----
+MIIFszCCA5ugAwIBAgIUdpzowWDU/AI7QBhLSRB9DPqpWvcwDQYJKoZIhvcNAQEL
+BQAwaTELMAkGA1UEBhMCWFgxEjAQBgNVBAgMCVN0YXRlTmFtZTERMA8GA1UEBwwI
+Q2l0eU5hbWUxFDASBgNVBAoMC0NvbXBhbnlOYW1lMQwwCgYDVQQLDANGb28xDzAN
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+AghlR24hUL1uslJOjLFc4BwLmlv/4Iy+b/3iQWY+yoban/OLZo6gCZx/4Nvg5R9e
+tcuxgn5Jhm2T/e8REucXQfiqKgxQVibFmqXeLH3Yj7ussA5t/ozo4VuypXUnnil0
+hB+PQsViaHFId1LyBKFwMoA6JzlNle6cbWVtXJswffkjk0UUr26SLHMV87lrk2kn
+IQ7ROZcT8K7gzzTxuiC2g6npmG1fDfgmgJeS7IqgiFcRTKa0hj6bvc/WoHoCpLNs
+v5KXxrGlqibeNjyc3Wng6S0Kpg6YNqU=
+-----END CERTIFICATE-----
+-----BEGIN TRUSTED CERTIFICATE-----
+MIIF7zCCA9egAwIBAgIUZXsnB0gxoPSFaUjnQeLwTW+sqbYwDQYJKoZIhvcNAQEL
+BQAwgYYxCzAJBgNVBAYTAlhYMRIwEAYDVQQIDAlTdGF0ZU5hbWUxETAPBgNVBAcM
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+AoICAQDJ+g1z+nZFj0DFc+wV1AH4giAqDFhwx25yziaQJnHkoXpllN0bRpr50Fhx
+QsMuMqjMCM0eFPo7kDWSrAUusdh3j1jdF7KidZRZdyUgioQvbmNtqtwdU/38Gq0s
+yTspOTZTWziIMFsLYxvFb0Ia8dwQFvyDB3pM1/eXFJMr2Cz/nF4/g4IUFEtPY2pe
+4sQDMhszvROMfI5LB4SmGiim/zUS7+ZDEQigf10/CrbLntjXHiFy+V0hcrDQXkuY
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+z1+cZEuHBF7Jk5xThXCCFwuBC/KREvRuU2LyAhm9RV1ci8XyYwIDAQABo1MwUTAd
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++N7umRO27agIYVJ71mxlS7rD1SItBKZ+g4/Lt3sr/iDM0kIhWjWdQiYgJMNhH2Mt
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++u5a1nHjtrAvLdNti8o82EUScK4j91CODCm5bv2KDMIUUv+1O83UMicK8DLSIi0P
+1acuIdbRrY5JiYewCC+NFCfODZT6y00QL7aF9cbT+ZySiYtpBUiLFlIZCw4dcJ6r
+yYJca1gv+kqZugdgLD7nXWIzXgfreQ+Q/BiVouXroXaWqU/9dqzGw4LlPSpyqI9o
+nFdu970j4BvVc809i1aNo3odGz9yRx7wOOMyiyHoRpYenlf3hFbqJHS2FUgJ/Ajl
+TC1joWDPdwdqQY56WOpk2LMK1KJuMYQEEHb3Ib0ZaxXAT6Nd12VashG5gYhw9vGn
+aZ3nCnZFahgB2tB5DtkK+p0PQVpZOv6/0CKSsfQkBFLTjeVIRnlL/UlK3VlwHH9h
+0LfsLFabedOS9R1XIaQ7aKXPK4tKmNb5H/ONzH2zxU5Oqoo=
+-----END TRUSTED CERTIFICATE-----
+`)
+
+	certs, err := decodeCertificates(data)
+	if err != nil {
+		t.Errorf("unexpected error: %s", err)
+	}
+
+	if len(certs) != 2 {
+		t.Errorf("unexpected number of certs: %d", len(certs))
+	}
+}