For expectation, the currently supported query types are A, AAAA

Author: wafuwafu13

check-dns/README.md

@@ -12,25 +12,26 @@ Monitor DNS response.
   -H, --host=            The name or address you want to query
   -s, --server=          DNS server you want to use for the lookup
   -p, --port=            Port number you want to use (default: 53)
-  -q, --querytype=       DNS record query type where TYPE =(A, AAAA, TXT, MX, CNAME) (default: A)
-  -c, --queryclass=      DNS record class type where TYPE =(IN, CS, CH, HS, NONE, ANY) (default: IN)
+  -q, --querytype=       DNS record query type (default: A)
+  -c, --queryclass=      DNS record class type (default: IN)
       --norec            Set not recursive mode
-  -e, --expected-string= The string you expect the DNS server to return. If multiple responses are returned at once, you have to specify whole string
+  -e, --expected-string= IP-ADDRESS string you expect the DNS server to return. If multiple IP-ADDRESS are returned at once, you have to specify whole string
 ```
 
-- The currently supported query types are A, AAAA, TXT, MX, CNAME.
 - Punycode is not supported.
 
 ### Check DNS server status
 
 If DNS server returns `NOERROR` in status of HEADER, then the checker result becomes `OK`, if not `NOERROR`, then `CRITICAL`
 
 ```
-check-dns -H example.com -s 8.8.8.8
+check-dns -H a.root-servers.net -s 8.8.8.8
 ```
 
 ### Check string DNS server returns
 
+- The currently supported query types are A, AAAA.
+
 If DNS server returns 1.1.1.1 and 2.2.2.2
 ```
 -a 1.1.1.1 -a 2.2.2.2            -> OK  
@@ -41,7 +42,7 @@ If DNS server returns 1.1.1.1 and 2.2.2.2
 -a 3.3.3.3 -a 4.4.4.4 -a 5.5.5.5 -> CRITICAL  
 ```
 ```
-check-dns -H example.com -s 8.8.8.8 -a 93.184.216.34
+check-dns -H a.root-servers.net -s 8.8.8.8 -e 198.41.0.4
 ```
 
 ## Installation
@@ -72,43 +73,3 @@ If there are no problems in the execution result, add a setting in mackerel-agen
 [plugin.checks.dns-sample]
 command = ["check-dns", "-H", "example.com", "-s", "8.8.8.8"]
 ```
-
-## NOTICES AND INFORMATION
-
-This plugin incorporates material from third parties.
-
-### miekg/dns
-
-**source**: https://github.com/miekg/dns
-
-```
-BSD 3-Clause License
-
-Copyright (c) 2009, The Go Authors. Extensions copyright (c) 2011, Miek Gieben. 
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are met:
-
-1. Redistributions of source code must retain the above copyright notice, this
-   list of conditions and the following disclaimer.
-
-2. Redistributions in binary form must reproduce the above copyright notice,
-   this list of conditions and the following disclaimer in the documentation
-   and/or other materials provided with the distribution.
-
-3. Neither the name of the copyright holder nor the names of its
-   contributors may be used to endorse or promote products derived from
-   this software without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
-AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
-FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
-SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
-CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
-OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-```

check-dns/lib/check_dns.go

@@ -16,14 +16,12 @@ type dnsOpts struct {
 	Host           string   `short:"H" long:"host" required:"true" description:"The name or address you want to query"`
 	Server         string   `short:"s" long:"server" description:"DNS server you want to use for the lookup"`
 	Port           int      `short:"p" long:"port" default:"53" description:"Port number you want to use"`
-	QueryType      string   `short:"q" long:"querytype" default:"A" description:"DNS record query type where TYPE =(A, AAAA, TXT, MX, CNAME)"`
-	QueryClass     string   `short:"c" long:"queryclass" default:"IN" description:"DNS record class type where TYPE =(IN, CS, CH, HS, NONE, ANY)"`
+	QueryType      string   `short:"q" long:"querytype" default:"A" description:"DNS record query type"`
+	QueryClass     string   `short:"c" long:"queryclass" default:"IN" description:"DNS record class type"`
 	Norec          bool     `long:"norec" description:"Set not recursive mode"`
-	ExpectedString []string `short:"e" long:"expected-string" description:"The string you expect the DNS server to return. If multiple responses are returned at once, you have to specify whole string"`
+	ExpectedString []string `short:"e" long:"expected-string" description:"IP-ADDRESS string you expect the DNS server to return. If multiple IP-ADDRESS are returned at once, you have to specify whole string"`
 }
 
-var supportedQueryType = map[string]int{"A": 1, "AAAA": 1, "TXT": 1, "MX": 1, "CNAME": 1}
-
 // Do the plugin
 func Do() {
 	opts, err := parseArgs(os.Args[1:])
@@ -54,11 +52,10 @@ func (opts *dnsOpts) run() *checkers.Checker {
 	}
 	nameserver = net.JoinHostPort(nameserver, strconv.Itoa(opts.Port))
 
-	_, ok := supportedQueryType[strings.ToUpper(opts.QueryType)]
+	queryType, ok := dns.StringToType[strings.ToUpper(opts.QueryType)]
 	if !ok {
 		return checkers.Critical(fmt.Sprintf("%s is not supported query type", opts.QueryType))
 	}
-	queryType := dns.StringToType[strings.ToUpper(opts.QueryType)]
 	queryClass, ok := dns.StringToClass[strings.ToUpper(opts.QueryClass)]
 	if !ok {
 		return checkers.Critical(fmt.Sprintf("%s is invalid query class", opts.QueryClass))
@@ -90,6 +87,11 @@ func (opts *dnsOpts) run() *checkers.Checker {
 		6: -e 3.3.3.3 -e 4.4.4.4 -e 5.5.5.5 -> CRITICAL
 	**/
 	if len(opts.ExpectedString) != 0 {
+		supportedQueryType := map[string]int{"A": 1, "AAAA": 1}
+		_, ok := supportedQueryType[strings.ToUpper(opts.QueryType)]
+		if !ok {
+			return checkers.Critical(fmt.Sprintf("%s is not supported query type. Only A, AAAA is supported for expectation.", opts.QueryType))
+		}
 		match := 0
 		for _, expectedString := range opts.ExpectedString {
 			for _, answer := range r.Answer {
@@ -100,16 +102,8 @@ func (opts *dnsOpts) run() *checkers.Checker {
 					anserWithoutHeader = t.A.String()
 				case *dns.AAAA:
 					anserWithoutHeader = t.AAAA.String()
-				case *dns.TXT:
-					anserWithoutHeader = sprintTxt(t.Txt)
-					// " is added by sprintTxt
-					expectMatch = "\"" + expectedString + "\""
-				case *dns.MX:
-					anserWithoutHeader = strconv.Itoa(int(t.Preference)) + " " + sprintName(t.Mx)
-				case *dns.CNAME:
-					anserWithoutHeader = sprintName(t.Target)
 				default:
-					return checkers.Critical(fmt.Sprintf("%s is not supported query type", opts.QueryType))
+					return checkers.Critical(fmt.Sprintf("%s is not supported query type. Only A, AAAA is supported for expectation.", opts.QueryType))
 				}
 				if anserWithoutHeader == expectMatch {
 					match += 1

check-dns/lib/check_dns_test.go

@@ -88,6 +88,11 @@ func TestCheckDns(t *testing.T) {
 			checkers.OK,
 			[]string{"status: NOERROR", "2001:503:ba3e::2:30"},
 		},
+		{
+			[]string{"-H", "a.root-servers.net", "-s", "8.8.8.8", "-q", "TXT", "-e", ""},
+			checkers.CRITICAL,
+			[]string{"is not supported query type. Only A, AAAA is supported for expectation."},
+		},
 		{
 			[]string{"-H", "a.root-servers.net", "-s", "8.8.8.8", "-e", "198.41.0.3"},
 			checkers.CRITICAL,