http/util: Add is_ip() function

Author: daurnimator

doc/modules/http.util.md

@@ -51,6 +51,11 @@ Returns a boolean indicating if the passed string `method` is a "safe" method.
 See [RFC 7231 section 4.2.1](https://tools.ietf.org/html/rfc7231#section-4.2.1) for more information.
 
 
+### `is_ip(str)` <!-- --> {#http.util.is_ip}
+
+Returns a boolean indicating if the passed string `str` is a valid IP.
+
+
 ### `scheme_to_port` <!-- --> {#http.util.scheme_to_port}
 
 Map from schemes (as strings) to default ports (as integers).

http/client.lua

@@ -1,6 +1,7 @@
 local ca = require "cqueues.auxlib"
 local cs = require "cqueues.socket"
 local http_tls = require "http.tls"
+local http_util = require "http.util"
 local connection_common = require "http.connection_common"
 local onerror = connection_common.onerror
 local new_h1_connection = require "http.h1_connection".new
@@ -9,11 +10,6 @@ local openssl_ssl = require "openssl.ssl"
 local openssl_ctx = require "openssl.ssl.context"
 local openssl_verify_param = require "openssl.x509.verify_param"
 
-local EOF = require "lpeg".P(-1)
-local IPv4address = require "lpeg_patterns.IPv4".IPv4address
-local IPv6addrz = require "lpeg_patterns.IPv6".IPv6addrz
-local IPaddress = (IPv4address + IPv6addrz) * EOF
-
 -- Create a shared 'default' TLS context
 local default_ctx = http_tls.new_client_context()
 
@@ -24,7 +20,7 @@ local function negotiate(s, options, timeout)
 	if tls then
 		local ctx = options.ctx or default_ctx
 		local ssl = openssl_ssl.new(ctx)
-		local ip = options.host and IPaddress:match(options.host)
+		local ip = options.host and http_util.is_ip(options.host)
 		if options.sendname ~= nil then
 			if options.sendname then -- false indicates no sendname wanted
 				ssl:setHostName(options.sendname)

http/util.lua

@@ -1,5 +1,9 @@
 local lpeg = require "lpeg"
 local http_patts = require "lpeg_patterns.http"
+local IPv4_patts = require "lpeg_patterns.IPv4"
+local IPv6_patts = require "lpeg_patterns.IPv6"
+
+local EOF = lpeg.P(-1)
 
 -- Encodes a character as a percent encoded string
 local function char_to_pchar(c)
@@ -138,6 +142,11 @@ local function is_safe_method(method)
 	return safe_methods[method] or false
 end
 
+local IPaddress = (IPv4_patts.IPv4address + IPv6_patts.IPv6addrz) * EOF
+local function is_ip(str)
+	return IPaddress:match(str) ~= nil
+end
+
 local scheme_to_port = {
 	http = 80;
 	ws = 80;
@@ -193,7 +202,6 @@ end
 -- This pattern checks if it's argument is a valid token, if so, it returns it as is.
 -- Otherwise, it returns it as a quoted string (with any special characters escaped)
 local maybe_quote do
-	local EOF = lpeg.P(-1)
 	local patt = http_patts.token * EOF
 		+ lpeg.Cs(lpeg.Cc'"' * ((lpeg.S"\\\"") / "\\%0" + http_patts.qdtext)^0 * lpeg.Cc'"') * EOF
 	maybe_quote = function (s)
@@ -254,6 +262,7 @@ return {
 	dict_to_query = dict_to_query;
 	resolve_relative_path = resolve_relative_path;
 	is_safe_method = is_safe_method;
+	is_ip = is_ip;
 	scheme_to_port = scheme_to_port;
 	split_authority = split_authority;
 	to_authority = to_authority;

spec/util_spec.lua

@@ -64,6 +64,17 @@ describe("http.util module", function()
 		assert.same(false, util.is_safe_method "POST")
 		assert.same(false, util.is_safe_method "PUT")
 	end)
+	it("is_ip works", function()
+		assert.same(true, util.is_ip "127.0.0.1")
+		assert.same(true, util.is_ip "192.168.1.1")
+		assert.same(true, util.is_ip "::")
+		assert.same(true, util.is_ip "::1")
+		assert.same(true, util.is_ip "2001:0db8:85a3:0042:1000:8a2e:0370:7334")
+		assert.same(true, util.is_ip "::FFFF:204.152.189.116")
+		assert.same(false, util.is_ip "not an ip")
+		assert.same(false, util.is_ip "0x80")
+		assert.same(false, util.is_ip "::FFFF:0.0.0")
+	end)
 	it("split_authority works", function()
 		assert.same({"example.com", 80}, {util.split_authority("example.com", "http")})
 		assert.same({"example.com", 8000}, {util.split_authority("example.com:8000", "http")})