commit be5a83e84a34091f2a4e3c6dfb911b20e78e690c
Author: usa <usa@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Wed Jul 7 10:34:08 2021 +0000
Ignore IP addresses in PASV responses by default, and add new option use_pasv_ip
This fixes CVE-2021-31810.
Reported by Alexandr Savca.
Co-authored-by: Shugo Maeda <shugo@ruby-lang.org>
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_6@67949 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
diff --git a/lib/net/ftp.rb b/lib/net/ftp.rb
index e68d825dcf..c5d669d898 100644
--- a/lib/net/ftp.rb
+++ b/lib/net/ftp.rb
@@ -97,6 +97,10 @@ class FTP < Protocol
# When +true+, the connection is in passive mode. Default: +true+.
attr_accessor :passive
+ # When +true+, use the IP address in PASV responses. Otherwise, it uses
+ # the same IP address for the control connection. Default: +false+.
+ attr_accessor :use_pasv_ip
+
# When +true+, all traffic to and from the server is written
# to +$stdout+. Default: +false+.
attr_accessor :debug_mode
@@ -205,6 +209,9 @@ def FTP.open(host, *args)
# handshake.
# See Net::FTP#ssl_handshake_timeout for
# details. Default: +nil+.
+ # use_pasv_ip:: When +true+, use the IP address in PASV responses.
+ # Otherwise, it uses the same IP address for the control
+ # connection. Default: +false+.
# debug_mode:: When +true+, all traffic to and from the server is
# written to +$stdout+. Default: +false+.
#
@@ -265,6 +272,7 @@ def initialize(host = nil, user_or_options = {}, passwd = nil, acct = nil)
@open_timeout = options[:open_timeout]
@ssl_handshake_timeout = options[:ssl_handshake_timeout]
@read_timeout = options[:read_timeout] || 60
+ @use_pasv_ip = options[:use_pasv_ip] || false
if host
connect(host, options[:port] || FTP_PORT)
if options[:username]
@@ -1330,7 +1338,12 @@ def parse227(resp) # :nodoc:
raise FTPReplyError, resp
end
if m = /\((?<host>\d+(,\d+){3}),(?<port>\d+,\d+)\)/.match(resp)
- return parse_pasv_ipv4_host(m["host"]), parse_pasv_port(m["port"])
+ if @use_pasv_ip
+ host = parse_pasv_ipv4_host(m["host"])
+ else
+ host = @bare_sock.remote_address.ip_address
+ end
+ return host, parse_pasv_port(m["port"])
else
raise FTPProtoError, resp
end
diff --git a/test/net/ftp/test_ftp.rb b/test/net/ftp/test_ftp.rb
index a5219644bb..b3fe7774ed 100644
--- a/test/net/ftp/test_ftp.rb
+++ b/test/net/ftp/test_ftp.rb
@@ -61,7 +61,7 @@ def test_connect_fail
end
def test_parse227
- ftp = Net::FTP.new
+ ftp = Net::FTP.new(nil, use_pasv_ip: true)
host, port = ftp.send(:parse227, "227 Entering Passive Mode (192,168,0,1,12,34)")
assert_equal("192.168.0.1", host)
assert_equal(3106, port)
@@ -80,6 +80,14 @@ def test_parse227
assert_raise(Net::FTPProtoError) do
ftp.send(:parse227, "227 ) foo bar (")
end
+
+ ftp = Net::FTP.new
+ sock = OpenStruct.new
+ sock.remote_address = OpenStruct.new
+ sock.remote_address.ip_address = "10.0.0.1"
+ ftp.instance_variable_set(:@bare_sock, sock)
+ host, port = ftp.send(:parse227, "227 Entering Passive Mode (192,168,0,1,12,34)")
+ assert_equal("10.0.0.1", host)
end
def test_parse228
@@ -2360,10 +2368,155 @@ def test_puttextfile_command_injection
end
end
+ def test_ignore_pasv_ip
+ commands = []
+ binary_data = (0..0xff).map {|i| i.chr}.join * 4 * 3
+ server = create_ftp_server(nil, "127.0.0.1") { |sock|
+ sock.print("220 (test_ftp).\r\n")
+ commands.push(sock.gets)
+ sock.print("331 Please specify the password.\r\n")
+ commands.push(sock.gets)
+ sock.print("230 Login successful.\r\n")
+ commands.push(sock.gets)
+ sock.print("200 Switching to Binary mode.\r\n")
+ line = sock.gets
+ commands.push(line)
+ data_server = TCPServer.new("127.0.0.1", 0)
+ port = data_server.local_address.ip_port
+ sock.printf("227 Entering Passive Mode (999,0,0,1,%s).\r\n",
+ port.divmod(256).join(","))
+ commands.push(sock.gets)
+ sock.print("150 Opening BINARY mode data connection for foo (#{binary_data.size} bytes)\r\n")
+ conn = data_server.accept
+ binary_data.scan(/.{1,1024}/nm) do |s|
+ conn.print(s)
+ end
+ conn.shutdown(Socket::SHUT_WR)
+ conn.read
+ conn.close
+ data_server.close
+ sock.print("226 Transfer complete.\r\n")
+ }
+ begin
+ begin
+ ftp = Net::FTP.new
+ ftp.passive = true
+ ftp.read_timeout *= 5 if defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled? # for --jit-wait
+ ftp.connect("127.0.0.1", server.port)
+ ftp.login
+ assert_match(/\AUSER /, commands.shift)
+ assert_match(/\APASS /, commands.shift)
+ assert_equal("TYPE I\r\n", commands.shift)
+ buf = ftp.getbinaryfile("foo", nil)
+ assert_equal(binary_data, buf)
+ assert_equal(Encoding::ASCII_8BIT, buf.encoding)
+ assert_equal("PASV\r\n", commands.shift)
+ assert_equal("RETR foo\r\n", commands.shift)
+ assert_equal(nil, commands.shift)
+ ensure
+ ftp.close if ftp
+ end
+ ensure
+ server.close
+ end
+ end
+
+ def test_use_pasv_ip
+ commands = []
+ binary_data = (0..0xff).map {|i| i.chr}.join * 4 * 3
+ server = create_ftp_server(nil, "127.0.0.1") { |sock|
+ sock.print("220 (test_ftp).\r\n")
+ commands.push(sock.gets)
+ sock.print("331 Please specify the password.\r\n")
+ commands.push(sock.gets)
+ sock.print("230 Login successful.\r\n")
+ commands.push(sock.gets)
+ sock.print("200 Switching to Binary mode.\r\n")
+ line = sock.gets
+ commands.push(line)
+ data_server = TCPServer.new("127.0.0.1", 0)
+ port = data_server.local_address.ip_port
+ sock.printf("227 Entering Passive Mode (127,0,0,1,%s).\r\n",
+ port.divmod(256).join(","))
+ commands.push(sock.gets)
+ sock.print("150 Opening BINARY mode data connection for foo (#{binary_data.size} bytes)\r\n")
+ conn = data_server.accept
+ binary_data.scan(/.{1,1024}/nm) do |s|
+ conn.print(s)
+ end
+ conn.shutdown(Socket::SHUT_WR)
+ conn.read
+ conn.close
+ data_server.close
+ sock.print("226 Transfer complete.\r\n")
+ }
+ begin
+ begin
+ ftp = Net::FTP.new
+ ftp.passive = true
+ ftp.use_pasv_ip = true
+ ftp.read_timeout *= 5 if defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled? # for --jit-wait
+ ftp.connect("127.0.0.1", server.port)
+ ftp.login
+ assert_match(/\AUSER /, commands.shift)
+ assert_match(/\APASS /, commands.shift)
+ assert_equal("TYPE I\r\n", commands.shift)
+ buf = ftp.getbinaryfile("foo", nil)
+ assert_equal(binary_data, buf)
+ assert_equal(Encoding::ASCII_8BIT, buf.encoding)
+ assert_equal("PASV\r\n", commands.shift)
+ assert_equal("RETR foo\r\n", commands.shift)
+ assert_equal(nil, commands.shift)
+ ensure
+ ftp.close if ftp
+ end
+ ensure
+ server.close
+ end
+ end
+
+ def test_use_pasv_invalid_ip
+ commands = []
+ binary_data = (0..0xff).map {|i| i.chr}.join * 4 * 3
+ server = create_ftp_server(nil, "127.0.0.1") { |sock|
+ sock.print("220 (test_ftp).\r\n")
+ commands.push(sock.gets)
+ sock.print("331 Please specify the password.\r\n")
+ commands.push(sock.gets)
+ sock.print("230 Login successful.\r\n")
+ commands.push(sock.gets)
+ sock.print("200 Switching to Binary mode.\r\n")
+ line = sock.gets
+ commands.push(line)
+ sock.print("227 Entering Passive Mode (999,0,0,1,48,57).\r\n")
+ commands.push(sock.gets)
+ }
+ begin
+ begin
+ ftp = Net::FTP.new
+ ftp.passive = true
+ ftp.use_pasv_ip = true
+ ftp.read_timeout *= 5 if defined?(RubyVM::MJIT) && RubyVM::MJIT.enabled? # for --jit-wait
+ ftp.connect("127.0.0.1", server.port)
+ ftp.login
+ assert_match(/\AUSER /, commands.shift)
+ assert_match(/\APASS /, commands.shift)
+ assert_equal("TYPE I\r\n", commands.shift)
+ assert_raise(SocketError) do
+ ftp.getbinaryfile("foo", nil)
+ end
+ ensure
+ ftp.close if ftp
+ end
+ ensure
+ server.close
+ end
+ end
+
private
- def create_ftp_server(sleep_time = nil)
- server = TCPServer.new(SERVER_ADDR, 0)
+ def create_ftp_server(sleep_time = nil, addr = SERVER_ADDR)
+ server = TCPServer.new(addr, 0)
@thread = Thread.start do
if sleep_time
sleep(sleep_time)