namecoin.py

"""
Namecoin queries
"""
# pylint: disable=too-many-branches,protected-access

import base64
import json
import os
import socket
import sys

from six.moves import http_client as httplib

import defaults
from addresses import decodeAddress
from bmconfigparser import config
from debug import logger
from tr import _translate  # translate

configSection = "bitmessagesettings"


class RPCError(Exception):
    """Error thrown when the RPC call returns an error."""

    error = None

    def __init__(self, data):
        super(RPCError, self).__init__()
        self.error = data

    def __str__(self):
        return "{0}: {1}".format(type(self).__name__, self.error)


class namecoinConnection(object):
    """This class handles the Namecoin identity integration."""

    user = None
    password = None
    host = None
    port = None
    nmctype = None
    bufsize = 4096
    queryid = 1
    con = None

    def __init__(self, options=None):
        """
        Initialise.  If options are given, take the connection settings from
        them instead of loading from the configs.  This can be used to test
        currently entered connection settings in the config dialog without
        actually changing the values (yet).
        """
        if options is None:
            self.nmctype = config.get(
                configSection, "namecoinrpctype")
            self.host = config.get(
                configSection, "namecoinrpchost")
            self.port = int(config.get(
                configSection, "namecoinrpcport"))
            self.user = config.get(
                configSection, "namecoinrpcuser")
            self.password = config.get(
                configSection, "namecoinrpcpassword")
        else:
            self.nmctype = options["type"]
            self.host = options["host"]
            self.port = int(options["port"])
            self.user = options["user"]
            self.password = options["password"]

        assert self.nmctype == "namecoind" or self.nmctype == "nmcontrol"
        if self.nmctype == "namecoind":
            self.con = httplib.HTTPConnection(self.host, self.port, timeout=3)

    def query(self, identity):
        """
        Query for the bitmessage address corresponding to the given identity
        string.  If it doesn't contain a slash, id/ is prepended.  We return
        the result as (Error, Address) pair, where the Error is an error
        message to display or None in case of success.
        """
        slashPos = identity.find("/")
        if slashPos < 0:
            display_name = identity
            identity = "id/" + identity
        else:
            display_name = identity.split("/")[1]

        try:
            if self.nmctype == "namecoind":
                res = self.callRPC("name_show", [identity])
                res = res["value"]
            elif self.nmctype == "nmcontrol":
                res = self.callRPC("data", ["getValue", identity])
                res = res["reply"]
                if not res:
                    return (_translate(
                        "MainWindow", "The name %1 was not found."
                    ).arg(identity.decode("utf-8", "ignore")), None)
            else:
                assert False
        except RPCError as exc:
            logger.exception("Namecoin query RPC exception")
            if isinstance(exc.error, dict):
                errmsg = exc.error["message"]
            else:
                errmsg = exc.error
            return (_translate(
                "MainWindow", "The namecoin query failed (%1)"
            ).arg(errmsg.decode("utf-8", "ignore")), None)
        except AssertionError:
            return (_translate(
                "MainWindow", "Unknown namecoin interface type: %1"
            ).arg(self.nmctype.decode("utf-8", "ignore")), None)
        except Exception:
            logger.exception("Namecoin query exception")
            return (_translate(
                "MainWindow", "The namecoin query failed."), None)

        try:
            res = json.loads(res)
        except ValueError:
            pass
        else:
            try:
                display_name = res["name"]
            except KeyError:
                pass
            res = res.get("bitmessage")

        valid = decodeAddress(res)[0] == "success"
        return (
            None, "%s <%s>" % (display_name, res)
        ) if valid else (
            _translate(
                "MainWindow",
                "The name %1 has no associated Bitmessage address."
            ).arg(identity.decode("utf-8", "ignore")), None)

    def test(self):
        """
        Test the connection settings.  This routine tries to query a "getinfo"
        command, and builds either an error message or a success message with
        some info from it.
        """
        try:
            if self.nmctype == "namecoind":
                try:
                    vers = self.callRPC("getinfo", [])["version"]
                except RPCError:
                    vers = self.callRPC("getnetworkinfo", [])["version"]

                v3 = vers % 100
                vers = vers / 100
                v2 = vers % 100
                vers = vers / 100
                v1 = vers
                if v3 == 0:
                    versStr = "0.%d.%d" % (v1, v2)
                else:
                    versStr = "0.%d.%d.%d" % (v1, v2, v3)
                message = (
                    "success",
                    _translate(
                        "MainWindow",
                        "Success!  Namecoind version %1 running.").arg(
                            versStr.decode("utf-8", "ignore")))

            elif self.nmctype == "nmcontrol":
                res = self.callRPC("data", ["status"])
                prefix = "Plugin data running"
                if ("reply" in res) and res["reply"][:len(prefix)] == prefix:
                    return (
                        "success",
                        _translate(
                            "MainWindow",
                            "Success!  NMControll is up and running."
                        )
                    )

                logger.error("Unexpected nmcontrol reply: %s", res)
                message = (
                    "failed",
                    _translate(
                        "MainWindow",
                        "Couldn\'t understand NMControl."
                    )
                )

            else:
                sys.exit("Unsupported Namecoin type")

            return message

        except Exception:
            logger.info("Namecoin connection test failure")
            return (
                "failed",
                _translate(
                    "MainWindow", "The connection to namecoin failed.")
            )

    def callRPC(self, method, params):
        """Helper routine that actually performs an JSON RPC call."""

        data = {"method": method, "params": params, "id": self.queryid}
        if self.nmctype == "namecoind":
            resp = self.queryHTTP(json.dumps(data))
        elif self.nmctype == "nmcontrol":
            resp = self.queryServer(json.dumps(data))
        else:
            assert False
        val = json.loads(resp)

        if val["id"] != self.queryid:
            raise Exception("ID mismatch in JSON RPC answer.")

        if self.nmctype == "namecoind":
            self.queryid = self.queryid + 1

        error = val["error"]
        if error is None:
            return val["result"]

        if isinstance(error, bool):
            raise RPCError(val["result"])
        raise RPCError(error)

    def queryHTTP(self, data):
        """Query the server via HTTP."""

        result = None

        try:
            self.con.putrequest("POST", "/")
            self.con.putheader("Connection", "Keep-Alive")
            self.con.putheader("User-Agent", "bitmessage")
            self.con.putheader("Host", self.host)
            self.con.putheader("Content-Type", "application/json")
            self.con.putheader("Content-Length", str(len(data)))
            self.con.putheader("Accept", "application/json")
            authstr = "%s:%s" % (self.user, self.password)
            self.con.putheader(
                "Authorization", "Basic %s" % base64.b64encode(authstr))
            self.con.endheaders()
            self.con.send(data)
        except:  # noqa:E722
            logger.info("HTTP connection error")
            return None

        try:
            resp = self.con.getresponse()
            result = resp.read()
            if resp.status != 200:
                raise Exception(
                    "Namecoin returned status"
                    " %i: %s" % (resp.status, resp.reason))
        except:  # noqa:E722
            logger.info("HTTP receive error")
            return None

        return result

    def queryServer(self, data):
        """Helper routine sending data to the RPC "
        "server and returning the result."""

        try:
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
            s.settimeout(3)
            s.connect((self.host, self.port))
            s.sendall(data)
            result = ""

            while True:
                tmp = s.recv(self.bufsize)
                if not tmp:
                    break
                result += tmp

            s.close()

            return result

        except socket.error as exc:
            raise Exception("Socket error in RPC connection: %s" % exc)


def lookupNamecoinFolder():
    """
    Look up the namecoin data folder.

    .. todo:: Check whether this works on other platforms as well!
    """

    app = "namecoin"
    from os import environ, path
    if sys.platform == "darwin":
        if "HOME" in environ:
            dataFolder = path.join(os.environ["HOME"],
                                   "Library/Application Support/", app) + "/"
        else:
            sys.exit(
                "Could not find home folder, please report this message"
                " and your OS X version to the BitMessage Github."
            )

    elif "win32" in sys.platform or "win64" in sys.platform:
        dataFolder = path.join(environ["APPDATA"], app) + "\\"
    else:
        dataFolder = path.join(environ["HOME"], ".%s" % app) + "/"

    return dataFolder


def ensureNamecoinOptions():
    """
    Ensure all namecoin options are set, by setting those to default values
    that aren't there.
    """

    if not config.has_option(configSection, "namecoinrpctype"):
        config.set(configSection, "namecoinrpctype", "namecoind")
    if not config.has_option(configSection, "namecoinrpchost"):
        config.set(configSection, "namecoinrpchost", "localhost")

    hasUser = config.has_option(configSection, "namecoinrpcuser")
    hasPass = config.has_option(configSection, "namecoinrpcpassword")
    hasPort = config.has_option(configSection, "namecoinrpcport")

    # Try to read user/password from .namecoin configuration file.
    defaultUser = ""
    defaultPass = ""
    nmcFolder = lookupNamecoinFolder()
    nmcConfig = nmcFolder + "namecoin.conf"
    try:
        nmc = open(nmcConfig, "r")

        while True:
            line = nmc.readline()
            if line == "":
                break
            parts = line.split("=")
            if len(parts) == 2:
                key = parts[0]
                val = parts[1].rstrip()

                if key == "rpcuser" and not hasUser:
                    defaultUser = val
                if key == "rpcpassword" and not hasPass:
                    defaultPass = val
                if key == "rpcport":
                    defaults.namecoinDefaultRpcPort = val

        nmc.close()
    except IOError:
        logger.warning(
            "%s unreadable or missing, Namecoin support deactivated",
            nmcConfig)
    except Exception:
        logger.warning("Error processing namecoin.conf", exc_info=True)

    # If still nothing found, set empty at least.
    if not hasUser:
        config.set(configSection, "namecoinrpcuser", defaultUser)
    if not hasPass:
        config.set(configSection, "namecoinrpcpassword", defaultPass)

    # Set default port now, possibly to found value.
    if not hasPort:
        config.set(configSection, "namecoinrpcport", defaults.namecoinDefaultRpcPort)