diff options
| -rw-r--r-- | net/connect.lua | 78 | ||||
| -rw-r--r-- | net/resolvers/basic.lua | 60 | ||||
| -rw-r--r-- | net/resolvers/manual.lua | 25 |
3 files changed, 163 insertions, 0 deletions
diff --git a/net/connect.lua b/net/connect.lua new file mode 100644 index 00000000..dbd09694 --- /dev/null +++ b/net/connect.lua @@ -0,0 +1,78 @@ +local server = require "net.server"; +local log = require "util.logger".init("net.connect"); +local new_id = require "util.id".short; + +local pending_connection_methods = {}; +local pending_connection_mt = { + __name = "pending_connection"; + __index = pending_connection_methods; + __tostring = function (p) + return "<pending connection "..p.id.." to "..tostring(p.target_resolver.hostname)..">"; + end; +}; + +function pending_connection_methods:log(level, message, ...) + log(level, "[pending connection %s] "..message, self.id, ...); +end + +-- pending_connections_map[conn] = pending_connection +local pending_connections_map = {}; + +local pending_connection_listeners = {}; + +local function attempt_connection(p) + p:log("debug", "Checking for targets..."); + if p.conn then + pending_connections_map[p.conn] = nil; + p.conn = nil; + end + p.target_resolver:next(function (conn_type, ip, port, extra) + p:log("debug", "Next target to try is %s:%d", ip, port); + local conn = assert(server.addclient(ip, port, pending_connection_listeners, p.options.pattern, p.options.sslctx, conn_type, extra)); + p.conn = conn; + pending_connections_map[conn] = p; + end); +end + +function pending_connection_listeners.onconnect(conn) + local p = pending_connections_map[conn]; + if not p then + log("warn", "Successful connection, but unexpected! Closing."); + conn:close(); + return; + end + pending_connections_map[conn] = nil; + p:log("debug", "Successfully connected"); + if p.listeners.onattach then + p.listeners.onattach(conn, p.data); + end + conn:setlistener(p.listeners); + return p.listeners.onconnect(conn); +end + +function pending_connection_listeners.ondisconnect(conn, reason) + local p = pending_connections_map[conn]; + if not p then + log("warn", "Failed connection, but unexpected!"); + return; + end + p:log("debug", "Connection attempt failed"); + attempt_connection(p); +end + +local function connect(target_resolver, listeners, options, data) + local p = setmetatable({ + id = new_id(); + target_resolver = target_resolver; + listeners = assert(listeners); + options = options or {}; + cb = cb; + }, pending_connection_mt); + + p:log("debug", "Starting connection process"); + attempt_connection(p); +end + +return { + connect = connect; +}; diff --git a/net/resolvers/basic.lua b/net/resolvers/basic.lua new file mode 100644 index 00000000..792e6d32 --- /dev/null +++ b/net/resolvers/basic.lua @@ -0,0 +1,60 @@ +local adns = require "net.adns"; + +local methods = {}; +local resolver_mt = { __index = methods }; + +-- Find the next target to connect to, and +-- pass it to cb() +function methods:next(cb) + if self.targets then + if #self.targets == 0 then + cb(nil); + return; + end + local next_target = table.remove(self.targets, 1); + cb(unpack(next_target, 1, 4)); + return; + end + + local targets = {}; + local n = 2; + local function ready() + n = n - 1; + if n > 0 then return; end + self.targets = targets; + self:next(cb); + end + + -- Resolve DNS to target list + local dns_resolver = adns.resolver(); + dns_resolver:lookup(function (answer) + if answer then + for _, record in ipairs(answer) do + table.insert(targets, { self.conn_type, record.a, self.port, self.extra }); + end + end + ready(); + end, self.hostname, "A", "IN"); + + dns_resolver:lookup(function (answer) + if answer then + for _, record in ipairs(answer) do + table.insert(targets, { self.conn_type.."6", record.aaaa, self.port, self.extra }); + end + end + ready(); + end, self.hostname, "AAAA", "IN"); +end + +local function new(hostname, port, conn_type, extra) + return setmetatable({ + hostname = hostname; + port = port; + conn_type = conn_type or "tcp"; + extra = extra; + }, resolver_mt); +end + +return { + new = new; +}; diff --git a/net/resolvers/manual.lua b/net/resolvers/manual.lua new file mode 100644 index 00000000..c0d4e5d5 --- /dev/null +++ b/net/resolvers/manual.lua @@ -0,0 +1,25 @@ +local methods = {}; +local resolver_mt = { __index = methods }; + +-- Find the next target to connect to, and +-- pass it to cb() +function methods:next(cb) + if #self.targets == 0 then + cb(nil); + return; + end + local next_target = table.remove(self.targets, 1); + cb(unpack(next_target, 1, 4)); +end + +local function new(targets, conn_type, extra) + return setmetatable({ + conn_type = conn_type; + extra = extra; + targets = targets or {}; + }, resolver_mt); +end + +return { + new = new; +}; |