http: auto-configure for local Tor proxy if called as 'tor'

With apts http transport supporting socks5h proxies and all the work
in terms of configuration of methods based on the name it is called with
it becomes surprisingly easy to implement Tor support equally (and
perhaps even a bit exceeding) what is available currently in
apt-transport-tor.

How this will turn out to be handled packaging wise we will see in
https://lists.debian.org/deity/2016/08/msg00012.html , but until this is
resolved we can add the needed support without actively enabling it for
now, so that this can be tested better.

4 files changed, 34 insertions, 0 deletions

diff --git a/methods/http.cc b/methods/http.cc
index 1ed2e3629..0358b50cd 100644
--- a/methods/http.cc
+++ b/methods/http.cc
@@ -357,6 +357,9 @@ bool HttpServerState::Open()
 	 Proxy = "";
    }
 
+   if (Proxy.empty() == false)
+      Owner->AddProxyAuth(Proxy, ServerName);
+
    if (Proxy.Access == "socks5h")
    {
       if (Connect(Proxy.Host, Proxy.Port, "socks", 1080, ServerFd, TimeOut, Owner) == false)
diff --git a/methods/https.cc b/methods/https.cc
index 47dce2ea0..283126f6b 100644
--- a/methods/https.cc
+++ b/methods/https.cc
@@ -213,6 +213,8 @@ bool HttpsMethod::SetupProxy()						/*{{{*/
    if (UseProxy.empty() == false)
    {
       Proxy = UseProxy;
+      AddProxyAuth(Proxy, ServerName);
+
       if (Proxy.Access == "socks5h")
 	 curl_easy_setopt(curl, CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME);
       else if (Proxy.Access == "socks5")
diff --git a/methods/server.cc b/methods/server.cc
index 7c85c8abb..0888617b1 100644
--- a/methods/server.cc
+++ b/methods/server.cc
@@ -794,3 +794,29 @@ ServerMethod::ServerMethod(std::string &&Binary, char const * const Ver,unsigned
 {
 }
 									/*}}}*/
+bool ServerMethod::Configuration(std::string Message)			/*{{{*/
+{
+   if (aptMethod::Configuration(Message) == false)
+      return false;
+
+   _config->CndSet("Acquire::tor::Proxy",
+	 "socks5h://apt-transport-tor@localhost:9050");
+   return true;
+}
+									/*}}}*/
+bool ServerMethod::AddProxyAuth(URI &Proxy, URI const &Server) const	/*{{{*/
+{
+   if (std::find(methodNames.begin(), methodNames.end(), "tor") != methodNames.end() &&
+	 Proxy.User == "apt-transport-tor" && Proxy.Password.empty())
+   {
+      std::string pass = Server.Host;
+      pass.erase(std::remove_if(pass.begin(), pass.end(), [](char const c) { return std::isalnum(c) == 0; }), pass.end());
+      if (pass.length() > 255)
+	 Proxy.Password = pass.substr(0, 255);
+      else
+	 Proxy.Password = std::move(pass);
+   }
+   // FIXME: should we support auth.conf for proxies?
+   return true;
+}
+									/*}}}*/
diff --git a/methods/server.h b/methods/server.h
index f6a635dca..1d114354f 100644
--- a/methods/server.h
+++ b/methods/server.h
@@ -156,6 +156,9 @@ class ServerMethod : public aptMethod
    virtual void SendReq(FetchItem *Itm) = 0;
    virtual std::unique_ptr<ServerState> CreateServerState(URI const &uri) = 0;
    virtual void RotateDNS() = 0;
+   virtual bool Configuration(std::string Message) APT_OVERRIDE;
+
+   bool AddProxyAuth(URI &Proxy, URI const &Server) const;
 
    ServerMethod(std::string &&Binary, char const * const Ver,unsigned long const Flags);
    virtual ~ServerMethod() {};