diff --git a/src/IO/http.cc b/src/IO/http.cc
index 159b394..7bc1029 100644
--- a/src/IO/http.cc
+++ b/src/IO/http.cc
@@ -93,7 +93,7 @@ static void Http_socket_enqueue(Server_t *srv, SocketData_t* sock);
 static Server_t *Http_server_get(const char *host, uint_t port, bool_t https);
 static void Http_server_remove(Server_t *srv);
 static void Http_connect_socket(ChainLink *Info);
-static char *Http_get_connect_str(const DilloUrl *url);
+static std::string Http_get_connect_str(const DilloUrl *url);
 static void Http_send_query(SocketData_t *S);
 static void Http_socket_free(int SKey);
 
@@ -507,8 +507,8 @@ static void Http_connect_tls(ChainLink *info)
    SocketData_t *S = reinterpret_cast< SocketData_t * >( a_Klist_get_data(ValidSocks, SKey) );
 
    if (S->flags & HTTP_SOCKET_USE_PROXY) {
-      char *connect_str = Http_get_connect_str(S->url);
-      DataBuf *dbuf = a_Chain_dbuf_new(connect_str, strlen(connect_str), 0);
+      auto connect_str = Http_get_connect_str(S->url);
+      DataBuf *dbuf = a_Chain_dbuf_new(connect_str.data(), connect_str.size(), 0);
 
       MSG_BW(S->web, 1, "Tunnel secure connection through proxy...");
       a_Chain_bfcb(OpSend, info, &S->SockFD, const_cast< void * >( static_cast< const void * >( "FD" ) ));
@@ -516,7 +516,6 @@ static void Http_connect_tls(ChainLink *info)
       a_Chain_bcb(OpSend, info, dbuf, NULL);
 
       dFree(dbuf);
-      dFree(connect_str);
    } else {
       MSG_BW(S->web, 1, "Secure connection negotiation...");
       a_Tls_connect(S->SockFD, S->url);
@@ -694,42 +693,33 @@ static int Http_must_use_proxy(const char *hostname)
 /**
  * Return a new string for the request used to tunnel HTTPS through a proxy.
  */
-static char *Http_get_connect_str(const DilloUrl *url)
+static std::string Http_get_connect_str(const DilloUrl *url)
 {
-   Dstr *dstr;
    const char *auth1;
    int auth_len;
-   char *auth2, *proxy_auth, *retstr;
+   std::string auth2;
+   std::string proxy_auth;
+   std::string dstr;
+   using namespace std::literals::string_literals;
 
    dReturn_val_if_fail(Http_must_use_proxy(URL_HOST(url)), NULL);
 
-   dstr = dStr_new("");
    auth1 = URL_AUTHORITY(url);
    auth_len = strlen(auth1);
    if (auth_len > 0 && !isdigit(auth1[auth_len - 1]))
       /* if no port number, add HTTPS port */
-      auth2 = dStrconcat(auth1, ":443", NULL);
+      auth2 = auth1 + ":443"s;
    else
-      auth2 = dStrdup(auth1);
-   proxy_auth = HTTP_Proxy_Auth_base64 ?
-                   dStrconcat ("Proxy-Authorization: Basic ",
-                               HTTP_Proxy_Auth_base64, "\r\n", NULL) :
-                   dStrdup("");
-   dStr_sprintfa(
-      dstr,
-      "CONNECT %s HTTP/1.1\r\n"
-      "Host: %s\r\n"
-      "%s"
-      "\r\n",
-      auth2,
-      auth2,
-      proxy_auth);
+      auth2 = auth1;
+   if (HTTP_Proxy_Auth_base64)
+      proxy_auth = "Proxy-Authorization: Basic "s +
+                               HTTP_Proxy_Auth_base64 + "\r\n";
+   dstr+= "CONNECT " + auth2 + " HTTP/1.1\r\n"
+      + "Host: " + auth2 + " \r\n"
+      + proxy_auth
+      + "\r\n";
 
-   dFree(auth2);
-   dFree(proxy_auth);
-   retstr = dstr->str;
-   dStr_free(dstr, 0);
-   return retstr;
+   return dstr;
 }
 
 /**
@@ -784,7 +774,6 @@ static void Http_dns_cb(int Status, Dlist *addr_list, void *data)
 static int Http_get(ChainLink *Info, void *Data1)
 {
    SocketData_t *S;
-   char *hostname;
    const DilloUrl *url;
 
    S = reinterpret_cast< SocketData_t * >( a_Klist_get_data(ValidSocks, VOIDP2INT(Info->LocalKey)) );
@@ -800,20 +789,19 @@ static int Http_get(ChainLink *Info, void *Data1)
    } else {
       url = S->web->url;
    }
-   hostname = dStrdup(URL_HOST(url));
+   std::string hostname = URL_HOST(url);
    S->connect_port = URL_PORT(url);
    S->url = a_Url_dup(S->web->url).release();
    if (!dStrAsciiCasecmp(URL_SCHEME(S->url), "https"))
       S->flags |= HTTP_SOCKET_TLS;
 
    /* Let the user know what we'll do */
-   MSG_BW(S->web, 1, "DNS resolving %s", hostname);
+   MSG_BW(S->web, 1, "DNS resolving %s", hostname.c_str());
 
    /* Let the DNS engine resolve the hostname, and when done,
     * we'll try to connect the socket from the callback function */
-   a_Dns_resolve(hostname, Http_dns_cb, Info->LocalKey);
+   a_Dns_resolve(hostname.c_str(), Http_dns_cb, Info->LocalKey);
 
-   dFree(hostname);
    return 0;
 }