change LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION user param usage

Also audit the bail_nuke_ah usage as Daniel Griscom suggested.

Signed-off-by: Andy Green <andy.green@linaro.org>

diff --git a/changelog b/changelog
index f6b85d9..21ecb05 100644 (file)
--- a/changelog
+++ b/changelog
@@ -31,6 +31,12 @@ User api additions
  - there's a new, optional callback LWS_CALLBACK_CLOSED_HTTP which gets
        called when an HTTP protocol socket closes
 
+ - for LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION callback, the user_space alloc
+       has already been done before the callback happens.  That means we can
+       use the user parameter to the callback to contain the user pointer, and
+       move the protocol name to the "in" parameter.  The docs for this
+       callback are also updated to reflect how to check headers in there.
+
 
 User api changes
 ----------------

diff --git a/lib/handshake.c b/lib/handshake.c
index 410355e..3007426 100644 (file)
--- a/lib/handshake.c
+++ b/lib/handshake.c
@@ -152,7 +152,7 @@ libwebsocket_read(struct libwebsocket_context *context,
 
                        if (n) {
                                lwsl_info("LWS_CALLBACK_HTTP closing\n");
-                               goto bail;
+                               goto bail; /* struct ah ptr already nuked */
                        }
 
                        return 0;
@@ -196,6 +196,10 @@ libwebsocket_read(struct libwebsocket_context *context,
                        }
                }
 
+               /* allocate wsi->user storage */
+               if (libwebsocket_ensure_user_space(wsi))
+                               goto bail_nuke_ah;
+
                /*
                 * Give the user code a chance to study the request and
                 * have the opportunity to deny it
@@ -203,10 +207,10 @@ libwebsocket_read(struct libwebsocket_context *context,
 
                if ((wsi->protocol->callback)(wsi->protocol->owning_server, wsi,
                                LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION,
-                               lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL),
-                                                                    NULL, 0)) {
+                               wsi->user_space,
+                             lws_hdr_simple_ptr(wsi, WSI_TOKEN_PROTOCOL), 0)) {
                        lwsl_warn("User code denied connection\n");
-                       goto bail;
+                       goto bail_nuke_ah;
                }
 
 
@@ -220,17 +224,17 @@ libwebsocket_read(struct libwebsocket_context *context,
                        lwsl_parser("lws_parse calling handshake_04\n");
                        if (handshake_0405(context, wsi)) {
                                lwsl_info("hs0405 has failed the connection\n");
-                               goto bail;
+                               goto bail_nuke_ah;
                        }
                        break;
 
                default:
                        lwsl_warn("Unknown client spec version %d\n",
                                                       wsi->ietf_spec_revision);
-                       goto bail;
+                       goto bail_nuke_ah;
                }
 
-               /* drop the header info */
+               /* drop the header info -- no bail_nuke_ah after this */
 
                if (wsi->u.hdr.ah)
                        free(wsi->u.hdr.ah);

diff --git a/lib/libwebsockets.h b/lib/libwebsockets.h
index 9f686bd..cf45947 100644 (file)
--- a/lib/libwebsockets.h
+++ b/lib/libwebsockets.h
@@ -480,11 +480,14 @@ struct libwebsocket_extension;
  *     LWS_CALLBACK_FILTER_PROTOCOL_CONNECTION: called when the handshake has
  *             been received and parsed from the client, but the response is
  *             not sent yet.  Return non-zero to disallow the connection.
- *             @user is a pointer to an array of struct lws_tokens, you can
- *             use the header enums lws_token_indexes from libwebsockets.h
- *             to check for and read the supported header presence and
- *             content before deciding to allow the handshake to proceed or
- *             to kill the connection.
+ *             @user is a pointer to the connection user space allocation,
+ *             @in is the requested protocol name
+ *             In your handler you can use the public APIs
+ *             lws_hdr_total_length() / lws_hdr_copy() to access all of the
+ *             headers using the header enums lws_token_indexes from
+ *             libwebsockets.h to check for and read the supported header
+ *             presence and content before deciding to allow the handshake
+ *             to proceed or to kill the connection.
  *
  *     LWS_CALLBACK_OPENSSL_LOAD_EXTRA_CLIENT_VERIFY_CERTS: if configured for
  *             including OpenSSL support, this callback allows your user code