wasm: support serving wasm files

Updates README with instructions.

Change-Id: I5188d3ca267ff88a956dc17f302a70bda1046266
Signed-off-by: Ashod Nakashian <ashod.nakashian@collabora.co.uk>

wasm/README.no-container.md

@@ -61,6 +61,25 @@ This will install into `/opt/poco.emsc.3.1.30`.
 
 ## Build Online itself
 
+    # 1. Update the directories in the command below to match your system.
+    # 2. Make sure that a document called sample.docx exists in the root of
+    #    the directory set as --with-wasm-additional-files.
+
     ./autogen.sh
 	emconfigure ./configure --disable-werror --with-lokit-path=/home/tml/lo/core-cool-wasm/include --with-lo-path=/home/tml/lo/core-cool-wasm/instdir --with-lo-builddir=/home/tml/lo/core-cool-wasm --with-zstd-includes=/opt/zstd.emsc.3.1.30/include --with-zstd-libs=/opt/zstd.emsc.3.1.30/lib --with-poco-includes=/opt/poco.emsc.3.1.30/include --with-poco-libs=/opt/poco.emsc.3.1.30/lib --host=wasm32-local-emscripten --with-wasm-additional-files=/home/tml/lo/online-hacking/my-sample-docs
     emmake make
+
+## Running WASM Online
+
+Once the build is done, copy the browser/dist to a safe locataion.
+E.g. cp -a browser/dist dist_wasm
+Next, re-configure Online and rebuild with normal config/settings (i.e. without WASM).
+Alternatively, you may have opted to build WASM in a separate directory.
+Either way, in the normal Online build directory, copy the wasm dist directory
+into the browser/dist, like this:
+cp -a dist_wasm browser/dist/wasm
+
+Now point your browser to https://localhost:9980/browser/c85d8681f3/wasm.html?file_path=/some/unused/path
+
+Notice that as of now, only the default sample.docx will be loaded.
+But the above steps should get one up and running.

wsd/FileServer.cpp

@@ -619,6 +619,8 @@ void FileServerRequestHandler::handleRequest(const HTTPRequest& request,
                 mimeType = "image/png";
             else if (fileType == "svg")
                 mimeType = "image/svg+xml";
+            else if (fileType == "wasm")
+                mimeType = "application/wasm";
             else
                 mimeType = "text/plain";
 
@@ -647,6 +649,12 @@ void FileServerRequestHandler::handleRequest(const HTTPRequest& request,
             response.set("Server", HTTP_SERVER_STRING);
             response.set("Date", Util::getHttpTimeNow());
 
+            if (relPath.find("wasm") != std::string::npos)
+            {
+                response.add("Cross-Origin-Opener-Policy", "same-origin");
+                response.add("Cross-Origin-Embedder-Policy", "require-corp");
+            }
+
 #if ENABLE_DEBUG
             if (std::getenv("COOL_SERVE_FROM_FS"))
             {
@@ -1152,8 +1160,6 @@ void FileServerRequestHandler::preprocessFile(const HTTPRequest& request,
         LOG_TRC("Denied all frame ancestors");
     }
 
-    csp.merge(config.getString("net.content_security_policy", ""));
-
     std::ostringstream oss;
     oss << "HTTP/1.1 200 OK\r\n"
         "Date: " << Util::getHttpTimeNow() << "\r\n"
@@ -1167,6 +1173,17 @@ void FileServerRequestHandler::preprocessFile(const HTTPRequest& request,
         "X-XSS-Protection: 1; mode=block\r\n"
         "Referrer-Policy: no-referrer\r\n";
 
+    const bool wasm = (relPath.find("wasm") != std::string::npos);
+    if (wasm)
+    {
+        oss << "Cross-Origin-Opener-Policy: same-origin\r\n";
+        oss << "Cross-Origin-Embedder-Policy: require-corp\r\n";
+
+        csp.appendDirective("script-src", "'unsafe-eval'");
+    }
+
+    csp.merge(config.getString("net.content_security_policy", ""));
+
     // Append CSP to response headers too
     oss << "Content-Security-Policy: " << csp.generate() << "\r\n";