Accept any transfer-encoding ending in chunked

src/HttpParser.h

@@ -580,8 +580,16 @@ struct HttpParser {
              * the Transfer-Encoding overrides the Content-Length. */
             if (transferEncodingString.data() != nullptr) {
 
-                /* We only support chunked */
-                if (transferEncodingString != "chunked") {
+                /* Transfer-coding names are case-insensitive (RFC 9112 7), so lowercase the value */
+                for (unsigned int i = 0; i < transferEncodingString.length(); i++) {
+                    char &c = ((char *) transferEncodingString.data())[i];
+                    if (c >= 'A' && c <= 'Z') {
+                        c |= 32;
+                    }
+                }
+
+                /* The app can support any framing including gzip, deflate, but it always needs to end with chunked */
+                if (transferEncodingString.length() < 7 || transferEncodingString.substr(transferEncodingString.length() - 7) != "chunked") {
                     return {HTTP_ERROR_400_BAD_REQUEST, FULLPTR};
                 }
 

tests/HttpParser.cpp

@@ -1,5 +1,6 @@
 #include <iostream>
 #include <cassert>
+#include <string>
 
 #include "../src/HttpParser.h"
 
@@ -35,4 +36,39 @@ int main() {
 
     std::cout << "HTTP DONE" << std::endl;
 
-}
+    /* Issue 1941: accept Transfer-Encoding when the final coding is chunked (case-insensitive). */
+    struct {
+        const char *te;
+        bool accept;
+    } cases[] = {
+        {"chunked", true},
+        {"CHUNKED", true},
+        {"gzip, chunked", true},
+        {"gzip, CHUNKED", true},
+        {"deflate, gzip, chunked", true},
+        {"identity, chunked", true},
+        {"gzip", false},
+        {"chunked, gzip", false},
+    };
+
+    for (auto &c : cases) {
+        std::string req = std::string("POST / HTTP/1.1\r\nHost: 127.0.0.1\r\nTransfer-Encoding: ") + c.te + "\r\n\r\n0\r\n\r\n";
+        unsigned int length = (unsigned int) req.size();
+        req.append(32, 'E');
+
+        void *teUser = (void *) 13;
+        uWS::HttpParser teParser;
+        auto [teErr, teReturned] = teParser.consumePostPadded(req.data(), length, teUser, nullptr, [](void *s, uWS::HttpRequest *) -> void * {
+            return s;
+        }, [](void *s, std::string_view, bool) -> void * {
+            return s;
+        });
+
+        bool accepted = teReturned == teUser;
+        if (accepted != c.accept) {
+            std::cerr << "Transfer-Encoding \"" << c.te << "\" expected " << (c.accept ? "accept" : "400")
+                      << ", got err=" << teErr << std::endl;
+            return 1;
+        }
+    }
+}