From: Amaury Denoyelle <adenoyelle@haproxy.com>
Date: Fri, 30 May 2025 13:59:04 +0000 (+0200)
Subject: MINOR: h3: complete HTTP/3 request method encoding
X-Git-Tag: v3.3-dev2~47
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a0912cf914;p=thirdparty%2Fhaproxy.git

MINOR: h3: complete HTTP/3 request method encoding

On the backend side, HTX start-line is converted into a HTTP/3 request
message. Previously, GET method was hardcoded. Implement proper method
conversion, by extracting it from the HTX start-line.

qpack_encode_method() has also been extended, so that it is able to
encode any method, either using a static table entry, or with a literal
field line with name ref representation.
---

diff --git a/include/haproxy/qpack-enc.h b/include/haproxy/qpack-enc.h
index 26061a6e0..10ad1d415 100644
--- a/include/haproxy/qpack-enc.h
+++ b/include/haproxy/qpack-enc.h
@@ -8,7 +8,7 @@ struct buffer;
 
 int qpack_encode_field_section_line(struct buffer *out);
 int qpack_encode_int_status(struct buffer *out, unsigned int status);
-int qpack_encode_method(struct buffer *out, enum http_meth_t meth);
+int qpack_encode_method(struct buffer *out, enum http_meth_t meth, struct ist other);
 int qpack_encode_scheme(struct buffer *out);
 int qpack_encode_path(struct buffer *out, const struct ist path);
 int qpack_encode_header(struct buffer *out, const struct ist n, const struct ist v);
diff --git a/src/h3.c b/src/h3.c
index de236ba4d..1ec2ae440 100644
--- a/src/h3.c
+++ b/src/h3.c
@@ -1707,6 +1707,7 @@ static int h3_req_headers_send(struct qcs *qcs, struct htx *htx)
 	enum htx_blk_type type;
 	struct htx_blk *blk;
 	struct htx_sl *sl;
+	struct ist meth;
 	int frame_length_size;  /* size in bytes of frame length varint field */
 	int ret, err, hdr;
 
@@ -1724,6 +1725,7 @@ static int h3_req_headers_send(struct qcs *qcs, struct htx *htx)
 		case HTX_BLK_REQ_SL:
 			BUG_ON_HOT(sl); /* Only one start-line expected */
 			sl = htx_get_blk_ptr(htx, blk);
+			meth = htx_sl_req_meth(sl);
 			break;
 
 		case HTX_BLK_HDR:
@@ -1757,10 +1759,8 @@ static int h3_req_headers_send(struct qcs *qcs, struct htx *htx)
 	if (qpack_encode_field_section_line(&headers_buf))
 		goto err;
 
-	/* :method */
-	if (qpack_encode_method(&headers_buf, HTTP_METH_GET))
+	if (qpack_encode_method(&headers_buf, sl->info.req.meth, meth))
 		goto err;
-	/* :scheme */
 
 	if (qpack_encode_scheme(&headers_buf))
 		goto err;
diff --git a/src/qpack-enc.c b/src/qpack-enc.c
index 6c5fd9fb3..4aebc0172 100644
--- a/src/qpack-enc.c
+++ b/src/qpack-enc.c
@@ -133,27 +133,40 @@ int qpack_encode_int_status(struct buffer *out, unsigned int status)
 }
 
 /* Returns 0 on success else non-zero. */
-int qpack_encode_method(struct buffer *out, enum http_meth_t meth)
+int qpack_encode_method(struct buffer *out, enum http_meth_t meth, struct ist other)
 {
-	int size, idx = 0;
+	int sz, idx = 0;
 
 	switch (meth) {
-	case HTTP_METH_GET: idx = 17; break;
-	default: ABORT_NOW();
+	case HTTP_METH_CONNECT: idx = 15; break;
+	case HTTP_METH_DELETE:  idx = 16; break;
+	case HTTP_METH_GET:     idx = 17; break;
+	case HTTP_METH_HEAD:    idx = 18; break;
+	case HTTP_METH_OPTIONS: idx = 19; break;
+	case HTTP_METH_POST:    idx = 20; break;
+	case HTTP_METH_PUT:     idx = 21; break;
+	default: break;
 	}
 
 	if (idx) {
-		/* method present in QPACK static table
-		 * -> indexed field line
-		 */
-		size = qpack_get_prefix_int_size(idx, 6);
-		if (b_room(out) < size)
+		/* indexed field line */
+		if (b_room(out) < 2)
 			return 1;
 
 		qpack_encode_prefix_integer(out, idx, 6, 0xc0);
 	}
 	else {
-		ABORT_NOW();
+		BUG_ON(!istlen(other)); /* non standard method, <other> must be set. */
+
+		sz = 2 + qpack_get_prefix_int_size(istlen(other), 7) + istlen(other);
+		if (b_room(out) < sz)
+			return 1;
+
+		/* literal field line with name ref */
+		qpack_encode_prefix_integer(out, 15, 4, 0x50);
+		qpack_encode_prefix_integer(out, istlen(other), 7, 0);
+		for (size_t i = 0; i < istlen(other); ++i)
+			b_putchr(out, istptr(other)[i]);
 	}
 
 	return 0;