BUG/MINOR: h3: strengthen host/authority header parsing

HTTP/3 specification has several requirement when parsing authority or
host header inside a request. However, it was until then only partially
implemented.

This commit fixes this by ensuring the following :
* reject an empty authority/host header
* reject a host header if an authority was found with a different value
* no authority neither host header present

This must be backported up to 2.6.
This commit is contained in:
Amaury Denoyelle 2023-10-09 16:14:44 +02:00
parent 9d905dfd73
commit dc750817c5

View File

@ -395,6 +395,39 @@ static int h3_check_body_size(struct qcs *qcs, int fin)
return ret;
}
/* Set <auth> authority header to the new value <value> for <qcs> stream. This
* ensures that value is conformant to the specification. If <auth> is a
* non-null length string, it ensures that <value> is identical to it.
*
* Returns 0 on success else non-zero.
*/
static int h3_set_authority(struct qcs *qcs, struct ist *auth, const struct ist value)
{
/* RFC 9114 4.3.1. Request Pseudo-Header Fields
*
* If the :scheme pseudo-header field identifies a scheme that has a
* mandatory authority component (including "http" and "https"), the
* request MUST contain either an :authority pseudo-header field or a
* Host header field. If these fields are present, they MUST NOT be
* empty. If both fields are present, they MUST contain the same value.
*/
/* Check that if a previous value is set the new value is identical. */
if (isttest(*auth) && !isteq(*auth, value)) {
TRACE_ERROR("difference between :authority and host headers", H3_EV_RX_FRAME|H3_EV_RX_HDR, qcs->qcc->conn, qcs);
return 1;
}
/* Check that value is not empty. */
if (!istlen(value)) {
TRACE_ERROR("empty :authority/host header", H3_EV_RX_FRAME|H3_EV_RX_HDR, qcs->qcc->conn, qcs);
return 1;
}
*auth = value;
return 0;
}
/* Parse from buffer <buf> a H3 HEADERS frame of length <len>. Data are copied
* in a local HTX buffer and transfer to the stream connector layer. <fin> must be
* set if this is the last data to transfer from this stream.
@ -554,7 +587,12 @@ static ssize_t h3_headers_to_htx(struct qcs *qcs, const struct buffer *buf,
len = -1;
goto out;
}
authority = list[hdr_idx].v;
if (h3_set_authority(qcs, &authority, list[hdr_idx].v)) {
h3s->err = H3_MESSAGE_ERROR;
len = -1;
goto out;
}
}
else {
TRACE_ERROR("unknown pseudo-header", H3_EV_RX_FRAME|H3_EV_RX_HDR, qcs->qcc->conn, qcs);
@ -646,7 +684,14 @@ static ssize_t h3_headers_to_htx(struct qcs *qcs, const struct buffer *buf,
goto out;
}
if (isteq(list[hdr_idx].n, ist("cookie"))) {
if (isteq(list[hdr_idx].n, ist("host"))) {
if (h3_set_authority(qcs, &authority, list[hdr_idx].v)) {
h3s->err = H3_MESSAGE_ERROR;
len = -1;
goto out;
}
}
else if (isteq(list[hdr_idx].n, ist("cookie"))) {
http_cookie_register(list, hdr_idx, &cookie, &last_cookie);
++hdr_idx;
continue;
@ -717,6 +762,20 @@ static ssize_t h3_headers_to_htx(struct qcs *qcs, const struct buffer *buf,
++hdr_idx;
}
/* RFC 9114 4.3.1. Request Pseudo-Header Fields
*
* If the :scheme pseudo-header field identifies a scheme that has a
* mandatory authority component (including "http" and "https"), the
* request MUST contain either an :authority pseudo-header field or a
* Host header field.
*/
if (!isttest(authority)) {
TRACE_ERROR("missing mandatory pseudo-header", H3_EV_RX_FRAME|H3_EV_RX_HDR, qcs->qcc->conn, qcs);
h3s->err = H3_MESSAGE_ERROR;
len = -1;
goto out;
}
if (cookie >= 0) {
if (http_cookie_merge(htx, list, cookie)) {
h3c->err = H3_INTERNAL_ERROR;