This makes several tweaks to improve the logic which decides whether we're
able to use the splice method for a new connection.
* Rather than only calling tcp_splice_conn_from_sock() in pasta mode, we
check for pasta mode within it, better localising the checks.
* Previously if we got a connection from a non-loopback address we'd
always fall back to the "tap" path, even if the connection was on a
socket in the namespace. If we did get a non-loopback address on a
namespace socket, something has gone wrong and the "tap" path certainly
won't be able to handle it. Report the error and close, rather than
passing it along to tap.
Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au>
---
inany.c | 1 -
tcp.c | 3 +--
tcp_splice.c | 49 ++++++++++++++++++++++++++++++++-----------------
3 files changed, 33 insertions(+), 20 deletions(-)
diff --git a/inany.c b/inany.c
index edf0b055..eaf2755d 100644
--- a/inany.c
+++ b/inany.c
@@ -23,7 +23,6 @@
*
* Return: On success, a non-null pointer to @dst, NULL on failure
*/
-/* cppcheck-suppress unusedFunction */
const char *inany_ntop(const union inany_addr *src, char *dst, socklen_t size)
{
const struct in_addr *v4 = inany_v4(src);
diff --git a/tcp.c b/tcp.c
index 8daefe99..052bf7cb 100644
--- a/tcp.c
+++ b/tcp.c
@@ -2733,8 +2733,7 @@ void tcp_listen_handler(struct ctx *c, union epoll_ref ref,
if (s < 0)
goto cancel;
- if (c->mode == MODE_PASTA &&
- tcp_splice_conn_from_sock(c, ref.tcp_listen, &flow->tcp_splice,
+ if (tcp_splice_conn_from_sock(c, ref.tcp_listen, &flow->tcp_splice,
s, (struct sockaddr *)&sa))
return;
diff --git a/tcp_splice.c b/tcp_splice.c
index abd698d4..3b438313 100644
--- a/tcp_splice.c
+++ b/tcp_splice.c
@@ -389,36 +389,51 @@ bool tcp_splice_conn_from_sock(const struct ctx *c,
sa_family_t af;
int s1, rc;
- ASSERT(c->mode == MODE_PASTA);
+ if (c->mode != MODE_PASTA)
+ return false;
inany_from_sockaddr(&src, &srcport, sa);
- if (!inany_is_loopback(&src))
- return false;
+ af = inany_v4(&src) ? AF_INET : AF_INET6;
- conn->flags = inany_v4(&src) ? 0 : SPLICE_V6;
- af = CONN_V6(conn) ? AF_INET6 : AF_INET;
+ switch (ref.pif) {
+ case PIF_SPLICE:
+ if (!inany_is_loopback(&src)) {
+ char str[INANY_ADDRSTRLEN];
- if (setsockopt(s0, SOL_TCP, TCP_QUICKACK, &((int){ 1 }), sizeof(int)))
- flow_trace(conn, "failed to set TCP_QUICKACK on %i", s0);
+ flow_err(conn, "Bad source address %s for splice, closing",
+ inany_ntop(&src, str, sizeof(str)));
- conn->f.type = FLOW_TCP_SPLICE;
- conn->s[0] = s0;
- conn->s[1] = -1;
- conn->pipe[0][0] = conn->pipe[0][1] = -1;
- conn->pipe[1][0] = conn->pipe[1][1] = -1;
+ /* We *don't* want to fall back to tap */
+ flow_alloc_cancel((union flow *)conn);
+ return true;
+ }
- if (ref.pif == PIF_SPLICE) {
dstport += c->tcp.fwd_out.delta[dstport];
-
s1 = tcp_conn_sock(c, af);
- } else {
- ASSERT(ref.pif == PIF_HOST);
+ break;
- dstport += c->tcp.fwd_in.delta[dstport];
+ case PIF_HOST:
+ if (!inany_is_loopback(&src))
+ return false;
+ dstport += c->tcp.fwd_in.delta[dstport];
s1 = tcp_conn_sock_ns(c, af);
+ break;
+
+ default:
+ return false;
}
+ conn->f.type = FLOW_TCP_SPLICE;
+ conn->s[0] = s0;
+ conn->s[1] = -1;
+ conn->pipe[0][0] = conn->pipe[0][1] = -1;
+ conn->pipe[1][0] = conn->pipe[1][1] = -1;
+ conn->flags = af == AF_INET ? 0 : SPLICE_V6;
+
+ if (setsockopt(s0, SOL_TCP, TCP_QUICKACK, &((int){ 1 }), sizeof(int)))
+ flow_trace(conn, "failed to set TCP_QUICKACK on %i", s0);
+
if (s1 < 0) {
flow_err(conn,
"Couldn't open connectable socket for splice: %s",
--
2.43.0