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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /tools/testing/selftests/bpf/progs/sockopt_sk.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/bpf/progs/sockopt_sk.c')
-rw-r--r--tools/testing/selftests/bpf/progs/sockopt_sk.c238
1 files changed, 238 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/sockopt_sk.c b/tools/testing/selftests/bpf/progs/sockopt_sk.c
new file mode 100644
index 000000000..cb990a7d3
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/sockopt_sk.c
@@ -0,0 +1,238 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <string.h>
+#include <linux/tcp.h>
+#include <linux/bpf.h>
+#include <netinet/in.h>
+#include <bpf/bpf_helpers.h>
+
+char _license[] SEC("license") = "GPL";
+
+int page_size = 0; /* userspace should set it */
+
+#ifndef SOL_TCP
+#define SOL_TCP IPPROTO_TCP
+#endif
+
+#define SOL_CUSTOM 0xdeadbeef
+
+struct sockopt_sk {
+ __u8 val;
+};
+
+struct {
+ __uint(type, BPF_MAP_TYPE_SK_STORAGE);
+ __uint(map_flags, BPF_F_NO_PREALLOC);
+ __type(key, int);
+ __type(value, struct sockopt_sk);
+} socket_storage_map SEC(".maps");
+
+SEC("cgroup/getsockopt")
+int _getsockopt(struct bpf_sockopt *ctx)
+{
+ __u8 *optval_end = ctx->optval_end;
+ __u8 *optval = ctx->optval;
+ struct sockopt_sk *storage;
+ struct bpf_sock *sk;
+
+ /* Bypass AF_NETLINK. */
+ sk = ctx->sk;
+ if (sk && sk->family == AF_NETLINK)
+ goto out;
+
+ /* Make sure bpf_get_netns_cookie is callable.
+ */
+ if (bpf_get_netns_cookie(NULL) == 0)
+ return 0;
+
+ if (bpf_get_netns_cookie(ctx) == 0)
+ return 0;
+
+ if (ctx->level == SOL_IP && ctx->optname == IP_TOS) {
+ /* Not interested in SOL_IP:IP_TOS;
+ * let next BPF program in the cgroup chain or kernel
+ * handle it.
+ */
+ goto out;
+ }
+
+ if (ctx->level == SOL_SOCKET && ctx->optname == SO_SNDBUF) {
+ /* Not interested in SOL_SOCKET:SO_SNDBUF;
+ * let next BPF program in the cgroup chain or kernel
+ * handle it.
+ */
+ goto out;
+ }
+
+ if (ctx->level == SOL_TCP && ctx->optname == TCP_CONGESTION) {
+ /* Not interested in SOL_TCP:TCP_CONGESTION;
+ * let next BPF program in the cgroup chain or kernel
+ * handle it.
+ */
+ goto out;
+ }
+
+ if (ctx->level == SOL_TCP && ctx->optname == TCP_ZEROCOPY_RECEIVE) {
+ /* Verify that TCP_ZEROCOPY_RECEIVE triggers.
+ * It has a custom implementation for performance
+ * reasons.
+ */
+
+ /* Check that optval contains address (__u64) */
+ if (optval + sizeof(__u64) > optval_end)
+ return 0; /* bounds check */
+
+ if (((struct tcp_zerocopy_receive *)optval)->address != 0)
+ return 0; /* unexpected data */
+
+ goto out;
+ }
+
+ if (ctx->level == SOL_IP && ctx->optname == IP_FREEBIND) {
+ if (optval + 1 > optval_end)
+ return 0; /* bounds check */
+
+ ctx->retval = 0; /* Reset system call return value to zero */
+
+ /* Always export 0x55 */
+ optval[0] = 0x55;
+ ctx->optlen = 1;
+
+ /* Userspace buffer is PAGE_SIZE * 2, but BPF
+ * program can only see the first PAGE_SIZE
+ * bytes of data.
+ */
+ if (optval_end - optval != page_size)
+ return 0; /* unexpected data size */
+
+ return 1;
+ }
+
+ if (ctx->level != SOL_CUSTOM)
+ return 0; /* deny everything except custom level */
+
+ if (optval + 1 > optval_end)
+ return 0; /* bounds check */
+
+ storage = bpf_sk_storage_get(&socket_storage_map, ctx->sk, 0,
+ BPF_SK_STORAGE_GET_F_CREATE);
+ if (!storage)
+ return 0; /* couldn't get sk storage */
+
+ if (!ctx->retval)
+ return 0; /* kernel should not have handled
+ * SOL_CUSTOM, something is wrong!
+ */
+ ctx->retval = 0; /* Reset system call return value to zero */
+
+ optval[0] = storage->val;
+ ctx->optlen = 1;
+
+ return 1;
+
+out:
+ /* optval larger than PAGE_SIZE use kernel's buffer. */
+ if (ctx->optlen > page_size)
+ ctx->optlen = 0;
+ return 1;
+}
+
+SEC("cgroup/setsockopt")
+int _setsockopt(struct bpf_sockopt *ctx)
+{
+ __u8 *optval_end = ctx->optval_end;
+ __u8 *optval = ctx->optval;
+ struct sockopt_sk *storage;
+ struct bpf_sock *sk;
+
+ /* Bypass AF_NETLINK. */
+ sk = ctx->sk;
+ if (sk && sk->family == AF_NETLINK)
+ goto out;
+
+ /* Make sure bpf_get_netns_cookie is callable.
+ */
+ if (bpf_get_netns_cookie(NULL) == 0)
+ return 0;
+
+ if (bpf_get_netns_cookie(ctx) == 0)
+ return 0;
+
+ if (ctx->level == SOL_IP && ctx->optname == IP_TOS) {
+ /* Not interested in SOL_IP:IP_TOS;
+ * let next BPF program in the cgroup chain or kernel
+ * handle it.
+ */
+ ctx->optlen = 0; /* bypass optval>PAGE_SIZE */
+ return 1;
+ }
+
+ if (ctx->level == SOL_SOCKET && ctx->optname == SO_SNDBUF) {
+ /* Overwrite SO_SNDBUF value */
+
+ if (optval + sizeof(__u32) > optval_end)
+ return 0; /* bounds check */
+
+ *(__u32 *)optval = 0x55AA;
+ ctx->optlen = 4;
+
+ return 1;
+ }
+
+ if (ctx->level == SOL_TCP && ctx->optname == TCP_CONGESTION) {
+ /* Always use cubic */
+
+ if (optval + 5 > optval_end)
+ return 0; /* bounds check */
+
+ memcpy(optval, "cubic", 5);
+ ctx->optlen = 5;
+
+ return 1;
+ }
+
+ if (ctx->level == SOL_IP && ctx->optname == IP_FREEBIND) {
+ /* Original optlen is larger than PAGE_SIZE. */
+ if (ctx->optlen != page_size * 2)
+ return 0; /* unexpected data size */
+
+ if (optval + 1 > optval_end)
+ return 0; /* bounds check */
+
+ /* Make sure we can trim the buffer. */
+ optval[0] = 0;
+ ctx->optlen = 1;
+
+ /* Usepace buffer is PAGE_SIZE * 2, but BPF
+ * program can only see the first PAGE_SIZE
+ * bytes of data.
+ */
+ if (optval_end - optval != page_size)
+ return 0; /* unexpected data size */
+
+ return 1;
+ }
+
+ if (ctx->level != SOL_CUSTOM)
+ return 0; /* deny everything except custom level */
+
+ if (optval + 1 > optval_end)
+ return 0; /* bounds check */
+
+ storage = bpf_sk_storage_get(&socket_storage_map, ctx->sk, 0,
+ BPF_SK_STORAGE_GET_F_CREATE);
+ if (!storage)
+ return 0; /* couldn't get sk storage */
+
+ storage->val = optval[0];
+ ctx->optlen = -1; /* BPF has consumed this option, don't call kernel
+ * setsockopt handler.
+ */
+
+ return 1;
+
+out:
+ /* optval larger than PAGE_SIZE use kernel's buffer. */
+ if (ctx->optlen > page_size)
+ ctx->optlen = 0;
+ return 1;
+}