selftests/bpf: Implement sample udp/udp6 bpf_iter programs

On my VM, I got identical results between /proc/net/udp[6] and
the udp{4,6} bpf iterator.

For udp6:
  $ cat /sys/fs/bpf/p1
    sl  local_address                         remote_address                        st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode ref pointer drops
   1405: 000080FE00000000FF7CC4D0D9EFE4FE:0222 00000000000000000000000000000000:0000 07 00000000:00000000 00:00000000 00000000   193        0 19183 2 0000000029eab111 0
  $ cat /proc/net/udp6
    sl  local_address                         remote_address                        st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode ref pointer drops
   1405: 000080FE00000000FF7CC4D0D9EFE4FE:0222 00000000000000000000000000000000:0000 07 00000000:00000000 00:00000000 00000000   193        0 19183 2 0000000029eab111 0

For udp4:
  $ cat /sys/fs/bpf/p4
    sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode ref pointer drops
   2007: 00000000:1F90 00000000:0000 07 00000000:00000000 00:00000000 00000000     0        0 72540 2 000000004ede477a 0
  $ cat /proc/net/udp
    sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode ref pointer drops
   2007: 00000000:1F90 00000000:0000 07 00000000:00000000 00:00000000 00000000     0        0 72540 2 000000004ede477a 0

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200623230822.3989299-1-yhs@fb.com

diff --git a/tools/testing/selftests/bpf/progs/bpf_iter.h b/tools/testing/selftests/bpf/progs/bpf_iter.h
index bde23e1..17db3ba 100644 (file)
--- a/tools/testing/selftests/bpf/progs/bpf_iter.h
+++ b/tools/testing/selftests/bpf/progs/bpf_iter.h
@@ -9,6 +9,8 @@
 #define bpf_iter__task_file bpf_iter__task_file___not_used
 #define bpf_iter__tcp bpf_iter__tcp___not_used
 #define tcp6_sock tcp6_sock___not_used
+#define bpf_iter__udp bpf_iter__udp___not_used
+#define udp6_sock udp6_sock___not_used
 #include "vmlinux.h"
 #undef bpf_iter_meta
 #undef bpf_iter__bpf_map
@@ -18,6 +20,8 @@
 #undef bpf_iter__task_file
 #undef bpf_iter__tcp
 #undef tcp6_sock
+#undef bpf_iter__udp
+#undef udp6_sock
 
 struct bpf_iter_meta {
        struct seq_file *seq;
@@ -62,3 +66,15 @@ struct tcp6_sock {
        struct tcp_sock tcp;
        struct ipv6_pinfo inet6;
 } __attribute__((preserve_access_index));
+
+struct bpf_iter__udp {
+       struct bpf_iter_meta *meta;
+       struct udp_sock *udp_sk;
+       uid_t uid __attribute__((aligned(8)));
+       int bucket __attribute__((aligned(8)));
+} __attribute__((preserve_access_index));
+
+struct udp6_sock {
+       struct udp_sock udp;
+       struct ipv6_pinfo inet6;
+} __attribute__((preserve_access_index));

diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_udp4.c b/tools/testing/selftests/bpf/progs/bpf_iter_udp4.c
new file mode 100644 (file)
index 0000000..7053784
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_udp4.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+#include "bpf_iter.h"
+#include "bpf_tracing_net.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_endian.h>
+
+char _license[] SEC("license") = "GPL";
+
+static long sock_i_ino(const struct sock *sk)
+{
+       const struct socket *sk_socket = sk->sk_socket;
+       const struct inode *inode;
+       unsigned long ino;
+
+       if (!sk_socket)
+               return 0;
+
+       inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
+       bpf_probe_read(&ino, sizeof(ino), &inode->i_ino);
+       return ino;
+}
+
+SEC("iter/udp")
+int dump_udp4(struct bpf_iter__udp *ctx)
+{
+       struct seq_file *seq = ctx->meta->seq;
+       struct udp_sock *udp_sk = ctx->udp_sk;
+       struct inet_sock *inet;
+       __u16 srcp, destp;
+       __be32 dest, src;
+       __u32 seq_num;
+       int rqueue;
+
+       if (udp_sk == (void *)0)
+               return 0;
+
+       seq_num = ctx->meta->seq_num;
+       if (seq_num == 0)
+               BPF_SEQ_PRINTF(seq,
+                              "  sl  local_address rem_address   st tx_queue "
+                              "rx_queue tr tm->when retrnsmt   uid  timeout "
+                              "inode ref pointer drops\n");
+
+       /* filter out udp6 sockets */
+       inet = &udp_sk->inet;
+       if (inet->sk.sk_family == AF_INET6)
+               return 0;
+
+       inet = &udp_sk->inet;
+       dest = inet->inet_daddr;
+       src = inet->inet_rcv_saddr;
+       srcp = bpf_ntohs(inet->inet_sport);
+       destp = bpf_ntohs(inet->inet_dport);
+       rqueue = inet->sk.sk_rmem_alloc.counter - udp_sk->forward_deficit;
+
+       BPF_SEQ_PRINTF(seq, "%5d: %08X:%04X %08X:%04X ",
+                      ctx->bucket, src, srcp, dest, destp);
+
+       BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n",
+                      inet->sk.sk_state,
+                      inet->sk.sk_wmem_alloc.refs.counter - 1,
+                      rqueue,
+                      0, 0L, 0, ctx->uid, 0,
+                      sock_i_ino(&inet->sk),
+                      inet->sk.sk_refcnt.refs.counter, udp_sk,
+                      inet->sk.sk_drops.counter);
+
+       return 0;
+}

diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_udp6.c b/tools/testing/selftests/bpf/progs/bpf_iter_udp6.c
new file mode 100644 (file)
index 0000000..c1175a6
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_udp6.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+#include "bpf_iter.h"
+#include "bpf_tracing_net.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_endian.h>
+
+char _license[] SEC("license") = "GPL";
+
+#define IPV6_SEQ_DGRAM_HEADER                          \
+       "  sl  "                                        \
+       "local_address                         "        \
+       "remote_address                        "        \
+       "st tx_queue rx_queue tr tm->when retrnsmt"     \
+       "   uid  timeout inode ref pointer drops\n"
+
+static long sock_i_ino(const struct sock *sk)
+{
+       const struct socket *sk_socket = sk->sk_socket;
+       const struct inode *inode;
+       unsigned long ino;
+
+       if (!sk_socket)
+               return 0;
+
+       inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
+       bpf_probe_read(&ino, sizeof(ino), &inode->i_ino);
+       return ino;
+}
+
+SEC("iter/udp")
+int dump_udp6(struct bpf_iter__udp *ctx)
+{
+       struct seq_file *seq = ctx->meta->seq;
+       struct udp_sock *udp_sk = ctx->udp_sk;
+       const struct in6_addr *dest, *src;
+       struct udp6_sock *udp6_sk;
+       struct inet_sock *inet;
+       __u16 srcp, destp;
+       __u32 seq_num;
+       int rqueue;
+
+       if (udp_sk == (void *)0)
+               return 0;
+
+       seq_num = ctx->meta->seq_num;
+       if (seq_num == 0)
+               BPF_SEQ_PRINTF(seq, IPV6_SEQ_DGRAM_HEADER);
+
+       udp6_sk = bpf_skc_to_udp6_sock(udp_sk);
+       if (udp6_sk == (void *)0)
+               return 0;
+
+       inet = &udp_sk->inet;
+       srcp = bpf_ntohs(inet->inet_sport);
+       destp = bpf_ntohs(inet->inet_dport);
+       rqueue = inet->sk.sk_rmem_alloc.counter - udp_sk->forward_deficit;
+       dest  = &inet->sk.sk_v6_daddr;
+       src   = &inet->sk.sk_v6_rcv_saddr;
+
+       BPF_SEQ_PRINTF(seq, "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X ",
+                      ctx->bucket,
+                      src->s6_addr32[0], src->s6_addr32[1],
+                      src->s6_addr32[2], src->s6_addr32[3], srcp,
+                      dest->s6_addr32[0], dest->s6_addr32[1],
+                      dest->s6_addr32[2], dest->s6_addr32[3], destp);
+
+       BPF_SEQ_PRINTF(seq, "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n",
+                      inet->sk.sk_state,
+                      inet->sk.sk_wmem_alloc.refs.counter - 1,
+                      rqueue,
+                      0, 0L, 0, ctx->uid, 0,
+                      sock_i_ino(&inet->sk),
+                      inet->sk.sk_refcnt.refs.counter, udp_sk,
+                      inet->sk.sk_drops.counter);
+
+       return 0;
+}