From: Jason Xing <kernelxing@xxxxxxxxxxx> Users can write the following code to enable the bpf extension: bpf_setsockopt(skops, SOL_SOCKET, SK_BPF_CB_FLAGS, &flags, sizeof(flags)); Signed-off-by: Jason Xing <kernelxing@xxxxxxxxxxx> --- include/net/sock.h | 7 +++++++ include/uapi/linux/bpf.h | 8 ++++++++ net/core/filter.c | 22 ++++++++++++++++++++++ tools/include/uapi/linux/bpf.h | 1 + 4 files changed, 38 insertions(+) diff --git a/include/net/sock.h b/include/net/sock.h index 7464e9f9f47c..0dd464ba9e46 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -303,6 +303,7 @@ struct sk_filter; * @sk_stamp: time stamp of last packet received * @sk_stamp_seq: lock for accessing sk_stamp on 32 bit architectures only * @sk_tsflags: SO_TIMESTAMPING flags + * @sk_bpf_cb_flags: used for bpf_setsockopt * @sk_use_task_frag: allow sk_page_frag() to use current->task_frag. * Sockets that can be used under memory reclaim should * set this to false. @@ -445,6 +446,12 @@ struct sock { u32 sk_reserved_mem; int sk_forward_alloc; u32 sk_tsflags; +#ifdef CONFIG_BPF_SYSCALL +#define SK_BPF_CB_FLAG_TEST(SK, FLAG) ((SK)->sk_bpf_cb_flags & (FLAG)) + u32 sk_bpf_cb_flags; +#else +#define SK_BPF_CB_FLAG_TEST(SK, FLAG) 0 +#endif __cacheline_group_end(sock_write_rxtx); __cacheline_group_begin(sock_write_tx); diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 4162afc6b5d0..e629e09b0b31 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -6903,6 +6903,13 @@ enum { BPF_SOCK_OPS_ALL_CB_FLAGS = 0x7F, }; +/* Definitions for bpf_sk_cb_flags */ +enum { + SK_BPF_CB_TX_TIMESTAMPING = 1<<0, + SK_BPF_CB_MASK = (SK_BPF_CB_TX_TIMESTAMPING - 1) | + SK_BPF_CB_TX_TIMESTAMPING +}; + /* List of known BPF sock_ops operators. * New entries can only be added at the end */ @@ -7081,6 +7088,7 @@ enum { TCP_BPF_SYN_IP = 1006, /* Copy the IP[46] and TCP header */ TCP_BPF_SYN_MAC = 1007, /* Copy the MAC, IP[46], and TCP header */ TCP_BPF_SOCK_OPS_CB_FLAGS = 1008, /* Get or Set TCP sock ops flags */ + SK_BPF_CB_FLAGS = 1009, /* Used to set socket bpf flags */ }; enum { diff --git a/net/core/filter.c b/net/core/filter.c index 6625b3f563a4..f7e9f88e09b1 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -5214,6 +5214,24 @@ static const struct bpf_func_proto bpf_get_socket_uid_proto = { .arg1_type = ARG_PTR_TO_CTX, }; +static int sk_bpf_set_cb_flags(struct sock *sk, sockptr_t optval, bool getopt) +{ + int sk_bpf_cb_flags; + + if (getopt) + return -EINVAL; + + if (copy_from_sockptr(&sk_bpf_cb_flags, optval, sizeof(sk_bpf_cb_flags))) + return -EFAULT; + + if (sk_bpf_cb_flags & ~SK_BPF_CB_MASK) + return -EINVAL; + + sk->sk_bpf_cb_flags = sk_bpf_cb_flags; + + return 0; +} + static int sol_socket_sockopt(struct sock *sk, int optname, char *optval, int *optlen, bool getopt) @@ -5230,6 +5248,7 @@ static int sol_socket_sockopt(struct sock *sk, int optname, case SO_MAX_PACING_RATE: case SO_BINDTOIFINDEX: case SO_TXREHASH: + case SK_BPF_CB_FLAGS: if (*optlen != sizeof(int)) return -EINVAL; break; @@ -5239,6 +5258,9 @@ static int sol_socket_sockopt(struct sock *sk, int optname, return -EINVAL; } + if (optname == SK_BPF_CB_FLAGS) + return sk_bpf_set_cb_flags(sk, KERNEL_SOCKPTR(optval), getopt); + if (getopt) { if (optname == SO_BINDTODEVICE) return -EINVAL; diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 4162afc6b5d0..6b0a5b787b12 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -7081,6 +7081,7 @@ enum { TCP_BPF_SYN_IP = 1006, /* Copy the IP[46] and TCP header */ TCP_BPF_SYN_MAC = 1007, /* Copy the MAC, IP[46], and TCP header */ TCP_BPF_SOCK_OPS_CB_FLAGS = 1008, /* Get or Set TCP sock ops flags */ + SK_BPF_CB_FLAGS = 1009, /* Used to set socket bpf flags */ }; enum { -- 2.37.3