refactor: modify constant isolated iflink

takehaya · Sep 29, 2024 · 0cd8e93 · 0cd8e93
1 parent b456118
commit 0cd8e93
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Showing 3 changed files with 88 additions and 27 deletions.
diff --git a/lib/Sys/Ebpf/Link/Netlink/Constants/Iflink.pm b/lib/Sys/Ebpf/Link/Netlink/Constants/Iflink.pm
@@ -0,0 +1,50 @@
+package Sys::Ebpf::Link::Netlink::Constants::Iflink;
+
+use strict;
+use warnings;
+use utf8;
+
+use Exporter 'import';
+
+# cf. https://github.com/torvalds/linux/blob/master/include/uapi/linux/if_link.h
+my %constants = (
+
+    # IFLA_AF_SPEC section
+    'IFLA_UNSPEC' => 0,
+    'IFLA_XDP'    => 43,
+
+    # /* XDP section */
+    'XDP_FLAGS_UPDATE_IF_NOEXIST' => 1 << 0,
+    'XDP_FLAGS_SKB_MODE'          => 1 << 1,
+    'XDP_FLAGS_DRV_MODE'          => 1 << 2,
+    'XDP_FLAGS_HW_MODE'           => 1 << 3,
+    'XDP_FLAGS_REPLACE'           => 1 << 4,
+    'XDP_FLAGS_MODES'             => ( 1 << 1 | 1 << 2 | 1 << 3 ),
+    'XDP_FLAGS_MASK'       => ( 1 << 0 | 1 << 1 | 1 << 2 | 1 << 3 | 1 << 4 ),
+    'XDP_ATTACHED_NONE'    => 0,
+    'XDP_ATTACHED_DRV'     => 1,
+    'XDP_ATTACHED_SKB'     => 2,
+    'XDP_ATTACHED_HW'      => 3,
+    'XDP_ATTACHED_MULTI'   => 4,
+    'IFLA_XDP_UNSPEC'      => 0,
+    'IFLA_XDP_FD'          => 1,
+    'IFLA_XDP_ATTACHED'    => 2,
+    'IFLA_XDP_FLAGS'       => 3,
+    'IFLA_XDP_PROG_ID'     => 4,
+    'IFLA_XDP_DRV_PROG_ID' => 5,
+    'IFLA_XDP_SKB_PROG_ID' => 6,
+    'IFLA_XDP_HW_PROG_ID'  => 7,
+    'IFLA_XDP_EXPECTED_FD' => 8,
+);
+
+# Export all constants
+our @EXPORT_OK   = keys %constants;
+our %EXPORT_TAGS = ( all => \@EXPORT_OK );
+
+# Define constants as subroutines
+for my $name (@EXPORT_OK) {
+    no strict 'refs';
+    *{$name} = sub () { $constants{$name} };
+}
+
+1;
diff --git a/lib/Sys/Ebpf/Link/Netlink/Socket.pm b/lib/Sys/Ebpf/Link/Netlink/Socket.pm
@@ -6,7 +6,6 @@ use Socket qw( SOCK_RAW );
 use Errno  ();
 use Exporter 'import';
 
-# エクスポートする関数をリストに追加
 our @EXPORT_OK
     = qw(pack_sockaddr_nl pack_nlattr pack_nlmsghdr pack_ifinfomsg);
 
@@ -49,9 +48,8 @@ sub send_message {
     my ( $self, $message ) = @_;
 
     # カーネル（pid 0）にメッセージを送信
-    my $sockaddr_nl = pack_sockaddr_nl(0);     # pid=0（カーネル）
-
-    my $bytes_sent = send( $self->{sock}, $message, 0, $sockaddr_nl );
+    my $sockaddr_nl = pack_sockaddr_nl(0);
+    my $bytes_sent  = send( $self->{sock}, $message, 0, $sockaddr_nl );
     unless ($bytes_sent) {
         die "Failed to send Netlink message: $!";
     }
@@ -77,15 +75,19 @@ sub close {
     close( $self->{sock} ) if $self->{sock};
 }
 
-# ヘルパー関数
-
-# sockaddr_nlをパック
+# cf. https://github.com/torvalds/linux/blob/3efc57369a0ce8f76bf0804f7e673982384e4ac9/include/uapi/linux/netlink.h#L37
+# typedef unsigned short __kernel_sa_family_t;
+# struct sockaddr_nl {
+# 	__kernel_sa_family_t	nl_family;	/* AF_NETLINK	*/
+# 	unsigned short	nl_pad;		/* zero		*/
+# 	__u32		nl_pid;		/* port ID	*/
+#   __u32		nl_groups;	/* multicast groups mask */
+# };
 sub pack_sockaddr_nl {
     my ($pid) = @_;
     return pack( 'S x2 L L', AF_NETLINK, $pid, 0 );
 }
 
-# Netlink属性をパック
 # cf. https://github.com/torvalds/linux/blob/3efc57369a0ce8f76bf0804f7e673982384e4ac9/include/uapi/linux/netlink.h#L229
 # /*
 #  *  <------- NLA_HDRLEN ------> <-- NLA_ALIGN(payload)-->
@@ -105,12 +107,11 @@ sub pack_nlattr {
     my $nla_padded_len = ( $nla_len + 3 ) & ~3;            # 4バイト境界にアライン
     my $padding        = "\0" x ( $nla_padded_len - $nla_len );    # パディング
     return
-          pack( 'S< S<', $nla_padded_len, $type )
+          pack( 'S S', $nla_padded_len, $type )
         . $payload
         . $padding;    # パディング後の長さでパック
 }
 
-# Netlinkメッセージヘッダーをパック
 # cf. https://github.com/torvalds/linux/blob/3efc57369a0ce8f76bf0804f7e673982384e4ac9/include/uapi/linux/netlink.h#L52
 # /**
 #  * struct nlmsghdr - fixed format metadata header of Netlink messages
@@ -132,7 +133,15 @@ sub pack_nlmsghdr {
     return pack( 'L S S L L', $len, $type, $flags, $seq, $pid );
 }
 
-# ifinfomsgをパック
+# cf. https://github.com/torvalds/linux/blob/3efc57369a0ce8f76bf0804f7e673982384e4ac9/include/uapi/linux/rtnetlink.h#L561
+# struct ifinfomsg {
+# 	unsigned char	ifi_family;
+# 	unsigned char	__ifi_pad;
+# 	unsigned short	ifi_type;		/* ARPHRD_* */
+# 	int		ifi_index;		/* Link index	*/
+# 	unsigned	ifi_flags;		/* IFF_* flags	*/
+# 	unsigned	ifi_change;		/* IFF_* change mask */
+# };
 sub pack_ifinfomsg {
     my ( $family, $type, $index, $flags, $change ) = @_;
     return pack( 'C C S I I I', $family, 0, $type, $index, $flags, $change );

diff --git a/lib/Sys/Ebpf/Link/Netlink/Xdp.pm b/lib/Sys/Ebpf/Link/Netlink/Xdp.pm
@@ -4,27 +4,29 @@ use strict;
 use warnings;
 use IO::Interface::Simple ();
 use Sys::Ebpf::Link::Netlink::Socket;
+use Sys::Ebpf::Link::Netlink::Constants::Iflink qw(
+    IFLA_XDP
+    IFLA_XDP_FD
+    IFLA_XDP_ATTACHED
+    IFLA_XDP_FLAGS
+    XDP_FLAGS_UPDATE_IF_NOEXIST
+    XDP_FLAGS_SKB_MODE
+    XDP_FLAGS_DRV_MODE
+);
 use Socket qw( AF_UNSPEC );
 use Errno  ();
 
 # 定数の定義
 use constant {
-    RTM_SETLINK                 => 19,
-    IFLA_XDP                    => 43,
-    IFLA_XDP_FD                 => 1,
-    IFLA_XDP_ATTACHED           => 2,
-    IFLA_XDP_FLAGS              => 3,
-    NLA_F_NESTED                => 0x8000,
-    XDP_FLAGS_UPDATE_IF_NOEXIST => 1 << 0,
-    XDP_FLAGS_SKB_MODE          => 1 << 1,
-    XDP_FLAGS_DRV_MODE          => 1 << 2,
-    NLM_F_REQUEST               => 0x0001,
-    NLM_F_ACK                   => 0x0004,
-    NLMSG_HDRLEN                => 16,
-    NLA_HDRLEN                  => 4,
-    NETLINK_ROUTE               => 0,        # NETLINK_ROUTEの定義
-    NLMSG_ERROR                 => 2,        # NLMSG_ERRORの定義
-    IFF_UP                      => 1 << 0,
+    RTM_SETLINK   => 19,
+    NLA_F_NESTED  => 0x8000,
+    NLM_F_REQUEST => 0x0001,
+    NLM_F_ACK     => 0x0004,
+    NLMSG_HDRLEN  => 16,
+    NLA_HDRLEN    => 4,
+    NETLINK_ROUTE => 0,        # NETLINK_ROUTEの定義
+    NLMSG_ERROR   => 2,        # NLMSG_ERRORの定義
+    IFF_UP        => 1 << 0,
 };
 
 # ヘルパー関数をインポート