「ICMPv6」- 报文格式

0

在 IPv6 Header 中，当 Next-Header == 58 时，则对应为 ICMPv6 报文。

报文格式

Type：表明消息的类型。ICMPv6 报文载荷由 ICMPv6 报文 Type 字段决定，因报文类型的不同而不同。

Code：表示消息类型的细分。

Checksum：表示 ICMPv6 报文的校验和。

Message Body：报文内容。对于 ping 报文，其中包含随机数据；对于类型为 NS NA RS RA 的报文，其中包含结构化的数据和相关信息。

报文示例

ICMPv6 Request and ICMPv6 Reply

Request

Frame 14: 118 bytes on wire (944 bits), 118 bytes captured (944 bits) on interface -, id 0
Ethernet II, Src: 38:39:cc:01:01:00 (38:39:cc:01:01:00), Dst: 38:39:cc:02:01:00 (38:39:cc:02:01:00)
Internet Protocol Version 6, Src: 2000:12::1, Dst: 2000:12::2
    0110 .... = Version: 6
    .... 0000 0000 .... .... .... .... .... = Traffic Class: 0x00 (DSCP: CS0, ECN: Not-ECT)
        .... 0000 00.. .... .... .... .... .... = Differentiated Services Codepoint: Default (0)
        .... .... ..00 .... .... .... .... .... = Explicit Congestion Notification: Not ECN-Capable Transport (0)
    .... 0000 0000 0000 0000 0000 = Flow Label: 0x00000
    Payload Length: 64
    Next Header: ICMPv6 (58)
    Hop Limit: 64
    Source Address: 2000:12::1
        [Address Space: Global Unicast]
    Destination Address: 2000:12::2
        [Address Space: Global Unicast]
    [Stream index: 0]
Internet Control Message Protocol v6
    Type: Echo (ping) request (128)
    Code: 0
    Checksum: 0x82fb [correct]
    [Checksum Status: Good]
    Identifier: 0x2400
    Sequence: 256
    [Response In: 15]
    Data (56 bytes)
        Data: 001100000101ff01504e47000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
        [Length: 56]

Reply

Frame 15: 118 bytes on wire (944 bits), 118 bytes captured (944 bits) on interface -, id 0
Ethernet II, Src: 38:39:cc:02:01:00 (38:39:cc:02:01:00), Dst: 38:39:cc:01:01:00 (38:39:cc:01:01:00)
Internet Protocol Version 6, Src: 2000:12::2, Dst: 2000:12::1
    0110 .... = Version: 6
    .... 0000 0000 .... .... .... .... .... = Traffic Class: 0x00 (DSCP: CS0, ECN: Not-ECT)
        .... 0000 00.. .... .... .... .... .... = Differentiated Services Codepoint: Default (0)
        .... .... ..00 .... .... .... .... .... = Explicit Congestion Notification: Not ECN-Capable Transport (0)
    .... 0000 0000 0000 0000 0000 = Flow Label: 0x00000
    Payload Length: 64
    Next Header: ICMPv6 (58)
    Hop Limit: 64
    Source Address: 2000:12::2
        [Address Space: Global Unicast]
    Destination Address: 2000:12::1
        [Address Space: Global Unicast]
    [Stream index: 0]
Internet Control Message Protocol v6
    Type: Echo (ping) reply (129)
    Code: 0
    Checksum: 0x81fb [correct]
    [Checksum Status: Good]
    Identifier: 0x2400
    Sequence: 256
    [Response To: 14]
    [Response Time: 0.000 ms]
    Data (56 bytes)
        Data: 001100000101ff01504e47000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
        [Length: 56]