ssh - SSH2 算法协商数据包有效负载中的名称列表如何分开？

Question

我在 RFC4253 中找到那:

7.1. Algorithm Negotiation

Key exchange begins by each side sending the following packet:

  byte         SSH_MSG_KEXINIT
  byte[16]     cookie (random bytes)
  name-list    kex_algorithms
  name-list    server_host_key_algorithms
  name-list    encryption_algorithms_client_to_server
  name-list    encryption_algorithms_server_to_client
  name-list    mac_algorithms_client_to_server
  name-list    mac_algorithms_server_to_client
  name-list    compression_algorithms_client_to_server
  name-list    compression_algorithms_server_to_client
  name-list    languages_client_to_server
  name-list    languages_server_to_client
  boolean      first_kex_packet_follows
  uint32       0 (reserved for future extension)

Each of the algorithm name-lists MUST be a comma-separated list ofalgorithm names (see Algorithm Naming in [SSH-ARCH] and additional
information in [SSH-NUMBERS]). Each supported (allowed) algorithm
MUST be listed in order of preference, from most to least.

但是我在 RFC 中找不到关于如何在有效负载中分隔名称列表的信息。
编辑:
全部通过 DataInputStream 解决, 使用方便的方法 readByte(byte[] b, int off, int len) , readInt()和 readBoolean() .

Answer 1

正如 RFC 所述，SSH-ARCH 中有更多信息。这是RFC 4251 .以下是 name-list 的部分摘录被定义为:

A string containing a comma-separated list of names. A name-list isrepresented as a uint32 containing its length (number of bytes thatfollow) followed by a comma-separated list of zero or more names.

因此，在您读取了 key 交换数据包的前 17 个字节后，您将需要读取 4 个字节，这将告诉您需要读取多少字节(它是 ASCII 编码的，因此每个字符 1 个字节)以消耗其余部分 name-list .然后为每个后续列表重复此过程。