sshd 如何知道调用 shell？

Question

当我输入时ssh remote-host command，将为我sshd运行。bash -c command

如何知道用选项sshd来调用？bash-c

Answer 1

哦，该死，这是在 OpenSSH 源代码中硬编码的。

来自OpenSSH 5.9p1源代码的session.c：

/*
 * Execute the command using the user's shell.  This uses the -c
 * option to execute the command.
 */
argv[0] = (char *) shell0;
argv[1] = "-c";
argv[2] = (char *) command;
argv[3] = NULL;
execve(shell, argv, env);
perror(shell);
exit(1);

所以我猜这是一个 POSIX 标准吧？