从 php 中的命令获取所有 bash 子 shell

Question

我需要检测一个命令在其子命令之一中是否有 sudo 命令，到目前为止我有这个：

public function split_command($command) {
    // this regex is not perfect but work
    $separators = "/(?:\"[^\"\\]*(?:\\[\S\s][^\"\\]*)*\"|'[^'\\]*(?:\\[\S\s][^'\\]*)*')(*SKIP)(*F)|(\s+(?:&&|\|{1,2}|;)\s+)/";
    $flags = PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE;
    return preg_split($separators, $command, null, $flags);
}
public function have_sudo($command) {
    $re = "!^(sudo|" . shell_exec("which sudo") . ")!";
    foreach ($this->split_command($command) as $part) {
        if (preg_match($re, trim($part))) {
            return true;
        }
    }
}

但如果失败，命令如下所示：echo `sudo whoami`。如何解析命令以获取子 shell 列表。

它也应该适用于这样的命令：

$(some command; `other command (different command) $(some command)`)

应该return数组：

["some command; `other command (different command) $(some command)`",
 "`other command (different command) $(some command)",
 "different command", "some command"]

所以我可以在数组的每个元素上递归调用 have_sudo 另一个选项是 return 来自命令的最外层子 shell。

Answer 1

我已经创建了一个解析器：

public function get_subshells($command) {
    $re = '/($\(|\(|\)|`)/';
    $parts = preg_split($re, $command, -1, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY);
    $subshells = array();
    $backtick = false;
    $stack = array();
    foreach ($parts as $part) {
        if (preg_match($re, $part)) {
            if ($part == "`") {
                $backtick = !$backtick;
            }
            if ($backtick || preg_match("/\(/", $part)) {
                $stack[] = array('tag' => $part, 'content' => '');
            } else {
                $last = array_pop($stack);
                $subshells[] = preg_replace('/^($\(|\(|`)/', '', $last['content']);
            }
        }
        if (count($stack) > 0) {
            foreach ($stack as &$subshell) {
                $subshell['content'] .= $part;
            }
        }

    }
    return array_reverse($subshells);
}

从 php 中的命令获取所有 bash 子 shell

Get all bash subshells from command in php

php

bash

parsing

sudo