Magisk/native/jni/su/connect.cpp

/*
** Copyright 2018, John Wu (@topjohnwu)
** Copyright 2010, Adam Shanks (@ChainsDD)
** Copyright 2008, Zinx Verituse (@zinxv)
**
*/

#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdlib.h>
#include <fcntl.h>
#include <stdio.h>

#include <magisk.h>
#include <daemon.h>
#include <utils.h>

#include "su.h"

#define BROADCAST_BOOT_COMPLETED \
"/system/bin/app_process", "/system/bin", "com.android.commands.am.Am", \
"broadcast", nullptr, nullptr, "-a", "android.intent.action.BOOT_COMPLETED", \
"-f", "0x00000020"

static inline const char *get_command(const struct su_request *to) {
	if (to->command[0])
		return to->command;
	if (to->shell[0])
		return to->shell;
	return DEFAULT_SHELL;
}

static void silent_run(const char **args, struct su_info *info) {
	char component[128];
	if (SDK_INT >= 22) {
		args[4] = "-p";
		args[5] = info->str[SU_MANAGER];
	} else {
		sprintf(component, "%s/a.h", info->str[SU_MANAGER]);
		args[4] = "-n";
		args[5] = component;
	}
	exec_t exec {
		.pre_exec = []() -> void {
			int null = xopen("/dev/null", O_WRONLY | O_CLOEXEC);
			dup2(null, STDOUT_FILENO);
			dup2(null, STDERR_FILENO);
			setenv("CLASSPATH", "/system/framework/am.jar", 1);
		},
		.fork = fork_dont_care,
		.argv = args
	};
	exec_command(exec);
}

static void setup_user(char *user, struct su_info *info) {
	switch (info->cfg[SU_MULTIUSER_MODE]) {
		case MULTIUSER_MODE_OWNER_ONLY:
		case MULTIUSER_MODE_OWNER_MANAGED:
			sprintf(user, "%d", 0);
			break;
		case MULTIUSER_MODE_USER:
			sprintf(user, "%d", info->uid / 100000);
			break;
	}
}

void app_log(struct su_context *ctx) {
	char user[8];
	setup_user(user, ctx->info);

	char fromUid[8];
	sprintf(fromUid, "%d",
			ctx->info->cfg[SU_MULTIUSER_MODE] == MULTIUSER_MODE_OWNER_MANAGED ?
			ctx->info->uid % 100000 : ctx->info->uid);

	char toUid[8];
	sprintf(toUid, "%d", ctx->req.uid);

	char pid[8];
	sprintf(pid, "%d", ctx->pid);

	char policy[2];
	sprintf(policy, "%d", ctx->info->access.policy);

	const char *cmd[] = {
		BROADCAST_BOOT_COMPLETED,
		"--user", user,
		"--es", "action", "log",
		"--ei", "from.uid", fromUid,
		"--ei", "to.uid", toUid,
		"--ei", "pid", pid,
		"--ei", "policy", policy,
		"--es", "command", get_command(&ctx->req),
		"--ez", "notify", ctx->info->access.notify ? "true" : "false",
		nullptr
	};
	silent_run(cmd, ctx->info);
}

void app_notify(struct su_context *ctx) {
	char user[8];
	setup_user(user, ctx->info);

	char fromUid[8];
	sprintf(fromUid, "%d",
			ctx->info->cfg[SU_MULTIUSER_MODE] == MULTIUSER_MODE_OWNER_MANAGED ?
			ctx->info->uid % 100000 : ctx->info->uid);

	char policy[2];
	sprintf(policy, "%d", ctx->info->access.policy);

	const char *cmd[] = {
		BROADCAST_BOOT_COMPLETED,
		"--user", user,
		"--es", "action", "notify",
		"--ei", "from.uid", fromUid,
		"--ei", "policy", policy,
		nullptr
	};
	silent_run(cmd, ctx->info);
}

void app_connect(const char *socket, struct su_info *info) {
	char user[8];
	setup_user(user, info);

	const char *cmd[] = {
		BROADCAST_BOOT_COMPLETED,
		"--user", user,
		"--es", "action", "request",
		"--es", "socket", socket,
		nullptr
	};
	silent_run(cmd, info);
}

void socket_send_request(int fd, struct su_info *info) {
	write_key_token(fd, "uid", info->uid);
	write_string_be(fd, "eof");
}