new_gate/ms-runner
4
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

initial commit

Browse source
This commit is contained in:
root 2024-06-20 21:41:25 +05:00
commit 24ff954904
9 changed files with 419 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

16
Makefile Normal file
View file

@ -0,0 +1,16 @@
all:
rm -rf starter/alpine-make-rootfs
git clone https://github.com/alpinelinux/alpine-make-rootfs
mv alpine-make-rootfs starter/alpine-make-rootfs
go build -o ./run
gcc starter/starter.c -o starter/starter
starter/create_rootfs.sh
install_minrootfs:
rm -rf starter/alpine-make-rootfs
git clone https://github.com/alpinelinux/alpine-make-rootfs
mv alpine-make-rootfs starter/alpine-make-rootfs
mkrootfs:
starter/create_rootfs.sh
compile:
go build -o ./run
gcc starter/starter.c -o starter/starter

17
main.go Normal file
View file

@ -0,0 +1,17 @@
package main
import (
//"os"
//"fmt"
//"log"
//exec "os/exec"
runner "runner/runner"
)
func main() {
err:=runner.Init()
if(err!=nil) {
panic(err)
}
//runner.IsolatedRun(exec.Command("ls", "/"))
}

89
runner/runner.go Normal file
View file

@ -0,0 +1,89 @@
package runner
import (
"errors"
"fmt"
"log"
"os"
"strings"
exec "os/exec"
cgroups "github.com/containerd/cgroups"
//cgroup2 "github.com/containerd/cgroups/v3/cgroup2"
//specs "github.com/opencontainers/runtime-spec/specs-go"
rand "math/rand"
"time"
"os/user"
)
const runner_username string = "gaterunner"
const runIdLength = 20
var coresIsolated []int
type Limits {
core int
memory int
}
func extractNumbers(s string) (result []int) {
lastNumber,isNumber := false,false
var curNumber=0
for _,char :=range s {
isNumber=(char>='0' && char<='9')
if(isNumber) {
curNumber*=10
curNumber+=int(char-'0')
}
if(!isNumber && lastNumber) {
result=append(result,curNumber)
curNumber=0
}
lastNumber=isNumber
}
if(lastNumber) {
result=append(result,curNumber)
}
return
}
func Init() error {
rand.Seed(time.Now().UnixNano())
//croup initialisation:
if cgroups.Mode() == cgroups.Unified {
log.Println("cgroups v2 usage approved")
} else {
return fmt.Errorf("cgroups v2 are not enabled")//TODO: trouble description
}
//isolated cores initialisation:
cmdlineBytes := make([]byte, 400)
cmdlineFile,_:=os.Open("/proc/cmdline");
countCmdlineBytes,_:=cmdlineFile.Read(cmdlineBytes);
cmdline:=string(cmdlineBytes[:countCmdlineBytes])
kernelParams:=strings.Split(cmdline," ")
for _,param := range kernelParams{
if(len(param)>=9 && param[:9]=="isolcpus=") {
coresIsolated=append(coresIsolated, extractNumbers(param[9:])...)
}
}
if(len(coresIsolated)==0) {
return fmt.Errorf("no free cores available")//TODO: trouble description
}
log.Println("running on cores:",coresIsolated)
//user setup:
_,err:=user.Lookup(runner_username)
if err!=nil{
if errors.As(err, new(user.UnknownUserError)) {
exec.Command("useradd", runner_username).Run();
} else {
return fmt.Errorf("user error:",err)
}
}
log.Println("Runner initialisation successful!")
return nil
}
func IsolatedRun(command []string,core int) {
var runId string
for i:=0;i<runIdLength;i++{
runId+=string('a'+byte(rand.Int31n(26)))
}
}

32
runner/runner_test.go Normal file
View file

@ -0,0 +1,32 @@
package runner
import (
"testing"
)
type ENTestPair struct {
test string
result []int
}
var ENTests = []ENTestPair {
{"123",[]int{123}},
{"abc123abc",[]int{123}},
{"",[]int{}},
{"0",[]int{0}},
{"1a2a3a6",[]int{1,2,3,6}},
}
func TestExtractNumbers(t *testing.T) {
for _,test:=range(ENTests) {
result:=extractNumbers(test.test)
if(len(result)!=len(test.result)) {
t.Error("for",test.test,"expected",test.result,"got",result)
}
for i:=0;i<len(result);i++ {
if(result[i]!=test.result[i]) {
t.Error("for",test.test,"expected",test.result,"got",result)
}
}
}
}

51
starter/cgroup_prepare.c Normal file
View file

@ -0,0 +1,51 @@
#include<sys/prctl.h>
#include<sys/mount.h>
#include<sys/stat.h>
#include<unistd.h>
#include<linux/limits.h>
#define CGROUP_NAME_SIZE 20
char cgroup_name[CGROUP_NAME_SIZE+1];
const char* cgroups_path="/sys/fs/cgroup/";
void prepare_cgroup(struct limits* limits) {
for(int i=0;i<CGROUP_NAME_SIZE;i++) {
cgroup_name[i]='a'+rand()%26;
}
char cwd[PATH_MAX];
if(getcwd(cwd,sizeof(cwd))==NULL) die("getcwd error: %m");
chdir(cgroups_path);
mkdir(cgroup_name,0755);
chdir(cgroup_name);
char* memory_string=NULL;
asprintf(&memory_string,"%d\n",limits->memory);
write_file("memory.max",memory_string);
free(memory_string);
char* cpus_string=NULL;
asprintf(&cpus_string,"%d\n",limits->core);
write_file("cpuset.cpus",cpus_string);
free(cpus_string);
write_file("pids.max","1\n");
//write_file("cpuset.cpus","3\n");
chdir(cwd);
}
void add_to_cgroup(int pid) {
char cwd[PATH_MAX];
if(getcwd(cwd,sizeof(cwd))==NULL) die("getcwd error: %m");
chdir(cgroups_path);
chdir(cgroup_name);
char* pidstr=NULL;
asprintf(&pidstr,"%d\n",pid);
write_file("cgroup.procs",pidstr);
free(pidstr);
chdir(cwd);
}
void remove_cgroup() {
char cwd[PATH_MAX];
if(getcwd(cwd,sizeof(cwd))==NULL) die("getcwd error: %m");
if(chdir(cgroups_path)) die("chdir error: %m");
if(rmdir(cgroup_name)) die("rmdir error: %m");
if(chdir(cwd)) die("chdir error: %m");
}

17
starter/create_rootfs.sh Executable file
View file

@ -0,0 +1,17 @@
#!/bin/bash
if [[ $(whoami) != root ]]
then
echo "run as root please"
exit
fi
NAME=minrootfs
SCRIPT_DIR=$(dirname -- "$(readlink -f "${BASH_SOURCE}")")
rm -rf $SCRIPT_DIR/$NAME
sudo $SCRIPT_DIR/alpine-make-rootfs/alpine-make-rootfs $SCRIPT_DIR/$NAME
#chown -R nobody:nogroup $SCRIPT_DIR/$NAME
#rm -r ../$NAME
#mv $NAME ../$NAME

77
starter/ns_exec.c Normal file
View file

@ -0,0 +1,77 @@
#include<sys/prctl.h>
#include<sys/mount.h>
#include<sys/stat.h>
static void procfs_prepare()
{
if (mkdir("/proc", 0555) && errno != EEXIST) die("Failed to mkdir /proc: %m\n");
if (mount("proc", "/proc", "proc", 0, "")) die("Failed to mount proc: %m\n");
}
#define hostname "runner"
#define put_old "oldfs"
//#define shared_folder "../shared"
//#define shared_mountpoint "shared"
void mnt_prepare(char* rootfs, char* shared_mountpoint) {
//char* shared_folder = malloc(strlen(shared_mountpoint)+4);
//strcpy(shared_folder,"../");
//strcat(shared_folder,shared_mountpoint);
char* shared_folder=NULL;
asprintf(&shared_folder,"../%s",shared_mountpoint);
if (mount(rootfs,rootfs,"ext4",MS_BIND,"")) die("failed to mount %s: %m", rootfs);
//if (mount(shared_mountpoint,shared_mountpoint,"ext4",MS_BIND,"")) die("failed to mount %s: %m",shared_mountpoint);
if (chdir(rootfs)) die("falied to cd:%m");
if (mount("/sys","sys","sysfs",0,"")) die("failed to mount: %m");
//if (mount("/dev","dev","udev",0,"")) die("failed to mount: %m");
if (mkdir("shared", 0777) && errno != EEXIST) die("Failed to mkdir %s: %m\n", shared_mountpoint);
if (mount(shared_folder,"shared","ext4",MS_BIND,"")) die("failed to mount: %m");
if (mkdir(put_old, 0000) && errno != EEXIST) die("Failed to mkdir %s: %m\n", put_old);
if (syscall(SYS_pivot_root, ".", put_old)) die("Failed to pivot_root from %s to %s: %m\n", rootfs, put_old);
if (chdir("/")) die("Failed to chdir to new root: %m\n");
procfs_prepare();
if (umount2(put_old, MNT_DETACH)) die("Failed to umount put_old %s: %m\n", put_old);
if (rmdir(put_old)) die("Failed to rmdir: %m");
free(shared_folder);
}
void ro_fs(char* shared_mountpoint) {
char* shared_folder = malloc(strlen(shared_mountpoint)+4);
strcpy(shared_folder,"../");
strcat(shared_folder,shared_mountpoint);
if (mount("/","/","ext4",MS_REMOUNT | MS_RDONLY | MS_BIND,"")) die("failed to mount: %m");
if (mount(shared_mountpoint,"shared","ext4",MS_REMOUNT | MS_RDONLY | MS_BIND,"")) die("failed to mount: %m");
free(shared_folder);
}
//#undef shared_mountpoint
//#undef shared_folder
#undef put_old
void await_setup(int pipe) { // wait for signal from parent
char buf[2];
if (read(pipe, buf, 2) != 2) die("Failed to read from pipe: %m\n");
}
static int nsrun(void* arg) {
#define setup "./setup.sh"
//die when parent dies
if (prctl(PR_SET_PDEATHSIG, SIGKILL)) die("cannot PR_SET_PDEATHSIG for child process: %m\n");
struct params *params = (struct params*) arg;
await_setup(params->fd[0]);
mnt_prepare("minrootfs",params->shared_folder);
//if(chdir("shared")) die("faled to chdir: %m");
sethostname(hostname,sizeof(hostname));
//if(chdir("..")) die("faled to chdir: %m");
ro_fs(params->shared_folder);
if(setgid(1000)) die("failed to setgid:%m");
if(setuid(1000)) die("failed to setuid:%m");
char** argv = params->argv;
char* cmd = argv[0];
char* env[]={
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
"PWD=/",
"NULL",
};
if (execve(cmd,argv,env) == -1) die("failed to exec,%m");
return 1;
#undef setup
}

98
starter/starter.c Normal file
View file

@ -0,0 +1,98 @@
#define _GNU_SOURCE
#include <sys/wait.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sched.h>
#include <sys/syscall.h>
#include <linux/sched.h>
#include <stdarg.h>
#include <time.h>
#include "util.h"
struct params {
char* shared_folder;
int fd[2];
char **argv;
};
struct limits {
size_t memory;
int core;
};
#include "ns_exec.c"
#include "cgroup_prepare.c"
//const size_t STACK_SIZE=1000000;
#define STACK_SIZE 1000000
static char nmstack[STACK_SIZE];
static void parse_args(int argc, char **argv, struct params *params,struct limits *limits){
if (argc < 5) {
printf("usage:\n starter <core_id> <memory_amount> <shared folder> <command, arg1,arg2,...>");
exit(0);
}
argc--;argv++;
limits->core=atoi(argv[0]);
argc--;argv++;
limits->memory=atoi(argv[0]);
argc--;argv++;
params->shared_folder=argv[0];
argc--;argv++;
params->argv = argv;
}
static void prepare_userns(int pid) {
char path[100];
char line[100];
int uid = getuid();
int gid = getgid();
//int unprivileged_uid=1002;
//int unprivileged_gid=1002;
int unprivileged_uid=66534;
int unprivileged_gid=65534;
sprintf(path, "/proc/%d/uid_map", pid);
sprintf(line, "0 %d 1\n1 %d 1000\n", uid, unprivileged_uid);
write_file(path, line);
sprintf(path, "/proc/%d/setgroups", pid);
sprintf(line, "deny");
write_file(path, line);
sprintf(path, "/proc/%d/gid_map", pid);
sprintf(line, "0 %d 1\n1 %d 1000\n", gid, unprivileged_gid);
write_file(path, line);
}
int main(int argc,char** argv) {
srand(time(NULL));
struct params params;
memset(&params, 0, sizeof(struct params));
struct limits limits;
memset(&limits, 0, sizeof(struct limits));
parse_args(argc, argv, &params, &limits);
prepare_cgroup(&limits);
//exit(0);
if(setuid(0)) die("need to be run as root");
if(setgid(0)) die("need to be run as root");
if (pipe(params.fd) < 0) exit(0);
int clone_flags = SIGCHLD | CLONE_NEWUTS | CLONE_NEWUSER | CLONE_NEWNS | CLONE_NEWPID | CLONE_NEWNET | CLONE_NEWIPC | CLONE_NEWCGROUP/* | CLONE_NEWTIME*/;
int nsrun_pid=clone(nsrun,nmstack+STACK_SIZE,clone_flags,&params);
int pipe=params.fd[1];
//sleep(1);
prepare_userns(nsrun_pid);
if (nsrun_pid<0) {die("faled to clone");}
add_to_cgroup(nsrun_pid);
if (write(pipe, "OK", 2) != 2) die("Failed to write to pipe: %m");//report readiness
if (waitpid(nsrun_pid, NULL, 0) == -1) die("Failed to wait pid %d: %m\n", nsrun_pid);
//int pipe=params.fd[1];
remove_cgroup();
return 0;
}

22
starter/util.h Normal file
View file

@ -0,0 +1,22 @@
//#ifndef ISOLATE_UTIL_H
//#define ISOLATE_UTIL_H
static void die(const char *fmt, ...)
{
va_list params;
va_start(params, fmt);
vfprintf(stderr, fmt, params);
va_end(params);
exit(1);
}
static void write_file(char* path, char* line)
{
FILE *f = fopen(path, "w");
if (f == NULL) {die("Failed to open file %s: %m\n", path);}
if (fwrite(line, 1, strlen(line), f) < 0) {die("Failed to write to file %s:\n", path);}
if (fclose(f) != 0) {die("Failed to close file %s: %m\n", path);}
}
//#endif //ISOLATE_UTIL_H