[CRIU] [PATCH 4/4] service: add check request support

[Pavel Emelyanov]

On 11/16/2013 05:00 AM, Ruslan Kuprieiev wrote:


Write comment about what this request checks as if you were writing a
documentation for it.

> Signed-off-by: Ruslan Kuprieiev <kupruser at gmail.com>
> ---
>  cr-service.c | 116 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 116 insertions(+)
> 
> diff --git a/cr-service.c b/cr-service.c
> index 65710fd..c2e4a3e 100644
> --- a/cr-service.c
> +++ b/cr-service.c
> @@ -12,12 +12,16 @@
>  #include <sys/un.h>
>  #include <sys/wait.h>
>  #include <sys/stat.h>
> +#include <fcntl.h>
>  
>  #include "crtools.h"
>  #include "cr_options.h"
>  #include "util.h"
>  #include "log.h"
>  #include "pstree.h"
> +#include "proc_parse.h"
> +#include "protobuf.h"
> +#include "protobuf/creds.pb-c.h"
>  #include "cr-service.h"
>  
>  unsigned int service_sk_ino = -1;
> @@ -217,6 +221,116 @@ exit:
>  	return success ? 0 : 1;
>  }
>  
> +static int can_dump(int pid)
> +{
> +	struct proc_status_creds creds;
> +	int ret;
> +
> +	ret = parse_pid_status(pid, &creds);
> +	if (ret < 0) {
> +		pr_perror("Can't get task stat");
> +		return -1;
> +	}
> +
> +	if (!may_dump(&creds)) {
> +		pr_perror("Have no rights to dump task %d", pid);
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
> +static int can_restore(void)
> +{
> +	char path[PATH_MAX];
> +	struct stat s;
> +	CredsEntry *ce;
> +	int fd;
> +
> +	if (check_img_inventory() < 0) {
> +		pr_perror("Something wrong with images");
> +		return -1;
> +	}
> +
> +	if (prepare_task_entries()) {
> +		pr_perror("Can't prepare task ent");
> +		return -1;
> +	}
> +
> +	if (read_pstree_image()) {
> +		pr_perror("Can't read pstree image");
> +		return -1;
> +	}
> +
> +	sprintf(path, "/proc/%d", root_item->pid.real);
> +	if (stat(path, &s)) {
> +		if (errno != ENOENT)
> +			return -1;
> +	} else {
> +		pr_perror("Process %d exists", root_item->pid.real);
> +		return -1;
> +	}
> +
> +	fd = open_image(CR_FD_CREDS, O_RSTR, root_item->pid.virt);
> +	if (fd < 0)
> +		return -1;
> +
> +	if (pb_read_one(fd, &ce, PB_CREDS) < 0)
> +		return -1;
> +
> +	close_safe(&fd);
> +
> +	if (!may_restore(ce)) {
> +		pr_perror("Have no rights to restore task");
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
> +static int check_using_req(int sk, CriuOpts *req)
> +{
> +	bool success = false;
> +	CriuResp msg = CRIU_RESP__INIT;
> +	CriuCheckResp resp = CRIU_CHECK_RESP__INIT;
> +
> +	if (setup_opts_from_req(sk, req) == -1) {
> +		pr_perror("Arguments treating fail");
> +		goto exit;
> +	}
> +
> +	resp.kernel = true;
> +	if (cr_check()) {
> +		pr_perror("The kernel support isn't up-to-date");
> +		resp.kernel = false;
> +	}
> +
> +	resp.dump = true;
> +	if (can_dump(req->pid)) {
> +		pr_perror("Can't dump process %d", req->pid);
> +		resp.dump = false;
> +	}
> +
> +	resp.restore = true;
> +	if (can_restore()) {
> +		pr_perror("Can't restore process");
> +		resp.restore = false;
> +	}
> +
> +	success = true;
> +exit:
> +	msg.type = CRIU_REQ_TYPE__CHECK;
> +	msg.success = success;
> +	msg.check = &resp;
> +
> +	if (send_criu_msg(sk, &msg) == -1) {
> +		pr_perror("Can't send response");
> +		success = false;
> +	}
> +
> +	return success ? 0 : 1;
> +}
> +
>  static int cr_service_work(int sk)
>  {
>  	CriuReq *msg = 0;
> @@ -233,6 +347,8 @@ static int cr_service_work(int sk)
>  		return dump_using_req(sk, msg->opts);
>  	case CRIU_REQ_TYPE__RESTORE:
>  		return restore_using_req(sk, msg->opts);
> +	case CRIU_REQ_TYPE__CHECK:
> +		return check_using_req(sk, msg->opts);
>  
>  	default: {
>  		CriuResp resp = CRIU_RESP__INIT;
>