static int prepare_tsock(struct parasite_ctl *ctl, pid_t pid,
struct parasite_init_args *args)
{
int ssock = -1;
socklen_t sk_len;
struct sockaddr_un addr;
pr_info("Putting tsock into pid %d\n", pid);
args->h_addr_len = gen_parasite_saddr(&args->h_addr, getpid());
ssock = ctl->ictx.sock;
sk_len = sizeof(addr);
if (ssock == -1) {
pr_err("No socket in ictx\n");
goto err;
}
if (getsockname(ssock, (struct sockaddr *) &addr, &sk_len) < 0) {
pr_perror("Unable to get name for a socket");
return -1;
}
if (sk_len == sizeof(addr.sun_family)) {
if (bind(ssock, (struct sockaddr *)&args->h_addr, args->h_addr_len) < 0) {
pr_perror("Can't bind socket");
goto err;
}
if (listen(ssock, 1)) {
pr_perror("Can't listen on transport socket");
goto err;
}
}
/* Check a case when parasite can't initialize a command socket */
if (ctl->ictx.flags & INFECT_FAIL_CONNECT)
args->h_addr_len = gen_parasite_saddr(&args->h_addr, getpid() + 1);
/*
* Set to -1 to prevent any accidental misuse. The
* only valid user of it is accept_tsock().
*/
ctl->tsock = -ssock;
return 0;
err:
close_safe(&ssock);
return -1;
}
static int parasite_init(struct parasite_ctl *ctl, pid_t pid, int nr_threads)
{
struct parasite_init_args *args;
static int sock = -1;
args = parasite_args(ctl, struct parasite_init_args);
pr_info("Putting tsock into pid %d\n", pid);
args->h_addr_len = gen_parasite_saddr(&args->h_addr, getpid());
args->p_addr_len = gen_parasite_saddr(&args->p_addr, pid);
args->nr_threads = nr_threads;
if (sock == -1) {
int rst = -1;
if (current_ns_mask & CLONE_NEWNET) {
pr_info("Switching to %d's net for tsock creation\n", pid);
if (switch_ns(pid, &net_ns_desc, &rst))
return -1;
}
sock = socket(PF_UNIX, SOCK_DGRAM, 0);
if (sock < 0)
pr_perror("Can't create socket");
if (rst > 0 && restore_ns(rst, &net_ns_desc) < 0)
return -1;
if (sock < 0)
return -1;
if (bind(sock, (struct sockaddr *)&args->h_addr, args->h_addr_len) < 0) {
pr_perror("Can't bind socket");
goto err;
}
} else {
struct sockaddr addr = { .sa_family = AF_UNSPEC, };
/*
* When the peer of a dgram socket dies the original socket
* remains in connected state, thus denying any connections
* from "other" sources. Unconnect the socket by hands thus
* allowing for parasite to connect back.
*/
if (connect(sock, &addr, sizeof(addr)) < 0) {
pr_perror("Can't unconnect");
goto err;
}
}
if (parasite_execute(PARASITE_CMD_INIT, ctl) < 0) {
pr_err("Can't init parasite\n");
goto err;
}
if (connect(sock, (struct sockaddr *)&args->p_addr, args->p_addr_len) < 0) {
pr_perror("Can't connect a transport socket");
goto err;
}
ctl->tsock = sock;
return 0;
err:
close_safe(&sock);
return -1;
}
