/* $OpenBSD: control.c,v 1.4 2021/08/01 09:07:03 florian Exp $ */

/*

* Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>

*

* Permission to use, copy, modify, and distribute this software for any

* purpose with or without fee is hereby granted, provided that the above

* copyright notice and this permission notice appear in all copies.

*

* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

*/

#include "compat.h"

#include <sys/types.h>

#include <sys/stat.h>

#include <sys/socket.h>

#include <sys/uio.h>

#include <sys/un.h>

#include <errno.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include "control.h"

#include "minibuffer.h"

#include "telescope.h"

#include "utils.h"

#include "ui.h"

#define CONTROL_BACKLOG 5

struct {

struct event ev;

struct event evt;

int fd;

} control_state = {.fd = -1};

struct ctl_conn {

TAILQ_ENTRY(ctl_conn) entry;

struct imsgev iev;

};

struct ctl_conn *control_connbyfd(int);

struct ctl_conn *control_connbypid(pid_t);

void control_close(int);

TAILQ_HEAD(ctl_conns, ctl_conn) ctl_conns = TAILQ_HEAD_INITIALIZER(ctl_conns);

int

control_init(char *path)

{

struct sockaddr_un sun;

int fd;

mode_t old_umask;

if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,

0)) == -1) {

warn("%s: socket", __func__);

return (-1);

}

memset(&sun, 0, sizeof(sun));

sun.sun_family = AF_UNIX;

strlcpy(sun.sun_path, path, sizeof(sun.sun_path));

if (unlink(path) == -1)

if (errno != ENOENT) {

warn("%s: unlink %s", __func__, path);

close(fd);

return (-1);

}

old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);

if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) {

warn("%s: bind: %s", __func__, path);

close(fd);

umask(old_umask);

return (-1);

}

umask(old_umask);

if (chmod(path, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP) == -1) {

warn("%s: chmod", __func__);

close(fd);

(void)unlink(path);

return (-1);

}

return (fd);

}

int

control_listen(int fd)

{

control_state.fd = fd;

if (listen(control_state.fd, CONTROL_BACKLOG) == -1) {

warn("%s: listen", __func__);

return (-1);

}

event_set(&control_state.ev, control_state.fd, EV_READ,

control_accept, NULL);

event_add(&control_state.ev, NULL);

evtimer_set(&control_state.evt, control_accept, NULL);

return (0);

}

void

control_accept(int listenfd, short event, void *bula)

{

int connfd;

socklen_t len;

struct sockaddr_un sun;

struct ctl_conn *c;

event_add(&control_state.ev, NULL);

if ((event & EV_TIMEOUT))

return;

len = sizeof(sun);

if ((connfd = accept4(listenfd, (struct sockaddr *)&sun, &len,

SOCK_CLOEXEC | SOCK_NONBLOCK)) == -1) {

/*

* Pause accept if we are out of file descriptors, or

* libevent will haunt us here too.

*/

if (errno == ENFILE || errno == EMFILE) {

struct timeval evtpause = { 1, 0 };

event_del(&control_state.ev);

evtimer_add(&control_state.evt, &evtpause);

} else if (errno != EWOULDBLOCK && errno != EINTR &&

errno != ECONNABORTED)

message("%s: accept4: %s", __func__, strerror(errno));

return;

}

if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) {

message("%s: calloc: %s", __func__, strerror(errno));

close(connfd);

return;

}

imsg_init(&c->iev.ibuf, connfd);

c->iev.handler = control_dispatch_imsg;

c->iev.events = EV_READ;

event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events,

c->iev.handler, &c->iev);

event_add(&c->iev.ev, NULL);

TAILQ_INSERT_TAIL(&ctl_conns, c, entry);

}

struct ctl_conn *

control_connbyfd(int fd)

{

struct ctl_conn *c;

TAILQ_FOREACH(c, &ctl_conns, entry) {

if (c->iev.ibuf.fd == fd)

break;

}

return (c);

}

struct ctl_conn *

control_connbypid(pid_t pid)

{

struct ctl_conn *c;

TAILQ_FOREACH(c, &ctl_conns, entry) {

if (c->iev.ibuf.pid == pid)

break;

}

return (c);

}

void

control_close(int fd)

{

struct ctl_conn *c;

if ((c = control_connbyfd(fd)) == NULL) {

message("%s: fd %d: not found", __func__, fd);

return;

}

msgbuf_clear(&c->iev.ibuf.w);

TAILQ_REMOVE(&ctl_conns, c, entry);

event_del(&c->iev.ev);

close(c->iev.ibuf.fd);

/* Some file descriptors are available again. */

if (evtimer_pending(&control_state.evt, NULL)) {

evtimer_del(&control_state.evt);

event_add(&control_state.ev, NULL);

}

free(c);

}

void

control_dispatch_imsg(int fd, short event, void *bula)

{

struct ctl_conn *c;

struct imsg imsg;

ssize_t n;

if ((c = control_connbyfd(fd)) == NULL) {

message("%s: fd %d: not found", __func__, fd);

return;

}

if (event & EV_READ) {

if (((n = imsg_read(&c->iev.ibuf)) == -1 && errno != EAGAIN) ||

n == 0) {

control_close(fd);

return;

}

}

if (event & EV_WRITE) {

if (msgbuf_write(&c->iev.ibuf.w) <= 0 && errno != EAGAIN) {

control_close(fd);

return;

}

}

for (;;) {

if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) {

control_close(fd);

return;

}

if (n == 0)

break;

switch (imsg.hdr.type) {

case IMSG_CTL_OPEN_URL: {

static char uri[GEMINI_URL_LEN];

if (IMSG_DATA_SIZE(imsg) >= sizeof(uri))

break;

memset(uri, 0, sizeof(uri));

memcpy(uri, imsg.data, sizeof(uri));

if (uri[IMSG_DATA_SIZE(imsg)-1] != '\0')

break;

ui_remotely_open_link(uri);

break;

}

default:

message("%s: error handling imsg %d", __func__,

imsg.hdr.type);

break;

}

imsg_free(&imsg);

}

imsg_event_add(&c->iev);

}

int

control_imsg_relay(struct imsg *imsg)

{

struct ctl_conn *c;

if ((c = control_connbypid(imsg->hdr.pid)) == NULL)

return (0);

return (imsg_compose_event(&c->iev, imsg->hdr.type, 0, imsg->hdr.pid,

-1, imsg->data, IMSG_DATA_SIZE(*imsg)));

}