-
Notifications
You must be signed in to change notification settings - Fork 0
/
scrlock.c
327 lines (280 loc) · 7.56 KB
/
scrlock.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
/* See LICENSE file for license details. */
#include "config.h"
#define _XOPEN_SOURCE 500
#if HAVE_SHADOW_H
#include <shadow.h>
#endif
#include <ctype.h>
#include <errno.h>
#include <pwd.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <xcb/xcb.h>
#include <xcb/xcb_keysyms.h>
#include <xcb/xcb_image.h>
#if HAVE_BSD_AUTH
#include <login_cap.h>
#include <bsd_auth.h>
#endif
struct screen_t {
xcb_connection_t* c;
xcb_screen_t* xcb;
xcb_window_t win;
xcb_gcontext_t fg;
xcb_gcontext_t bg;
xcb_font_t font;
uint32_t text_height;
uint32_t text_width;
struct screen_t* next;
};
static void
die(const char *errstr, ...) {
va_list ap;
va_start(ap, errstr);
vfprintf(stderr, errstr, ap);
va_end(ap);
exit(EXIT_FAILURE);
}
#ifndef HAVE_BSD_AUTH
static const char *
getpw(void) { /* only run as root */
const char *rval;
struct passwd *pw;
pw = getpwuid(getuid());
if(!pw)
die("slock: cannot retrieve password entry (make sure to suid or sgid slock)");
endpwent();
rval = pw->pw_passwd;
#if HAVE_SHADOW_H
if (strlen(rval) >= 1) { /* kludge, assumes pw placeholder entry has len >= 1 */
struct spwd *sp;
sp = getspnam(getenv("USER"));
if(!sp)
die("slock: cannot retrieve shadow entry (make sure to suid or sgid slock)\n");
endspent();
rval = sp->sp_pwdp;
}
#endif
/* drop privileges */
if(setgid(pw->pw_gid) < 0 || setuid(pw->pw_uid) < 0)
die("slock: cannot drop privileges");
return rval;
}
#endif
static void grab_key(struct screen_t* scr)
{
xcb_grab_keyboard_cookie_t cookie;
xcb_grab_keyboard_reply_t* reply;
xcb_generic_error_t* error;
cookie = xcb_grab_keyboard(scr->c, 1, scr->win, XCB_CURRENT_TIME, XCB_GRAB_MODE_ASYNC, XCB_GRAB_MODE_SYNC);
reply = xcb_grab_keyboard_reply(scr->c, cookie, &error);
free(reply);
if(error)
die("Couldn't grab keys : %d\n", error->error_code);
}
static void ungrab_key(struct screen_t* scr)
{
xcb_ungrab_keyboard(scr->c, XCB_CURRENT_TIME);
xcb_ungrab_pointer (scr->c, XCB_CURRENT_TIME);
}
static xcb_font_t load_font(xcb_connection_t* c)
{
static xcb_font_t font = 0;
if(font > 0)
return font;
font = xcb_generate_id(c);
xcb_open_font(c, font, strlen(FONT), FONT);
return font;
}
static void load_gcs(struct screen_t* scr)
{
xcb_connection_t* c = scr->c;
xcb_gcontext_t gc;
uint32_t mask;
uint32_t values[3];
char* word = DISPLAYED_MSG;
xcb_char2b_t xcbword[strlen(DISPLAYED_MSG)];
xcb_query_text_extents_reply_t* reply;
xcb_query_text_extents_cookie_t cookie;
uint32_t i;
/* FG */
gc = xcb_generate_id(c);
mask = XCB_GC_FOREGROUND
| XCB_GC_BACKGROUND
| XCB_GC_FONT;
values[0] = scr->xcb->white_pixel;
values[1] = scr->xcb->black_pixel;
values[2] = load_font(c);
xcb_create_gc(c, gc, scr->xcb->root, mask, values);
scr->fg = gc;
/* BG */
gc = xcb_generate_id(c);
xcb_create_gc(c, gc, scr->xcb->root, mask, values);
scr->bg = gc;
/* Font */
scr->font = values[2];
for(i = 0; i < strlen(word); ++i) {
xcbword[i].byte1 = word[i];
xcbword[i].byte2 = 0;
}
cookie = xcb_query_text_extents(c, scr->font, strlen(word), xcbword);
reply = xcb_query_text_extents_reply(c, cookie, NULL);
scr->text_width = reply->overall_width;
scr->text_height = reply->overall_ascent + reply->overall_descent;
free(reply);
}
static void close_gcs(struct screen_t* scr)
{
/* Nothing to do. */
}
static void open_window(struct screen_t* scr)
{
xcb_window_t win;
xcb_void_cookie_t cookie_win;
xcb_void_cookie_t cookie_map;
xcb_generic_error_t* error;
uint32_t mask;
uint32_t values[3];
/* Create the window. */
win = xcb_generate_id(scr->c);
mask = XCB_CW_BACK_PIXEL
| XCB_CW_OVERRIDE_REDIRECT
| XCB_CW_EVENT_MASK;
values[0] = scr->xcb->black_pixel;
values[1] = 1;
values[2] = XCB_EVENT_MASK_EXPOSURE | XCB_EVENT_MASK_KEY_PRESS;
cookie_win = xcb_create_window_checked(
scr->c,
XCB_COPY_FROM_PARENT,
win,
scr->xcb->root,
0, 0,
scr->xcb->width_in_pixels,
scr->xcb->height_in_pixels,
1,
XCB_WINDOW_CLASS_INPUT_OUTPUT,
scr->xcb->root_visual,
mask, values
);
scr->win = win;
cookie_map = xcb_map_window_checked(scr->c, win);
/* Check errors. */
error = xcb_request_check(scr->c, cookie_win);
if(error)
die("Couldn't create window : %d\n", error->error_code);
error = xcb_request_check(scr->c, cookie_map);
if(error)
die("Couldn't map window : %d\n", error->error_code);
}
static void close_window(struct screen_t* scr)
{
xcb_destroy_window(scr->c, scr->win);
}
static struct screen_t* load_screens(xcb_connection_t* c)
{
struct screen_t* scr;
struct screen_t* act;
struct screen_t* first = NULL;
xcb_screen_iterator_t it;
it = xcb_setup_roots_iterator(xcb_get_setup(c));
for(; it.rem; xcb_screen_next(&it)) {
scr = malloc(sizeof(struct screen_t));
scr->xcb = it.data;
scr->c = c;
load_gcs(scr);
open_window(scr);
if(!first)
first = scr;
else
act->next = scr;
scr->next = NULL;
act = scr;
}
return first;
}
static void free_screens(struct screen_t* scrs)
{
struct screen_t* act = scrs;
struct screen_t* next;
while(act) {
next = act->next;
close_gcs(act);
close_window(act);
free(act);
act = next;
}
}
static void draw_window(struct screen_t* scr, const char* msg, xcb_gcontext_t gc)
{
xcb_rectangle_t bg;
bg.x = bg.y = 0;
bg.width = scr->xcb->width_in_pixels;
bg.height = scr->xcb->height_in_pixels;
xcb_poly_fill_rectangle(scr->c, scr->win, gc, 1, &bg);
if(msg) {
/* TODO draw msg. */
}
}
static void mainloop(struct screen_t* scrs, const char* pws)
{
xcb_connection_t* c = scrs->c;
char passwd[256];
unsigned int len;
int running;
xcb_generic_event_t* ev;
xcb_key_press_event_t* keypress;
uint8_t evtype;
xcb_keysym_t symbol;
xcb_key_symbols_t* syms;
syms = xcb_key_symbols_alloc(c);
len = 0;
running = 1;
while(running && (ev = xcb_wait_for_event(c))) {
evtype = ev->response_type & ~0x80;
/* Drawing the windows. */
if(evtype == XCB_EXPOSE) {
struct screen_t* act = scrs;
while(act) {
draw_window(act, passwd, act->fg);
act = act->next;
}
}
/* Handling the keyboard events. */
else if(evtype == XCB_KEY_PRESS) {
keypress = (xcb_key_press_event_t*)ev;
symbol = xcb_key_press_lookup_keysym(syms, keypress, 0);
/* TODO handle press. */
if(xcb_is_keypad_key(symbol))
running = 0;
}
free(ev);
xcb_flush(c);
}
xcb_key_symbols_free(syms);
}
int main(void)
{
xcb_connection_t* c;
struct screen_t* screens;
const char* pws;
/* Getting password. */
if(!getpwuid(getuid()))
die("scrlock: no password entry for you");
pws = getpw();
/* Opening connection to X server. */
c = xcb_connect(NULL, NULL);
screens = load_screens(c);
grab_key(screens);
xcb_flush(c);
mainloop(screens, pws);
ungrab_key(screens);
free_screens(screens);
xcb_disconnect(c);
return 0;
}