aboutsummaryrefslogtreecommitdiffstats
path: root/mod/photo.php
blob: e8cd95f1cce0ea3d8aa391119416fd9f6773c94b (plain) (blame)
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
<?php

require_once('include/security.php');
require_once('include/photo/photo_driver.php');

function photo_init(&$a) {

	$prvcachecontrol = false;

	switch(argc()) {
		case 4:
			$person = argv(3);
			$res    = argv(2);
			$type   = argv(1);
			break;
		case 2:
			$photo = argv(1);
			break;
		case 1:
		default:
			killme();
			// NOTREACHED
	}

	$observer_xchan = get_observer_hash();

	$default = get_default_profile_photo();

	if(isset($type)) {

		/**
		 * Profile photos - Access controls on default profile photos are not honoured since they need to be exchanged with remote sites.
		 * 
		 */

		if($type === 'profile') {
			switch($res) {

				case 'm':
					$resolution = 5;
					$default = get_default_profile_photo(80);
					break;
				case 's':
					$resolution = 6;
					$default = get_default_profile_photo(48);
					break;
				case 'l':
				default:
					$resolution = 4;
					break;
			}
		}

		$uid = $person;

		$r = q("SELECT * FROM photo WHERE scale = %d AND uid = %d AND photo_usage = %d LIMIT 1",
			intval($resolution),
			intval($uid),
			intval(PHOTO_PROFILE)
		);
		if(count($r)) {
			$data = dbunescbin($r[0]['data']);
			$mimetype = $r[0]['type'];
		}
		if(intval($r[0]['os_storage']))
			$data = file_get_contents($data);
		if(! isset($data)) {
			$data = file_get_contents($default);
			$mimetype = 'image/png';
		}
	}
	else {

		/**
		 * Other photos
		 */

	        /* Check for a cookie to indicate display pixel density, in order to detect high-resolution
		   displays. This procedure was derived from the "Retina Images" by Jeremey Worboys,
		   used in accordance with the Creative Commons Attribution 3.0 Unported License.
		   Project link: https://github.com/Retina-Images/Retina-Images
		   License link: http://creativecommons.org/licenses/by/3.0/
		*/
		$cookie_value = false;
		if (isset($_COOKIE['devicePixelRatio'])) {
		  $cookie_value = intval($_COOKIE['devicePixelRatio']);
		}
		else {
		  // Force revalidation of cache on next request
		  $cache_directive = 'no-cache';
		  $status = 'no cookie';
		}

		$resolution = 0;

		if(strpos($photo,'.') !== false)
			$photo = substr($photo,0,strpos($photo,'.'));
	
		if(substr($photo,-2,1) == '-') {
			$resolution = intval(substr($photo,-1,1));
			$photo = substr($photo,0,-2);
			// If viewing on a high-res screen, attempt to serve a higher resolution image:
			if ($resolution == 2 && ($cookie_value > 1))
			  {
			    $resolution = 1;
			  }
		}
		
		// If using resolution 1, make sure it exists before proceeding:
		if ($resolution == 1)
		  {
		    $r = q("SELECT uid FROM photo WHERE resource_id = '%s' AND scale = %d LIMIT 1",
			   dbesc($photo),
			   intval($resolution)
			   );
		    if (!($r))
		      $resolution = 2;
		  }

		$r = q("SELECT uid FROM photo WHERE resource_id = '%s' AND scale = %d LIMIT 1",
			dbesc($photo),
			intval($resolution)
		);
		if($r) {
			
			$allowed = (($r[0]['uid']) ? perm_is_allowed($r[0]['uid'],$observer_xchan,'view_storage') : true);

			$sql_extra = permissions_sql($r[0]['uid']);

			// Now we'll see if we can access the photo

			$r = q("SELECT * FROM photo WHERE resource_id = '%s' AND scale = %d $sql_extra LIMIT 1",
				dbesc($photo),
				intval($resolution)
			);

			if($r && $allowed) {
				$data = dbunescbin($r[0]['data']);
				$mimetype = $r[0]['type'];
				if(intval($r[0]['os_storage']))
					$data = file_get_contents($data);
			}
			else {

				// Does the picture exist? It may be a remote person with no credentials,
				// but who should otherwise be able to view it. Show a default image to let 
				// them know permissions was denied. It may be possible to view the image 
				// through an authenticated profile visit.
				// There won't be many completely unauthorised people seeing this because
				// they won't have the photo link, so there's a reasonable chance that the person
				// might be able to obtain permission to view it.

				$r = q("SELECT * FROM `photo` WHERE `resource_id` = '%s' AND `scale` = %d LIMIT 1",
					dbesc($photo),
					intval($resolution)
				);
 
				if($r) {
					logger('mod_photo: forbidden. ' . $a->query_string);
					$observer = $a->get_observer();
					logger('mod_photo: observer = ' . (($observer) ? $observer['xchan_addr'] : '(not authenticated)'));
					$data = file_get_contents('images/nosign.png');
					$mimetype = 'image/png';
					$prvcachecontrol = true;
				}
			}
		}
	}

	if(! isset($data)) {
		if(isset($resolution)) {
			switch($resolution) {

				case 4:
					$data = file_get_contents(get_default_profile_photo());
					$mimetype = 'image/png';
					break;
				case 5:
					$data = file_get_contents(get_default_profile_photo(80));
					$mimetype = 'image/png';
					break;
				case 6:
					$data = file_get_contents(get_default_profile_photo(48));
					$mimetype = 'image/png';
					break;
				default:
					killme();
					// NOTREACHED
					break;
			}
		}
	}

	if(isset($res) && intval($res) && $res < 500) {
		$ph = photo_factory($data, $mimetype);
		if($ph->is_valid()) {
			$ph->scaleImageSquare($res);
			$data = $ph->imageString();
			$mimetype = $ph->getType();
		}
	}

	// Writing in cachefile
	if (isset($cachefile) && $cachefile != '')
		file_put_contents($cachefile, $data);

	if(function_exists('header_remove')) {
		header_remove('Pragma');
		header_remove('pragma');
	}

	header("Content-type: " . $mimetype);

	if($prvcachecontrol) {

		// it is a private photo that they have no permission to view.
		// tell the browser not to cache it, in case they authenticate
		// and subsequently have permission to see it

		header("Cache-Control: no-store, no-cache, must-revalidate");

	}
	else {
		// The photo cache default is 1 day to provide a privacy trade-off,
		// as somebody reducing photo permissions on a photo that is already 
		// "in the wild" won't be able to stop the photo from being viewed
		// for this amount amount of time once it is in the browser cache.
		// The privacy expectations of your site members and their perception 
		// of privacy where it affects the entire project may be affected.
		// This has performance considerations but we highly recommend you 
		// leave it alone. 

		$cache = get_config('system','photo_cache_time');
		if(! $cache)
			$cache = (3600 * 24); // 1 day

	 	header("Expires: " . gmdate("D, d M Y H:i:s", time() + $cache) . " GMT");
		header("Cache-Control: max-age=" . $cache);

	}
	echo $data;
	killme();
	// NOTREACHED
}