1 /*
2 +----------------------------------------------------------------------+
3 | PHP Version 5 |
4 +----------------------------------------------------------------------+
5 | Copyright (c) 1997-2013 The PHP Group |
6 +----------------------------------------------------------------------+
7 | This source file is subject to version 3.01 of the PHP license, |
8 | that is bundled with this package in the file LICENSE, and is |
9 | available through the world-wide-web at the following url: |
10 | http://www.php.net/license/3_01.txt |
11 | If you did not receive a copy of the PHP license and are unable to |
12 | obtain it through the world-wide-web, please send a note to |
13 | license@php.net so we can mail you a copy immediately. |
14 +----------------------------------------------------------------------+
15 | Author: Sascha Schumann <sascha@schumann.cx> |
16 +----------------------------------------------------------------------+
17 */
18
19 /* $Id$ */
20
21 #include "php.h"
22
23 #ifdef HAVE_LIBMM
24
25 #include <unistd.h>
26 #include <mm.h>
27 #include <time.h>
28 #include <sys/stat.h>
29 #include <sys/types.h>
30 #include <fcntl.h>
31
32 #include "php_session.h"
33 #include "mod_mm.h"
34 #include "SAPI.h"
35
36 #ifdef ZTS
37 # error mm is not thread-safe
38 #endif
39
40 #define PS_MM_FILE "session_mm_"
41
42 /* For php_uint32 */
43 #include "ext/standard/basic_functions.h"
44
45 /* This list holds all data associated with one session. */
46
47 typedef struct ps_sd {
48 struct ps_sd *next;
49 php_uint32 hv; /* hash value of key */
50 time_t ctime; /* time of last change */
51 void *data;
52 size_t datalen; /* amount of valid data */
53 size_t alloclen; /* amount of allocated memory for data */
54 char key[1]; /* inline key */
55 } ps_sd;
56
57 typedef struct {
58 MM *mm;
59 ps_sd **hash;
60 php_uint32 hash_max;
61 php_uint32 hash_cnt;
62 pid_t owner;
63 } ps_mm;
64
65 static ps_mm *ps_mm_instance = NULL;
66
67 #if 0
68 # define ps_mm_debug(a) printf a
69 #else
70 # define ps_mm_debug(a)
71 #endif
72
ps_sd_hash(const char * data,int len)73 static inline php_uint32 ps_sd_hash(const char *data, int len)
74 {
75 php_uint32 h;
76 const char *e = data + len;
77
78 for (h = 2166136261U; data < e; ) {
79 h *= 16777619;
80 h ^= *data++;
81 }
82
83 return h;
84 }
85
hash_split(ps_mm * data)86 static void hash_split(ps_mm *data)
87 {
88 php_uint32 nmax;
89 ps_sd **nhash;
90 ps_sd **ohash, **ehash;
91 ps_sd *ps, *next;
92
93 nmax = ((data->hash_max + 1) << 1) - 1;
94 nhash = mm_calloc(data->mm, nmax + 1, sizeof(*data->hash));
95
96 if (!nhash) {
97 /* no further memory to expand hash table */
98 return;
99 }
100
101 ehash = data->hash + data->hash_max + 1;
102 for (ohash = data->hash; ohash < ehash; ohash++) {
103 for (ps = *ohash; ps; ps = next) {
104 next = ps->next;
105 ps->next = nhash[ps->hv & nmax];
106 nhash[ps->hv & nmax] = ps;
107 }
108 }
109 mm_free(data->mm, data->hash);
110
111 data->hash = nhash;
112 data->hash_max = nmax;
113 }
114
ps_sd_new(ps_mm * data,const char * key)115 static ps_sd *ps_sd_new(ps_mm *data, const char *key)
116 {
117 php_uint32 hv, slot;
118 ps_sd *sd;
119 int keylen;
120
121 keylen = strlen(key);
122
123 sd = mm_malloc(data->mm, sizeof(ps_sd) + keylen);
124 if (!sd) {
125 TSRMLS_FETCH();
126
127 php_error_docref(NULL TSRMLS_CC, E_WARNING, "mm_malloc failed, avail %d, err %s", mm_available(data->mm), mm_error());
128 return NULL;
129 }
130
131 hv = ps_sd_hash(key, keylen);
132 slot = hv & data->hash_max;
133
134 sd->ctime = 0;
135 sd->hv = hv;
136 sd->data = NULL;
137 sd->alloclen = sd->datalen = 0;
138
139 memcpy(sd->key, key, keylen + 1);
140
141 sd->next = data->hash[slot];
142 data->hash[slot] = sd;
143
144 data->hash_cnt++;
145
146 if (!sd->next) {
147 if (data->hash_cnt >= data->hash_max) {
148 hash_split(data);
149 }
150 }
151
152 ps_mm_debug(("inserting %s(%p) into slot %d\n", key, sd, slot));
153
154 return sd;
155 }
156
ps_sd_destroy(ps_mm * data,ps_sd * sd)157 static void ps_sd_destroy(ps_mm *data, ps_sd *sd)
158 {
159 php_uint32 slot;
160
161 slot = ps_sd_hash(sd->key, strlen(sd->key)) & data->hash_max;
162
163 if (data->hash[slot] == sd) {
164 data->hash[slot] = sd->next;
165 } else {
166 ps_sd *prev;
167
168 /* There must be some entry before the one we want to delete */
169 for (prev = data->hash[slot]; prev->next != sd; prev = prev->next);
170 prev->next = sd->next;
171 }
172
173 data->hash_cnt--;
174
175 if (sd->data) {
176 mm_free(data->mm, sd->data);
177 }
178
179 mm_free(data->mm, sd);
180 }
181
ps_sd_lookup(ps_mm * data,const char * key,int rw)182 static ps_sd *ps_sd_lookup(ps_mm *data, const char *key, int rw)
183 {
184 php_uint32 hv, slot;
185 ps_sd *ret, *prev;
186
187 hv = ps_sd_hash(key, strlen(key));
188 slot = hv & data->hash_max;
189
190 for (prev = NULL, ret = data->hash[slot]; ret; prev = ret, ret = ret->next) {
191 if (ret->hv == hv && !strcmp(ret->key, key)) {
192 break;
193 }
194 }
195
196 if (ret && rw && ret != data->hash[slot]) {
197 /* Move the entry to the top of the linked list */
198 if (prev) {
199 prev->next = ret->next;
200 }
201
202 ret->next = data->hash[slot];
203 data->hash[slot] = ret;
204 }
205
206 ps_mm_debug(("lookup(%s): ret=%p,hv=%u,slot=%d\n", key, ret, hv, slot));
207
208 return ret;
209 }
210
211 ps_module ps_mod_mm = {
212 PS_MOD(mm)
213 };
214
215 #define PS_MM_DATA ps_mm *data = PS_GET_MOD_DATA()
216
ps_mm_initialize(ps_mm * data,const char * path)217 static int ps_mm_initialize(ps_mm *data, const char *path)
218 {
219 data->owner = getpid();
220 data->mm = mm_create(0, path);
221 if (!data->mm) {
222 return FAILURE;
223 }
224
225 data->hash_cnt = 0;
226 data->hash_max = 511;
227 data->hash = mm_calloc(data->mm, data->hash_max + 1, sizeof(ps_sd *));
228 if (!data->hash) {
229 mm_destroy(data->mm);
230 return FAILURE;
231 }
232
233 return SUCCESS;
234 }
235
ps_mm_destroy(ps_mm * data)236 static void ps_mm_destroy(ps_mm *data)
237 {
238 int h;
239 ps_sd *sd, *next;
240
241 /* This function is called during each module shutdown,
242 but we must not release the shared memory pool, when
243 an Apache child dies! */
244 if (data->owner != getpid()) {
245 return;
246 }
247
248 for (h = 0; h < data->hash_max + 1; h++) {
249 for (sd = data->hash[h]; sd; sd = next) {
250 next = sd->next;
251 ps_sd_destroy(data, sd);
252 }
253 }
254
255 mm_free(data->mm, data->hash);
256 mm_destroy(data->mm);
257 free(data);
258 }
259
PHP_MINIT_FUNCTION(ps_mm)260 PHP_MINIT_FUNCTION(ps_mm)
261 {
262 int save_path_len = strlen(PS(save_path));
263 int mod_name_len = strlen(sapi_module.name);
264 int euid_len;
265 char *ps_mm_path, euid[30];
266 int ret;
267
268 ps_mm_instance = calloc(sizeof(*ps_mm_instance), 1);
269 if (!ps_mm_instance) {
270 return FAILURE;
271 }
272
273 if (!(euid_len = slprintf(euid, sizeof(euid), "%d", geteuid()))) {
274 return FAILURE;
275 }
276
277 /* Directory + '/' + File + Module Name + Effective UID + \0 */
278 ps_mm_path = emalloc(save_path_len + 1 + (sizeof(PS_MM_FILE) - 1) + mod_name_len + euid_len + 1);
279
280 memcpy(ps_mm_path, PS(save_path), save_path_len);
281 if (save_path_len && PS(save_path)[save_path_len - 1] != DEFAULT_SLASH) {
282 ps_mm_path[save_path_len] = DEFAULT_SLASH;
283 save_path_len++;
284 }
285 memcpy(ps_mm_path + save_path_len, PS_MM_FILE, sizeof(PS_MM_FILE) - 1);
286 save_path_len += sizeof(PS_MM_FILE) - 1;
287 memcpy(ps_mm_path + save_path_len, sapi_module.name, mod_name_len);
288 save_path_len += mod_name_len;
289 memcpy(ps_mm_path + save_path_len, euid, euid_len);
290 ps_mm_path[save_path_len + euid_len] = '\0';
291
292 ret = ps_mm_initialize(ps_mm_instance, ps_mm_path);
293
294 efree(ps_mm_path);
295
296 if (ret != SUCCESS) {
297 free(ps_mm_instance);
298 ps_mm_instance = NULL;
299 return FAILURE;
300 }
301
302 php_session_register_module(&ps_mod_mm);
303 return SUCCESS;
304 }
305
PHP_MSHUTDOWN_FUNCTION(ps_mm)306 PHP_MSHUTDOWN_FUNCTION(ps_mm)
307 {
308 if (ps_mm_instance) {
309 ps_mm_destroy(ps_mm_instance);
310 return SUCCESS;
311 }
312 return FAILURE;
313 }
314
PS_OPEN_FUNC(mm)315 PS_OPEN_FUNC(mm)
316 {
317 ps_mm_debug(("open: ps_mm_instance=%p\n", ps_mm_instance));
318
319 if (!ps_mm_instance) {
320 return FAILURE;
321 }
322 PS_SET_MOD_DATA(ps_mm_instance);
323
324 return SUCCESS;
325 }
326
PS_CLOSE_FUNC(mm)327 PS_CLOSE_FUNC(mm)
328 {
329 PS_SET_MOD_DATA(NULL);
330
331 return SUCCESS;
332 }
333
PS_READ_FUNC(mm)334 PS_READ_FUNC(mm)
335 {
336 PS_MM_DATA;
337 ps_sd *sd;
338 int ret = FAILURE;
339
340 mm_lock(data->mm, MM_LOCK_RD);
341
342 sd = ps_sd_lookup(data, key, 0);
343 if (sd) {
344 *vallen = sd->datalen;
345 *val = emalloc(sd->datalen + 1);
346 memcpy(*val, sd->data, sd->datalen);
347 (*val)[sd->datalen] = '\0';
348 ret = SUCCESS;
349 }
350
351 mm_unlock(data->mm);
352
353 return ret;
354 }
355
PS_WRITE_FUNC(mm)356 PS_WRITE_FUNC(mm)
357 {
358 PS_MM_DATA;
359 ps_sd *sd;
360
361 mm_lock(data->mm, MM_LOCK_RW);
362
363 sd = ps_sd_lookup(data, key, 1);
364 if (!sd) {
365 sd = ps_sd_new(data, key);
366 ps_mm_debug(("new entry for %s\n", key));
367 }
368
369 if (sd) {
370 if (vallen >= sd->alloclen) {
371 if (data->mm) {
372 mm_free(data->mm, sd->data);
373 }
374 sd->alloclen = vallen + 1;
375 sd->data = mm_malloc(data->mm, sd->alloclen);
376
377 if (!sd->data) {
378 ps_sd_destroy(data, sd);
379 php_error_docref(NULL TSRMLS_CC, E_WARNING, "cannot allocate new data segment");
380 sd = NULL;
381 }
382 }
383 if (sd) {
384 sd->datalen = vallen;
385 memcpy(sd->data, val, vallen);
386 time(&sd->ctime);
387 }
388 }
389
390 mm_unlock(data->mm);
391
392 return sd ? SUCCESS : FAILURE;
393 }
394
PS_DESTROY_FUNC(mm)395 PS_DESTROY_FUNC(mm)
396 {
397 PS_MM_DATA;
398 ps_sd *sd;
399
400 mm_lock(data->mm, MM_LOCK_RW);
401
402 sd = ps_sd_lookup(data, key, 0);
403 if (sd) {
404 ps_sd_destroy(data, sd);
405 }
406
407 mm_unlock(data->mm);
408
409 return SUCCESS;
410 }
411
PS_GC_FUNC(mm)412 PS_GC_FUNC(mm)
413 {
414 PS_MM_DATA;
415 time_t limit;
416 ps_sd **ohash, **ehash;
417 ps_sd *sd, *next;
418
419 *nrdels = 0;
420 ps_mm_debug(("gc\n"));
421
422 time(&limit);
423
424 limit -= maxlifetime;
425
426 mm_lock(data->mm, MM_LOCK_RW);
427
428 ehash = data->hash + data->hash_max + 1;
429 for (ohash = data->hash; ohash < ehash; ohash++) {
430 for (sd = *ohash; sd; sd = next) {
431 next = sd->next;
432 if (sd->ctime < limit) {
433 ps_mm_debug(("purging %s\n", sd->key));
434 ps_sd_destroy(data, sd);
435 (*nrdels)++;
436 }
437 }
438 }
439
440 mm_unlock(data->mm);
441
442 return SUCCESS;
443 }
444
445 #endif
446
447 /*
448 * Local variables:
449 * tab-width: 4
450 * c-basic-offset: 4
451 * End:
452 * vim600: sw=4 ts=4 fdm=marker
453 * vim<600: sw=4 ts=4
454 */
455
