/* -*- Mode: C; tab-width: 4 -*- */

/*

+----------------------------------------------------------------------+

| Copyright (c) 1997-2009 The PHP Group |

+----------------------------------------------------------------------+

| This source file is subject to version 3.01 of the PHP license, |

| that is bundled with this package in the file LICENSE, and is |

| available through the world-wide-web at the following url: |

| http://www.php.net/license/3_01.txt |

| If you did not receive a copy of the PHP license and are unable to |

| obtain it through the world-wide-web, please send a note to |

| license@php.net so we can mail you a copy immediately. |

+----------------------------------------------------------------------+

| Original author: Alfonso Jimenez <yo@alfonsojimenez.com> |

| Maintainer: Nicolas Favre-Felix <n.favre-felix@owlient.eu> |

| Maintainer: Nasreddine Bouafif <n.bouafif@owlient.eu> |

| Maintainer: Michael Grunder <michael.grunder@gmail.com> |

+----------------------------------------------------------------------+

*/

#include "common.h"

#include "redis_cmd.h"

#include <ext/hash/php_hash.h>

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#ifdef PHP_SESSION

#include "ext/standard/info.h"

#include "php_redis.h"

#include "redis_session.h"

#include <zend_exceptions.h>

#include "library.h"

#include "cluster_library.h"

#include "php.h"

#include "php_ini.h"

#include "php_variables.h"

#include "SAPI.h"

#include "ext/standard/url.h"

#define REDIS_SESSION_PREFIX "PHPREDIS_SESSION:"

#define CLUSTER_SESSION_PREFIX "PHPREDIS_CLUSTER_SESSION:"

/* Session lock LUA as well as its SHA1 hash */

#define LOCK_DEL_LUA_STR "if redis.call(\"get\",KEYS[1]) == ARGV[1] then return redis.call(\"del\",KEYS[1]) else return 0 end"

#define LOCK_DEL_SHA_STR "b70c2384248f88e6b75b9f89241a180f856ad852"

typedef struct evalCmd {

char *kw;

char *str;

size_t len;

} evalCmd;

static evalCmd lua_cmd[2] = {

{"EVALSHA", ZEND_STRL(LOCK_DEL_SHA_STR)},

{"EVAL", ZEND_STRL(LOCK_DEL_LUA_STR)}

};

typedef enum lockDelCmd {

LOCK_DEL_EVAL,

LOCK_DEL_DELEX,

LOCK_DEL_DELIFEQ,

} lockDelCmd;

typedef enum releaseResult {

DEL_SUCCESS,

DEL_FAILURE,

DEL_NO_CMD,

} delResult;

static inline zend_bool is_redis_ok(const char *str, size_t len) {

return len == 3 && !memcmp(str, "+OK", 3);

}

#define NEGATIVE_LOCK_RESPONSE 1

#define CLUSTER_DEFAULT_PREFIX() \

zend_string_init(CLUSTER_SESSION_PREFIX, sizeof(CLUSTER_SESSION_PREFIX) - 1, 0)

ps_module ps_mod_redis = {

PS_MOD_UPDATE_TIMESTAMP(redis)

};

ps_module ps_mod_redis_cluster = {

PS_MOD_UPDATE_TIMESTAMP(rediscluster)

};

typedef struct {

zend_bool is_locked;

zend_string *session_key;

zend_string *lock_key;

zend_string *lock_secret;

} redis_session_lock_status;

typedef struct redis_pool_member_ {

RedisSock *redis_sock;

int weight;

struct redis_pool_member_ *next;

} redis_pool_member;

typedef struct {

int totalWeight;

int count;

redis_pool_member *head;

redis_session_lock_status lock_status;

zend_bool session_key_missing;

int buster;

} redis_pool;

static void

redis_pool_add(redis_pool *pool, RedisSock *redis_sock, int weight)

{

redis_pool_member *rpm = ecalloc(1, sizeof(*rpm));

rpm->redis_sock = redis_sock;

rpm->weight = weight;

rpm->next = pool->head;

pool->head = rpm;

pool->totalWeight += weight;

}

PHP_REDIS_API void

redis_pool_free(redis_pool *pool) {

redis_pool_member *rpm, *next;

if (pool == NULL)

return;

rpm = pool->head;

while (rpm) {

next = rpm->next;

redis_sock_disconnect(rpm->redis_sock, 0, 1);

redis_free_socket(rpm->redis_sock);

efree(rpm);

rpm = next;

}

/* Cleanup after our lock */

if (pool->lock_status.session_key) zend_string_release(pool->lock_status.session_key);

if (pool->lock_status.lock_secret) zend_string_release(pool->lock_status.lock_secret);

if (pool->lock_status.lock_key) zend_string_release(pool->lock_status.lock_key);

/* Cleanup pool itself */

efree(pool);

}

/* Retrieve session.gc_maxlifetime from php.ini protecting against an integer overflow */

static int session_gc_maxlifetime(void) {

zend_long value = zend_ini_long_literal("session.gc_maxlifetime");

if (value > INT_MAX) {

php_error_docref(NULL, E_NOTICE, "session.gc_maxlifetime overflows INT_MAX, truncating.");

return INT_MAX;

} else if (value <= 0) {

php_error_docref(NULL, E_NOTICE, "session.gc_maxlifetime is <= 0, defaulting to 1440 seconds");

return 1440;

}

return value;

}

/* Retrieve redis.session.compression from php.ini */

static int session_compression_type(void) {

const char *compression = zend_ini_string_literal("redis.session.compression");

if(compression == NULL || *compression == '\0' ||

redis_strncasecmp(compression, ZEND_STRL("none")) == 0)

{

return REDIS_COMPRESSION_NONE;

}

#ifdef HAVE_REDIS_LZF

if(redis_strncasecmp(compression, ZEND_STRL("lzf")) == 0) {

return REDIS_COMPRESSION_LZF;

}

#endif

#ifdef HAVE_REDIS_ZSTD

if(redis_strncasecmp(compression, ZEND_STRL("zstd")) == 0) {

return REDIS_COMPRESSION_ZSTD;

}

#endif

#ifdef HAVE_REDIS_LZ4

if(redis_strncasecmp(compression, ZEND_STRL("lz4")) == 0) {

return REDIS_COMPRESSION_LZ4;

}

#endif

if (strcasecmp(compression, "lzf") ||

strcasecmp(compression, "zstd") ||

strcasecmp(compression, "lz4"))

{

php_error_docref(NULL, E_NOTICE,

"redis.session.compression: '%s' compression is not available. "

"Rebuild phpredis with %s support.", compression, compression);

} else {

php_error_docref(NULL, E_NOTICE,

"redis.session.compression: '%s' is invalid", compression);

}

return REDIS_COMPRESSION_NONE;

}

/* Helper to compress session data */

static int

session_compress_data(RedisSock *redis_sock, char *data, size_t len,

char **compressed_data, size_t *compressed_len)

{

if (redis_sock->compression) {

if(redis_compress(redis_sock, compressed_data, compressed_len, data, len)) {

return 1;

}

}

*compressed_data = data;

*compressed_len = len;

return 0;

}

/* Helper to uncompress session data */

static int

session_uncompress_data(RedisSock *redis_sock, char *data, size_t len,

char **decompressed_data, size_t *decompressed_len) {

if (redis_sock->compression) {

if(redis_uncompress(redis_sock, decompressed_data, decompressed_len, data, len)) {

return 1;

}

}

*decompressed_data = data;

*decompressed_len = len;

return 0;

}

/* Send a command to Redis. Returns byte count written to socket (-1 on failure) */

static int redis_simple_cmd(RedisSock *redis_sock, const char *cmd, int cmdlen,

char **reply, int *replylen)

{

*reply = NULL;

int len_written = redis_sock_write(redis_sock, cmd, cmdlen);

if (len_written >= 0) {

*reply = redis_sock_read(redis_sock, replylen);

}

return len_written;

}

static inline int weighted_seed(zend_string *key) {

/* In GCC the fast-path is one 32-bit load with a union */

union { int pos; } u;

if (EXPECTED(ZSTR_LEN(key) >= sizeof(u.pos))) {

memcpy(&u.pos, ZSTR_VAL(key), sizeof(u.pos));

return u.pos;

}

u.pos = 0;

memcpy(&u.pos, ZSTR_VAL(key), ZSTR_LEN(key));

return u.pos;

}

PHP_REDIS_API redis_pool_member *

redis_pool_get_sock(redis_pool *pool, zend_string *key) {

redis_pool_member *rpm;

int pos, i;

/* In the next release, ensure pool->totalWeight > 0 */

pos = weighted_seed(key) % (pool->totalWeight ? pool->totalWeight : 1);

rpm = pool->head;

for(i = 0; i < pool->totalWeight;) {

if (pos >= i && pos < i + rpm->weight) {

if (redis_sock_server_open(rpm->redis_sock) == 0) {

return rpm;

}

}

i += rpm->weight;

rpm = rpm->next;

}

return NULL;

}

/* Helper to set our session lock key */

static int

set_session_lock_key(RedisSock *redis_sock, const char *cmd, int cmd_len)

{

char *reply;

int sent_len, reply_len;

sent_len = redis_simple_cmd(redis_sock, cmd, cmd_len, &reply, &reply_len);

if (reply) {

if (is_redis_ok(reply, reply_len)) {

efree(reply);

return SUCCESS;

}

efree(reply);

}

/* Return FAILURE in case of network problems */

return sent_len >= 0 ? NEGATIVE_LOCK_RESPONSE : FAILURE;

}

static void generate_lock_key(redis_session_lock_status *status) {

static const char suffix[] = "_LOCK";

if (status->lock_key)

zend_string_release(status->lock_key);

status->lock_key = zend_string_concat2(ZSTR_VAL(status->session_key),

ZSTR_LEN(status->session_key),

ZEND_STRL(suffix));

}

static void generate_lock_secret(redis_session_lock_status *status) {

unsigned char buf[16];

char hostname[HOST_NAME_MAX] = {0};

if (status->lock_secret)

zend_string_release(status->lock_secret);

if (php_random_bytes_silent(buf, sizeof(buf)) == SUCCESS) {

zend_string *s = zend_string_alloc(sizeof(buf) * 2, 0);

zend_bin2hex(ZSTR_VAL(s), buf, sizeof(buf));

ZSTR_VAL(s)[sizeof(buf) * 2] = '\0';

status->lock_secret = s;

return;

}

gethostname(hostname, HOST_NAME_MAX);

status->lock_secret = strpprintf(0, "%s|%ld", hostname, (long)getpid());

}

static int

lock_acquire(RedisSock *redis_sock, redis_session_lock_status *lock_status) {

zend_long wait_time, expiry, retries, attempt = 0;

RedisCmd *cmd;

int result;

/* Short circuit if we are already locked or not using session locks */

if (lock_status->is_locked || !zend_ini_long_literal("redis.session.locking_enabled"))

return SUCCESS;

/* How long to wait between attempts to acquire lock */

wait_time = zend_ini_long_literal("redis.session.lock_wait_time");

if (wait_time == 0) {

wait_time = 20000;

}

/* Maximum number of times to retry (-1 means infinite) */

retries = zend_ini_long_literal("redis.session.lock_retries");

if (retries == 0) {

retries = 100;

}

/* How long should the lock live (in seconds) */

expiry = zend_ini_long_literal("redis.session.lock_expire");

if (expiry == 0) {

expiry = zend_ini_long_literal("max_execution_time");

}

generate_lock_key(lock_status);

generate_lock_secret(lock_status);

if (expiry > 0) {

cmd = redis_cmd_fmt(redis_sock, "SET", "SSssd", lock_status->lock_key,

lock_status->lock_secret, "NX", 2, "PX", 2,

expiry * 1000);

} else {

cmd = redis_cmd_fmt(redis_sock, "SET", "SSs", lock_status->lock_key,

lock_status->lock_secret, "NX", 2);

}

/* Attempt to get our lock */

for (;;) {

result = set_session_lock_key(redis_sock, redis_cmd_str(cmd),

redis_cmd_len(cmd));

if (result == SUCCESS) {

lock_status->is_locked = 1;

break;

} else if (result == FAILURE) {

/* Network failure */

break;

}

/* Lock is busy */

if (retries >= 0 && attempt++ >= retries) {

break;

}

usleep(wait_time);

}

redis_cmd_free(cmd);

/* Success if we're locked */

return lock_status->is_locked ? SUCCESS : FAILURE;

}

static zend_always_inline

zend_bool is_lock_secret(const char *str, size_t len, zend_string *secret) {

return len == ZSTR_LEN(secret) && !redis_strncmp(str, ZSTR_VAL(secret), len);

}

static int

write_allowed(RedisSock *redis_sock, redis_session_lock_status *lock_status) {

RedisCmd *cmd;

if (!zend_ini_long_literal("redis.session.locking_enabled")) {

return 1;

}

/* If locked and redis.session.lock_expire is not set => TTL=max_execution_time

Therefore it is guaranteed that the current process is still holding the lock */

if (lock_status->is_locked && zend_ini_long_literal("redis.session.lock_expire") != 0) {

char *reply = NULL;

int replylen;

/* Command to get our lock key value and compare secrets */

cmd = redis_cmd_fmt(redis_sock, "GET", "S", lock_status->lock_key);

/* Attempt to refresh the lock */

redis_simple_cmd(redis_sock, redis_cmd_str(cmd), redis_cmd_len(cmd),

&reply, &replylen);

redis_cmd_free(cmd);

if (reply == NULL) {

lock_status->is_locked = 0;

} else {

lock_status->is_locked = is_lock_secret(reply, replylen,

lock_status->lock_secret);

efree(reply);

}

/* Issue a warning if we're not locked. We don't attempt to refresh the lock

* if we aren't flagged as locked, so if we're not flagged here something

* failed */

if (!lock_status->is_locked) {

php_error_docref(NULL, E_WARNING, "Session lock expired");

}

}

return lock_status->is_locked;

}

static delResult

get_del_result(RedisSock *redis_sock, const char *reply, int len)

{

zend_bool nocmd = 0;

#define NOCMD_PFX "ERR unknown command"

if (reply == NULL) {

if (redis_sock->err) {

php_error_docref(NULL, E_WARNING, "%s", ZSTR_VAL(redis_sock->err));

nocmd = zend_string_starts_with_cstr(redis_sock->err,

ZEND_STRL(NOCMD_PFX));

redis_sock_clear_err(redis_sock);

}

return nocmd ? DEL_NO_CMD : DEL_FAILURE;

} else if (len == 4 && !redis_strncmp(reply, ZEND_STRL(":1"))) {

return DEL_SUCCESS;

} else {

return DEL_FAILURE;

}

#undef NOCMD_PFX

}

static delResult

lock_release_delex(RedisSock *redis_sock, redis_session_lock_status *status) {

delResult result;

RedisCmd *cmd;

char *reply;

int len;

cmd = redis_cmd_create_literal(redis_sock, "DELEX");

redis_cmd_cat_zstr(cmd, status->lock_key);

redis_cmd_cat_literal(cmd, "IFEQ");

redis_cmd_cat_zstr(cmd, status->lock_secret);

redis_simple_cmd(redis_sock, redis_cmd_str(cmd), redis_cmd_len(cmd), &reply,

&len);

result = get_del_result(redis_sock, reply, len);

if (reply) efree(reply);

redis_cmd_free(cmd);

return result;

}

static delResult

lock_release_delifeq(RedisSock *redis_sock, redis_session_lock_status *status) {

delResult result;

RedisCmd *cmd;

char *reply;

int len;

cmd = redis_cmd_create_literal(redis_sock, "DELIFEQ");

redis_cmd_cat_zstr(cmd, status->lock_key);

redis_cmd_cat_zstr(cmd, status->lock_secret);

redis_simple_cmd(redis_sock, redis_cmd_str(cmd), redis_cmd_len(cmd), &reply,

&len);

result = get_del_result(redis_sock, reply, len);

if (reply) efree(reply);

redis_cmd_free(cmd);

return result;

}

/* Release any session lock we hold and cleanup allocated lock data. This

* function first attempts to use EVALSHA and then falls back to EVAL if

* EVALSHA fails. This will cause Redis to cache the script, so subsequent

* calls should then succeed using EVALSHA. */

static void

lock_release_lua(RedisSock *redis_sock, redis_session_lock_status *status) {

int i, replylen;

RedisCmd *cmd;

char *reply;

/* We first want to try EVALSHA and then fall back to EVAL */

for (i = 0; status->is_locked && i < sizeof(lua_cmd)/sizeof(*lua_cmd); i++)

{

cmd = redis_cmd_fmt(redis_sock, lua_cmd[i].kw, "sdSS", lua_cmd[i].str,

lua_cmd[i].len, 1, status->lock_key,

status->lock_secret);

/* Send it off */

redis_simple_cmd(redis_sock, redis_cmd_str(cmd), redis_cmd_len(cmd),

&reply, &replylen);

/* Release lock and cleanup reply if we got one */

if (reply != NULL) {

status->is_locked = 0;

efree(reply);

}

/* Cleanup command */

redis_cmd_free(cmd);

}

/* Something has failed if we are still locked */

if (status->is_locked) {

php_error_docref(NULL, E_WARNING, "Failed to release session lock");

}

}

static lockDelCmd lock_release_cmd(void) {

const char *cmd;

cmd = zend_ini_string_literal("redis.session.lock_release_cmd");

if (cmd == NULL) {

return LOCK_DEL_EVAL;

} else if (redis_strncasecmp(cmd, ZEND_STRL("DELEX")) == 0) {

return LOCK_DEL_DELEX;

} else if (redis_strncasecmp(cmd, ZEND_STRL("DELIFEQ")) == 0) {

return LOCK_DEL_DELIFEQ;

}

return LOCK_DEL_EVAL;

}

static void

lock_release(RedisSock *redis_sock, redis_session_lock_status *status) {

delResult res = DEL_NO_CMD;

if (status->lock_key == NULL)

return;

switch (lock_release_cmd()) {

case LOCK_DEL_DELEX:

res = lock_release_delex(redis_sock, status);

break;

case LOCK_DEL_DELIFEQ:

res = lock_release_delifeq(redis_sock, status);

break;

case LOCK_DEL_EVAL:

break; /* fallthrough */

}

/* If res == DEL_NO_CMD LUA is selected or the new command didn't exist */

if (res == DEL_NO_CMD)

lock_release_lua(redis_sock, status);

}

/* {{{ PS_OPEN_FUNC */

PS_OPEN_FUNC(redis)

{

php_url *url;

zval params, context, *zv;

int i, j, path_len;

#if PHP_VERSION_ID >= 80600

const char *save_path_str = ZSTR_VAL(save_path);

size_t save_path_len = ZSTR_LEN(save_path);

#else

const char *save_path_str = save_path;

size_t save_path_len = strlen(save_path);

#endif

redis_pool *pool = ecalloc(1, sizeof(*pool));

for (i = 0, j = 0, path_len = save_path_len; i < path_len; i = j + 1) {

/* find beginning of url */

while ( i< path_len && (isspace(save_path_str[i]) || save_path_str[i] == ','))

i++;

/* find end of url */

j = i;

while (j<path_len && !isspace(save_path_str[j]) && save_path_str[j] != ',')

j++;

if (i < j) {

int weight = 1;

double timeout = 86400.0, read_timeout = 0.0;

int persistent = 0, db = -1;

zend_long retry_interval = 0;

zend_string *persistent_id = NULL, *prefix = NULL;

zend_string *user = NULL, *pass = NULL;

/* translate unix: into file: */

if (!redis_strncmp(save_path_str+i, ZEND_STRL("unix:"))) {

int len = j-i;

char *path = estrndup(save_path_str+i, len);

memcpy(path, "file:", sizeof("file:")-1);

url = php_url_parse_ex(path, len);

efree(path);

} else {

url = php_url_parse_ex(save_path_str+i, j-i);

}

if (!url) {

char *path = estrndup(save_path_str+i, j-i);

php_error_docref(NULL, E_WARNING,

"Failed to parse session.save_path (error at offset %d, url was '%s')", i, path);

efree(path);

goto fail;

}

ZVAL_NULL(&context);

/* parse parameters */

if (url->query != NULL) {

HashTable *ht;

char *query;

array_init(&params);

if (url->fragment) {

spprintf(&query, 0, "%s#%s", ZSTR_VAL(url->query), ZSTR_VAL(url->fragment));

} else {

query = estrdup(ZSTR_VAL(url->query));

}

sapi_module.treat_data(PARSE_STRING, query, &params);

ht = Z_ARRVAL(params);

REDIS_CONF_INT_STATIC(ht, "weight", &weight);

REDIS_CONF_BOOL_STATIC(ht, "persistent", &persistent);

REDIS_CONF_INT_STATIC(ht, "database", &db);

REDIS_CONF_DOUBLE_STATIC(ht, "timeout", &timeout);

REDIS_CONF_DOUBLE_STATIC(ht, "read_timeout", &read_timeout);

REDIS_CONF_LONG_STATIC(ht, "retry_interval", &retry_interval);

REDIS_CONF_STRING_STATIC(ht, "persistent_id", &persistent_id);

REDIS_CONF_STRING_STATIC(ht, "prefix", &prefix);

REDIS_CONF_AUTH_STATIC(ht, "auth", &user, &pass);

if ((zv = REDIS_HASH_STR_FIND_TYPE_STATIC(ht, "stream", IS_ARRAY)) != NULL) {

ZVAL_ZVAL(&context, zv, 1, 0);

}

zval_ptr_dtor_nogc(&params);

}

if ((url->path == NULL && url->host == NULL) || weight <= 0 || timeout <= 0) {

char *path = estrndup(save_path_str+i, j-i);

php_error_docref(NULL, E_WARNING,

"Failed to parse session.save_path (error at offset %d, url was '%s')", i, path);

efree(path);

php_url_free(url);

if (persistent_id) zend_string_release(persistent_id);

if (prefix) zend_string_release(prefix);

if (user) zend_string_release(user);

if (pass) zend_string_release(pass);

goto fail;

}

RedisSock *redis_sock;

const char *persistent_id_str;

char *addr, *scheme;

size_t addrlen;

int port, addr_free = 0;

scheme = url->scheme ? ZSTR_VAL(url->scheme) : "tcp";

if (url->host) {

port = url->port;

addrlen = spprintf(&addr, 0, "%s://%s", scheme, ZSTR_VAL(url->host));

addr_free = 1;

} else { /* unix */

port = 0;

addr = ZSTR_VAL(url->path);

addrlen = strlen(addr);

}

persistent_id_str = persistent_id ? ZSTR_VAL(persistent_id) : NULL;

redis_sock = redis_sock_create(REDIS_SOCK_SESSION, addr, addrlen,

port, timeout, read_timeout,

persistent, persistent_id_str,

retry_interval);

if (db >= 0) { /* default is -1 which leaves the choice to redis. */

redis_sock->dbNumber = db;

}

redis_sock->compression = session_compression_type();

redis_sock->compression_level = zend_ini_long_literal("redis.session.compression_level");

redis_sock_set_context_zval(redis_sock, &context);

redis_pool_add(pool, redis_sock, weight);

redis_sock->prefix = prefix;

redis_sock_set_auth(redis_sock, user, pass);

if (addr_free) efree(addr);

if (persistent_id) zend_string_release(persistent_id);

if (user) zend_string_release(user);

if (pass) zend_string_release(pass);

php_url_free(url);

}

}

if (pool->head) {

PS_SET_MOD_DATA(pool);

return SUCCESS;

} else {

php_error_docref(NULL, E_WARNING,

"Unable to extract any servers from session.save_path");

}

fail:

redis_pool_free(pool);

PS_SET_MOD_DATA(NULL);

return FAILURE;

}

/* }}} */

/* {{{ PS_CLOSE_FUNC

*/

PS_CLOSE_FUNC(redis)

{

redis_pool *pool = PS_GET_MOD_DATA();

if (pool) {

if (pool->lock_status.session_key) {

redis_pool_member *rpm = redis_pool_get_sock(pool, pool->lock_status.session_key);

RedisSock *redis_sock = rpm ? rpm->redis_sock : NULL;

if (redis_sock) {

lock_release(redis_sock, &pool->lock_status);

}

}

redis_pool_free(pool);

PS_SET_MOD_DATA(NULL);

}

return SUCCESS;

}

/* }}} */

static zend_string *

redis_session_key(RedisSock *redis_sock, zend_string *key) {

if (redis_sock->prefix == NULL) {

return zend_string_concat2(ZEND_STRL(REDIS_SESSION_PREFIX),

ZSTR_VAL(key), ZSTR_LEN(key));

}

return zend_string_concat2(ZSTR_VAL(redis_sock->prefix),

ZSTR_LEN(redis_sock->prefix),

ZSTR_VAL(key), ZSTR_LEN(key));

}

/* {{{ PS_CREATE_SID_FUNC

*/

PS_CREATE_SID_FUNC(redis)

{

int retries = 3;

redis_pool *pool = PS_GET_MOD_DATA();

if (!pool) {

return php_session_create_id(NULL);

}

while (retries-- > 0) {

zend_string* sid = php_session_create_id((void **) &pool);

redis_pool_member *rpm = redis_pool_get_sock(pool, sid);

RedisSock *redis_sock = rpm ? rpm->redis_sock : NULL;

if (!redis_sock) {

php_error_docref(NULL, E_NOTICE, "Redis connection not available");

zend_string_release(sid);

return php_session_create_id(NULL);

}

if (pool->lock_status.session_key)

zend_string_release(pool->lock_status.session_key);

pool->lock_status.session_key = redis_session_key(redis_sock, sid);

if (lock_acquire(redis_sock, &pool->lock_status) == SUCCESS) {

return sid;

}

zend_string_release(pool->lock_status.session_key);

zend_string_release(sid);

sid = NULL;

}

php_error_docref(NULL, E_WARNING,

"Acquiring session lock failed while creating session_id");

return NULL;

}

/* }}} */

/* {{{ PS_VALIDATE_SID_FUNC

*/

PS_VALIDATE_SID_FUNC(redis)

{

int response_len;

char *response;

RedisCmd *cmd;

if (ZSTR_LEN(key) < 1)

return FAILURE;

redis_pool *pool = PS_GET_MOD_DATA();

redis_pool_member *rpm = redis_pool_get_sock(pool, key);

RedisSock *redis_sock = rpm ? rpm->redis_sock : NULL;

if (!redis_sock) {

php_error_docref(NULL, E_WARNING, "Redis connection not available");

return FAILURE;

}

/* send EXISTS command */

zend_string *session = redis_session_key(redis_sock, key);

cmd = redis_cmd_fmt(redis_sock, "EXISTS", "S", session);

zend_string_release(session);

if (redis_sock_write_cmd(redis_sock, cmd) < 0 ||

(response = redis_sock_read(redis_sock, &response_len)) == NULL)

{

php_error_docref(NULL, E_WARNING, "Error communicating with Redis server");

redis_cmd_free(cmd);

return FAILURE;

}

redis_cmd_free(cmd);

if (response_len == 2 && response[0] == ':' && response[1] == '1') {

efree(response);

return SUCCESS;

} else {

efree(response);

return FAILURE;

}

}

/* }}} */

/* {{{ PS_UPDATE_TIMESTAMP_FUNC

*/

PS_UPDATE_TIMESTAMP_FUNC(redis)

{

RedisCmd *cmd;

int rlen, res;

char *rstr;

if (ZSTR_LEN(key) < 1)

return FAILURE;

redis_pool *pool = PS_GET_MOD_DATA();

/* GETEX already refreshed an existing session during the read */

if (zend_ini_long_literal("redis.session.early_refresh") &&

!pool->session_key_missing

) {

return SUCCESS;

}

redis_pool_member *rpm = redis_pool_get_sock(pool, key);

RedisSock *redis_sock = rpm ? rpm->redis_sock : NULL;

if (!redis_sock) {

php_error_docref(NULL, E_WARNING, "Redis connection not available");

return FAILURE;

}

/* send EXPIRE command */

zend_string *session = redis_session_key(redis_sock, key);

cmd = redis_cmd_fmt(redis_sock, "EXPIRE", "Sd", session, session_gc_maxlifetime());

zend_string_release(session);

if (redis_sock_write(redis_sock, redis_cmd_str(cmd), redis_cmd_len(cmd)) < 0 ||

(rstr = redis_sock_read(redis_sock, &rlen)) == NULL)

{

php_error_docref(NULL, E_WARNING, "Error communicating with Redis server");

redis_cmd_free(cmd);

return FAILURE;

}

redis_cmd_free(cmd);

/* Do the full check in the next major version */

res = rlen == 2 && rstr[0] == ':';

zend_bool missing = res && rstr[1] == '0';

efree(rstr);

if (missing) {

return ps_write_redis(mod_data, key, val, maxlifetime);

}

return res ? SUCCESS : FAILURE;

}

/* }}} */

/* {{{ PS_READ_FUNC

*/

PS_READ_FUNC(redis)

{

char *resp, *compressed_buf;

int resp_len, compressed_free;

size_t compressed_len;

RedisCmd *cmd;

if (!ZSTR_LEN(key))

return FAILURE;

redis_pool *pool = PS_GET_MOD_DATA();

redis_pool_member *rpm = redis_pool_get_sock(pool, key);

RedisSock *redis_sock = rpm ? rpm->redis_sock : NULL;

if (!redis_sock) {

php_error_docref(NULL, E_WARNING, "Redis connection not available");

return FAILURE;

}

if (pool->lock_status.session_key)

zend_string_release(pool->lock_status.session_key);

pool->lock_status.session_key = redis_session_key(redis_sock, key);

/* Update the session ttl if early refresh is enabled */

if (zend_ini_long_literal("redis.session.early_refresh")) {

cmd = redis_cmd_create_literal(redis_sock, "GETEX");

redis_cmd_cat_zstr(cmd, pool->lock_status.session_key);

redis_cmd_cat_literal(cmd, "EX");

redis_cmd_cat_long(cmd, session_gc_maxlifetime());

} else {

cmd = redis_cmd_create_literal(redis_sock, "GET");

redis_cmd_cat_zstr(cmd, pool->lock_status.session_key);

}

if (lock_acquire(redis_sock, &pool->lock_status) != SUCCESS) {

if (zend_ini_long_literal("redis.session.lock_failure_readonly")) {

// opt-in legacy behavior: readonly session

php_error_docref(NULL, E_WARNING, "Failed to acquire session lock, session will be read only");

} else {

php_error_docref(NULL, E_WARNING, "Failed to acquire session lock");

redis_cmd_free(cmd);

return FAILURE;

}

}

if (redis_sock_write_cmd(redis_sock, cmd) < 0) {