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Cleanup and clarify session.c #19631

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243 changes: 145 additions & 98 deletions ext/session/session.c
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Original file line number Diff line number Diff line change
Expand Up @@ -102,6 +102,7 @@ zend_class_entry *php_session_update_timestamp_iface_entry;

static zend_result php_session_send_cookie(void);
static zend_result php_session_abort(void);
static void ppid2sid(zval *proposed_session_id);
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What does PPID stand for?


/* Initialized in MINIT, readonly otherwise. */
static int my_module_number = 0;
Expand Down Expand Up @@ -369,7 +370,7 @@ PHPAPI zend_string *php_session_create_id(PS_CREATE_SID_ARGS)
* ps_modules appropriately */
PHPAPI zend_result php_session_valid_key(const char *key)
{
size_t len;
size_t key_len;
const char *p;
char c;

Expand All @@ -384,11 +385,11 @@ PHPAPI zend_result php_session_valid_key(const char *key)
}
}

len = p - key;
key_len = p - key;

/* Somewhat arbitrary length limit here, but should be way more than
anyone needs and avoids file-level warnings later on if we exceed MAX_PATH */
if (len == 0 || len > PS_MAX_SID_LENGTH) {
if (key_len == 0 || key_len > PS_MAX_SID_LENGTH) {
return FAILURE;
}

Expand All @@ -398,20 +399,21 @@ PHPAPI zend_result php_session_valid_key(const char *key)

static zend_long php_session_gc(bool immediate)
{
zend_long num = -1;
zend_long sessions_deleted = -1;
bool collect = immediate;

/* GC must be done before reading session data. */
if ((PS(mod_data) || PS(mod_user_implemented))) {
/* Use probability-based GC if not forced and probability is configured */
if (!collect && PS(gc_probability) > 0) {
collect = php_random_range(PS(random), 0, PS(gc_divisor) - 1) < PS(gc_probability);
}

if (collect) {
PS(mod)->s_gc(&PS(mod_data), PS(gc_maxlifetime), &num);
PS(mod)->s_gc(&PS(mod_data), PS(gc_maxlifetime), &sessions_deleted);
}
}
return num;
return sessions_deleted;
}

static zend_result php_session_initialize(void)
Expand Down Expand Up @@ -1441,37 +1443,132 @@ static zend_result php_session_send_cookie(void)

PHPAPI const ps_module *_php_find_ps_module(const char *name)
{
const ps_module *ret = NULL;
const ps_module **mod;
int i;
const ps_module *found_module = NULL;
const ps_module **current_module;
int module_index;

for (i = 0, mod = ps_modules; i < MAX_MODULES; i++, mod++) {
if (*mod && !strcasecmp(name, (*mod)->s_name)) {
ret = *mod;
for (module_index = 0, current_module = ps_modules; module_index < MAX_MODULES; module_index++, current_module++) {
if (*current_module && !strcasecmp(name, (*current_module)->s_name)) {
found_module = *current_module;
break;
}
}
return ret;
return found_module;
}

PHPAPI const ps_serializer *_php_find_ps_serializer(const char *name)
{
const ps_serializer *ret = NULL;
const ps_serializer *mod;
const ps_serializer *found_serializer = NULL;
const ps_serializer *current_serializer;

for (mod = ps_serializers; mod->name; mod++) {
if (!strcasecmp(name, mod->name)) {
ret = mod;
for (current_serializer = ps_serializers; current_serializer->name; current_serializer++) {
if (!strcasecmp(name, current_serializer->name)) {
found_serializer = current_serializer;
break;
}
}
return ret;
return found_serializer;
}

static bool should_invalidate_session_for_external_referer(void)
{
zval *referer_data;

/* No external referer check configured */
if (!PS(id) || PS(extern_referer_chk)[0] == '\0') {
return false;
}

/* No SERVER globals available */
if (Z_ISUNDEF(PG(http_globals)[TRACK_VARS_SERVER])) {
return false;
}

/* Get HTTP_REFERER header */
referer_data = zend_hash_str_find(Z_ARRVAL(PG(http_globals)[TRACK_VARS_SERVER]), ZEND_STRL("HTTP_REFERER"));
if (!referer_data || Z_TYPE_P(referer_data) != IS_STRING || Z_STRLEN_P(referer_data) == 0) {
return false;
}

/* Check if referer contains expected string */
return strstr(Z_STRVAL_P(referer_data), PS(extern_referer_chk)) == NULL;
}

static void try_find_session_id_in_global(const char *global_name)
{
zval *global_data, *potential_session_id;

if (PS(id)) {
return;
}

global_data = zend_hash_str_find(&EG(symbol_table), global_name, strlen(global_name));
if (!global_data) {
return;
}

ZVAL_DEREF(global_data);
if (Z_TYPE_P(global_data) != IS_ARRAY) {
return;
}

potential_session_id = zend_hash_find(Z_ARRVAL_P(global_data), PS(session_name));
if (potential_session_id) {
ppid2sid(potential_session_id);
}
}

static bool can_change_session_setting(const char *setting_name, bool check_cookies)
{
if (PS(session_status) == php_session_active) {
char error_msg[256];
snprintf(error_msg, sizeof(error_msg), "Session %s cannot be changed when a session is active", setting_name);
php_session_session_already_started_error(E_WARNING, error_msg);

return false;
}

if (SG(headers_sent) && (!check_cookies || PS(use_cookies))) {
char error_msg[256];
snprintf(error_msg, sizeof(error_msg), "Session %s cannot be changed after headers have already been sent", setting_name);
php_session_headers_already_sent_error(E_WARNING, error_msg);

return false;
}

return true;
}

static void try_find_session_id_in_cookies(void)
{
zval *cookie_data, *potential_session_id;

if (!PS(use_cookies) || PS(id)) {
return;
}

cookie_data = zend_hash_str_find(&EG(symbol_table), ZEND_STRL("_COOKIE"));
if (!cookie_data) {
return;
}

ZVAL_DEREF(cookie_data);
if (Z_TYPE_P(cookie_data) != IS_ARRAY) {
return;
}

potential_session_id = zend_hash_find(Z_ARRVAL_P(cookie_data), PS(session_name));
if (potential_session_id) {
ppid2sid(potential_session_id);
PS(send_cookie) = 0;
PS(define_sid) = 0;
}
}

static void ppid2sid(zval *ppid) {
ZVAL_DEREF(ppid);
if (Z_TYPE_P(ppid) == IS_STRING) {
PS(id) = zend_string_copy(Z_STR_P(ppid));
static void ppid2sid(zval *proposed_session_id) {
ZVAL_DEREF(proposed_session_id);
if (Z_TYPE_P(proposed_session_id) == IS_STRING) {
PS(id) = zend_string_copy(Z_STR_P(proposed_session_id));
PS(send_cookie) = 0;
} else {
PS(id) = NULL;
Expand Down Expand Up @@ -1561,8 +1658,6 @@ PHPAPI zend_result php_session_reset_id(void)

PHPAPI zend_result php_session_start(void)
{
zval *ppid;
zval *data;
char *value;

switch (PS(session_status)) {
Expand Down Expand Up @@ -1607,37 +1702,13 @@ PHPAPI zend_result php_session_start(void)
*/

if (!PS(id)) {
if (PS(use_cookies) && (data = zend_hash_str_find(&EG(symbol_table), ZEND_STRL("_COOKIE")))) {
ZVAL_DEREF(data);
if (Z_TYPE_P(data) == IS_ARRAY && (ppid = zend_hash_find(Z_ARRVAL_P(data), PS(session_name)))) {
ppid2sid(ppid);
PS(send_cookie) = 0;
PS(define_sid) = 0;
}
}
/* Initialize session ID from non cookie values */
try_find_session_id_in_cookies();

if (!PS(use_only_cookies)) {
if (!PS(id) && (data = zend_hash_str_find(&EG(symbol_table), ZEND_STRL("_GET")))) {
ZVAL_DEREF(data);
if (Z_TYPE_P(data) == IS_ARRAY && (ppid = zend_hash_find(Z_ARRVAL_P(data), PS(session_name)))) {
ppid2sid(ppid);
}
}
if (!PS(id) && (data = zend_hash_str_find(&EG(symbol_table), ZEND_STRL("_POST")))) {
ZVAL_DEREF(data);
if (Z_TYPE_P(data) == IS_ARRAY && (ppid = zend_hash_find(Z_ARRVAL_P(data), PS(session_name)))) {
ppid2sid(ppid);
}
}
/* Check whether the current request was referred to by
* an external site which invalidates the previously found id. */
if (PS(id) && PS(extern_referer_chk)[0] != '\0' &&
!Z_ISUNDEF(PG(http_globals)[TRACK_VARS_SERVER]) &&
(data = zend_hash_str_find(Z_ARRVAL(PG(http_globals)[TRACK_VARS_SERVER]), ZEND_STRL("HTTP_REFERER"))) &&
Z_TYPE_P(data) == IS_STRING &&
Z_STRLEN_P(data) != 0 &&
strstr(Z_STRVAL_P(data), PS(extern_referer_chk)) == NULL
) {
try_find_session_id_in_global("_GET");
try_find_session_id_in_global("_POST");
Comment on lines +1708 to +1709
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Passing the length into the function by using ZEND_STRL() like before makes the most sense IMO


if (should_invalidate_session_for_external_referer()) {
zend_string_release_ex(PS(id), 0);
PS(id) = NULL;
}
Expand Down Expand Up @@ -1923,13 +1994,7 @@ PHP_FUNCTION(session_name)
RETURN_THROWS();
}

if (name && PS(session_status) == php_session_active) {
php_session_session_already_started_error(E_WARNING, "Session name cannot be changed when a session is active");
RETURN_FALSE;
}

if (name && SG(headers_sent)) {
php_session_headers_already_sent_error(E_WARNING, "Session name cannot be changed after headers have already been sent");
if (name && !can_change_session_setting("name", false)) {
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Probably should have a php_ prefix

RETURN_FALSE;
}

Expand All @@ -1952,13 +2017,7 @@ PHP_FUNCTION(session_module_name)
RETURN_THROWS();
}

if (name && PS(session_status) == php_session_active) {
php_session_session_already_started_error(E_WARNING, "Session save handler module cannot be changed when a session is active");
RETURN_FALSE;
}

if (name && SG(headers_sent)) {
php_session_headers_already_sent_error(E_WARNING, "Session save handler module cannot be changed after headers have already been sent");
if (name && !can_change_session_setting("save handler module", false)) {
RETURN_FALSE;
}

Expand Down Expand Up @@ -2227,13 +2286,7 @@ PHP_FUNCTION(session_save_path)
RETURN_THROWS();
}

if (name && PS(session_status) == php_session_active) {
php_session_session_already_started_error(E_WARNING, "Session save path cannot be changed when a session is active");
RETURN_FALSE;
}

if (name && SG(headers_sent)) {
php_session_headers_already_sent_error(E_WARNING, "Session save path cannot be changed after headers have already been sent");
if (name && !can_change_session_setting("save path", false)) {
RETURN_FALSE;
}

Expand All @@ -2255,13 +2308,7 @@ PHP_FUNCTION(session_id)
RETURN_THROWS();
}

if (name && PS(session_status) == php_session_active) {
php_session_session_already_started_error(E_WARNING, "Session ID cannot be changed when a session is active");
RETURN_FALSE;
}

if (name && PS(use_cookies) && SG(headers_sent)) {
php_session_headers_already_sent_error(E_WARNING, "Session ID cannot be changed after headers have already been sent");
if (name && !can_change_session_setting("ID", true)) {
RETURN_FALSE;
}

Expand Down Expand Up @@ -2962,24 +3009,24 @@ static PHP_MSHUTDOWN_FUNCTION(session)

static PHP_MINFO_FUNCTION(session)
{
const ps_module **mod;
ps_serializer *ser;
const ps_module **current_save_handler;
ps_serializer *current_serializer;
smart_str save_handlers = {0};
smart_str ser_handlers = {0};
int i;
int handler_index;

/* Get save handlers */
for (i = 0, mod = ps_modules; i < MAX_MODULES; i++, mod++) {
if (*mod && (*mod)->s_name) {
smart_str_appends(&save_handlers, (*mod)->s_name);
/* Collect names of all available save handlers */
for (handler_index = 0, current_save_handler = ps_modules; handler_index < MAX_MODULES; handler_index++, current_save_handler++) {
if (*current_save_handler && (*current_save_handler)->s_name) {
smart_str_appends(&save_handlers, (*current_save_handler)->s_name);
smart_str_appendc(&save_handlers, ' ');
}
}

/* Get serializer handlers */
for (i = 0, ser = ps_serializers; i < MAX_SERIALIZERS; i++, ser++) {
if (ser->name) {
smart_str_appends(&ser_handlers, ser->name);
/* Collect names of all available serializers */
for (handler_index = 0, current_serializer = ps_serializers; handler_index < MAX_SERIALIZERS; handler_index++, current_serializer++) {
if (current_serializer->name) {
smart_str_appends(&ser_handlers, current_serializer->name);
smart_str_appendc(&ser_handlers, ' ');
}
}
Expand Down Expand Up @@ -3019,16 +3066,16 @@ static const zend_module_dep session_deps[] = {

static bool early_find_sid_in(zval *dest, int where, php_session_rfc1867_progress *progress)
{
zval *ppid;
zval *potential_session_id;

if (Z_ISUNDEF(PG(http_globals)[where])) {
return 0;
}

if ((ppid = zend_hash_find(Z_ARRVAL(PG(http_globals)[where]), PS(session_name)))
&& Z_TYPE_P(ppid) == IS_STRING) {
if ((potential_session_id = zend_hash_find(Z_ARRVAL(PG(http_globals)[where]), PS(session_name)))
&& Z_TYPE_P(potential_session_id) == IS_STRING) {
zval_ptr_dtor(dest);
ZVAL_COPY_DEREF(dest, ppid);
ZVAL_COPY_DEREF(dest, potential_session_id);
return 1;
}

Expand Down