#include "afb-session.h"
#include "verbose.h"
-#define COOKEYCOUNT 8
-#define COOKEYMASK (COOKEYCOUNT - 1)
+#define SIZEUUID 37
+#define HEADCOUNT 16
+#define COOKEYCOUNT 8
+#define COOKEYMASK (COOKEYCOUNT - 1)
-#define NOW (time(NULL))
+#define _MAXEXP_ ((time_t)(~(time_t)0))
+#define _MAXEXP2_ ((time_t)((((unsigned long long)_MAXEXP_) >> 1)))
+#define MAX_EXPIRATION (_MAXEXP_ >= 0 ? _MAXEXP_ : _MAXEXP2_)
+#define NOW (time(NULL))
struct cookie
{
struct afb_session
{
+ struct afb_session *next; /* link to the next */
unsigned refcount;
int timeout;
- time_t expiration; // expiration time of the token
+ time_t expiration; // expiration time of the token
pthread_mutex_t mutex;
- char uuid[37]; // long term authentication of remote client
- char token[37]; // short term authentication of remote client
struct cookie *cookies[COOKEYCOUNT];
+ char idx;
+ char uuid[SIZEUUID]; // long term authentication of remote client
+ char token[SIZEUUID]; // short term authentication of remote client
};
// Session UUID are store in a simple array [for 10 sessions this should be enough]
static struct {
- pthread_mutex_t mutex; // declare a mutex to protect hash table
- struct afb_session **store; // sessions store
- int count; // current number of sessions
+ pthread_mutex_t mutex; // declare a mutex to protect hash table
+ struct afb_session *heads[HEADCOUNT]; // sessions
+ int count; // current number of sessions
int max;
int timeout;
- char initok[37];
+ char initok[SIZEUUID];
} sessions;
/* generate a uuid */
-static void new_uuid(char uuid[37])
+static void new_uuid(char uuid[SIZEUUID])
{
uuid_t newuuid;
uuid_generate(newuuid);
}
// Free context [XXXX Should be protected again memory abort XXXX]
-static void remove_all_cookies(struct afb_session *session)
+static void close_session(struct afb_session *session)
{
int idx;
- struct cookie *cookie, *next;
+ struct cookie *cookie;
- // free cookies
+ /* free cookies */
for (idx = 0 ; idx < COOKEYCOUNT ; idx++) {
- cookie = session->cookies[idx];
- session->cookies[idx] = NULL;
- while (cookie != NULL) {
- next = cookie->next;
+ while ((cookie = session->cookies[idx])) {
+ session->cookies[idx] = cookie->next;
if (cookie->freecb != NULL)
cookie->freecb(cookie->value);
free(cookie);
- cookie = next;
}
}
}
+/* tiny hash function inspired from pearson */
+static int pearson4(const char *text)
+{
+ static uint8_t T[16] = {
+ 4, 1, 6, 0, 9, 14, 11, 5,
+ 2, 3, 12, 15, 10, 7, 8, 13
+ };
+ uint8_t r, c;
+
+ for (r = 0; (c = (uint8_t)*text) ; text++) {
+ r = T[r ^ (15 & c)];
+ r = T[r ^ (c >> 4)];
+ }
+ return r; // % HEADCOUNT;
+}
+
// Create a new store in RAM, not that is too small it will be automatically extended
void afb_session_init (int max_session_count, int timeout, const char *initok)
{
- // let's create as store as hashtable does not have any
- sessions.store = calloc (1 + (unsigned)max_session_count, sizeof *sessions.store);
pthread_mutex_init(&sessions.mutex, NULL);
sessions.max = max_session_count;
sessions.timeout = timeout;
if (initok == NULL)
/* without token, a secret is made to forbid creation of sessions */
new_uuid(sessions.initok);
- else if (strlen(initok) < sizeof(sessions.store[0]->token))
+ else if (strlen(initok) < sizeof sessions.initok)
strcpy(sessions.initok, initok);
else {
- ERROR("initial token '%s' too long (max length 36)", initok);
+ ERROR("initial token '%s' too long (max length %d)", initok, ((int)(sizeof sessions.initok)) - 1);
exit(1);
}
}
return sessions.initok;
}
-static struct afb_session *search (const char* uuid)
+static struct afb_session *search (const char* uuid, int idx)
{
- int idx;
struct afb_session *session;
- assert (uuid != NULL);
-
- pthread_mutex_lock(&sessions.mutex);
-
- for (idx=0; idx < sessions.max; idx++) {
- session = sessions.store[idx];
- if (session && (0 == strcmp (uuid, session->uuid)))
- goto found;
- }
- session = NULL;
+ session = sessions.heads[idx];
+ while (session && strcmp(uuid, session->uuid))
+ session = session->next;
-found:
- pthread_mutex_unlock(&sessions.mutex);
return session;
}
-static int destroy (struct afb_session *session)
+static void destroy (struct afb_session *session)
{
- int idx;
- int status;
+ struct afb_session **prv;
assert (session != NULL);
+ close_session(session);
pthread_mutex_lock(&sessions.mutex);
-
- for (idx=0; idx < sessions.max; idx++) {
- if (sessions.store[idx] == session) {
- sessions.store[idx] = NULL;
+ prv = &sessions.heads[(int)session->idx];
+ while (*prv)
+ if (*prv != session)
+ prv = &((*prv)->next);
+ else {
+ *prv = session->next;
sessions.count--;
- status = 1;
- goto deleted;
+ pthread_mutex_destroy(&session->mutex);
+ free(session);
+ break;
}
- }
- status = 0;
-deleted:
pthread_mutex_unlock(&sessions.mutex);
- return status;
}
-static int add (struct afb_session *session)
+// Loop on every entry and remove old context sessions.hash
+static time_t cleanup ()
{
+ struct afb_session *session, *next;
int idx;
- int status;
-
- assert (session != NULL);
-
- pthread_mutex_lock(&sessions.mutex);
+ time_t now;
- for (idx=0; idx < sessions.max; idx++) {
- if (NULL == sessions.store[idx]) {
- sessions.store[idx] = session;
- sessions.count++;
- status = 1;
- goto added;
+ // Loop on Sessions Table and remove anything that is older than timeout
+ now = NOW;
+ for (idx = 0 ; idx < HEADCOUNT; idx++) {
+ session = sessions.heads[idx];
+ while (session) {
+ next = session->next;
+ if (session->expiration < now)
+ afb_session_close(session);
+ session = next;
}
}
- status = 0;
-added:
- pthread_mutex_unlock(&sessions.mutex);
- return status;
+ return now;
}
-// Check if context timeout or not
-static int is_expired (struct afb_session *ctx, time_t now)
+static void update_timeout(struct afb_session *session, time_t now, int timeout)
{
- assert (ctx != NULL);
- return ctx->expiration < now;
-}
+ time_t expiration;
-// Check if context is active or not
-static int is_active (struct afb_session *ctx, time_t now)
-{
- assert (ctx != NULL);
- return ctx->uuid[0] != 0 && ctx->expiration >= now;
+ /* compute expiration */
+ if (timeout == AFB_SESSION_TIMEOUT_INFINITE)
+ expiration = MAX_EXPIRATION;
+ else {
+ if (timeout == AFB_SESSION_TIMEOUT_DEFAULT)
+ expiration = now + sessions.timeout;
+ else
+ expiration = now + timeout;
+ if (expiration < 0)
+ expiration = MAX_EXPIRATION;
+ }
+
+ /* record the values */
+ session->timeout = timeout;
+ session->expiration = expiration;
}
-// Loop on every entry and remove old context sessions.hash
-static void cleanup (time_t now)
+static void update_expiration(struct afb_session *session, time_t now)
{
- struct afb_session *ctx;
- long idx;
-
- // Loop on Sessions Table and remove anything that is older than timeout
- for (idx=0; idx < sessions.max; idx++) {
- ctx = sessions.store[idx];
- if (ctx != NULL && is_expired(ctx, now)) {
- afb_session_close (ctx);
- }
- }
+ update_timeout(session, now, session->timeout);
}
-static struct afb_session *make_session (const char *uuid, int timeout, time_t now)
+static struct afb_session *add_session (const char *uuid, int timeout, time_t now, int idx)
{
struct afb_session *session;
+ /* check arguments */
if (!AFB_SESSION_TIMEOUT_IS_VALID(timeout)
|| (uuid && strlen(uuid) >= sizeof session->uuid)) {
errno = EINVAL;
- goto error;
+ return NULL;
+ }
+
+ /* check session count */
+ if (sessions.count >= sessions.max) {
+ errno = EBUSY;
+ return NULL;
}
/* allocates a new one */
session = calloc(1, sizeof *session);
if (session == NULL) {
errno = ENOMEM;
- goto error;
+ return NULL;
}
- pthread_mutex_init(&session->mutex, NULL);
- /* generate the uuid */
- if (uuid == NULL) {
- do { new_uuid(session->uuid); } while(search(session->uuid));
- } else {
- strcpy(session->uuid, uuid);
- }
-
- /* init the token */
+ /* initialize */
+ pthread_mutex_init(&session->mutex, NULL);
+ session->refcount = 1;
+ strcpy(session->uuid, uuid);
strcpy(session->token, sessions.initok);
+ update_timeout(session, now, timeout);
- /* init timeout */
- if (timeout == AFB_SESSION_TIMEOUT_DEFAULT)
- timeout = sessions.timeout;
- session->timeout = timeout;
- session->expiration = now + timeout;
- if (timeout == AFB_SESSION_TIMEOUT_INFINITE || session->expiration < 0) {
- session->expiration = (time_t)(~(time_t)0);
- if (session->expiration < 0)
- session->expiration = (time_t)(((unsigned long long)session->expiration) >> 1);
- }
- if (!add (session)) {
- errno = ENOMEM;
- goto error2;
- }
+ /* link */
+ session->idx = (char)idx;
+ session->next = sessions.heads[idx];
+ sessions.heads[idx] = session;
+ sessions.count++;
- session->refcount = 1;
return session;
+}
+
+/* create a new session for the given timeout */
+static struct afb_session *new_session (int timeout, time_t now)
+{
+ int idx;
+ char uuid[SIZEUUID];
-error2:
- free(session);
-error:
- return NULL;
+ do {
+ new_uuid(uuid);
+ idx = pearson4(uuid);
+ } while(search(uuid, idx));
+ return add_session(uuid, timeout, now, idx);
}
/* Creates a new session with 'timeout' */
struct afb_session *afb_session_create (int timeout)
{
time_t now;
+ struct afb_session *session;
/* cleaning */
- now = NOW;
- cleanup (now);
+ pthread_mutex_lock(&sessions.mutex);
+ now = cleanup();
+ session = new_session(timeout, now);
+ pthread_mutex_unlock(&sessions.mutex);
- return make_session(NULL, timeout, now);
+ return session;
}
/* Searchs the session of 'uuid' */
struct afb_session *afb_session_search (const char *uuid)
{
- time_t now;
struct afb_session *session;
/* cleaning */
- now = NOW;
- cleanup (now);
- session = search(uuid);
+ pthread_mutex_lock(&sessions.mutex);
+ cleanup();
+ session = search(uuid, pearson4(uuid));
+ if (session)
+ __atomic_add_fetch(&session->refcount, 1, __ATOMIC_RELAXED);
+ pthread_mutex_unlock(&sessions.mutex);
return session;
}
/* This function will return exiting session or newly created session */
struct afb_session *afb_session_get (const char *uuid, int timeout, int *created)
{
+ int idx;
struct afb_session *session;
time_t now;
/* cleaning */
- now = NOW;
- cleanup (now);
+ pthread_mutex_lock(&sessions.mutex);
+ now = cleanup();
/* search for an existing one not too old */
- if (uuid != NULL) {
- session = search(uuid);
- if (session != NULL) {
+ if (!uuid)
+ session = new_session(timeout, now);
+ else {
+ idx = pearson4(uuid);
+ session = search(uuid, idx);
+ if (session) {
+ __atomic_add_fetch(&session->refcount, 1, __ATOMIC_RELAXED);
+ pthread_mutex_unlock(&sessions.mutex);
if (created)
*created = 0;
- session->refcount++;
return session;
}
+ session = add_session (uuid, timeout, now, idx);
}
+ pthread_mutex_unlock(&sessions.mutex);
- /* no existing session found, create it */
- session = make_session(uuid, timeout, now);
if (created)
*created = !!session;
return session;
}
+/* increase the use count on the session */
struct afb_session *afb_session_addref(struct afb_session *session)
{
if (session != NULL)
return session;
}
+/* decrease the use count of the session */
void afb_session_unref(struct afb_session *session)
{
if (session != NULL) {
assert(session->refcount != 0);
if (!__atomic_sub_fetch(&session->refcount, 1, __ATOMIC_RELAXED)) {
- if (session->uuid[0] == 0) {
+ pthread_mutex_lock(&session->mutex);
+ if (session->uuid[0] == 0)
destroy (session);
- pthread_mutex_destroy(&session->mutex);
- free(session);
- }
+ else
+ pthread_mutex_unlock(&session->mutex);
}
}
}
-// Free Client Session Context
+// close Client Session Context
void afb_session_close (struct afb_session *session)
{
assert(session != NULL);
+ pthread_mutex_lock(&session->mutex);
if (session->uuid[0] != 0) {
session->uuid[0] = 0;
- remove_all_cookies(session);
- if (session->refcount == 0) {
+ if (session->refcount)
+ close_session(session);
+ else {
destroy (session);
- free(session);
+ return;
}
}
+ pthread_mutex_unlock(&session->mutex);
+}
+
+// is the session active?
+int afb_session_is_active (struct afb_session *session)
+{
+ assert(session != NULL);
+ return !!session->uuid[0];
+}
+
+// is the session closed?
+int afb_session_is_closed (struct afb_session *session)
+{
+ assert(session != NULL);
+ return !session->uuid[0];
}
// Sample Generic Ping Debug API
assert(session != NULL);
assert(token != NULL);
- // compare current token with previous one
- if (!is_active (session, NOW))
+ if (!session->uuid[0])
+ return 0;
+
+ if (session->expiration < NOW)
return 0;
if (session->token[0] && strcmp (token, session->token) != 0)
new_uuid(session->token);
// keep track of time for session timeout and further clean up
- if (session->timeout != 0)
- session->expiration = NOW + session->timeout;
+ update_expiration(session, NOW);
}
/* Returns the uuid of 'session' */
*
* The behaviour of this function depends on its parameters:
*
- * @param session the session
- * @param key the key of the cookie
- * @param makecb the creation function
- * @param freecb the release function
- * @param closure an argument
- * @param replace a boolean enforcing replecement of the previous value
+ * @param session the session
+ * @param key the key of the cookie
+ * @param makecb the creation function or NULL
+ * @param freecb the release function or NULL
+ * @param closure an argument for makecb or the value if makecb==NULL
+ * @param replace a boolean enforcing replecement of the previous value
*
* @return the value of the cookie
*
Code Review / src / app-framework-binder.git / blobdiff