#include "afb-session.h"
#include "verbose.h"
+#define HEADCOUNT 16
#define COOKEYCOUNT 8
#define COOKEYMASK (COOKEYCOUNT - 1)
struct afb_session
{
+ struct afb_session *next; /* link to the next */
unsigned refcount;
int timeout;
time_t expiration; // expiration time of the token
pthread_mutex_t mutex;
+ char idx;
char uuid[37]; // long term authentication of remote client
char token[37]; // short term authentication of remote client
struct cookie *cookies[COOKEYCOUNT];
// 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
+ struct afb_session *heads[HEADCOUNT]; // sessions
int count; // current number of sessions
int max;
int timeout;
}
}
+/* 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);
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;
- }
- }
- status = 0;
-deleted:
- pthread_mutex_unlock(&sessions.mutex);
- return status;
-}
-
-static int add (struct afb_session *session)
-{
- int idx;
- int status;
-
- assert (session != NULL);
-
- pthread_mutex_lock(&sessions.mutex);
-
- for (idx=0; idx < sessions.max; idx++) {
- if (NULL == sessions.store[idx]) {
- sessions.store[idx] = session;
- sessions.count++;
- status = 1;
- goto added;
+ pthread_mutex_destroy(&session->mutex);
+ free(session);
+ break;
}
- }
- status = 0;
-added:
pthread_mutex_unlock(&sessions.mutex);
- return status;
}
// Check if context timeout or not
}
// Loop on every entry and remove old context sessions.hash
-static void cleanup (time_t now)
+static time_t cleanup ()
{
- struct afb_session *ctx;
- long idx;
+ struct afb_session *session, *next;
+ int idx;
+ time_t now;
// 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);
+ now = NOW;
+ for (idx = 0 ; idx < HEADCOUNT; idx++) {
+ session = sessions.heads[idx];
+ while (session) {
+ next = session->next;
+ if (is_expired(session, now))
+ afb_session_close(session);
+ session = next;
}
}
+ return now;
}
-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;
if (!AFB_SESSION_TIMEOUT_IS_VALID(timeout)
|| (uuid && strlen(uuid) >= sizeof session->uuid)) {
errno = EINVAL;
- goto error;
+ return NULL;
+ }
+
+ 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;
- }
- 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);
+ return NULL;
}
- /* init the token */
+ pthread_mutex_init(&session->mutex, NULL);
+ session->refcount = 1;
+ strcpy(session->uuid, uuid);
strcpy(session->token, sessions.initok);
/* init timeout */
if (session->expiration < 0)
session->expiration = (time_t)(((unsigned long long)session->expiration) >> 1);
}
- if (!add (session)) {
- errno = ENOMEM;
- goto error2;
- }
- session->refcount = 1;
+ session->idx = (char)idx;
+ session->next = sessions.heads[idx];
+ sessions.heads[idx] = session;
+ sessions.count++;
+
return session;
+}
-error2:
- free(session);
-error:
- return NULL;
+static struct afb_session *new_session (int timeout, time_t now)
+{
+ int idx;
+ char uuid[37];
+
+ 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));
+ 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 (!uuid)
+ session = new_session(timeout, now);
+ else {
+ idx = pearson4(uuid);
+ session = search(uuid, idx);
if (session != NULL) {
+ __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) {
+ if (session->uuid[0] == 0)
destroy (session);
- pthread_mutex_destroy(&session->mutex);
- free(session);
- }
}
}
}
if (session->uuid[0] != 0) {
session->uuid[0] = 0;
remove_all_cookies(session);
- if (session->refcount == 0) {
+ if (session->refcount == 0)
destroy (session);
- free(session);
- }
}
}
Code Review / src / app-framework-binder.git / commitdiff