Merged revisions 312761 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.4

........
  r312761 | mnicholson | 2011-04-05 09:10:34 -0500 (Tue, 05 Apr 2011) | 8 lines

  Limit the number of unauthenticated manager sessions and also limit the time they have to authenticate.

  AST-2011-005

  (closes issue #18996)
  Reported by: tzafrir
  Tested by: mnicholson
........

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.2@312764 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/configs/manager.conf.sample b/configs/manager.conf.sample
index acb7da980b9c2bd974e0a7860d26cc2f74a3b9d2..30dcd649615f908b8c06fe1e0d503061f4a8bcc3 100644 (file)
--- a/configs/manager.conf.sample
+++ b/configs/manager.conf.sample
@@ -25,6 +25,17 @@ enabled = no
 ;webenabled = yes
 port = 5038
 
+; authtimeout specifies the maximum number of seconds a client has to
+; authenticate.  If the client does not authenticate beofre this timeout
+; expires, the client will be disconnected. (default: 30 seconds)
+
+;authtimeout = 30
+
+; authlimit specifies the maximum number of unauthenticated sessions that will
+; be allowed to connect at any given time.
+
+;authlimit = 50
+
 ;httptimeout = 60
 ; a) httptimeout sets the Max-Age of the http cookie
 ; b) httptimeout is the amount of time the webserver waits 

diff --git a/main/manager.c b/main/manager.c
index 2edf2588ba96477591c803d8d06fcde5ecec9d8c..400394c305951a9f773ba4da2731c5a887e1766b 100644 (file)
--- a/main/manager.c
+++ b/main/manager.c
@@ -127,6 +127,8 @@ static const int DEFAULT_DISPLAYCONNECTS    = 1;    /*!< Default setting for displayin
 static const int DEFAULT_TIMESTAMPEVENTS       = 0;    /*!< Default setting for timestampevents */     
 static const int DEFAULT_HTTPTIMEOUT           = 60;   /*!< Default manager http timeout */
 static const int DEFAULT_BROKENEVENTSACTION    = 0;    /*!< Default setting for brokeneventsaction */
+static const int DEFAULT_AUTHTIMEOUT           = 30;   /*!< Default setting for authtimeout */
+static const int DEFAULT_AUTHLIMIT             = 50;   /*!< Default setting for authlimit */
 
 static int displayconnects;
 static int allowmultiplelogin = 1;
@@ -135,9 +137,12 @@ static int httptimeout;
 static int broken_events_action;
 static int manager_enabled = 0;
 static int webmanager_enabled = 0;
+static int authtimeout;
+static int authlimit;
 
 static int block_sockets;
 static int num_sessions;
+static int unauth_sessions = 0;
 
 static int manager_debug;      /*!< enable some debugging code in the manager */
 
@@ -214,6 +219,7 @@ struct mansession_session {
        int send_events;        /*!<  XXX what ? */
        struct eventqent *last_ev;      /*!< last event processed. */
        int writetimeout;       /*!< Timeout for ast_carefulwrite() */
+       time_t authstart;
        int pending_event;         /*!< Pending events indicator in case when waiting_thread is NULL */
        AST_LIST_HEAD_NOLOCK(mansession_datastores, ast_datastore) datastores; /*!< Data stores on the session */
        AST_LIST_ENTRY(mansession_session) list;
@@ -1792,6 +1798,7 @@ static int action_login(struct mansession *s, const struct message *m)
                return -1;
        }
        s->session->authenticated = 1;
+       ast_atomic_fetchadd_int(&unauth_sessions, -1);
        if (manager_displayconnects(s->session))
                ast_verb(2, "%sManager '%s' logged on from %s\n", (s->session->managerid ? "HTTP " : ""), s->session->username, ast_inet_ntoa(s->session->sin.sin_addr));
        ast_log(LOG_EVENT, "%sManager '%s' logged on from %s\n", (s->session->managerid ? "HTTP " : ""), s->session->username, ast_inet_ntoa(s->session->sin.sin_addr));
@@ -3130,6 +3137,8 @@ static int get_input(struct mansession *s, char *output)
        int res, x;
        int maxlen = sizeof(s->session->inbuf) - 1;
        char *src = s->session->inbuf;
+       int timeout = -1;
+       time_t now;
 
        /*
         * Look for \r\n within the buffer. If found, copy to the output
@@ -3157,6 +3166,20 @@ static int get_input(struct mansession *s, char *output)
        }
        res = 0;
        while (res == 0) {
+               /* calculate a timeout if we are not authenticated */
+               if (!s->session->authenticated) {
+                       if(time(&now) == -1) {
+                               ast_log(LOG_ERROR, "error executing time(): %s\n", strerror(errno));
+                               return -1;
+                       }
+
+                       timeout = (authtimeout - (now - s->session->authstart)) * 1000;
+                       if (timeout < 0) {
+                               /* we have timed out */
+                               return 0;
+                       }
+               }
+
                /* XXX do we really need this locking ? */
                ast_mutex_lock(&s->session->__lock);
                if (s->session->pending_event) {
@@ -3167,7 +3190,7 @@ static int get_input(struct mansession *s, char *output)
                s->session->waiting_thread = pthread_self();
                ast_mutex_unlock(&s->session->__lock);
 
-               res = ast_wait_for_input(s->session->fd, -1);   /* return 0 on timeout ? */
+               res = ast_wait_for_input(s->session->fd, timeout);
 
                ast_mutex_lock(&s->session->__lock);
                s->session->waiting_thread = AST_PTHREADT_NULL;
@@ -3200,6 +3223,7 @@ static int do_message(struct mansession *s)
        struct message m = { 0 };
        char header_buf[sizeof(s->session->inbuf)] = { '\0' };
        int res;
+       time_t now;
 
        for (;;) {
                /* Check if any events are pending and do them if needed */
@@ -3207,6 +3231,17 @@ static int do_message(struct mansession *s)
                        return -1;
                res = get_input(s, header_buf);
                if (res == 0) {
+                       if (!s->session->authenticated) {
+                               if(time(&now) == -1) {
+                                       ast_log(LOG_ERROR, "error executing time(): %s\n", strerror(errno));
+                                       return -1;
+                               }
+
+                               if (now - s->session->authstart > authtimeout) {
+                                       ast_log(LOG_EVENT, "Client from %s, failed to authenticate in %d seconds\n", ast_inet_ntoa(s->session->sin.sin_addr), authtimeout);
+                                       return -1;
+                               }
+                       }
                        continue;
                } else if (res > 0) {
                        if (ast_strlen_zero(header_buf))
@@ -3230,14 +3265,23 @@ static int do_message(struct mansession *s)
 static void *session_do(void *data)
 {
        struct ast_tcptls_session_instance *ser = data;
-       struct mansession_session *session = ast_calloc(1, sizeof(*session));
+       struct mansession_session *session = NULL;
        struct mansession s = {.session = NULL, };
        int flags;
        int res;
        struct protoent *p;
 
-       if (session == NULL)
+       if (ast_atomic_fetchadd_int(&unauth_sessions, +1) >= authlimit) {
+               fclose(ser->f);
+               ast_atomic_fetchadd_int(&unauth_sessions, -1);
                goto done;
+       }
+
+       if ((session = ast_calloc(1, sizeof(*session))) == NULL) {
+               fclose(ser->f);
+               ast_atomic_fetchadd_int(&unauth_sessions, -1);
+               goto done;
+       }
 
        /* here we set TCP_NODELAY on the socket to disable Nagle's algorithm.
         * This is necessary to prevent delays (caused by buffering) as we
@@ -3280,6 +3324,13 @@ static void *session_do(void *data)
        ast_atomic_fetchadd_int(&num_sessions, 1);
        AST_LIST_UNLOCK(&sessions);
 
+       if(time(&session->authstart) == -1) {
+               ast_log(LOG_ERROR, "error executing time(): %s; disconnecting client\n", strerror(errno));
+               ast_atomic_fetchadd_int(&unauth_sessions, -1);
+               destroy_session(session);
+               goto done;
+       }
+
        astman_append(&s, "Asterisk Call Manager/%s\r\n", AMI_VERSION); /* welcome prompt */
        for (;;) {
                if ((res = do_message(&s)) < 0 || s.write_error)
@@ -3291,6 +3342,7 @@ static void *session_do(void *data)
                        ast_verb(2, "Manager '%s' logged off from %s\n", session->username, ast_inet_ntoa(session->sin.sin_addr));
                ast_log(LOG_EVENT, "Manager '%s' logged off from %s\n", session->username, ast_inet_ntoa(session->sin.sin_addr));
        } else {
+               ast_atomic_fetchadd_int(&unauth_sessions, -1);
                        if (displayconnects)
                        ast_verb(2, "Connect attempt from '%s' unable to authenticate\n", ast_inet_ntoa(session->sin.sin_addr));
                ast_log(LOG_EVENT, "Failed attempt from %s\n", ast_inet_ntoa(session->sin.sin_addr));
@@ -4186,6 +4238,8 @@ static int __init_manager(int reload)
        block_sockets = DEFAULT_BLOCKSOCKETS;
        timestampevents = DEFAULT_TIMESTAMPEVENTS;
        httptimeout = DEFAULT_HTTPTIMEOUT;
+       authtimeout = DEFAULT_AUTHTIMEOUT;
+       authlimit = DEFAULT_AUTHLIMIT;
 
        if (!cfg || cfg == CONFIG_STATUS_FILEINVALID) {
                ast_log(LOG_NOTICE, "Unable to open AMI configuration manager.conf, or configuration is invalid. Asterisk management interface (AMI) disabled.\n");
@@ -4250,6 +4304,22 @@ static int __init_manager(int reload)
                        manager_debug = ast_true(val);
                } else if (!strcasecmp(var->name, "httptimeout")) {
                        newhttptimeout = atoi(val);
+               } else if (!strcasecmp(var->name, "authtimeout")) {
+                       int timeout = atoi(var->value);
+
+                       if (timeout < 1) {
+                               ast_log(LOG_WARNING, "Invalid authtimeout value '%s', using default value\n", var->value);
+                       } else {
+                               authtimeout = timeout;
+                       }
+               } else if (!strcasecmp(var->name, "authlimit")) {
+                       int limit = atoi(var->value);
+
+                       if (limit < 1) {
+                               ast_log(LOG_WARNING, "Invalid authlimit value '%s', using default value\n", var->value);
+                       } else {
+                               authlimit = limit;
+                       }
                } else {
                        ast_log(LOG_NOTICE, "Invalid keyword <%s> = <%s> in manager.conf [general]\n",
                                var->name, val);