static void create_context_events(
struct mosquitto_db* db,
struct epoll_event* events,
int* epollfd_index,
int efd,
time_t now,
int i)
{
/* Local bridges never time out in this fashion. */
if (!(db->contexts[i]->keepalive) ||
db->contexts[i]->bridge ||
now - db->contexts[i]->last_msg_in < (time_t)(db->contexts[i]->keepalive) * 3 / 2) {
if (mqtt3_db_message_write(db->contexts[i]) == MOSQ_ERR_SUCCESS) {
nonblocking (db->contexts[i]->sock);
events[*epollfd_index].data.fd = db->contexts[i]->sock;
events[*epollfd_index].events = EPOLLIN | EPOLLRDHUP;
if(db->contexts[i]->out_packet) {
events[*epollfd_index].events |= EPOLLOUT;
}
epoll_ctl (efd, EPOLL_CTL_ADD, db->contexts[i]->sock, &events[*epollfd_index]);
db->contexts[i]->pollfd_index = *epollfd_index;
*epollfd_index = *epollfd_index + 1;
} else {
mqtt3_context_disconnect(db, db->contexts[i]);
}
} else{
if (db->config->connection_messages == true) {
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Client %s has exceeded timeout, disconnecting.", db->contexts[i]->id);
}
/* Client has exceeded keepalive*1.5 */
mqtt3_context_disconnect(db, db->contexts[i]);
}
}
static void loop_handle_reads_writes(struct mosquitto_db *db, struct pollfd *pollfds)
{
int i;
for(i=0; i<db->context_count; i++){
if(db->contexts[i] && db->contexts[i]->sock != INVALID_SOCKET){
assert(pollfds[db->contexts[i]->pollfd_index].fd == db->contexts[i]->sock);
#ifdef WITH_TLS
if(pollfds[db->contexts[i]->pollfd_index].revents & POLLOUT ||
db->contexts[i]->want_write ||
(db->contexts[i]->ssl && db->contexts[i]->state == mosq_cs_new)){
#else
if(pollfds[db->contexts[i]->pollfd_index].revents & POLLOUT){
#endif
if(_mosquitto_packet_write(db->contexts[i])){
if(db->config->connection_messages == true){
if(db->contexts[i]->state != mosq_cs_disconnecting){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Socket write error on client %s, disconnecting.", db->contexts[i]->id);
}else{
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Client %s disconnected.", db->contexts[i]->id);
}
}
/* Write error or other that means we should disconnect */
mqtt3_context_disconnect(db, db->contexts[i]);
}
}
}
if(db->contexts[i] && db->contexts[i]->sock != INVALID_SOCKET){
assert(pollfds[db->contexts[i]->pollfd_index].fd == db->contexts[i]->sock);
#ifdef WITH_TLS
if(pollfds[db->contexts[i]->pollfd_index].revents & POLLIN ||
db->contexts[i]->want_read ||
(db->contexts[i]->ssl && db->contexts[i]->state == mosq_cs_new)){
#else
if(pollfds[db->contexts[i]->pollfd_index].revents & POLLIN){
#endif
if(_mosquitto_packet_read(db, db->contexts[i])){
if(db->config->connection_messages == true){
if(db->contexts[i]->state != mosq_cs_disconnecting){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Socket read error on client %s, disconnecting.", db->contexts[i]->id);
}else{
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Client %s disconnected.", db->contexts[i]->id);
}
}
/* Read error or other that means we should disconnect */
mqtt3_context_disconnect(db, db->contexts[i]);
}
}
}
if(db->contexts[i] && db->contexts[i]->sock != INVALID_SOCKET){
if(pollfds[db->contexts[i]->pollfd_index].revents & (POLLHUP | POLLRDHUP | POLLERR | POLLNVAL)){
do_disconnect(db, i);
}
}
}
}
static void do_disconnect(struct mosquitto_db *db, int context_index)
{
if (db->config->connection_messages == true) {
if(db->contexts[context_index]->state != mosq_cs_disconnecting){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Socket error on client %s, disconnecting.", db->contexts[context_index]->id);
}else{
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Client %s disconnected.", db->contexts[context_index]->id);
}
}
mqtt3_context_disconnect(db, db->contexts[context_index]);
}
int mqtt3_handle_disconnect(struct mosquitto_db *db, struct mosquitto *context)
{//只是将这个sock关闭，设置为INVALID，其连接事件等都没有清楚的，设置了stat为mosq_cs_disconnecting
if(!context){
return MOSQ_ERR_INVAL;
}
if(context->in_packet.remaining_length != 0){
return MOSQ_ERR_PROTOCOL;
}
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "Received DISCONNECT from %s", context->id);
context->state = mosq_cs_disconnecting;//设置主动断开标识，不会发送will-topic
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_SUCCESS;
}
int mqtt3_handle_connect(struct mosquitto_db *db, struct mosquitto *context)
{
char *protocol_name = NULL;
uint8_t protocol_version;
uint8_t connect_flags;
uint8_t connect_ack = 0;
char *client_id = NULL;
char *will_payload = NULL, *will_topic = NULL;
char *will_topic_mount;
uint16_t will_payloadlen;
struct mosquitto_message *will_struct = NULL;
uint8_t will, will_retain, will_qos, clean_session;
uint8_t username_flag, password_flag;
char *username = NULL, *password = NULL;
int rc;
struct _mosquitto_acl_user *acl_tail;
struct mosquitto_client_msg *msg_tail, *msg_prev;
struct mosquitto *found_context;
int slen;
struct _mosquitto_subleaf *leaf;
int i;
#ifdef WITH_TLS
X509 *client_cert = NULL;
X509_NAME *name;
X509_NAME_ENTRY *name_entry;
#endif
#ifdef WITH_SYS_TREE
g_connection_count++;
#endif
g_epoll_mqtt_connections++;
/* Don't accept multiple CONNECT commands. */
if(context->state != mosq_cs_new){
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
if(_mosquitto_read_string(&context->in_packet, &protocol_name)){
rc = 1;
goto handle_connect_error;
return 1;
}
if(!protocol_name){
rc = 3;
goto handle_connect_error;
return 3;
}
if(_mosquitto_read_byte(&context->in_packet, &protocol_version)){
rc = 1;
goto handle_connect_error;
return 1;
}
if(!strcmp(protocol_name, PROTOCOL_NAME_v31)){
if((protocol_version&0x7F) != PROTOCOL_VERSION_v31){
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Invalid protocol version %d in CONNECT from %s.",
protocol_version, context->address);
}
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_PROTOCOL_VERSION);
_mosquitto_free(protocol_name);
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
context->protocol = mosq_p_mqtt31;
}else if(!strcmp(protocol_name, PROTOCOL_NAME_v311)){
if((protocol_version&0x7F) != PROTOCOL_VERSION_v311){
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Invalid protocol version %d in CONNECT from %s.",
protocol_version, context->address);
}
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_PROTOCOL_VERSION);
_mosquitto_free(protocol_name);
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
if((context->in_packet.command&0x0F) != 0x00){
/* Reserved flags not set to 0, must disconnect. */
_mosquitto_free(protocol_name);
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
context->protocol = mosq_p_mqtt311;
}else{
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Invalid protocol \"%s\" in CONNECT from %s.",
protocol_name, context->address);
}
_mosquitto_free(protocol_name);
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
_mosquitto_free(protocol_name);
if(_mosquitto_read_byte(&context->in_packet, &connect_flags)){
rc = 1;
goto handle_connect_error;
}
clean_session = (connect_flags & 0x02) >> 1;
will = connect_flags & 0x04;
will_qos = (connect_flags & 0x18) >> 3;
if(will_qos == 3){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Invalid Will QoS in CONNECT from %s.",
context->address);
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
will_retain = connect_flags & 0x20;
password_flag = connect_flags & 0x40;
username_flag = connect_flags & 0x80;
if(_mosquitto_read_uint16(&context->in_packet, &(context->keepalive))){
rc = 1;
goto handle_connect_error;
}
if(_mosquitto_read_string(&context->in_packet, &client_id)){
rc = 1;
goto handle_connect_error;
}
slen = strlen(client_id);
if(slen == 0){
if(context->protocol == mosq_p_mqtt31){
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_IDENTIFIER_REJECTED);
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}else{ /* mqtt311 */
_mosquitto_free(client_id);
client_id = NULL;
if(clean_session == 0 || db->config->allow_zero_length_clientid == false){
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_IDENTIFIER_REJECTED);
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}else{
client_id = client_id_gen(db);
if(!client_id){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}
}
}
}
/* clientid_prefixes check */
if(db->config->clientid_prefixes){
if(strncmp(db->config->clientid_prefixes, client_id, strlen(db->config->clientid_prefixes))){
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_NOT_AUTHORIZED);
rc = 1;
goto handle_connect_error;
}
}
if(will){
will_struct = _mosquitto_calloc(1, sizeof(struct mosquitto_message));
if(!will_struct){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}
if(_mosquitto_read_string(&context->in_packet, &will_topic)){
rc = 1;
goto handle_connect_error;
}
if(STREMPTY(will_topic)){
rc = 1;
goto handle_connect_error;
}
if(context->listener && context->listener->mount_point){
slen = strlen(context->listener->mount_point) + strlen(will_topic);
will_topic_mount = _mosquitto_malloc(slen+1);
if(!will_topic_mount){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}
snprintf(will_topic_mount, slen, "%s%s", context->listener->mount_point, will_topic);
will_topic_mount[slen] = '\0';
_mosquitto_free(will_topic);
will_topic = will_topic_mount;
}
if(mosquitto_pub_topic_check(will_topic)){
rc = 1;
goto handle_connect_error;
}
if(_mosquitto_read_uint16(&context->in_packet, &will_payloadlen)){
rc = 1;
goto handle_connect_error;
}
if(will_payloadlen > 0){
will_payload = _mosquitto_malloc(will_payloadlen);
if(!will_payload){
rc = 1;
goto handle_connect_error;
}
rc = _mosquitto_read_bytes(&context->in_packet, will_payload, will_payloadlen);
if(rc){
rc = 1;
goto handle_connect_error;
}
}
}else{
if(context->protocol == mosq_p_mqtt311){
if(will_qos != 0 || will_retain != 0){
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
}
}
if(username_flag){
rc = _mosquitto_read_string(&context->in_packet, &username);
if(rc == MOSQ_ERR_SUCCESS){
if(password_flag){
rc = _mosquitto_read_string(&context->in_packet, &password);
if(rc == MOSQ_ERR_NOMEM){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}else if(rc == MOSQ_ERR_PROTOCOL){
if(context->protocol == mosq_p_mqtt31){
/* Password flag given, but no password. Ignore. */
password_flag = 0;
}else if(context->protocol == mosq_p_mqtt311){
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
}
}
}else if(rc == MOSQ_ERR_NOMEM){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}else{
if(context->protocol == mosq_p_mqtt31){
/* Username flag given, but no username. Ignore. */
username_flag = 0;
}else if(context->protocol == mosq_p_mqtt311){
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
}
}else{
if(context->protocol == mosq_p_mqtt311){
if(password_flag){
/* username_flag == 0 && password_flag == 1 is forbidden */
rc = MOSQ_ERR_PROTOCOL;
goto handle_connect_error;
}
}
}
#ifdef WITH_TLS
if(context->listener && context->listener->ssl_ctx && context->listener->use_identity_as_username){
if(!context->ssl){
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
rc = 1;
goto handle_connect_error;
}
#ifdef REAL_WITH_TLS_PSK
if(context->listener->psk_hint){
/* Client should have provided an identity to get this far. */
if(!context->username){
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
rc = 1;
goto handle_connect_error;
}
}else{
#endif /* REAL_WITH_TLS_PSK */
client_cert = SSL_get_peer_certificate(context->ssl);
if(!client_cert){
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
rc = 1;
goto handle_connect_error;
}
name = X509_get_subject_name(client_cert);
if(!name){
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
rc = 1;
goto handle_connect_error;
}
i = X509_NAME_get_index_by_NID(name, NID_commonName, -1);
if(i == -1){
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
rc = 1;
goto handle_connect_error;
}
name_entry = X509_NAME_get_entry(name, i);
context->username = _mosquitto_strdup((char *)ASN1_STRING_data(name_entry->value));
if(!context->username){
rc = 1;
goto handle_connect_error;
}
X509_free(client_cert);
client_cert = NULL;
#ifdef REAL_WITH_TLS_PSK
}
#endif /* REAL_WITH_TLS_PSK */
}else{
#endif /* WITH_TLS */
if(username_flag){
rc = mosquitto_unpwd_check(db, username, password);
switch(rc){
case MOSQ_ERR_SUCCESS:
break;
case MOSQ_ERR_AUTH:
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_NOT_AUTHORIZED);
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
break;
default:
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
break;
}
context->username = username;
context->password = password;
username = NULL; /* Avoid free() in error: below. */
password = NULL;
}
if(!username_flag && db->config->allow_anonymous == false){
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_NOT_AUTHORIZED);
rc = 1;
goto handle_connect_error;
}
#ifdef WITH_TLS
}
#endif
if(context->listener && context->listener->use_username_as_clientid){
if(context->username){
_mosquitto_free(client_id);
client_id = _mosquitto_strdup(context->username);
if(!client_id){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}
}else{
_mosquitto_send_connack(context, 0, CONNACK_REFUSED_NOT_AUTHORIZED);
rc = 1;
goto handle_connect_error;
}
}
/* Find if this client already has an entry. This must be done *after* any security checks. */
HASH_FIND(hh_id, db->contexts_by_id, client_id, strlen(client_id), found_context);
if(found_context){
/* Found a matching client */
if(found_context->sock == INVALID_SOCKET){
/* Client is reconnecting after a disconnect */
/* FIXME - does anything need to be done here? */
}else{
/* Client is already connected, disconnect old version. This is
* done in mqtt3_context_cleanup() below. */
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_ERR, "Client %s already connected, closing old connection.", client_id);
}
}
if(context->protocol == mosq_p_mqtt311){
if(clean_session == 0){
connect_ack |= 0x01;
}
}
context->clean_session = clean_session;
if(context->clean_session == false && found_context->clean_session == false){
if(found_context->msgs){
context->msgs = found_context->msgs;
found_context->msgs = NULL;
mqtt3_db_message_reconnect_reset(db, context);
}
context->subs = found_context->subs;
found_context->subs = NULL;
context->sub_count = found_context->sub_count;
found_context->sub_count = 0;
for(i=0; i<context->sub_count; i++){
if(context->subs[i]){
leaf = context->subs[i]->subs;
while(leaf){
if(leaf->context == found_context){
leaf->context = context;
}
leaf = leaf->next;
}
}
}
}
found_context->clean_session = true;
found_context->state = mosq_cs_disconnecting;
if(g_flag_epoll)
{
epoll_do_disconnect(db,found_context);
}
else
{
do_disconnect(db, found_context);
}
}
/* Associate user with its ACL, assuming we have ACLs loaded. */
if(db->acl_list){
acl_tail = db->acl_list;
while(acl_tail){
if(context->username){
if(acl_tail->username && !strcmp(context->username, acl_tail->username)){
context->acl_list = acl_tail;
break;
}
}else{
if(acl_tail->username == NULL){
context->acl_list = acl_tail;
break;
}
}
acl_tail = acl_tail->next;
}
}else{
context->acl_list = NULL;
}
if(will_struct){
context->will = will_struct;
context->will->topic = will_topic;
if(will_payload){
context->will->payload = will_payload;
context->will->payloadlen = will_payloadlen;
}else{
context->will->payload = NULL;
context->will->payloadlen = 0;
}
context->will->qos = will_qos;
context->will->retain = will_retain;
}
if(db->config->connection_messages == true){
if(context->is_bridge){
if(context->username){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "New bridge connected from %s as %s (c%d, k%d, u'%s').", context->address, client_id, clean_session, context->keepalive, context->username);
}else{
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "New bridge connected from %s as %s (c%d, k%d).", context->address, client_id, clean_session, context->keepalive);
}
}else{
if(context->username){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "New client connected from %s as %s (c%d, k%d, u'%s').", context->address, client_id, clean_session, context->keepalive, context->username);
}else{
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "New client connected from %s as %s (c%d, k%d).", context->address, client_id, clean_session, context->keepalive);
}
}
}
context->id = client_id;
client_id = NULL;
context->clean_session = clean_session;
context->ping_t = 0;
context->is_dropping = false;
if((protocol_version&0x80) == 0x80){
context->is_bridge = true;
}
/* Remove any queued messages that are no longer allowed through ACL,
* assuming a possible change of username. */
msg_tail = context->msgs;
msg_prev = NULL;
while(msg_tail){
if(msg_tail->direction == mosq_md_out){
if(mosquitto_acl_check(db, context, msg_tail->store->topic, MOSQ_ACL_READ) != MOSQ_ERR_SUCCESS){
mosquitto__db_msg_store_deref(db, &msg_tail->store);
if(msg_prev){
msg_prev->next = msg_tail->next;
_mosquitto_free(msg_tail);
msg_tail = msg_prev->next;
}else{
context->msgs = context->msgs->next;
_mosquitto_free(msg_tail);
msg_tail = context->msgs;
}
}else{
msg_prev = msg_tail;
msg_tail = msg_tail->next;
}
}else{
msg_prev = msg_tail;
msg_tail = msg_tail->next;
}
}
HASH_ADD_KEYPTR(hh_id, db->contexts_by_id, context->id, strlen(context->id), context);
#ifdef WITH_PERSISTENCE
if(!clean_session){
db->persistence_changes++;
}
#endif
context->state = mosq_cs_connected;
return _mosquitto_send_connack(context, connect_ack, CONNACK_ACCEPTED);
handle_connect_error:
if(client_id) _mosquitto_free(client_id);
if(username) _mosquitto_free(username);
if(password) _mosquitto_free(password);
if(will_payload) _mosquitto_free(will_payload);
if(will_topic) _mosquitto_free(will_topic);
if(will_struct) _mosquitto_free(will_struct);
#ifdef WITH_TLS
if(client_cert) X509_free(client_cert);
#endif
/* We return an error here which means the client is freed later on. */
return rc;
}
int mqtt3_handle_connect(struct mosquitto_db *db, struct mosquitto *context)
{
char *protocol_name = NULL;
uint8_t protocol_version;
uint8_t connect_flags;
char *client_id = NULL;
char *will_payload = NULL, *will_topic = NULL;
uint16_t will_payloadlen;
struct mosquitto_message *will_struct = NULL;
uint8_t will, will_retain, will_qos, clean_session;
uint8_t username_flag, password_flag;
char *username = NULL, *password = NULL;
int i;
int rc;
struct _mosquitto_acl_user *acl_tail;
int slen;
#ifdef WITH_TLS
X509 *client_cert;
X509_NAME *name;
X509_NAME_ENTRY *name_entry;
#endif
struct _clientid_index_hash *find_cih;
struct _clientid_index_hash *new_cih;
#ifdef WITH_SYS_TREE
g_connection_count++;
#endif
/* Don't accept multiple CONNECT commands. */
if(context->state != mosq_cs_new){
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_PROTOCOL;
}
if(_mosquitto_read_string(&context->in_packet, &protocol_name)){
mqtt3_context_disconnect(db, context);
return 1;
}
if(!protocol_name){
mqtt3_context_disconnect(db, context);
return 3;
}
if(strcmp(protocol_name, PROTOCOL_NAME)){
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Invalid protocol \"%s\" in CONNECT from %s.",
protocol_name, context->address);
}
_mosquitto_free(protocol_name);
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_PROTOCOL;
}
_mosquitto_free(protocol_name);
if(_mosquitto_read_byte(&context->in_packet, &protocol_version)){
mqtt3_context_disconnect(db, context);
return 1;
}
if((protocol_version&0x7F) != PROTOCOL_VERSION){
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Invalid protocol version %d in CONNECT from %s.",
protocol_version, context->address);
}
_mosquitto_send_connack(context, CONNACK_REFUSED_PROTOCOL_VERSION);
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_PROTOCOL;
}
if((protocol_version&0x80) == 0x80){
context->is_bridge = true;
}
if(_mosquitto_read_byte(&context->in_packet, &connect_flags)){
mqtt3_context_disconnect(db, context);
return 1;
}
clean_session = connect_flags & 0x02;
will = connect_flags & 0x04;
will_qos = (connect_flags & 0x18) >> 3;
will_retain = connect_flags & 0x20;
password_flag = connect_flags & 0x40;
username_flag = connect_flags & 0x80;
if(_mosquitto_read_uint16(&context->in_packet, &(context->keepalive))){
mqtt3_context_disconnect(db, context);
return 1;
}
if(_mosquitto_read_string(&context->in_packet, &client_id)){
mqtt3_context_disconnect(db, context);
return 1;
}
slen = strlen(client_id);
#ifdef WITH_STRICT_PROTOCOL
if(slen > 23 || slen == 0){
#else
if(slen == 0){
#endif
_mosquitto_free(client_id);
_mosquitto_send_connack(context, CONNACK_REFUSED_IDENTIFIER_REJECTED);
mqtt3_context_disconnect(db, context);
return 1;
}
/* clientid_prefixes check */
if(db->config->clientid_prefixes){
if(strncmp(db->config->clientid_prefixes, client_id, strlen(db->config->clientid_prefixes))){
_mosquitto_free(client_id);
_mosquitto_send_connack(context, CONNACK_REFUSED_NOT_AUTHORIZED);
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_SUCCESS;
}
}
if(will){
will_struct = _mosquitto_calloc(1, sizeof(struct mosquitto_message));
if(!will_struct){
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}
if(_mosquitto_read_string(&context->in_packet, &will_topic)){
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
if(strlen(will_topic) == 0){
/* FIXME - CONNACK_REFUSED_IDENTIFIER_REJECTED not really appropriate here. */
_mosquitto_send_connack(context, CONNACK_REFUSED_IDENTIFIER_REJECTED);
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
if(_mosquitto_read_uint16(&context->in_packet, &will_payloadlen)){
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
if(will_payloadlen > 0){
will_payload = _mosquitto_malloc(will_payloadlen);
if(!will_payload){
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
rc = _mosquitto_read_bytes(&context->in_packet, will_payload, will_payloadlen);
if(rc){
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
}
}
if(username_flag){
rc = _mosquitto_read_string(&context->in_packet, &username);
if(rc == MOSQ_ERR_SUCCESS){
if(password_flag){
rc = _mosquitto_read_string(&context->in_packet, &password);
if(rc == MOSQ_ERR_NOMEM){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}else if(rc == MOSQ_ERR_PROTOCOL){
/* Password flag given, but no password. Ignore. */
password_flag = 0;
}
}
}else if(rc == MOSQ_ERR_NOMEM){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}else{
/* Username flag given, but no username. Ignore. */
username_flag = 0;
}
}
#ifdef WITH_TLS
if(context->listener->use_identity_as_username){
if(!context->ssl){
_mosquitto_send_connack(context, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
#ifdef REAL_WITH_TLS_PSK
if(context->listener->psk_hint){
/* Client should have provided an identity to get this far. */
if(!context->username){
_mosquitto_send_connack(context, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
}else{
#endif /* REAL_WITH_TLS_PSK */
client_cert = SSL_get_peer_certificate(context->ssl);
if(!client_cert){
_mosquitto_send_connack(context, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
name = X509_get_subject_name(client_cert);
if(!name){
_mosquitto_send_connack(context, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
i = X509_NAME_get_index_by_NID(name, NID_commonName, -1);
if(i == -1){
_mosquitto_send_connack(context, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
name_entry = X509_NAME_get_entry(name, i);
context->username = _mosquitto_strdup((char *)ASN1_STRING_data(name_entry->value));
if(!context->username){
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
#ifdef REAL_WITH_TLS_PSK
}
#endif /* REAL_WITH_TLS_PSK */
}else{
#endif /* WITH_TLS */
if(username_flag){
rc = mosquitto_unpwd_check(db, username, password);
if(rc == MOSQ_ERR_AUTH){
_mosquitto_send_connack(context, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}else if(rc == MOSQ_ERR_INVAL){
goto handle_connect_error;
}
context->username = username;
context->password = password;
username = NULL; /* Avoid free() in error: below. */
password = NULL;
}
if(!username_flag && db->config->allow_anonymous == false){
_mosquitto_send_connack(context, CONNACK_REFUSED_NOT_AUTHORIZED);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
#ifdef WITH_TLS
}
#endif
/* Find if this client already has an entry. This must be done *after* any security checks. */
HASH_FIND_STR(db->clientid_index_hash, client_id, find_cih);
if(find_cih){
i = find_cih->db_context_index;
/* Found a matching client */
if(db->contexts[i]->sock == -1){
/* Client is reconnecting after a disconnect */
/* FIXME - does anything else need to be done here? */
}else{
/* Client is already connected, disconnect old version */
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_ERR, "Client %s already connected, closing old connection.", client_id);
}
}
db->contexts[i]->clean_session = clean_session;
mqtt3_context_cleanup(db, db->contexts[i], false);
db->contexts[i]->state = mosq_cs_connected;
db->contexts[i]->address = _mosquitto_strdup(context->address);
db->contexts[i]->sock = context->sock;
db->contexts[i]->listener = context->listener;
db->contexts[i]->last_msg_in = mosquitto_time();
db->contexts[i]->last_msg_out = mosquitto_time();
db->contexts[i]->keepalive = context->keepalive;
db->contexts[i]->pollfd_index = context->pollfd_index;
#ifdef WITH_TLS
db->contexts[i]->ssl = context->ssl;
#endif
if(context->username){
db->contexts[i]->username = _mosquitto_strdup(context->username);
}
context->sock = -1;
#ifdef WITH_TLS
context->ssl = NULL;
#endif
context->state = mosq_cs_disconnecting;
context = db->contexts[i];
if(context->msgs){
mqtt3_db_message_reconnect_reset(context);
}
}
context->id = client_id;
client_id = NULL;
context->clean_session = clean_session;
context->ping_t = 0;
// Add the client ID to the DB hash table here
new_cih = _mosquitto_malloc(sizeof(struct _clientid_index_hash));
if(!new_cih){
_mosquitto_log_printf(NULL, MOSQ_LOG_ERR, "Error: Out of memory.");
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}
new_cih->id = context->id;
new_cih->db_context_index = context->db_index;
HASH_ADD_KEYPTR(hh, db->clientid_index_hash, context->id, strlen(context->id), new_cih);
#ifdef WITH_PERSISTENCE
if(!clean_session){
db->persistence_changes++;
}
#endif
/* Associate user with its ACL, assuming we have ACLs loaded. */
if(db->acl_list){
acl_tail = db->acl_list;
while(acl_tail){
if(context->username){
if(acl_tail->username && !strcmp(context->username, acl_tail->username)){
context->acl_list = acl_tail;
break;
}
}else{
if(acl_tail->username == NULL){
context->acl_list = acl_tail;
break;
}
}
acl_tail = acl_tail->next;
}
}else{
context->acl_list = NULL;
}
if(will_struct){
if(mosquitto_acl_check(db, context, will_topic, MOSQ_ACL_WRITE) != MOSQ_ERR_SUCCESS){
_mosquitto_send_connack(context, CONNACK_REFUSED_NOT_AUTHORIZED);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
context->will = will_struct;
context->will->topic = will_topic;
if(will_payload){
context->will->payload = will_payload;
context->will->payloadlen = will_payloadlen;
}else{
context->will->payload = NULL;
context->will->payloadlen = 0;
}
context->will->qos = will_qos;
context->will->retain = will_retain;
}
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "New client connected from %s as %s (c%d, k%d).", context->address, context->id, context->clean_session, context->keepalive);
}
context->state = mosq_cs_connected;
return _mosquitto_send_connack(context, CONNACK_ACCEPTED);
handle_connect_error:
if(client_id) _mosquitto_free(client_id);
if(username) _mosquitto_free(username);
if(password) _mosquitto_free(password);
if(will_payload) _mosquitto_free(will_payload);
if(will_topic) _mosquitto_free(will_topic);
if(will_struct) _mosquitto_free(will_struct);
return rc;
}
int mqtt3_handle_disconnect(struct mosquitto_db *db, struct mosquitto *context)
{
if(!context){
return MOSQ_ERR_INVAL;
}
if(context->in_packet.remaining_length != 0){
return MOSQ_ERR_PROTOCOL;
}
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "Received DISCONNECT from %s", context->id);
context->state = mosq_cs_disconnecting;
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_SUCCESS;
}
int mqtt3_handle_subscribe(struct mosquitto_db *db, struct mosquitto *context)
{
int rc = 0;
int rc2;
uint16_t mid;
char *sub;
uint8_t qos;
uint8_t *payload = NULL, *tmp_payload;
uint32_t payloadlen = 0;
int len;
char *sub_mount;
if(!context) return MOSQ_ERR_INVAL;
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "Received SUBSCRIBE from %s", context->id);
/* FIXME - plenty of potential for memory leaks here */
if(_mosquitto_read_uint16(&context->in_packet, &mid)) return 1;
while(context->in_packet.pos < context->in_packet.remaining_length){
sub = NULL;
if(_mosquitto_read_string(&context->in_packet, &sub)){
if(payload) _mosquitto_free(payload);
return 1;
}
if(sub){
if(_mosquitto_read_byte(&context->in_packet, &qos)){
_mosquitto_free(sub);
if(payload) _mosquitto_free(payload);
return 1;
}
if(qos > 2){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Invalid QoS in subscription command from %s, disconnecting.",
context->address);
_mosquitto_free(sub);
if(payload) _mosquitto_free(payload);
return 1;
}
if(_mosquitto_fix_sub_topic(&sub)){
_mosquitto_free(sub);
if(payload) _mosquitto_free(payload);
return 1;
}
if(!strlen(sub)){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Empty subscription string from %s, disconnecting.",
context->address);
_mosquitto_free(sub);
if(payload) _mosquitto_free(payload);
return 1;
}
if(context->listener && context->listener->mount_point){
len = strlen(context->listener->mount_point) + strlen(sub) + 1;
sub_mount = _mosquitto_calloc(len, sizeof(char));
if(!sub_mount){
_mosquitto_free(sub);
if(payload) _mosquitto_free(payload);
return MOSQ_ERR_NOMEM;
}
snprintf(sub_mount, len, "%s%s", context->listener->mount_point, sub);
_mosquitto_free(sub);
sub = sub_mount;
}
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "\t%s (QoS %d)", sub, qos);
rc2 = mqtt3_sub_add(db, context, sub, qos, &db->subs);
if(rc2 == MOSQ_ERR_SUCCESS){
if(mqtt3_retain_queue(db, context, sub, qos)) rc = 1;
}else if(rc2 != -1){
rc = rc2;
}
_mosquitto_log_printf(NULL, MOSQ_LOG_SUBSCRIBE, "%s %d %s", context->id, qos, sub);
_mosquitto_free(sub);
tmp_payload = _mosquitto_realloc(payload, payloadlen + 1);
if(tmp_payload){
payload = tmp_payload;
payload[payloadlen] = qos;
payloadlen++;
}else{
if(payload) _mosquitto_free(payload);
return MOSQ_ERR_NOMEM;
}
}
}
if(_mosquitto_send_suback(context, mid, payloadlen, payload)) rc = 1;
_mosquitto_free(payload);
#ifdef WITH_PERSISTENCE
db->persistence_changes++;
#endif
return rc;
}
static void loop_handle_reads_writes(struct mosquitto_db *db, struct epoll_event *events, int efd)
{
int i, s;
for (i = 0; i < db->context_count; i++) {
if (db->contexts[i] && db->contexts[i]->sock != INVALID_SOCKET){
/* if (events[db->contexts[i]->pollfd_index].data.fd != db->contexts[i]->sock) { */
/* printf ("%d---%d\n", events[db->contexts[i]->pollfd_index].data.fd, db->contexts[i]->sock); */
/* printf ("%d\n", i); */
/* int n; */
/* for (n = 0; n < sizeof (db->contexts); ++n) */
/* { */
/* printf ("%d----%d\n", db->contexts[n]->pollfd_index, events[db->contexts[i]->pollfd_index].data.fd); */
/* } */
/* } */
/* assert(events[db->contexts[i]->pollfd_index].data.fd == db->contexts[i]->sock); */
#ifdef WITH_TLS
if (events[db->contexts[i]->pollfd_index].events & EPOLLOUT ||
db->contexts[i]->want_write ||
(db->contexts[i]->ssl && db->contexts[i]->state == mosq_cs_new)) {
#else
if(events[db->contexts[i]->epollfd_index].events & EPOLLOUT){
#endif
if(_mosquitto_packet_write(db->contexts[i])){
if(db->config->connection_messages == true){
if(db->contexts[i]->state != mosq_cs_disconnecting){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Socket write error on client %s, disconnecting.", db->contexts[i]->id);
}else{
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Client %s disconnected.", db->contexts[i]->id);
}
}
/* Write error or other that means we should disconnect */
mqtt3_context_disconnect(db, db->contexts[i]);
}
}
}
if(db->contexts[i] && db->contexts[i]->sock != INVALID_SOCKET){
/* assert(events[db->contexts[i]->pollfd_index].data.fd == db->contexts[i]->sock); */
#ifdef WITH_TLS
if(events[db->contexts[i]->pollfd_index].events & EPOLLIN ||
db->contexts[i]->want_read ||
(db->contexts[i]->ssl && db->contexts[i]->state == mosq_cs_new)){
#else
if(events[db->contexts[i]->pollfd_index].events & EPOLLIN){
#endif
if(_mosquitto_packet_read(db, db->contexts[i])){
if(db->config->connection_messages == true){
if(db->contexts[i]->state != mosq_cs_disconnecting){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Socket read error on client %s, disconnecting.", db->contexts[i]->id);
}else{
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Client %s disconnected.", db->contexts[i]->id);
}
}
/* Read error or other that means we should disconnect */
mqtt3_context_disconnect(db, db->contexts[i]);
}
}
}
if(db->contexts[i] && db->contexts[i]->sock != INVALID_SOCKET){
if(events[db->contexts[i]->pollfd_index].events & (EPOLLHUP | POLLRDHUP | EPOLLERR)){
s = epoll_ctl (efd, EPOLL_CTL_DEL, events[db->contexts[i]->pollfd_index].data.fd, &events[db->contexts[i]->pollfd_index]);
do_disconnect(db, i);
}
}
}
}
int mosquitto_main_loop(struct mosquitto_db *db, int *listensock, int listensock_count, int listener_max)
{
time_t start_time = time(NULL);
time_t last_backup = time(NULL);
time_t last_store_clean = time(NULL);
time_t now;
int fdcount;
#ifndef WIN32
sigset_t sigblock, origsig;
#endif
int i;
struct pollfd *pollfds = NULL;
int pollfd_count = 0;
int pollfd_index;
#ifndef WIN32
sigemptyset(&sigblock);
sigaddset(&sigblock, SIGINT);
#endif
while(run){
mqtt3_db_sys_update(db, db->config->sys_interval, start_time);
if(listensock_count + db->context_count > pollfd_count){
pollfd_count = listensock_count + db->context_count;
pollfds = _mosquitto_realloc(pollfds, sizeof(struct pollfd)*pollfd_count);
if(!pollfds){
_mosquitto_log_printf(NULL, MOSQ_LOG_ERR, "Error: Out of memory.");
return MOSQ_ERR_NOMEM;
}
}
memset(pollfds, -1, sizeof(struct pollfd)*pollfd_count);
pollfd_index = 0;
for(i=0; i<listensock_count; i++){
pollfds[pollfd_index].fd = listensock[i];
pollfds[pollfd_index].events = POLLIN;
pollfds[pollfd_index].revents = 0;
pollfd_index++;
}
now = time(NULL);
for(i=0; i<db->context_count; i++){
if(db->contexts[i]){
db->contexts[i]->pollfd_index = -1;
if(db->contexts[i]->sock != INVALID_SOCKET){
#ifdef WITH_BRIDGE
if(db->contexts[i]->bridge){
_mosquitto_check_keepalive(db->contexts[i]);
}
#endif
/* Local bridges never time out in this fashion. */
if(!(db->contexts[i]->keepalive) || db->contexts[i]->bridge || now - db->contexts[i]->last_msg_in < (time_t)(db->contexts[i]->keepalive)*3/2){
if(mqtt3_db_message_write(db->contexts[i]) == MOSQ_ERR_SUCCESS){
pollfds[pollfd_index].fd = db->contexts[i]->sock;
pollfds[pollfd_index].events = POLLIN | POLLRDHUP;
pollfds[pollfd_index].revents = 0;
if(db->contexts[i]->out_packet){
pollfds[pollfd_index].events |= POLLOUT;
}
db->contexts[i]->pollfd_index = pollfd_index;
pollfd_index++;
}else{
mqtt3_context_disconnect(db, db->contexts[i]);
}
}else{
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Client %s has exceeded timeout, disconnecting.", db->contexts[i]->id);
}
/* Client has exceeded keepalive*1.5 */
mqtt3_context_disconnect(db, db->contexts[i]);
}
}else{
#ifdef WITH_BRIDGE
if(db->contexts[i]->bridge){
/* Want to try to restart the bridge connection */
if(!db->contexts[i]->bridge->restart_t){
db->contexts[i]->bridge->restart_t = time(NULL)+db->contexts[i]->bridge->restart_timeout;
}else{
if(db->contexts[i]->bridge->start_type == bst_automatic && time(NULL) > db->contexts[i]->bridge->restart_t){
db->contexts[i]->bridge->restart_t = 0;
if(mqtt3_bridge_connect(db, db->contexts[i]) == MOSQ_ERR_SUCCESS){
pollfds[pollfd_index].fd = db->contexts[i]->sock;
pollfds[pollfd_index].events = POLLIN | POLLRDHUP;
pollfds[pollfd_index].revents = 0;
if(db->contexts[i]->out_packet){
pollfds[pollfd_index].events |= POLLOUT;
}
db->contexts[i]->pollfd_index = pollfd_index;
pollfd_index++;
}else{
/* Retry later. */
db->contexts[i]->bridge->restart_t = time(NULL)+db->contexts[i]->bridge->restart_timeout;
}
}
}
}else{
#endif
if(db->contexts[i]->clean_session == true){
mqtt3_context_cleanup(db, db->contexts[i], true);
db->contexts[i] = NULL;
}else if(db->config->persistent_client_expiration > 0){
/* This is a persistent client, check to see if the
* last time it connected was longer than
* persistent_client_expiration seconds ago. If so,
* expire it and clean up.
*/
if(time(NULL) > db->contexts[i]->disconnect_t+db->config->persistent_client_expiration){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "Expiring persistent client %s due to timeout.", db->contexts[i]->id);
g_clients_expired++;
db->contexts[i]->clean_session = true;
mqtt3_context_cleanup(db, db->contexts[i], true);
db->contexts[i] = NULL;
}
}
#ifdef WITH_BRIDGE
}
#endif
}
}
}
mqtt3_db_message_timeout_check(db, db->config->retry_interval);
#ifndef WIN32
sigprocmask(SIG_SETMASK, &sigblock, &origsig);
fdcount = poll(pollfds, pollfd_index, 100);
sigprocmask(SIG_SETMASK, &origsig, NULL);
#else
fdcount = WSAPoll(pollfds, pollfd_index, 100);
#endif
if(fdcount == -1){
loop_handle_errors(db, pollfds);
}else{
loop_handle_reads_writes(db, pollfds);
for(i=0; i<listensock_count; i++){
if(pollfds[i].revents & (POLLIN | POLLPRI)){
while(mqtt3_socket_accept(db, listensock[i]) != -1){
}
}
}
}
#ifdef WITH_PERSISTENCE
if(db->config->persistence && db->config->autosave_interval){
if(db->config->autosave_on_changes){
if(db->persistence_changes > db->config->autosave_interval){
mqtt3_db_backup(db, false, false);
db->persistence_changes = 0;
}
}else{
if(last_backup + db->config->autosave_interval < now){
mqtt3_db_backup(db, false, false);
last_backup = time(NULL);
}
}
}
#endif
if(!db->config->store_clean_interval || last_store_clean + db->config->store_clean_interval < now){
mqtt3_db_store_clean(db);
last_store_clean = time(NULL);
}
#ifdef WITH_PERSISTENCE
if(flag_db_backup){
mqtt3_db_backup(db, false, false);
flag_db_backup = false;
}
#endif
if(flag_reload){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Reloading config.");
mqtt3_config_read(db->config, true);
mosquitto_security_cleanup(db, true);
mosquitto_security_init(db, true);
mosquitto_security_apply(db);
mqtt3_log_init(db->config->log_type, db->config->log_dest);
flag_reload = false;
}
if(flag_tree_print){
mqtt3_sub_tree_print(&db->subs, 0);
flag_tree_print = false;
}
}
if(pollfds) _mosquitto_free(pollfds);
return MOSQ_ERR_SUCCESS;
}
int mqtt3_handle_connect(struct mosquitto_db *db, struct mosquitto *context)
{
char *protocol_name = NULL;
uint8_t protocol_version;
uint8_t connect_flags;
char *client_id = NULL;
char *will_payload = NULL, *will_topic = NULL;
uint16_t will_payloadlen;
struct mosquitto_message *will_struct = NULL;
uint8_t will, will_retain, will_qos, clean_session;
uint8_t username_flag, password_flag;
char *username = NULL, *password = NULL;
int rc;
int slen;
#ifdef WITH_SYS_TREE
g_connection_count++;
#endif
/* Don't accept multiple CONNECT commands. */
if(context->state != mosq_cs_new){//已经connect过了
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_PROTOCOL;
}
//读取开头的协议名称
if(_mosquitto_read_string(&context->in_packet, &protocol_name)){
mqtt3_context_disconnect(db, context);
return 1;
}
if(!protocol_name){
mqtt3_context_disconnect(db, context);
return 3;
}
if(strcmp(protocol_name, PROTOCOL_NAME)){//协议名必须为"MQIsdp"
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Invalid protocol \"%s\" in CONNECT from %s.",
protocol_name, context->address);
}
_mosquitto_free(protocol_name);
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_PROTOCOL;
}//协议名只是为了检验是否为"MQIsdp"的，只后就没用啦
_mosquitto_free(protocol_name);
if(_mosquitto_read_byte(&context->in_packet, &protocol_version)){//8 个字节的协议号
mqtt3_context_disconnect(db, context);
return 1;
}
if((protocol_version&0x7F) != PROTOCOL_VERSION){//协议名必须是3版本
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_INFO, "Invalid protocol version %d in CONNECT from %s.",
protocol_version, context->address);
}
_mosquitto_send_connack(context, CONNACK_REFUSED_PROTOCOL_VERSION);
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_PROTOCOL;
}
if((protocol_version&0x80) == 0x80){//发送这种协议来的，就认为是bridge
context->is_bridge = true;
}
//下面读取各个标志
if(_mosquitto_read_byte(&context->in_packet, &connect_flags)){
mqtt3_context_disconnect(db, context);
return 1;
}
clean_session = connect_flags & 0x02;
will = connect_flags & 0x04;
will_qos = (connect_flags & 0x18) >> 3;
will_retain = connect_flags & 0x20;
password_flag = connect_flags & 0x40;
username_flag = connect_flags & 0x80;
context->clean_session = clean_session;
context->ping_t = 0;
if(_mosquitto_read_uint16(&context->in_packet, &(context->keepalive))){
mqtt3_context_disconnect(db, context);
return 1;
}
//客户端ID是必须有的，flags无法控制
if(_mosquitto_read_string(&context->in_packet, &client_id)){
mqtt3_context_disconnect(db, context);
return 1;
}
slen = strlen(client_id);
#ifdef WITH_STRICT_PROTOCOL
if(slen > 23 || slen == 0){
#else
if(slen == 0){
#endif
_mosquitto_free(client_id);
_mosquitto_send_connack(context, CONNACK_REFUSED_IDENTIFIER_REJECTED);
mqtt3_context_disconnect(db, context);
return 1;
}
context->id = client_id;
client_id = NULL;
/* clientid_prefixes check */
if(db->config->clientid_prefixes){//如果配置文件配置了客户端统一前缀clientid_prefixes，那么所有客户端昵称必须一致
if(strncmp(db->config->clientid_prefixes, context->id, strlen(db->config->clientid_prefixes))){
_mosquitto_send_connack(context, CONNACK_REFUSED_NOT_AUTHORIZED);
mqtt3_context_disconnect(db, context);
return MOSQ_ERR_SUCCESS;
}
}
if(will){//will指的是如果客户端意外断开连接，那么will Message内容的字符串消息会发布到Will Topic指代的地方
//申请一个message结构，待会填充到context->will上面
will_struct = _mosquitto_calloc(1, sizeof(struct mosquitto_message));
if(!will_struct){
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}
if(_mosquitto_read_string(&context->in_packet, &will_topic)){
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
if(strlen(will_topic) == 0){
/* FIXME - CONNACK_REFUSED_IDENTIFIER_REJECTED not really appropriate here. */
_mosquitto_send_connack(context, CONNACK_REFUSED_IDENTIFIER_REJECTED);
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
//由于需要记录长度，所以不能一次读取_mosquitto_read_string
if(_mosquitto_read_uint16(&context->in_packet, &will_payloadlen)){
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
will_payload = _mosquitto_malloc(will_payloadlen);
if(!will_payload){
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
rc = _mosquitto_read_bytes(&context->in_packet, will_payload, will_payloadlen);
if(rc){
mqtt3_context_disconnect(db, context);
rc = 1;
goto handle_connect_error;
}
//设置will-topic的相关信息，mqtt3_context_disconnect会用，判断连接不是主动断开的话会Publis一条消息
if(mosquitto_acl_check(db, context, will_topic, MOSQ_ACL_WRITE) != MOSQ_ERR_SUCCESS){
_mosquitto_send_connack(context, CONNACK_REFUSED_NOT_AUTHORIZED);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
context->will = will_struct;
will_struct = NULL ;//设置为空，避免handle_connect_error释放。放到context上面后续释放即可
context->will->topic = will_topic;
will_topic = NULL ;
if(will_payload){
context->will->payload = will_payload;
context->will->payloadlen = will_payloadlen;
will_payload = NULL ;
}else{
context->will->payload = NULL;
context->will->payloadlen = 0;
}
context->will->qos = will_qos;
context->will->retain = will_retain;
}
if(username_flag){//读取用户名密码
rc = _mosquitto_read_string(&context->in_packet, &username);
if(rc == MOSQ_ERR_SUCCESS){
if(password_flag){
rc = _mosquitto_read_string(&context->in_packet, &password);
if(rc == MOSQ_ERR_NOMEM){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}else if(rc == MOSQ_ERR_PROTOCOL){
/* Password flag given, but no password. Ignore. */
password_flag = 0;
}
}
}else if(rc == MOSQ_ERR_NOMEM){
rc = MOSQ_ERR_NOMEM;
goto handle_connect_error;
}else{
/* Username flag given, but no username. Ignore. */
username_flag = 0;
}
}
context->username = username;
context->password = password;
username = NULL; /* Avoid free() in error: below. */
password = NULL;
if(username_flag && password_flag){//如果发送了用户名密码，那么进行用户名密码校验
//放入待验证的客户端链表头部
struct _mosquitto_auth_list * tmpauth = _mosquitto_calloc(1, sizeof(struct _mosquitto_auth_list));
if(tmpauth == NULL){
_mosquitto_send_connack(context, CONNACK_REFUSED_SERVER_UNAVAILABLE);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
context->auth_result = CONNACK_REFUSED_NOT_AUTHORIZED ;
pthread_mutex_lock(&db->auth_list_mutex) ;
tmpauth->context = context ;
tmpauth->next = db->waiting_auth_list ;//如果db->waiting_auth_list为空这里也可以没事的
assert( context->sock != -1) ;
db->waiting_auth_list = tmpauth;
db->contexts[context->db_index] = NULL ;//暂时将这个链接从contexts中移除出来,待验证完成后，放入finished_auth_list
context->db_index = -1 ;
pthread_mutex_unlock(&db->auth_list_mutex) ;
//rc = mosquitto_unpwd_check(db, context->username, context->password);
return MOSQ_ERR_SUCCESS ;
}
//查看系统是否允许匿名使用
if(!username_flag && db->config->allow_anonymous == false){
_mosquitto_send_connack(context, CONNACK_REFUSED_NOT_AUTHORIZED);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_error;
}
//没有用户名，那么OK，继续后面的处理
rc = mqtt3_handle_post_check_unpwd( db, context) ;
return rc ;
handle_connect_error:
if(client_id) _mosquitto_free(client_id);
if(username) _mosquitto_free(username);
if(password) _mosquitto_free(password);
if(will_payload) _mosquitto_free(will_payload);
if(will_topic) _mosquitto_free(will_topic);
if(will_struct) _mosquitto_free(will_struct);
return rc;
}
int try_wakeup_finished_auth_connections( struct mosquitto_db *db ){
int i=0, dbidx = 0 ;
struct _mosquitto_auth_list * tofree = NULL;
pthread_mutex_lock(&db->auth_list_mutex) ;
struct _mosquitto_auth_list * tmpauth = db->finished_auth_list ;
db->finished_auth_list = NULL ;
while( tmpauth ){
//将链表每个元素还原到contexts数组里面
assert(tmpauth->context->sock != -1);
for(i = dbidx ; i < db->context_count; i++){
if(db->contexts[i] == NULL){
db->contexts[i] = tmpauth->context ;
break ;
}
}
if( i == db->context_count){
struct mosquitto **tmp_contexts = NULL;
tmp_contexts = _mosquitto_realloc(db->contexts, sizeof(struct mosquitto*)*(db->context_count+1));
if(tmp_contexts){
db->context_count += 1;
db->contexts = tmp_contexts;
db->contexts[i] = tmpauth->context;
}else{
//到这里，说明contexts[]数组不够了，而且relloac也失败，怎么办，只能丢掉这个连接了。但是下面并没有return -1,而且还去访问了。是个bug
// Out of memory
mqtt3_context_cleanup(NULL, tmpauth->context, true);
tmpauth = tmpauth->next ;
continue ;
}
}
//已经将这个连接放到contexts数组了。下面需要完成验证的后面部分
db->contexts[i]->db_index = i ;
mqtt3_handle_post_check_unpwd(db, db->contexts[i]) ;
dbidx = i+1 ;
tofree = tmpauth ;
tmpauth = tmpauth->next ;
_mosquitto_free( tofree ) ;
}
pthread_mutex_unlock(&db->auth_list_mutex) ;
return MOSQ_ERR_SUCCESS ;
}
int mqtt3_handle_post_check_unpwd( struct mosquitto_db *db, struct mosquitto *context ){
int rc = 0;
int i = 0;
struct _clientid_index_hash *find_cih;
struct _clientid_index_hash *new_cih;
struct _mosquitto_acl_user *acl_tail;
if(context->auth_result != CONNACK_ACCEPTED){//密码检查失败
_mosquitto_send_connack(context, CONNACK_REFUSED_BAD_USERNAME_PASSWORD);
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_SUCCESS;
goto handle_connect_post_error;
}
/* Find if this client already has an entry. This must be done *after* any security checks. */
HASH_FIND_STR(db->clientid_index_hash, context->id, find_cih);
if(find_cih){
i = find_cih->db_context_index;//这个客户端在db->contexts[]数组中的位置
/* Found a matching client */
if(db->contexts[i]->sock == -1){//这个肯定是断开连接后重练的
/* Client is reconnecting after a disconnect */
/* FIXME - does anything else need to be done here? */
}else{//这个是肿么回事?
/* Client is already connected, disconnect old version */
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_ERR, "Client %s already connected, closing old connection.", context->id);
}
}
//清除上一次连接的相关信息，进行初始化，设置为新连接的信息，这里需要考虑离线消息的问题
assert( db->contexts[i] != context ) ;
db->contexts[i]->clean_session = context->clean_session;
mqtt3_context_cleanup(db, db->contexts[i], false);//可能会关闭多点登陆的旧连接
db->contexts[i]->state = mosq_cs_connected;
db->contexts[i]->address = _mosquitto_strdup(context->address);
db->contexts[i]->sock = context->sock;
db->contexts[i]->listener = context->listener;
db->contexts[i]->last_msg_in = mosquitto_time();
db->contexts[i]->last_msg_out = mosquitto_time();
db->contexts[i]->keepalive = context->keepalive;
db->contexts[i]->pollfd_index = context->pollfd_index;
db->contexts[i]->id = _mosquitto_strdup(context->id);
if(context->username){
db->contexts[i]->username = _mosquitto_strdup(context->username);
}
if(context->password){
db->contexts[i]->password = _mosquitto_strdup(context->password);
}
_mosquitto_free(context->id);//参考mqtt3_context_cleanup，这里必须设置为空，否则db->clientid_index_hash会在那里被清楚
context->id = NULL;
context->sock = -1;
context->clean_session = 1 ;//让其待会在mosquitto_main_loop里面被清空
context->state = mosq_cs_disconnecting;
//上面这行是什么作用? 这个指针拿掉后，就没了，内存泄露？
//不是这样的，因为这个函数的上层调用方式为loop_handle_reads_writes()->_mosquitto_packet_read(db, db->contexts[i])
//也就是这里的context其实是db->contexts数组的某一项，因此这里由于已经知道client_id了，而且其曾经存在于某contexts项
//因此找到那一项后，将context上的数据拷贝到之前的记录中，然后将当前记录设置为sock = -1。state = mosq_cs_disconnecting
context = db->contexts[i];//交换使用旧的context
if(context->msgs){//旧的连接上还有数据挂着···
//所以需要将状态设置为一个OK的状态，重发上次的数据等，这里要小心重发的问题，别让客户端记录历史数据包
//里面的代码可能有bug
mqtt3_db_message_reconnect_reset(context);
}
}
// Add the client ID to the DB hash table here
//已经在里面的不需要增加进去了吧,不是，在mqtt3_context_cleanup里面又del掉了···还得加一次
new_cih = _mosquitto_malloc(sizeof(struct _clientid_index_hash));
if(!new_cih){
_mosquitto_log_printf(NULL, MOSQ_LOG_ERR, "Error: Out of memory.");
mqtt3_context_disconnect(db, context);
rc = MOSQ_ERR_NOMEM;
goto handle_connect_post_error;
}
new_cih->id = context->id;
new_cih->db_context_index = context->db_index;
HASH_ADD_KEYPTR(hh, db->clientid_index_hash, context->id, strlen(context->id), new_cih);
#ifdef WITH_PERSISTENCE
if(!context->clean_session){
db->persistence_changes++;
}
#endif
/* Associate user with its ACL, assuming we have ACLs loaded. */
if(db->acl_list){
acl_tail = db->acl_list;
while(acl_tail){
if(context->username){
if(acl_tail->username && !strcmp(context->username, acl_tail->username)){
context->acl_list = acl_tail;
break;
}
}else{
if(acl_tail->username == NULL){
context->acl_list = acl_tail;
break;
}
}
acl_tail = acl_tail->next;
}
}else{
context->acl_list = NULL;
}
if(db->config->connection_messages == true){
_mosquitto_log_printf(NULL, MOSQ_LOG_NOTICE, "New client connected from %s as %s (c%d, k%d).", context->address, context->id, context->clean_session, context->keepalive);
}
context->state = mosq_cs_connected;
//给客户端发送连接成功的CONNACK回包
return _mosquitto_send_connack(context, CONNACK_ACCEPTED);
handle_connect_post_error:
return rc;
}