/* Does a topic match a subscription? */
int mosquitto_topic_matches_sub(const char *sub, const char *topic, bool *result)
{
char *local_sub, *local_topic;
int slen, tlen;
int spos, tpos;
int rc;
bool multilevel_wildcard = false;
if(!sub || !topic || !result) return MOSQ_ERR_INVAL;
local_sub = _mosquitto_strdup(sub);
if(!local_sub) return MOSQ_ERR_NOMEM;
rc = _mosquitto_fix_sub_topic(&local_sub);
if(rc){
_mosquitto_free(local_sub);
return rc;
}
local_topic = _mosquitto_strdup(topic);
if(!local_topic){
_mosquitto_free(local_sub);
return MOSQ_ERR_NOMEM;
}
rc = _mosquitto_fix_sub_topic(&local_topic);
if(rc){
_mosquitto_free(local_sub);
_mosquitto_free(local_topic);
return rc;
}
slen = strlen(local_sub);
tlen = strlen(local_topic);
spos = 0;
tpos = 0;
while(spos < slen && tpos < tlen){
if(local_sub[spos] == local_topic[tpos]){
spos++;
tpos++;
if(spos == slen && tpos == tlen){
*result = true;
break;
}
}else{
if(local_sub[spos] == '+'){
spos++;
while(tpos < tlen && local_topic[tpos] != '/'){
tpos++;
}
if(tpos == tlen && spos == slen){
*result = true;
break;
}
}else if(local_sub[spos] == '#'){
multilevel_wildcard = true;
if(spos+1 != slen){
*result = false;
break;
}else{
*result = true;
break;
}
}else{
*result = false;
break;
}
}
if(tpos == tlen-1){
/* Check for e.g. foo matching foo/# */
if(spos == slen-3
&& local_sub[spos+1] == '/'
&& local_sub[spos+2] == '#'){
*result = true;
multilevel_wildcard = true;
break;
}
}
}
if(multilevel_wildcard == false && (tpos < tlen || spos < slen)){
*result = false;
}
_mosquitto_free(local_sub);
_mosquitto_free(local_topic);
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 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;
}
int mqtt3_handle_publish(struct mosquitto_db *db, struct mosquitto *context)
{
char *topic;
void *payload = NULL;
uint32_t payloadlen;
uint8_t dup, qos, retain;
uint16_t mid = 0;
int rc = 0;
uint8_t header = context->in_packet.command;
int res = 0;
struct mosquitto_msg_store *stored = NULL;
int len;
char *topic_mount;
char *topic_temp;
int i;
struct _mqtt3_bridge_topic *cur_topic;
bool match;
dup = (header & 0x08)>>3;
qos = (header & 0x06)>>1;
retain = (header & 0x01);
if(_mosquitto_read_string(&context->in_packet, &topic)) return 1;
if(strlen(topic) == 0){
/* Invalid publish topic, disconnect client. */
_mosquitto_free(topic);
return 1;
}
if(_mosquitto_fix_sub_topic(&topic)){
_mosquitto_free(topic);
return 1;
}
if(!strlen(topic)){
_mosquitto_free(topic);
return 1;
}
if(context->bridge && context->bridge->topics && context->bridge->topic_remapping){
for(i=0; i<context->bridge->topic_count; i++){
cur_topic = &context->bridge->topics[i];
if(cur_topic->remote_prefix || cur_topic->local_prefix){
/* Topic mapping required on this topic if the message matches */
rc = mosquitto_topic_matches_sub(cur_topic->remote_topic, topic, &match);
if(rc){
_mosquitto_free(topic);
return rc;
}
if(match){
if(cur_topic->remote_prefix){
/* This prefix needs removing. */
if(!strncmp(cur_topic->remote_prefix, topic, strlen(cur_topic->remote_prefix))){
topic_temp = _mosquitto_strdup(topic+strlen(cur_topic->remote_prefix));
if(!topic_temp){
_mosquitto_free(topic);
return MOSQ_ERR_NOMEM;
}
_mosquitto_free(topic);
topic = topic_temp;
}
}
if(cur_topic->local_prefix){
/* This prefix needs adding. */
len = strlen(topic) + strlen(cur_topic->local_prefix)+1;
topic_temp = _mosquitto_calloc(len+1, sizeof(char));
if(!topic_temp){
_mosquitto_free(topic);
return MOSQ_ERR_NOMEM;
}
snprintf(topic_temp, len, "%s%s", cur_topic->local_prefix, topic);
_mosquitto_free(topic);
topic = topic_temp;
}
break;
}
}
}
}
if(_mosquitto_topic_wildcard_len_check(topic) != MOSQ_ERR_SUCCESS){
/* Invalid publish topic, just swallow it. */
_mosquitto_free(topic);
return 1;
}
if(qos > 0){
if(_mosquitto_read_uint16(&context->in_packet, &mid)){
_mosquitto_free(topic);
return 1;
}
}
payloadlen = context->in_packet.remaining_length - context->in_packet.pos;
#ifdef WITH_SYS_TREE
g_pub_bytes_received += payloadlen;
#endif
if(context->listener && context->listener->mount_point){
len = strlen(context->listener->mount_point) + strlen(topic) + 1;
topic_mount = _mosquitto_calloc(len, sizeof(char));
if(!topic_mount){
_mosquitto_free(topic);
return MOSQ_ERR_NOMEM;
}
snprintf(topic_mount, len, "%s%s", context->listener->mount_point, topic);
_mosquitto_free(topic);
topic = topic_mount;
}
// 分配空间，写buffer
if(payloadlen){
if(db->config->message_size_limit && payloadlen > db->config->message_size_limit){
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "Dropped too large PUBLISH from %s (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))", context->id, dup, qos, retain, mid, topic, (long)payloadlen);
goto process_bad_message;
}
payload = _mosquitto_calloc(payloadlen+1, sizeof(uint8_t));
if(!payload){
_mosquitto_free(topic);
return 1;
}
if(_mosquitto_read_bytes(&context->in_packet, payload, payloadlen)){
_mosquitto_free(topic);
_mosquitto_free(payload);
return 1;
}
}
/* Check for topic access */
rc = mosquitto_acl_check(db, context, topic, MOSQ_ACL_WRITE);
if(rc == MOSQ_ERR_ACL_DENIED){
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "Denied PUBLISH from %s (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))", context->id, dup, qos, retain, mid, topic, (long)payloadlen);
goto process_bad_message;
}else if(rc != MOSQ_ERR_SUCCESS){
_mosquitto_free(topic);
if(payload) _mosquitto_free(payload);
return rc;
}
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "Received PUBLISH from %s (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))", context->id, dup, qos, retain, mid, topic, (long)payloadlen);
// TODO 对qos>0的情况再看下
if(qos > 0){
mqtt3_db_message_store_find(context, mid, &stored);
}
if(!stored){
dup = 0;
if(mqtt3_db_message_store(db, context->id, mid, topic, qos, payloadlen, payload, retain, &stored, 0)){
_mosquitto_free(topic);
if(payload) _mosquitto_free(payload);
return 1;
}
}else{
dup = 1;
}
switch(qos){
case 0:
if(mqtt3_db_messages_queue(db, context->id, topic, qos, retain, stored)) rc = 1;
break;
case 1:
if(mqtt3_db_messages_queue(db, context->id, topic, qos, retain, stored)) rc = 1;
if(_mosquitto_send_puback(context, mid)) rc = 1;
break;
case 2:
if(!dup){
res = mqtt3_db_message_insert(db, context, mid, mosq_md_in, qos, retain, stored);
}else{
res = 0;
}
/* mqtt3_db_message_insert() returns 2 to indicate dropped message
* due to queue. This isn't an error so don't disconnect them. */
if(!res){
if(_mosquitto_send_pubrec(context, mid)) rc = 1;
}else if(res == 1){
rc = 1;
}
break;
}
_mosquitto_free(topic);
if(payload) _mosquitto_free(payload);
return rc;
process_bad_message:
_mosquitto_free(topic);
if(payload) _mosquitto_free(payload);
switch(qos){
case 0:
return MOSQ_ERR_SUCCESS;
case 1:
return _mosquitto_send_puback(context, mid);
case 2:
mqtt3_db_message_store_find(context, mid, &stored);
if(!stored){
if(mqtt3_db_message_store(db, context->id, mid, NULL, qos, 0, NULL, false, &stored, 0)){
return 1;
}
res = mqtt3_db_message_insert(db, context, mid, mosq_md_in, qos, false, stored);
}else{
res = 0;
}
if(!res){
res = _mosquitto_send_pubrec(context, mid);
}
return res;
}
return 1;
}
int _mosquitto_handle_publish(struct mosquitto *mosq)
{
uint8_t header;
struct mosquitto_message_all *message;
int rc = 0;
uint16_t mid;
assert(mosq);
message = _mosquitto_calloc(1, sizeof(struct mosquitto_message_all));
if(!message) return MOSQ_ERR_NOMEM;
header = mosq->in_packet.command;
message->direction = mosq_md_in;
message->dup = (header & 0x08)>>3;
message->msg.qos = (header & 0x06)>>1;
message->msg.retain = (header & 0x01);
rc = _mosquitto_read_string(&mosq->in_packet, &message->msg.topic);
if(rc){
_mosquitto_message_cleanup(&message);
return rc;
}
rc = _mosquitto_fix_sub_topic(&message->msg.topic);
if(rc){
_mosquitto_message_cleanup(&message);
return rc;
}
if(!strlen(message->msg.topic)){
_mosquitto_message_cleanup(&message);
return MOSQ_ERR_PROTOCOL;
}
if(message->msg.qos > 0){
rc = _mosquitto_read_uint16(&mosq->in_packet, &mid);
if(rc){
_mosquitto_message_cleanup(&message);
return rc;
}
message->msg.mid = (int)mid;
}
message->msg.payloadlen = mosq->in_packet.remaining_length - mosq->in_packet.pos;
if(message->msg.payloadlen){
message->msg.payload = _mosquitto_calloc(message->msg.payloadlen+1, sizeof(uint8_t));
rc = _mosquitto_read_bytes(&mosq->in_packet, message->msg.payload, message->msg.payloadlen);
if(rc){
_mosquitto_message_cleanup(&message);
return rc;
}
}
_mosquitto_log_printf(mosq, MOSQ_LOG_DEBUG,
"Client %s received PUBLISH (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))",
mosq->id, message->dup, message->msg.qos, message->msg.retain,
message->msg.mid, message->msg.topic,
(long)message->msg.payloadlen);
message->timestamp = mosquitto_time();
switch(message->msg.qos){
case 0:
pthread_mutex_lock(&mosq->callback_mutex);
if(mosq->on_message){
mosq->in_callback = true;
mosq->on_message(mosq, mosq->userdata, &message->msg);
mosq->in_callback = false;
}
pthread_mutex_unlock(&mosq->callback_mutex);
_mosquitto_message_cleanup(&message);
return MOSQ_ERR_SUCCESS;
case 1:
rc = _mosquitto_send_puback(mosq, message->msg.mid);
pthread_mutex_lock(&mosq->callback_mutex);
if(mosq->on_message){
mosq->in_callback = true;
mosq->on_message(mosq, mosq->userdata, &message->msg);
mosq->in_callback = false;
}
pthread_mutex_unlock(&mosq->callback_mutex);
_mosquitto_message_cleanup(&message);
return rc;
case 2:
rc = _mosquitto_send_pubrec(mosq, message->msg.mid);
message->state = mosq_ms_wait_for_pubrel;
pthread_mutex_lock(&mosq->message_mutex);
_mosquitto_message_queue(mosq, message, true);
pthread_mutex_unlock(&mosq->message_mutex);
return rc;
default:
return MOSQ_ERR_PROTOCOL;
}
}
int mqtt3_handle_subscribe(mosquitto_db *db, mqtt3_context *context)
{
int rc = 0;
uint16_t mid;
char *sub;
uint8_t qos;
uint8_t *payload = NULL;
uint32_t payloadlen = 0;
if(!context) return 1;
mqtt3_log_printf(MOSQ_LOG_DEBUG, "Received SUBSCRIBE from %s", context->core.id);
/* FIXME - plenty of potential for memory leaks here */
if(_mosquitto_read_uint16(&context->core.in_packet, &mid)) return 1;
while(context->core.in_packet.pos < context->core.in_packet.remaining_length){
sub = NULL;
if(_mosquitto_read_string(&context->core.in_packet, &sub)){
if(sub) _mosquitto_free(sub);
if(payload) _mosquitto_free(payload);
return 1;
}
if(sub){
if(_mosquitto_read_byte(&context->core.in_packet, &qos)){
_mosquitto_free(sub);
if(payload) _mosquitto_free(payload);
return 1;
}
if(qos > 2){
mqtt3_log_printf(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)){
mqtt3_log_printf(MOSQ_LOG_INFO, "Empty subscription string from %s, disconnecting.",
context->address);
_mosquitto_free(sub);
if(payload) _mosquitto_free(payload);
return 1;
}
mqtt3_log_printf(MOSQ_LOG_DEBUG, "\t%s (QoS %d)", sub, qos);
mqtt3_sub_add(context, sub, qos, &db->subs);
if(mqtt3_retain_queue(db, context, sub, qos)) rc = 1;
_mosquitto_free(sub);
}
payload = _mosquitto_realloc(payload, payloadlen + 1);
payload[payloadlen] = qos;
payloadlen++;
}
if(mqtt3_raw_suback(context, mid, payloadlen, payload)) rc = 1;
_mosquitto_free(payload);
return rc;
}
int mqtt3_handle_publish(struct mosquitto_db *db, struct mosquitto *context)
{
char *topic;
void *payload = NULL;
uint32_t payloadlen;
uint8_t dup, qos, retain;
uint16_t mid = 0;
int rc = 0;
uint8_t header = context->in_packet.command;
int res = 0;
struct mosquitto_msg_store *stored = NULL;
int len;
char *topic_mount;
dup = (header & 0x08)>>3;
qos = (header & 0x06)>>1;
retain = (header & 0x01);
if(_mosquitto_read_string(&context->in_packet, &topic)) return 1;//读取TOPIC
if(strlen(topic) == 0){
/* Invalid publish topic, disconnect client. */
_mosquitto_free(topic);
return 1;
}
if(_mosquitto_fix_sub_topic(&topic)){//去掉topic上面多余的斜杠
_mosquitto_free(topic);
return 1;
}
if(!strlen(topic)){
_mosquitto_free(topic);
return 1;
}
//检查topic中是否有通配符，不允许publish到通配符地址
if(_mosquitto_topic_wildcard_len_check(topic) != MOSQ_ERR_SUCCESS){
/* Invalid publish topic, just swallow it. */
_mosquitto_free(topic);
return 1;
}
if(qos > 0){
if(_mosquitto_read_uint16(&context->in_packet, &mid)){
_mosquitto_free(topic);
return 1;
}
}
payloadlen = context->in_packet.remaining_length - context->in_packet.pos;
#ifdef WITH_SYS_TREE
g_pub_bytes_received += payloadlen;
#endif
if(context->listener && context->listener->mount_point){//追加一个配置的前缀
len = strlen(context->listener->mount_point) + strlen(topic) + 1;
topic_mount = _mosquitto_calloc(len, sizeof(char));
if(!topic_mount){
_mosquitto_free(topic);
return MOSQ_ERR_NOMEM;
}
snprintf(topic_mount, len, "%s%s", context->listener->mount_point, topic);
_mosquitto_free(topic);
topic = topic_mount;
}
if(payloadlen){//有数据部分，不是空,检查一下消息大小是否不合格，
if(db->config->message_size_limit && payloadlen > db->config->message_size_limit){
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "Dropped too large PUBLISH from %s (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))", context->id, dup, qos, retain, mid, topic, (long)payloadlen);
goto process_bad_message;
}
//读消息体
payload = _mosquitto_calloc(payloadlen+1, sizeof(uint8_t));
if(_mosquitto_read_bytes(&context->in_packet, payload, payloadlen)){
_mosquitto_free(topic);
return 1;
}
}
/* Check for topic access */
rc = mosquitto_acl_check(db, context, topic, MOSQ_ACL_WRITE);
if(rc == MOSQ_ERR_ACL_DENIED){
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "Denied PUBLISH from %s (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))", context->id, dup, qos, retain, mid, topic, (long)payloadlen);
goto process_bad_message;
}else if(rc != MOSQ_ERR_SUCCESS){
_mosquitto_free(topic);
if(payload) _mosquitto_free(payload);
return rc;
}
_mosquitto_log_printf(NULL, MOSQ_LOG_DEBUG, "Received PUBLISH from %s (d%d, q%d, r%d, m%d, '%s', ... (%ld bytes))", context->id, dup, qos, retain, mid, topic, (long)payloadlen);
if(qos > 0){//检查这个用户是否曾经发过这条消息,QOS大于0的消息ID只能出现一次
mqtt3_db_message_store_find(context, mid, &stored);
}
if(!stored){
dup = 0;//创建一个mosquitto_msg_store结构，放到db->msg_store的头部，结构里面存储了这条消息的所有信息
if(mqtt3_db_message_store(db, context->id, mid, topic, qos, payloadlen, payload, retain, &stored, 0)){
_mosquitto_free(topic);
if(payload) _mosquitto_free(payload);
return 1;
}
}else{
dup = 1;
}
switch(qos){
case 0:
if(mqtt3_db_messages_queue(db, context->id, topic, qos, retain, stored)) rc = 1;
break;
case 1:
//1级消息可以立即发布出去
if(mqtt3_db_messages_queue(db, context->id, topic, qos, retain, stored)) rc = 1;
//发送回包
if(_mosquitto_send_puback(context, mid)) rc = 1;
break;
case 2:
if(!dup){
//对于2级的消息，不能立即发布，得跟客户端协商后才行。文档：
//Log the message to persistent storage, do not make it available to interested
//parties yet, and return a PUBREC message to the sender.
//将一条消息插入到context->msg链表后面，设置相关的状态。然后记录这条消息给哪些人发送过等
res = mqtt3_db_message_insert(db, context, mid, mosq_md_in, qos, retain, stored);
}else{
res = 0;
}
/* mqtt3_db_message_insert() returns 2 to indicate dropped message
* due to queue. This isn't an error so don't disconnect them. */
if(!res){
if(_mosquitto_send_pubrec(context, mid)) rc = 1;
}else if(res == 1){
rc = 1;
}
break;
}
_mosquitto_free(topic);
if(payload) _mosquitto_free(payload);
return rc;
process_bad_message:
if(topic) _mosquitto_free(topic);
if(payload) _mosquitto_free(payload);
switch(qos){
case 0:
return MOSQ_ERR_SUCCESS;
case 1:
return _mosquitto_send_puback(context, mid);
case 2:
mqtt3_db_message_store_find(context, mid, &stored);
if(!stored){
if(mqtt3_db_message_store(db, context->id, mid, NULL, qos, 0, NULL, false, &stored, 0)){
return 1;
}
res = mqtt3_db_message_insert(db, context, mid, mosq_md_in, qos, false, stored);
}else{
res = 0;
}
if(!res){
res = _mosquitto_send_pubrec(context, mid);
}
return res;
}
return 1;
}
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;//SUB的返回包为SUBACK，结构为每一行代表对应的一个topic的QOS
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){
//SUBSCRIBE消息包括msgid，后面就是topic的列表,一个个取就行
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)){//1个byte的QOS，高位6为空
_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)){//把重复的斜杠去掉://////some//aa// -> some/aa/
_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);
//将当前的这个topic挂到订阅树里面，树的每一层为路径的一段,树的subs代表订阅的客户端链表，children代表子分支链表
rc2 = mqtt3_sub_add(db, context, sub, qos, &db->subs);
if(rc2 == MOSQ_ERR_SUCCESS){//订阅成功了
//下面需要检查一下这个topic上面是不是有retain保留消息需要发送给这个客户端,里面又会处理一遍订阅树，其实可以合并一起处理嘛
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);// 释放这个原始的字符串a/b/c
tmp_payload = _mosquitto_realloc(payload, payloadlen + 1);
if(tmp_payload){//这是要返回给客户端的QOS列表,一一对应
payload = tmp_payload;
payload[payloadlen] = qos;//QOS级别不变？如果本身的topic的级别不够的话怎么办
payloadlen++;
}else{
if(payload) _mosquitto_free(payload);
return MOSQ_ERR_NOMEM;
}
//搞定一条订阅消息，在订阅的topic上已经记录了这个连接，并且payload[]上面也增加了对应连接的qos准备返回
}
}
//发送SUBACK回包
if(_mosquitto_send_suback(context, mid, payloadlen, payload)) rc = 1;
_mosquitto_free(payload);
#ifdef WITH_PERSISTENCE
db->persistence_changes++;
#endif
return rc;
}