static ngx_int_t
ngx_http_limit_conn_handler(ngx_http_request_t *r)
{
syslog(LOG_INFO, "[%s:%s:%d]", __FILE__, __func__, __LINE__);
size_t len, n;
uint32_t hash;
ngx_uint_t i;
ngx_slab_pool_t *shpool;
ngx_rbtree_node_t *node;
ngx_pool_cleanup_t *cln;
ngx_http_variable_value_t *vv;
ngx_http_limit_conn_ctx_t *ctx;
ngx_http_limit_conn_node_t *lc;
ngx_http_limit_conn_conf_t *lccf;
ngx_http_limit_conn_limit_t *limits;
ngx_http_limit_conn_cleanup_t *lccln;
if (r->main->limit_conn_set) {
return NGX_DECLINED;
}
lccf = ngx_http_get_module_loc_conf(r, ngx_http_limit_conn_module);
limits = lccf->limits.elts;
for (i = 0; i < lccf->limits.nelts; i++) {
ctx = limits[i].shm_zone->data;
vv = ngx_http_get_indexed_variable(r, ctx->index);
if (vv == NULL || vv->not_found) {
continue;
}
len = vv->len;
if (len == 0) {
continue;
}
if (len > 255) {
ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
"the value of the \"%V\" variable "
"is more than 255 bytes: \"%v\"",
&ctx->var, vv);
continue;
}
r->main->limit_conn_set = 1;
hash = ngx_crc32_short(vv->data, len);
shpool = (ngx_slab_pool_t *) limits[i].shm_zone->shm.addr;
ngx_shmtx_lock(&shpool->mutex);
node = ngx_http_limit_conn_lookup(ctx->rbtree, vv, hash);
if (node == NULL) {
n = offsetof(ngx_rbtree_node_t, color)
+ offsetof(ngx_http_limit_conn_node_t, data)
+ len;
node = ngx_slab_alloc_locked(shpool, n);
if (node == NULL) {
ngx_shmtx_unlock(&shpool->mutex);
ngx_http_limit_conn_cleanup_all(r->pool);
return NGX_HTTP_SERVICE_UNAVAILABLE;
}
lc = (ngx_http_limit_conn_node_t *) &node->color;
node->key = hash;
lc->len = (u_char) len;
lc->conn = 1;
ngx_memcpy(lc->data, vv->data, len);
ngx_rbtree_insert(ctx->rbtree, node);
} else {
lc = (ngx_http_limit_conn_node_t *) &node->color;
if ((ngx_uint_t) lc->conn >= limits[i].conn) {
ngx_shmtx_unlock(&shpool->mutex);
ngx_log_error(lccf->log_level, r->connection->log, 0,
"limiting connections by zone \"%V\"",
&limits[i].shm_zone->shm.name);
ngx_http_limit_conn_cleanup_all(r->pool);
return NGX_HTTP_SERVICE_UNAVAILABLE;
}
lc->conn++;
}
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"limit conn: %08XD %d", node->key, lc->conn);
ngx_shmtx_unlock(&shpool->mutex);
cln = ngx_pool_cleanup_add(r->pool,
sizeof(ngx_http_limit_conn_cleanup_t));
if (cln == NULL) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
cln->handler = ngx_http_limit_conn_cleanup;
lccln = cln->data;
lccln->shm_zone = limits[i].shm_zone;
lccln->node = node;
}
return NGX_DECLINED;
}
static ngx_int_t
ngx_http_limit_conn_handler(ngx_http_request_t *r)
{
size_t n;
uint32_t hash;
ngx_str_t key;
ngx_uint_t i;
ngx_slab_pool_t *shpool;
ngx_rbtree_node_t *node;
ngx_pool_cleanup_t *cln;
ngx_http_limit_conn_ctx_t *ctx;
ngx_http_limit_conn_node_t *lc;
ngx_http_limit_conn_conf_t *lccf;
ngx_http_limit_conn_limit_t *limits;
ngx_http_limit_conn_cleanup_t *lccln;
if (r->main->limit_conn_set)
{
return NGX_DECLINED;
}
lccf = ngx_http_get_module_loc_conf(r, ngx_http_limit_conn_module);
limits = lccf->limits.elts;
for (i = 0; i < lccf->limits.nelts; i++)
{
ctx = limits[i].shm_zone->data;
if (ngx_http_complex_value(r, &ctx->key, &key) != NGX_OK)
{
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
if (key.len == 0)
{
continue;
}
if (key.len > 255)
{
ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
"the value of the \"%V\" key "
"is more than 255 bytes: \"%V\"",
&ctx->key.value, &key);
continue;
}
r->main->limit_conn_set = 1;
hash = ngx_crc32_short(key.data, key.len);
shpool = (ngx_slab_pool_t *) limits[i].shm_zone->shm.addr;
ngx_shmtx_lock(&shpool->mutex);
node = ngx_http_limit_conn_lookup(ctx->rbtree, &key, hash);
if (node == NULL)
{
n = offsetof(ngx_rbtree_node_t, color)
+ offsetof(ngx_http_limit_conn_node_t, data)
+ key.len;
node = ngx_slab_alloc_locked(shpool, n);
if (node == NULL)
{
ngx_shmtx_unlock(&shpool->mutex);
ngx_http_limit_conn_cleanup_all(r->pool);
return lccf->status_code;
}
lc = (ngx_http_limit_conn_node_t *) &node->color;
node->key = hash;
lc->len = (u_char) key.len;
lc->conn = 1;
ngx_memcpy(lc->data, key.data, key.len);
ngx_rbtree_insert(ctx->rbtree, node);
}
else
{
lc = (ngx_http_limit_conn_node_t *) &node->color;
if ((ngx_uint_t) lc->conn >= limits[i].conn)
{
ngx_shmtx_unlock(&shpool->mutex);
ngx_log_error(lccf->log_level, r->connection->log, 0,
"limiting connections by zone \"%V\"",
&limits[i].shm_zone->shm.name);
ngx_http_limit_conn_cleanup_all(r->pool);
return lccf->status_code;
}
lc->conn++;
}
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"limit conn: %08XD %d", node->key, lc->conn);
ngx_shmtx_unlock(&shpool->mutex);
cln = ngx_pool_cleanup_add(r->pool,
sizeof(ngx_http_limit_conn_cleanup_t));
if (cln == NULL)
{
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
cln->handler = ngx_http_limit_conn_cleanup;
lccln = cln->data;
lccln->shm_zone = limits[i].shm_zone;
lccln->node = node;
}
return NGX_DECLINED;
}
