ngx_tcp_session.c

#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
#include <ngx_tcp.h>


static void ngx_tcp_init_session(ngx_connection_t *c);
static void ngx_tcp_set_session_socket(ngx_tcp_session_t *s);
static void ngx_tcp_process_session(ngx_connection_t *c);

#if (NGX_TCP_SSL)
static void ngx_tcp_ssl_init_connection(ngx_ssl_t *ssl, ngx_connection_t *c);
static void ngx_tcp_ssl_handshake_handler(ngx_connection_t *c);
#endif


void
ngx_tcp_init_connection(ngx_connection_t *c)
{
    ngx_uint_t            i;
    ngx_tcp_port_t       *port;
    struct sockaddr      *sa;
    struct sockaddr_in   *sin;
    ngx_tcp_log_ctx_t    *ctx;
    ngx_tcp_in_addr_t    *addr;
    ngx_tcp_session_t    *s;
    ngx_tcp_addr_conf_t  *addr_conf;
#if (NGX_HAVE_INET6)
    struct sockaddr_in6  *sin6;
    ngx_tcp_in6_addr_t   *addr6;
#endif


    /* find the server configuration for the address:port */

    /* AF_INET only */

    port = c->listening->servers;

    if (port->naddrs > 1) {

        /*
         * There are several addresses on this port and one of them
         * is the "*:port" wildcard so getsockname() is needed to determine
         * the server address.
         *
         * AcceptEx() already gave this address.
         */

        if (ngx_connection_local_sockaddr(c, NULL, 0) != NGX_OK) {
            ngx_tcp_close_connection(c);
            return;
        }

        sa = c->local_sockaddr;

        switch (sa->sa_family) {

#if (NGX_HAVE_INET6)
        case AF_INET6:
            sin6 = (struct sockaddr_in6 *) sa;

            addr6 = port->addrs;

            /* the last address is "*" */

            for (i = 0; i < port->naddrs - 1; i++) {
                if (ngx_memcmp(&addr6[i].addr6, &sin6->sin6_addr, 16) == 0) {
                    break;
                }
            }

            addr_conf = &addr6[i].conf;

            break;
#endif

        default: /* AF_INET */
            sin = (struct sockaddr_in *) sa;

            addr = port->addrs;

            /* the last address is "*" */

            for (i = 0; i < port->naddrs - 1; i++) {
                if (addr[i].addr == sin->sin_addr.s_addr) {
                    break;
                }
            }

            addr_conf = &addr[i].conf;

            break;
        }

    } else {
        switch (c->local_sockaddr->sa_family) {

#if (NGX_HAVE_INET6)
        case AF_INET6:
            addr6 = port->addrs;
            addr_conf = &addr6[0].conf;
            break;
#endif

        default: /* AF_INET */
            addr = port->addrs;
            addr_conf = &addr[0].conf;
            break;
        }
    }

    s = ngx_pcalloc(c->pool, sizeof(ngx_tcp_session_t));
    if (s == NULL) {
        ngx_tcp_close_connection(c);
        return;
    }

    if (addr_conf->default_ctx) {
        s->main_conf = addr_conf->default_ctx->main_conf;
        s->srv_conf = addr_conf->default_ctx->srv_conf;
    }
    else {
        s->main_conf = addr_conf->ctx->main_conf;
        s->srv_conf = addr_conf->ctx->srv_conf;
    }

    s->addr_text = &addr_conf->addr_text;

    c->data = s;
    s->connection = c;

    ngx_log_error(NGX_LOG_INFO, c->log, 0, "*%ui client %V connected to %V",
                  c->number, &c->addr_text, s->addr_text);

    ctx = ngx_palloc(c->pool, sizeof(ngx_tcp_log_ctx_t));
    if (ctx == NULL) {
        ngx_tcp_close_connection(c);
        return;
    }

    ctx->client = &c->addr_text;
    ctx->session = s;

    c->log->connection = c->number;
    c->log->handler = ngx_tcp_log_error;
    c->log->data = ctx;
    c->log->action = "nginx tcp module init connection";

    c->log_error = NGX_ERROR_INFO;

#if (NGX_TCP_SSL)

    {
    ngx_tcp_ssl_srv_conf_t  *sscf;

    sscf = ngx_tcp_get_module_srv_conf(s, ngx_tcp_ssl_module);
    if (sscf->enable || addr_conf->ssl) {

        if (c->ssl == NULL) {

            c->log->action = "SSL handshaking";

            if (addr_conf->ssl && sscf->ssl.ctx == NULL) {
                ngx_log_error(NGX_LOG_ERR, c->log, 0,
                              "no \"ssl_certificate\" is defined "
                              "in server listening on SSL port");
                ngx_tcp_close_connection(c);
                return;
            }

            ngx_tcp_ssl_init_connection(&sscf->ssl, c);
            return;
        }
    }
    }

#endif

    ngx_tcp_init_session(c);
}


#if (NGX_TCP_SSL)

static void
ngx_tcp_ssl_init_connection(ngx_ssl_t *ssl, ngx_connection_t *c)
{
    ngx_tcp_session_t        *s;
    ngx_tcp_core_srv_conf_t  *cscf;

    if (ngx_ssl_create_connection(ssl, c, NGX_SSL_BUFFER) == NGX_ERROR) {
        ngx_tcp_close_connection(c);
        return;
    }

    if (ngx_ssl_handshake(c) == NGX_AGAIN) {

        s = c->data;

        cscf = ngx_tcp_get_module_srv_conf(s, ngx_tcp_core_module);

        ngx_add_timer(c->read, cscf->timeout);

        c->ssl->handler = ngx_tcp_ssl_handshake_handler;

        return;
    }

    ngx_tcp_ssl_handshake_handler(c);
}


static void
ngx_tcp_ssl_handshake_handler(ngx_connection_t *c)
{
    if (c->ssl->handshaked) {

        c->read->ready = 0;

        ngx_tcp_init_session(c);
        return;
    }

    ngx_tcp_close_connection(c);
}

#endif


static void
ngx_tcp_init_session(ngx_connection_t *c)
{
    ngx_time_t               *tp;
    ngx_tcp_session_t        *s;
    ngx_tcp_core_srv_conf_t  *cscf;

    s = c->data;

    s->signature = NGX_TCP_MODULE;
    s->pool = c->pool;

    cscf = ngx_tcp_get_module_srv_conf(s, ngx_tcp_core_module);
    if (cscf == NULL) {
        ngx_tcp_finalize_session(s);
        return;
    }

    s->ctx = ngx_pcalloc(s->pool, sizeof(void *) * ngx_tcp_max_module);
    if (s->ctx == NULL) {
        ngx_tcp_finalize_session(s);
        return;
    }

    tp = ngx_timeofday();
    s->start_sec = tp->sec;
    s->start_msec = tp->msec;

    s->bytes_read = 0;
    s->bytes_write = 0;

    ngx_tcp_set_session_socket(s);

    ngx_tcp_process_session(c);
}


static void 
ngx_tcp_set_session_socket(ngx_tcp_session_t *s) 
{
    int                       keepalive;
    int                       tcp_nodelay;
    ngx_tcp_core_srv_conf_t  *cscf;

    cscf = ngx_tcp_get_module_srv_conf(s, ngx_tcp_core_module);

    if (cscf->so_keepalive) {
        keepalive = 1;

        if (setsockopt(s->connection->fd, SOL_SOCKET, SO_KEEPALIVE,
                       (const void *) &keepalive, sizeof(int)) == -1)
        {
            ngx_log_error(NGX_LOG_ALERT, s->connection->log, ngx_socket_errno,
                          "setsockopt(SO_KEEPALIVE) failed");
        }
    }

    if (cscf->tcp_nodelay) {
        tcp_nodelay = 1;
        if (setsockopt(s->connection->fd, IPPROTO_TCP, TCP_NODELAY,
                       (const void *) &tcp_nodelay, sizeof(int))
            == -1)
        {
            ngx_log_error(NGX_LOG_ALERT, s->connection->log, ngx_socket_errno,
                          "setsockopt(TCP_NODELAY) failed");
        }

        s->connection->tcp_nodelay = NGX_TCP_NODELAY_SET;
    }
}


static void
ngx_tcp_process_session(ngx_connection_t *c)
{
    ngx_tcp_session_t         *s;
    ngx_tcp_core_srv_conf_t   *cscf;

    s = c->data;

    cscf = ngx_tcp_get_module_srv_conf(s, ngx_tcp_core_module);

    /* process the ACL */
    if (ngx_tcp_access_handler(s) == NGX_ERROR) {
        ngx_tcp_finalize_session(s);
        return;
    }

    cscf->protocol->init_session(s);
}


void
ngx_tcp_send(ngx_event_t *wev)
{
    ngx_int_t                  n;
    ngx_connection_t          *c;
    ngx_tcp_session_t         *s;
    ngx_tcp_core_srv_conf_t   *cscf;

    c = wev->data;
    s = c->data;

    if (wev->timedout) {
        ngx_log_error(NGX_LOG_INFO, c->log, NGX_ETIMEDOUT, "client timed out");
        c->timedout = 1;
        ngx_tcp_close_connection(c);
        return;
    }

    if (s->out.len == 0) {
        if (ngx_handle_write_event(c->write, 0) != NGX_OK) {
            ngx_tcp_close_connection(c);
        }

        return;
    }

    n = c->send(c, s->out.data, s->out.len);
    ngx_log_debug1(NGX_LOG_DEBUG_TCP, wev->log, 0, "nginx tcp send:%d", n);

    if (n > 0) {
        s->out.len -= n;

        if (wev->timer_set) {
            ngx_del_timer(wev);
        }

        if (s->quit) {
            ngx_tcp_close_connection(c);
            return;
        }

        return;
    }

    if (n == NGX_ERROR) {
        ngx_tcp_close_connection(c);
        return;
    }

    /* n == NGX_AGAIN */

    cscf = ngx_tcp_get_module_srv_conf(s, ngx_tcp_core_module);

    ngx_add_timer(c->write, cscf->timeout);

    if (ngx_handle_write_event(c->write, 0) != NGX_OK) {
        ngx_tcp_close_connection(c);
        return;
    }
}


void
ngx_tcp_session_internal_server_error(ngx_tcp_session_t *s)
{
    ngx_tcp_core_srv_conf_t  *cscf;

    cscf = ngx_tcp_get_module_srv_conf(s, ngx_tcp_core_module);

    s->out = cscf->protocol->internal_server_error;
    s->quit = 1;

    ngx_tcp_send(s->connection->write);
}


void 
ngx_tcp_finalize_session(ngx_tcp_session_t *s)
{
    ngx_connection_t *c;
    ngx_tcp_cleanup_t *cln;

    c = s->connection;

    ngx_tcp_log_handler(s);

    ngx_log_debug1(NGX_LOG_DEBUG_TCP, c->log, 0,
                   "close tcp session: %d", c->fd);

    for (cln = s->cleanup; cln; cln = cln->next) {
        if (cln->handler) {
            cln->handler(cln->data);
            cln->handler = NULL;
        }
    }

    ngx_tcp_close_connection(c);

    return;
}


void
ngx_tcp_close_connection(ngx_connection_t *c)
{
    ngx_pool_t  *pool;

    ngx_log_debug1(NGX_LOG_DEBUG_TCP, c->log, 0,
                   "close tcp connection: %d", c->fd);

#if (NGX_TCP_SSL)

    if (c->ssl) {
        if (ngx_ssl_shutdown(c) == NGX_AGAIN) {
            c->ssl->handler = ngx_tcp_close_connection;
            return;
        }
    }

#endif

#if (NGX_STAT_STUB)
    (void) ngx_atomic_fetch_add(ngx_stat_active, -1);
#endif

    c->destroyed = 1;

    pool = c->pool;

    ngx_close_connection(c);

    ngx_destroy_pool(pool);
}


u_char *
ngx_tcp_log_error(ngx_log_t *log, u_char *buf, size_t len)
{
    u_char              *p;
    ngx_tcp_session_t   *s;
    ngx_tcp_log_ctx_t   *ctx;

    p = buf;

    if (log->action) {
        p = ngx_snprintf(p, len + (buf - p), " while %s", log->action);
    }

    ctx = log->data;

    p = ngx_snprintf(p, len + (buf - p), ", client: %V", ctx->client);

    s = ctx->session;

    if (s == NULL) {
        return p;
    }

    p = ngx_snprintf(p, len + (buf - p), ", server: %V", s->addr_text);

    if (s->upstream) {
        if (s->upstream->peer.connection) {
            p = ngx_snprintf(p, len + (buf - p), ", upstream: %V", s->upstream->peer.name);
        }
    }

    return p;
}


ngx_tcp_cleanup_t *
ngx_tcp_cleanup_add(ngx_tcp_session_t *s, size_t size)
{
    ngx_tcp_cleanup_t  *cln;

    cln = ngx_palloc(s->pool, sizeof(ngx_tcp_cleanup_t));
    if (cln == NULL) {
        return NULL;
    }

    if (size) {
        cln->data = ngx_palloc(s->pool, size);
        if (cln->data == NULL) {
            return NULL;
        }

    } else {
        cln->data = NULL;
    }

    cln->handler = NULL;
    cln->next = s->cleanup;

    s->cleanup = cln;

    ngx_log_debug1(NGX_LOG_DEBUG_TCP, s->connection->log, 0,
                   "tcp cleanup add: %p", cln);

    return cln;
}