ngx_gp_handler.c

/*
 * Copyright (C) Igor Sysoev
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
#include "ngx_gp.h"


static void ngx_gp_init_session(ngx_connection_t *c);

#if (NGX_GP_SSL)
static void ngx_gp_ssl_init_connection(ngx_ssl_t *ssl, ngx_connection_t *c);
static void ngx_gp_ssl_handshake_handler(ngx_connection_t *c);
#endif


void
ngx_gp_init_connection(ngx_connection_t *c)
{
    ngx_uint_t             i;
    ngx_gp_port_t       *port;
    struct sockaddr       *sa;
    struct sockaddr_in    *sin;
    ngx_gp_log_ctx_t    *ctx;
    ngx_gp_in_addr_t    *addr;
    ngx_gp_session_t    *s;
    ngx_gp_addr_conf_t  *addr_conf;
#if (NGX_HAVE_INET6)
    struct sockaddr_in6   *sin6;
    ngx_gp_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_gp_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_gp_session_t));
    if (s == NULL) {
        ngx_gp_close_connection(c);
        return;
    }

    s->main_conf = addr_conf->ctx->main_conf;
    s->srv_conf = addr_conf->ctx->srv_conf;

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

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

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

    c->log->connection = c->number;
    c->log->handler = ngx_gp_log_error;
    c->log->data = ctx;
    c->log->action = "sending client greeting line";

    c->log_error = NGX_ERROR_INFO;

#if (NGX_GP_SSL)
    {
    ngx_gp_ssl_conf_t  *sslcf;

    sslcf = ngx_gp_get_module_srv_conf(s, ngx_gp_ssl_module);

    if (sslcf->enable) {
        c->log->action = "SSL handshaking";

        ngx_gp_ssl_init_connection(&sslcf->ssl, c);
        return;
    }

    if (addr_conf->ssl) {

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

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

        ngx_gp_ssl_init_connection(&sslcf->ssl, c);
        return;
    }

    }
#endif

    ngx_gp_init_session(c);
}


#if (NGX_GP_SSL)

void
ngx_gp_starttls_handler(ngx_event_t *rev)
{
    ngx_connection_t     *c;
    ngx_gp_session_t   *s;
    ngx_gp_ssl_conf_t  *sslcf;

    c = rev->data;
    s = c->data;
    s->starttls = 1;

    c->log->action = "in starttls state";

    sslcf = ngx_gp_get_module_srv_conf(s, ngx_gp_ssl_module);

    ngx_gp_ssl_init_connection(&sslcf->ssl, c);
}


static void
ngx_gp_ssl_init_connection(ngx_ssl_t *ssl, ngx_connection_t *c)
{
    ngx_gp_session_t        *s;
    ngx_gp_core_srv_conf_t  *cscf;

    if (ngx_ssl_create_connection(ssl, c, 0) == NGX_ERROR) {
        ngx_gp_close_connection(c);
        return;
    }

    if (ngx_ssl_handshake(c) == NGX_AGAIN) {

        s = c->data;

        cscf = ngx_gp_get_module_srv_conf(s, ngx_gp_core_module);

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

        c->ssl->handler = ngx_gp_ssl_handshake_handler;

        return;
    }

    ngx_gp_ssl_handshake_handler(c);
}


static void
ngx_gp_ssl_handshake_handler(ngx_connection_t *c)
{
    ngx_gp_session_t        *s;
    ngx_gp_core_srv_conf_t  *cscf;

    if (c->ssl->handshaked) {

        s = c->data;

        if (s->starttls) {
            cscf = ngx_gp_get_module_srv_conf(s, ngx_gp_core_module);

            c->read->handler = cscf->protocol->init_protocol;
            c->write->handler = ngx_gp_send;

            cscf->protocol->init_protocol(c->read);

            return;
        }

        c->read->ready = 0;

        ngx_gp_init_session(c);
        return;
    }

    ngx_gp_close_connection(c);
}

#endif


static void
ngx_gp_init_session(ngx_connection_t *c)
{
    ngx_gp_session_t        *s;
    ngx_gp_core_srv_conf_t  *cscf;

    s = c->data;

    cscf = ngx_gp_get_module_srv_conf(s, ngx_gp_core_module);

    s->protocol = cscf->protocol->type;

    s->ctx = ngx_pcalloc(c->pool, sizeof(void *) * ngx_gp_max_module);
    if (s->ctx == NULL) {
        ngx_gp_session_internal_server_error(s);
        return;
    }

    c->write->handler = ngx_gp_send;

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

void
ngx_gp_send(ngx_event_t *wev)
{
    ngx_int_t                  n;
    ngx_connection_t          *c;
    ngx_gp_session_t        *s;
    ngx_gp_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_gp_close_connection(c);
        return;
    }

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

        return;
    }

    n = c->send(c, s->out.data, s->out.len);

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

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

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

        if (s->blocked) {
            c->read->handler(c->read);
        }

        return;
    }

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

    /* n == NGX_AGAIN */

    cscf = ngx_gp_get_module_srv_conf(s, ngx_gp_core_module);

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

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


ngx_int_t
ngx_gp_read_command(ngx_gp_session_t *s, ngx_connection_t *c)
{
    ssize_t                    n;
    ngx_int_t                  rc;
    ngx_str_t                  l;
    ngx_gp_core_srv_conf_t  *cscf;

    n = c->recv(c, s->buffer->last, s->buffer->end - s->buffer->last);

    if (n == NGX_ERROR || n == 0) {
        ngx_gp_close_connection(c);
        return NGX_ERROR;
    }

    if (n > 0) {
        s->buffer->last += n;
    }

    if (n == NGX_AGAIN) {
        if (ngx_handle_read_event(c->read, 0) != NGX_OK) {
            ngx_gp_session_internal_server_error(s);
            return NGX_ERROR;
        }

        return NGX_AGAIN;
    }

    cscf = ngx_gp_get_module_srv_conf(s, ngx_gp_core_module);

    rc = cscf->protocol->parse_command(s);

    if (rc == NGX_AGAIN) {

        if (s->buffer->last < s->buffer->end) {
            return rc;
        }

        l.len = s->buffer->last - s->buffer->start;
        l.data = s->buffer->start;

        ngx_log_error(NGX_LOG_INFO, c->log, 0,
                      "client sent too long command \"%V\"", &l);

        s->quit = 1;

        return NGX_GP_PARSE_INVALID_COMMAND;
    }

    if (rc == NGX_GP_PARSE_INVALID_COMMAND) {
        return rc;
    }

    if (rc == NGX_ERROR) {
        ngx_gp_close_connection(c);
        return NGX_ERROR;
    }

    return NGX_OK;
}


void
ngx_gp_auth(ngx_gp_session_t *s, ngx_connection_t *c)
{
    s->buffer->pos = s->buffer->start;
    s->buffer->last = s->buffer->start;
    s->state = 0;

    if (c->read->timer_set) {
        ngx_del_timer(c->read);
    }
}


void
ngx_gp_session_internal_server_error(ngx_gp_session_t *s)
{
    ngx_gp_core_srv_conf_t  *cscf;

    cscf = ngx_gp_get_module_srv_conf(s, ngx_gp_core_module);

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

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


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

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

#if (NGX_GP_SSL)

    if (c->ssl) {
        if (ngx_ssl_shutdown(c) == NGX_AGAIN) {
            c->ssl->handler = ngx_gp_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_gp_log_error(ngx_log_t *log, u_char *buf, size_t len)
{
    u_char              *p;
    ngx_gp_log_ctx_t  *ctx;

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

    ctx = log->data;

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

    return p;
}