view src/event/ngx_event_udp.c @ 7352:0de0b16a551c

SSL: corrected SSL_ERROR_WANT_WRITE / SSL_ERROR_WANT_READ logging. While SSL_read() most likely to return SSL_ERROR_WANT_WRITE (and SSL_write() accordingly SSL_ERROR_WANT_READ) during an SSL renegotiation, it is not necessary mean that a renegotiation was started. In particular, it can never happen during a renegotiation or can happen multiple times during a renegotiation. Because of the above, misleading "peer started SSL renegotiation" info messages were replaced with "SSL_read: want write" and "SSL_write: want read" debug ones. Additionally, "SSL write handler" and "SSL read handler" are now logged by the SSL write and read handlers, to make it easier to understand that temporary SSL handlers are called instead of normal handlers.
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 10 Sep 2018 18:57:19 +0300
parents d27aa9060c95
children 27559d4a5151
line wrap: on
line source


/*
 * Copyright (C) Roman Arutyunyan
 * Copyright (C) Nginx, Inc.
 */


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


#if !(NGX_WIN32)

struct ngx_udp_connection_s {
    ngx_rbtree_node_t   node;
    ngx_connection_t   *connection;
    ngx_buf_t          *buffer;
};


static void ngx_close_accepted_udp_connection(ngx_connection_t *c);
static ssize_t ngx_udp_shared_recv(ngx_connection_t *c, u_char *buf,
    size_t size);
static ngx_int_t ngx_insert_udp_connection(ngx_connection_t *c);
static void ngx_delete_udp_connection(void *data);
static ngx_connection_t *ngx_lookup_udp_connection(ngx_listening_t *ls,
    struct sockaddr *sockaddr, socklen_t socklen,
    struct sockaddr *local_sockaddr, socklen_t local_socklen);


void
ngx_event_recvmsg(ngx_event_t *ev)
{
    ssize_t            n;
    ngx_buf_t          buf;
    ngx_log_t         *log;
    ngx_err_t          err;
    socklen_t          socklen, local_socklen;
    ngx_event_t       *rev, *wev;
    struct iovec       iov[1];
    struct msghdr      msg;
    ngx_sockaddr_t     sa, lsa;
    struct sockaddr   *sockaddr, *local_sockaddr;
    ngx_listening_t   *ls;
    ngx_event_conf_t  *ecf;
    ngx_connection_t  *c, *lc;
    static u_char      buffer[65535];

#if (NGX_HAVE_MSGHDR_MSG_CONTROL)

#if (NGX_HAVE_IP_RECVDSTADDR)
    u_char             msg_control[CMSG_SPACE(sizeof(struct in_addr))];
#elif (NGX_HAVE_IP_PKTINFO)
    u_char             msg_control[CMSG_SPACE(sizeof(struct in_pktinfo))];
#endif

#if (NGX_HAVE_INET6 && NGX_HAVE_IPV6_RECVPKTINFO)
    u_char             msg_control6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
#endif

#endif

    if (ev->timedout) {
        if (ngx_enable_accept_events((ngx_cycle_t *) ngx_cycle) != NGX_OK) {
            return;
        }

        ev->timedout = 0;
    }

    ecf = ngx_event_get_conf(ngx_cycle->conf_ctx, ngx_event_core_module);

    if (!(ngx_event_flags & NGX_USE_KQUEUE_EVENT)) {
        ev->available = ecf->multi_accept;
    }

    lc = ev->data;
    ls = lc->listening;
    ev->ready = 0;

    ngx_log_debug2(NGX_LOG_DEBUG_EVENT, ev->log, 0,
                   "recvmsg on %V, ready: %d", &ls->addr_text, ev->available);

    do {
        ngx_memzero(&msg, sizeof(struct msghdr));

        iov[0].iov_base = (void *) buffer;
        iov[0].iov_len = sizeof(buffer);

        msg.msg_name = &sa;
        msg.msg_namelen = sizeof(ngx_sockaddr_t);
        msg.msg_iov = iov;
        msg.msg_iovlen = 1;

#if (NGX_HAVE_MSGHDR_MSG_CONTROL)

        if (ls->wildcard) {

#if (NGX_HAVE_IP_RECVDSTADDR || NGX_HAVE_IP_PKTINFO)
            if (ls->sockaddr->sa_family == AF_INET) {
                msg.msg_control = &msg_control;
                msg.msg_controllen = sizeof(msg_control);
            }
#endif

#if (NGX_HAVE_INET6 && NGX_HAVE_IPV6_RECVPKTINFO)
            if (ls->sockaddr->sa_family == AF_INET6) {
                msg.msg_control = &msg_control6;
                msg.msg_controllen = sizeof(msg_control6);
            }
#endif
        }

#endif

        n = recvmsg(lc->fd, &msg, 0);

        if (n == -1) {
            err = ngx_socket_errno;

            if (err == NGX_EAGAIN) {
                ngx_log_debug0(NGX_LOG_DEBUG_EVENT, ev->log, err,
                               "recvmsg() not ready");
                return;
            }

            ngx_log_error(NGX_LOG_ALERT, ev->log, err, "recvmsg() failed");

            return;
        }

#if (NGX_HAVE_MSGHDR_MSG_CONTROL)
        if (msg.msg_flags & (MSG_TRUNC|MSG_CTRUNC)) {
            ngx_log_error(NGX_LOG_ALERT, ev->log, 0,
                          "recvmsg() truncated data");
            continue;
        }
#endif

        sockaddr = msg.msg_name;
        socklen = msg.msg_namelen;

        if (socklen > (socklen_t) sizeof(ngx_sockaddr_t)) {
            socklen = sizeof(ngx_sockaddr_t);
        }

        if (socklen == 0) {

            /*
             * on Linux recvmsg() returns zero msg_namelen
             * when receiving packets from unbound AF_UNIX sockets
             */

            socklen = sizeof(struct sockaddr);
            ngx_memzero(&sa, sizeof(struct sockaddr));
            sa.sockaddr.sa_family = ls->sockaddr->sa_family;
        }

        local_sockaddr = ls->sockaddr;
        local_socklen = ls->socklen;

#if (NGX_HAVE_MSGHDR_MSG_CONTROL)

        if (ls->wildcard) {
            struct cmsghdr  *cmsg;

            ngx_memcpy(&lsa, local_sockaddr, local_socklen);
            local_sockaddr = &lsa.sockaddr;

            for (cmsg = CMSG_FIRSTHDR(&msg);
                 cmsg != NULL;
                 cmsg = CMSG_NXTHDR(&msg, cmsg))
            {

#if (NGX_HAVE_IP_RECVDSTADDR)

                if (cmsg->cmsg_level == IPPROTO_IP
                    && cmsg->cmsg_type == IP_RECVDSTADDR
                    && local_sockaddr->sa_family == AF_INET)
                {
                    struct in_addr      *addr;
                    struct sockaddr_in  *sin;

                    addr = (struct in_addr *) CMSG_DATA(cmsg);
                    sin = (struct sockaddr_in *) local_sockaddr;
                    sin->sin_addr = *addr;

                    break;
                }

#elif (NGX_HAVE_IP_PKTINFO)

                if (cmsg->cmsg_level == IPPROTO_IP
                    && cmsg->cmsg_type == IP_PKTINFO
                    && local_sockaddr->sa_family == AF_INET)
                {
                    struct in_pktinfo   *pkt;
                    struct sockaddr_in  *sin;

                    pkt = (struct in_pktinfo *) CMSG_DATA(cmsg);
                    sin = (struct sockaddr_in *) local_sockaddr;
                    sin->sin_addr = pkt->ipi_addr;

                    break;
                }

#endif

#if (NGX_HAVE_INET6 && NGX_HAVE_IPV6_RECVPKTINFO)

                if (cmsg->cmsg_level == IPPROTO_IPV6
                    && cmsg->cmsg_type == IPV6_PKTINFO
                    && local_sockaddr->sa_family == AF_INET6)
                {
                    struct in6_pktinfo   *pkt6;
                    struct sockaddr_in6  *sin6;

                    pkt6 = (struct in6_pktinfo *) CMSG_DATA(cmsg);
                    sin6 = (struct sockaddr_in6 *) local_sockaddr;
                    sin6->sin6_addr = pkt6->ipi6_addr;

                    break;
                }

#endif

            }
        }

#endif

        c = ngx_lookup_udp_connection(ls, sockaddr, socklen, local_sockaddr,
                                      local_socklen);

        if (c) {

#if (NGX_DEBUG)
            if (c->log->log_level & NGX_LOG_DEBUG_EVENT) {
                ngx_log_handler_pt  handler;

                handler = c->log->handler;
                c->log->handler = NULL;

                ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
                               "recvmsg: fd:%d n:%z", c->fd, n);

                c->log->handler = handler;
            }
#endif

            ngx_memzero(&buf, sizeof(ngx_buf_t));

            buf.pos = buffer;
            buf.last = buffer + n;

            rev = c->read;

            c->udp->buffer = &buf;
            rev->ready = 1;

            rev->handler(rev);

            c->udp->buffer = NULL;
            rev->ready = 0;

            goto next;
        }

#if (NGX_STAT_STUB)
        (void) ngx_atomic_fetch_add(ngx_stat_accepted, 1);
#endif

        ngx_accept_disabled = ngx_cycle->connection_n / 8
                              - ngx_cycle->free_connection_n;

        c = ngx_get_connection(lc->fd, ev->log);
        if (c == NULL) {
            return;
        }

        c->shared = 1;
        c->type = SOCK_DGRAM;
        c->socklen = socklen;

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

        c->pool = ngx_create_pool(ls->pool_size, ev->log);
        if (c->pool == NULL) {
            ngx_close_accepted_udp_connection(c);
            return;
        }

        c->sockaddr = ngx_palloc(c->pool, socklen);
        if (c->sockaddr == NULL) {
            ngx_close_accepted_udp_connection(c);
            return;
        }

        ngx_memcpy(c->sockaddr, sockaddr, socklen);

        log = ngx_palloc(c->pool, sizeof(ngx_log_t));
        if (log == NULL) {
            ngx_close_accepted_udp_connection(c);
            return;
        }

        *log = ls->log;

        c->recv = ngx_udp_shared_recv;
        c->send = ngx_udp_send;
        c->send_chain = ngx_udp_send_chain;

        c->log = log;
        c->pool->log = log;
        c->listening = ls;

        if (local_sockaddr == &lsa.sockaddr) {
            local_sockaddr = ngx_palloc(c->pool, local_socklen);
            if (local_sockaddr == NULL) {
                ngx_close_accepted_udp_connection(c);
                return;
            }

            ngx_memcpy(local_sockaddr, &lsa, local_socklen);
        }

        c->local_sockaddr = local_sockaddr;
        c->local_socklen = local_socklen;

        c->buffer = ngx_create_temp_buf(c->pool, n);
        if (c->buffer == NULL) {
            ngx_close_accepted_udp_connection(c);
            return;
        }

        c->buffer->last = ngx_cpymem(c->buffer->last, buffer, n);

        rev = c->read;
        wev = c->write;

        wev->ready = 1;

        rev->log = log;
        wev->log = log;

        /*
         * TODO: MT: - ngx_atomic_fetch_add()
         *             or protection by critical section or light mutex
         *
         * TODO: MP: - allocated in a shared memory
         *           - ngx_atomic_fetch_add()
         *             or protection by critical section or light mutex
         */

        c->number = ngx_atomic_fetch_add(ngx_connection_counter, 1);

#if (NGX_STAT_STUB)
        (void) ngx_atomic_fetch_add(ngx_stat_handled, 1);
#endif

        if (ls->addr_ntop) {
            c->addr_text.data = ngx_pnalloc(c->pool, ls->addr_text_max_len);
            if (c->addr_text.data == NULL) {
                ngx_close_accepted_udp_connection(c);
                return;
            }

            c->addr_text.len = ngx_sock_ntop(c->sockaddr, c->socklen,
                                             c->addr_text.data,
                                             ls->addr_text_max_len, 0);
            if (c->addr_text.len == 0) {
                ngx_close_accepted_udp_connection(c);
                return;
            }
        }

#if (NGX_DEBUG)
        {
        ngx_str_t  addr;
        u_char     text[NGX_SOCKADDR_STRLEN];

        ngx_debug_accepted_connection(ecf, c);

        if (log->log_level & NGX_LOG_DEBUG_EVENT) {
            addr.data = text;
            addr.len = ngx_sock_ntop(c->sockaddr, c->socklen, text,
                                     NGX_SOCKADDR_STRLEN, 1);

            ngx_log_debug4(NGX_LOG_DEBUG_EVENT, log, 0,
                           "*%uA recvmsg: %V fd:%d n:%z",
                           c->number, &addr, c->fd, n);
        }

        }
#endif

        if (ngx_insert_udp_connection(c) != NGX_OK) {
            ngx_close_accepted_udp_connection(c);
            return;
        }

        log->data = NULL;
        log->handler = NULL;

        ls->handler(c);

    next:

        if (ngx_event_flags & NGX_USE_KQUEUE_EVENT) {
            ev->available -= n;
        }

    } while (ev->available);
}


static void
ngx_close_accepted_udp_connection(ngx_connection_t *c)
{
    ngx_free_connection(c);

    c->fd = (ngx_socket_t) -1;

    if (c->pool) {
        ngx_destroy_pool(c->pool);
    }

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


static ssize_t
ngx_udp_shared_recv(ngx_connection_t *c, u_char *buf, size_t size)
{
    ssize_t     n;
    ngx_buf_t  *b;

    if (c->udp == NULL || c->udp->buffer == NULL) {
        return NGX_AGAIN;
    }

    b = c->udp->buffer;

    n = ngx_min(b->last - b->pos, (ssize_t) size);

    ngx_memcpy(buf, b->pos, n);

    c->udp->buffer = NULL;
    c->read->ready = 0;

    return n;
}


void
ngx_udp_rbtree_insert_value(ngx_rbtree_node_t *temp,
    ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel)
{
    ngx_int_t               rc;
    ngx_connection_t       *c, *ct;
    ngx_rbtree_node_t     **p;
    ngx_udp_connection_t   *udp, *udpt;

    for ( ;; ) {

        if (node->key < temp->key) {

            p = &temp->left;

        } else if (node->key > temp->key) {

            p = &temp->right;

        } else { /* node->key == temp->key */

            udp = (ngx_udp_connection_t *) node;
            c = udp->connection;

            udpt = (ngx_udp_connection_t *) temp;
            ct = udpt->connection;

            rc = ngx_cmp_sockaddr(c->sockaddr, c->socklen,
                                  ct->sockaddr, ct->socklen, 1);

            if (rc == 0 && c->listening->wildcard) {
                rc = ngx_cmp_sockaddr(c->local_sockaddr, c->local_socklen,
                                      ct->local_sockaddr, ct->local_socklen, 1);
            }

            p = (rc < 0) ? &temp->left : &temp->right;
        }

        if (*p == sentinel) {
            break;
        }

        temp = *p;
    }

    *p = node;
    node->parent = temp;
    node->left = sentinel;
    node->right = sentinel;
    ngx_rbt_red(node);
}


static ngx_int_t
ngx_insert_udp_connection(ngx_connection_t *c)
{
    uint32_t               hash;
    ngx_pool_cleanup_t    *cln;
    ngx_udp_connection_t  *udp;

    if (c->udp) {
        return NGX_OK;
    }

    udp = ngx_pcalloc(c->pool, sizeof(ngx_udp_connection_t));
    if (udp == NULL) {
        return NGX_ERROR;
    }

    udp->connection = c;

    ngx_crc32_init(hash);
    ngx_crc32_update(&hash, (u_char *) c->sockaddr, c->socklen);

    if (c->listening->wildcard) {
        ngx_crc32_update(&hash, (u_char *) c->local_sockaddr, c->local_socklen);
    }

    ngx_crc32_final(hash);

    udp->node.key = hash;

    cln = ngx_pool_cleanup_add(c->pool, 0);
    if (cln == NULL) {
        return NGX_ERROR;
    }

    cln->data = c;
    cln->handler = ngx_delete_udp_connection;

    ngx_rbtree_insert(&c->listening->rbtree, &udp->node);

    c->udp = udp;

    return NGX_OK;
}


static void
ngx_delete_udp_connection(void *data)
{
    ngx_connection_t  *c = data;

    ngx_rbtree_delete(&c->listening->rbtree, &c->udp->node);
}


static ngx_connection_t *
ngx_lookup_udp_connection(ngx_listening_t *ls, struct sockaddr *sockaddr,
    socklen_t socklen, struct sockaddr *local_sockaddr, socklen_t local_socklen)
{
    uint32_t               hash;
    ngx_int_t              rc;
    ngx_connection_t      *c;
    ngx_rbtree_node_t     *node, *sentinel;
    ngx_udp_connection_t  *udp;

#if (NGX_HAVE_UNIX_DOMAIN)

    if (sockaddr->sa_family == AF_UNIX) {
        struct sockaddr_un *saun = (struct sockaddr_un *) sockaddr;

        if (socklen <= (socklen_t) offsetof(struct sockaddr_un, sun_path)
            || saun->sun_path[0] == '\0')
        {
            ngx_log_debug0(NGX_LOG_DEBUG_EVENT, ngx_cycle->log, 0,
                           "unbound unix socket");
            return NULL;
        }
    }

#endif

    node = ls->rbtree.root;
    sentinel = ls->rbtree.sentinel;

    ngx_crc32_init(hash);
    ngx_crc32_update(&hash, (u_char *) sockaddr, socklen);

    if (ls->wildcard) {
        ngx_crc32_update(&hash, (u_char *) local_sockaddr, local_socklen);
    }

    ngx_crc32_final(hash);

    while (node != sentinel) {

        if (hash < node->key) {
            node = node->left;
            continue;
        }

        if (hash > node->key) {
            node = node->right;
            continue;
        }

        /* hash == node->key */

        udp = (ngx_udp_connection_t *) node;

        c = udp->connection;

        rc = ngx_cmp_sockaddr(sockaddr, socklen,
                              c->sockaddr, c->socklen, 1);

        if (rc == 0 && ls->wildcard) {
            rc = ngx_cmp_sockaddr(local_sockaddr, local_socklen,
                                  c->local_sockaddr, c->local_socklen, 1);
        }

        if (rc == 0) {
            return c;
        }

        node = (rc < 0) ? node->left : node->right;
    }

    return NULL;
}

#endif