view src/event/ngx_event_udp.c @ 8144:6bee5e692579

SSL: logging levels of various errors reported with tlsfuzzer. To further differentiate client-related errors and adjust logging levels of various SSL errors, nginx was tested with tlsfuzzer with multiple OpenSSL versions (3.1.0-beta1, 3.0.8, 1.1.1t, 1.1.0l, 1.0.2u, 1.0.1u, 1.0.0s, 0.9.8zh). The following errors were observed during tlsfuzzer runs with OpenSSL 3.0.8, and are clearly client-related: SSL_do_handshake() failed (SSL: error:0A000092:SSL routines::data length too long) SSL_do_handshake() failed (SSL: error:0A0000A0:SSL routines::length too short) SSL_do_handshake() failed (SSL: error:0A000124:SSL routines::bad legacy version) SSL_do_handshake() failed (SSL: error:0A000178:SSL routines::no shared signature algorithms) Accordingly, the SSL_R_DATA_LENGTH_TOO_LONG ("data length too long"), SSL_R_LENGTH_TOO_SHORT ("length too short"), SSL_R_BAD_LEGACY_VERSION ("bad legacy version"), and SSL_R_NO_SHARED_SIGNATURE_ALGORITHMS ("no shared signature algorithms", misspelled as "sigature" in OpenSSL 1.0.2) errors are now logged at the "info" level. Additionally, the following errors were observed with OpenSSL 3.0.8 and with TLSv1.3 enabled: SSL_do_handshake() failed (SSL: error:0A00006F:SSL routines::bad digest length) SSL_do_handshake() failed (SSL: error:0A000070:SSL routines::missing sigalgs extension) SSL_do_handshake() failed (SSL: error:0A000096:SSL routines::encrypted length too long) SSL_do_handshake() failed (SSL: error:0A00010F:SSL routines::bad length) SSL_read() failed (SSL: error:0A00007A:SSL routines::bad key update) SSL_read() failed (SSL: error:0A000125:SSL routines::mixed handshake and non handshake data) Accordingly, the SSL_R_BAD_DIGEST_LENGTH ("bad digest length"), SSL_R_MISSING_SIGALGS_EXTENSION ("missing sigalgs extension"), SSL_R_ENCRYPTED_LENGTH_TOO_LONG ("encrypted length too long"), SSL_R_BAD_LENGTH ("bad length"), SSL_R_BAD_KEY_UPDATE ("bad key update"), and SSL_R_MIXED_HANDSHAKE_AND_NON_HANDSHAKE_DATA ("mixed handshake and non handshake data") errors are now logged at the "info" level. Additionally, the following errors were observed with OpenSSL 1.1.1t: SSL_do_handshake() failed (SSL: error:14094091:SSL routines:ssl3_read_bytes:data between ccs and finished) SSL_do_handshake() failed (SSL: error:14094199:SSL routines:ssl3_read_bytes:too many warn alerts) SSL_read() failed (SSL: error:1408F0C6:SSL routines:ssl3_get_record:packet length too long) SSL_read() failed (SSL: error:14094085:SSL routines:ssl3_read_bytes:ccs received early) Accordingly, the SSL_R_CCS_RECEIVED_EARLY ("ccs received early"), SSL_R_DATA_BETWEEN_CCS_AND_FINISHED ("data between ccs and finished"), SSL_R_PACKET_LENGTH_TOO_LONG ("packet length too long"), and SSL_R_TOO_MANY_WARN_ALERTS ("too many warn alerts") errors are now logged at the "info" level. Additionally, the following errors were observed with OpenSSL 1.0.2u: SSL_do_handshake() failed (SSL: error:1407612A:SSL routines:SSL23_GET_CLIENT_HELLO:record too small) SSL_do_handshake() failed (SSL: error:1408C09A:SSL routines:ssl3_get_finished:got a fin before a ccs) Accordingly, the SSL_R_RECORD_TOO_SMALL ("record too small") and SSL_R_GOT_A_FIN_BEFORE_A_CCS ("got a fin before a ccs") errors are now logged at the "info" level. No additional client-related errors were observed while testing with OpenSSL 3.1.0-beta1, OpenSSL 1.1.0l, OpenSSL 1.0.1u, OpenSSL 1.0.0s, and OpenSSL 0.9.8zh.
author Maxim Dounin <mdounin@mdounin.ru>
date Wed, 08 Mar 2023 22:21:59 +0300
parents 3108d4d668e4
children af5adec171b4
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 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_ADDRINFO_CMSG)
    u_char             msg_control[CMSG_SPACE(sizeof(ngx_addrinfo_t))];
#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_ADDRINFO_CMSG)
        if (ls->wildcard) {
            msg.msg_control = &msg_control;
            msg.msg_controllen = sizeof(msg_control);

            ngx_memzero(&msg_control, sizeof(msg_control));
        }
#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_ADDRINFO_CMSG)
        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_ADDRINFO_CMSG)

        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_get_srcaddr_cmsg(cmsg, local_sockaddr) == NGX_OK) {
                    break;
                }
            }
        }

#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->active = 0;

            rev->handler(rev);

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

            rev->ready = 0;
            rev->active = 1;

            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->need_flush_buf = 1;

        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;

        rev->active = 1;
        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);

        c->start_time = ngx_current_msec;

#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;
    c->read->active = 1;

    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;
}


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

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

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

    c->udp = NULL;
}


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;
}

#else

void
ngx_delete_udp_connection(void *data)
{
    return;
}

#endif