view src/stream/ngx_stream_upstream.c @ 7680:39501ce97e29

gRPC: generate error when response size is wrong. As long as the "Content-Length" header is given, we now make sure it exactly matches the size of the response. If it doesn't, the response is considered malformed and must not be forwarded (https://tools.ietf.org/html/rfc7540#section-8.1.2.6). While it is not really possible to "not forward" the response which is already being forwarded, we generate an error instead, which is the closest equivalent. Previous behaviour was to pass everything to the client, but this seems to be suboptimal and causes issues (ticket #1695). Also this directly contradicts HTTP/2 specification requirements. Note that the new behaviour for the gRPC proxy is more strict than that applied in other variants of proxying. This is intentional, as HTTP/2 specification requires us to do so, while in other types of proxying malformed responses from backends are well known and historically tolerated.
author Maxim Dounin <mdounin@mdounin.ru>
date Mon, 06 Jul 2020 18:36:25 +0300
parents 860d3907da1c
children
line wrap: on
line source


/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


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


static ngx_int_t ngx_stream_upstream_add_variables(ngx_conf_t *cf);
static ngx_int_t ngx_stream_upstream_addr_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data);
static ngx_int_t ngx_stream_upstream_response_time_variable(
    ngx_stream_session_t *s, ngx_stream_variable_value_t *v, uintptr_t data);
static ngx_int_t ngx_stream_upstream_bytes_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data);

static char *ngx_stream_upstream(ngx_conf_t *cf, ngx_command_t *cmd,
    void *dummy);
static char *ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static void *ngx_stream_upstream_create_main_conf(ngx_conf_t *cf);
static char *ngx_stream_upstream_init_main_conf(ngx_conf_t *cf, void *conf);


static ngx_command_t  ngx_stream_upstream_commands[] = {

    { ngx_string("upstream"),
      NGX_STREAM_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_TAKE1,
      ngx_stream_upstream,
      0,
      0,
      NULL },

    { ngx_string("server"),
      NGX_STREAM_UPS_CONF|NGX_CONF_1MORE,
      ngx_stream_upstream_server,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

      ngx_null_command
};


static ngx_stream_module_t  ngx_stream_upstream_module_ctx = {
    ngx_stream_upstream_add_variables,     /* preconfiguration */
    NULL,                                  /* postconfiguration */

    ngx_stream_upstream_create_main_conf,  /* create main configuration */
    ngx_stream_upstream_init_main_conf,    /* init main configuration */

    NULL,                                  /* create server configuration */
    NULL                                   /* merge server configuration */
};


ngx_module_t  ngx_stream_upstream_module = {
    NGX_MODULE_V1,
    &ngx_stream_upstream_module_ctx,       /* module context */
    ngx_stream_upstream_commands,          /* module directives */
    NGX_STREAM_MODULE,                     /* module type */
    NULL,                                  /* init master */
    NULL,                                  /* init module */
    NULL,                                  /* init process */
    NULL,                                  /* init thread */
    NULL,                                  /* exit thread */
    NULL,                                  /* exit process */
    NULL,                                  /* exit master */
    NGX_MODULE_V1_PADDING
};


static ngx_stream_variable_t  ngx_stream_upstream_vars[] = {

    { ngx_string("upstream_addr"), NULL,
      ngx_stream_upstream_addr_variable, 0,
      NGX_STREAM_VAR_NOCACHEABLE, 0 },

    { ngx_string("upstream_bytes_sent"), NULL,
      ngx_stream_upstream_bytes_variable, 0,
      NGX_STREAM_VAR_NOCACHEABLE, 0 },

    { ngx_string("upstream_connect_time"), NULL,
      ngx_stream_upstream_response_time_variable, 2,
      NGX_STREAM_VAR_NOCACHEABLE, 0 },

    { ngx_string("upstream_first_byte_time"), NULL,
      ngx_stream_upstream_response_time_variable, 1,
      NGX_STREAM_VAR_NOCACHEABLE, 0 },

    { ngx_string("upstream_session_time"), NULL,
      ngx_stream_upstream_response_time_variable, 0,
      NGX_STREAM_VAR_NOCACHEABLE, 0 },

    { ngx_string("upstream_bytes_received"), NULL,
      ngx_stream_upstream_bytes_variable, 1,
      NGX_STREAM_VAR_NOCACHEABLE, 0 },

      ngx_stream_null_variable
};


static ngx_int_t
ngx_stream_upstream_add_variables(ngx_conf_t *cf)
{
    ngx_stream_variable_t  *var, *v;

    for (v = ngx_stream_upstream_vars; v->name.len; v++) {
        var = ngx_stream_add_variable(cf, &v->name, v->flags);
        if (var == NULL) {
            return NGX_ERROR;
        }

        var->get_handler = v->get_handler;
        var->data = v->data;
    }

    return NGX_OK;
}


static ngx_int_t
ngx_stream_upstream_addr_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data)
{
    u_char                       *p;
    size_t                        len;
    ngx_uint_t                    i;
    ngx_stream_upstream_state_t  *state;

    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;

    if (s->upstream_states == NULL || s->upstream_states->nelts == 0) {
        v->not_found = 1;
        return NGX_OK;
    }

    len = 0;
    state = s->upstream_states->elts;

    for (i = 0; i < s->upstream_states->nelts; i++) {
        if (state[i].peer) {
            len += state[i].peer->len;
        }

        len += 2;
    }

    p = ngx_pnalloc(s->connection->pool, len);
    if (p == NULL) {
        return NGX_ERROR;
    }

    v->data = p;

    i = 0;

    for ( ;; ) {
        if (state[i].peer) {
            p = ngx_cpymem(p, state[i].peer->data, state[i].peer->len);
        }

        if (++i == s->upstream_states->nelts) {
            break;
        }

        *p++ = ',';
        *p++ = ' ';
    }

    v->len = p - v->data;

    return NGX_OK;
}


static ngx_int_t
ngx_stream_upstream_bytes_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data)
{
    u_char                       *p;
    size_t                        len;
    ngx_uint_t                    i;
    ngx_stream_upstream_state_t  *state;

    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;

    if (s->upstream_states == NULL || s->upstream_states->nelts == 0) {
        v->not_found = 1;
        return NGX_OK;
    }

    len = s->upstream_states->nelts * (NGX_OFF_T_LEN + 2);

    p = ngx_pnalloc(s->connection->pool, len);
    if (p == NULL) {
        return NGX_ERROR;
    }

    v->data = p;

    i = 0;
    state = s->upstream_states->elts;

    for ( ;; ) {

        if (data == 1) {
            p = ngx_sprintf(p, "%O", state[i].bytes_received);

        } else {
            p = ngx_sprintf(p, "%O", state[i].bytes_sent);
        }

        if (++i == s->upstream_states->nelts) {
            break;
        }

        *p++ = ',';
        *p++ = ' ';
    }

    v->len = p - v->data;

    return NGX_OK;
}


static ngx_int_t
ngx_stream_upstream_response_time_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data)
{
    u_char                       *p;
    size_t                        len;
    ngx_uint_t                    i;
    ngx_msec_int_t                ms;
    ngx_stream_upstream_state_t  *state;

    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;

    if (s->upstream_states == NULL || s->upstream_states->nelts == 0) {
        v->not_found = 1;
        return NGX_OK;
    }

    len = s->upstream_states->nelts * (NGX_TIME_T_LEN + 4 + 2);

    p = ngx_pnalloc(s->connection->pool, len);
    if (p == NULL) {
        return NGX_ERROR;
    }

    v->data = p;

    i = 0;
    state = s->upstream_states->elts;

    for ( ;; ) {

        if (data == 1) {
            ms = state[i].first_byte_time;

        } else if (data == 2) {
            ms = state[i].connect_time;

        } else {
            ms = state[i].response_time;
        }

        if (ms != -1) {
            ms = ngx_max(ms, 0);
            p = ngx_sprintf(p, "%T.%03M", (time_t) ms / 1000, ms % 1000);

        } else {
            *p++ = '-';
        }

        if (++i == s->upstream_states->nelts) {
            break;
        }

        *p++ = ',';
        *p++ = ' ';
    }

    v->len = p - v->data;

    return NGX_OK;
}


static char *
ngx_stream_upstream(ngx_conf_t *cf, ngx_command_t *cmd, void *dummy)
{
    char                            *rv;
    void                            *mconf;
    ngx_str_t                       *value;
    ngx_url_t                        u;
    ngx_uint_t                       m;
    ngx_conf_t                       pcf;
    ngx_stream_module_t             *module;
    ngx_stream_conf_ctx_t           *ctx, *stream_ctx;
    ngx_stream_upstream_srv_conf_t  *uscf;

    ngx_memzero(&u, sizeof(ngx_url_t));

    value = cf->args->elts;
    u.host = value[1];
    u.no_resolve = 1;
    u.no_port = 1;

    uscf = ngx_stream_upstream_add(cf, &u, NGX_STREAM_UPSTREAM_CREATE
                                           |NGX_STREAM_UPSTREAM_WEIGHT
                                           |NGX_STREAM_UPSTREAM_MAX_CONNS
                                           |NGX_STREAM_UPSTREAM_MAX_FAILS
                                           |NGX_STREAM_UPSTREAM_FAIL_TIMEOUT
                                           |NGX_STREAM_UPSTREAM_DOWN
                                           |NGX_STREAM_UPSTREAM_BACKUP);
    if (uscf == NULL) {
        return NGX_CONF_ERROR;
    }


    ctx = ngx_pcalloc(cf->pool, sizeof(ngx_stream_conf_ctx_t));
    if (ctx == NULL) {
        return NGX_CONF_ERROR;
    }

    stream_ctx = cf->ctx;
    ctx->main_conf = stream_ctx->main_conf;

    /* the upstream{}'s srv_conf */

    ctx->srv_conf = ngx_pcalloc(cf->pool,
                                sizeof(void *) * ngx_stream_max_module);
    if (ctx->srv_conf == NULL) {
        return NGX_CONF_ERROR;
    }

    ctx->srv_conf[ngx_stream_upstream_module.ctx_index] = uscf;

    uscf->srv_conf = ctx->srv_conf;

    for (m = 0; cf->cycle->modules[m]; m++) {
        if (cf->cycle->modules[m]->type != NGX_STREAM_MODULE) {
            continue;
        }

        module = cf->cycle->modules[m]->ctx;

        if (module->create_srv_conf) {
            mconf = module->create_srv_conf(cf);
            if (mconf == NULL) {
                return NGX_CONF_ERROR;
            }

            ctx->srv_conf[cf->cycle->modules[m]->ctx_index] = mconf;
        }
    }

    uscf->servers = ngx_array_create(cf->pool, 4,
                                     sizeof(ngx_stream_upstream_server_t));
    if (uscf->servers == NULL) {
        return NGX_CONF_ERROR;
    }


    /* parse inside upstream{} */

    pcf = *cf;
    cf->ctx = ctx;
    cf->cmd_type = NGX_STREAM_UPS_CONF;

    rv = ngx_conf_parse(cf, NULL);

    *cf = pcf;

    if (rv != NGX_CONF_OK) {
        return rv;
    }

    if (uscf->servers->nelts == 0) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "no servers are inside upstream");
        return NGX_CONF_ERROR;
    }

    return rv;
}


static char *
ngx_stream_upstream_server(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_upstream_srv_conf_t  *uscf = conf;

    time_t                         fail_timeout;
    ngx_str_t                     *value, s;
    ngx_url_t                      u;
    ngx_int_t                      weight, max_conns, max_fails;
    ngx_uint_t                     i;
    ngx_stream_upstream_server_t  *us;

    us = ngx_array_push(uscf->servers);
    if (us == NULL) {
        return NGX_CONF_ERROR;
    }

    ngx_memzero(us, sizeof(ngx_stream_upstream_server_t));

    value = cf->args->elts;

    weight = 1;
    max_conns = 0;
    max_fails = 1;
    fail_timeout = 10;

    for (i = 2; i < cf->args->nelts; i++) {

        if (ngx_strncmp(value[i].data, "weight=", 7) == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_WEIGHT)) {
                goto not_supported;
            }

            weight = ngx_atoi(&value[i].data[7], value[i].len - 7);

            if (weight == NGX_ERROR || weight == 0) {
                goto invalid;
            }

            continue;
        }

        if (ngx_strncmp(value[i].data, "max_conns=", 10) == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_MAX_CONNS)) {
                goto not_supported;
            }

            max_conns = ngx_atoi(&value[i].data[10], value[i].len - 10);

            if (max_conns == NGX_ERROR) {
                goto invalid;
            }

            continue;
        }

        if (ngx_strncmp(value[i].data, "max_fails=", 10) == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_MAX_FAILS)) {
                goto not_supported;
            }

            max_fails = ngx_atoi(&value[i].data[10], value[i].len - 10);

            if (max_fails == NGX_ERROR) {
                goto invalid;
            }

            continue;
        }

        if (ngx_strncmp(value[i].data, "fail_timeout=", 13) == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_FAIL_TIMEOUT)) {
                goto not_supported;
            }

            s.len = value[i].len - 13;
            s.data = &value[i].data[13];

            fail_timeout = ngx_parse_time(&s, 1);

            if (fail_timeout == (time_t) NGX_ERROR) {
                goto invalid;
            }

            continue;
        }

        if (ngx_strcmp(value[i].data, "backup") == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_BACKUP)) {
                goto not_supported;
            }

            us->backup = 1;

            continue;
        }

        if (ngx_strcmp(value[i].data, "down") == 0) {

            if (!(uscf->flags & NGX_STREAM_UPSTREAM_DOWN)) {
                goto not_supported;
            }

            us->down = 1;

            continue;
        }

        goto invalid;
    }

    ngx_memzero(&u, sizeof(ngx_url_t));

    u.url = value[1];

    if (ngx_parse_url(cf->pool, &u) != NGX_OK) {
        if (u.err) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "%s in upstream \"%V\"", u.err, &u.url);
        }

        return NGX_CONF_ERROR;
    }

    if (u.no_port) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "no port in upstream \"%V\"", &u.url);
        return NGX_CONF_ERROR;
    }

    us->name = u.url;
    us->addrs = u.addrs;
    us->naddrs = u.naddrs;
    us->weight = weight;
    us->max_conns = max_conns;
    us->max_fails = max_fails;
    us->fail_timeout = fail_timeout;

    return NGX_CONF_OK;

invalid:

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                       "invalid parameter \"%V\"", &value[i]);

    return NGX_CONF_ERROR;

not_supported:

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                       "balancing method does not support parameter \"%V\"",
                       &value[i]);

    return NGX_CONF_ERROR;
}


ngx_stream_upstream_srv_conf_t *
ngx_stream_upstream_add(ngx_conf_t *cf, ngx_url_t *u, ngx_uint_t flags)
{
    ngx_uint_t                        i;
    ngx_stream_upstream_server_t     *us;
    ngx_stream_upstream_srv_conf_t   *uscf, **uscfp;
    ngx_stream_upstream_main_conf_t  *umcf;

    if (!(flags & NGX_STREAM_UPSTREAM_CREATE)) {

        if (ngx_parse_url(cf->pool, u) != NGX_OK) {
            if (u->err) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                   "%s in upstream \"%V\"", u->err, &u->url);
            }

            return NULL;
        }
    }

    umcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_upstream_module);

    uscfp = umcf->upstreams.elts;

    for (i = 0; i < umcf->upstreams.nelts; i++) {

        if (uscfp[i]->host.len != u->host.len
            || ngx_strncasecmp(uscfp[i]->host.data, u->host.data, u->host.len)
               != 0)
        {
            continue;
        }

        if ((flags & NGX_STREAM_UPSTREAM_CREATE)
             && (uscfp[i]->flags & NGX_STREAM_UPSTREAM_CREATE))
        {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "duplicate upstream \"%V\"", &u->host);
            return NULL;
        }

        if ((uscfp[i]->flags & NGX_STREAM_UPSTREAM_CREATE) && !u->no_port) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "upstream \"%V\" may not have port %d",
                               &u->host, u->port);
            return NULL;
        }

        if ((flags & NGX_STREAM_UPSTREAM_CREATE) && !uscfp[i]->no_port) {
            ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                          "upstream \"%V\" may not have port %d in %s:%ui",
                          &u->host, uscfp[i]->port,
                          uscfp[i]->file_name, uscfp[i]->line);
            return NULL;
        }

        if (uscfp[i]->port != u->port) {
            continue;
        }

        if (flags & NGX_STREAM_UPSTREAM_CREATE) {
            uscfp[i]->flags = flags;
        }

        return uscfp[i];
    }

    uscf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_upstream_srv_conf_t));
    if (uscf == NULL) {
        return NULL;
    }

    uscf->flags = flags;
    uscf->host = u->host;
    uscf->file_name = cf->conf_file->file.name.data;
    uscf->line = cf->conf_file->line;
    uscf->port = u->port;
    uscf->no_port = u->no_port;

    if (u->naddrs == 1 && (u->port || u->family == AF_UNIX)) {
        uscf->servers = ngx_array_create(cf->pool, 1,
                                         sizeof(ngx_stream_upstream_server_t));
        if (uscf->servers == NULL) {
            return NULL;
        }

        us = ngx_array_push(uscf->servers);
        if (us == NULL) {
            return NULL;
        }

        ngx_memzero(us, sizeof(ngx_stream_upstream_server_t));

        us->addrs = u->addrs;
        us->naddrs = 1;
    }

    uscfp = ngx_array_push(&umcf->upstreams);
    if (uscfp == NULL) {
        return NULL;
    }

    *uscfp = uscf;

    return uscf;
}


static void *
ngx_stream_upstream_create_main_conf(ngx_conf_t *cf)
{
    ngx_stream_upstream_main_conf_t  *umcf;

    umcf = ngx_pcalloc(cf->pool, sizeof(ngx_stream_upstream_main_conf_t));
    if (umcf == NULL) {
        return NULL;
    }

    if (ngx_array_init(&umcf->upstreams, cf->pool, 4,
                       sizeof(ngx_stream_upstream_srv_conf_t *))
        != NGX_OK)
    {
        return NULL;
    }

    return umcf;
}


static char *
ngx_stream_upstream_init_main_conf(ngx_conf_t *cf, void *conf)
{
    ngx_stream_upstream_main_conf_t *umcf = conf;

    ngx_uint_t                        i;
    ngx_stream_upstream_init_pt       init;
    ngx_stream_upstream_srv_conf_t  **uscfp;

    uscfp = umcf->upstreams.elts;

    for (i = 0; i < umcf->upstreams.nelts; i++) {

        init = uscfp[i]->peer.init_upstream
                                         ? uscfp[i]->peer.init_upstream
                                         : ngx_stream_upstream_init_round_robin;

        if (init(cf, uscfp[i]) != NGX_OK) {
            return NGX_CONF_ERROR;
        }
    }

    return NGX_CONF_OK;
}