view src/stream/ngx_stream_map_module.c @ 6694:ea9dfe2f62e7

Stream: preread phase. In this phase, head of a stream is read and analysed before proceeding to the content phase. Amount of data read is controlled by the module implementing the phase, but not more than defined by the "preread_buffer_size" directive. The time spent on processing preread is controlled by the "preread_timeout" directive. The typical preread phase module will parse the beginning of a stream and set variable that may be used by the content phase, for example to make routing decision.
author Vladimir Homutov <vl@nginx.com>
date Thu, 15 Sep 2016 14:56:02 +0300
parents 8ed51b02f655
children 014905eb7b3d
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>


typedef struct {
    ngx_uint_t                    hash_max_size;
    ngx_uint_t                    hash_bucket_size;
} ngx_stream_map_conf_t;


typedef struct {
    ngx_hash_keys_arrays_t        keys;

    ngx_array_t                  *values_hash;
#if (NGX_PCRE)
    ngx_array_t                   regexes;
#endif

    ngx_stream_variable_value_t  *default_value;
    ngx_conf_t                   *cf;
    ngx_uint_t                    hostnames;      /* unsigned  hostnames:1 */
} ngx_stream_map_conf_ctx_t;


typedef struct {
    ngx_stream_map_t              map;
    ngx_stream_complex_value_t    value;
    ngx_stream_variable_value_t  *default_value;
    ngx_uint_t                    hostnames;      /* unsigned  hostnames:1 */
} ngx_stream_map_ctx_t;


static int ngx_libc_cdecl ngx_stream_map_cmp_dns_wildcards(const void *one,
    const void *two);
static void *ngx_stream_map_create_conf(ngx_conf_t *cf);
static char *ngx_stream_map_block(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static char *ngx_stream_map(ngx_conf_t *cf, ngx_command_t *dummy, void *conf);


static ngx_command_t  ngx_stream_map_commands[] = {

    { ngx_string("map"),
      NGX_STREAM_MAIN_CONF|NGX_CONF_BLOCK|NGX_CONF_TAKE2,
      ngx_stream_map_block,
      NGX_STREAM_MAIN_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("map_hash_max_size"),
      NGX_STREAM_MAIN_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_STREAM_MAIN_CONF_OFFSET,
      offsetof(ngx_stream_map_conf_t, hash_max_size),
      NULL },

    { ngx_string("map_hash_bucket_size"),
      NGX_STREAM_MAIN_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_num_slot,
      NGX_STREAM_MAIN_CONF_OFFSET,
      offsetof(ngx_stream_map_conf_t, hash_bucket_size),
      NULL },

      ngx_null_command
};


static ngx_stream_module_t  ngx_stream_map_module_ctx = {
    NULL,                                  /* preconfiguration */
    NULL,                                  /* postconfiguration */

    ngx_stream_map_create_conf,            /* create main configuration */
    NULL,                                  /* init main configuration */

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


ngx_module_t  ngx_stream_map_module = {
    NGX_MODULE_V1,
    &ngx_stream_map_module_ctx,            /* module context */
    ngx_stream_map_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_int_t
ngx_stream_map_variable(ngx_stream_session_t *s, ngx_stream_variable_value_t *v,
    uintptr_t data)
{
    ngx_stream_map_ctx_t  *map = (ngx_stream_map_ctx_t *) data;

    ngx_str_t                     val, str;
    ngx_stream_complex_value_t   *cv;
    ngx_stream_variable_value_t  *value;

    ngx_log_debug0(NGX_LOG_DEBUG_STREAM, s->connection->log, 0,
                   "stream map started");

    if (ngx_stream_complex_value(s, &map->value, &val) != NGX_OK) {
        return NGX_ERROR;
    }

    if (map->hostnames && val.len > 0 && val.data[val.len - 1] == '.') {
        val.len--;
    }

    value = ngx_stream_map_find(s, &map->map, &val);

    if (value == NULL) {
        value = map->default_value;
    }

    if (!value->valid) {
        cv = (ngx_stream_complex_value_t *) value->data;

        if (ngx_stream_complex_value(s, cv, &str) != NGX_OK) {
            return NGX_ERROR;
        }

        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->len = str.len;
        v->data = str.data;

    } else {
        *v = *value;
    }

    ngx_log_debug2(NGX_LOG_DEBUG_STREAM, s->connection->log, 0,
                   "stream map: \"%V\" \"%v\"", &val, v);

    return NGX_OK;
}


static void *
ngx_stream_map_create_conf(ngx_conf_t *cf)
{
    ngx_stream_map_conf_t  *mcf;

    mcf = ngx_palloc(cf->pool, sizeof(ngx_stream_map_conf_t));
    if (mcf == NULL) {
        return NULL;
    }

    mcf->hash_max_size = NGX_CONF_UNSET_UINT;
    mcf->hash_bucket_size = NGX_CONF_UNSET_UINT;

    return mcf;
}


static char *
ngx_stream_map_block(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_map_conf_t  *mcf = conf;

    char                                *rv;
    ngx_str_t                           *value, name;
    ngx_conf_t                           save;
    ngx_pool_t                          *pool;
    ngx_hash_init_t                      hash;
    ngx_stream_map_ctx_t                *map;
    ngx_stream_variable_t               *var;
    ngx_stream_map_conf_ctx_t            ctx;
    ngx_stream_compile_complex_value_t   ccv;

    if (mcf->hash_max_size == NGX_CONF_UNSET_UINT) {
        mcf->hash_max_size = 2048;
    }

    if (mcf->hash_bucket_size == NGX_CONF_UNSET_UINT) {
        mcf->hash_bucket_size = ngx_cacheline_size;

    } else {
        mcf->hash_bucket_size = ngx_align(mcf->hash_bucket_size,
                                          ngx_cacheline_size);
    }

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

    value = cf->args->elts;

    ngx_memzero(&ccv, sizeof(ngx_stream_compile_complex_value_t));

    ccv.cf = cf;
    ccv.value = &value[1];
    ccv.complex_value = &map->value;

    if (ngx_stream_compile_complex_value(&ccv) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    name = value[2];

    if (name.data[0] != '$') {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid variable name \"%V\"", &name);
        return NGX_CONF_ERROR;
    }

    name.len--;
    name.data++;

    var = ngx_stream_add_variable(cf, &name, NGX_STREAM_VAR_CHANGEABLE);
    if (var == NULL) {
        return NGX_CONF_ERROR;
    }

    var->get_handler = ngx_stream_map_variable;
    var->data = (uintptr_t) map;

    pool = ngx_create_pool(NGX_DEFAULT_POOL_SIZE, cf->log);
    if (pool == NULL) {
        return NGX_CONF_ERROR;
    }

    ctx.keys.pool = cf->pool;
    ctx.keys.temp_pool = pool;

    if (ngx_hash_keys_array_init(&ctx.keys, NGX_HASH_LARGE) != NGX_OK) {
        ngx_destroy_pool(pool);
        return NGX_CONF_ERROR;
    }

    ctx.values_hash = ngx_pcalloc(pool, sizeof(ngx_array_t) * ctx.keys.hsize);
    if (ctx.values_hash == NULL) {
        ngx_destroy_pool(pool);
        return NGX_CONF_ERROR;
    }

#if (NGX_PCRE)
    if (ngx_array_init(&ctx.regexes, cf->pool, 2,
                       sizeof(ngx_stream_map_regex_t))
        != NGX_OK)
    {
        ngx_destroy_pool(pool);
        return NGX_CONF_ERROR;
    }
#endif

    ctx.default_value = NULL;
    ctx.cf = &save;
    ctx.hostnames = 0;

    save = *cf;
    cf->pool = pool;
    cf->ctx = &ctx;
    cf->handler = ngx_stream_map;
    cf->handler_conf = conf;

    rv = ngx_conf_parse(cf, NULL);

    *cf = save;

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

    map->default_value = ctx.default_value ? ctx.default_value:
                                             &ngx_stream_variable_null_value;

    map->hostnames = ctx.hostnames;

    hash.key = ngx_hash_key_lc;
    hash.max_size = mcf->hash_max_size;
    hash.bucket_size = mcf->hash_bucket_size;
    hash.name = "map_hash";
    hash.pool = cf->pool;

    if (ctx.keys.keys.nelts) {
        hash.hash = &map->map.hash.hash;
        hash.temp_pool = NULL;

        if (ngx_hash_init(&hash, ctx.keys.keys.elts, ctx.keys.keys.nelts)
            != NGX_OK)
        {
            ngx_destroy_pool(pool);
            return NGX_CONF_ERROR;
        }
    }

    if (ctx.keys.dns_wc_head.nelts) {

        ngx_qsort(ctx.keys.dns_wc_head.elts,
                  (size_t) ctx.keys.dns_wc_head.nelts,
                  sizeof(ngx_hash_key_t), ngx_stream_map_cmp_dns_wildcards);

        hash.hash = NULL;
        hash.temp_pool = pool;

        if (ngx_hash_wildcard_init(&hash, ctx.keys.dns_wc_head.elts,
                                   ctx.keys.dns_wc_head.nelts)
            != NGX_OK)
        {
            ngx_destroy_pool(pool);
            return NGX_CONF_ERROR;
        }

        map->map.hash.wc_head = (ngx_hash_wildcard_t *) hash.hash;
    }

    if (ctx.keys.dns_wc_tail.nelts) {

        ngx_qsort(ctx.keys.dns_wc_tail.elts,
                  (size_t) ctx.keys.dns_wc_tail.nelts,
                  sizeof(ngx_hash_key_t), ngx_stream_map_cmp_dns_wildcards);

        hash.hash = NULL;
        hash.temp_pool = pool;

        if (ngx_hash_wildcard_init(&hash, ctx.keys.dns_wc_tail.elts,
                                   ctx.keys.dns_wc_tail.nelts)
            != NGX_OK)
        {
            ngx_destroy_pool(pool);
            return NGX_CONF_ERROR;
        }

        map->map.hash.wc_tail = (ngx_hash_wildcard_t *) hash.hash;
    }

#if (NGX_PCRE)

    if (ctx.regexes.nelts) {
        map->map.regex = ctx.regexes.elts;
        map->map.nregex = ctx.regexes.nelts;
    }

#endif

    ngx_destroy_pool(pool);

    return rv;
}


static int ngx_libc_cdecl
ngx_stream_map_cmp_dns_wildcards(const void *one, const void *two)
{
    ngx_hash_key_t  *first, *second;

    first = (ngx_hash_key_t *) one;
    second = (ngx_hash_key_t *) two;

    return ngx_dns_strcmp(first->key.data, second->key.data);
}


static char *
ngx_stream_map(ngx_conf_t *cf, ngx_command_t *dummy, void *conf)
{
    u_char                              *data;
    size_t                               len;
    ngx_int_t                            rv;
    ngx_str_t                           *value, v;
    ngx_uint_t                           i, key;
    ngx_stream_map_conf_ctx_t           *ctx;
    ngx_stream_complex_value_t           cv, *cvp;
    ngx_stream_variable_value_t         *var, **vp;
    ngx_stream_compile_complex_value_t   ccv;

    ctx = cf->ctx;

    value = cf->args->elts;

    if (cf->args->nelts == 1
        && ngx_strcmp(value[0].data, "hostnames") == 0)
    {
        ctx->hostnames = 1;
        return NGX_CONF_OK;

    } else if (cf->args->nelts != 2) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid number of the map parameters");
        return NGX_CONF_ERROR;
    }

    if (ngx_strcmp(value[0].data, "include") == 0) {
        return ngx_conf_include(cf, dummy, conf);
    }

    key = 0;

    for (i = 0; i < value[1].len; i++) {
        key = ngx_hash(key, value[1].data[i]);
    }

    key %= ctx->keys.hsize;

    vp = ctx->values_hash[key].elts;

    if (vp) {
        for (i = 0; i < ctx->values_hash[key].nelts; i++) {

            if (vp[i]->valid) {
                data = vp[i]->data;
                len = vp[i]->len;

            } else {
                cvp = (ngx_stream_complex_value_t *) vp[i]->data;
                data = cvp->value.data;
                len = cvp->value.len;
            }

            if (value[1].len != len) {
                continue;
            }

            if (ngx_strncmp(value[1].data, data, len) == 0) {
                var = vp[i];
                goto found;
            }
        }

    } else {
        if (ngx_array_init(&ctx->values_hash[key], cf->pool, 4,
                           sizeof(ngx_stream_variable_value_t *))
            != NGX_OK)
        {
            return NGX_CONF_ERROR;
        }
    }

    var = ngx_palloc(ctx->keys.pool, sizeof(ngx_stream_variable_value_t));
    if (var == NULL) {
        return NGX_CONF_ERROR;
    }

    v.len = value[1].len;
    v.data = ngx_pstrdup(ctx->keys.pool, &value[1]);
    if (v.data == NULL) {
        return NGX_CONF_ERROR;
    }

    ngx_memzero(&ccv, sizeof(ngx_stream_compile_complex_value_t));

    ccv.cf = ctx->cf;
    ccv.value = &v;
    ccv.complex_value = &cv;

    if (ngx_stream_compile_complex_value(&ccv) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    if (cv.lengths != NULL) {
        cvp = ngx_palloc(ctx->keys.pool, sizeof(ngx_stream_complex_value_t));
        if (cvp == NULL) {
            return NGX_CONF_ERROR;
        }

        *cvp = cv;

        var->len = 0;
        var->data = (u_char *) cvp;
        var->valid = 0;

    } else {
        var->len = v.len;
        var->data = v.data;
        var->valid = 1;
    }

    var->no_cacheable = 0;
    var->not_found = 0;

    vp = ngx_array_push(&ctx->values_hash[key]);
    if (vp == NULL) {
        return NGX_CONF_ERROR;
    }

    *vp = var;

found:

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

        if (ctx->default_value) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "duplicate default map parameter");
            return NGX_CONF_ERROR;
        }

        ctx->default_value = var;

        return NGX_CONF_OK;
    }

#if (NGX_PCRE)

    if (value[0].len && value[0].data[0] == '~') {
        ngx_regex_compile_t      rc;
        ngx_stream_map_regex_t  *regex;
        u_char                   errstr[NGX_MAX_CONF_ERRSTR];

        regex = ngx_array_push(&ctx->regexes);
        if (regex == NULL) {
            return NGX_CONF_ERROR;
        }

        value[0].len--;
        value[0].data++;

        ngx_memzero(&rc, sizeof(ngx_regex_compile_t));

        if (value[0].data[0] == '*') {
            value[0].len--;
            value[0].data++;
            rc.options = NGX_REGEX_CASELESS;
        }

        rc.pattern = value[0];
        rc.err.len = NGX_MAX_CONF_ERRSTR;
        rc.err.data = errstr;

        regex->regex = ngx_stream_regex_compile(ctx->cf, &rc);
        if (regex->regex == NULL) {
            return NGX_CONF_ERROR;
        }

        regex->value = var;

        return NGX_CONF_OK;
    }

#endif

    if (value[0].len && value[0].data[0] == '\\') {
        value[0].len--;
        value[0].data++;
    }

    rv = ngx_hash_add_key(&ctx->keys, &value[0], var,
                          (ctx->hostnames) ? NGX_HASH_WILDCARD_KEY : 0);

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

    if (rv == NGX_DECLINED) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid hostname or wildcard \"%V\"", &value[0]);
    }

    if (rv == NGX_BUSY) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "conflicting parameter \"%V\"", &value[0]);
    }

    return NGX_CONF_ERROR;
}