view src/stream/ngx_stream_realip_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 3908156a51fa
children df1a62c83b1b
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_array_t       *from;     /* array of ngx_cidr_t */
} ngx_stream_realip_srv_conf_t;


typedef struct {
    struct sockaddr   *sockaddr;
    socklen_t          socklen;
    ngx_str_t          addr_text;
} ngx_stream_realip_ctx_t;


static ngx_int_t ngx_stream_realip_handler(ngx_stream_session_t *s);
static ngx_int_t ngx_stream_realip_set_addr(ngx_stream_session_t *s,
    ngx_addr_t *addr);
static char *ngx_stream_realip_from(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static void *ngx_stream_realip_create_srv_conf(ngx_conf_t *cf);
static char *ngx_stream_realip_merge_srv_conf(ngx_conf_t *cf, void *parent,
    void *child);
static ngx_int_t ngx_stream_realip_add_variables(ngx_conf_t *cf);
static ngx_int_t ngx_stream_realip_init(ngx_conf_t *cf);


static ngx_int_t ngx_stream_realip_remote_addr_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data);
static ngx_int_t ngx_stream_realip_remote_port_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data);


static ngx_command_t  ngx_stream_realip_commands[] = {

    { ngx_string("set_real_ip_from"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_stream_realip_from,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

      ngx_null_command
};


static ngx_stream_module_t  ngx_stream_realip_module_ctx = {
    ngx_stream_realip_add_variables,       /* preconfiguration */
    ngx_stream_realip_init,                /* postconfiguration */

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

    ngx_stream_realip_create_srv_conf,     /* create server configuration */
    ngx_stream_realip_merge_srv_conf       /* merge server configuration */
};


ngx_module_t  ngx_stream_realip_module = {
    NGX_MODULE_V1,
    &ngx_stream_realip_module_ctx,         /* module context */
    ngx_stream_realip_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_realip_vars[] = {

    { ngx_string("realip_remote_addr"), NULL,
      ngx_stream_realip_remote_addr_variable, 0, 0, 0 },

    { ngx_string("realip_remote_port"), NULL,
      ngx_stream_realip_remote_port_variable, 0, 0, 0 },

    { ngx_null_string, NULL, NULL, 0, 0, 0 }
};


static ngx_int_t
ngx_stream_realip_handler(ngx_stream_session_t *s)
{
    ngx_addr_t                     addr;
    ngx_connection_t              *c;
    ngx_stream_realip_srv_conf_t  *rscf;

    rscf = ngx_stream_get_module_srv_conf(s, ngx_stream_realip_module);

    if (rscf->from == NULL) {
        return NGX_DECLINED;
    }

    c = s->connection;

    if (c->proxy_protocol_addr.len == 0) {
        return NGX_DECLINED;
    }

    if (ngx_cidr_match(c->sockaddr, rscf->from) != NGX_OK) {
        return NGX_DECLINED;
    }

    if (ngx_parse_addr(c->pool, &addr, c->proxy_protocol_addr.data,
                       c->proxy_protocol_addr.len)
        != NGX_OK)
    {
        return NGX_DECLINED;
    }

    ngx_inet_set_port(addr.sockaddr, c->proxy_protocol_port);

    return ngx_stream_realip_set_addr(s, &addr);
}


static ngx_int_t
ngx_stream_realip_set_addr(ngx_stream_session_t *s, ngx_addr_t *addr)
{
    size_t                    len;
    u_char                   *p;
    u_char                    text[NGX_SOCKADDR_STRLEN];
    ngx_connection_t         *c;
    ngx_stream_realip_ctx_t  *ctx;

    c = s->connection;

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

    len = ngx_sock_ntop(addr->sockaddr, addr->socklen, text,
                        NGX_SOCKADDR_STRLEN, 0);
    if (len == 0) {
        return NGX_ERROR;
    }

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

    ngx_memcpy(p, text, len);

    ngx_stream_set_ctx(s, ctx, ngx_stream_realip_module);

    ctx->sockaddr = c->sockaddr;
    ctx->socklen = c->socklen;
    ctx->addr_text = c->addr_text;

    c->sockaddr = addr->sockaddr;
    c->socklen = addr->socklen;
    c->addr_text.len = len;
    c->addr_text.data = p;

    return NGX_DECLINED;
}


static char *
ngx_stream_realip_from(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_realip_srv_conf_t *rscf = conf;

    ngx_int_t                rc;
    ngx_str_t               *value;
    ngx_cidr_t              *cidr;

    value = cf->args->elts;

    if (rscf->from == NULL) {
        rscf->from = ngx_array_create(cf->pool, 2,
                                      sizeof(ngx_cidr_t));
        if (rscf->from == NULL) {
            return NGX_CONF_ERROR;
        }
    }

    cidr = ngx_array_push(rscf->from);
    if (cidr == NULL) {
        return NGX_CONF_ERROR;
    }

#if (NGX_HAVE_UNIX_DOMAIN)

    if (ngx_strcmp(value[1].data, "unix:") == 0) {
        cidr->family = AF_UNIX;
        return NGX_CONF_OK;
    }

#endif

    rc = ngx_ptocidr(&value[1], cidr);

    if (rc == NGX_ERROR) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%V\"",
                           &value[1]);
        return NGX_CONF_ERROR;
    }

    if (rc == NGX_DONE) {
        ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
                           "low address bits of %V are meaningless", &value[1]);
    }

    return NGX_CONF_OK;
}


static void *
ngx_stream_realip_create_srv_conf(ngx_conf_t *cf)
{
    ngx_stream_realip_srv_conf_t  *conf;

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

    /*
     * set by ngx_pcalloc():
     *
     *     conf->from = NULL;
     */

    return conf;
}


static char *
ngx_stream_realip_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
{
    ngx_stream_realip_srv_conf_t *prev = parent;
    ngx_stream_realip_srv_conf_t *conf = child;

    if (conf->from == NULL) {
        conf->from = prev->from;
    }

    return NGX_CONF_OK;
}


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

    for (v = ngx_stream_realip_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_realip_init(ngx_conf_t *cf)
{
    ngx_stream_handler_pt        *h;
    ngx_stream_core_main_conf_t  *cmcf;

    cmcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_core_module);

    h = ngx_array_push(&cmcf->phases[NGX_STREAM_POST_ACCEPT_PHASE].handlers);
    if (h == NULL) {
        return NGX_ERROR;
    }

    *h = ngx_stream_realip_handler;

    return NGX_OK;
}


static ngx_int_t
ngx_stream_realip_remote_addr_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data)
{
    ngx_str_t                *addr_text;
    ngx_stream_realip_ctx_t  *ctx;

    ctx = ngx_stream_get_module_ctx(s, ngx_stream_realip_module);

    addr_text = ctx ? &ctx->addr_text : &s->connection->addr_text;

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

    return NGX_OK;
}


static ngx_int_t
ngx_stream_realip_remote_port_variable(ngx_stream_session_t *s,
    ngx_stream_variable_value_t *v, uintptr_t data)
{
    ngx_uint_t                port;
    struct sockaddr          *sa;
    ngx_stream_realip_ctx_t  *ctx;

    ctx = ngx_stream_get_module_ctx(s, ngx_stream_realip_module);

    sa = ctx ? ctx->sockaddr : s->connection->sockaddr;

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

    v->data = ngx_pnalloc(s->connection->pool, sizeof("65535") - 1);
    if (v->data == NULL) {
        return NGX_ERROR;
    }

    port = ngx_inet_get_port(sa);

    if (port > 0 && port < 65536) {
        v->len = ngx_sprintf(v->data, "%ui", port) - v->data;
    }

    return NGX_OK;
}