view src/stream/ngx_stream_access_module.c @ 6749:f88a145b093e stable-1.10

HTTP/2: the "421 Misdirected Request" response (closes #848). Since 4fbef397c753 nginx rejects with the 400 error any attempts of requesting different host over the same connection, if the relevant virtual server requires verification of a client certificate. While requesting hosts other than negotiated isn't something legal in HTTP/1.x, the HTTP/2 specification explicitly permits such requests for connection reuse and has introduced a special response code 421. According to RFC 7540 Section 9.1.2 this code can be sent by a server that is not configured to produce responses for the combination of scheme and authority that are included in the request URI. And the client may retry the request over a different connection. Now this code is used for requests that aren't authorized in current connection. After receiving the 421 response a client will be able to open a new connection, provide the required certificate and retry the request. Unfortunately, not all clients currently are able to handle it well. Notably Chrome just shows an error, while at least the latest version of Firefox retries the request over a new connection.
author Valentin Bartenev <vbart@nginx.com>
date Fri, 20 May 2016 18:41:17 +0300
parents 8807a2369b1a
children 2f41d383c9c7
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 {
    in_addr_t         mask;
    in_addr_t         addr;
    ngx_uint_t        deny;      /* unsigned  deny:1; */
} ngx_stream_access_rule_t;

#if (NGX_HAVE_INET6)

typedef struct {
    struct in6_addr   addr;
    struct in6_addr   mask;
    ngx_uint_t        deny;      /* unsigned  deny:1; */
} ngx_stream_access_rule6_t;

#endif

#if (NGX_HAVE_UNIX_DOMAIN)

typedef struct {
    ngx_uint_t        deny;      /* unsigned  deny:1; */
} ngx_stream_access_rule_un_t;

#endif

typedef struct {
    ngx_array_t      *rules;     /* array of ngx_stream_access_rule_t */
#if (NGX_HAVE_INET6)
    ngx_array_t      *rules6;    /* array of ngx_stream_access_rule6_t */
#endif
#if (NGX_HAVE_UNIX_DOMAIN)
    ngx_array_t      *rules_un;  /* array of ngx_stream_access_rule_un_t */
#endif
} ngx_stream_access_srv_conf_t;


static ngx_int_t ngx_stream_access_handler(ngx_stream_session_t *s);
static ngx_int_t ngx_stream_access_inet(ngx_stream_session_t *s,
    ngx_stream_access_srv_conf_t *ascf, in_addr_t addr);
#if (NGX_HAVE_INET6)
static ngx_int_t ngx_stream_access_inet6(ngx_stream_session_t *s,
    ngx_stream_access_srv_conf_t *ascf, u_char *p);
#endif
#if (NGX_HAVE_UNIX_DOMAIN)
static ngx_int_t ngx_stream_access_unix(ngx_stream_session_t *s,
    ngx_stream_access_srv_conf_t *ascf);
#endif
static ngx_int_t ngx_stream_access_found(ngx_stream_session_t *s,
    ngx_uint_t deny);
static char *ngx_stream_access_rule(ngx_conf_t *cf, ngx_command_t *cmd,
    void *conf);
static void *ngx_stream_access_create_srv_conf(ngx_conf_t *cf);
static char *ngx_stream_access_merge_srv_conf(ngx_conf_t *cf,
    void *parent, void *child);
static ngx_int_t ngx_stream_access_init(ngx_conf_t *cf);


static ngx_command_t  ngx_stream_access_commands[] = {

    { ngx_string("allow"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_stream_access_rule,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

    { ngx_string("deny"),
      NGX_STREAM_MAIN_CONF|NGX_STREAM_SRV_CONF|NGX_CONF_TAKE1,
      ngx_stream_access_rule,
      NGX_STREAM_SRV_CONF_OFFSET,
      0,
      NULL },

      ngx_null_command
};



static ngx_stream_module_t  ngx_stream_access_module_ctx = {
    ngx_stream_access_init,                /* postconfiguration */

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

    ngx_stream_access_create_srv_conf,     /* create server configuration */
    ngx_stream_access_merge_srv_conf       /* merge server configuration */
};


ngx_module_t  ngx_stream_access_module = {
    NGX_MODULE_V1,
    &ngx_stream_access_module_ctx,         /* module context */
    ngx_stream_access_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_access_handler(ngx_stream_session_t *s)
{
    struct sockaddr_in            *sin;
    ngx_stream_access_srv_conf_t  *ascf;
#if (NGX_HAVE_INET6)
    u_char                        *p;
    in_addr_t                      addr;
    struct sockaddr_in6           *sin6;
#endif

    ascf = ngx_stream_get_module_srv_conf(s, ngx_stream_access_module);

    switch (s->connection->sockaddr->sa_family) {

    case AF_INET:
        if (ascf->rules) {
            sin = (struct sockaddr_in *) s->connection->sockaddr;
            return ngx_stream_access_inet(s, ascf, sin->sin_addr.s_addr);
        }
        break;

#if (NGX_HAVE_INET6)

    case AF_INET6:
        sin6 = (struct sockaddr_in6 *) s->connection->sockaddr;
        p = sin6->sin6_addr.s6_addr;

        if (ascf->rules && IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
            addr = p[12] << 24;
            addr += p[13] << 16;
            addr += p[14] << 8;
            addr += p[15];
            return ngx_stream_access_inet(s, ascf, htonl(addr));
        }

        if (ascf->rules6) {
            return ngx_stream_access_inet6(s, ascf, p);
        }

        break;

#endif

#if (NGX_HAVE_UNIX_DOMAIN)

    case AF_UNIX:
        if (ascf->rules_un) {
            return ngx_stream_access_unix(s, ascf);
        }

        break;

#endif
    }

    return NGX_DECLINED;
}


static ngx_int_t
ngx_stream_access_inet(ngx_stream_session_t *s,
    ngx_stream_access_srv_conf_t *ascf, in_addr_t addr)
{
    ngx_uint_t                 i;
    ngx_stream_access_rule_t  *rule;

    rule = ascf->rules->elts;
    for (i = 0; i < ascf->rules->nelts; i++) {

        ngx_log_debug3(NGX_LOG_DEBUG_STREAM, s->connection->log, 0,
                       "access: %08XD %08XD %08XD",
                       addr, rule[i].mask, rule[i].addr);

        if ((addr & rule[i].mask) == rule[i].addr) {
            return ngx_stream_access_found(s, rule[i].deny);
        }
    }

    return NGX_DECLINED;
}


#if (NGX_HAVE_INET6)

static ngx_int_t
ngx_stream_access_inet6(ngx_stream_session_t *s,
    ngx_stream_access_srv_conf_t *ascf, u_char *p)
{
    ngx_uint_t                  n;
    ngx_uint_t                  i;
    ngx_stream_access_rule6_t  *rule6;

    rule6 = ascf->rules6->elts;
    for (i = 0; i < ascf->rules6->nelts; i++) {

#if (NGX_DEBUG)
        {
        size_t  cl, ml, al;
        u_char  ct[NGX_INET6_ADDRSTRLEN];
        u_char  mt[NGX_INET6_ADDRSTRLEN];
        u_char  at[NGX_INET6_ADDRSTRLEN];

        cl = ngx_inet6_ntop(p, ct, NGX_INET6_ADDRSTRLEN);
        ml = ngx_inet6_ntop(rule6[i].mask.s6_addr, mt, NGX_INET6_ADDRSTRLEN);
        al = ngx_inet6_ntop(rule6[i].addr.s6_addr, at, NGX_INET6_ADDRSTRLEN);

        ngx_log_debug6(NGX_LOG_DEBUG_STREAM, s->connection->log, 0,
                       "access: %*s %*s %*s", cl, ct, ml, mt, al, at);
        }
#endif

        for (n = 0; n < 16; n++) {
            if ((p[n] & rule6[i].mask.s6_addr[n]) != rule6[i].addr.s6_addr[n]) {
                goto next;
            }
        }

        return ngx_stream_access_found(s, rule6[i].deny);

    next:
        continue;
    }

    return NGX_DECLINED;
}

#endif


#if (NGX_HAVE_UNIX_DOMAIN)

static ngx_int_t
ngx_stream_access_unix(ngx_stream_session_t *s,
    ngx_stream_access_srv_conf_t *ascf)
{
    ngx_uint_t                    i;
    ngx_stream_access_rule_un_t  *rule_un;

    rule_un = ascf->rules_un->elts;
    for (i = 0; i < ascf->rules_un->nelts; i++) {

        /* TODO: check path */
        if (1) {
            return ngx_stream_access_found(s, rule_un[i].deny);
        }
    }

    return NGX_DECLINED;
}

#endif


static ngx_int_t
ngx_stream_access_found(ngx_stream_session_t *s, ngx_uint_t deny)
{
    if (deny) {
        ngx_log_error(NGX_LOG_ERR, s->connection->log, 0,
                      "access forbidden by rule");
        return NGX_ABORT;
    }

    return NGX_OK;
}


static char *
ngx_stream_access_rule(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_stream_access_srv_conf_t *ascf = conf;

    ngx_int_t                     rc;
    ngx_uint_t                    all;
    ngx_str_t                    *value;
    ngx_cidr_t                    cidr;
    ngx_stream_access_rule_t     *rule;
#if (NGX_HAVE_INET6)
    ngx_stream_access_rule6_t    *rule6;
#endif
#if (NGX_HAVE_UNIX_DOMAIN)
    ngx_stream_access_rule_un_t  *rule_un;
#endif

    ngx_memzero(&cidr, sizeof(ngx_cidr_t));

    value = cf->args->elts;

    all = (value[1].len == 3 && ngx_strcmp(value[1].data, "all") == 0);

    if (!all) {

#if (NGX_HAVE_UNIX_DOMAIN)

        if (value[1].len == 5 && ngx_strcmp(value[1].data, "unix:") == 0) {
            cidr.family = AF_UNIX;
            rc = NGX_OK;

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

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

        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]);
        }
    }

    if (cidr.family == AF_INET || all) {

        if (ascf->rules == NULL) {
            ascf->rules = ngx_array_create(cf->pool, 4,
                                           sizeof(ngx_stream_access_rule_t));
            if (ascf->rules == NULL) {
                return NGX_CONF_ERROR;
            }
        }

        rule = ngx_array_push(ascf->rules);
        if (rule == NULL) {
            return NGX_CONF_ERROR;
        }

        rule->mask = cidr.u.in.mask;
        rule->addr = cidr.u.in.addr;
        rule->deny = (value[0].data[0] == 'd') ? 1 : 0;
    }

#if (NGX_HAVE_INET6)
    if (cidr.family == AF_INET6 || all) {

        if (ascf->rules6 == NULL) {
            ascf->rules6 = ngx_array_create(cf->pool, 4,
                                            sizeof(ngx_stream_access_rule6_t));
            if (ascf->rules6 == NULL) {
                return NGX_CONF_ERROR;
            }
        }

        rule6 = ngx_array_push(ascf->rules6);
        if (rule6 == NULL) {
            return NGX_CONF_ERROR;
        }

        rule6->mask = cidr.u.in6.mask;
        rule6->addr = cidr.u.in6.addr;
        rule6->deny = (value[0].data[0] == 'd') ? 1 : 0;
    }
#endif

#if (NGX_HAVE_UNIX_DOMAIN)
    if (cidr.family == AF_UNIX || all) {

        if (ascf->rules_un == NULL) {
            ascf->rules_un = ngx_array_create(cf->pool, 1,
                                          sizeof(ngx_stream_access_rule_un_t));
            if (ascf->rules_un == NULL) {
                return NGX_CONF_ERROR;
            }
        }

        rule_un = ngx_array_push(ascf->rules_un);
        if (rule_un == NULL) {
            return NGX_CONF_ERROR;
        }

        rule_un->deny = (value[0].data[0] == 'd') ? 1 : 0;
    }
#endif

    return NGX_CONF_OK;
}


static void *
ngx_stream_access_create_srv_conf(ngx_conf_t *cf)
{
    ngx_stream_access_srv_conf_t  *conf;

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

    return conf;
}


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

    if (conf->rules == NULL
#if (NGX_HAVE_INET6)
        && conf->rules6 == NULL
#endif
#if (NGX_HAVE_UNIX_DOMAIN)
        && conf->rules_un == NULL
#endif
    ) {
        conf->rules = prev->rules;
#if (NGX_HAVE_INET6)
        conf->rules6 = prev->rules6;
#endif
#if (NGX_HAVE_UNIX_DOMAIN)
        conf->rules_un = prev->rules_un;
#endif
    }

    return NGX_CONF_OK;
}


static ngx_int_t
ngx_stream_access_init(ngx_conf_t *cf)
{
    ngx_stream_core_main_conf_t  *cmcf;

    cmcf = ngx_stream_conf_get_module_main_conf(cf, ngx_stream_core_module);
    cmcf->access_handler = ngx_stream_access_handler;

    return NGX_OK;
}