view src/http/modules/ngx_http_secure_link_module.c @ 6927:c36d160cd4e0

Access log: removed dead ev->timedout check in flush timer handler. The ev->timedout flag is set on first timer expiration, and never reset after it. Due to this the code to stop the timer when the timer was canceled never worked (except in a very specific time frame immediately after start), and the timer was always armed again. This essentially resulted in a buffer flush at the end of an event loop iteration. This behaviour actually seems to be better than just stopping the flush timer for the whole shutdown, so it is preserved as is instead of fixing the code to actually remove the timer. It will be further improved by upcoming changes to preserve cancelable timers if there are other timers blocking shutdown.
author Maxim Dounin <mdounin@mdounin.ru>
date Tue, 07 Mar 2017 18:51:12 +0300
parents d89442dab4d1
children c7d4017c8876
line wrap: on
line source


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


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>
#include <ngx_md5.h>


typedef struct {
    ngx_http_complex_value_t  *variable;
    ngx_http_complex_value_t  *md5;
    ngx_str_t                  secret;
} ngx_http_secure_link_conf_t;


typedef struct {
    ngx_str_t                  expires;
} ngx_http_secure_link_ctx_t;


static ngx_int_t ngx_http_secure_link_old_variable(ngx_http_request_t *r,
    ngx_http_secure_link_conf_t *conf, ngx_http_variable_value_t *v,
    uintptr_t data);
static ngx_int_t ngx_http_secure_link_expires_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data);
static void *ngx_http_secure_link_create_conf(ngx_conf_t *cf);
static char *ngx_http_secure_link_merge_conf(ngx_conf_t *cf, void *parent,
    void *child);
static ngx_int_t ngx_http_secure_link_add_variables(ngx_conf_t *cf);


static ngx_command_t  ngx_http_secure_link_commands[] = {

    { ngx_string("secure_link"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
      ngx_http_set_complex_value_slot,
      NGX_HTTP_LOC_CONF_OFFSET,
      offsetof(ngx_http_secure_link_conf_t, variable),
      NULL },

    { ngx_string("secure_link_md5"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
      ngx_http_set_complex_value_slot,
      NGX_HTTP_LOC_CONF_OFFSET,
      offsetof(ngx_http_secure_link_conf_t, md5),
      NULL },

    { ngx_string("secure_link_secret"),
      NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
      ngx_conf_set_str_slot,
      NGX_HTTP_LOC_CONF_OFFSET,
      offsetof(ngx_http_secure_link_conf_t, secret),
      NULL },

      ngx_null_command
};


static ngx_http_module_t  ngx_http_secure_link_module_ctx = {
    ngx_http_secure_link_add_variables,    /* preconfiguration */
    NULL,                                  /* postconfiguration */

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

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

    ngx_http_secure_link_create_conf,      /* create location configuration */
    ngx_http_secure_link_merge_conf        /* merge location configuration */
};


ngx_module_t  ngx_http_secure_link_module = {
    NGX_MODULE_V1,
    &ngx_http_secure_link_module_ctx,      /* module context */
    ngx_http_secure_link_commands,         /* module directives */
    NGX_HTTP_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_str_t  ngx_http_secure_link_name = ngx_string("secure_link");
static ngx_str_t  ngx_http_secure_link_expires_name =
    ngx_string("secure_link_expires");


static ngx_int_t
ngx_http_secure_link_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    u_char                       *p, *last;
    ngx_str_t                     val, hash;
    time_t                        expires;
    ngx_md5_t                     md5;
    ngx_http_secure_link_ctx_t   *ctx;
    ngx_http_secure_link_conf_t  *conf;
    u_char                        hash_buf[16], md5_buf[16];

    conf = ngx_http_get_module_loc_conf(r, ngx_http_secure_link_module);

    if (conf->secret.data) {
        return ngx_http_secure_link_old_variable(r, conf, v, data);
    }

    if (conf->variable == NULL || conf->md5 == NULL) {
        goto not_found;
    }

    if (ngx_http_complex_value(r, conf->variable, &val) != NGX_OK) {
        return NGX_ERROR;
    }

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "secure link: \"%V\"", &val);

    last = val.data + val.len;

    p = ngx_strlchr(val.data, last, ',');
    expires = 0;

    if (p) {
        val.len = p++ - val.data;

        expires = ngx_atotm(p, last - p);
        if (expires <= 0) {
            goto not_found;
        }

        ctx = ngx_pcalloc(r->pool, sizeof(ngx_http_secure_link_ctx_t));
        if (ctx == NULL) {
            return NGX_ERROR;
        }

        ngx_http_set_ctx(r, ctx, ngx_http_secure_link_module);

        ctx->expires.len = last - p;
        ctx->expires.data = p;
    }

    if (val.len > 24) {
        goto not_found;
    }

    hash.len = 16;
    hash.data = hash_buf;

    if (ngx_decode_base64url(&hash, &val) != NGX_OK) {
        goto not_found;
    }

    if (hash.len != 16) {
        goto not_found;
    }

    if (ngx_http_complex_value(r, conf->md5, &val) != NGX_OK) {
        return NGX_ERROR;
    }

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "secure link md5: \"%V\"", &val);

    ngx_md5_init(&md5);
    ngx_md5_update(&md5, val.data, val.len);
    ngx_md5_final(md5_buf, &md5);

    if (ngx_memcmp(hash_buf, md5_buf, 16) != 0) {
        goto not_found;
    }

    v->data = (u_char *) ((expires && expires < ngx_time()) ? "0" : "1");
    v->len = 1;
    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;

    return NGX_OK;

not_found:

    v->not_found = 1;

    return NGX_OK;
}


static ngx_int_t
ngx_http_secure_link_old_variable(ngx_http_request_t *r,
    ngx_http_secure_link_conf_t *conf, ngx_http_variable_value_t *v,
    uintptr_t data)
{
    u_char      *p, *start, *end, *last;
    size_t       len;
    ngx_int_t    n;
    ngx_uint_t   i;
    ngx_md5_t    md5;
    u_char       hash[16];

    p = &r->unparsed_uri.data[1];
    last = r->unparsed_uri.data + r->unparsed_uri.len;

    while (p < last) {
        if (*p++ == '/') {
            start = p;
            goto md5_start;
        }
    }

    goto not_found;

md5_start:

    while (p < last) {
        if (*p++ == '/') {
            end = p - 1;
            goto url_start;
        }
    }

    goto not_found;

url_start:

    len = last - p;

    if (end - start != 32 || len == 0) {
        goto not_found;
    }

    ngx_md5_init(&md5);
    ngx_md5_update(&md5, p, len);
    ngx_md5_update(&md5, conf->secret.data, conf->secret.len);
    ngx_md5_final(hash, &md5);

    for (i = 0; i < 16; i++) {
        n = ngx_hextoi(&start[2 * i], 2);
        if (n == NGX_ERROR || n != hash[i]) {
            goto not_found;
        }
    }

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

    return NGX_OK;

not_found:

    v->not_found = 1;

    return NGX_OK;
}


static ngx_int_t
ngx_http_secure_link_expires_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    ngx_http_secure_link_ctx_t  *ctx;

    ctx = ngx_http_get_module_ctx(r, ngx_http_secure_link_module);

    if (ctx) {
        v->len = ctx->expires.len;
        v->valid = 1;
        v->no_cacheable = 0;
        v->not_found = 0;
        v->data = ctx->expires.data;

    } else {
        v->not_found = 1;
    }

    return NGX_OK;
}


static void *
ngx_http_secure_link_create_conf(ngx_conf_t *cf)
{
    ngx_http_secure_link_conf_t  *conf;

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

    /*
     * set by ngx_pcalloc():
     *
     *     conf->variable = NULL;
     *     conf->md5 = NULL;
     *     conf->secret = { 0, NULL };
     */

    return conf;
}


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

    if (conf->secret.data) {
        if (conf->variable || conf->md5) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "\"secure_link_secret\" cannot be mixed with "
                               "\"secure_link\" and \"secure_link_md5\"");
            return NGX_CONF_ERROR;
        }

        return NGX_CONF_OK;
    }

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

    if (conf->md5 == NULL) {
        conf->md5 = prev->md5;
    }

    if (conf->variable == NULL && conf->md5 == NULL) {
        conf->secret = prev->secret;
    }

    return NGX_CONF_OK;
}


static ngx_int_t
ngx_http_secure_link_add_variables(ngx_conf_t *cf)
{
    ngx_http_variable_t  *var;

    var = ngx_http_add_variable(cf, &ngx_http_secure_link_name, 0);
    if (var == NULL) {
        return NGX_ERROR;
    }

    var->get_handler = ngx_http_secure_link_variable;

    var = ngx_http_add_variable(cf, &ngx_http_secure_link_expires_name, 0);
    if (var == NULL) {
        return NGX_ERROR;
    }

    var->get_handler = ngx_http_secure_link_expires_variable;

    return NGX_OK;
}