ngx_http_userid_filter_module.c

Nginx是一个高性能的HTTP和反向代理服务器

    }

    if (conf->domain.len) {
        len += conf->domain.len;
    }

    cookie = ngx_palloc(r->pool, len);
    if (cookie == NULL) {
        return NGX_ERROR;
    }

    p = ngx_copy(cookie, conf->name.data, conf->name.len);
    *p++ = '=';

    if (ctx->uid_got[3] == 0) {
        src.len = 16;
        src.data = (u_char *) ctx->uid_set;
        dst.data = p;

        ngx_encode_base64(&dst, &src);

        p += dst.len;

        if (conf->mark) {
            *(p - 2) = conf->mark;
        }

    } else {
        p = ngx_cpymem(p, ctx->cookie.data, 22);
        *p++ = conf->mark;
        *p++ = '=';
    }

    if (conf->expires == NGX_HTTP_USERID_MAX_EXPIRES) {
        p = ngx_cpymem(p, expires, sizeof(expires) - 1);

    } else if (conf->expires) {
        p = ngx_cpymem(p, expires, sizeof("; expires=") - 1);
        p = ngx_http_cookie_time(p, ngx_time() + conf->expires);
    }

    p = ngx_copy(p, conf->domain.data, conf->domain.len);

    p = ngx_copy(p, conf->path.data, conf->path.len);

    set_cookie = ngx_list_push(&r->headers_out.headers);
    if (set_cookie == NULL) {
        return NGX_ERROR;
    }

    set_cookie->hash = 1;
    set_cookie->key.len = sizeof("Set-Cookie") - 1;
    set_cookie->key.data = (u_char *) "Set-Cookie";
    set_cookie->value.len = p - cookie;
    set_cookie->value.data = cookie;

    ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
                   "uid cookie: \"%V\"", &set_cookie->value);

    if (conf->p3p.len == 0) {
        return NGX_OK;
    }

    p3p = ngx_list_push(&r->headers_out.headers);
    if (p3p == NULL) {
        return NGX_ERROR;
    }

    p3p->hash = 1;
    p3p->key.len = sizeof("P3P") - 1;
    p3p->key.data = (u_char *) "P3P";
    p3p->value = conf->p3p;

    return NGX_OK;
}


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

    var = ngx_http_add_variable(cf, &ngx_http_userid_got, NGX_HTTP_VAR_NOHASH);
    if (var == NULL) {
        return NGX_ERROR;
    }

    var->get_handler = ngx_http_userid_variable;
    var->data = offsetof(ngx_http_userid_ctx_t, uid_got);

    var = ngx_http_add_variable(cf, &ngx_http_userid_set, NGX_HTTP_VAR_NOHASH);
    if (var == NULL) {
        return NGX_ERROR;
    }

    var->get_handler = ngx_http_userid_variable;
    var->data = offsetof(ngx_http_userid_ctx_t, uid_set);

    return NGX_OK;
}


static ngx_int_t
ngx_http_userid_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v,
    uintptr_t data)
{
    uint32_t                *uid;
    ngx_http_userid_ctx_t   *ctx;
    ngx_http_userid_conf_t  *conf;

    ctx = ngx_http_get_module_ctx(r, ngx_http_userid_filter_module);

    uid = (uint32_t *) ((char *) ctx + data);

    if (ctx == NULL || uid[3] == 0) {
        v->not_found = 1;
        return NGX_OK;
    }

    conf = ngx_http_get_module_loc_conf(r, ngx_http_userid_filter_module);

    v->len = conf->name.len + sizeof("=00001111222233334444555566667777") - 1;
    v->data = ngx_palloc(r->pool, v->len);
    if (v->data == NULL) {
        return NGX_ERROR;
    }

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

    ngx_sprintf(v->data, "%V=%08XD%08XD%08XD%08XD",
                &conf->name, uid[0], uid[1], uid[2], uid[3]);

    return NGX_OK;
}


static void *
ngx_http_userid_create_conf(ngx_conf_t *cf)
{
    ngx_http_userid_conf_t  *conf;

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

    /*
     * set by ngx_pcalloc():
     *
     *     conf->name.len = 0;
     *     conf->name.date = NULL;
     *     conf->domain.len = 0;
     *     conf->domain.date = NULL;
     *     conf->path.len = 0;
     *     conf->path.date = NULL;
     *     conf->p3p.len = 0;
     *     conf->p3p.date = NULL;
     */

    conf->enable = NGX_CONF_UNSET_UINT;
    conf->service = NGX_CONF_UNSET;
    conf->expires = NGX_CONF_UNSET;
    conf->mark = (u_char) '\xFF';

    return conf;
}


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

    ngx_conf_merge_uint_value(conf->enable, prev->enable,
                              NGX_HTTP_USERID_OFF);

    ngx_conf_merge_str_value(conf->name, prev->name, "uid");
    ngx_conf_merge_str_value(conf->domain, prev->domain, "");
    ngx_conf_merge_str_value(conf->path, prev->path, "; path=/");
    ngx_conf_merge_str_value(conf->p3p, prev->p3p, "");

    ngx_conf_merge_value(conf->service, prev->service, NGX_CONF_UNSET);
    ngx_conf_merge_sec_value(conf->expires, prev->expires, 0);

    if (conf->mark == (u_char) '\xFF') {
        if (prev->mark == (u_char) '\xFF') {
            conf->mark = '\0';
        } else {
            conf->mark = prev->mark;
        }
    }

    return NGX_CONF_OK;
}


static ngx_int_t
ngx_http_userid_init(ngx_conf_t *cf)
{
    ngx_http_next_header_filter = ngx_http_top_header_filter;
    ngx_http_top_header_filter = ngx_http_userid_filter;

    return NGX_OK;
}


static char *
ngx_http_userid_domain(ngx_conf_t *cf, void *post, void *data)
{
    ngx_str_t  *domain = data;

    u_char  *p, *new;

    if (ngx_strcmp(domain->data, "none") == 0) {
        domain->len = 0;
        domain->data = (u_char *) "";

        return NGX_CONF_OK;
    }

    new = ngx_palloc(cf->pool, sizeof("; domain=") - 1 + domain->len);
    if (new == NULL) {
        return NGX_CONF_ERROR;
    }

    p = ngx_cpymem(new, "; domain=", sizeof("; domain=") - 1);
    ngx_memcpy(p, domain->data, domain->len);

    domain->len += sizeof("; domain=") - 1;
    domain->data = new;

    return NGX_CONF_OK;
}


static char *
ngx_http_userid_path(ngx_conf_t *cf, void *post, void *data)
{
    ngx_str_t  *path = data;

    u_char  *p, *new;

    new = ngx_palloc(cf->pool, sizeof("; path=") - 1 + path->len);
    if (new == NULL) {
        return NGX_CONF_ERROR;
    }

    p = ngx_cpymem(new, "; path=", sizeof("; path=") - 1);
    ngx_memcpy(p, path->data, path->len);

    path->len += sizeof("; path=") - 1;
    path->data = new;

    return NGX_CONF_OK;
}


static char *
ngx_http_userid_expires(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_userid_conf_t *ucf = conf;

    ngx_str_t  *value;

    if (ucf->expires != NGX_CONF_UNSET) {
        return "is duplicate";
    }

    value = cf->args->elts;

    if (ngx_strcmp(value[1].data, "max") == 0) {
        ucf->expires = NGX_HTTP_USERID_MAX_EXPIRES;
        return NGX_CONF_OK;
    }

    if (ngx_strcmp(value[1].data, "off") == 0) {
        ucf->expires = 0;
        return NGX_CONF_OK;
    }

    ucf->expires = ngx_parse_time(&value[1], 1);
    if (ucf->expires == NGX_ERROR) {
        return "invalid value";
    }

    if (ucf->expires == NGX_PARSE_LARGE_TIME) {
        return "value must be less than 68 years";
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_userid_p3p(ngx_conf_t *cf, void *post, void *data)
{
    ngx_str_t  *p3p = data;

    if (ngx_strcmp(p3p->data, "none") == 0) {
        p3p->len = 0;
        p3p->data = (u_char *) "";
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_userid_mark(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_userid_conf_t *ucf = conf;

    ngx_str_t  *value;

    if (ucf->mark != (u_char) '\xFF') {
        return "is duplicate";
    }

    value = cf->args->elts;

    if (ngx_strcmp(value[1].data, "off") == 0) {
        ucf->mark = '\0';
        return NGX_CONF_OK;
    }

    if (value[1].len != 1
        || !((value[1].data[0] >= '0' && value[1].data[0] <= '9')
              || (value[1].data[0] >= 'A' && value[1].data[0] <= 'Z')
              || (value[1].data[0] >= 'a' && value[1].data[0] <= 'z')
              || value[1].data[0] == '='))
    {
        return "value must be \"off\" or a single letter, digit or \"=\"";
    }

    ucf->mark = value[1].data[0];

    return NGX_CONF_OK;
}


static ngx_int_t
ngx_http_userid_init_worker(ngx_cycle_t *cycle)
{
    struct timeval  tp;

    ngx_gettimeofday(&tp);

    /* use the most significant usec part that fits to 16 bits */
    start_value = ((tp.tv_usec / 20) << 16) | ngx_pid;

    return NGX_OK;
}