ngx_http_proxy_module.c

nginx 反向代理0.7.1版本 用于实现反向代理

static ngx_int_t
ngx_http_proxy_port_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    ngx_http_proxy_ctx_t  *ctx;

    ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);

    if (ctx == NULL) {
        v->not_found = 1;
        return NGX_OK;
    }

    v->len = ctx->vars.port.len;
    v->valid = 1;
    v->no_cacheable = 0;
    v->not_found = 0;
    v->data = ctx->vars.port.data;

    return NGX_OK;
}


static ngx_int_t
ngx_http_proxy_add_x_forwarded_for_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    u_char  *p;

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

    if (r->headers_in.x_forwarded_for == NULL) {
        v->len = r->connection->addr_text.len;
        v->data = r->connection->addr_text.data;
        return NGX_OK;
    }

    v->len = r->headers_in.x_forwarded_for->value.len
             + sizeof(", ") - 1 + r->connection->addr_text.len;

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

    v->data = p;

    p = ngx_copy(p, r->headers_in.x_forwarded_for->value.data,
                 r->headers_in.x_forwarded_for->value.len);

    *p++ = ','; *p++ = ' ';

    ngx_memcpy(p, r->connection->addr_text.data, r->connection->addr_text.len);

    return NGX_OK;
}


static ngx_int_t
ngx_http_proxy_internal_body_length_variable(ngx_http_request_t *r,
    ngx_http_variable_value_t *v, uintptr_t data)
{
    ngx_http_proxy_ctx_t  *ctx;

    ctx = ngx_http_get_module_ctx(r, ngx_http_proxy_module);

    if (ctx == NULL) {
        v->not_found = 1;
        return NGX_OK;
    }

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

    v->data = ngx_palloc(r->connection->pool, NGX_SIZE_T_LEN);

    if (v->data == NULL) {
        return NGX_ERROR;
    }

    v->len = ngx_sprintf(v->data, "%uz", ctx->internal_body_length) - v->data;

    return NGX_OK;
}


static ngx_int_t
ngx_http_proxy_rewrite_redirect(ngx_http_request_t *r, ngx_table_elt_t *h,
    size_t prefix)
{
    ngx_int_t                   rc;
    ngx_uint_t                  i;
    ngx_http_proxy_loc_conf_t  *plcf;
    ngx_http_proxy_redirect_t  *pr;

    plcf = ngx_http_get_module_loc_conf(r, ngx_http_proxy_module);

    pr = plcf->redirects->elts;

    if (pr == NULL) {
        return NGX_DECLINED;
    }

    for (i = 0; i < plcf->redirects->nelts; i++) {
        rc = pr[i].handler(r, h, prefix, &pr[i]);

        if (rc != NGX_DECLINED) {
            return rc;
        }
    }

    return NGX_DECLINED;
}


static ngx_int_t
ngx_http_proxy_rewrite_redirect_text(ngx_http_request_t *r, ngx_table_elt_t *h,
    size_t prefix, ngx_http_proxy_redirect_t *pr)
{
    size_t   len;
    u_char  *data, *p;

    if (pr->redirect.len > h->value.len - prefix
        || ngx_rstrncmp(h->value.data + prefix, pr->redirect.data,
                        pr->redirect.len) != 0)
    {
        return NGX_DECLINED;
    }

    len = prefix + pr->replacement.text.len + h->value.len - pr->redirect.len;

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

    p = data;

    p = ngx_copy(p, h->value.data, prefix);

    if (pr->replacement.text.len) {
        p = ngx_copy(p, pr->replacement.text.data, pr->replacement.text.len);
    }

    ngx_memcpy(p, h->value.data + prefix + pr->redirect.len,
               h->value.len - pr->redirect.len - prefix);

    h->value.len = len;
    h->value.data = data;

    return NGX_OK;
}


static ngx_int_t
ngx_http_proxy_rewrite_redirect_vars(ngx_http_request_t *r, ngx_table_elt_t *h,
    size_t prefix, ngx_http_proxy_redirect_t *pr)
{
    size_t                        len;
    u_char                       *data, *p;
    ngx_http_script_code_pt       code;
    ngx_http_script_engine_t      e;
    ngx_http_script_len_code_pt   lcode;

    if (pr->redirect.len > h->value.len - prefix
        || ngx_rstrncmp(h->value.data + prefix, pr->redirect.data,
                        pr->redirect.len) != 0)
    {
        return NGX_DECLINED;
    }

    ngx_memzero(&e, sizeof(ngx_http_script_engine_t));

    e.ip = pr->replacement.vars.lengths;
    e.request = r;

    len = prefix + h->value.len - pr->redirect.len;

    while (*(uintptr_t *) e.ip) {
        lcode = *(ngx_http_script_len_code_pt *) e.ip;
        len += lcode(&e);
    }

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

    p = data;

    p = ngx_copy(p, h->value.data, prefix);

    e.ip = pr->replacement.vars.values;
    e.pos = p;

    while (*(uintptr_t *) e.ip) {
        code = *(ngx_http_script_code_pt *) e.ip;
        code(&e);
    }

    ngx_memcpy(e.pos, h->value.data + prefix + pr->redirect.len,
               h->value.len - pr->redirect.len - prefix);

    h->value.len = len;
    h->value.data = data;

    return NGX_OK;
}


static ngx_int_t
ngx_http_proxy_add_variables(ngx_conf_t *cf)
{
    ngx_http_variable_t  *var, *v;

    for (v = ngx_http_proxy_vars; v->name.len; v++) {
        var = ngx_http_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 void *
ngx_http_proxy_create_loc_conf(ngx_conf_t *cf)
{
    ngx_http_proxy_loc_conf_t  *conf;

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

    /*
     * set by ngx_pcalloc():
     *
     *     conf->upstream.bufs.num = 0;
     *     conf->upstream.next_upstream = 0;
     *     conf->upstream.temp_path = NULL;
     *     conf->upstream.hide_headers_hash = { NULL, 0 };
     *     conf->upstream.schema = { 0, NULL };
     *     conf->upstream.uri = { 0, NULL };
     *     conf->upstream.location = NULL;
     *     conf->upstream.store_lengths = NULL;
     *     conf->upstream.store_values = NULL;
     *
     *     conf->method = NULL;
     *     conf->headers_source = NULL;
     *     conf->headers_set_len = NULL;
     *     conf->headers_set = NULL;
     *     conf->headers_set_hash = NULL;
     *     conf->body_set_len = NULL;
     *     conf->body_set = NULL;
     *     conf->body_source = { 0, NULL };
     *     conf->rewrite_locations = NULL;
     */

    conf->upstream.store = NGX_CONF_UNSET;
    conf->upstream.store_access = NGX_CONF_UNSET_UINT;
    conf->upstream.buffering = NGX_CONF_UNSET;
    conf->upstream.ignore_client_abort = NGX_CONF_UNSET;

    conf->upstream.connect_timeout = NGX_CONF_UNSET_MSEC;
    conf->upstream.send_timeout = NGX_CONF_UNSET_MSEC;
    conf->upstream.read_timeout = NGX_CONF_UNSET_MSEC;

    conf->upstream.send_lowat = NGX_CONF_UNSET_SIZE;
    conf->upstream.buffer_size = NGX_CONF_UNSET_SIZE;

    conf->upstream.busy_buffers_size_conf = NGX_CONF_UNSET_SIZE;
    conf->upstream.max_temp_file_size_conf = NGX_CONF_UNSET_SIZE;
    conf->upstream.temp_file_write_size_conf = NGX_CONF_UNSET_SIZE;

    conf->upstream.pass_request_headers = NGX_CONF_UNSET;
    conf->upstream.pass_request_body = NGX_CONF_UNSET;

    conf->upstream.hide_headers = NGX_CONF_UNSET_PTR;
    conf->upstream.pass_headers = NGX_CONF_UNSET_PTR;

    conf->upstream.intercept_errors = NGX_CONF_UNSET;

    /* "proxy_cyclic_temp_file" is disabled */
    conf->upstream.cyclic_temp_file = 0;

    conf->redirect = NGX_CONF_UNSET;
    conf->upstream.change_buffering = 1;

    conf->headers_hash_max_size = NGX_CONF_UNSET_UINT;
    conf->headers_hash_bucket_size = NGX_CONF_UNSET_UINT;

    return conf;
}


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

    u_char                       *p;
    size_t                        size;
    uintptr_t                    *code;
    ngx_uint_t                    i;
    ngx_keyval_t                 *src, *s, *h;
    ngx_hash_key_t               *hk;
    ngx_hash_init_t               hash;
    ngx_http_proxy_redirect_t    *pr;
    ngx_http_script_compile_t     sc;
    ngx_http_script_copy_code_t  *copy;

    if (conf->upstream.store != 0) {
        ngx_conf_merge_value(conf->upstream.store,
                                  prev->upstream.store, 0);

        if (conf->upstream.store_lengths == NULL) {
            conf->upstream.store_lengths = prev->upstream.store_lengths;
            conf->upstream.store_values = prev->upstream.store_values;
        }
    }

    ngx_conf_merge_uint_value(conf->upstream.store_access,
                              prev->upstream.store_access, 0600);

    ngx_conf_merge_value(conf->upstream.buffering,
                              prev->upstream.buffering, 1);

    ngx_conf_merge_value(conf->upstream.ignore_client_abort,
                              prev->upstream.ignore_client_abort, 0);

    ngx_conf_merge_msec_value(conf->upstream.connect_timeout,
                              prev->upstream.connect_timeout, 60000);

    ngx_conf_merge_msec_value(conf->upstream.send_timeout,
                              prev->upstream.send_timeout, 60000);

    ngx_conf_merge_msec_value(conf->upstream.read_timeout,
                              prev->upstream.read_timeout, 60000);

    ngx_conf_merge_size_value(conf->upstream.send_lowat,
                              prev->upstream.send_lowat, 0);

    ngx_conf_merge_size_value(conf->upstream.buffer_size,
                              prev->upstream.buffer_size,
                              (size_t) ngx_pagesize);

    ngx_conf_merge_bufs_value(conf->upstream.bufs, prev->upstream.bufs,
                              8, ngx_pagesize);

    if (conf->upstream.bufs.num < 2) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "there must be at least 2 \"proxy_buffers\"");
        return NGX_CONF_ERROR;
    }


    size = conf->upstream.buffer_size;
    if (size < conf->upstream.bufs.size) {
        size = conf->upstream.bufs.size;
    }


    ngx_conf_merge_size_value(conf->upstream.busy_buffers_size_conf,
                              prev->upstream.busy_buffers_size_conf,
                              NGX_CONF_UNSET_SIZE);

    if (conf->upstream.busy_buffers_size_conf == NGX_CONF_UNSET_SIZE) {
        conf->upstream.busy_buffers_size = 2 * size;
    } else {
        conf->upstream.busy_buffers_size =
                                         conf->upstream.busy_buffers_size_conf;
    }

    if (conf->upstream.busy_buffers_size < size) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
             "\"proxy_busy_buffers_size\" must be equal or bigger than "
             "maximum of the value of \"proxy_buffer_size\" and "
             "one of the \"proxy_buffers\"");

        return NGX_CONF_ERROR;
    }

    if (conf->upstream.busy_buffers_size
        > (conf->upstream.bufs.num - 1) * conf->upstream.bufs.size)
    {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
             "\"proxy_busy_buffers_size\" must be less than "
             "the size of all \"proxy_buffers\" minus one buffer");

        return NGX_CONF_ERROR;
    }


    ngx_conf_merge_size_value(conf->upstream.temp_file_write_size_conf,
                              prev->upstream.temp_file_write_size_conf,
                              NGX_CONF_UNSET_SIZE);

    if (conf->upstream.temp_file_write_size_conf == NGX_CONF_UNSET_SIZE) {
        conf->upstream.temp_file_write_size = 2 * size;
    } else {
        conf->upstream.temp_file_write_size =
                                      conf->upstream.temp_file_write_size_conf;
    }

    if (conf->upstream.temp_file_write_size < size) {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
             "\"proxy_temp_file_write_size\" must be equal or bigger than "
             "maximum of the value of \"proxy_buffer_size\" and "
             "one of the \"proxy_buffers\"");

        return NGX_CONF_ERROR;
    }

    ngx_conf_merge_size_value(conf->upstream.max_temp_file_size_conf,
                              prev->upstream.max_temp_file_size_conf,
                              NGX_CONF_UNSET_SIZE);

    if (conf->upstream.max_temp_file_size_conf == NGX_CONF_UNSET_SIZE) {
        conf->upstream.max_temp_file_size = 1024 * 1024 * 1024;
    } else {
        conf->upstream.max_temp_file_size =
                                        conf->upstream.max_temp_file_size_conf;
    }

    if (conf->upstream.max_temp_file_size != 0
        && conf->upstream.max_temp_file_size < size)
    {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
             "\"proxy_max_temp_file_size\" must be equal to zero to disable "
             "the temporary files usage or must be equal or bigger than "
             "maximum of the value of \"proxy_buffer_size\" and "
             "one of the \"proxy_buffers\"");

        return NGX_CONF_ERROR;
    }


    ngx_conf_merge_bitmask_value(conf->upstream.next_upstream,
                              prev->upstream.next_upstream,
                              (NGX_CONF_BITMASK_SET
                               |NGX_HTTP_UPSTREAM_FT_ERROR
                               |NGX_HTTP_UPSTREAM_FT_TIMEOUT));