ngx_http_rewrite_module.c

nginx 反向代理0.7.1版本 用于实现反向代理

}


static char *
ngx_http_rewrite_if(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_rewrite_loc_conf_t  *lcf = conf;

    void                         *mconf;
    char                         *rv;
    u_char                       *elts;
    ngx_uint_t                    i;
    ngx_conf_t                    save;
    ngx_http_module_t            *module;
    ngx_http_conf_ctx_t          *ctx, *pctx;
    ngx_http_core_loc_conf_t     *clcf, *pclcf;
    ngx_http_script_if_code_t    *if_code;
    ngx_http_rewrite_loc_conf_t  *nlcf;

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

    pctx = cf->ctx;
    ctx->main_conf = pctx->main_conf;
    ctx->srv_conf = pctx->srv_conf;

    ctx->loc_conf = ngx_pcalloc(cf->pool, sizeof(void *) * ngx_http_max_module);
    if (ctx->loc_conf == NULL) {
        return NGX_CONF_ERROR;
    }

    for (i = 0; ngx_modules[i]; i++) {
        if (ngx_modules[i]->type != NGX_HTTP_MODULE) {
            continue;
        }

        module = ngx_modules[i]->ctx;

        if (module->create_loc_conf) {

            mconf = module->create_loc_conf(cf);
            if (mconf == NULL) {
                 return NGX_CONF_ERROR;
            }

            ctx->loc_conf[ngx_modules[i]->ctx_index] = mconf;
        }
    }

    pclcf = pctx->loc_conf[ngx_http_core_module.ctx_index];

    clcf = ctx->loc_conf[ngx_http_core_module.ctx_index];
    clcf->loc_conf = ctx->loc_conf;
    clcf->name = pclcf->name;
    clcf->noname = 1;

    if (ngx_http_add_location(cf, &pclcf->locations, clcf) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    if (ngx_http_rewrite_if_condition(cf, lcf) != NGX_CONF_OK) {
        return NGX_CONF_ERROR;
    }

    if_code = ngx_array_push_n(lcf->codes, sizeof(ngx_http_script_if_code_t));
    if (if_code == NULL) {
        return NULL;
    }

    if_code->code = ngx_http_script_if_code;

    elts = lcf->codes->elts;


    /* the inner directives must be compiled to the same code array */

    nlcf = ctx->loc_conf[ngx_http_rewrite_module.ctx_index];
    nlcf->codes = lcf->codes;


    save = *cf;
    cf->ctx = ctx;

    if (pclcf->name.len == 0) {
        if_code->loc_conf = NULL;
        cf->cmd_type = NGX_HTTP_SIF_CONF;

    } else {
        if_code->loc_conf = ctx->loc_conf;
        cf->cmd_type = NGX_HTTP_LIF_CONF;
    }

    rv = ngx_conf_parse(cf, NULL);

    *cf = save;

    if (rv != NGX_CONF_OK) {
        return rv;
    }


    if (lcf->captures < nlcf->captures) {
        lcf->captures = nlcf->captures;
    }


    if (elts != lcf->codes->elts) {
        if_code = (ngx_http_script_if_code_t *)
                   ((u_char *) if_code + ((u_char *) lcf->codes->elts - elts));
    }

    if_code->next = (u_char *) lcf->codes->elts + lcf->codes->nelts
                                                - (u_char *) if_code;

    /* the code array belong to parent block */

    nlcf->codes = NULL;

    return NGX_CONF_OK;
}


static char *
ngx_http_rewrite_if_condition(ngx_conf_t *cf, ngx_http_rewrite_loc_conf_t *lcf)
{
    u_char                        *p;
    size_t                         len;
    ngx_str_t                     *value, err;
    ngx_uint_t                     cur, last, n;
    ngx_http_script_code_pt       *code;
    ngx_http_script_file_code_t   *fop;
    ngx_http_script_regex_code_t  *regex;
    u_char                         errstr[NGX_MAX_CONF_ERRSTR];

    value = cf->args->elts;
    last = cf->args->nelts - 1;

    if (value[1].len < 1 || value[1].data[0] != '(') {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid condition \"%V\"", &value[1]);
        return NGX_CONF_ERROR;
    }

    if (value[1].len == 1) {
        cur = 2;

    } else {
        cur = 1;
        value[1].len--;
        value[1].data++;
    }

    if (value[last].len < 1 || value[last].data[value[last].len - 1] != ')') {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid condition \"%V\"", &value[last]);
        return NGX_CONF_ERROR;
    }

    if (value[last].len == 1) {
        last--;

    } else {
        value[last].len--;
        value[last].data[value[last].len] = '\0';
    }

    len = value[cur].len;
    p = value[cur].data;

    if (len > 1 && p[0] == '$') {

        if (cur != last && cur + 2 != last) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "invalid condition \"%V\"", &value[cur]);
            return NGX_CONF_ERROR;
        }

        if (ngx_http_rewrite_variable(cf, lcf, &value[cur]) != NGX_CONF_OK) {
            return NGX_CONF_ERROR;
        }

        if (cur == last) {
            return NGX_CONF_OK;
        }

        cur++;

        len = value[cur].len;
        p = value[cur].data;

        if (len == 1 && p[0] == '=') {

            if (ngx_http_rewrite_value(cf, lcf, &value[last]) != NGX_CONF_OK) {
                return NGX_CONF_ERROR;
            }

            code = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                              sizeof(uintptr_t));
            if (code == NULL) {
                return NGX_CONF_ERROR;
            }

            *code = ngx_http_script_equal_code;

            return NGX_CONF_OK;
        }

        if (len == 2 && p[0] == '!' && p[1] == '=') {

            if (ngx_http_rewrite_value(cf, lcf, &value[last]) != NGX_CONF_OK) {
                return NGX_CONF_ERROR;
            }

            code = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                              sizeof(uintptr_t));
            if (code == NULL) {
                return NGX_CONF_ERROR;
            }

            *code = ngx_http_script_not_equal_code;
            return NGX_CONF_OK;
        }

        if ((len == 1 && p[0] == '~')
            || (len == 2 && p[0] == '~' && p[1] == '*')
            || (len == 2 && p[0] == '!' && p[1] == '~')
            || (len == 3 && p[0] == '!' && p[1] == '~' && p[2] == '*'))
        {
            regex = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                         sizeof(ngx_http_script_regex_code_t));
            if (regex == NULL) {
                return NGX_CONF_ERROR;
            }

            ngx_memzero(regex, sizeof(ngx_http_script_regex_code_t));

            err.len = NGX_MAX_CONF_ERRSTR;
            err.data = errstr;

            regex->regex = ngx_regex_compile(&value[last],
                                  (p[len - 1] == '*') ? NGX_REGEX_CASELESS : 0,
                                   cf->pool, &err);

            if (regex->regex == NULL) {
                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "%s", err.data);
                return NGX_CONF_ERROR;
            }

            regex->code = ngx_http_script_regex_start_code;
            regex->next = sizeof(ngx_http_script_regex_code_t);
            regex->test = 1;
            if (p[0] == '!') {
                regex->negative_test = 1;
            }
            regex->name = value[last];

            n = ngx_regex_capture_count(regex->regex);

            if (n) {
                regex->ncaptures = (n + 1) * 3;

                if (lcf->captures < regex->ncaptures) {
                    lcf->captures = regex->ncaptures;
                }
            }

            return NGX_CONF_OK;
        }

        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "unexpected \"%V\" in condition", &value[cur]);
        return NGX_CONF_ERROR;

    } else if ((len == 2 && p[0] == '-')
               || (len == 3 && p[0] == '!' && p[1] == '-'))
    {
        if (cur + 1 != last) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "invalid condition \"%V\"", &value[cur]);
            return NGX_CONF_ERROR;
        }

        value[last].data[value[last].len] = '\0';
        value[last].len++;

        if (ngx_http_rewrite_value(cf, lcf, &value[last]) != NGX_CONF_OK) {
            return NGX_CONF_ERROR;
        }

        fop = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                          sizeof(ngx_http_script_file_code_t));
        if (fop == NULL) {
            return NGX_CONF_ERROR;
        }

        fop->code = ngx_http_script_file_code;

        if (p[1] == 'f') {
            fop->op = ngx_http_script_file_plain;
            return NGX_CONF_OK;
        }

        if (p[1] == 'd') {
            fop->op = ngx_http_script_file_dir;
            return NGX_CONF_OK;
        }

        if (p[1] == 'e') {
            fop->op = ngx_http_script_file_exists;
            return NGX_CONF_OK;
        }

        if (p[1] == 'x') {
            fop->op = ngx_http_script_file_exec;
            return NGX_CONF_OK;
        }

        if (p[0] == '!') {
            if (p[2] == 'f') {
                fop->op = ngx_http_script_file_not_plain;
                return NGX_CONF_OK;
            }

            if (p[2] == 'd') {
                fop->op = ngx_http_script_file_not_dir;
                return NGX_CONF_OK;
            }

            if (p[2] == 'e') {
                fop->op = ngx_http_script_file_not_exists;
                return NGX_CONF_OK;
            }

            if (p[2] == 'x') {
                fop->op = ngx_http_script_file_not_exec;
                return NGX_CONF_OK;
            }
        }

        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid condition \"%V\"", &value[cur]);
        return NGX_CONF_ERROR;
    }

    ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                       "invalid condition \"%V\"", &value[cur]);

    return NGX_CONF_ERROR;
}


static char *
ngx_http_rewrite_variable(ngx_conf_t *cf, ngx_http_rewrite_loc_conf_t *lcf,
    ngx_str_t *value)
{
    ngx_int_t                    index;
    ngx_http_script_var_code_t  *var_code;

    value->len--;
    value->data++;

    index = ngx_http_get_variable_index(cf, value);

    if (index == NGX_ERROR) {
        return NGX_CONF_ERROR;
    }

    var_code = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                          sizeof(ngx_http_script_var_code_t));
    if (var_code == NULL) {
        return NGX_CONF_ERROR;
    }

    var_code->code = ngx_http_script_var_code;
    var_code->index = index;

    return NGX_CONF_OK;
}


static char *
ngx_http_rewrite_set(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_rewrite_loc_conf_t  *lcf = conf;

    ngx_int_t                            index;
    ngx_str_t                           *value;
    ngx_http_variable_t                 *v;
    ngx_http_script_var_code_t          *vcode;
    ngx_http_script_var_handler_code_t  *vhcode;

    value = cf->args->elts;

    if (value[1].data[0] != '$') {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "invalid variable name \"%V\"", &value[1]);
        return NGX_CONF_ERROR;
    }

    value[1].len--;
    value[1].data++;

    v = ngx_http_add_variable(cf, &value[1], NGX_HTTP_VAR_CHANGEABLE);
    if (v == NULL) {
        return NGX_CONF_ERROR;
    }

    index = ngx_http_get_variable_index(cf, &value[1]);
    if (index == NGX_ERROR) {
        return NGX_CONF_ERROR;
    }

    if (v->get_handler == NULL
        && ngx_strncasecmp(value[1].data, (u_char *) "http_", 5) != 0
        && ngx_strncasecmp(value[1].data, (u_char *) "sent_http_", 10) != 0
        && ngx_strncasecmp(value[1].data, (u_char *) "upstream_http_", 14) != 0)
    {
        v->get_handler = ngx_http_rewrite_var;
        v->data = index;
    }

    if (ngx_http_rewrite_value(cf, lcf, &value[2]) != NGX_CONF_OK) {
        return NGX_CONF_ERROR;
    }

    if (v->set_handler) {
        vhcode = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                   sizeof(ngx_http_script_var_handler_code_t));
        if (vhcode == NULL) {
            return NGX_CONF_ERROR;
        }

        vhcode->code = ngx_http_script_var_set_handler_code;
        vhcode->handler = v->set_handler;
        vhcode->data = v->data;

        return NGX_CONF_OK;
    }

    vcode = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                       sizeof(ngx_http_script_var_code_t));
    if (vcode == NULL) {
        return NGX_CONF_ERROR;
    }

    vcode->code = ngx_http_script_set_var_code;
    vcode->index = (uintptr_t) index;

    return NGX_CONF_OK;
}


static char *
ngx_http_rewrite_value(ngx_conf_t *cf, ngx_http_rewrite_loc_conf_t *lcf,
    ngx_str_t *value)
{
    ngx_int_t                              n;
    ngx_http_script_compile_t              sc;
    ngx_http_script_value_code_t          *val;
    ngx_http_script_complex_value_code_t  *complex;

    n = ngx_http_script_variables_count(value);

    if (n == 0) {
        val = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                         sizeof(ngx_http_script_value_code_t));
        if (val == NULL) {
            return NGX_CONF_ERROR;
        }

        n = ngx_atoi(value->data, value->len);

        if (n == NGX_ERROR) {
            n = 0;
        }

        val->code = ngx_http_script_value_code;
        val->value = (uintptr_t) n;
        val->text_len = (uintptr_t) value->len;
        val->text_data = (uintptr_t) value->data;

        return NGX_CONF_OK;
    }

    complex = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                 sizeof(ngx_http_script_complex_value_code_t));
    if (complex == NULL) {
        return NGX_CONF_ERROR;
    }

    complex->code = ngx_http_script_complex_value_code;
    complex->lengths = NULL;

    ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));

    sc.cf = cf;
    sc.source = value;
    sc.lengths = &complex->lengths;
    sc.values = &lcf->codes;
    sc.variables = n;
    sc.complete_lengths = 1;

    if (ngx_http_script_compile(&sc) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}