diff options
Diffstat (limited to 'src/http/modules/ngx_http_referer_module.c')
| -rw-r--r-- | src/http/modules/ngx_http_referer_module.c | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/src/http/modules/ngx_http_referer_module.c b/src/http/modules/ngx_http_referer_module.c new file mode 100644 index 000000000..a3d3d4606 --- /dev/null +++ b/src/http/modules/ngx_http_referer_module.c @@ -0,0 +1,309 @@ + +/* + * Copyright (C) Igor Sysoev + */ + + +#include <ngx_config.h> +#include <ngx_core.h> +#include <ngx_http.h> + + +typedef struct { + ngx_str_t name; + ngx_uint_t wildcard; +} ngx_http_referer_t; + +typedef struct { + ngx_array_t *referers; /* ngx_http_referer_t */ + + ngx_flag_t no_referer; + ngx_flag_t blocked_referer; +} ngx_http_referer_conf_t; + + +static void * ngx_http_referer_create_conf(ngx_conf_t *cf); +static char * ngx_http_referer_merge_conf(ngx_conf_t *cf, void *parent, + void *child); +static char *ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd, + void *conf); + + +static ngx_command_t ngx_http_referer_commands[] = { + + { ngx_string("valid_referers"), + NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_1MORE, + ngx_http_valid_referers, + NGX_HTTP_LOC_CONF_OFFSET, + 0, + NULL }, + + ngx_null_command +}; + + +static ngx_http_module_t ngx_http_referer_module_ctx = { + NULL, /* preconfiguration */ + NULL, /* postconfiguration */ + + NULL, /* create main configuration */ + NULL, /* init main configuration */ + + NULL, /* create server configuration */ + NULL, /* merge server configuration */ + + ngx_http_referer_create_conf, /* create location configuration */ + ngx_http_referer_merge_conf /* merge location configuration */ +}; + + +ngx_module_t ngx_http_referer_module = { + NGX_MODULE_V1, + &ngx_http_referer_module_ctx, /* module context */ + ngx_http_referer_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_int_t +ngx_http_referer_variable(ngx_http_request_t *r, ngx_http_variable_value_t *v, + uintptr_t data) +{ + u_char *ref; + size_t len; + ngx_uint_t i, n; + ngx_http_referer_t *refs; + ngx_http_referer_conf_t *cf; + + cf = ngx_http_get_module_loc_conf(r, ngx_http_referer_module); + + if (cf->referers == NULL) { + *v = ngx_http_variable_null_value; + return NGX_OK; + } + + if (r->headers_in.referer == NULL) { + if (cf->no_referer) { + *v = ngx_http_variable_null_value; + return NGX_OK; + + } else { + *v = ngx_http_variable_true_value; + return NGX_OK; + } + } + + len = r->headers_in.referer->value.len; + ref = r->headers_in.referer->value.data; + + if (len < sizeof("http://i.ru") - 1 + || (ngx_strncasecmp(ref, "http://", 7) != 0)) + { + if (cf->blocked_referer) { + *v = ngx_http_variable_null_value; + return NGX_OK; + + } else { + *v = ngx_http_variable_true_value; + return NGX_OK; + } + } + + len -= 7; + ref += 7; + + refs = cf->referers->elts; + for (i = 0; i < cf->referers->nelts; i++ ){ + + if (refs[i].name.len > len) { + continue; + } + + if (refs[i].wildcard) { + for (n = 0; n < len; n++) { + if (ref[n] == '/' || ref[n] == ':') { + break; + } + + if (ref[n] != '.') { + continue; + } + + if (ngx_strncmp(&ref[n], refs[i].name.data, + refs[i].name.len) == 0) + { + *v = ngx_http_variable_null_value; + return NGX_OK; + } + } + + } else { + if (ngx_strncasecmp(refs[i].name.data, ref, refs[i].name.len) == 0) + { + *v = ngx_http_variable_null_value; + return NGX_OK; + } + } + } + + *v = ngx_http_variable_true_value; + + return NGX_OK; +} + + +static void * +ngx_http_referer_create_conf(ngx_conf_t *cf) +{ + ngx_http_referer_conf_t *conf; + + conf = ngx_palloc(cf->pool, sizeof(ngx_http_referer_conf_t)); + if (conf == NULL) { + return NGX_CONF_ERROR; + } + + conf->referers = NULL; + conf->no_referer = NGX_CONF_UNSET; + conf->blocked_referer = NGX_CONF_UNSET; + + return conf; +} + + +static char * +ngx_http_referer_merge_conf(ngx_conf_t *cf, void *parent, void *child) +{ + ngx_http_referer_conf_t *prev = parent; + ngx_http_referer_conf_t *conf = child; + + if (conf->referers == NULL) { + conf->referers = prev->referers; + ngx_conf_merge_value(conf->no_referer, prev->no_referer, 0); + ngx_conf_merge_value(conf->blocked_referer, prev->blocked_referer, 0); + } + + if (conf->no_referer == NGX_CONF_UNSET) { + conf->no_referer = 0; + } + + if (conf->blocked_referer == NGX_CONF_UNSET) { + conf->blocked_referer = 0; + } + + return NGX_CONF_OK; +} + + +static char * +ngx_http_valid_referers(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) +{ + ngx_http_referer_conf_t *lcf = conf; + + ngx_uint_t i, server_names; + ngx_str_t *value, name; + ngx_http_referer_t *ref; + ngx_http_variable_t *var; + ngx_http_server_name_t *sn; + ngx_http_core_srv_conf_t *cscf; + + name.len = sizeof("invalid_referer") - 1; + name.data = (u_char *) "invalid_referer"; + + var = ngx_http_add_variable(cf, &name, NGX_HTTP_VAR_CHANGABLE); + if (var == NULL) { + return NGX_CONF_ERROR; + } + + var->handler = ngx_http_referer_variable; + + cscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_core_module); + + if (lcf->referers == NULL) { + lcf->referers = ngx_array_create(cf->pool, + cf->args->nelts + cscf->server_names.nelts, + sizeof(ngx_http_referer_t)); + if (lcf->referers == NULL) { + return NGX_CONF_ERROR; + } + } + + value = cf->args->elts; + server_names = 0; + + for (i = 1; i < cf->args->nelts; i++) { + if (value[i].len == 0) { + ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, + "invalid referer \"%V\"", &value[i]); + return NGX_CONF_ERROR; + } + + if (ngx_strcmp(value[i].data, "none") == 0) { + lcf->no_referer = 1; + continue; + } + + if (ngx_strcmp(value[i].data, "blocked") == 0) { + lcf->blocked_referer = 1; + continue; + } + + if (ngx_strcmp(value[i].data, "server_names") == 0) { + server_names = 1; + continue; + } + + ref = ngx_array_push(lcf->referers); + if (ref == NULL) { + return NGX_CONF_ERROR; + } + + if (value[i].data[0] != '*') { + ref->name = value[i]; + ref->wildcard = 0; + continue; + } + + + if (value[i].data[1] != '.') { + ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, + "invalid wildcard referer \"%V\"", &value[i]); + return NGX_CONF_ERROR; + } + + ref->name.len = value[i].len - 1; + ref->name.data = value[i].data + 1; + ref->wildcard = 1; + } + + if (!server_names) { + return NGX_CONF_OK; + } + + sn = cscf->server_names.elts; + for (i = 0; i < cscf->server_names.nelts; i++) { + ref = ngx_array_push(lcf->referers); + if (ref == NULL) { + return NGX_CONF_ERROR; + } + + ref->name.len = sn[i].name.len + 1; + ref->name.data = ngx_palloc(cf->pool, ref->name.len); + if (ref->name.data == NULL) { + return NGX_CONF_ERROR; + } + + ngx_memcpy(ref->name.data, sn[i].name.data, sn[i].name.len); + ref->name.data[sn[i].name.len] = '/'; + ref->wildcard = sn[i].wildcard; + } + + return NGX_CONF_OK; +} |