Apache: The Definitive Guide, 3rd Edition

Name

Check Access

Synopsis

int module_check_access(request_rec *pReq)

This routine checks access, in the allow/deny sense. It can return OK , DECLINED, or a status code. All modules are called until one of them returns something other than DECLINED or OK. If all modules return DECLINED, it is considered a configuration error. At this point, the URL and the filename (if relevant) are known, as are the client’s address, user agent, and so forth. All of these are available through pReq. As long as everything says DECLINED or OK, the request can proceed.

The only example available in the standard modules is, unsurprisingly, from mod_access.c. See Example 21-17 for an excerpt from mod_access.c.

Example

Example 21-17. mod_access.c

static int find_allowdeny(request_rec *r, array_header *a, int method) { allowdeny *ap = (allowdeny *) a->elts; int mmask = (1 << method); int i; int gothost = 0; const char *remotehost = NULL; for (i = 0; i < a->nelts; ++i) { if (!(mmask & ap[i].limited)) continue; switch (ap[i].type) { case T_ENV: if (ap_table_get(r->subprocess_env, ap[i].x.from)) { return 1; } break; case T_ALL: return 1; case T_IP: if (ap[i].x.ip.net != INADDR_NONE && (r->connection->remote_addr.sin_addr.s_addr & ap[i].x.ip.mask) == ap[i].x.ip.net) { return 1; } break; case T_HOST: if (!gothost) { remotehost = ap_get_remote_host(r->connection, r->per_dir_config, REMOTE_DOUBLE_REV); if ((remotehost == NULL) || is_ip(remotehost)) gothost = 1; else gothost = 2; } if ((gothost == 2) && in_domain(ap[i].x.from, ...