/* Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /* * http_alias.c: Stuff for dealing with directory aliases * * Original by Rob McCool, rewritten in succession by David Robinson * and rst. * */ #include "apr_strings.h" #include "apr_lib.h" #define APR_WANT_STRFUNC #include "apr_want.h" #include "ap_config.h" #include "httpd.h" #include "http_core.h" #include "http_config.h" #include "http_request.h" #include "http_log.h" typedef struct { const char *real; const char *fake; char *handler; ap_regex_t *regexp; int redir_status; /* 301, 302, 303, 410, etc */ } alias_entry; typedef struct { apr_array_header_t *aliases; apr_array_header_t *redirects; } alias_server_conf; typedef struct { apr_array_header_t *redirects; } alias_dir_conf; module AP_MODULE_DECLARE_DATA alias_module; static void *create_alias_config(apr_pool_t *p, server_rec *s) { alias_server_conf *a = (alias_server_conf *) apr_pcalloc(p, sizeof(alias_server_conf)); a->aliases = apr_array_make(p, 20, sizeof(alias_entry)); a->redirects = apr_array_make(p, 20, sizeof(alias_entry)); return a; } static void *create_alias_dir_config(apr_pool_t *p, char *d) { alias_dir_conf *a = (alias_dir_conf *) apr_pcalloc(p, sizeof(alias_dir_conf)); a->redirects = apr_array_make(p, 2, sizeof(alias_entry)); return a; } static void *merge_alias_config(apr_pool_t *p, void *basev, void *overridesv) { alias_server_conf *a = (alias_server_conf *) apr_pcalloc(p, sizeof(alias_server_conf)); alias_server_conf *base = (alias_server_conf *) basev; alias_server_conf *overrides = (alias_server_conf *) overridesv; a->aliases = apr_array_append(p, overrides->aliases, base->aliases); a->redirects = apr_array_append(p, overrides->redirects, base->redirects); return a; } static void *merge_alias_dir_config(apr_pool_t *p, void *basev, void *overridesv) { alias_dir_conf *a = (alias_dir_conf *) apr_pcalloc(p, sizeof(alias_dir_conf)); alias_dir_conf *base = (alias_dir_conf *) basev; alias_dir_conf *overrides = (alias_dir_conf *) overridesv; a->redirects = apr_array_append(p, overrides->redirects, base->redirects); return a; } /* need prototype for overlap check */ static int alias_matches(const char *uri, const char *alias_fakename); static const char *add_alias_internal(cmd_parms *cmd, void *dummy, const char *f, const char *r, int use_regex) { server_rec *s = cmd->server; alias_server_conf *conf = ap_get_module_config(s->module_config, &alias_module); alias_entry *new = apr_array_push(conf->aliases); alias_entry *entries = (alias_entry *)conf->aliases->elts; int i; /* XX r can NOT be relative to DocumentRoot here... compat bug. */ if (use_regex) { new->regexp = ap_pregcomp(cmd->pool, f, AP_REG_EXTENDED); if (new->regexp == NULL) return "Regular expression could not be compiled."; new->real = r; } else { /* XXX This may be optimized, but we must know that new->real * exists. If so, we can dir merge later, trusing new->real * and just canonicalizing the remainder. Not till I finish * cleaning out the old ap_canonical stuff first. */ new->real = r; } new->fake = f; new->handler = cmd->info; /* check for overlapping (Script)Alias directives * and throw a warning if found one */ if (!use_regex) { for (i = 0; i < conf->aliases->nelts - 1; ++i) { alias_entry *p = &entries[i]; if ( (!p->regexp && alias_matches(f, p->fake) > 0) || (p->regexp && !ap_regexec(p->regexp, f, 0, NULL, 0))) { ap_log_error(APLOG_MARK, APLOG_WARNING, 0, cmd->server, "The %s directive in %s at line %d will probably " "never match because it overlaps an earlier " "%sAlias%s.", cmd->cmd->name, cmd->directive->filename, cmd->directive->line_num, p->handler ? "Script" : "", p->regexp ? "Match" : ""); break; /* one warning per alias should be sufficient */ } } } return NULL; } static const char *add_alias(cmd_parms *cmd, void *dummy, const char *f, const char *r) { return add_alias_internal(cmd, dummy, f, r, 0); } static const char *add_alias_regex(cmd_parms *cmd, void *dummy, const char *f, const char *r) { return add_alias_internal(cmd, dummy, f, r, 1); } static const char *add_redirect_internal(cmd_parms *cmd, alias_dir_conf *dirconf, const char *arg1, const char *arg2, const char *arg3, int use_regex) { alias_entry *new; server_rec *s = cmd->server; alias_server_conf *serverconf = ap_get_module_config(s->module_config, &alias_module); int status = (int) (long) cmd->info; ap_regex_t *r = NULL; const char *f = arg2; const char *url = arg3; if (!strcasecmp(arg1, "gone")) status = HTTP_GONE; else if (!strcasecmp(arg1, "permanent")) status = HTTP_MOVED_PERMANENTLY; else if (!strcasecmp(arg1, "temp")) status = HTTP_MOVED_TEMPORARILY; else if (!strcasecmp(arg1, "seeother")) status = HTTP_SEE_OTHER; else if (apr_isdigit(*arg1)) status = atoi(arg1); else { f = arg1; url = arg2; } if (use_regex) { r = ap_pregcomp(cmd->pool, f, AP_REG_EXTENDED); if (r == NULL) return "Regular expression could not be compiled."; } if (ap_is_HTTP_REDIRECT(status)) { if (!url) return "URL to redirect to is missing"; /* PR#35314: we can allow path components here; * they get correctly resolved to full URLs. */ if (!use_regex && !ap_is_url(url) && (url[0] != '/')) return "Redirect to non-URL"; } else { if (url) return "Redirect URL not valid for this status"; } if (cmd->path) new = apr_array_push(dirconf->redirects); else new = apr_array_push(serverconf->redirects); new->fake = f; new->real = url; new->regexp = r; new->redir_status = status; return NULL; } static const char *add_redirect(cmd_parms *cmd, void *dirconf, const char *arg1, const char *arg2, const char *arg3) { return add_redirect_internal(cmd, dirconf, arg1, arg2, arg3, 0); } static const char *add_redirect2(cmd_parms *cmd, void *dirconf, const char *arg1, const char *arg2) { return add_redirect_internal(cmd, dirconf, arg1, arg2, NULL, 0); } static const char *add_redirect_regex(cmd_parms *cmd, void *dirconf, const char *arg1, const char *arg2, const char *arg3) { return add_redirect_internal(cmd, dirconf, arg1, arg2, arg3, 1); } static const command_rec alias_cmds[] = { AP_INIT_TAKE2("Alias", add_alias, NULL, RSRC_CONF, "a fakename and a realname"), AP_INIT_TAKE2("ScriptAlias", add_alias, "cgi-script", RSRC_CONF, "a fakename and a realname"), AP_INIT_TAKE23("Redirect", add_redirect, (void *) HTTP_MOVED_TEMPORARILY, OR_FILEINFO, "an optional status, then document to be redirected and " "destination URL"), AP_INIT_TAKE2("AliasMatch", add_alias_regex, NULL, RSRC_CONF, "a regular expression and a filename"), AP_INIT_TAKE2("ScriptAliasMatch", add_alias_regex, "cgi-script", RSRC_CONF, "a regular expression and a filename"), AP_INIT_TAKE23("RedirectMatch", add_redirect_regex, (void *) HTTP_MOVED_TEMPORARILY, OR_FILEINFO, "an optional status, then a regular expression and " "destination URL"), AP_INIT_TAKE2("RedirectTemp", add_redirect2, (void *) HTTP_MOVED_TEMPORARILY, OR_FILEINFO, "a document to be redirected, then the destination URL"), AP_INIT_TAKE2("RedirectPermanent", add_redirect2, (void *) HTTP_MOVED_PERMANENTLY, OR_FILEINFO, "a document to be redirected, then the destination URL"), {NULL} }; static int alias_matches(const char *uri, const char *alias_fakename) { const char *aliasp = alias_fakename, *urip = uri; while (*aliasp) { if (*aliasp == '/') { /* any number of '/' in the alias matches any number in * the supplied URI, but there must be at least one... */ if (*urip != '/') return 0; do { ++aliasp; } while (*aliasp == '/'); do { ++urip; } while (*urip == '/'); } else { /* Other characters are compared literally */ if (*urip++ != *aliasp++) return 0; } } /* Check last alias path component matched all the way */ if (aliasp[-1] != '/' && *urip != '\0' && *urip != '/') return 0; /* Return number of characters from URI which matched (may be * greater than length of alias, since we may have matched * doubled slashes) */ return urip - uri; } static char *try_alias_list(request_rec *r, apr_array_header_t *aliases, int doesc, int *status) { alias_entry *entries = (alias_entry *) aliases->elts; ap_regmatch_t regm[AP_MAX_REG_MATCH]; char *found = NULL; int i; for (i = 0; i < aliases->nelts; ++i) { alias_entry *p = &entries[i]; int l; if (p->regexp) { if (!ap_regexec(p->regexp, r->uri, AP_MAX_REG_MATCH, regm, 0)) { if (p->real) { found = ap_pregsub(r->pool, p->real, r->uri, AP_MAX_REG_MATCH, regm); if (found && doesc) { apr_uri_t uri; apr_uri_parse(r->pool, found, &uri); /* Do not escape the query string or fragment. */ found = apr_uri_unparse(r->pool, &uri, APR_URI_UNP_OMITQUERY); found = ap_escape_uri(r->pool, found); if (uri.query) { found = apr_pstrcat(r->pool, found, "?", uri.query, NULL); } if (uri.fragment) { found = apr_pstrcat(r->pool, found, "#", uri.fragment, NULL); } } } else { /* need something non-null */ found = apr_pstrdup(r->pool, ""); } } } else { l = alias_matches(r->uri, p->fake); if (l > 0) { if (doesc) { char *escurl; escurl = ap_os_escape_path(r->pool, r->uri + l, 1); found = apr_pstrcat(r->pool, p->real, escurl, NULL); } else found = apr_pstrcat(r->pool, p->real, r->uri + l, NULL); } } if (found) { if (p->handler) { /* Set handler, and leave a note for mod_cgi */ r->handler = p->handler; apr_table_setn(r->notes, "alias-forced-type", r->handler); } /* XXX This is as SLOW as can be, next step, we optimize * and merge to whatever part of the found path was already * canonicalized. After I finish eliminating os canonical. * Better fail test for ap_server_root_relative needed here. */ if (!doesc) { found = ap_server_root_relative(r->pool, found); } if (found) { *status = p->redir_status; } return found; } } return NULL; } static int translate_alias_redir(request_rec *r) { ap_conf_vector_t *sconf = r->server->module_config; alias_server_conf *serverconf = ap_get_module_config(sconf, &alias_module); char *ret; int status; if (r->uri[0] != '/' && r->uri[0] != '\0') { return DECLINED; } if ((ret = try_alias_list(r, serverconf->redirects, 1, &status)) != NULL) { if (ap_is_HTTP_REDIRECT(status)) { /* include QUERY_STRING if any */ if (r->args) { ret = apr_pstrcat(r->pool, ret, "?", r->args, NULL); } apr_table_setn(r->headers_out, "Location", ret); } return status; } if ((ret = try_alias_list(r, serverconf->aliases, 0, &status)) != NULL) { r->filename = ret; return OK; } return DECLINED; } static int fixup_redir(request_rec *r) { void *dconf = r->per_dir_config; alias_dir_conf *dirconf = (alias_dir_conf *) ap_get_module_config(dconf, &alias_module); char *ret; int status; /* It may have changed since last time, so try again */ if ((ret = try_alias_list(r, dirconf->redirects, 1, &status)) != NULL) { if (ap_is_HTTP_REDIRECT(status)) { if (ret[0] == '/') { char *orig_target = ret; ret = ap_construct_url(r->pool, ret, r); ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, "incomplete redirection target of '%s' for " "URI '%s' modified to '%s'", orig_target, r->uri, ret); } if (!ap_is_url(ret)) { status = HTTP_INTERNAL_SERVER_ERROR; ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, "cannot redirect '%s' to '%s'; " "target is not a valid absoluteURI or abs_path", r->uri, ret); } else { /* append requested query only, if the config didn't * supply its own. */ if (r->args && !ap_strchr(ret, '?')) { ret = apr_pstrcat(r->pool, ret, "?", r->args, NULL); } apr_table_setn(r->headers_out, "Location", ret); } } return status; } return DECLINED; } static void register_hooks(apr_pool_t *p) { static const char * const aszSucc[]={ "mod_userdir.c", "mod_vhost_alias.c",NULL }; ap_hook_translate_name(translate_alias_redir,NULL,aszSucc,APR_HOOK_MIDDLE); ap_hook_fixups(fixup_redir,NULL,NULL,APR_HOOK_MIDDLE); } module AP_MODULE_DECLARE_DATA alias_module = { STANDARD20_MODULE_STUFF, create_alias_dir_config, /* dir config creater */ merge_alias_dir_config, /* dir merger --- default is to override */ create_alias_config, /* server config */ merge_alias_config, /* merge server configs */ alias_cmds, /* command apr_table_t */ register_hooks /* register hooks */ };
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