diff options
Diffstat (limited to 'modules/mappers/mod_alias.c')
| -rw-r--r-- | modules/mappers/mod_alias.c | 727 |
1 files changed, 727 insertions, 0 deletions
diff --git a/modules/mappers/mod_alias.c b/modules/mappers/mod_alias.c new file mode 100644 index 0000000..5ff937b --- /dev/null +++ b/modules/mappers/mod_alias.c @@ -0,0 +1,727 @@ +/* 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" +#include "ap_expr.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 { + unsigned int alias_set:1; + unsigned int redirect_set:1; + apr_array_header_t *redirects; + const ap_expr_info_t *alias; + char *handler; + const ap_expr_info_t *redirect; + int redirect_status; /* 301, 302, 303, 410, etc */ +} alias_dir_conf; + +module AP_MODULE_DECLARE_DATA alias_module; + +static char magic_error_value; +#define PREGSUB_ERROR (&magic_error_value) + +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); + + a->alias = (overrides->alias_set == 0) ? base->alias : overrides->alias; + a->handler = (overrides->alias_set == 0) ? base->handler : overrides->handler; + a->alias_set = overrides->alias_set || base->alias_set; + + a->redirect = (overrides->redirect_set == 0) ? base->redirect : overrides->redirect; + a->redirect_status = (overrides->redirect_set == 0) ? base->redirect_status : overrides->redirect_status; + a->redirect_set = overrides->redirect_set || base->redirect_set; + + 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 *fake, const char *real, + 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; + + /* XXX: real can NOT be relative to DocumentRoot here... compat bug. */ + + const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT); + + if (err != NULL) { + return err; + } + + if (use_regex) { + new->regexp = ap_pregcomp(cmd->pool, fake, AP_REG_EXTENDED); + if (new->regexp == NULL) + return "Regular expression could not be compiled."; + new->real = real; + } + 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 = real; + } + new->fake = fake; + 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 *alias = &entries[i]; + + if ( (!alias->regexp && alias_matches(fake, alias->fake) > 0) + || (alias->regexp && !ap_regexec(alias->regexp, fake, 0, NULL, 0))) { + ap_log_error(APLOG_MARK, APLOG_WARNING, 0, cmd->server, APLOGNO(00671) + "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, + alias->handler ? "Script" : "", + alias->regexp ? "Match" : ""); + + break; /* one warning per alias should be sufficient */ + } + } + } + + return NULL; +} + +static const char *add_alias(cmd_parms *cmd, void *dummy, const char *fake, + const char *real) +{ + if (real) { + + return add_alias_internal(cmd, dummy, fake, real, 0); + + } + else { + alias_dir_conf *dirconf = (alias_dir_conf *) dummy; + + const char *err = ap_check_cmd_context(cmd, NOT_IN_DIRECTORY|NOT_IN_FILES); + + if (err != NULL) { + return err; + } + + if (!cmd->path) { + return "Alias must have two arguments when used globally"; + } + + dirconf->alias = + ap_expr_parse_cmd(cmd, fake, AP_EXPR_FLAG_STRING_RESULT, + &err, NULL); + if (err) { + return apr_pstrcat(cmd->temp_pool, + "Cannot parse alias expression '", fake, "': ", err, + NULL); + } + + dirconf->handler = cmd->info; + dirconf->alias_set = 1; + + return NULL; + + } +} + +static const char *add_alias_regex(cmd_parms *cmd, void *dummy, + const char *fake, const char *real) +{ + return add_alias_internal(cmd, dummy, fake, real, 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; + int grokarg1 = 1; + ap_regex_t *regex = NULL; + const char *fake = arg2; + const char *url = arg3; + + /* + * Logic flow: + * Go ahead and try to grok the 1st arg, in case it is a + * Redirect status. Now if we have 3 args, we expect that + * we were able to understand that 1st argument (it's something + * we expected, so if not, then we bail + */ + 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 (!strcasecmp(arg1, "gone")) { + status = HTTP_GONE; + grokarg1 = -1; + } + else if (apr_isdigit(*arg1)) { + status = atoi(arg1); + if (!ap_is_HTTP_REDIRECT(status)) { + grokarg1 = -1; + } + } + else { + grokarg1 = 0; + } + + if (arg3 && !grokarg1) + return "Redirect: invalid first argument (of three)"; + + /* + * if we have the 2nd arg and we understand the 1st one as a redirect + * status (3xx, but not things like 404 /robots.txt), or if we have the + * 1st arg but don't understand it, we use the expression syntax assuming + * a path from the location. + * + * if we understand the first arg but have no second arg, we are dealing + * with a status like "GONE" or a non-redirect status (e.g. 404, 503). + */ + if (!cmd->path) { + /* <Location> context only for now */ + ; + } + else if ((grokarg1 > 0 && arg2 && !arg3) || (!grokarg1 && !arg2)) { + const char *expr_err = NULL; + + url = grokarg1 ? arg2 : arg1; + dirconf->redirect = + ap_expr_parse_cmd(cmd, url, AP_EXPR_FLAG_STRING_RESULT, + &expr_err, NULL); + if (expr_err) { + return apr_pstrcat(cmd->temp_pool, + "Cannot parse redirect expression '", url, "': ", expr_err, + NULL); + } + + dirconf->redirect_status = status; + dirconf->redirect_set = 1; + + return NULL; + + } + else if (grokarg1 < 0 && !arg2) { + + dirconf->redirect_status = status; + dirconf->redirect_set = 1; + + return NULL; + + } + + /* + * if we don't have the 3rd arg and we didn't understand the 1st + * one, then assume URL-path URL. This also handles case, eg, GONE + * we even though we don't have a 3rd arg, we did understand the 1st + * one, so we don't want to re-arrange + */ + if (!arg3 && !grokarg1) { + fake = arg1; + url = arg2; + } + + if (use_regex) { + regex = ap_pregcomp(cmd->pool, fake, AP_REG_EXTENDED); + if (regex == 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 = fake; + new->real = url; + new->regexp = regex; + 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 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(request_rec *r) +{ + alias_dir_conf *dirconf = + (alias_dir_conf *) ap_get_module_config(r->per_dir_config, &alias_module); + + if (dirconf->alias) { + const char *err = NULL; + + char *found = apr_pstrdup(r->pool, + ap_expr_str_exec(r, dirconf->alias, &err)); + if (err) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02825) + "Can't evaluate alias expression: %s", err); + return PREGSUB_ERROR; + } + + if (dirconf->handler) { /* Set handler, and leave a note for mod_cgi */ + r->handler = dirconf->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. + */ + found = ap_server_root_relative(r->pool, found); + return found; + + } + + return NULL; +} + +static char *try_redirect(request_rec *r, int *status) +{ + alias_dir_conf *dirconf = + (alias_dir_conf *) ap_get_module_config(r->per_dir_config, &alias_module); + + if (dirconf->redirect_set) { + apr_uri_t uri; + const char *err = NULL; + char *found = ""; + + if (dirconf->redirect) { + + found = apr_pstrdup(r->pool, + ap_expr_str_exec(r, dirconf->redirect, &err)); + if (err) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02826) + "Can't evaluate redirect expression: %s", err); + return PREGSUB_ERROR; + } + + 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); + } + + } + + *status = dirconf->redirect_status; + return found; + + } + + return NULL; +} + +static char *try_alias_list(request_rec *r, apr_array_header_t *aliases, + int is_redir, 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 *alias = &entries[i]; + int l; + + if (alias->regexp) { + if (!ap_regexec(alias->regexp, r->uri, AP_MAX_REG_MATCH, regm, 0)) { + if (alias->real) { + found = ap_pregsub(r->pool, alias->real, r->uri, + AP_MAX_REG_MATCH, regm); + if (found) { + if (is_redir) { + 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 { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00672) + "Regex substitution in '%s' failed. " + "Replacement too long?", alias->real); + return PREGSUB_ERROR; + } + } + else { + /* need something non-null */ + found = ""; + } + } + } + else { + l = alias_matches(r->uri, alias->fake); + + if (l > 0) { + ap_set_context_info(r, alias->fake, alias->real); + if (is_redir) { + char *escurl; + escurl = ap_os_escape_path(r->pool, r->uri + l, 1); + + found = apr_pstrcat(r->pool, alias->real, escurl, NULL); + } + else + found = apr_pstrcat(r->pool, alias->real, r->uri + l, NULL); + } + } + + if (found) { + if (alias->handler) { /* Set handler, and leave a note for mod_cgi */ + r->handler = alias->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 (!is_redir) { + found = ap_server_root_relative(r->pool, found); + } + if (found) { + *status = alias->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_redirect(r, &status)) != NULL + || (ret = try_alias_list(r, serverconf->redirects, 1, &status)) + != NULL) { + if (ret == PREGSUB_ERROR) + return HTTP_INTERNAL_SERVER_ERROR; + 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, APLOGNO(00673) + "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, APLOGNO(00674) + "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; + } + + if ((ret = try_alias(r)) != NULL + || (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_redirect(r, &status)) != NULL + || (ret = try_alias_list(r, dirconf->redirects, 1, &status)) + != NULL) { + if (ret == PREGSUB_ERROR) + return HTTP_INTERNAL_SERVER_ERROR; + 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, APLOGNO(00675) + "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, APLOGNO(00676) + "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 const command_rec alias_cmds[] = +{ + AP_INIT_TAKE12("Alias", add_alias, NULL, RSRC_CONF | ACCESS_CONF, + "a fakename and a realname, or a realname in a Location"), + AP_INIT_TAKE12("ScriptAlias", add_alias, "cgi-script", RSRC_CONF | ACCESS_CONF, + "a fakename and a realname, or a realname in a Location"), + AP_INIT_TAKE123("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 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); +} + +AP_DECLARE_MODULE(alias) = +{ + 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 */ +}; |