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Diffstat (limited to 'modules/mappers/mod_userdir.c')
| -rw-r--r-- | modules/mappers/mod_userdir.c | 390 |
1 files changed, 390 insertions, 0 deletions
diff --git a/modules/mappers/mod_userdir.c b/modules/mappers/mod_userdir.c new file mode 100644 index 0000000..1ec0e90 --- /dev/null +++ b/modules/mappers/mod_userdir.c @@ -0,0 +1,390 @@ +/* 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. + */ + +/* + * mod_userdir... implement the UserDir command. Broken away from the + * Alias stuff for a couple of good and not-so-good reasons: + * + * 1) It shows a real minimal working example of how to do something like + * this. + * 2) I know people who are actually interested in changing this *particular* + * aspect of server functionality without changing the rest of it. That's + * what this whole modular arrangement is supposed to be good at... + * + * Modified by Alexei Kosut to support the following constructs + * (server running at www.foo.com, request for /~bar/one/two.html) + * + * UserDir public_html -> ~bar/public_html/one/two.html + * UserDir /usr/web -> /usr/web/bar/one/two.html + * UserDir /home/ * /www -> /home/bar/www/one/two.html + * NOTE: theses ^ ^ space only added allow it to work in a comment, ignore + * UserDir http://x/users -> (302) http://x/users/bar/one/two.html + * UserDir http://x/ * /y -> (302) http://x/bar/y/one/two.html + * NOTE: here also ^ ^ + * + * In addition, you can use multiple entries, to specify alternate + * user directories (a la Directory Index). For example: + * + * UserDir public_html /usr/web http://www.xyz.com/users + * + * Modified by Ken Coar to provide for the following: + * + * UserDir disable[d] username ... + * UserDir enable[d] username ... + * + * If "disabled" has no other arguments, *all* ~<username> references are + * disabled, except those explicitly turned on with the "enabled" keyword. + */ + +#include "apr_strings.h" +#include "apr_user.h" + +#define APR_WANT_STRFUNC +#include "apr_want.h" + +#if APR_HAVE_UNISTD_H +#include <unistd.h> +#endif + +#include "ap_config.h" +#include "httpd.h" +#include "http_config.h" +#include "http_request.h" + +#if !defined(WIN32) && !defined(OS2) && !defined(NETWARE) +#define HAVE_UNIX_SUEXEC +#endif + +#ifdef HAVE_UNIX_SUEXEC +#include "unixd.h" /* Contains the suexec_identity hook used on Unix */ +#endif + + +/* + * The default directory in user's home dir + * In the default install, the module is disabled + */ +#ifndef DEFAULT_USER_DIR +#define DEFAULT_USER_DIR NULL +#endif + +#define O_DEFAULT 0 +#define O_ENABLE 1 +#define O_DISABLE 2 + +module AP_MODULE_DECLARE_DATA userdir_module; + +typedef struct { + int globally_disabled; + const char *userdir; + apr_table_t *enabled_users; + apr_table_t *disabled_users; +} userdir_config; + +/* + * Server config for this module: global disablement flag, a list of usernames + * ineligible for UserDir access, a list of those immune to global (but not + * explicit) disablement, and the replacement string for all others. + */ + +static void *create_userdir_config(apr_pool_t *p, server_rec *s) +{ + userdir_config *newcfg = apr_pcalloc(p, sizeof(*newcfg)); + + newcfg->globally_disabled = O_DEFAULT; + newcfg->userdir = DEFAULT_USER_DIR; + newcfg->enabled_users = apr_table_make(p, 4); + newcfg->disabled_users = apr_table_make(p, 4); + + return newcfg; +} + +static void *merge_userdir_config(apr_pool_t *p, void *basev, void *overridesv) +{ + userdir_config *cfg = apr_pcalloc(p, sizeof(userdir_config)); + userdir_config *base = basev, *overrides = overridesv; + + cfg->globally_disabled = (overrides->globally_disabled != O_DEFAULT) ? + overrides->globally_disabled : + base->globally_disabled; + cfg->userdir = (overrides->userdir != DEFAULT_USER_DIR) ? + overrides->userdir : base->userdir; + + /* not merged */ + cfg->enabled_users = overrides->enabled_users; + cfg->disabled_users = overrides->disabled_users; + + return cfg; +} + + +static const char *set_user_dir(cmd_parms *cmd, void *dummy, const char *arg) +{ + userdir_config *s_cfg = ap_get_module_config(cmd->server->module_config, + &userdir_module); + char *username; + const char *usernames = arg; + char *kw = ap_getword_conf(cmd->temp_pool, &usernames); + apr_table_t *usertable; + + /* Since we are a raw argument, it is possible for us to be called with + * zero arguments. So that we aren't ambiguous, flat out reject this. + */ + if (*kw == '\0') { + return "UserDir requires an argument."; + } + + /* + * Let's do the comparisons once. + */ + if ((!strcasecmp(kw, "disable")) || (!strcasecmp(kw, "disabled"))) { + /* + * If there are no usernames specified, this is a global disable - we + * need do no more at this point than record the fact. + */ + if (!*usernames) { + s_cfg->globally_disabled = O_DISABLE; + return NULL; + } + usertable = s_cfg->disabled_users; + } + else if ((!strcasecmp(kw, "enable")) || (!strcasecmp(kw, "enabled"))) { + if (!*usernames) { + s_cfg->globally_disabled = O_ENABLE; + return NULL; + } + usertable = s_cfg->enabled_users; + } + else { + /* + * If the first (only?) value isn't one of our keywords, just copy + * the string to the userdir string. + */ + s_cfg->userdir = arg; + return NULL; + } + /* + * Now we just take each word in turn from the command line and add it to + * the appropriate table. + */ + while (*usernames) { + username = ap_getword_conf(cmd->pool, &usernames); + apr_table_setn(usertable, username, "1"); + } + return NULL; +} + +static const command_rec userdir_cmds[] = { + AP_INIT_RAW_ARGS("UserDir", set_user_dir, NULL, RSRC_CONF, + "the public subdirectory in users' home directories, or " + "'disabled', or 'disabled username username...', or " + "'enabled username username...'"), + {NULL} +}; + +static int translate_userdir(request_rec *r) +{ + ap_conf_vector_t *server_conf; + const userdir_config *s_cfg; + const char *userdirs; + const char *user, *dname; + char *redirect; + apr_finfo_t statbuf; + + /* + * If the URI doesn't match our basic pattern, we've nothing to do with + * it. + */ + if (r->uri[0] != '/' || r->uri[1] != '~') { + return DECLINED; + } + server_conf = r->server->module_config; + s_cfg = ap_get_module_config(server_conf, &userdir_module); + userdirs = s_cfg->userdir; + if (userdirs == NULL) { + return DECLINED; + } + + dname = r->uri + 2; + user = ap_getword(r->pool, &dname, '/'); + + /* + * The 'dname' funny business involves backing it up to capture the '/' + * delimiting the "/~user" part from the rest of the URL, in case there + * was one (the case where there wasn't being just "GET /~user HTTP/1.0", + * for which we don't want to tack on a '/' onto the filename). + */ + + if (dname[-1] == '/') { + --dname; + } + + /* + * If there's no username, it's not for us. Ignore . and .. as well. + */ + if (user[0] == '\0' || + (user[1] == '.' && (user[2] == '\0' || + (user[2] == '.' && user[3] == '\0')))) { + return DECLINED; + } + /* + * Nor if there's an username but it's in the disabled list. + */ + if (apr_table_get(s_cfg->disabled_users, user) != NULL) { + return DECLINED; + } + /* + * If there's a global interdiction on UserDirs, check to see if this + * name is one of the Blessed. + */ + if (s_cfg->globally_disabled == O_DISABLE + && apr_table_get(s_cfg->enabled_users, user) == NULL) { + return DECLINED; + } + + /* + * Special cases all checked, onward to normal substitution processing. + */ + + while (*userdirs) { + const char *userdir = ap_getword_conf(r->pool, &userdirs); + char *filename = NULL, *prefix = NULL; + apr_status_t rv; + int is_absolute = ap_os_is_path_absolute(r->pool, userdir); + + if (ap_strchr_c(userdir, '*')) + prefix = ap_getword(r->pool, &userdir, '*'); + + if (userdir[0] == '\0' || is_absolute) { + if (prefix) { +#ifdef HAVE_DRIVE_LETTERS + /* + * Crummy hack. Need to figure out whether we have been + * redirected to a URL or to a file on some drive. Since I + * know of no protocols that are a single letter, ignore + * a : as the first or second character, and assume a file + * was specified + */ + if (strchr(prefix + 2, ':')) +#else + if (strchr(prefix, ':') && !is_absolute) +#endif /* HAVE_DRIVE_LETTERS */ + { + redirect = apr_pstrcat(r->pool, prefix, user, userdir, + dname, NULL); + apr_table_setn(r->headers_out, "Location", redirect); + return HTTP_MOVED_TEMPORARILY; + } + else + filename = apr_pstrcat(r->pool, prefix, user, userdir, + NULL); + } + else + filename = apr_pstrcat(r->pool, userdir, "/", user, NULL); + } + else if (prefix && ap_strchr_c(prefix, ':')) { + redirect = apr_pstrcat(r->pool, prefix, user, dname, NULL); + apr_table_setn(r->headers_out, "Location", redirect); + return HTTP_MOVED_TEMPORARILY; + } + else { +#if APR_HAS_USER + char *homedir; + + if (apr_uid_homepath_get(&homedir, user, r->pool) == APR_SUCCESS) { + filename = apr_pstrcat(r->pool, homedir, "/", userdir, NULL); + } +#else + return DECLINED; +#endif + } + + /* + * Now see if it exists, or we're at the last entry. If we are at the + * last entry, then use the filename generated (if there is one) + * anyway, in the hope that some handler might handle it. This can be + * used, for example, to run a CGI script for the user. + */ + if (filename && (!*userdirs + || ((rv = apr_stat(&statbuf, filename, APR_FINFO_MIN, + r->pool)) == APR_SUCCESS + || rv == APR_INCOMPLETE))) { + r->filename = apr_pstrcat(r->pool, filename, dname, NULL); + ap_set_context_info(r, apr_pstrmemdup(r->pool, r->uri, + dname - r->uri), + filename); + /* XXX: Does this walk us around FollowSymLink rules? + * When statbuf contains info on r->filename we can save a syscall + * by copying it to r->finfo + */ + if (*userdirs && dname[0] == 0) + r->finfo = statbuf; + + /* For use in the get_suexec_identity phase */ + apr_table_setn(r->notes, "mod_userdir_user", user); + + return OK; + } + } + + return DECLINED; +} + +#ifdef HAVE_UNIX_SUEXEC +static ap_unix_identity_t *get_suexec_id_doer(const request_rec *r) +{ + ap_unix_identity_t *ugid = NULL; +#if APR_HAS_USER + const char *username = apr_table_get(r->notes, "mod_userdir_user"); + + if (username == NULL) { + return NULL; + } + + if ((ugid = apr_palloc(r->pool, sizeof(*ugid))) == NULL) { + return NULL; + } + + if (apr_uid_get(&ugid->uid, &ugid->gid, username, r->pool) != APR_SUCCESS) { + return NULL; + } + + ugid->userdir = 1; +#endif + return ugid; +} +#endif /* HAVE_UNIX_SUEXEC */ + +static void register_hooks(apr_pool_t *p) +{ + static const char * const aszPre[]={ "mod_alias.c",NULL }; + static const char * const aszSucc[]={ "mod_vhost_alias.c",NULL }; + + ap_hook_translate_name(translate_userdir,aszPre,aszSucc,APR_HOOK_MIDDLE); +#ifdef HAVE_UNIX_SUEXEC + ap_hook_get_suexec_identity(get_suexec_id_doer,NULL,NULL,APR_HOOK_FIRST); +#endif +} + +AP_DECLARE_MODULE(userdir) = { + STANDARD20_MODULE_STUFF, + NULL, /* dir config creater */ + NULL, /* dir merger --- default is to override */ + create_userdir_config, /* server config */ + merge_userdir_config, /* merge server config */ + userdir_cmds, /* command apr_table_t */ + register_hooks /* register hooks */ +}; |