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Diffstat (limited to '')
| -rw-r--r-- | modules/aaa/mod_authz_host.c | 410 |
1 files changed, 410 insertions, 0 deletions
diff --git a/modules/aaa/mod_authz_host.c b/modules/aaa/mod_authz_host.c new file mode 100644 index 0000000..b43414f --- /dev/null +++ b/modules/aaa/mod_authz_host.c @@ -0,0 +1,410 @@ +/* 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. + */ + +/* + * Security options etc. + * + * Module derived from code originally written by Rob McCool + * + */ + +#include "apr_strings.h" +#include "apr_network_io.h" +#include "apr_md5.h" +#include "apr_hash.h" + +#define APR_WANT_STRFUNC +#define APR_WANT_BYTEFUNC +#include "apr_want.h" + +#include "ap_config.h" +#include "ap_provider.h" +#include "httpd.h" +#include "http_core.h" +#include "http_config.h" +#include "http_log.h" +#include "http_protocol.h" +#include "http_request.h" + +#include "mod_auth.h" + +#if APR_HAVE_NETINET_IN_H +#include <netinet/in.h> +#endif + +/* + * To save memory if the same subnets are used in hundres of vhosts, we store + * each subnet only once and use this temporary hash to find it again. + */ +static apr_hash_t *parsed_subnets; + +static apr_ipsubnet_t *localhost_v4; +#if APR_HAVE_IPV6 +static apr_ipsubnet_t *localhost_v6; +#endif + +static int in_domain(const char *domain, const char *what) +{ + int dl = strlen(domain); + int wl = strlen(what); + + if ((wl - dl) >= 0) { + if (strcasecmp(domain, &what[wl - dl]) != 0) { + return 0; + } + + /* Make sure we matched an *entire* subdomain --- if the user + * said 'allow from good.com', we don't want people from nogood.com + * to be able to get in. + */ + + if (wl == dl) { + return 1; /* matched whole thing */ + } + else { + return (domain[0] == '.' || what[wl - dl - 1] == '.'); + } + } + else { + return 0; + } +} + +static const char *ip_parse_config(cmd_parms *cmd, + const char *require_line, + const void **parsed_require_line) +{ + const char *t, *w; + int count = 0; + apr_ipsubnet_t **ip; + apr_pool_t *ptemp = cmd->temp_pool; + apr_pool_t *p = cmd->pool; + + /* The 'ip' provider will allow the configuration to specify a list of + ip addresses to check rather than a single address. This is different + from the previous host based syntax. */ + + t = require_line; + while ((w = ap_getword_conf(ptemp, &t)) && w[0]) + count++; + + if (count == 0) + return "'require ip' requires an argument"; + + ip = apr_pcalloc(p, sizeof(apr_ipsubnet_t *) * (count + 1)); + *parsed_require_line = ip; + + t = require_line; + while ((w = ap_getword_conf(ptemp, &t)) && w[0]) { + char *addr = apr_pstrdup(ptemp, w); + char *mask; + apr_status_t rv; + + if (parsed_subnets && + (*ip = apr_hash_get(parsed_subnets, w, APR_HASH_KEY_STRING)) != NULL) + { + /* we already have parsed this subnet */ + ip++; + continue; + } + + if ((mask = ap_strchr(addr, '/'))) + *mask++ = '\0'; + + rv = apr_ipsubnet_create(ip, addr, mask, p); + + if(APR_STATUS_IS_EINVAL(rv)) { + /* looked nothing like an IP address */ + return apr_psprintf(p, "ip address '%s' appears to be invalid", w); + } + else if (rv != APR_SUCCESS) { + return apr_psprintf(p, "ip address '%s' appears to be invalid: %pm", + w, &rv); + } + + if (parsed_subnets) + apr_hash_set(parsed_subnets, w, APR_HASH_KEY_STRING, *ip); + ip++; + } + + return NULL; +} + +static authz_status ip_check_authorization(request_rec *r, + const char *require_line, + const void *parsed_require_line) +{ + /* apr_ipsubnet_test should accept const but doesn't */ + apr_ipsubnet_t **ip = (apr_ipsubnet_t **)parsed_require_line; + + while (*ip) { + if (apr_ipsubnet_test(*ip, r->useragent_addr)) + return AUTHZ_GRANTED; + ip++; + } + + /* authz_core will log the require line and the result at DEBUG */ + return AUTHZ_DENIED; +} + +static authz_status host_check_authorization(request_rec *r, + const char *require_line, + const void *parsed_require_line) +{ + const char *t, *w; + const char *remotehost = NULL; + int remotehost_is_ip; + + remotehost = ap_get_useragent_host(r, REMOTE_DOUBLE_REV, &remotehost_is_ip); + + if ((remotehost == NULL) || remotehost_is_ip) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01753) + "access check of '%s' to %s failed, reason: unable to get the " + "remote host name", require_line, r->uri); + } + else { + const char *err = NULL; + const ap_expr_info_t *expr = parsed_require_line; + const char *require; + + require = ap_expr_str_exec(r, expr, &err); + if (err) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02593) + "authz_host authorize: require host: Can't " + "evaluate require expression: %s", err); + return AUTHZ_DENIED; + } + + /* The 'host' provider will allow the configuration to specify a list of + host names to check rather than a single name. This is different + from the previous host based syntax. */ + t = require; + + /* '#' is not a valid hostname character and admin could + * specify 'Require host localhost# Add example.com later'. We + * should not grant access to 'example.com' in that case. */ + w = ap_strchr_c(t, '#'); + if (w) { + if (w == t) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(10120) + "authz_host authorize: dubious empty " + "'Require host %s' with only comment", t); + return AUTHZ_DENIED; + } + + ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(10121) + "authz_host authorize: ignoring comment in " + "'Require host %s'", t); + + /* Truncate the string at the #. */ + t = apr_pstrmemdup(r->pool, t, w - t); + } + + while ((w = ap_getword_conf(r->pool, &t)) && w[0]) { + if (in_domain(w, remotehost)) { + return AUTHZ_GRANTED; + } + } + } + + /* authz_core will log the require line and the result at DEBUG */ + return AUTHZ_DENIED; +} + +static authz_status +forward_dns_check_authorization(request_rec *r, + const char *require_line, + const void *parsed_require_line) +{ + const char *err = NULL; + const ap_expr_info_t *expr = parsed_require_line; + const char *require, *t; + char *w; + + /* the require line is an expression, which is evaluated now. */ + require = ap_expr_str_exec(r, expr, &err); + if (err) { + ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(03354) + "authz_host authorize: require forward-dns: " + "Can't evaluate require expression: %s", err); + return AUTHZ_DENIED; + } + + /* tokenize expected list of names */ + t = require; + while ((w = ap_getword_conf(r->pool, &t)) && w[0]) { + + apr_sockaddr_t *sa; + apr_status_t rv; + char *hash_ptr; + + /* stop on apache configuration file comments */ + if ((hash_ptr = ap_strchr(w, '#'))) { + if (hash_ptr == w) { + break; + } + *hash_ptr = '\0'; + } + + /* does the client ip match one of the names? */ + rv = apr_sockaddr_info_get(&sa, w, APR_UNSPEC, 0, 0, r->pool); + if (rv == APR_SUCCESS) { + + while (sa) { + int match = apr_sockaddr_equal(sa, r->useragent_addr); + + ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(03355) + "access check for %s as '%s': %s", + r->useragent_ip, w, match? "yes": "no"); + if (match) { + return AUTHZ_GRANTED; + } + + sa = sa->next; + } + } + else { + ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, APLOGNO(03356) + "No sockaddr info for \"%s\"", w); + } + + /* stop processing, we are in a comment */ + if (hash_ptr) { + break; + } + } + + return AUTHZ_DENIED; +} + +static authz_status local_check_authorization(request_rec *r, + const char *require_line, + const void *parsed_require_line) +{ + if ( apr_sockaddr_equal(r->connection->local_addr, + r->useragent_addr) + || apr_ipsubnet_test(localhost_v4, r->useragent_addr) +#if APR_HAVE_IPV6 + || apr_ipsubnet_test(localhost_v6, r->useragent_addr) +#endif + ) + { + return AUTHZ_GRANTED; + } + + return AUTHZ_DENIED; +} + +static const char *host_parse_config(cmd_parms *cmd, const char *require_line, + const void **parsed_require_line) +{ + const char *expr_err = NULL; + ap_expr_info_t *expr; + + expr = ap_expr_parse_cmd(cmd, require_line, AP_EXPR_FLAG_STRING_RESULT, + &expr_err, NULL); + + if (expr_err) + return apr_pstrcat(cmd->temp_pool, + "Cannot parse expression in require line: ", + expr_err, NULL); + + *parsed_require_line = expr; + + return NULL; +} + +static const authz_provider authz_ip_provider = +{ + &ip_check_authorization, + &ip_parse_config, +}; + +static const authz_provider authz_host_provider = +{ + &host_check_authorization, + &host_parse_config, +}; + +static const authz_provider authz_forward_dns_provider = +{ + &forward_dns_check_authorization, + &host_parse_config, +}; + +static const authz_provider authz_local_provider = +{ + &local_check_authorization, + NULL, +}; + + +static int authz_host_pre_config(apr_pool_t *p, apr_pool_t *plog, + apr_pool_t *ptemp) +{ + /* we only use this hash in the parse config phase, ptemp is enough */ + parsed_subnets = apr_hash_make(ptemp); + + apr_ipsubnet_create(&localhost_v4, "127.0.0.0", "8", p); + apr_hash_set(parsed_subnets, "127.0.0.0/8", APR_HASH_KEY_STRING, localhost_v4); + +#if APR_HAVE_IPV6 + apr_ipsubnet_create(&localhost_v6, "::1", NULL, p); + apr_hash_set(parsed_subnets, "::1", APR_HASH_KEY_STRING, localhost_v6); +#endif + + return OK; +} + +static int authz_host_post_config(apr_pool_t *p, apr_pool_t *plog, + apr_pool_t *ptemp, server_rec *s) +{ + /* make sure we don't use this during .htaccess parsing */ + parsed_subnets = NULL; + + return OK; +} + +static void register_hooks(apr_pool_t *p) +{ + ap_hook_pre_config(authz_host_pre_config, NULL, NULL, APR_HOOK_MIDDLE); + ap_hook_post_config(authz_host_post_config, NULL, NULL, APR_HOOK_MIDDLE); + + ap_register_auth_provider(p, AUTHZ_PROVIDER_GROUP, "ip", + AUTHZ_PROVIDER_VERSION, + &authz_ip_provider, AP_AUTH_INTERNAL_PER_CONF); + ap_register_auth_provider(p, AUTHZ_PROVIDER_GROUP, "host", + AUTHZ_PROVIDER_VERSION, + &authz_host_provider, AP_AUTH_INTERNAL_PER_CONF); + ap_register_auth_provider(p, AUTHZ_PROVIDER_GROUP, "forward-dns", + AUTHZ_PROVIDER_VERSION, + &authz_forward_dns_provider, + AP_AUTH_INTERNAL_PER_CONF); + ap_register_auth_provider(p, AUTHZ_PROVIDER_GROUP, "local", + AUTHZ_PROVIDER_VERSION, + &authz_local_provider, AP_AUTH_INTERNAL_PER_CONF); +} + +AP_DECLARE_MODULE(authz_host) = +{ + STANDARD20_MODULE_STUFF, + NULL, /* dir config creater */ + NULL, /* dir merger --- default is to override */ + NULL, /* server config */ + NULL, /* merge server config */ + NULL, + register_hooks /* register hooks */ +}; |