authd: add rdns provider (compile-tested)

This commit is contained in:
Elizabeth Myers 2016-03-10 08:04:17 -06:00
parent 5bfc606fa4
commit 187643195c
4 changed files with 238 additions and 15 deletions

View file

@ -3,5 +3,11 @@ AM_CFLAGS=$(WARNFLAGS)
AM_CPPFLAGS = -I../include -I../librb/include AM_CPPFLAGS = -I../include -I../librb/include
authd_SOURCES = provider.c authd.c res.c reslib.c dns.c authd_SOURCES = provider.c \
authd.c \
res.c \
reslib.c \
dns.c \
providers/rdns.c
authd_LDADD = ../librb/src/librb.la authd_LDADD = ../librb/src/librb.la

View file

@ -66,17 +66,7 @@ void unload_provider(struct auth_provider *provider)
/* Initalise all providers */ /* Initalise all providers */
void init_providers(void) void init_providers(void)
{ {
rb_dlink_node *ptr; load_provider(&rdns_provider);
struct auth_provider *provider;
RB_DLINK_FOREACH(ptr, auth_providers.head)
{
provider = ptr->data;
if(provider->init && !provider->init())
/* Provider failed to init, time to go */
exit(1);
}
} }
/* Terminate all providers */ /* Terminate all providers */
@ -184,7 +174,7 @@ void notice_client(struct auth_client *auth, const char *notice)
} }
/* Begin authenticating user */ /* Begin authenticating user */
static void start_auth(const char *cid, const char *l_ip, const char *l_port, const char *c_ip, const char *c_port) static void start_auth(const char *cid, const char *l_ip, const char *l_port, const char *c_addr, const char *c_port)
{ {
rb_dlink_node *ptr; rb_dlink_node *ptr;
struct auth_provider *provider; struct auth_provider *provider;
@ -204,7 +194,7 @@ static void start_auth(const char *cid, const char *l_ip, const char *l_port, co
(void)rb_inet_pton_sock(l_ip, (struct sockaddr *)&auth->l_ip); (void)rb_inet_pton_sock(l_ip, (struct sockaddr *)&auth->l_ip);
auth->l_port = (uint16_t)atoi(l_port); /* Safe cast, port shouldn't exceed 16 bits */ auth->l_port = (uint16_t)atoi(l_port); /* Safe cast, port shouldn't exceed 16 bits */
(void)rb_inet_pton_sock(c_ip, (struct sockaddr *)&auth->c_ip); (void)rb_inet_pton_sock(c_addr, (struct sockaddr *)&auth->c_addr);
auth->c_port = (uint16_t)atoi(c_port); auth->c_port = (uint16_t)atoi(c_port);
RB_DLINK_FOREACH(ptr, auth_providers.head) RB_DLINK_FOREACH(ptr, auth_providers.head)

View file

@ -42,7 +42,7 @@ struct auth_client
struct rb_sockaddr_storage l_ip; /* Listener IP address */ struct rb_sockaddr_storage l_ip; /* Listener IP address */
uint16_t l_port; /* Listener port */ uint16_t l_port; /* Listener port */
struct rb_sockaddr_storage c_ip; /* Client IP address */ struct rb_sockaddr_storage c_addr; /* Client IP address */
uint16_t c_port; /* Client port */ uint16_t c_port; /* Client port */
char hostname[HOSTLEN + 1]; /* Used for DNS lookup */ char hostname[HOSTLEN + 1]; /* Used for DNS lookup */
@ -73,6 +73,7 @@ struct auth_provider
}; };
extern rb_dlink_list auth_providers; extern rb_dlink_list auth_providers;
extern struct auth_provider rdns_provider;
extern struct auth_client auth_clients[MAX_CLIENTS]; extern struct auth_client auth_clients[MAX_CLIENTS];

226
authd/providers/rdns.c Normal file
View file

@ -0,0 +1,226 @@
/* authd/providers/rdns.c - rDNS lookup provider for authd
* Copyright (c) 2016 Elizabeth Myers <elizabeth@interlinked.me>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice is present in all copies.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "stdinc.h"
#include "rb_commio.h"
#include "authd.h"
#include "provider.h"
#include "res.h"
#include "dns.h"
struct dns_query
{
rb_dlink_node node;
struct auth_client *auth; /* Our client */
struct DNSQuery query; /* DNS query */
time_t timeout; /* When the request times out */
};
/* Goinked from old s_auth.c --Elizabeth */
static const char *messages[] =
{
"*** Looking up your hostname...",
"*** Found your hostname",
"*** Couldn't look up your hostname",
"*** Your hostname is too long, ignoring hostname",
};
typedef enum
{
REPORT_LOOKUP,
REPORT_FOUND,
REPORT_FAIL,
REPORT_TOOLONG,
} dns_message;
static EVH timeout_dns_queries_event;
static void client_fail(struct dns_query *query, dns_message message);
static void client_success(struct dns_query *query);
static void get_dns_answer(void *userdata, struct DNSReply *reply);
rb_dlink_list queries;
static struct ev_entry *timeout_ev;
int timeout = 30;
bool client_dns_init(void)
{
timeout_ev = rb_event_addish("timeout_dns_queries_event", timeout_dns_queries_event, NULL, 1);
return (timeout_ev != NULL);
}
void client_dns_destroy(void)
{
rb_dlink_node *ptr, *nptr;
struct dns_query *query;
RB_DLINK_FOREACH_SAFE(ptr, nptr, queries.head)
{
client_fail(ptr->data, REPORT_FAIL);
rb_dlinkDelete(ptr, &queries);
rb_free(ptr);
}
rb_event_delete(timeout_ev);
}
bool client_dns_start(struct auth_client *auth)
{
struct dns_query *query = rb_malloc(sizeof(struct dns_query));
query->auth = auth;
query->timeout = rb_current_time() + timeout;
query->query.ptr = query;
query->query.callback = get_dns_answer;
gethost_byaddr(&auth->c_addr, &query->query);
notice_client(auth, messages[REPORT_LOOKUP]);
return true;
}
void client_dns_cancel(struct auth_client *auth)
{
rb_dlink_node *ptr;
/* Bah, the stupid DNS resolver code doesn't have a cancellation
* func... */
RB_DLINK_FOREACH(ptr, queries.head)
{
struct dns_query *query = ptr->data;
if(query->auth == auth)
{
/* This will get cleaned up later by the DNS stuff */
client_fail(query, REPORT_FAIL);
return;
}
}
}
static void
get_dns_answer(void *userdata, struct DNSReply *reply)
{
struct dns_query *query = userdata;
struct auth_client *auth = query->auth;
rb_dlink_node *ptr, *nptr;
bool fail = false;
dns_message response;
if(reply == NULL || auth == NULL)
{
response = REPORT_FAIL;
fail = true;
goto cleanup;
}
if(!sockcmp(&auth->c_addr, &reply->addr, GET_SS_FAMILY(&auth->c_addr)))
{
response = REPORT_FAIL;
fail = true;
goto cleanup;
}
if(strlen(reply->h_name) > HOSTLEN)
{
/* Ah well. */
response = REPORT_TOOLONG;
fail = true;
goto cleanup;
}
rb_strlcpy(auth->hostname, reply->h_name, HOSTLEN + 1);
cleanup:
/* Clean us up off the pending queries list */
RB_DLINK_FOREACH_SAFE(ptr, nptr, queries.head)
{
struct dns_query *query_l = ptr->data;
if(query == query_l)
{
/* Found */
if(fail)
client_fail(query, response);
else
client_success(query);
rb_dlinkDelete(ptr, &queries);
rb_free(query);
return;
}
}
}
/* Timeout outstanding queries */
static void timeout_dns_queries_event(void *notused)
{
rb_dlink_node *ptr;
/* NOTE - we do not delete queries from the list from a timeout, when
* the query times out later it will be deleted.
*/
RB_DLINK_FOREACH(ptr, queries.head)
{
struct dns_query *query = ptr->data;
if(query->auth && query->timeout < rb_current_time())
{
client_fail(query, REPORT_FAIL);
return;
}
}
}
static void client_fail(struct dns_query *query, dns_message report)
{
struct auth_client *auth = query->auth;
if(auth)
{
rb_strlcpy(auth->hostname, "*", sizeof(auth->hostname));
notice_client(auth, messages[report]);
provider_done(auth, PROVIDER_RDNS);
query->auth = NULL;
}
}
static void client_success(struct dns_query *query)
{
struct auth_client *auth = query->auth;
if(auth)
{
notice_client(auth, messages[REPORT_FOUND]);
provider_done(auth, PROVIDER_RDNS);
query->auth = NULL;
}
}
struct auth_provider rdns_provider =
{
.id = PROVIDER_RDNS,
.init = client_dns_init,
.destroy = client_dns_destroy,
.start = client_dns_start,
.cancel = client_dns_cancel,
.completed = NULL,
};