solanum-vs-hackint-and-char.../authd/providers/ident.c
2017-08-04 21:01:29 +01:00

383 lines
8.5 KiB
C

/* authd/providers/ident.c - ident 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.
*/
/* Largely adapted from old s_auth.c, but reworked for authd. rDNS code
* moved to its own provider.
*
* --Elizafox 13 March 2016
*/
#include "stdinc.h"
#include "defaults.h"
#include "match.h"
#include "authd.h"
#include "notice.h"
#include "provider.h"
#include "res.h"
#define SELF_PID (ident_provider.id)
#define IDENT_BUFSIZE 128
struct ident_query
{
rb_fde_t *F; /* Our FD */
};
/* Goinked from old s_auth.c --Elizafox */
static const char *messages[] =
{
"*** Checking Ident",
"*** Got Ident response",
"*** No Ident response",
"*** Cannot verify ident validity, ignoring ident",
"*** Ident disabled, not checking ident",
};
typedef enum
{
REPORT_LOOKUP,
REPORT_FOUND,
REPORT_FAIL,
REPORT_INVALID,
REPORT_DISABLED,
} ident_message;
static CNCB ident_connected;
static PF read_ident_reply;
static void client_fail(struct auth_client *auth, ident_message message);
static void client_success(struct auth_client *auth);
static char * get_valid_ident(char *buf);
static int ident_timeout = IDENT_TIMEOUT_DEFAULT;
static bool ident_enable = true;
/*
* ident_connected() - deal with the result of rb_connect_tcp()
*
* If the connection failed, we simply close the auth fd and report
* a failure. If the connection suceeded send the ident server a query
* giving "theirport , ourport". The write is only attempted *once* so
* it is deemed to be a fail if the entire write doesn't write all the
* data given. This shouldnt be a problem since the socket should have
* a write buffer far greater than this message to store it in should
* problems arise. -avalon
*/
static void
ident_connected(rb_fde_t *F __unused, int error, void *data)
{
struct auth_client *auth = data;
struct ident_query *query;
char authbuf[32];
int authlen;
lrb_assert(auth != NULL);
query = get_provider_data(auth, SELF_PID);
lrb_assert(query != NULL);
/* Check the error */
if(error != RB_OK)
{
/* We had an error during connection :( */
client_fail(auth, REPORT_FAIL);
return;
}
snprintf(authbuf, sizeof(authbuf), "%u , %u\r\n",
auth->c_port, auth->l_port);
authlen = strlen(authbuf);
if(rb_write(query->F, authbuf, authlen) != authlen)
{
client_fail(auth, REPORT_FAIL);
return;
}
read_ident_reply(query->F, auth);
}
static void
read_ident_reply(rb_fde_t *F, void *data)
{
struct auth_client *auth = data;
char buf[IDENT_BUFSIZE + 1]; /* buffer to read auth reply into */
ident_message message = REPORT_FAIL;
char *s = NULL;
char *t = NULL;
ssize_t len;
int count;
len = rb_read(F, buf, IDENT_BUFSIZE);
if(len < 0 && rb_ignore_errno(errno))
{
rb_setselect(F, RB_SELECT_READ, read_ident_reply, auth);
return;
}
if(len > 0)
{
if((s = get_valid_ident(buf)) != NULL)
{
t = auth->username;
while (*s == '~' || *s == '^')
s++;
for (count = USERLEN; *s && count; s++)
{
if(*s == '@' || *s == '\r' || *s == '\n')
break;
if(*s != ' ' && *s != ':' && *s != '[')
{
*t++ = *s;
count--;
}
}
*t = '\0';
}
else
message = REPORT_INVALID;
}
if(s == NULL)
client_fail(auth, message);
else
client_success(auth);
}
static void
client_fail(struct auth_client *auth, ident_message report)
{
struct ident_query *query = get_provider_data(auth, SELF_PID);
lrb_assert(query != NULL);
rb_strlcpy(auth->username, "*", sizeof(auth->username));
if(query->F != NULL)
rb_close(query->F);
rb_free(query);
set_provider_data(auth, SELF_PID, NULL);
set_provider_timeout_absolute(auth, SELF_PID, 0);
notice_client(auth->cid, messages[report]);
provider_done(auth, SELF_PID);
auth_client_unref(auth);
}
static void
client_success(struct auth_client *auth)
{
struct ident_query *query = get_provider_data(auth, SELF_PID);
lrb_assert(query != NULL);
if(query->F != NULL)
rb_close(query->F);
rb_free(query);
set_provider_data(auth, SELF_PID, NULL);
set_provider_timeout_absolute(auth, SELF_PID, 0);
notice_client(auth->cid, messages[REPORT_FOUND]);
provider_done(auth, SELF_PID);
auth_client_unref(auth);
}
/* get_valid_ident
* parse ident query reply from identd server
*
* Taken from old s_auth.c --Elizafox
*
* Inputs - pointer to ident buf
* Outputs - NULL if no valid ident found, otherwise pointer to name
* Side effects - None
*/
static char *
get_valid_ident(char *buf)
{
int remp = 0;
int locp = 0;
char *colon1Ptr;
char *colon2Ptr;
char *colon3Ptr;
char *commaPtr;
char *remotePortString;
/* All this to get rid of a sscanf() fun. */
remotePortString = buf;
colon1Ptr = strchr(remotePortString, ':');
if(!colon1Ptr)
return NULL;
*colon1Ptr = '\0';
colon1Ptr++;
colon2Ptr = strchr(colon1Ptr, ':');
if(!colon2Ptr)
return NULL;
*colon2Ptr = '\0';
colon2Ptr++;
commaPtr = strchr(remotePortString, ',');
if(!commaPtr)
return NULL;
*commaPtr = '\0';
commaPtr++;
remp = atoi(remotePortString);
if(!remp)
return NULL;
locp = atoi(commaPtr);
if(!locp)
return NULL;
/* look for USERID bordered by first pair of colons */
if(!strstr(colon1Ptr, "USERID"))
return NULL;
colon3Ptr = strchr(colon2Ptr, ':');
if(!colon3Ptr)
return NULL;
*colon3Ptr = '\0';
colon3Ptr++;
return (colon3Ptr);
}
static void
ident_destroy(void)
{
struct auth_client *auth;
rb_dictionary_iter iter;
/* Nuke all ident queries */
RB_DICTIONARY_FOREACH(auth, &iter, auth_clients)
{
if(get_provider_data(auth, SELF_PID) != NULL)
client_fail(auth, REPORT_FAIL);
/* auth is now invalid as we have no reference */
}
}
static bool
ident_start(struct auth_client *auth)
{
struct ident_query *query = rb_malloc(sizeof(struct ident_query));
struct rb_sockaddr_storage l_addr, c_addr;
int family = GET_SS_FAMILY(&auth->c_addr);
lrb_assert(get_provider_data(auth, SELF_PID) == NULL);
if(!ident_enable)
{
rb_free(query);
notice_client(auth->cid, messages[REPORT_DISABLED]);
set_provider_done(auth, SELF_PID);
return true;
}
auth_client_ref(auth);
notice_client(auth->cid, messages[REPORT_LOOKUP]);
set_provider_data(auth, SELF_PID, query);
set_provider_timeout_relative(auth, SELF_PID, ident_timeout);
if((query->F = rb_socket(family, SOCK_STREAM, 0, "ident")) == NULL)
{
warn_opers(L_DEBUG, "Could not create ident socket: %s", strerror(errno));
client_fail(auth, REPORT_FAIL);
return true; /* Not a fatal error */
}
/* Build sockaddr_storages for rb_connect_tcp below */
l_addr = auth->l_addr;
c_addr = auth->c_addr;
SET_SS_PORT(&l_addr, 0);
SET_SS_PORT(&c_addr, htons(113));
rb_connect_tcp(query->F, (struct sockaddr *)&c_addr,
(struct sockaddr *)&l_addr,
ident_connected,
auth, ident_timeout);
set_provider_running(auth, SELF_PID);
return true;
}
static void
ident_cancel(struct auth_client *auth)
{
struct ident_query *query = get_provider_data(auth, SELF_PID);
if(query != NULL)
client_fail(auth, REPORT_FAIL);
}
static void
add_conf_ident_timeout(const char *key __unused, int parc __unused, const char **parv)
{
int timeout = atoi(parv[0]);
if(timeout < 0)
{
warn_opers(L_CRIT, "Ident: ident timeout < 0 (value: %d)", timeout);
exit(EX_PROVIDER_ERROR);
}
ident_timeout = timeout;
}
static void
set_ident_enabled(const char *key __unused, int parc __unused, const char **parv)
{
ident_enable = (*parv[0] == '1');
}
struct auth_opts_handler ident_options[] =
{
{ "ident_timeout", 1, add_conf_ident_timeout },
{ "ident_enabled", 1, set_ident_enabled },
{ NULL, 0, NULL },
};
struct auth_provider ident_provider =
{
.name = "ident",
.letter = 'I',
.start = ident_start,
.destroy = ident_destroy,
.cancel = ident_cancel,
.timeout = ident_cancel,
.opt_handlers = ident_options,
};