elemental-ircd/src/hostmask.c

774 lines
20 KiB
C

/*
* charybdis: an advanced internet relay chat daemon (ircd).
* hostmask.c: Code to efficiently find IP & hostmask based configs.
*
* Copyright (C) 1990 Jarkko Oikarinen and University of Oulu, Co Center
* Copyright (C) 1996-2002 Hybrid Development Team
* Copyright (C) 2002-2005 ircd-ratbox development team
* Copyright (C) 2005-2008 charybdis development team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
* $Id: hostmask.c 2757 2006-11-10 22:58:15Z jilles $
*/
#include "stdinc.h"
#include "ircd_defs.h"
#include "s_conf.h"
#include "hostmask.h"
#include "numeric.h"
#include "send.h"
#include "match.h"
#ifdef RB_IPV6
static unsigned long hash_ipv6(struct sockaddr *, int);
#endif
static unsigned long hash_ipv4(struct sockaddr *, int);
/* int parse_netmask(const char *, struct rb_sockaddr_storage *, int *);
* Input: A hostmask, or an IPV4/6 address.
* Output: An integer describing whether it is an IPV4, IPV6 address or a
* hostmask, an address(if it is an IP mask),
* a bitlength(if it is IP mask).
* Side effects: None
*/
int
parse_netmask(const char *text, struct sockaddr *naddr, int *nb)
{
char *ip = LOCAL_COPY(text);
char *ptr;
struct rb_sockaddr_storage *addr, xaddr;
int *b, xb;
if(nb == NULL)
b = &xb;
else
b = nb;
if(naddr == NULL)
addr = (struct rb_sockaddr_storage *)&xaddr;
else
addr = (struct rb_sockaddr_storage *)naddr;
if(strpbrk(ip, "*?") != NULL)
{
return HM_HOST;
}
#ifdef RB_IPV6
if(strchr(ip, ':'))
{
if((ptr = strchr(ip, '/')))
{
*ptr = '\0';
ptr++;
*b = atoi(ptr);
if(*b > 128)
*b = 128;
} else
*b = 128;
if(rb_inet_pton_sock(ip, (struct sockaddr *)addr) > 0)
return HM_IPV6;
else
return HM_HOST;
} else
#endif
if(strchr(text, '.'))
{
if((ptr = strchr(ip, '/')))
{
*ptr = '\0';
ptr++;
*b = atoi(ptr);
if(*b > 32)
*b = 32;
} else
*b = 32;
if(rb_inet_pton_sock(ip, (struct sockaddr *)addr) > 0)
return HM_IPV4;
else
return HM_HOST;
}
return HM_HOST;
}
/* Hashtable stuff...now external as its used in m_stats.c */
struct AddressRec *atable[ATABLE_SIZE];
void
init_host_hash(void)
{
memset(&atable, 0, sizeof(atable));
}
/* unsigned long hash_ipv4(struct rb_sockaddr_storage*)
* Input: An IP address.
* Output: A hash value of the IP address.
* Side effects: None
*/
static unsigned long
hash_ipv4(struct sockaddr *saddr, int bits)
{
struct sockaddr_in *addr = (struct sockaddr_in *) saddr;
if(bits != 0)
{
unsigned long av = ntohl(addr->sin_addr.s_addr) & ~((1 << (32 - bits)) - 1);
return (av ^ (av >> 12) ^ (av >> 24)) & (ATABLE_SIZE - 1);
}
return 0;
}
/* unsigned long hash_ipv6(struct rb_sockaddr_storage*)
* Input: An IP address.
* Output: A hash value of the IP address.
* Side effects: None
*/
#ifdef RB_IPV6
static unsigned long
hash_ipv6(struct sockaddr *saddr, int bits)
{
struct sockaddr_in6 *addr = (struct sockaddr_in6 *) saddr;
unsigned long v = 0, n;
for (n = 0; n < 16; n++)
{
if(bits >= 8)
{
v ^= addr->sin6_addr.s6_addr[n];
bits -= 8;
}
else if(bits)
{
v ^= addr->sin6_addr.s6_addr[n] & ~((1 << (8 - bits)) - 1);
return v & (ATABLE_SIZE - 1);
}
else
return v & (ATABLE_SIZE - 1);
}
return v & (ATABLE_SIZE - 1);
}
#endif
/* int hash_text(const char *start)
* Input: The start of the text to hash.
* Output: The hash of the string between 1 and (TH_MAX-1)
* Side-effects: None.
*/
static int
hash_text(const char *start)
{
const char *p = start;
unsigned long h = 0;
while(*p)
{
h = (h << 4) - (h + (unsigned char) ToLower(*p++));
}
return (h & (ATABLE_SIZE - 1));
}
/* unsigned long get_hash_mask(const char *)
* Input: The text to hash.
* Output: The hash of the string right of the first '.' past the last
* wildcard in the string.
* Side-effects: None.
*/
static unsigned long
get_mask_hash(const char *text)
{
const char *hp = "", *p;
for (p = text + strlen(text) - 1; p >= text; p--)
if(*p == '*' || *p == '?')
return hash_text(hp);
else if(*p == '.')
hp = p + 1;
return hash_text(text);
}
/* struct ConfItem* find_conf_by_address(const char*, struct rb_sockaddr_storage*,
* int type, int fam, const char *username)
* Input: The hostname, the address, the type of mask to find, the address
* family, the username.
* Output: The matching value with the highest precedence.
* Side-effects: None
* Note: Setting bit 0 of the type means that the username is ignored.
*/
struct ConfItem *
find_conf_by_address(const char *name, const char *sockhost,
const char *orighost,
struct sockaddr *addr, int type, int fam,
const char *username, const char *auth_user)
{
unsigned long hprecv = 0;
struct ConfItem *hprec = NULL;
struct AddressRec *arec;
int b;
if(username == NULL)
username = "";
if(addr)
{
/* Check for IPV6 matches... */
#ifdef RB_IPV6
if(fam == AF_INET6)
{
for (b = 128; b >= 0; b -= 16)
{
for (arec = atable[hash_ipv6(addr, b)]; arec; arec = arec->next)
if(arec->type == (type & ~0x1) &&
arec->masktype == HM_IPV6 &&
comp_with_mask_sock(addr, (struct sockaddr *)&arec->Mask.ipa.addr,
arec->Mask.ipa.bits) &&
(type & 0x1 || match(arec-> username, username)) &&
(type != CONF_CLIENT || !arec->auth_user ||
(auth_user && match(arec->auth_user, auth_user))) &&
arec->precedence > hprecv)
{
hprecv = arec->precedence;
hprec = arec->aconf;
}
}
}
else
#endif
if(fam == AF_INET)
{
for (b = 32; b >= 0; b -= 8)
{
for (arec = atable[hash_ipv4(addr, b)]; arec; arec = arec->next)
if(arec->type == (type & ~0x1) &&
arec->masktype == HM_IPV4 &&
comp_with_mask_sock(addr, (struct sockaddr *)&arec->Mask.ipa.addr,
arec->Mask.ipa.bits) &&
(type & 0x1 || match(arec->username, username)) &&
(type != CONF_CLIENT || !arec->auth_user ||
(auth_user && match(arec->auth_user, auth_user))) &&
arec->precedence > hprecv)
{
hprecv = arec->precedence;
hprec = arec->aconf;
}
}
}
}
if(orighost != NULL)
{
const char *p;
for (p = orighost; p != NULL;)
{
for (arec = atable[hash_text(p)]; arec; arec = arec->next)
if((arec->type == (type & ~0x1)) &&
(arec->masktype == HM_HOST) &&
arec->precedence > hprecv &&
match(arec->Mask.hostname, orighost) &&
(type != CONF_CLIENT || !arec->auth_user ||
(auth_user && match(arec->auth_user, auth_user))) &&
(type & 0x1 || match(arec->username, username)))
{
hprecv = arec->precedence;
hprec = arec->aconf;
}
p = strchr(p, '.');
if(p != NULL)
p++;
else
break;
}
for (arec = atable[0]; arec; arec = arec->next)
{
if(arec->type == (type & ~0x1) &&
arec->masktype == HM_HOST &&
arec->precedence > hprecv &&
(match(arec->Mask.hostname, orighost) ||
(sockhost && match(arec->Mask.hostname, sockhost))) &&
(type != CONF_CLIENT || !arec->auth_user ||
(auth_user && match(arec->auth_user, auth_user))) &&
(type & 0x1 || match(arec->username, username)))
{
hprecv = arec->precedence;
hprec = arec->aconf;
}
}
}
if(name != NULL)
{
const char *p;
/* And yes - we have to check p after strchr and p after increment for
* NULL -kre */
for (p = name; p != NULL;)
{
for (arec = atable[hash_text(p)]; arec; arec = arec->next)
if((arec->type == (type & ~0x1)) &&
(arec->masktype == HM_HOST) &&
arec->precedence > hprecv &&
match(arec->Mask.hostname, name) &&
(type != CONF_CLIENT || !arec->auth_user ||
(auth_user && match(arec->auth_user, auth_user))) &&
(type & 0x1 || match(arec->username, username)))
{
hprecv = arec->precedence;
hprec = arec->aconf;
}
p = strchr(p, '.');
if(p != NULL)
p++;
else
break;
}
for (arec = atable[0]; arec; arec = arec->next)
{
if(arec->type == (type & ~0x1) &&
arec->masktype == HM_HOST &&
arec->precedence > hprecv &&
(match(arec->Mask.hostname, name) ||
(sockhost && match(arec->Mask.hostname, sockhost))) &&
(type != CONF_CLIENT || !arec->auth_user ||
(auth_user && match(arec->auth_user, auth_user))) &&
(type & 0x1 || match(arec->username, username)))
{
hprecv = arec->precedence;
hprec = arec->aconf;
}
}
}
return hprec;
}
/* struct ConfItem* find_address_conf(const char*, const char*,
* struct rb_sockaddr_storage*, int);
* Input: The hostname, username, address, address family.
* Output: The applicable ConfItem.
* Side-effects: None
*/
struct ConfItem *
find_address_conf(const char *host, const char *sockhost, const char *user,
const char *notildeuser, struct sockaddr *ip, int aftype, char *auth_user)
{
struct ConfItem *iconf, *kconf;
const char *vuser;
/* Find the best I-line... If none, return NULL -A1kmm */
if(!(iconf = find_conf_by_address(host, sockhost, NULL, ip, CONF_CLIENT, aftype, user, auth_user)))
return NULL;
/* Find what their visible username will be.
* Note that the username without tilde may contain one char more.
* -- jilles */
vuser = IsNoTilde(iconf) ? notildeuser : user;
/* If they are exempt from K-lines, return the best I-line. -A1kmm */
if(IsConfExemptKline(iconf))
return iconf;
/* Find the best K-line... -A1kmm */
kconf = find_conf_by_address(host, sockhost, NULL, ip, CONF_KILL, aftype, user, NULL);
/* If they are K-lined, return the K-line */
if(kconf)
return kconf;
/* if theres a spoof, check it against klines.. */
if(IsConfDoSpoofIp(iconf))
{
char *p = strchr(iconf->name, '@');
/* note, we dont need to pass sockhost here, as its
* guaranteed to not match by whats above.. --anfl
*/
if(p)
{
*p = '\0';
kconf = find_conf_by_address(p+1, NULL, NULL, ip, CONF_KILL, aftype, iconf->name, NULL);
*p = '@';
}
else
kconf = find_conf_by_address(iconf->name, NULL, NULL, ip, CONF_KILL, aftype, vuser, NULL);
if(kconf)
return kconf;
}
/* if no_tilde, check the username without tilde against klines too
* -- jilles */
if(user != vuser)
{
kconf = find_conf_by_address(host, sockhost, NULL, ip, CONF_KILL, aftype, vuser, NULL);
if(kconf)
return kconf;
}
return iconf;
}
/* struct ConfItem* find_dline(struct rb_sockaddr_storage*, int)
* Input: An address, an address family.
* Output: The best matching D-line or exempt line.
* Side effects: None.
*/
struct ConfItem *
find_dline(struct sockaddr *addr, int aftype)
{
struct ConfItem *eline;
eline = find_conf_by_address(NULL, NULL, NULL, addr, CONF_EXEMPTDLINE | 1, aftype, NULL, NULL);
if(eline)
return eline;
return find_conf_by_address(NULL, NULL, NULL, addr, CONF_DLINE | 1, aftype, NULL, NULL);
}
/* void find_exact_conf_by_address(const char*, int, const char *)
* Input:
* Output: ConfItem if found
* Side-effects: None
*/
struct ConfItem *
find_exact_conf_by_address(const char *address, int type, const char *username)
{
int masktype, bits;
unsigned long hv;
struct AddressRec *arec;
struct rb_sockaddr_storage addr;
if(address == NULL)
address = "/NOMATCH!/";
masktype = parse_netmask(address, (struct sockaddr *)&addr, &bits);
#ifdef RB_IPV6
if(masktype == HM_IPV6)
{
/* We have to do this, since we do not re-hash for every bit -A1kmm. */
hv = hash_ipv6((struct sockaddr *)&addr, bits - bits % 16);
}
else
#endif
if(masktype == HM_IPV4)
{
/* We have to do this, since we do not re-hash for every bit -A1kmm. */
hv = hash_ipv4((struct sockaddr *)&addr, bits - bits % 8);
}
else
{
hv = get_mask_hash(address);
}
for (arec = atable[hv]; arec; arec = arec->next)
{
if (arec->type == type &&
arec->masktype == masktype &&
(arec->username == NULL || username == NULL ? arec->username == username : !irccmp(arec->username, username)))
{
if (masktype == HM_HOST)
{
if (!irccmp(arec->Mask.hostname, address))
return arec->aconf;
}
else
{
if (arec->Mask.ipa.bits == bits &&
comp_with_mask_sock((struct sockaddr *)&arec->Mask.ipa.addr, (struct sockaddr *)&addr, bits))
return arec->aconf;
}
}
}
return NULL;
}
/* void add_conf_by_address(const char*, int, const char *,
* struct ConfItem *aconf)
* Input:
* Output: None
* Side-effects: Adds this entry to the hash table.
*/
void
add_conf_by_address(const char *address, int type, const char *username, const char *auth_user, struct ConfItem *aconf)
{
static unsigned long prec_value = 0xFFFFFFFF;
int masktype, bits;
unsigned long hv;
struct AddressRec *arec;
if(address == NULL)
address = "/NOMATCH!/";
arec = rb_malloc(sizeof(struct AddressRec));
masktype = parse_netmask(address, (struct sockaddr *)&arec->Mask.ipa.addr, &bits);
arec->Mask.ipa.bits = bits;
arec->masktype = masktype;
#ifdef RB_IPV6
if(masktype == HM_IPV6)
{
/* We have to do this, since we do not re-hash for every bit -A1kmm. */
bits -= bits % 16;
arec->next = atable[(hv = hash_ipv6((struct sockaddr *)&arec->Mask.ipa.addr, bits))];
atable[hv] = arec;
}
else
#endif
if(masktype == HM_IPV4)
{
/* We have to do this, since we do not re-hash for every bit -A1kmm. */
bits -= bits % 8;
arec->next = atable[(hv = hash_ipv4((struct sockaddr *)&arec->Mask.ipa.addr, bits))];
atable[hv] = arec;
}
else
{
arec->Mask.hostname = address;
arec->next = atable[(hv = get_mask_hash(address))];
atable[hv] = arec;
}
arec->username = username;
arec->auth_user = auth_user;
arec->aconf = aconf;
arec->precedence = prec_value--;
arec->type = type;
}
/* void delete_one_address(const char*, struct ConfItem*)
* Input: An address string, the associated ConfItem.
* Output: None
* Side effects: Deletes an address record. Frees the ConfItem if there
* is nothing referencing it, sets it as illegal otherwise.
*/
void
delete_one_address_conf(const char *address, struct ConfItem *aconf)
{
int masktype, bits;
unsigned long hv;
struct AddressRec *arec, *arecl = NULL;
struct rb_sockaddr_storage addr;
masktype = parse_netmask(address, (struct sockaddr *)&addr, &bits);
#ifdef RB_IPV6
if(masktype == HM_IPV6)
{
/* We have to do this, since we do not re-hash for every bit -A1kmm. */
bits -= bits % 16;
hv = hash_ipv6((struct sockaddr *)&addr, bits);
}
else
#endif
if(masktype == HM_IPV4)
{
/* We have to do this, since we do not re-hash for every bit -A1kmm. */
bits -= bits % 8;
hv = hash_ipv4((struct sockaddr *)&addr, bits);
}
else
hv = get_mask_hash(address);
for (arec = atable[hv]; arec; arec = arec->next)
{
if(arec->aconf == aconf)
{
if(arecl)
arecl->next = arec->next;
else
atable[hv] = arec->next;
aconf->status |= CONF_ILLEGAL;
if(!aconf->clients)
free_conf(aconf);
rb_free(arec);
return;
}
arecl = arec;
}
}
/* void clear_out_address_conf(void)
* Input: None
* Output: None
* Side effects: Clears out all address records in the hash table,
* frees them, and frees the ConfItems if nothing references
* them, otherwise sets them as illegal.
*/
void
clear_out_address_conf(void)
{
int i;
struct AddressRec **store_next;
struct AddressRec *arec, *arecn;
for (i = 0; i < ATABLE_SIZE; i++)
{
store_next = &atable[i];
for (arec = atable[i]; arec; arec = arecn)
{
arecn = arec->next;
/* We keep the temporary K-lines and destroy the
* permanent ones, just to be confusing :) -A1kmm */
if(arec->aconf->flags & CONF_FLAGS_TEMPORARY ||
(arec->type != CONF_CLIENT && arec->type != CONF_EXEMPTDLINE))
{
*store_next = arec;
store_next = &arec->next;
}
else
{
arec->aconf->status |= CONF_ILLEGAL;
if(!arec->aconf->clients)
free_conf(arec->aconf);
rb_free(arec);
}
}
*store_next = NULL;
}
}
void
clear_out_address_conf_bans(void)
{
int i;
struct AddressRec **store_next;
struct AddressRec *arec, *arecn;
for (i = 0; i < ATABLE_SIZE; i++)
{
store_next = &atable[i];
for (arec = atable[i]; arec; arec = arecn)
{
arecn = arec->next;
/* We keep the temporary K-lines and destroy the
* permanent ones, just to be confusing :) -A1kmm */
if(arec->aconf->flags & CONF_FLAGS_TEMPORARY ||
(arec->type == CONF_CLIENT || arec->type == CONF_EXEMPTDLINE))
{
*store_next = arec;
store_next = &arec->next;
}
else
{
arec->aconf->status |= CONF_ILLEGAL;
if(!arec->aconf->clients)
free_conf(arec->aconf);
rb_free(arec);
}
}
*store_next = NULL;
}
}
/*
* show_iline_prefix()
*
* inputs - pointer to struct Client requesting output
* - pointer to struct ConfItem
* - name to which iline prefix will be prefixed to
* output - pointer to static string with prefixes listed in ascii form
* side effects - NONE
*/
char *
show_iline_prefix(struct Client *sptr, struct ConfItem *aconf, char *name)
{
static char prefix_of_host[USERLEN + 15];
char *prefix_ptr;
prefix_ptr = prefix_of_host;
if(IsNoTilde(aconf))
*prefix_ptr++ = '-';
if(IsNeedIdentd(aconf))
*prefix_ptr++ = '+';
if(IsConfDoSpoofIp(aconf))
*prefix_ptr++ = '=';
if(IsOper(sptr) && IsConfExemptFlood(aconf))
*prefix_ptr++ = '|';
if(IsOper(sptr) && IsConfExemptDNSBL(aconf) && !IsConfExemptKline(aconf))
*prefix_ptr++ = '$';
if(IsOper(sptr) && IsConfExemptKline(aconf))
*prefix_ptr++ = '^';
if(IsOper(sptr) && IsConfExemptLimits(aconf))
*prefix_ptr++ = '>';
*prefix_ptr = '\0';
strncpy(prefix_ptr, name, USERLEN);
return (prefix_of_host);
}
/* report_auth()
*
* Inputs: pointer to client to report to
* Output: None
* Side effects: Reports configured auth{} blocks to client_p
*/
void
report_auth(struct Client *client_p)
{
char *name, *host, *pass, *user, *classname;
struct AddressRec *arec;
struct ConfItem *aconf;
int i, port;
for (i = 0; i < ATABLE_SIZE; i++)
for (arec = atable[i]; arec; arec = arec->next)
if(arec->type == CONF_CLIENT)
{
aconf = arec->aconf;
if(!IsOper(client_p) && IsConfDoSpoofIp(aconf))
continue;
get_printable_conf(aconf, &name, &host, &pass, &user, &port,
&classname);
if(!EmptyString(aconf->spasswd))
pass = aconf->spasswd;
sendto_one_numeric(client_p, RPL_STATSILINE,
form_str(RPL_STATSILINE),
name, pass, show_iline_prefix(client_p, aconf, user),
show_ip_conf(aconf, client_p) ? host : "255.255.255.255",
port, classname);
}
}
/* report_Klines()
*
* inputs - Client to report to, mask
* outputs -
* side effects - Reports configured K-lines to client_p.
*/
void
report_Klines(struct Client *source_p)
{
char *host, *pass, *user, *oper_reason;
struct AddressRec *arec;
struct ConfItem *aconf = NULL;
int i;
for (i = 0; i < ATABLE_SIZE; i++)
{
for (arec = atable[i]; arec; arec = arec->next)
{
if(arec->type == CONF_KILL)
{
aconf = arec->aconf;
/* its a tempkline, theyre reported elsewhere */
if(aconf->flags & CONF_FLAGS_TEMPORARY)
continue;
get_printable_kline(source_p, aconf, &host, &pass, &user, &oper_reason);
sendto_one_numeric(source_p, RPL_STATSKLINE,
form_str(RPL_STATSKLINE),
'K', host, user, pass,
oper_reason ? "|" : "",
oper_reason ? oper_reason : "");
}
}
}
}