-/*
- Copyright (C) Andrew Tridgell 1998
-
- 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., 675 Mass Ave, Cambridge, MA 02139, USA.
-*/
-
/*
- hosts allow/deny code for rsync
-
- */
+ * Routines to authenticate access to a daemon (hosts allow/deny).
+ *
+ * Copyright (C) 1998 Andrew Tridgell
+ * Copyright (C) 2004-2022 Wayne Davison
+ *
+ * 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 3 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, visit the http://fsf.org website.
+ */
#include "rsync.h"
+#include "ifuncs.h"
+#ifdef HAVE_NETGROUP_H
+#include <netgroup.h>
+#endif
+static int allow_forward_dns;
-static int match_hostname(char *host, char *tok)
+extern const char undetermined_hostname[];
+
+static int match_hostname(const char **host_ptr, const char *addr, const char *tok)
{
- if (!host || !*host) return 0;
- return (fnmatch(tok, host, 0) == 0);
+ struct hostent *hp;
+ unsigned int i;
+ const char *host = *host_ptr;
+
+ if (!host || !*host)
+ return 0;
+
+#ifdef HAVE_INNETGR
+ if (*tok == '@' && tok[1])
+ return innetgr(tok + 1, host, NULL, NULL);
+#endif
+
+ /* First check if the reverse-DNS-determined hostname matches. */
+ if (iwildmatch(tok, host))
+ return 1;
+
+ if (!allow_forward_dns)
+ return 0;
+
+ /* Fail quietly if tok is an address or wildcarded entry, not a simple hostname. */
+ if (!tok[strspn(tok, ".0123456789")] || tok[strcspn(tok, ":/*?[")])
+ return 0;
+
+ /* Now try forward-DNS on the token (config-specified hostname) and see if the IP matches. */
+ if (!(hp = gethostbyname(tok)))
+ return 0;
+
+ for (i = 0; hp->h_addr_list[i] != NULL; i++) {
+ if (strcmp(addr, inet_ntoa(*(struct in_addr*)(hp->h_addr_list[i]))) == 0) {
+ /* If reverse lookups are off, we'll use the conf-specified
+ * hostname in preference to UNDETERMINED. */
+ if (host == undetermined_hostname)
+ *host_ptr = strdup(tok);
+ return 1;
+ }
+ }
+
+ return 0;
}
-static int match_binary(char *b1, char *b2, char *mask, int addrlen)
+static int match_binary(const char *b1, const char *b2, const char *mask, int addrlen)
{
int i;
- for (i=0; i<addrlen; i++) {
- if ((b1[i]^b2[i])&mask[i]) {
+ for (i = 0; i < addrlen; i++) {
+ if ((b1[i] ^ b2[i]) & mask[i])
return 0;
- }
}
return 1;
}
-static void make_mask(char *mask, int plen, int addrlen) {
+static void make_mask(char *mask, int plen, int addrlen)
+{
int w, b;
w = plen >> 3;
if (w)
memset(mask, 0xff, w);
- mask[w] = 0xff & (0xff<<(8-b));
+ if (w < addrlen)
+ mask[w] = 0xff & (0xff<<(8-b));
if (w+1 < addrlen)
memset(mask+w+1, 0, addrlen-w-1);
return;
}
-static int match_address(char *addr, char *tok)
+static int match_address(const char *addr, const char *tok)
{
char *p;
struct addrinfo hints, *resa, *rest;
char mask[16];
char *a = NULL, *t = NULL;
- if (!addr || !*addr) return 0;
+ if (!addr || !*addr)
+ return 0;
p = strchr(tok,'/');
- if (p) *p = 0;
+ if (p)
+ *p = '\0';
+
+ /* Fail quietly if tok is a hostname, not an address. */
+ if (tok[strspn(tok, ".0123456789")] && strchr(tok, ':') == NULL) {
+ if (p)
+ *p = '/';
+ return 0;
+ }
memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_flags = AI_NUMERICHOST;
#endif
- gai = getaddrinfo(addr, NULL, &hints, &resa);
- if (gai) return 0;
+ if (getaddrinfo(addr, NULL, &hints, &resa) != 0) {
+ if (p)
+ *p = '/';
+ return 0;
+ }
gai = getaddrinfo(tok, NULL, &hints, &rest);
if (p)
*p++ = '/';
- if (gai) {
- rprintf(FERROR,"malformed address %s\n", tok);
+ if (gai != 0) {
+ rprintf(FLOG, "error matching address %s: %s\n",
+ tok, gai_strerror(gai));
freeaddrinfo(resa);
return 0;
}
break;
#ifdef INET6
- case PF_INET6:
- {
+ case PF_INET6: {
struct sockaddr_in6 *sin6a, *sin6t;
sin6a = (struct sockaddr_in6 *)resa->ai_addr;
a = (char *)&sin6a->sin6_addr;
t = (char *)&sin6t->sin6_addr;
+ addrlen = 16;
+
#ifdef HAVE_SOCKADDR_IN6_SCOPE_ID
- if (sin6t->sin6_scope_id &&
- sin6a->sin6_scope_id != sin6t->sin6_scope_id) {
+ if (sin6t->sin6_scope_id && sin6a->sin6_scope_id != sin6t->sin6_scope_id) {
ret = 0;
goto out;
}
#endif
- a = (char *)&sin6a->sin6_addr;
- t = (char *)&sin6t->sin6_addr;
- addrlen = 16;
-
break;
- }
+ }
#endif
default:
- rprintf(FERROR,"unknown family %u\n", rest->ai_family);
- ret = 0;
- goto out;
+ rprintf(FLOG, "unknown family %u\n", rest->ai_family);
+ ret = 0;
+ goto out;
}
bits = -1;
#ifdef HAVE_STRTOL
bits = strtol(p, &ep, 10);
if (!*p || *ep) {
- rprintf(FERROR,"malformed mask in %s\n", tok);
+ rprintf(FLOG, "malformed mask in %s\n", tok);
ret = 0;
goto out;
}
#else
for (pp = (unsigned char *)p; *pp; pp++) {
if (!isascii(*pp) || !isdigit(*pp)) {
- rprintf(FERROR,"malformed mask in %s\n", tok);
+ rprintf(FLOG, "malformed mask in %s\n", tok);
ret = 0;
goto out;
}
goto out;
}
if (bits < 0 || bits > (addrlen << 3)) {
- rprintf(FERROR,"malformed mask in %s\n", tok);
+ rprintf(FLOG, "malformed mask in %s\n", tok);
ret = 0;
goto out;
}
ret = match_binary(a, t, mask, addrlen);
-out:
+ out:
freeaddrinfo(resa);
freeaddrinfo(rest);
return ret;
}
-static int access_match(char *list, char *addr, char *host)
+static int access_match(const char *list, const char *addr, const char **host_ptr)
{
char *tok;
char *list2 = strdup(list);
- if (!list2) out_of_memory("access_match");
-
strlower(list2);
- if (host) strlower(host);
- for (tok=strtok(list2," ,\t"); tok; tok=strtok(NULL," ,\t")) {
- if (match_hostname(host, tok) || match_address(addr, tok)) {
+ for (tok = strtok(list2, " ,\t"); tok; tok = strtok(NULL, " ,\t")) {
+ if (match_hostname(host_ptr, addr, tok) || match_address(addr, tok)) {
free(list2);
return 1;
}
return 0;
}
-int allow_access(char *addr, char *host, char *allow_list, char *deny_list)
+int allow_access(const char *addr, const char **host_ptr, int i)
{
- /* if theres no deny list and no allow list then allow access */
- if ((!deny_list || !*deny_list) && (!allow_list || !*allow_list))
- return 1;
+ const char *allow_list = lp_hosts_allow(i);
+ const char *deny_list = lp_hosts_deny(i);
- /* if there is an allow list but no deny list then allow only hosts
- on the allow list */
- if (!deny_list || !*deny_list)
- return(access_match(allow_list, addr, host));
+ if (allow_list && !*allow_list)
+ allow_list = NULL;
+ if (deny_list && !*deny_list)
+ deny_list = NULL;
- /* if theres a deny list but no allow list then allow
- all hosts not on the deny list */
- if (!allow_list || !*allow_list)
- return(!access_match(deny_list,addr,host));
+ allow_forward_dns = lp_forward_lookup(i);
- /* if there are both type of list then allow all hosts on the
- allow list */
- if (access_match(allow_list,addr,host))
- return 1;
+ /* If we match an allow-list item, we always allow access. */
+ if (allow_list) {
+ if (access_match(allow_list, addr, host_ptr))
+ return 1;
+ /* For an allow-list w/o a deny-list, disallow non-matches. */
+ if (!deny_list)
+ return 0;
+ }
- /* if there are both type of list and it's not on the allow then
- allow it if its not on the deny */
- if (access_match(deny_list,addr,host))
+ /* If we match a deny-list item (and got past any allow-list
+ * items), we always disallow access. */
+ if (deny_list && access_match(deny_list, addr, host_ptr))
return 0;
+ /* Allow all other access. */
return 1;
}