2 This module is an adaption of code from the tcpd-1.4 package written
3 by Wietse Venema, Eindhoven University of Technology, The Netherlands.
5 The code is used here with permission.
7 The code has been considerably changed from the original. Bug reports
8 should be sent to samba@samba.org
10 Updated for IPv6 by Jeremy Allison (C) 2007.
18 /* masked_match - match address against netnumber/netmask */
19 static bool masked_match(const char *tok, const char *slash, const char *s)
21 struct sockaddr_storage ss_mask;
22 struct sockaddr_storage ss_tok;
23 struct sockaddr_storage ss_host;
24 char *tok_copy = NULL;
26 if (!interpret_string_addr(&ss_host, s, 0)) {
31 /* IPv6 address - remove braces. */
32 tok_copy = SMB_STRDUP(tok+1);
36 /* Remove the terminating ']' */
37 tok_copy[PTR_DIFF(slash,tok)-1] = '\0';
39 tok_copy = SMB_STRDUP(tok);
43 /* Remove the terminating '/' */
44 tok_copy[PTR_DIFF(slash,tok)] = '\0';
47 if (!interpret_string_addr(&ss_tok, tok_copy, 0)) {
54 if (strlen(slash + 1) > 2) {
55 if (!interpret_string_addr(&ss_mask, slash+1, 0)) {
60 unsigned long val = strtoul(slash+1, &endp, 0);
61 if (slash+1 == endp || (endp && *endp != '\0')) {
64 if (!make_netmask(&ss_mask, &ss_tok, val)) {
69 return same_net(&ss_host, &ss_tok, &ss_mask);
72 /* string_match - match string s against token tok */
73 static bool string_match(const char *tok,const char *s)
79 /* Return true if a token has the magic value "ALL". Return
80 * true if the token is "FAIL". If the token starts with a "."
81 * (domain name), return true if it matches the last fields of
82 * the string. If the token has the magic value "LOCAL",
83 * return true if the string does not contain a "."
84 * character. If the token ends on a "." (network number),
85 * return true if it matches the first fields of the
86 * string. If the token begins with a "@" (netgroup name),
87 * return true if the string is a (host) member of the
88 * netgroup. Return true if the token fully matches the
89 * string. If the token is a netnumber/netmask pair, return
90 * true if the address is a member of the specified subnet.
93 if (tok[0] == '.') { /* domain: match last fields */
94 if ((str_len = strlen(s)) > (tok_len = strlen(tok))
95 && strequal(tok, s + str_len - tok_len)) {
98 } else if (tok[0] == '@') { /* netgroup: look it up */
101 char *mydomain = NULL;
102 char *hostname = NULL;
103 bool netgroup_ok = false;
106 NULL, SINGLETON_CACHE,
107 data_blob_string_const("yp_default_domain"),
110 SMB_ASSERT(tmp.length > 0);
111 mydomain = (tmp.data[0] == '\0')
112 ? NULL : (char *)tmp.data;
115 yp_get_default_domain(&mydomain);
118 NULL, SINGLETON_CACHE,
119 data_blob_string_const("yp_default_domain"),
120 data_blob_string_const(mydomain?mydomain:""));
124 DEBUG(0,("Unable to get default yp domain. "
125 "Try without it.\n"));
127 if (!(hostname = SMB_STRDUP(s))) {
128 DEBUG(1,("out of memory for strdup!\n"));
132 netgroup_ok = innetgr(tok + 1, hostname, (char *) 0, mydomain);
134 DEBUG(5,("looking for %s of domain %s in netgroup %s gave %s\n",
136 mydomain?mydomain:"(ANY)",
138 BOOLSTR(netgroup_ok)));
145 DEBUG(0,("access: netgroup support is not configured\n"));
148 } else if (strequal(tok, "ALL")) { /* all: match any */
150 } else if (strequal(tok, "FAIL")) { /* fail: match any */
152 } else if (strequal(tok, "LOCAL")) { /* local: no dots */
153 if (strchr_m(s, '.') == 0 && !strequal(s, "unknown")) {
156 } else if (strequal(tok, s)) { /* match host name or address */
158 } else if (tok[(tok_len = strlen(tok)) - 1] == '.') { /* network */
159 if (strncmp(tok, s, tok_len) == 0) {
162 } else if ((cut = strchr_m(tok, '/')) != 0) { /* netnumber/netmask */
163 if ((isdigit(s[0]) && strchr_m(tok, '.') != NULL) ||
164 (tok[0] == '[' && cut > tok && cut[-1] == ']') ||
165 ((isxdigit(s[0]) || s[0] == ':') &&
166 strchr_m(tok, ':') != NULL)) {
168 * [IPv6:addr]/netmask or IPv6:addr/netmask */
169 return masked_match(tok, cut, s);
171 } else if (strchr_m(tok, '*') != 0 || strchr_m(tok, '?')) {
172 return unix_wild_match(tok, s);
177 /* client_match - match host name and address against token */
178 static bool client_match(const char *tok, const void *item)
180 const char **client = (const char **)item;
184 * Try to match the address first. If that fails, try to match the host
188 if ((match = string_match(tok, client[ADDR_INDEX])) == false) {
189 if (client[NAME_INDEX][0] != 0) {
190 match = string_match(tok, client[NAME_INDEX]);
197 /* list_match - match an item against a list of tokens with exceptions */
198 static bool list_match(const char **list,const void *item,
199 bool (*match_fn)(const char *, const void *))
208 * Process tokens one at a time. We have exhausted all possible matches
209 * when we reach an "EXCEPT" token or the end of the list. If we do find
210 * a match, look for an "EXCEPT" list and recurse to determine whether
211 * the match is affected by any exceptions.
214 for (; *list ; list++) {
215 if (strequal(*list, "EXCEPT")) {
216 /* EXCEPT: give up */
219 if ((match = (*match_fn) (*list, item))) {
224 /* Process exceptions to true or FAIL matches. */
226 if (match != false) {
227 while (*list && !strequal(*list, "EXCEPT")) {
231 for (; *list; list++) {
232 if ((*match_fn) (*list, item)) {
233 /* Exception Found */
242 /* return true if access should be allowed */
243 static bool allow_access_internal(const char **deny_list,
244 const char **allow_list,
248 const char *client[2];
250 client[NAME_INDEX] = cname;
251 client[ADDR_INDEX] = caddr;
253 /* if it is loopback then always allow unless specifically denied */
254 if (strcmp(caddr, "127.0.0.1") == 0 || strcmp(caddr, "::1") == 0) {
256 * If 127.0.0.1 matches both allow and deny then allow.
257 * Patch from Steve Langasek vorlon@netexpress.net.
260 list_match(deny_list,client,client_match) &&
262 !list_match(allow_list,client, client_match))) {
268 /* if theres no deny list and no allow list then allow access */
269 if ((!deny_list || *deny_list == 0) &&
270 (!allow_list || *allow_list == 0)) {
274 /* if there is an allow list but no deny list then allow only hosts
276 if (!deny_list || *deny_list == 0) {
277 return(list_match(allow_list,client,client_match));
280 /* if theres a deny list but no allow list then allow
281 all hosts not on the deny list */
282 if (!allow_list || *allow_list == 0) {
283 return(!list_match(deny_list,client,client_match));
286 /* if there are both types of list then allow all hosts on the
288 if (list_match(allow_list,(const char *)client,client_match)) {
292 /* if there are both types of list and it's not on the allow then
293 allow it if its not on the deny */
294 if (list_match(deny_list,(const char *)client,client_match)) {
301 /* return true if access should be allowed */
302 bool allow_access(const char **deny_list,
303 const char **allow_list,
308 char *nc_cname = smb_xstrdup(cname);
309 char *nc_caddr = smb_xstrdup(caddr);
311 ret = allow_access_internal(deny_list, allow_list, nc_cname, nc_caddr);
318 /* return true if the char* contains ip addrs only. Used to avoid
321 static bool only_ipaddrs_in_list(const char **list)
329 for (; *list ; list++) {
330 /* factor out the special strings */
331 if (strequal(*list, "ALL") || strequal(*list, "FAIL") ||
332 strequal(*list, "EXCEPT")) {
336 if (!is_ipaddress(*list)) {
338 * If we failed, make sure that it was not because
339 * the token was a network/netmask pair. Only
340 * network/netmask pairs have a '/' in them.
342 if ((strchr_m(*list, '/')) == NULL) {
344 DEBUG(3,("only_ipaddrs_in_list: list has "
345 "non-ip address (%s)\n",
355 /* return true if access should be allowed to a service for a socket */
356 bool check_access(int sock, const char **allow_list, const char **deny_list)
359 bool only_ip = false;
361 if ((!deny_list || *deny_list==0) && (!allow_list || *allow_list==0))
365 char addr[INET6_ADDRSTRLEN];
367 /* Bypass name resolution calls if the lists
368 * only contain IP addrs */
369 if (only_ipaddrs_in_list(allow_list) &&
370 only_ipaddrs_in_list(deny_list)) {
372 DEBUG (3, ("check_access: no hostnames "
373 "in host allow/deny list.\n"));
374 ret = allow_access(deny_list,
377 get_peer_addr(sock,addr,sizeof(addr)));
379 DEBUG (3, ("check_access: hostnames in "
380 "host allow/deny list.\n"));
381 ret = allow_access(deny_list,
383 get_peer_name(sock,true),
384 get_peer_addr(sock,addr,sizeof(addr)));
388 DEBUG(2,("Allowed connection from %s (%s)\n",
389 only_ip ? "" : get_peer_name(sock,true),
390 get_peer_addr(sock,addr,sizeof(addr))));
392 DEBUG(0,("Denied connection from %s (%s)\n",
393 only_ip ? "" : get_peer_name(sock,true),
394 get_peer_addr(sock,addr,sizeof(addr))));