/*
-This module is an adaption of code from the tcpd-1.4 package written
-by Wietse Venema, Eindhoven University of Technology, The Netherlands.
+ This module is an adaption of code from the tcpd-1.4 package written
+ by Wietse Venema, Eindhoven University of Technology, The Netherlands.
-The code is used here with permission.
+ The code is used here with permission.
-The code has been considerably changed from the original. Bug reports
-should be sent to samba-bugs@samba.anu.edu.au
+ The code has been considerably changed from the original. Bug reports
+ should be sent to samba@samba.org
*/
#include "includes.h"
-#define ALLOW_PURE_ADDRESSES
-
-extern int DEBUGLEVEL;
-
-#ifndef INADDR_NONE
-#define INADDR_NONE ((unsigned long)~0)
-#endif
-
-
-#define FROM_ADDRLEN (4*3+3+1)
-#define Good True
-#define Bad False
-
-#define CLIENT_MATCH client_match
-
-/* Delimiters for lists of daemons or clients. */
-
-static char sep[] = ", \t";
-
-/* Constants to be used in assignments only, not in comparisons... */
-
-#define YES 1
-#define NO 0
#define FAIL (-1)
-/* Forward declarations. */
-static int list_match(char *list,char *item, int (*match_fn)());
-static int client_match(char *tok,char *item);
-static int string_match(char *tok,char *s);
-static int masked_match(char *tok, char *slash, char *s);
-static int matchname(char *remotehost,struct in_addr addr);
+#define ALLONES ((uint32)0xFFFFFFFF)
-/* Size of logical line buffer. */
-#define BUFLEN 2048
-
-
-/* return true if access should be allowed to a service*/
-BOOL check_access(int snum)
+/* masked_match - match address against netnumber/netmask */
+static BOOL masked_match(const char *tok, const char *slash, const char *s)
{
- extern int Client;
- extern struct from_host Client_info;
- char *denyl,*allowl;
- BOOL ret = False;
-
- denyl = lp_hostsdeny(snum);
- if (denyl) denyl = strdup(denyl);
-
- allowl = lp_hostsallow(snum);
- if (allowl) allowl = strdup(allowl);
-
-
- fromhost(Client,&Client_info);
-
- if ((!denyl || *denyl==0) && (!allowl || *allowl==0))
- ret = True;
-
- if (!ret)
- {
- if (!fromhost(Client,&Client_info))
- DEBUG(0,("ERROR: Can't get from_host info\n"));
- else
- {
- if (allow_access(denyl,allowl,&Client_info))
- {
- if (snum >= 0)
- DEBUG(2,("Allowed connection from %s (%s) to %s\n",
- Client_info.name,Client_info.addr,
- lp_servicename(snum)));
- ret = True;
- }
- else
- if (snum >= 0)
- DEBUG(0,("Denied connection from %s (%s) to %s\n",
- Client_info.name,Client_info.addr,
- lp_servicename(snum)));
+ uint32 net;
+ uint32 mask;
+ uint32 addr;
+ fstring tok_cpy;
+
+ if ((addr = interpret_addr(s)) == INADDR_NONE)
+ return (False);
+
+ fstrcpy(tok_cpy, tok);
+ tok_cpy[PTR_DIFF(slash,tok)] = '\0';
+ net = interpret_addr(tok_cpy);
+ tok_cpy[PTR_DIFF(slash,tok)] = '/';
+
+ if (strlen(slash + 1) > 2) {
+ mask = interpret_addr(slash + 1);
+ } else {
+ mask = (uint32)((ALLONES >> atoi(slash + 1)) ^ ALLONES);
+ /* convert to network byte order */
+ mask = htonl(mask);
+ }
+
+ if (net == INADDR_NONE || mask == INADDR_NONE) {
+ DEBUG(0,("access: bad net/mask access control: %s\n", tok));
+ return (False);
}
- }
-
- if (denyl) free(denyl);
- if (allowl) free(allowl);
- return(ret);
+
+ return ((addr & mask) == net);
}
+/* string_match - match string against token */
+static BOOL string_match(const char *tok,const char *s, char *invalid_char)
+{
+ size_t tok_len;
+ size_t str_len;
+ const char *cut;
+
+ *invalid_char = '\0';
+
+ /* Return True if a token has the magic value "ALL". Return
+ * FAIL if the token is "FAIL". If the token starts with a "."
+ * (domain name), return True if it matches the last fields of
+ * the string. If the token has the magic value "LOCAL",
+ * return True if the string does not contain a "."
+ * character. If the token ends on a "." (network number),
+ * return True if it matches the first fields of the
+ * string. If the token begins with a "@" (netgroup name),
+ * return True if the string is a (host) member of the
+ * netgroup. Return True if the token fully matches the
+ * string. If the token is a netnumber/netmask pair, return
+ * True if the address is a member of the specified subnet.
+ */
+
+ if (tok[0] == '.') { /* domain: match last fields */
+ if ((str_len = strlen(s)) > (tok_len = strlen(tok))
+ && strcasecmp(tok, s + str_len - tok_len) == 0)
+ return (True);
+ } else if (tok[0] == '@') { /* netgroup: look it up */
+#ifdef HAVE_NETGROUP
+ static char *mydomain = NULL;
+ char *hostname = NULL;
+ BOOL netgroup_ok = False;
+
+ if (!mydomain)
+ yp_get_default_domain(&mydomain);
+
+ if (!mydomain) {
+ DEBUG(0,("Unable to get default yp domain.\n"));
+ return False;
+ }
+ if (!(hostname = strdup(s))) {
+ DEBUG(1,("out of memory for strdup!\n"));
+ return False;
+ }
+
+ netgroup_ok = innetgr(tok + 1, hostname, (char *) 0, mydomain);
+
+ DEBUG(5,("looking for %s of domain %s in netgroup %s gave %s\n",
+ hostname,
+ mydomain,
+ tok+1,
+ BOOLSTR(netgroup_ok)));
+
+ SAFE_FREE(hostname);
+
+ if (netgroup_ok)
+ return(True);
+#else
+ DEBUG(0,("access: netgroup support is not configured\n"));
+ return (False);
+#endif
+ } else if (strcasecmp(tok, "ALL") == 0) { /* all: match any */
+ return (True);
+ } else if (strcasecmp(tok, "FAIL") == 0) { /* fail: match any */
+ return (FAIL);
+ } else if (strcasecmp(tok, "LOCAL") == 0) { /* local: no dots */
+ if (strchr_m(s, '.') == 0 && strcasecmp(s, "unknown") != 0)
+ return (True);
+ } else if (!strcasecmp(tok, s)) { /* match host name or address */
+ return (True);
+ } else if (tok[(tok_len = strlen(tok)) - 1] == '.') { /* network */
+ if (strncmp(tok, s, tok_len) == 0)
+ return (True);
+ } else if ((cut = strchr_m(tok, '/')) != 0) { /* netnumber/netmask */
+ if (isdigit((int)s[0]) && masked_match(tok, cut, s))
+ return (True);
+ } else if (strchr_m(tok, '*') != 0) {
+ *invalid_char = '*';
+ } else if (strchr_m(tok, '?') != 0) {
+ *invalid_char = '?';
+ }
+ return (False);
+}
-/* return true if access should be allowed */
-BOOL allow_access(char *deny_list,char *allow_list,struct from_host *client)
+/* client_match - match host name and address against token */
+static BOOL client_match(const char *tok, const char *item)
{
- /* if theres no deny list and no allow list then allow access */
- if ((!deny_list || *deny_list == 0) && (!allow_list || *allow_list == 0))
- return(True);
-
- /* if there is an allow list but no deny list then allow only hosts
- on the allow list */
- if (!deny_list || *deny_list == 0)
- return(list_match(allow_list,(char *)client,CLIENT_MATCH));
-
- /* if theres a deny list but no allow list then allow
- all hosts not on the deny list */
- if (!allow_list || *allow_list == 0)
- return(!list_match(deny_list,(char *)client,CLIENT_MATCH));
-
- /* if there are both type of list then allow all hosts on the allow list */
- if (list_match(allow_list,(char *)client,CLIENT_MATCH))
- return (True);
-
- /* if there are both type of list and it's not on the allow then
- allow it if its not on the deny */
- if (list_match(deny_list,(char *)client,CLIENT_MATCH))
- return (False);
-
- return (True);
+ const char **client = (const char **)item;
+ BOOL match;
+ char invalid_char = '\0';
+
+ /*
+ * Try to match the address first. If that fails, try to match the host
+ * name if available.
+ */
+
+ if ((match = string_match(tok, client[1], &invalid_char)) == 0) {
+ if(invalid_char)
+ DEBUG(0,("client_match: address match failing due to invalid character '%c' found in \
+token '%s' in an allow/deny hosts line.\n", invalid_char, tok ));
+
+ if (client[0][0] != 0)
+ match = string_match(tok, client[0], &invalid_char);
+
+ if(invalid_char)
+ DEBUG(0,("client_match: address match failing due to invalid character '%c' found in \
+token '%s' in an allow/deny hosts line.\n", invalid_char, tok ));
+ }
+
+ return (match);
}
/* list_match - match an item against a list of tokens with exceptions */
-/* (All modifications are marked with the initials "jkf") */
-static int list_match(char *list,char *item, int (*match_fn)())
+static BOOL list_match(const char **list,const char *item,
+ BOOL (*match_fn)(const char *, const char *))
{
- char *tok;
- char *listcopy; /* jkf */
- int match = NO;
-
- /*
- * jkf@soton.ac.uk -- 31 August 1994 -- Stop list_match()
- * overwriting the list given as its first parameter.
- */
-
- /* jkf -- can get called recursively with NULL list */
- listcopy = (list == 0) ? (char *)0 : strdup(list);
-
- /*
- * Process tokens one at a time. We have exhausted all possible matches
- * when we reach an "EXCEPT" token or the end of the list. If we do find
- * a match, look for an "EXCEPT" list and recurse to determine whether
- * the match is affected by any exceptions.
- */
-
- for (tok = strtok(listcopy, sep); tok ; tok = strtok(NULL, sep)) {
- if (strcasecmp(tok, "EXCEPT") == 0) /* EXCEPT: give up */
- break;
- if ((match = (*match_fn) (tok, item))) /* YES or FAIL */
- break;
- }
- /* Process exceptions to YES or FAIL matches. */
-
- if (match != NO) {
- while ((tok = strtok((char *) 0, sep)) && strcasecmp(tok, "EXCEPT"))
- /* VOID */ ;
- if (tok == 0 || list_match((char *) 0, item, match_fn) == NO) {
- if (listcopy != 0) free(listcopy); /* jkf */
- return (match);
+ BOOL match = False;
+
+ if (!list)
+ return False;
+
+ /*
+ * Process tokens one at a time. We have exhausted all possible matches
+ * when we reach an "EXCEPT" token or the end of the list. If we do find
+ * a match, look for an "EXCEPT" list and recurse to determine whether
+ * the match is affected by any exceptions.
+ */
+
+ for (; *list ; list++) {
+ if (strcasecmp(*list, "EXCEPT") == 0) /* EXCEPT: give up */
+ break;
+ if ((match = (*match_fn) (*list, item))) /* True or FAIL */
+ break;
}
- }
+ /* Process exceptions to True or FAIL matches. */
- if (listcopy != 0) free(listcopy); /* jkf */
- return (NO);
-}
+ if (match != False) {
+ while (*list && strcasecmp(*list, "EXCEPT"))
+ list++;
+ for (; *list; list++) {
+ if ((*match_fn) (*list, item)) /* Exception Found */
+ return False;
+ }
+ }
-/* client_match - match host name and address against token */
-static int client_match(char *tok,char *item)
-{
- struct from_host *client = (struct from_host *) item;
- int match;
-
- /*
- * Try to match the address first. If that fails, try to match the host
- * name if available.
- */
-
- if ((match = string_match(tok, client->addr)) == 0)
- if (client->name[0] != 0)
- match = string_match(tok, client->name);
- return (match);
+ return (match);
}
-/* string_match - match string against token */
-static int string_match(char *tok,char *s)
+/* return true if access should be allowed */
+static BOOL allow_access_internal(const char **deny_list,const char **allow_list,
+ const char *cname, const char *caddr)
{
- int tok_len;
- int str_len;
- char *cut;
-
- /*
- * Return YES if a token has the magic value "ALL". Return FAIL if the
- * token is "FAIL". If the token starts with a "." (domain name), return
- * YES if it matches the last fields of the string. If the token has the
- * magic value "LOCAL", return YES if the string does not contain a "."
- * character. If the token ends on a "." (network number), return YES if
- * it matches the first fields of the string. If the token begins with a
- * "@" (netgroup name), return YES if the string is a (host) member of
- * the netgroup. Return YES if the token fully matches the string. If the
- * token is a netnumber/netmask pair, return YES if the address is a
- * member of the specified subnet.
- */
-
- if (tok[0] == '.') { /* domain: match last fields */
- if ((str_len = strlen(s)) > (tok_len = strlen(tok))
- && strcasecmp(tok, s + str_len - tok_len) == 0)
- return (YES);
- } else if (tok[0] == '@') { /* netgroup: look it up */
-#ifdef NETGROUP
- static char *mydomain = NULL;
- char *hostname = NULL;
- BOOL netgroup_ok = False;
-
- if (!mydomain) yp_get_default_domain(&mydomain);
-
- if (!(hostname = strdup(s))) {
- DEBUG(1,("out of memory for strdup!\n"));
- return NO;
- }
-
- netgroup_ok = innetgr(tok + 1, hostname, (char *) 0, mydomain);
-
- DEBUG(5,("looking for %s of domain %s in netgroup %s gave %s\n",
- hostname,
- mydomain,
- tok+1,
- BOOLSTR(netgroup_ok)));
-
-#ifdef NETGROUP_INSECURE
- /* if you really want netgroups that match non qualified names
- then define NETGROUP_INSECURE. It can, however, be a big
- security hole */
- {
- char *clnt_domain;
- if (!netgroup_ok && (clnt_domain=strchr(hostname,'.'))) {
- *clnt_domain++ = '\0';
- netgroup_ok = innetgr(tok + 1, hostname, (char *) 0, mydomain);
+ const char *client[2];
+
+ client[0] = cname;
+ client[1] = caddr;
+
+ /* if it is loopback then always allow unless specifically denied */
+ if (strcmp(caddr, "127.0.0.1") == 0) {
+ /*
+ * If 127.0.0.1 matches both allow and deny then allow.
+ * Patch from Steve Langasek vorlon@netexpress.net.
+ */
+ if (deny_list &&
+ list_match(deny_list,(const char *)client,client_match) &&
+ (!allow_list ||
+ !list_match(allow_list,(const char *)client, client_match))) {
+ return False;
+ }
+ return True;
}
- }
-#endif
- free(hostname);
-
- if (netgroup_ok) return(YES);
-#else
- DEBUG(0,("access: netgroup support is not configured"));
- return (NO);
-#endif
- } else if (strcasecmp(tok, "ALL") == 0) { /* all: match any */
- return (YES);
- } else if (strcasecmp(tok, "FAIL") == 0) { /* fail: match any */
- return (FAIL);
- } else if (strcasecmp(tok, "LOCAL") == 0) { /* local: no dots */
- if (strchr(s, '.') == 0 && strcasecmp(s, "unknown") != 0)
- return (YES);
- } else if (!strcasecmp(tok, s)) { /* match host name or address */
- return (YES);
- } else if (tok[(tok_len = strlen(tok)) - 1] == '.') { /* network */
- if (strncmp(tok, s, tok_len) == 0)
- return (YES);
- } else if ((cut = strchr(tok, '/')) != 0) { /* netnumber/netmask */
- if (isdigit(s[0]) && masked_match(tok, cut, s))
- return (YES);
- }
- return (NO);
+ /* if theres no deny list and no allow list then allow access */
+ if ((!deny_list || *deny_list == 0) &&
+ (!allow_list || *allow_list == 0)) {
+ return(True);
+ }
+
+ /* if there is an allow list but no deny list then allow only hosts
+ on the allow list */
+ if (!deny_list || *deny_list == 0)
+ return(list_match(allow_list,(const char *)client,client_match));
+
+ /* if theres a deny list but no allow list then allow
+ all hosts not on the deny list */
+ if (!allow_list || *allow_list == 0)
+ return(!list_match(deny_list,(const char *)client,client_match));
+
+ /* if there are both types of list then allow all hosts on the
+ allow list */
+ if (list_match(allow_list,(const char *)client,client_match))
+ return (True);
+
+ /* if there are both types of list and it's not on the allow then
+ allow it if its not on the deny */
+ if (list_match(deny_list,(const char *)client,client_match))
+ return (False);
+
+ return (True);
}
-/* masked_match - match address against netnumber/netmask */
-static int masked_match(char *tok, char *slash, char *s)
+/* return true if access should be allowed */
+BOOL allow_access(const char **deny_list, const char **allow_list,
+ const char *cname, const char *caddr)
{
- uint32 net;
- uint32 mask;
- uint32 addr;
-
- if ((addr = interpret_addr(s)) == INADDR_NONE)
- return (NO);
- *slash = 0;
- net = interpret_addr(tok);
- *slash = '/';
- if (net == INADDR_NONE || (mask = interpret_addr(slash + 1)) == INADDR_NONE) {
- DEBUG(0,("access: bad net/mask access control: %s", tok));
- return (NO);
- }
- return ((addr & mask) == net);
+ BOOL ret;
+ char *nc_cname = smb_xstrdup(cname);
+ char *nc_caddr = smb_xstrdup(caddr);
+
+ ret = allow_access_internal(deny_list, allow_list, nc_cname, nc_caddr);
+
+ SAFE_FREE(nc_cname);
+ SAFE_FREE(nc_caddr);
+ return ret;
}
+/* return true if the char* contains ip addrs only. Used to avoid
+gethostbyaddr() calls */
-/* fromhost - find out what is at the other end of a socket */
-BOOL fromhost(int sock,struct from_host *f)
+static BOOL only_ipaddrs_in_list(const char** list)
{
- static struct sockaddr sa;
- struct sockaddr_in *sockin = (struct sockaddr_in *) (&sa);
- struct hostent *hp;
- int length = sizeof(sa);
- static char addr_buf[FROM_ADDRLEN];
- static char name_buf[MAXHOSTNAMELEN];
- BOOL takeAddressAsHostname = False;
-
- if (getpeername(sock, &sa, &length) < 0)
- {
- DEBUG(0,("getpeername failed\n"));
- return(False);
- }
-
- f->sin = sockin;
- f->addr = strcpy(addr_buf,(char *)inet_ntoa(sockin->sin_addr));
-
- /* Look up the remote host name. */
- if ((hp = gethostbyaddr((char *) &sockin->sin_addr,
- sizeof(sockin->sin_addr),
- AF_INET)) == 0) {
- DEBUG(1,("Gethostbyaddr failed for %s\n",addr_buf));
-#ifdef ALLOW_PURE_ADDRESSES
- takeAddressAsHostname = True;
-#else
- return(False);
-#endif
- }
-
- /* Save the host name. A later gethostbyxxx() call may clobber it. */
- f->name = StrnCpy(name_buf,
- takeAddressAsHostname? f->addr : hp->h_name,
- sizeof(name_buf) - 1);
-
- /*
- * Verify that the host name does not belong to someone else. If host
- * name verification fails, pretend that the host name lookup failed.
- */
- if (!takeAddressAsHostname && !matchname(f->name, sockin->sin_addr))
- {
- DEBUG(0,("Matchname failed\n"));
- return(False);
- }
-
- return(True);
+ BOOL only_ip = True;
+
+ if (!list)
+ return True;
+
+ for (; *list ; list++) {
+ /* factor out the special strings */
+ if (!strcasecmp(*list, "ALL") || !strcasecmp(*list, "FAIL") ||
+ !strcasecmp(*list, "EXCEPT")) {
+ continue;
+ }
+
+ if (!is_ipaddress(*list)) {
+ /*
+ * if we failed, make sure that it was not because the token
+ * was a network/netmask pair. Only network/netmask pairs
+ * have a '/' in them
+ */
+ if ((strchr_m(*list, '/')) == NULL) {
+ only_ip = False;
+ DEBUG(3,("only_ipaddrs_in_list: list has non-ip address (%s)\n", *list));
+ break;
+ }
+ }
+ }
+
+ return only_ip;
}
-/* matchname - determine if host name matches IP address */
-static int matchname(char *remotehost,struct in_addr addr)
+/* return true if access should be allowed to a service for a socket */
+BOOL check_access(int sock, const char **allow_list, const char **deny_list)
{
- struct hostent *hp;
- int i;
-
- if ((hp = Get_Hostbyname(remotehost)) == 0) {
- DEBUG(0,("Get_Hostbyname(%s): lookup failure", remotehost));
- return (Bad);
- }
-
- /*
- * Make sure that gethostbyname() returns the "correct" host name.
- * Unfortunately, gethostbyname("localhost") sometimes yields
- * "localhost.domain". Since the latter host name comes from the
- * local DNS, we just have to trust it (all bets are off if the local
- * DNS is perverted). We always check the address list, though.
- */
-
- if (strcasecmp(remotehost, hp->h_name)
- && strcasecmp(remotehost, "localhost")) {
- DEBUG(0,("host name/name mismatch: %s != %s",
- remotehost, hp->h_name));
- return (Bad);
- }
+ BOOL ret = False;
+ BOOL only_ip = False;
- /* Look up the host address in the address list we just got. */
- for (i = 0; hp->h_addr_list[i]; i++) {
- if (memcmp(hp->h_addr_list[i], (caddr_t) & addr, sizeof(addr)) == 0)
- return (Good);
- }
-
- /*
- * The host name does not map to the original host address. Perhaps
- * someone has compromised a name server. More likely someone botched
- * it, but that could be dangerous, too.
- */
-
- DEBUG(0,("host name/address mismatch: %s != %s",
- inet_ntoa(addr), hp->h_name));
- return (Bad);
-}
-
+ if ((!deny_list || *deny_list==0) && (!allow_list || *allow_list==0))
+ ret = True;
+
+ if (!ret) {
+ /* bypass gethostbyaddr() calls if the lists only contain IP addrs */
+ if (only_ipaddrs_in_list(allow_list) && only_ipaddrs_in_list(deny_list)) {
+ only_ip = True;
+ DEBUG (3, ("check_access: no hostnames in host allow/deny list.\n"));
+ ret = allow_access(deny_list,allow_list, "", get_socket_addr(sock));
+ } else {
+ DEBUG (3, ("check_access: hostnames in host allow/deny list.\n"));
+ ret = allow_access(deny_list,allow_list, get_socket_name(sock,True),
+ get_socket_addr(sock));
+ }
+
+ if (ret) {
+ DEBUG(2,("Allowed connection from %s (%s)\n",
+ only_ip ? "" : get_socket_name(sock,True),
+ get_socket_addr(sock)));
+ } else {
+ DEBUG(0,("Denied connection from %s (%s)\n",
+ only_ip ? "" : get_socket_name(sock,True),
+ get_socket_addr(sock)));
+ }
+ }
+ return(ret);
+}
git.samba.org / samba.git / blobdiff