/* * Copyright 1990, 1998 The Open Group Copyright 2002 Sun Microsystems, Inc. All rights reserved. Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation. The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. Except as contained in this notice, the name of a copyright holder shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization from the copyright holder. * * Author: Keith Packard, MIT X Consortium */ /* * Access control for XDMCP - keep a database of allowable display addresses * and (potentially) a list of hosts to send ForwardQuery packets to */ # include "dm.h" # include "dm_error.h" #ifdef XDMCP # include # include # include # include # include # include "dm_socket.h" # include # if defined(IPv6) && defined(AF_INET6) # include # endif #define ALIAS_CHARACTER '%' #define NEGATE_CHARACTER '!' #define CHOOSER_STRING "CHOOSER" #define BROADCAST_STRING "BROADCAST" #define NOBROADCAST_STRING "NOBROADCAST" #define LISTEN_STRING "LISTEN" #define WILDCARD_STRING "*" #define HOST_ALIAS 0 #define HOST_ADDRESS 1 #define HOST_BROADCAST 2 #define HOST_CHOOSER 3 #define HOST_NOBROADCAST 4 #define HOST_ANYADDR 5 typedef struct _hostEntry { struct _hostEntry *next; int type; union _hostOrAlias { char *aliasName; ARRAY8 hostAddress; } entry; int hopCount; } HostEntry; #define DISPLAY_ALIAS 0 #define DISPLAY_PATTERN 1 #define DISPLAY_ADDRESS 2 #define DISPLAY_LISTEN 3 typedef struct _displayEntry { struct _displayEntry *next; int type; int notAllowed; int notBroadcast; int chooser; union _displayType { char *aliasName; char *displayPattern; struct _display { ARRAY8 clientAddress; CARD16 connectionType; } displayAddress; } entry; HostEntry *hosts; } DisplayEntry; static DisplayEntry *database; static ARRAY8 localAddress; ARRAY8Ptr getLocalAddress (void) { static int haveLocalAddress; if (!haveLocalAddress) { #if defined(IPv6) && defined(AF_INET6) struct addrinfo *ai; if (getaddrinfo(localHostname(), NULL, NULL, &ai) != 0) { XdmcpAllocARRAY8 (&localAddress, 4); localAddress.data[0] = 127; localAddress.data[1] = 0; localAddress.data[2] = 0; localAddress.data[3] = 1; } else { if (ai->ai_addr->sa_family == AF_INET) { XdmcpAllocARRAY8 (&localAddress, sizeof(struct in_addr)); memcpy(localAddress.data, &((struct sockaddr_in *)ai->ai_addr)->sin_addr, sizeof(struct in_addr)); } else if (ai->ai_addr->sa_family == AF_INET6) { XdmcpAllocARRAY8 (&localAddress, sizeof(struct in6_addr)); memcpy(localAddress.data, &((struct sockaddr_in6 *)ai->ai_addr)->sin6_addr, sizeof(struct in6_addr)); } freeaddrinfo(ai); } #else struct hostent *hostent; hostent = gethostbyname (localHostname()); if (hostent != NULL) { XdmcpAllocARRAY8 (&localAddress, hostent->h_length); memmove(localAddress.data, hostent->h_addr, hostent->h_length); } else { /* Assume 127.0.0.1 */ XdmcpAllocARRAY8 (&localAddress, 4); localAddress.data[0] = 127; localAddress.data[1] = 0; localAddress.data[2] = 0; localAddress.data[3] = 1; } #endif } return &localAddress; } static void FreeHostEntry (HostEntry *h) { switch (h->type) { case HOST_ALIAS: free (h->entry.aliasName); break; case HOST_ADDRESS: XdmcpDisposeARRAY8 (&h->entry.hostAddress); break; case HOST_CHOOSER: break; } free ((char *) h); } static void FreeDisplayEntry (DisplayEntry *d) { HostEntry *h, *next; switch (d->type) { case DISPLAY_ALIAS: free (d->entry.aliasName); break; case DISPLAY_PATTERN: free (d->entry.displayPattern); break; case DISPLAY_ADDRESS: XdmcpDisposeARRAY8 (&d->entry.displayAddress.clientAddress); break; case DISPLAY_LISTEN: /* do nothing - this case doesn't use the d->entry union */ break; } for (h = d->hosts; h; h = next) { next = h->next; FreeHostEntry (h); } free ((char *) d); } static void FreeAccessDatabase (void) { DisplayEntry *d, *next; for (d = database; d; d = next) { next = d->next; FreeDisplayEntry (d); } database = NULL; } #define WORD_LEN 256 static char wordBuffer[WORD_LEN]; static int nextIsEOF; static char * ReadWord (FILE *file, int EOFatEOL) { int c; char *wordp; int quoted; wordp = wordBuffer; if (nextIsEOF) { nextIsEOF = FALSE; return NULL; } quoted = FALSE; for (;wordp - wordBuffer < sizeof(wordBuffer)-2;) { c = getc (file); switch (c) { case '#': if (quoted) { *wordp++ = c; break; } while ((c = getc (file)) != EOF && c != '\n') ; case '\n': case EOF: if (c == EOF || (EOFatEOL && !quoted)) { ungetc (c, file); if (wordp == wordBuffer) return NULL; *wordp = '\0'; nextIsEOF = TRUE; return wordBuffer; } case ' ': case '\t': if (wordp != wordBuffer) { ungetc (c, file); *wordp = '\0'; return wordBuffer; } break; case '\\': if (!quoted) { quoted = TRUE; continue; } default: if (wordp < &(wordBuffer[WORD_LEN])) *wordp++ = c; break; } quoted = FALSE; } return NULL; } static HostEntry * ReadHostEntry (FILE *file) { char *hostOrAlias; HostEntry *h; tryagain: hostOrAlias = ReadWord (file, TRUE); if (!hostOrAlias) return NULL; h = (HostEntry *) malloc (sizeof (DisplayEntry)); h->hopCount = 1; if (*hostOrAlias == ALIAS_CHARACTER) { h->type = HOST_ALIAS; h->entry.aliasName = malloc (strlen (hostOrAlias) + 1); if (!h->entry.aliasName) { free ((char *) h); return NULL; } strcpy (h->entry.aliasName, hostOrAlias); } else if (!strcmp (hostOrAlias, CHOOSER_STRING)) { h->type = HOST_CHOOSER; } else if (!strcmp (hostOrAlias, BROADCAST_STRING)) { h->type = HOST_BROADCAST; } else if (!strcmp (hostOrAlias, NOBROADCAST_STRING)) { h->type = HOST_NOBROADCAST; } else if (!strcmp (hostOrAlias, WILDCARD_STRING)) { h->type = HOST_ANYADDR; h->entry.hostAddress.length = 0; } else { void *addr=NULL; size_t addr_length=0; #if defined(IPv6) && defined(AF_INET6) struct addrinfo *ai = NULL; #else struct hostent *hostent = gethostbyname (hostOrAlias); #endif char *hops = strrchr(hostOrAlias, '/'); if (hops) { *(hops++) = '\0'; h->hopCount = strtol(hops, NULL, 10); if (h->hopCount < 1) h->hopCount = 1; } #if defined(IPv6) && defined(AF_INET6) if (getaddrinfo(hostOrAlias, NULL, NULL, &ai) == 0) { if (ai->ai_addr->sa_family == AF_INET) { addr = &((struct sockaddr_in *)ai->ai_addr)->sin_addr; addr_length = sizeof(struct in_addr); } else if (ai->ai_addr->sa_family == AF_INET6) { addr = &((struct sockaddr_in6 *)ai->ai_addr)->sin6_addr; addr_length = sizeof(struct in6_addr); } } #else if (hostent) { addr = hostent->h_addr; addr_length = hostent->h_length; } #endif h->type = HOST_ADDRESS; if (!addr) { Debug ("No such host %s\n", hostOrAlias); LogError ("Access file \"%s\", host \"%s\" not found\n", accessFile, hostOrAlias); free ((char *) h); #if defined(IPv6) && defined(AF_INET6) if (ai) freeaddrinfo(ai); #endif goto tryagain; } if (!XdmcpAllocARRAY8 (&h->entry.hostAddress, addr_length)) { LogOutOfMem ("ReadHostEntry\n"); free ((char *) h); #if defined(IPv6) && defined(AF_INET6) if (ai) freeaddrinfo(ai); #endif return NULL; } memmove( h->entry.hostAddress.data, addr, addr_length); #if defined(IPv6) && defined(AF_INET6) if (ai) freeaddrinfo(ai); #endif } return h; } static int HasGlobCharacters (char *s) { for (;;) switch (*s++) { case '?': case '*': return 1; case '\0': return 0; } } static DisplayEntry * ReadDisplayEntry (FILE *file) { char *displayOrAlias; DisplayEntry *d; struct _display *display; HostEntry *h, **prev; displayOrAlias = ReadWord (file, FALSE); if (!displayOrAlias) return NULL; d = (DisplayEntry *) malloc (sizeof (DisplayEntry)); d->notAllowed = 0; d->notBroadcast = 0; d->chooser = 0; if (*displayOrAlias == ALIAS_CHARACTER) { d->type = DISPLAY_ALIAS; d->entry.aliasName = malloc (strlen (displayOrAlias) + 1); if (!d->entry.aliasName) { free ((char *) d); return NULL; } strcpy (d->entry.aliasName, displayOrAlias); } else if (!strcmp(displayOrAlias, LISTEN_STRING)) { d->type = DISPLAY_LISTEN; } else { if (*displayOrAlias == NEGATE_CHARACTER) { d->notAllowed = 1; ++displayOrAlias; } if (HasGlobCharacters (displayOrAlias)) { d->type = DISPLAY_PATTERN; d->entry.displayPattern = malloc (strlen (displayOrAlias) + 1); if (!d->entry.displayPattern) { free ((char *) d); return NULL; } strcpy (d->entry.displayPattern, displayOrAlias); } else { void *addr = NULL; size_t addr_length = 0; int addrtype = 0; #if defined(IPv6) && defined(AF_INET6) struct addrinfo *ai = NULL; if (getaddrinfo(displayOrAlias, NULL, NULL, &ai) == 0) { addrtype = ai->ai_addr->sa_family; if (addrtype == AF_INET) { addr = &((struct sockaddr_in *)ai->ai_addr)->sin_addr; addr_length = sizeof(struct in_addr); } else if (addrtype == AF_INET6) { addr = &((struct sockaddr_in6 *)ai->ai_addr)->sin6_addr; addr_length = sizeof(struct in6_addr); } } #else struct hostent *hostent; if ((hostent = gethostbyname (displayOrAlias)) != NULL) { Debug("ReadDisplayEntry: %s\n", displayOrAlias); addr = hostent->h_addr; addrtype = hostent->h_addrtype; addr_length = hostent->h_length; } #endif if (addr == NULL) { LogError ("Access file %s, display %s unknown\n", accessFile, displayOrAlias); free ((char *) d); #if defined(IPv6) && defined(AF_INET6) if (ai) freeaddrinfo(ai); #endif return NULL; } d->type = DISPLAY_ADDRESS; display = &d->entry.displayAddress; if (!XdmcpAllocARRAY8 (&display->clientAddress, addr_length)) { free ((char *) d); #if defined(IPv6) && defined(AF_INET6) if (ai) freeaddrinfo(ai); #endif return NULL; } memmove( display->clientAddress.data, addr, addr_length); #if defined(IPv6) && defined(AF_INET6) if (ai) freeaddrinfo(ai); #endif switch (addrtype) { #ifdef AF_UNIX case AF_UNIX: display->connectionType = FamilyLocal; break; #endif #ifdef AF_INET case AF_INET: display->connectionType = FamilyInternet; break; #endif #if defined(IPv6) && defined(AF_INET6) case AF_INET6: display->connectionType = FamilyInternet6; break; #endif #ifdef AF_DECnet case AF_DECnet: display->connectionType = FamilyDECnet; break; #endif default: display->connectionType = FamilyLocal; break; } } } prev = &d->hosts; while ((h = ReadHostEntry (file))) { if (h->type == HOST_CHOOSER) { FreeHostEntry (h); d->chooser = 1; } else if (h->type == HOST_NOBROADCAST) { FreeHostEntry (h); d->notBroadcast = 1; } else if (h->type == HOST_ANYADDR) { if (d->type == DISPLAY_LISTEN) { *prev = h; prev = &h->next; } else { Debug("Wildcard host specified in Xaccess for type other than LISTEN -- ignoring\n"); FreeHostEntry (h); } } else { *prev = h; prev = &h->next; } } *prev = NULL; return d; } static void ReadAccessDatabase (FILE *file) { DisplayEntry *d, **prev; prev = &database; while ((d = ReadDisplayEntry (file))) { *prev = d; prev = &d->next; } *prev = NULL; } int ScanAccessDatabase (void) { FILE *datafile; FreeAccessDatabase (); if (*accessFile) { datafile = fopen (accessFile, "r"); if (!datafile) { LogError ("Cannot open access control file %s, no XDMCP reqeusts will be granted\n", accessFile); return 0; } ReadAccessDatabase (datafile); fclose (datafile); } return 1; } /* * calls the given function for each valid indirect entry. Returns TRUE if * the local host exists on any of the lists, else FALSE */ #define MAX_DEPTH 32 static int indirectAlias ( char *alias, ARRAY8Ptr clientAddress, CARD16 connectionType, ChooserFunc function, char *closure, int depth, int broadcast); static int scanHostlist ( HostEntry *h, ARRAY8Ptr clientAddress, CARD16 connectionType, ChooserFunc function, char *closure, int depth, int broadcast) { int haveLocalhost = 0; for (; h; h = h->next) { switch (h->type) { case HOST_ALIAS: if (indirectAlias (h->entry.aliasName, clientAddress, connectionType, function, closure, depth, broadcast)) haveLocalhost = 1; break; case HOST_ADDRESS: if (XdmcpARRAY8Equal (getLocalAddress(), &h->entry.hostAddress)) haveLocalhost = 1; else if (function) (*function) (connectionType, &h->entry.hostAddress, closure); break; case HOST_BROADCAST: if (broadcast) { ARRAY8 temp; if (function) { temp.data = (BYTE *) BROADCAST_STRING; temp.length = strlen ((char *)temp.data); (*function) (connectionType, &temp, closure); } } break; } } return haveLocalhost; } /* Returns non-0 iff string is matched by pattern. Does case folding. */ static int patternMatch (char *string, char *pattern) { int p, s; if (!string) string = ""; for (;;) { s = *string++; switch (p = *pattern++) { case '*': if (!*pattern) return 1; for (string--; *string; string++) if (patternMatch (string, pattern)) return 1; return 0; case '?': if (s == '\0') return 0; break; case '\0': return s == '\0'; case '\\': p = *pattern++; /* fall through */ default: if (isupper(p)) p = tolower(p); if (isupper(s)) s = tolower(s); if (p != s) return 0; } } } static int indirectAlias ( char *alias, ARRAY8Ptr clientAddress, CARD16 connectionType, ChooserFunc function, char *closure, int depth, int broadcast) { DisplayEntry *d; int haveLocalhost = 0; if (depth == MAX_DEPTH) return 0; for (d = database; d; d = d->next) { if (d->type != DISPLAY_ALIAS || !patternMatch (alias, d->entry.aliasName)) continue; if (scanHostlist (d->hosts, clientAddress, connectionType, function, closure, depth + 1, broadcast)) { haveLocalhost = 1; } } return haveLocalhost; } int ForEachMatchingIndirectHost ( ARRAY8Ptr clientAddress, CARD16 connectionType, ChooserFunc function, char *closure) { int haveLocalhost = 0; DisplayEntry *d; char *clientName = NULL; for (d = database; d; d = d->next) { switch (d->type) { case DISPLAY_ALIAS: case DISPLAY_LISTEN: continue; case DISPLAY_PATTERN: if (!clientName) clientName = NetworkAddressToHostname (connectionType, clientAddress); if (!patternMatch (clientName, d->entry.displayPattern)) continue; break; case DISPLAY_ADDRESS: if (d->entry.displayAddress.connectionType != connectionType || !XdmcpARRAY8Equal (&d->entry.displayAddress.clientAddress, clientAddress)) { continue; } break; } if (!d->hosts) continue; if (d->notAllowed) break; if (d->chooser) { ARRAY8Ptr choice; choice = IndirectChoice (clientAddress, connectionType); if (!choice || XdmcpARRAY8Equal (getLocalAddress(), choice)) haveLocalhost = 1; else (*function) (connectionType, choice, closure); } else if (scanHostlist (d->hosts, clientAddress, connectionType, function, closure, 0, FALSE)) { haveLocalhost = 1; } break; } if (clientName) free (clientName); return haveLocalhost; } int UseChooser ( ARRAY8Ptr clientAddress, CARD16 connectionType) { DisplayEntry *d; char *clientName = NULL; for (d = database; d; d = d->next) { switch (d->type) { case DISPLAY_ALIAS: case DISPLAY_LISTEN: continue; case DISPLAY_PATTERN: if (!clientName) clientName = NetworkAddressToHostname (connectionType, clientAddress); if (!patternMatch (clientName, d->entry.displayPattern)) continue; break; case DISPLAY_ADDRESS: if (d->entry.displayAddress.connectionType != connectionType || !XdmcpARRAY8Equal (&d->entry.displayAddress.clientAddress, clientAddress)) { continue; } break; } if (!d->hosts) continue; if (d->notAllowed) break; if (d->chooser && !IndirectChoice (clientAddress, connectionType)) { if (clientName) free (clientName); return 1; } break; } if (clientName) free (clientName); return 0; } void ForEachChooserHost ( ARRAY8Ptr clientAddress, CARD16 connectionType, ChooserFunc function, char *closure) { int haveLocalhost = 0; DisplayEntry *d; char *clientName = NULL; for (d = database; d; d = d->next) { switch (d->type) { case DISPLAY_ALIAS: case DISPLAY_LISTEN: continue; case DISPLAY_PATTERN: if (!clientName) clientName = NetworkAddressToHostname (connectionType, clientAddress); if (!patternMatch (clientName, d->entry.displayPattern)) continue; break; case DISPLAY_ADDRESS: if (d->entry.displayAddress.connectionType != connectionType || !XdmcpARRAY8Equal (&d->entry.displayAddress.clientAddress, clientAddress)) { continue; } break; } if (!d->hosts) continue; if (d->notAllowed) break; if (!d->chooser) break; if (scanHostlist (d->hosts, clientAddress, connectionType, function, closure, 0, TRUE)) { haveLocalhost = 1; } break; } if (clientName) free (clientName); if (haveLocalhost) (*function) (connectionType, getLocalAddress(), closure); } /* * returns TRUE if the given client is acceptable to the local host. The * given display client is acceptable if it occurs without a host list. */ int AcceptableDisplayAddress ( ARRAY8Ptr clientAddress, CARD16 connectionType, xdmOpCode type) { DisplayEntry *d; char *clientName = NULL; if (!*accessFile) return 1; if (type == INDIRECT_QUERY) return 1; for (d = database; d; d = d->next) { if (d->hosts) continue; switch (d->type) { case DISPLAY_ALIAS: case DISPLAY_LISTEN: continue; case DISPLAY_PATTERN: if (!clientName) clientName = NetworkAddressToHostname (connectionType, clientAddress); if (!patternMatch (clientName, d->entry.displayPattern)) continue; break; case DISPLAY_ADDRESS: if (d->entry.displayAddress.connectionType != connectionType || !XdmcpARRAY8Equal (&d->entry.displayAddress.clientAddress, clientAddress)) { continue; } break; } break; } if (clientName) free (clientName); return (d != 0) && (d->notAllowed == 0) && (type == BROADCAST_QUERY ? d->notBroadcast == 0 : 1); } void ForEachListenAddr ( ListenFunc listenfunction, ListenFunc mcastfunction, void **closure) { DisplayEntry *d; HostEntry *h; int listenFound = 0; for (d = database; d != NULL ; d = d->next) { if (d->type == DISPLAY_LISTEN) { listenFound = 1; h = d->hosts; if (h != NULL) { (*listenfunction) (&h->entry.hostAddress, closure); for (h = h->next; h != NULL; h = h->next) { (*mcastfunction) (&h->entry.hostAddress, closure); } } } } if (!listenFound) { (*listenfunction) (NULL, closure); #if defined(IPv6) && defined(AF_INET6) && defined(XDM_DEFAULT_MCAST_ADDR6) { /* Join default IPv6 Multicast Group */ static ARRAY8 defaultMcastAddress; if (defaultMcastAddress.length == 0) { struct in6_addr addr6; if (inet_pton(AF_INET6,XDM_DEFAULT_MCAST_ADDR6,&addr6) == 1) { if (!XdmcpAllocARRAY8 (&defaultMcastAddress, sizeof(struct in6_addr))) { LogOutOfMem ("ReadHostEntry\n"); defaultMcastAddress.length = -1; } else { memcpy(defaultMcastAddress.data, &addr6, sizeof(struct in6_addr)); } } else { defaultMcastAddress.length = -1; } } if ( defaultMcastAddress.length == sizeof(struct in6_addr) ) { (*mcastfunction) (&defaultMcastAddress, closure); } } #endif } } #endif /* XDMCP */