/* shared.cc: shared data area support. Copyright 1996, 1997, 1998, 1999, 2000 Cygnus Solutions. This file is part of Cygwin. This software is a copyrighted work licensed under the terms of the Cygwin license. Please consult the file "CYGWIN_LICENSE" for details. */ #include "winsup.h" #include #include #include #include #include #include "pinfo.h" #define SHAREDVER (unsigned)(cygwin_version.api_major << 16 | \ cygwin_version.api_minor) shared_info NO_COPY *cygwin_shared = NULL; /* The handle of the shared data area. */ HANDLE cygwin_shared_h = NULL; /* General purpose security attribute objects for global use. */ SECURITY_ATTRIBUTES NO_COPY sec_none; SECURITY_ATTRIBUTES NO_COPY sec_none_nih; SECURITY_ATTRIBUTES NO_COPY sec_all; SECURITY_ATTRIBUTES NO_COPY sec_all_nih; char * __stdcall shared_name (const char *str, int num) { static NO_COPY char buf[MAX_PATH] = {0}; char envbuf[6]; __small_sprintf (buf, "%s.%s.%d", cygwin_version.shared_id, str, num); if (GetEnvironmentVariable("CYGWIN_TESTING", envbuf, 5)) strcat(buf, cygwin_version.dll_build_date); return buf; } /* Open the shared memory map. */ static void __stdcall open_shared_file_map () { cygwin_shared = (shared_info *) open_shared ("shared", cygwin_shared_h, sizeof (*cygwin_shared), (void *)0xa000000); ProtectHandle (cygwin_shared); } void * __stdcall open_shared (const char *name, HANDLE &shared_h, DWORD size, void *addr) { void *shared; if (!shared_h) { char *mapname; if (!name) mapname = NULL; else { mapname = shared_name (name, 0); shared_h = OpenFileMappingA (FILE_MAP_READ | FILE_MAP_WRITE, TRUE, mapname); } if (!shared_h && !(shared_h = CreateFileMappingA ((HANDLE) 0xffffffff, &sec_all, PAGE_READWRITE, 0, size, mapname))) api_fatal ("CreateFileMappingA, %E. Terminating."); } shared = (shared_info *) MapViewOfFileEx (shared_h, FILE_MAP_READ | FILE_MAP_WRITE, 0, 0, 0, addr); if (!shared) { /* Probably win95, so try without specifying the address. */ shared = (shared_info *) MapViewOfFileEx (shared_h, FILE_MAP_READ|FILE_MAP_WRITE, 0,0,0,0); } if (!shared) api_fatal ("MapViewOfFileEx, %E. Terminating."); debug_printf ("name %s, shared %p, h %p", name, shared, shared_h); /* FIXME: I couldn't find anywhere in the documentation a note about whether the memory is initialized to zero. The code assumes it does and since this part seems to be working, we'll leave it as is. */ return shared; } void shared_info::initialize () { /* Ya, Win32 provides a way for a dll to watch when it's first loaded. We may eventually want to use it but for now we have this. */ if (inited) { if (inited != SHAREDVER) api_fatal ("Shared region version mismatch. Version %x != %x.\n" "Are you using multiple versions of cygwin1.dll?\n" "Run 'cygcheck -r -s -v' to find out.", inited, SHAREDVER); return; } /* Initialize the mount table. */ mount.init (); /* Initialize the queue of deleted files. */ delqueue.init (); /* Initialize tty table. */ tty.init (); /* Fetch misc. registry entries. */ reg_key reg (KEY_READ, NULL); /* Note that reserving a huge amount of heap space does not result in swapping since we are not committing it. */ /* FIXME: We should not be restricted to a fixed size heap no matter what the fixed size is. */ heap_chunk_in_mb = reg.get_int ("heap_chunk_in_mb", 128); if (heap_chunk_in_mb < 4) { heap_chunk_in_mb = 4; reg.set_int ("heap_chunk_in_mb", heap_chunk_in_mb); } inited = SHAREDVER; } void __stdcall shared_init () { open_shared_file_map (); cygwin_shared->initialize (); } void __stdcall shared_terminate () { if (cygwin_shared_h) ForceCloseHandle (cygwin_shared_h); } unsigned shared_info::heap_chunk_size () { return heap_chunk_in_mb << 20; } /* For apps that wish to access the shared data. */ shared_info * cygwin_getshared () { return cygwin_shared; } /* * Function to return a common SECURITY_DESCRIPTOR * that * allows all access. */ static NO_COPY SECURITY_DESCRIPTOR *null_sdp = 0; SECURITY_DESCRIPTOR *__stdcall get_null_sd () { static NO_COPY SECURITY_DESCRIPTOR sd; if (null_sdp == 0) { InitializeSecurityDescriptor (&sd, SECURITY_DESCRIPTOR_REVISION); SetSecurityDescriptorDacl (&sd, TRUE, 0, FALSE); null_sdp = &sd; } return null_sdp; } extern PSID get_admin_sid (); extern PSID get_system_sid (); extern PSID get_creator_owner_sid (); PSECURITY_ATTRIBUTES __stdcall sec_user (PVOID sa_buf, PSID sid2, BOOL inherit) { if (! sa_buf) return inherit ? &sec_none_nih : &sec_none; PSECURITY_ATTRIBUTES psa = (PSECURITY_ATTRIBUTES) sa_buf; PSECURITY_DESCRIPTOR psd = (PSECURITY_DESCRIPTOR) ((char *) sa_buf + sizeof (*psa)); PACL acl = (PACL) ((char *) sa_buf + sizeof (*psa) + sizeof (*psd)); char sid_buf[MAX_SID_LEN]; PSID sid = (PSID) sid_buf; if (myself->use_psid) CopySid (MAX_SID_LEN, sid, myself->psid); else if (! lookup_name (getlogin (), myself->logsrv, sid)) return inherit ? &sec_none_nih : &sec_none; size_t acl_len = sizeof (ACL) + 4 * (sizeof (ACCESS_ALLOWED_ACE) - sizeof (DWORD)) + GetLengthSid (sid) + GetLengthSid (get_admin_sid ()) + GetLengthSid (get_system_sid ()) + GetLengthSid (get_creator_owner_sid ()); if (sid2) acl_len += sizeof (ACCESS_ALLOWED_ACE) - sizeof (DWORD) + GetLengthSid (sid2); if (! InitializeAcl (acl, acl_len, ACL_REVISION)) debug_printf("InitializeAcl %E"); if (! AddAccessAllowedAce (acl, ACL_REVISION, SPECIFIC_RIGHTS_ALL | STANDARD_RIGHTS_ALL, sid)) debug_printf("AddAccessAllowedAce(%s) %E", getlogin()); if (! AddAccessAllowedAce (acl, ACL_REVISION, SPECIFIC_RIGHTS_ALL | STANDARD_RIGHTS_ALL, get_admin_sid ())) debug_printf("AddAccessAllowedAce(admin) %E"); if (! AddAccessAllowedAce (acl, ACL_REVISION, SPECIFIC_RIGHTS_ALL | STANDARD_RIGHTS_ALL, get_system_sid ())) debug_printf("AddAccessAllowedAce(system) %E"); if (! AddAccessAllowedAce (acl, ACL_REVISION, SPECIFIC_RIGHTS_ALL | STANDARD_RIGHTS_ALL, get_creator_owner_sid ())) debug_printf("AddAccessAllowedAce(creator_owner) %E"); if (sid2) if (! AddAccessAllowedAce (acl, ACL_REVISION, SPECIFIC_RIGHTS_ALL | STANDARD_RIGHTS_ALL, sid2)) debug_printf("AddAccessAllowedAce(sid2) %E"); if (! InitializeSecurityDescriptor (psd, SECURITY_DESCRIPTOR_REVISION)) debug_printf("InitializeSecurityDescriptor %E"); /* * Setting the owner lets the created security attribute not work * on NT4 SP3 Server. Don't know why, but the function still does * what it should do also if the owner isn't set. */ #if 0 if (! SetSecurityDescriptorOwner (psd, sid, FALSE)) debug_printf("SetSecurityDescriptorOwner %E"); #endif if (! SetSecurityDescriptorDacl (psd, TRUE, acl, FALSE)) debug_printf("SetSecurityDescriptorDacl %E"); psa->nLength = sizeof (SECURITY_ATTRIBUTES); psa->lpSecurityDescriptor = psd; psa->bInheritHandle = inherit; return psa; } SECURITY_ATTRIBUTES *__stdcall sec_user_nih (PVOID sa_buf, PSID sid2) { return sec_user (sa_buf, sid2, FALSE); }