1 files changed, 308 insertions, 0 deletions
diff --git a/source3/lib/sharesec.c b/source3/lib/sharesec.c
new file mode 100644
index 0000000000..b98e304582
--- /dev/null
+++ b/source3/lib/sharesec.c
@@ -0,0 +1,308 @@
+/* 
+ *  Unix SMB/Netbios implementation.
+ *  SEC_DESC handling functions
+ *  Copyright (C) Jeremy R. Allison            1995-2003.
+ *  
+ *  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.
+ */
+
+#include "includes.h"
+
+/*******************************************************************
+ Create the share security tdb.
+ ********************************************************************/
+
+static TDB_CONTEXT *share_tdb; /* used for share security descriptors */
+#define SHARE_DATABASE_VERSION_V1 1
+#define SHARE_DATABASE_VERSION_V2 2 /* version id in little endian. */
+
+/* Map generic permissions to file object specific permissions */
+
+static struct generic_mapping file_generic_mapping = {
+        FILE_GENERIC_READ,
+        FILE_GENERIC_WRITE,
+        FILE_GENERIC_EXECUTE,
+        FILE_GENERIC_ALL
+};
+
+
+BOOL share_info_db_init(void)
+{
+	const char *vstring = "INFO/version";
+	int32 vers_id;
+ 
+	if (share_tdb) {
+		return True;
+	}
+
+	share_tdb = tdb_open_log(lock_path("share_info.tdb"), 0, TDB_DEFAULT, O_RDWR|O_CREAT, 0600);
+	if (!share_tdb) {
+		DEBUG(0,("Failed to open share info database %s (%s)\n",
+			lock_path("share_info.tdb"), strerror(errno) ));
+		return False;
+	}
+ 
+	/* handle a Samba upgrade */
+	tdb_lock_bystring(share_tdb, vstring, 0);
+
+	/* Cope with byte-reversed older versions of the db. */
+	vers_id = tdb_fetch_int32(share_tdb, vstring);
+	if ((vers_id == SHARE_DATABASE_VERSION_V1) || (IREV(vers_id) == SHARE_DATABASE_VERSION_V1)) {
+		/* Written on a bigendian machine with old fetch_int code. Save as le. */
+		tdb_store_int32(share_tdb, vstring, SHARE_DATABASE_VERSION_V2);
+		vers_id = SHARE_DATABASE_VERSION_V2;
+	}
+
+	if (vers_id != SHARE_DATABASE_VERSION_V2) {
+		tdb_traverse(share_tdb, tdb_traverse_delete_fn, NULL);
+		tdb_store_int32(share_tdb, vstring, SHARE_DATABASE_VERSION_V2);
+	}
+	tdb_unlock_bystring(share_tdb, vstring);
+
+	return True;
+}
+
+/*******************************************************************
+ Fake up a Everyone, default access as a default.
+ def_access is a GENERIC_XXX access mode.
+ ********************************************************************/
+
+SEC_DESC *get_share_security_default( TALLOC_CTX *ctx, size_t *psize, uint32 def_access)
+{
+	SEC_ACCESS sa;
+	SEC_ACE ace;
+	SEC_ACL *psa = NULL;
+	SEC_DESC *psd = NULL;
+	uint32 spec_access = def_access;
+
+	se_map_generic(&spec_access, &file_generic_mapping);
+
+	init_sec_access(&sa, def_access | spec_access );
+	init_sec_ace(&ace, &global_sid_World, SEC_ACE_TYPE_ACCESS_ALLOWED, sa, 0);
+
+	if ((psa = make_sec_acl(ctx, NT4_ACL_REVISION, 1, &ace)) != NULL) {
+		psd = make_sec_desc(ctx, SEC_DESC_REVISION, SEC_DESC_SELF_RELATIVE, NULL, NULL, NULL, psa, psize);
+	}
+
+	if (!psd) {
+		DEBUG(0,("get_share_security: Failed to make SEC_DESC.\n"));
+		return NULL;
+	}
+
+	return psd;
+}
+
+/*******************************************************************
+ Pull a security descriptor from the share tdb.
+ ********************************************************************/
+
+SEC_DESC *get_share_security( TALLOC_CTX *ctx, int snum, size_t *psize)
+{
+	prs_struct ps;
+	fstring key;
+	SEC_DESC *psd = NULL;
+
+	if (!share_info_db_init()) {
+		return NULL;
+	}
+
+	*psize = 0;
+
+	/* Fetch security descriptor from tdb */
+ 
+	slprintf(key, sizeof(key)-1, "SECDESC/%s", lp_servicename(snum));
+ 
+	if (tdb_prs_fetch(share_tdb, key, &ps, ctx)!=0 ||
+		!sec_io_desc("get_share_security", &psd, &ps, 1)) {
+ 
+		DEBUG(4,("get_share_security: using default secdesc for %s\n", lp_servicename(snum) ));
+ 
+		return get_share_security_default(ctx, psize, GENERIC_ALL_ACCESS);
+	}
+
+	if (psd)
+		*psize = sec_desc_size(psd);
+
+	prs_mem_free(&ps);
+	return psd;
+}
+
+/*******************************************************************
+ Store a security descriptor in the share db.
+ ********************************************************************/
+
+BOOL set_share_security(TALLOC_CTX *ctx, const char *share_name, SEC_DESC *psd)
+{
+	prs_struct ps;
+	TALLOC_CTX *mem_ctx = NULL;
+	fstring key;
+	BOOL ret = False;
+
+	if (!share_info_db_init()) {
+		return False;
+	}
+
+	mem_ctx = talloc_init("set_share_security");
+	if (mem_ctx == NULL)
+		return False;
+
+	prs_init(&ps, (uint32)sec_desc_size(psd), mem_ctx, MARSHALL);
+ 
+	if (!sec_io_desc("share_security", &psd, &ps, 1))
+		goto out;
+ 
+	slprintf(key, sizeof(key)-1, "SECDESC/%s", share_name);
+ 
+	if (tdb_prs_store(share_tdb, key, &ps)==0) {
+		ret = True;
+		DEBUG(5,("set_share_security: stored secdesc for %s\n", share_name ));
+	} else {
+		DEBUG(1,("set_share_security: Failed to store secdesc for %s\n", share_name ));
+	} 
+
+	/* Free malloc'ed memory */
+ 
+out:
+ 
+	prs_mem_free(&ps);
+	if (mem_ctx)
+		talloc_destroy(mem_ctx);
+	return ret;
+}
+
+/*******************************************************************
+ Delete a security descriptor.
+********************************************************************/
+
+BOOL delete_share_security(int snum)
+{
+	TDB_DATA kbuf;
+	fstring key;
+
+	slprintf(key, sizeof(key)-1, "SECDESC/%s", lp_servicename(snum));
+	kbuf.dptr = key;
+	kbuf.dsize = strlen(key)+1;
+
+	if (tdb_delete(share_tdb, kbuf) != 0) {
+		DEBUG(0,("delete_share_security: Failed to delete entry for share %s\n",
+				lp_servicename(snum) ));
+		return False;
+	}
+
+	return True;
+}
+
+/***************************************************************************
+ Parse the contents of an acl string from a usershare file.
+***************************************************************************/
+
+BOOL parse_usershare_acl(TALLOC_CTX *ctx, const char *acl_str, SEC_DESC **ppsd)
+{
+	size_t s_size = 0;
+	const char *pacl = acl_str;
+	int num_aces = 0;
+	SEC_ACE *ace_list = NULL;
+	SEC_ACL *psa = NULL;
+	SEC_DESC *psd = NULL;
+	size_t sd_size = 0;
+	int i;
+
+	*ppsd = NULL;
+
+	/* If the acl string is blank return "Everyone:R" */
+	if (!*acl_str) {
+		SEC_DESC *default_psd = get_share_security_default(ctx, &s_size, GENERIC_READ_ACCESS);
+		if (!default_psd) {
+			return False;
+		}
+		*ppsd = default_psd;
+		return True;
+	}
+
+	num_aces = 1;
+
+	/* Add the number of ',' characters to get the number of aces. */
+	num_aces += count_chars(pacl,',');
+
+	ace_list = TALLOC_ARRAY(ctx, SEC_ACE, num_aces);
+	if (!ace_list) {
+		return False;
+	}
+
+	for (i = 0; i < num_aces; i++) {
+		SEC_ACCESS sa;
+		uint32 g_access;
+		uint32 s_access;
+		DOM_SID sid;
+		fstring sidstr;
+		uint8 type = SEC_ACE_TYPE_ACCESS_ALLOWED;
+
+		if (!next_token(&pacl, sidstr, ":", sizeof(sidstr))) {
+			DEBUG(0,("parse_usershare_acl: malformed usershare acl looking "
+				"for ':' in string '%s'\n", pacl));
+			return False;
+		}
+
+		if (!string_to_sid(&sid, sidstr)) {
+			DEBUG(0,("parse_usershare_acl: failed to convert %s to sid.\n",
+				sidstr ));
+			return False;
+		}
+
+		switch (*pacl) {
+			case 'F': /* Full Control, ie. R+W */
+			case 'f': /* Full Control, ie. R+W */
+				s_access = g_access = GENERIC_ALL_ACCESS;
+				break;
+			case 'R': /* Read only. */
+			case 'r': /* Read only. */
+				s_access = g_access = GENERIC_READ_ACCESS;
+				break;
+			case 'D': /* Deny all to this SID. */
+			case 'd': /* Deny all to this SID. */
+				type = SEC_ACE_TYPE_ACCESS_DENIED;
+				s_access = g_access = GENERIC_ALL_ACCESS;
+				break;
+			default:
+				DEBUG(0,("parse_usershare_acl: unknown acl type at %s.\n",
+					pacl ));
+				return False;
+		}
+
+		pacl++;
+		if (*pacl && *pacl != ',') {
+			DEBUG(0,("parse_usershare_acl: bad acl string at %s.\n",
+				pacl ));
+			return False;
+		}
+		pacl++; /* Go past any ',' */
+
+		se_map_generic(&s_access, &file_generic_mapping);
+		init_sec_access(&sa, g_access | s_access );
+		init_sec_ace(&ace_list[i], &sid, type, sa, 0);
+	}
+
+	if ((psa = make_sec_acl(ctx, NT4_ACL_REVISION, num_aces, ace_list)) != NULL) {
+		psd = make_sec_desc(ctx, SEC_DESC_REVISION, SEC_DESC_SELF_RELATIVE, NULL, NULL, NULL, psa, &sd_size);
+	}
+
+	if (!psd) {
+		DEBUG(0,("parse_usershare_acl: Failed to make SEC_DESC.\n"));
+		return False;
+	}
+
+	*ppsd = psd;
+	return True;
+}