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-rw-r--r--source3/lib/sharesec.c588
1 files changed, 588 insertions, 0 deletions
diff --git a/source3/lib/sharesec.c b/source3/lib/sharesec.c
new file mode 100644
index 0000000..fbb2d47
--- /dev/null
+++ b/source3/lib/sharesec.c
@@ -0,0 +1,588 @@
+/*
+ * 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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "includes.h"
+#include "system/filesys.h"
+#include "../libcli/security/security.h"
+#include "../librpc/gen_ndr/ndr_security.h"
+#include "dbwrap/dbwrap.h"
+#include "dbwrap/dbwrap_open.h"
+#include "util_tdb.h"
+#include "libcli/util/ntstatus.h"
+
+/*******************************************************************
+ Create the share security tdb.
+ ********************************************************************/
+
+static struct db_context *share_db; /* used for share security descriptors */
+#define SHARE_DATABASE_VERSION_V1 1
+#define SHARE_DATABASE_VERSION_V2 2 /* version id in little endian. */
+#define SHARE_DATABASE_VERSION_V3 3 /* canonicalized sharenames as lower case */
+
+#define SHARE_SECURITY_DB_KEY_PREFIX_STR "SECDESC/"
+/* Map generic permissions to file object specific permissions */
+
+extern const struct generic_mapping file_generic_mapping;
+
+static int delete_fn(struct db_record *rec, void *priv)
+{
+ dbwrap_record_delete(rec);
+ return 0;
+}
+
+/*****************************************************
+ Looking for keys of the form: SHARE_SECURITY_DB_KEY_PREFIX_STR + "non lower case str".
+ If we find one re-write it into a canonical case form.
+*****************************************************/
+
+static int upgrade_v2_to_v3(struct db_record *rec, void *priv)
+{
+ size_t prefix_len = strlen(SHARE_SECURITY_DB_KEY_PREFIX_STR);
+ const char *servicename = NULL;
+ char *c_servicename = NULL;
+ char *newkey = NULL;
+ bool *p_upgrade_ok = (bool *)priv;
+ NTSTATUS status;
+ TDB_DATA key;
+ TDB_DATA value;
+
+ key = dbwrap_record_get_key(rec);
+
+ /* Is there space for a one character sharename ? */
+ if (key.dsize <= prefix_len+2) {
+ return 0;
+ }
+
+ /* Does it start with the share key prefix ? */
+ if (memcmp(key.dptr, SHARE_SECURITY_DB_KEY_PREFIX_STR,
+ prefix_len) != 0) {
+ return 0;
+ }
+
+ /* Is it a null terminated string as a key ? */
+ if (key.dptr[key.dsize-1] != '\0') {
+ return 0;
+ }
+
+ /* Bytes after the prefix are the sharename string. */
+ servicename = (char *)&key.dptr[prefix_len];
+ c_servicename = canonicalize_servicename(talloc_tos(), servicename);
+ if (!c_servicename) {
+ smb_panic("out of memory upgrading share security db from v2 -> v3");
+ }
+
+ if (strcmp(servicename, c_servicename) == 0) {
+ /* Old and new names match. No canonicalization needed. */
+ TALLOC_FREE(c_servicename);
+ return 0;
+ }
+
+ /* Oops. Need to canonicalize name, delete old then store new. */
+ status = dbwrap_record_delete(rec);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("upgrade_v2_to_v3: Failed to delete secdesc for "
+ "%s: %s\n", (const char *)key.dptr,
+ nt_errstr(status)));
+ TALLOC_FREE(c_servicename);
+ *p_upgrade_ok = false;
+ return -1;
+ } else {
+ DEBUG(10, ("upgrade_v2_to_v3: deleted secdesc for "
+ "%s\n", (const char *)key.dptr));
+ }
+
+ if (!(newkey = talloc_asprintf(talloc_tos(),
+ SHARE_SECURITY_DB_KEY_PREFIX_STR "%s",
+ c_servicename))) {
+ smb_panic("out of memory upgrading share security db from v2 -> v3");
+ }
+
+ value = dbwrap_record_get_value(rec);
+ status = dbwrap_store(share_db,
+ string_term_tdb_data(newkey),
+ value,
+ TDB_REPLACE);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("upgrade_v2_to_v3: Failed to store secdesc for "
+ "%s: %s\n", c_servicename, nt_errstr(status)));
+ TALLOC_FREE(c_servicename);
+ TALLOC_FREE(newkey);
+ *p_upgrade_ok = false;
+ return -1;
+ } else {
+ DEBUG(10, ("upgrade_v2_to_v3: stored secdesc for "
+ "%s\n", newkey ));
+ }
+
+ TALLOC_FREE(newkey);
+ TALLOC_FREE(c_servicename);
+
+ return 0;
+}
+
+NTSTATUS share_info_db_init(void)
+{
+ const char *vstring = "INFO/version";
+ int32_t vers_id = 0;
+ bool upgrade_ok = true;
+ NTSTATUS status;
+ char *db_path;
+
+ if (share_db != NULL) {
+ return NT_STATUS_OK;
+ }
+
+ db_path = state_path(talloc_tos(), "share_info.tdb");
+ if (db_path == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ share_db = db_open(NULL, db_path, 0,
+ TDB_DEFAULT, O_RDWR|O_CREAT, 0600,
+ DBWRAP_LOCK_ORDER_1, DBWRAP_FLAG_NONE);
+ if (share_db == NULL) {
+ DEBUG(0,("Failed to open share info database %s (%s)\n",
+ db_path, strerror(errno)));
+ TALLOC_FREE(db_path);
+ return map_nt_error_from_unix_common(errno);
+ }
+ TALLOC_FREE(db_path);
+
+ status = dbwrap_fetch_int32_bystring(share_db, vstring, &vers_id);
+ if (!NT_STATUS_IS_OK(status)) {
+ vers_id = 0;
+ }
+
+ if (vers_id == SHARE_DATABASE_VERSION_V3) {
+ return NT_STATUS_OK;
+ }
+
+ if (dbwrap_transaction_start(share_db) != 0) {
+ DEBUG(0, ("transaction_start failed\n"));
+ TALLOC_FREE(share_db);
+ return NT_STATUS_INTERNAL_DB_ERROR;
+ }
+
+ status = dbwrap_fetch_int32_bystring(share_db, vstring, &vers_id);
+ if (!NT_STATUS_IS_OK(status)) {
+ vers_id = 0;
+ }
+
+ if (vers_id == SHARE_DATABASE_VERSION_V3) {
+ /*
+ * Race condition
+ */
+ if (dbwrap_transaction_cancel(share_db)) {
+ smb_panic("transaction_cancel failed");
+ }
+ return NT_STATUS_OK;
+ }
+
+ /* Move to at least V2. */
+
+ /* Cope with byte-reversed older versions of the db. */
+ 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. */
+
+ status = dbwrap_store_int32_bystring(
+ share_db, vstring, SHARE_DATABASE_VERSION_V2);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("dbwrap_store_int32 failed: %s\n",
+ nt_errstr(status)));
+ goto cancel;
+ }
+ vers_id = SHARE_DATABASE_VERSION_V2;
+ }
+
+ if (vers_id != SHARE_DATABASE_VERSION_V2) {
+ status = dbwrap_traverse(share_db, delete_fn, NULL, NULL);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("traverse failed\n"));
+ goto cancel;
+ }
+ status = dbwrap_store_int32_bystring(
+ share_db, vstring, SHARE_DATABASE_VERSION_V2);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("dbwrap_store_int32 failed: %s\n",
+ nt_errstr(status)));
+ goto cancel;
+ }
+ }
+
+ /* Finally upgrade to version 3, with canonicalized sharenames. */
+
+ status = dbwrap_traverse(share_db, upgrade_v2_to_v3, &upgrade_ok, NULL);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("traverse failed\n"));
+ goto cancel;
+ }
+ if (!upgrade_ok) {
+ DBG_ERR("upgrade failed.\n");
+ status = NT_STATUS_INTERNAL_ERROR;
+ goto cancel;
+ }
+
+ status = dbwrap_store_int32_bystring(
+ share_db, vstring, SHARE_DATABASE_VERSION_V3);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("dbwrap_store_int32 failed: %s\n",
+ nt_errstr(status)));
+ goto cancel;
+ }
+
+ if (dbwrap_transaction_commit(share_db) != 0) {
+ DEBUG(0, ("transaction_commit failed\n"));
+ return NT_STATUS_INTERNAL_ERROR;
+ }
+
+ return NT_STATUS_OK;
+
+ cancel:
+ if (dbwrap_transaction_cancel(share_db)) {
+ smb_panic("transaction_cancel failed");
+ }
+
+ return status;
+}
+
+/*******************************************************************
+ Fake up a Everyone, default access as a default.
+ def_access is a GENERIC_XXX access mode.
+ ********************************************************************/
+
+static struct security_descriptor *get_share_security_default(TALLOC_CTX *ctx,
+ size_t *psize,
+ uint32_t def_access)
+{
+ uint32_t sa;
+ struct security_ace ace;
+ struct security_acl *psa = NULL;
+ struct security_descriptor *psd = NULL;
+ uint32_t spec_access = def_access;
+
+ se_map_generic(&spec_access, &file_generic_mapping);
+
+ 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, SECURITY_DESCRIPTOR_REVISION_1,
+ 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.
+ ********************************************************************/
+
+struct security_descriptor *get_share_security( TALLOC_CTX *ctx, const char *servicename,
+ size_t *psize)
+{
+ char *key;
+ struct security_descriptor *psd = NULL;
+ TDB_DATA data;
+ char *c_servicename = canonicalize_servicename(talloc_tos(), servicename);
+ NTSTATUS status;
+
+ if (!c_servicename) {
+ return NULL;
+ }
+
+ status = share_info_db_init();
+ if (!NT_STATUS_IS_OK(status)) {
+ TALLOC_FREE(c_servicename);
+ return NULL;
+ }
+
+ if (!(key = talloc_asprintf(ctx, SHARE_SECURITY_DB_KEY_PREFIX_STR "%s", c_servicename))) {
+ TALLOC_FREE(c_servicename);
+ DEBUG(0, ("talloc_asprintf failed\n"));
+ return NULL;
+ }
+
+ TALLOC_FREE(c_servicename);
+
+ status = dbwrap_fetch_bystring(share_db, talloc_tos(), key, &data);
+
+ TALLOC_FREE(key);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ return get_share_security_default(ctx, psize,
+ SEC_RIGHTS_DIR_ALL);
+ }
+
+ status = unmarshall_sec_desc(ctx, data.dptr, data.dsize, &psd);
+
+ TALLOC_FREE(data.dptr);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ return get_share_security_default(ctx, psize,
+ SEC_RIGHTS_DIR_ALL);
+ }
+
+ if (psd) {
+ *psize = ndr_size_security_descriptor(psd, 0);
+ } else {
+ return get_share_security_default(ctx, psize,
+ SEC_RIGHTS_DIR_ALL);
+ }
+
+ return psd;
+}
+
+/*******************************************************************
+ Store a security descriptor in the share db.
+ ********************************************************************/
+
+NTSTATUS set_share_security(const char *share_name,
+ struct security_descriptor *psd)
+{
+ TALLOC_CTX *frame = talloc_stackframe();
+ char *key;
+ TDB_DATA blob;
+ NTSTATUS status;
+ char *c_share_name = canonicalize_servicename(frame, share_name);
+
+ if (c_share_name == NULL) {
+ status = NT_STATUS_INVALID_PARAMETER;
+ goto out;
+ }
+
+ status = share_info_db_init();
+ if (!NT_STATUS_IS_OK(status)) {
+ goto out;
+ }
+
+ status = marshall_sec_desc(frame, psd, &blob.dptr, &blob.dsize);
+
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("marshall_sec_desc failed: %s\n",
+ nt_errstr(status)));
+ goto out;
+ }
+
+ if (!(key = talloc_asprintf(frame, SHARE_SECURITY_DB_KEY_PREFIX_STR "%s", c_share_name))) {
+ DEBUG(0, ("talloc_asprintf failed\n"));
+ status = NT_STATUS_NO_MEMORY;
+ goto out;
+ }
+
+ status = dbwrap_trans_store(share_db, string_term_tdb_data(key), blob,
+ TDB_REPLACE);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(1, ("set_share_security: Failed to store secdesc for "
+ "%s: %s\n", share_name, nt_errstr(status)));
+ goto out;
+ }
+
+ DEBUG(5,("set_share_security: stored secdesc for %s\n", share_name ));
+ status = NT_STATUS_OK;
+
+ out:
+ TALLOC_FREE(frame);
+ return status;
+}
+
+/*******************************************************************
+ Delete a security descriptor.
+********************************************************************/
+
+NTSTATUS delete_share_security(const char *servicename)
+{
+ TDB_DATA kbuf;
+ char *key;
+ NTSTATUS status;
+ char *c_servicename = canonicalize_servicename(talloc_tos(), servicename);
+
+ if (c_servicename == NULL) {
+ return NT_STATUS_INVALID_PARAMETER;
+ }
+
+ status = share_info_db_init();
+ if (!NT_STATUS_IS_OK(status)) {
+ TALLOC_FREE(c_servicename);
+ return status;
+ }
+
+ if (!(key = talloc_asprintf(talloc_tos(), SHARE_SECURITY_DB_KEY_PREFIX_STR "%s",
+ c_servicename))) {
+ TALLOC_FREE(c_servicename);
+ return NT_STATUS_NO_MEMORY;
+ }
+ kbuf = string_term_tdb_data(key);
+
+ status = dbwrap_trans_delete(share_db, kbuf);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0, ("delete_share_security: Failed to delete entry for "
+ "share %s: %s\n", c_servicename, nt_errstr(status)));
+ TALLOC_FREE(c_servicename);
+ return status;
+ }
+
+ TALLOC_FREE(c_servicename);
+ return NT_STATUS_OK;
+}
+
+/*******************************************************************
+ Can this user access with share with the required permissions ?
+********************************************************************/
+
+bool share_access_check(const struct security_token *token,
+ const char *sharename,
+ uint32_t desired_access,
+ uint32_t *pgranted)
+{
+ uint32_t granted;
+ NTSTATUS status;
+ struct security_descriptor *psd = NULL;
+ size_t sd_size;
+
+ psd = get_share_security(talloc_tos(), sharename, &sd_size);
+
+ if (!psd) {
+ if (pgranted != NULL) {
+ *pgranted = desired_access;
+ }
+ return false;
+ }
+
+ status = se_file_access_check(psd, token, true, desired_access, &granted);
+
+ TALLOC_FREE(psd);
+
+ if (pgranted != NULL) {
+ *pgranted = granted;
+ }
+
+ return NT_STATUS_IS_OK(status);
+}
+
+/***************************************************************************
+ Parse the contents of an acl string from a usershare file.
+***************************************************************************/
+
+bool parse_usershare_acl(TALLOC_CTX *ctx, const char *acl_str, struct security_descriptor **ppsd)
+{
+ size_t s_size = 0;
+ const char *pacl = acl_str;
+ int num_aces = 0;
+ struct security_ace *ace_list = NULL;
+ struct security_acl *psa = NULL;
+ struct security_descriptor *psd = NULL;
+ size_t sd_size = 0;
+ int i;
+
+ *ppsd = NULL;
+
+ /* If the acl string is blank return "Everyone:R" */
+ if (!*acl_str) {
+ struct security_descriptor *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, struct security_ace, num_aces);
+ if (!ace_list) {
+ return False;
+ }
+
+ for (i = 0; i < num_aces; i++) {
+ uint32_t sa;
+ uint32_t g_access;
+ uint32_t s_access;
+ struct dom_sid sid;
+ char *sidstr;
+ enum security_ace_type type = SEC_ACE_TYPE_ACCESS_ALLOWED;
+
+ if (!next_token_talloc(ctx, &pacl, &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);
+ 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, SECURITY_DESCRIPTOR_REVISION_1,
+ 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;
+}