vendor/krb5/1.15.1

1 files changed, 525 insertions, 0 deletions

diff --git a/src/ccapi/server/ccs_lock_state.c b/src/ccapi/server/ccs_lock_state.c
new file mode 100644
index 000000000000..681661ea6b37
--- /dev/null
+++ b/src/ccapi/server/ccs_lock_state.c
@@ -0,0 +1,525 @@
+/* ccapi/server/ccs_lock_state.c */
+/*
+ * Copyright 2006, 2007 Massachusetts Institute of Technology.
+ * All Rights Reserved.
+ *
+ * Export of this software from the United States of America may
+ * require a specific license from the United States Government.
+ * It is the responsibility of any person or organization contemplating
+ * export to obtain such a license before exporting.
+ *
+ * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
+ * distribute this software and its documentation for any purpose and
+ * without fee is hereby granted, provided that the above copyright
+ * notice appear in all copies and that both that copyright notice and
+ * this permission notice appear in supporting documentation, and that
+ * the name of M.I.T. not be used in advertising or publicity pertaining
+ * to distribution of the software without specific, written prior
+ * permission.  Furthermore if you modify this software you must label
+ * your software as modified software and not distribute it in such a
+ * fashion that it might be confused with the original M.I.T. software.
+ * M.I.T. makes no representations about the suitability of
+ * this software for any purpose.  It is provided "as is" without express
+ * or implied warranty.
+ */
+
+#include "ccs_common.h"
+
+struct ccs_lock_state_d {
+    cc_int32 invalid_object_err;
+    cc_int32 pending_lock_err;
+    cc_int32 no_lock_err;
+    ccs_lock_array_t locks;
+    cc_uint64 first_pending_lock_index;
+};
+
+struct ccs_lock_state_d ccs_lock_state_initializer = { 1, 1, 1, NULL, 0 };
+
+/* ------------------------------------------------------------------------ */
+
+cc_int32 ccs_lock_state_new (ccs_lock_state_t *out_lock_state,
+                             cc_int32          in_invalid_object_err,
+                             cc_int32          in_pending_lock_err,
+                             cc_int32          in_no_lock_err)
+{
+    cc_int32 err = ccNoError;
+    ccs_lock_state_t lock_state = NULL;
+
+    if (!out_lock_state) { err = cci_check_error (ccErrBadParam); }
+
+    if (!err) {
+        lock_state = malloc (sizeof (*lock_state));
+        if (lock_state) {
+            *lock_state = ccs_lock_state_initializer;
+        } else {
+            err = cci_check_error (ccErrNoMem);
+        }
+    }
+
+    if (!err) {
+        err = ccs_lock_array_new (&lock_state->locks);
+    }
+
+    if (!err) {
+        lock_state->invalid_object_err = in_invalid_object_err;
+        lock_state->pending_lock_err = in_pending_lock_err;
+        lock_state->no_lock_err = in_no_lock_err;
+
+        *out_lock_state = lock_state;
+        lock_state = NULL;
+    }
+
+    ccs_lock_state_release (lock_state);
+
+    return cci_check_error (err);
+}
+
+/* ------------------------------------------------------------------------ */
+
+cc_int32 ccs_lock_state_release (ccs_lock_state_t io_lock_state)
+{
+    cc_int32 err = ccNoError;
+
+    if (!err && io_lock_state) {
+        ccs_lock_array_release (io_lock_state->locks);
+        free (io_lock_state);
+    }
+
+    return cci_check_error (err);
+}
+
+#ifdef TARGET_OS_MAC
+#pragma mark -
+#endif
+
+/* ------------------------------------------------------------------------ */
+
+static cc_int32 ccs_lock_status_add_pending_lock (ccs_lock_state_t  io_lock_state,
+                                                  ccs_pipe_t        in_client_pipe,
+                                                  ccs_pipe_t        in_reply_pipe,
+                                                  cc_uint32         in_lock_type,
+                                                  cc_uint64        *out_lock_index)
+{
+    cc_int32 err = ccNoError;
+    ccs_lock_t lock = NULL;
+
+    if (!io_lock_state                  ) { err = cci_check_error (ccErrBadParam); }
+    if (!ccs_pipe_valid (in_client_pipe)) { err = cci_check_error (ccErrBadParam); }
+    if (!ccs_pipe_valid (in_reply_pipe) ) { err = cci_check_error (ccErrBadParam); }
+
+    if (!err) {
+        err = ccs_lock_new (&lock, in_lock_type,
+                            io_lock_state->invalid_object_err,
+                            in_client_pipe, in_reply_pipe,
+                            io_lock_state);
+    }
+
+    if (!err) {
+        err = ccs_lock_array_insert (io_lock_state->locks, lock,
+                                     ccs_lock_array_count (io_lock_state->locks));
+        if (!err) { lock = NULL; /* take ownership */ }
+    }
+
+    if (!err) {
+        *out_lock_index = ccs_lock_array_count (io_lock_state->locks) - 1;
+    }
+
+    ccs_lock_release (lock);
+
+    return cci_check_error (err);
+}
+
+/* ------------------------------------------------------------------------ */
+
+static cc_int32 ccs_lock_status_remove_lock (ccs_lock_state_t io_lock_state,
+                                             cc_uint64        in_lock_index)
+{
+    cc_int32 err = ccNoError;
+
+    if (!io_lock_state) { err = cci_check_error (ccErrBadParam); }
+
+    if (!err) {
+        err = ccs_lock_array_remove (io_lock_state->locks, in_lock_index);
+
+        if (!err && in_lock_index < io_lock_state->first_pending_lock_index) {
+            io_lock_state->first_pending_lock_index--;
+        }
+    }
+
+    return cci_check_error (err);
+}
+
+/* ------------------------------------------------------------------------ */
+
+static cc_int32 ccs_lock_status_grant_lock (ccs_lock_state_t io_lock_state,
+                                            cc_uint64        in_pending_lock_index)
+{
+    cc_int32 err = ccNoError;
+    ccs_lock_t pending_lock = NULL;
+    cc_uint32 type = 0;
+
+    if (!io_lock_state) { err = cci_check_error (ccErrBadParam); }
+
+    if (!err) {
+        pending_lock = ccs_lock_array_object_at_index (io_lock_state->locks,
+                                                       in_pending_lock_index);
+        if (!pending_lock || in_pending_lock_index < io_lock_state->first_pending_lock_index) {
+            err = cci_check_error (ccErrBadParam);
+        }
+    }
+
+    if (!err) {
+        err = ccs_lock_type (pending_lock, &type);
+    }
+
+    if (!err && (type == cc_lock_upgrade || type == cc_lock_downgrade)) {
+        /* lock upgrades or downgrades.  Find the old lock and remove it. */
+        ccs_pipe_t pending_client_pipe = CCS_PIPE_NULL;
+
+        err = ccs_lock_client_pipe (pending_lock, &pending_client_pipe);
+
+        if (!err) {
+            cc_uint64 i;
+
+            for (i = 0; !err && i < io_lock_state->first_pending_lock_index; i++) {
+                ccs_lock_t lock = ccs_lock_array_object_at_index (io_lock_state->locks, i);
+                cc_uint32 is_lock_for_client = 0;
+
+                err = ccs_lock_is_for_client_pipe (lock, pending_client_pipe, &is_lock_for_client);
+
+                if (!err && is_lock_for_client) {
+                    cci_debug_printf ("%s: Removing old lock %p at index %d to replace with pending lock %p.",
+                                      __FUNCTION__, lock, (int) i, pending_lock);
+                    err = ccs_lock_status_remove_lock (io_lock_state, i);
+                    if (!err) { i--; in_pending_lock_index--; /* We removed one so back up an index */ }
+                    break;
+                }
+            }
+        }
+    }
+
+    if (!err) {
+        cc_uint64 new_lock_index = 0;
+
+        err = ccs_lock_array_move (io_lock_state->locks,
+                                   in_pending_lock_index,
+                                   io_lock_state->first_pending_lock_index,
+                                   &new_lock_index);
+        if (!err) { io_lock_state->first_pending_lock_index++; }
+    }
+
+    if (!err) {
+        err = ccs_lock_grant_lock (pending_lock);
+    }
+
+    return cci_check_error (err);
+}
+
+#ifdef TARGET_OS_MAC
+#pragma mark -
+#endif
+
+/* ------------------------------------------------------------------------ */
+
+static cc_int32 ccs_lock_state_check_pending_lock (ccs_lock_state_t  io_lock_state,
+                                                   ccs_pipe_t        in_pending_lock_client_pipe,
+                                                   cc_uint32         in_pending_lock_type,
+                                                   cc_uint32        *out_grant_lock)
+{
+    cc_int32 err = ccNoError;
+    cc_uint32 is_write_locked = 0;
+    cc_uint32 client_has_lock = 0;
+    cc_uint32 other_clients_have_locks = 0;
+    cc_uint32 client_lock_type = 0;
+    cc_uint64 client_lock_index = 0;
+    cc_uint32 grant_lock = 0;
+
+    if (!io_lock_state                               ) { err = cci_check_error (ccErrBadParam); }
+    if (!ccs_pipe_valid (in_pending_lock_client_pipe)) { err = cci_check_error (ccErrBadParam); }
+    if (!out_grant_lock                              ) { err = cci_check_error (ccErrBadParam); }
+
+    if (!err) {
+        cc_uint64 i;
+        cc_uint64 lock_count = io_lock_state->first_pending_lock_index;
+
+        for (i = 0; !err && i < lock_count; i++) {
+            ccs_lock_t lock = ccs_lock_array_object_at_index (io_lock_state->locks, i);
+            cc_uint32 lock_type = 0;
+            cc_uint32 lock_is_for_client = 0;
+
+            err = ccs_lock_type (lock, &lock_type);
+
+            if (!err) {
+                err = ccs_lock_is_for_client_pipe (lock, in_pending_lock_client_pipe,
+                                                   &lock_is_for_client);
+            }
+
+            if (!err) {
+                if (lock_type == cc_lock_write || lock_type == cc_lock_upgrade) {
+                    is_write_locked = 1;
+                }
+
+                if (!lock_is_for_client) {
+                    other_clients_have_locks = 1;
+
+                } else if (!client_has_lock) { /* only record type of 1st lock */
+                    client_has_lock = 1;
+                    client_lock_type = lock_type;
+                    client_lock_index = i;
+                }
+            }
+        }
+    }
+
+    if (!err) {
+        cc_uint64 lock_count = io_lock_state->first_pending_lock_index;
+
+        if (in_pending_lock_type == cc_lock_write) {
+            if (client_has_lock) {
+                err = cci_check_error (ccErrBadLockType);
+            } else {
+                grant_lock = (lock_count == 0);
+            }
+
+        } else if (in_pending_lock_type == cc_lock_read) {
+            if (client_has_lock) {
+                err = cci_check_error (ccErrBadLockType);
+            } else {
+                grant_lock = !is_write_locked;
+            }
+
+        } else if (in_pending_lock_type == cc_lock_upgrade) {
+            if (!client_has_lock || (client_lock_type != cc_lock_read &&
+                                     client_lock_type != cc_lock_downgrade)) {
+                err = cci_check_error (ccErrBadLockType);
+            } else {
+                /* don't grant if other clients have read locks */
+                grant_lock = !other_clients_have_locks;
+            }
+
+        } else if (in_pending_lock_type == cc_lock_downgrade) {
+            if (!client_has_lock || (client_lock_type != cc_lock_write &&
+                                     client_lock_type != cc_lock_upgrade)) {
+                err = cci_check_error (ccErrBadLockType);
+            } else {
+                /* downgrades can never block */
+                grant_lock = 1;
+            }
+        } else {
+            err = cci_check_error (ccErrBadLockType);
+        }
+    }
+
+    if (!err) {
+        *out_grant_lock = grant_lock;
+    }
+
+    return cci_check_error (err);
+}
+
+/* ------------------------------------------------------------------------ */
+
+static cc_int32 ccs_lock_status_try_to_grant_pending_locks (ccs_lock_state_t io_lock_state)
+{
+    cc_int32 err = ccNoError;
+    cc_uint32 done = 0;
+
+    if (!io_lock_state) { err = cci_check_error (ccErrBadParam); }
+
+    /* Look at the pending locks and see if we can grant them.
+     * Note that downgrade locks mean we must check all pending locks each pass
+     * since a downgrade lock might be last in the list. */
+
+    while (!err && !done) {
+        cc_uint64 i;
+        cc_uint64 count = ccs_lock_array_count (io_lock_state->locks);
+        cc_uint32 granted_lock = 0;
+
+        for (i = io_lock_state->first_pending_lock_index; !err && i < count; i++) {
+            ccs_lock_t lock = ccs_lock_array_object_at_index (io_lock_state->locks, i);
+            cc_uint32 lock_type = 0;
+            ccs_pipe_t client_pipe = CCS_PIPE_NULL;
+            cc_uint32 can_grant_lock_now = 0;
+
+            err = ccs_lock_client_pipe (lock, &client_pipe);
+
+            if (!err) {
+                err = ccs_lock_type (lock, &lock_type);
+            }
+
+            if (!err) {
+                err = ccs_lock_state_check_pending_lock (io_lock_state, client_pipe,
+                                                         lock_type, &can_grant_lock_now);
+            }
+
+            if (!err && can_grant_lock_now) {
+                err = ccs_lock_status_grant_lock (io_lock_state, i);
+                if (!err) { granted_lock = 1; }
+            }
+        }
+
+        if (!err && !granted_lock) {
+            /* we walked over all the locks and couldn't grant any of them */
+            done = 1;
+        }
+    }
+
+    return cci_check_error (err);
+}
+
+#ifdef TARGET_OS_MAC
+#pragma mark -
+#endif
+
+/* ------------------------------------------------------------------------ */
+
+cc_int32 ccs_lock_state_add (ccs_lock_state_t  io_lock_state,
+                             ccs_pipe_t        in_client_pipe,
+                             ccs_pipe_t        in_reply_pipe,
+                             cc_uint32         in_lock_type,
+                             cc_uint32         in_block,
+                             cc_uint32        *out_will_send_reply)
+{
+    cc_int32 err = ccNoError;
+    cc_uint32 can_grant_lock_now = 0;
+
+    if (!io_lock_state                  ) { err = cci_check_error (ccErrBadParam); }
+    if (!ccs_pipe_valid (in_client_pipe)) { err = cci_check_error (ccErrBadParam); }
+    if (!ccs_pipe_valid (in_reply_pipe) ) { err = cci_check_error (ccErrBadParam); }
+    if (!out_will_send_reply            ) { err = cci_check_error (ccErrBadParam); }
+
+    if (!err) {
+        /* Sanity check: if there are any pending locks for this client
+         * the client must have timed out waiting for our reply.  Remove any
+         * existing pending locks for the client. */
+        cc_uint64 i;
+
+        for (i = io_lock_state->first_pending_lock_index; !err && i < ccs_lock_array_count (io_lock_state->locks); i++) {
+            ccs_lock_t lock = ccs_lock_array_object_at_index (io_lock_state->locks, i);
+            cc_uint32 has_pending_lock_for_client = 0;
+
+            err = ccs_lock_is_for_client_pipe (lock, in_client_pipe, &has_pending_lock_for_client);
+
+            if (!err && has_pending_lock_for_client) {
+                cci_debug_printf ("WARNING %s: Removing unexpected pending lock %p at index %d.",
+                                  __FUNCTION__, lock, (int) i);
+                err = ccs_lock_status_remove_lock (io_lock_state, i);
+                if (!err) { i--;  /* We removed one so back up an index */ }
+            }
+        }
+    }
+
+    if (!err) {
+        err = ccs_lock_state_check_pending_lock (io_lock_state, in_client_pipe,
+                                                 in_lock_type, &can_grant_lock_now);
+    }
+
+    if (!err) {
+        if (!can_grant_lock_now && (in_block == cc_lock_noblock)) {
+            err = cci_check_error (io_lock_state->pending_lock_err);
+
+        } else {
+            cc_uint64 new_lock_index = 0;
+
+            err = ccs_lock_status_add_pending_lock (io_lock_state,
+                                                    in_client_pipe,
+                                                    in_reply_pipe,
+                                                    in_lock_type,
+                                                    &new_lock_index);
+
+            if (!err && can_grant_lock_now) {
+                err = ccs_lock_status_grant_lock (io_lock_state, new_lock_index);
+
+                if (!err && (in_lock_type == cc_lock_downgrade)) {
+                    /* downgrades can allow us to grant other locks */
+                    err = ccs_lock_status_try_to_grant_pending_locks (io_lock_state);
+                }
+            }
+        }
+    }
+
+    if (!err) {
+        /* ccs_lock_state_add sends its replies via callback so caller shouldn't */
+        *out_will_send_reply = 1;
+    }
+
+    return cci_check_error (err);
+}
+
+/* ------------------------------------------------------------------------ */
+
+cc_int32 ccs_lock_state_remove (ccs_lock_state_t io_lock_state,
+                                ccs_pipe_t       in_client_pipe)
+{
+    cc_int32 err = ccNoError;
+    cc_uint32 found_lock = 0;
+
+    if (!io_lock_state                  ) { err = cci_check_error (ccErrBadParam); }
+    if (!ccs_pipe_valid (in_client_pipe)) { err = cci_check_error (ccErrBadParam); }
+
+    if (!err) {
+        cc_uint64 i;
+
+        /* Remove all locks for this client.
+         * There should only be one so warn if there are multiple */
+        for (i = 0; !err && i < io_lock_state->first_pending_lock_index; i++) {
+            ccs_lock_t lock = ccs_lock_array_object_at_index (io_lock_state->locks, i);
+            cc_uint32 is_for_client = 0;
+
+            err = ccs_lock_is_for_client_pipe (lock, in_client_pipe, &is_for_client);
+
+            if (!err && is_for_client) {
+                if (found_lock) {
+                    cci_debug_printf ("WARNING %s: Found multiple locks for client.",
+                                      __FUNCTION__);
+                }
+
+                found_lock = 1;
+
+                cci_debug_printf ("%s: Removing lock %p at index %d.", __FUNCTION__, lock, (int) i);
+                err = ccs_lock_status_remove_lock (io_lock_state, i);
+                if (!err) { i--;  /* We removed one so back up an index */ }
+            }
+        }
+    }
+
+    if (!err && !found_lock) {
+        err = cci_check_error (io_lock_state->no_lock_err);
+    }
+
+    if (!err) {
+        err = ccs_lock_status_try_to_grant_pending_locks (io_lock_state);
+    }
+
+    return cci_check_error (err);
+}
+
+/* ------------------------------------------------------------------------ */
+
+cc_int32 ccs_lock_state_invalidate_lock (ccs_lock_state_t io_lock_state,
+                                         ccs_lock_t       in_lock)
+{
+    cc_int32 err = ccNoError;
+
+    if (!io_lock_state) { err = ccErrBadParam; }
+
+    if (!err) {
+        cc_uint64 i;
+        cc_uint64 count = ccs_lock_array_count (io_lock_state->locks);
+
+        for (i = 0; !err && i < count; i++) {
+            ccs_lock_t lock = ccs_lock_array_object_at_index (io_lock_state->locks, i);
+
+            if (lock == in_lock) {
+                err = ccs_lock_status_remove_lock (io_lock_state, i);
+
+                if (!err) {
+                    err = ccs_lock_status_try_to_grant_pending_locks (io_lock_state);
+                    break;
+                }
+            }
+        }
+    }
+
+    return cci_check_error (err);
+}