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-rw-r--r--libportseal/Makefile12
-rw-r--r--libportseal/jhash.h256
-rw-r--r--libportseal/portseal.c271
-rw-r--r--libportseal/portseal.h73
4 files changed, 612 insertions, 0 deletions
diff --git a/libportseal/Makefile b/libportseal/Makefile
new file mode 100644
index 0000000..2e2cc5e
--- /dev/null
+++ b/libportseal/Makefile
@@ -0,0 +1,12 @@
+USE_PKG = liburcu liburcu-cds liburcu-mb
+
+CFLAGS = -std=gnu99 -Wall -ggdb \
+ $(foreach lib,$(USE_PKG),$(shell pkg-config --cflags $(lib)))
+LDFLAGS = -rdynamic -ldl \
+ -L. -lportseal \
+ $(foreach lib,$(USE_PKG),$(shell pkg-config --libs $(lib)))
+
+all: libportseal.so
+
+libportseal.so: portseal.o
+ gcc -shared -o "$@" "$<"
diff --git a/libportseal/jhash.h b/libportseal/jhash.h
new file mode 100644
index 0000000..673989d
--- /dev/null
+++ b/libportseal/jhash.h
@@ -0,0 +1,256 @@
+#ifndef _JHASH_H
+#define _JHASH_H
+
+/*
+ * jhash.h
+ *
+ * Example hash function.
+ *
+ * Copyright 2009-2012 - Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ *
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program for any
+ * purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is
+ * granted, provided the above notices are retained, and a notice that
+ * the code was modified is included with the above copyright notice.
+ */
+
+/*
+ * Hash function
+ * Source: http://burtleburtle.net/bob/c/lookup3.c
+ * Originally Public Domain
+ */
+
+#define rot(x, k) (((x) << (k)) | ((x) >> (32 - (k))))
+
+#define mix(a, b, c) \
+do { \
+ a -= c; a ^= rot(c, 4); c += b; \
+ b -= a; b ^= rot(a, 6); a += c; \
+ c -= b; c ^= rot(b, 8); b += a; \
+ a -= c; a ^= rot(c, 16); c += b; \
+ b -= a; b ^= rot(a, 19); a += c; \
+ c -= b; c ^= rot(b, 4); b += a; \
+} while (0)
+
+#define final(a, b, c) \
+{ \
+ c ^= b; c -= rot(b, 14); \
+ a ^= c; a -= rot(c, 11); \
+ b ^= a; b -= rot(a, 25); \
+ c ^= b; c -= rot(b, 16); \
+ a ^= c; a -= rot(c, 4); \
+ b ^= a; b -= rot(a, 14); \
+ c ^= b; c -= rot(b, 24); \
+}
+
+#if (BYTE_ORDER == LITTLE_ENDIAN)
+#define HASH_LITTLE_ENDIAN 1
+#else
+#define HASH_LITTLE_ENDIAN 0
+#endif
+
+/*
+ *
+ * hashlittle() -- hash a variable-length key into a 32-bit value
+ * k : the key (the unaligned variable-length array of bytes)
+ * length : the length of the key, counting by bytes
+ * initval : can be any 4-byte value
+ * Returns a 32-bit value. Every bit of the key affects every bit of
+ * the return value. Two keys differing by one or two bits will have
+ * totally different hash values.
+ *
+ * The best hash table sizes are powers of 2. There is no need to do
+ * mod a prime (mod is sooo slow!). If you need less than 32 bits,
+ * use a bitmask. For example, if you need only 10 bits, do
+ * h = (h & hashmask(10));
+ * In which case, the hash table should have hashsize(10) elements.
+ *
+ * If you are hashing n strings (uint8_t **)k, do it like this:
+ * for (i = 0, h = 0; i < n; ++i) h = hashlittle(k[i], len[i], h);
+ *
+ * By Bob Jenkins, 2006. bob_jenkins@burtleburtle.net. You may use this
+ * code any way you wish, private, educational, or commercial. It's free.
+ *
+ * Use for hash table lookup, or anything where one collision in 2^^32 is
+ * acceptable. Do NOT use for cryptographic purposes.
+ */
+static
+uint32_t hashlittle(const void *key, size_t length, uint32_t initval)
+{
+ uint32_t a, b, c; /* internal state */
+ union {
+ const void *ptr;
+ size_t i;
+ } u;
+
+ /* Set up the internal state */
+ a = b = c = 0xdeadbeef + ((uint32_t)length) + initval;
+
+ u.ptr = key;
+ if (HASH_LITTLE_ENDIAN && ((u.i & 0x3) == 0)) {
+ const uint32_t *k = (const uint32_t *) key; /* read 32-bit chunks */
+
+ /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */
+ while (length > 12) {
+ a += k[0];
+ b += k[1];
+ c += k[2];
+ mix(a, b, c);
+ length -= 12;
+ k += 3;
+ }
+
+ /*----------------------------- handle the last (probably partial) block */
+ /*
+ * "k[2]&0xffffff" actually reads beyond the end of the string, but
+ * then masks off the part it's not allowed to read. Because the
+ * string is aligned, the masked-off tail is in the same word as the
+ * rest of the string. Every machine with memory protection I've seen
+ * does it on word boundaries, so is OK with this. But VALGRIND will
+ * still catch it and complain. The masking trick does make the hash
+ * noticably faster for short strings (like English words).
+ */
+#ifndef VALGRIND
+
+ switch (length) {
+ case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
+ case 11: c+=k[2]&0xffffff; b+=k[1]; a+=k[0]; break;
+ case 10: c+=k[2]&0xffff; b+=k[1]; a+=k[0]; break;
+ case 9 : c+=k[2]&0xff; b+=k[1]; a+=k[0]; break;
+ case 8 : b+=k[1]; a+=k[0]; break;
+ case 7 : b+=k[1]&0xffffff; a+=k[0]; break;
+ case 6 : b+=k[1]&0xffff; a+=k[0]; break;
+ case 5 : b+=k[1]&0xff; a+=k[0]; break;
+ case 4 : a+=k[0]; break;
+ case 3 : a+=k[0]&0xffffff; break;
+ case 2 : a+=k[0]&0xffff; break;
+ case 1 : a+=k[0]&0xff; break;
+ case 0 : return c; /* zero length strings require no mixing */
+ }
+
+#else /* make valgrind happy */
+ {
+ const uint8_t *k8;
+
+ k8 = (const uint8_t *) k;
+ switch (length) {
+ case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
+ case 11: c+=((uint32_t) k8[10])<<16; /* fall through */
+ case 10: c+=((uint32_t) k8[9])<<8; /* fall through */
+ case 9 : c+=k8[8]; /* fall through */
+ case 8 : b+=k[1]; a+=k[0]; break;
+ case 7 : b+=((uint32_t) k8[6])<<16; /* fall through */
+ case 6 : b+=((uint32_t) k8[5])<<8; /* fall through */
+ case 5 : b+=k8[4]; /* fall through */
+ case 4 : a+=k[0]; break;
+ case 3 : a+=((uint32_t) k8[2])<<16; /* fall through */
+ case 2 : a+=((uint32_t) k8[1])<<8; /* fall through */
+ case 1 : a+=k8[0]; break;
+ case 0 : return c;
+ }
+ }
+#endif /* !valgrind */
+
+ } else if (HASH_LITTLE_ENDIAN && ((u.i & 0x1) == 0)) {
+ const uint16_t *k = (const uint16_t *) key; /* read 16-bit chunks */
+ const uint8_t *k8;
+
+ /*--------------- all but last block: aligned reads and different mixing */
+ while (length > 12)
+ {
+ a += k[0] + (((uint32_t) k[1])<<16);
+ b += k[2] + (((uint32_t) k[3])<<16);
+ c += k[4] + (((uint32_t) k[5])<<16);
+ mix(a, b, c);
+ length -= 12;
+ k += 6;
+ }
+
+ /*----------------------------- handle the last (probably partial) block */
+ k8 = (const uint8_t *) k;
+ switch(length)
+ {
+ case 12: c+=k[4]+(((uint32_t) k[5])<<16);
+ b+=k[2]+(((uint32_t) k[3])<<16);
+ a+=k[0]+(((uint32_t) k[1])<<16);
+ break;
+ case 11: c+=((uint32_t) k8[10])<<16; /* fall through */
+ case 10: c+=k[4];
+ b+=k[2]+(((uint32_t) k[3])<<16);
+ a+=k[0]+(((uint32_t) k[1])<<16);
+ break;
+ case 9 : c+=k8[8]; /* fall through */
+ case 8 : b+=k[2]+(((uint32_t) k[3])<<16);
+ a+=k[0]+(((uint32_t) k[1])<<16);
+ break;
+ case 7 : b+=((uint32_t) k8[6])<<16; /* fall through */
+ case 6 : b+=k[2];
+ a+=k[0]+(((uint32_t) k[1])<<16);
+ break;
+ case 5 : b+=k8[4]; /* fall through */
+ case 4 : a+=k[0]+(((uint32_t) k[1])<<16);
+ break;
+ case 3 : a+=((uint32_t) k8[2])<<16; /* fall through */
+ case 2 : a+=k[0];
+ break;
+ case 1 : a+=k8[0];
+ break;
+ case 0 : return c; /* zero length requires no mixing */
+ }
+
+ } else { /* need to read the key one byte at a time */
+ const uint8_t *k = (const uint8_t *)key;
+
+ /*--------------- all but the last block: affect some 32 bits of (a, b, c) */
+ while (length > 12) {
+ a += k[0];
+ a += ((uint32_t) k[1])<<8;
+ a += ((uint32_t) k[2])<<16;
+ a += ((uint32_t) k[3])<<24;
+ b += k[4];
+ b += ((uint32_t) k[5])<<8;
+ b += ((uint32_t) k[6])<<16;
+ b += ((uint32_t) k[7])<<24;
+ c += k[8];
+ c += ((uint32_t) k[9])<<8;
+ c += ((uint32_t) k[10])<<16;
+ c += ((uint32_t) k[11])<<24;
+ mix(a,b,c);
+ length -= 12;
+ k += 12;
+ }
+
+ /*-------------------------------- last block: affect all 32 bits of (c) */
+ switch (length) { /* all the case statements fall through */
+ case 12: c+=((uint32_t) k[11])<<24;
+ case 11: c+=((uint32_t) k[10])<<16;
+ case 10: c+=((uint32_t) k[9])<<8;
+ case 9 : c+=k[8];
+ case 8 : b+=((uint32_t) k[7])<<24;
+ case 7 : b+=((uint32_t) k[6])<<16;
+ case 6 : b+=((uint32_t) k[5])<<8;
+ case 5 : b+=k[4];
+ case 4 : a+=((uint32_t) k[3])<<24;
+ case 3 : a+=((uint32_t) k[2])<<16;
+ case 2 : a+=((uint32_t) k[1])<<8;
+ case 1 : a+=k[0];
+ break;
+ case 0 : return c;
+ }
+ }
+
+ final(a, b, c);
+ return c;
+}
+
+static inline
+uint32_t jhash(const void *key, size_t length, uint32_t seed)
+{
+ return hashlittle(key, length, seed);
+}
+
+#endif /* _JHASH_H */
diff --git a/libportseal/portseal.c b/libportseal/portseal.c
new file mode 100644
index 0000000..f9523c6
--- /dev/null
+++ b/libportseal/portseal.c
@@ -0,0 +1,271 @@
+#define _GNU_SOURCE
+#include <dlfcn.h>
+#include <errno.h>
+#include <error.h>
+#include <execinfo.h>
+#include <fcntl.h>
+#include <hurd.h>
+#include <mach.h>
+#include <malloc.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <time.h>
+
+#include <urcu.h> /* RCU flavor */
+#include <urcu/rcuhlist.h> /* RCU hlist */
+#include <urcu/rculfhash.h> /* RCU Lock-free hash table */
+#include <urcu/compiler.h> /* For CAA_ARRAY_SIZE */
+#include "jhash.h" /* Example hash function */
+
+#include "portseal.h"
+
+#if 0
+# define TRACE(X...) error(0, 0, X)
+#else
+# define TRACE(X...)
+#endif
+
+#define PORTSEAL_PORTS_SIZE 1000
+int ports[PORTSEAL_PORTS_SIZE];
+
+struct object {
+ struct cds_lfht_node node; /* Chaining in hash table */
+ struct rcu_head rcu_head; /* For call_rcu() */
+ struct cds_hlist_head ports;
+ unsigned long addr;
+ size_t size;
+};
+
+struct port {
+ mach_port_t *p;
+ struct cds_hlist_node node; /* Linked-list chaining */
+};
+
+static uint32_t portseal_seed;
+static struct cds_lfht *portseal_object_hash;
+static int portseal_is_initialized;
+
+/* Reference counting. */
+void
+portseal_increment (mach_port_t p)
+{
+ if (! MACH_PORT_VALID (p))
+ return;
+
+ if (p >= PORTSEAL_PORTS_SIZE)
+ {
+ TRACE ("port name %d >= PORTSEAL_PORTS_SIZE", (int) p);
+ return;
+ }
+
+ TRACE ("portseal_increment (%d)", (int) p);
+ __atomic_add_fetch (&ports[p], 1, __ATOMIC_RELAXED);
+}
+
+static char *mach_port_right_str[] =
+ {
+ "send",
+ "receive",
+ "send-once",
+ "port-set",
+ "dead-name",
+ };
+
+static void
+portseal_dec (mach_port_t p)
+{
+ if (! MACH_PORT_VALID (p))
+ return;
+
+ if (p >= PORTSEAL_PORTS_SIZE)
+ {
+ TRACE ("port name %d >= PORTSEAL_PORTS_SIZE", (int) p);
+ return;
+ }
+
+ int c = __atomic_sub_fetch (&ports[p], 1, __ATOMIC_RELAXED);
+ TRACE ("portseal_decrement (%d) to %d", (int) p, c);
+ if (c > 0)
+ return;
+
+ /* check hurd ports */
+ for (int i = 0; i < INIT_PORT_MAX; i++)
+ if (HURD_PORT_USE (&_hurd_ports[i], port == p))
+ /* the libc has a reference, it's fine */
+ return;
+
+ error_t err = 0;
+ mach_port_urefs_t refs;
+ mach_port_right_t typ;
+
+ for (typ = MACH_PORT_RIGHT_SEND;
+ typ < MACH_PORT_RIGHT_NUMBER;
+ typ++)
+ {
+ err = mach_port_get_refs (mach_task_self (),
+ p,
+ typ,
+ &refs);
+ if (err)
+ goto out;
+ if (refs)
+ goto leak;
+ }
+
+ out:
+ if (err && err != KERN_INVALID_NAME)
+ error (0, err, "error in portseal_check_leak");
+ return;
+
+ leak:
+ error (0, 0, "leaked %s right %d", mach_port_right_str[typ], (int) p);
+ void *array[20];
+ size_t size;
+ size = backtrace (array, 20);
+ backtrace_symbols_fd (&array[2], size - 2, 2);
+}
+
+/* Used as cleanup function when variables with storage class auto,
+ i.e. variables residing on the stack. */
+void
+portseal_decrement_p (mach_port_t *p)
+{
+ portseal_dec (*p);
+}
+
+void
+portseal_decrement (mach_port_t p)
+{
+ portseal_dec (p);
+}
+
+/* Used to wrap port assignments. */
+mach_port_t
+portseal_set_port (mach_port_t *p, mach_port_t new)
+{
+ portseal_dec (*p);
+
+ if (! MACH_PORT_VALID (new))
+ goto out;
+
+ portseal_increment (new);
+
+ struct object *o = NULL, *node;
+ struct cds_lfht_iter iter;
+ rcu_read_lock();
+ cds_lfht_for_each_entry (portseal_object_hash, &iter, node, node)
+ if ((unsigned long) node->addr <= (unsigned long) p
+ && (unsigned long) p < (unsigned long) node->addr + node->size)
+ {
+ o = node;
+ break;
+ }
+ rcu_read_unlock();
+
+ if (o != NULL) {
+ TRACE ("set port in object %p", (void *) o->addr);
+ struct port *port = malloc (sizeof *port);
+ if (port) {
+ port->p = p;
+ cds_hlist_add_head_rcu (&port->node, &o->ports);
+ }
+ }
+
+ out:
+ return new;
+}
+
+/* Memory management. */
+void *
+portseal_malloc (size_t size)
+{
+ struct object *o;
+ posix_memalign ((void **) &o, 8, size + sizeof (struct object));
+ if (! o)
+ return NULL;
+
+ void *p = o + sizeof (struct object);
+
+ cds_lfht_node_init (&o->node);
+ CDS_INIT_HLIST_HEAD (&o->ports);
+ o->addr = (unsigned long) p;
+ o->size = size;
+ unsigned long hash = jhash (&p, sizeof p, portseal_seed);
+ rcu_read_lock ();
+ cds_lfht_add (portseal_object_hash, hash, &o->node);
+ rcu_read_unlock ();
+
+ return p;
+}
+
+static void
+free_object (struct rcu_head *head)
+{
+ struct object *node = caa_container_of (head, struct object, rcu_head);
+ TRACE ("free_object(%p)", node);
+ free (node);
+}
+
+static int
+match (struct cds_lfht_node *ht_node, const void *_key)
+{
+ struct object *o =
+ caa_container_of(ht_node, struct object, node);
+ const unsigned long *key = _key;
+
+ return *key == o->addr;
+}
+
+void
+portseal_free (void *p)
+{
+ TRACE ("free(%p)", p);
+
+ unsigned long hash = jhash (&p, sizeof p, portseal_seed);
+ rcu_read_lock ();
+ struct cds_lfht_iter iter;
+ cds_lfht_lookup (portseal_object_hash, hash, match, &p, &iter);
+ struct cds_lfht_node *ht_node = cds_lfht_iter_get_node (&iter);
+ if (ht_node)
+ {
+ if (! cds_lfht_del (portseal_object_hash, ht_node))
+ {
+ struct object *del_node =
+ caa_container_of (ht_node,
+ struct object, node);
+
+ struct port *port;
+ struct cds_hlist_node *pos;
+ cds_hlist_for_each_entry (port, pos, &del_node->ports, node) {
+ portseal_decrement (*port->p);
+ *port->p = MACH_PORT_NULL;
+ free (port);
+ }
+
+ call_rcu (&del_node->rcu_head, free_object);
+ }
+ }
+ rcu_read_unlock ();
+}
+
+/* Initialization and teardown. */
+
+static void __attribute__ ((constructor))
+portseal_init ()
+{
+ portseal_object_hash = cds_lfht_new(1, 1, 0,
+ CDS_LFHT_AUTO_RESIZE | CDS_LFHT_ACCOUNTING,
+ NULL);
+ if (! portseal_object_hash)
+ error (1, errno, "Error allocating hash table");
+
+ portseal_seed = (uint32_t) time (NULL);
+ rcu_register_thread ();
+
+ portseal_is_initialized = 1;
+}
+
+static void __attribute__ ((destructor))
+portseal_destroy () {
+ rcu_unregister_thread ();
+}
diff --git a/libportseal/portseal.h b/libportseal/portseal.h
new file mode 100644
index 0000000..5ad06b0
--- /dev/null
+++ b/libportseal/portseal.h
@@ -0,0 +1,73 @@
+#ifndef __PORTSEAL__
+#define __PORTSEAL__
+
+#define _GNU_SOURCE
+#include <mach.h>
+#include <stddef.h>
+
+extern int ports[];
+
+void *portseal_malloc (size_t) __attribute__ ((malloc));
+void portseal_free (void *);
+
+mach_port_t portseal_set_port (mach_port_t *, mach_port_t);
+void portseal_decrement (mach_port_t);
+void portseal_decrement_p (mach_port_t*);
+void portseal_increment (mach_port_t);
+
+#define PORTSEAL_CLEANUP(T, I, V) \
+ __attribute__ ((cleanup (portseal_decrement_p))) T I = V
+#define PORTSEAL_CLEANUP_I(T, I, V, E) \
+ __attribute__ ((cleanup (portseal_decrement_p))) T I = V; \
+ portseal_set_port (&I, E)
+
+#define PORTSEAL_WRAP(F, P) \
+ ({ \
+ mach_port_t *_p = (P); \
+ mach_port_t _old = *_p; \
+ (F); \
+ mach_port_t _new = *_p; \
+ if (_old != _new) \
+ { \
+ portseal_decrement (_old); \
+ portseal_increment (_new); \
+ } \
+ })
+
+#define GCC_VERSION (__GNUC__ * 10000 \
+ + __GNUC_MINOR__ * 100 \
+ + __GNUC_PATCHLEVEL__)
+
+/* Test for GCC >= 34.9 */
+#if GCC_VERSION >= 40900
+/* use __auto_type */
+#define PORTSEAL_WRAP_R(F, P) \
+ ({ \
+ mach_port_t *_p = (P); \
+ mach_port_t _old = *_p; \
+ __auto_type _result = (F); \
+ mach_port_t _new = *_p; \
+ if (_old != _new) \
+ { \
+ portseal_decrement (_old); \
+ portseal_increment (_new); \
+ } \
+ _result; \
+ })
+#else
+#define PORTSEAL_WRAP_R(F, P) \
+ ({ \
+ mach_port_t *_p = (P); \
+ mach_port_t _old = *_p; \
+ typeof (F) _result = (F); \
+ mach_port_t _new = *_p; \
+ if (_old != _new) \
+ { \
+ portseal_decrement (_old); \
+ portseal_increment (_new); \
+ } \
+ _result; \
+ })
+#endif
+
+#endif /* __PORTSEAL__ */
generated by cgit v1.2.3 (git 2.51.0) at 2025-11-13 23:42:20 +0000