Add m-esr52 at 52.6.0

1 files changed, 1143 insertions, 0 deletions

diff --git a/security/nss/lib/base/arena.c b/security/nss/lib/base/arena.c
new file mode 100644
index 000000000..b8e64643d
--- /dev/null
+++ b/security/nss/lib/base/arena.c
@@ -0,0 +1,1143 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * arena.c
+ *
+ * This contains the implementation of NSS's thread-safe arenas.
+ */
+
+#ifndef BASE_H
+#include "base.h"
+#endif /* BASE_H */
+
+#ifdef ARENA_THREADMARK
+#include "prthread.h"
+#endif /* ARENA_THREADMARK */
+
+#include "prlock.h"
+#include "plarena.h"
+
+#include <string.h>
+
+/*
+ * NSSArena
+ *
+ * This is based on NSPR's arena code, but it is threadsafe.
+ *
+ * The public methods relating to this type are:
+ *
+ *  NSSArena_Create  -- constructor
+ *  NSSArena_Destroy
+ *  NSS_ZAlloc
+ *  NSS_ZRealloc
+ *  NSS_ZFreeIf
+ *
+ * The nonpublic methods relating to this type are:
+ *
+ *  nssArena_Create  -- constructor
+ *  nssArena_Destroy
+ *  nssArena_Mark
+ *  nssArena_Release
+ *  nssArena_Unmark
+ *
+ *  nss_ZAlloc
+ *  nss_ZFreeIf
+ *  nss_ZRealloc
+ *
+ * In debug builds, the following calls are available:
+ *
+ *  nssArena_verifyPointer
+ *  nssArena_registerDestructor
+ *  nssArena_deregisterDestructor
+ */
+
+struct NSSArenaStr {
+    PLArenaPool pool;
+    PRLock *lock;
+#ifdef ARENA_THREADMARK
+    PRThread *marking_thread;
+    nssArenaMark *first_mark;
+    nssArenaMark *last_mark;
+#endif /* ARENA_THREADMARK */
+#ifdef ARENA_DESTRUCTOR_LIST
+    struct arena_destructor_node *first_destructor;
+    struct arena_destructor_node *last_destructor;
+#endif /* ARENA_DESTRUCTOR_LIST */
+};
+
+/*
+ * nssArenaMark
+ *
+ * This type is used to mark the current state of an NSSArena.
+ */
+
+struct nssArenaMarkStr {
+    PRUint32 magic;
+    void *mark;
+#ifdef ARENA_THREADMARK
+    nssArenaMark *next;
+#endif /* ARENA_THREADMARK */
+#ifdef ARENA_DESTRUCTOR_LIST
+    struct arena_destructor_node *next_destructor;
+    struct arena_destructor_node *prev_destructor;
+#endif /* ARENA_DESTRUCTOR_LIST */
+};
+
+#define MARK_MAGIC 0x4d41524b /* "MARK" how original */
+
+/*
+ * But first, the pointer-tracking code
+ */
+#ifdef DEBUG
+extern const NSSError NSS_ERROR_INTERNAL_ERROR;
+
+static nssPointerTracker arena_pointer_tracker;
+
+static PRStatus
+arena_add_pointer(const NSSArena *arena)
+{
+    PRStatus rv;
+
+    rv = nssPointerTracker_initialize(&arena_pointer_tracker);
+    if (PR_SUCCESS != rv) {
+        return rv;
+    }
+
+    rv = nssPointerTracker_add(&arena_pointer_tracker, arena);
+    if (PR_SUCCESS != rv) {
+        NSSError e = NSS_GetError();
+        if (NSS_ERROR_NO_MEMORY != e) {
+            nss_SetError(NSS_ERROR_INTERNAL_ERROR);
+        }
+
+        return rv;
+    }
+
+    return PR_SUCCESS;
+}
+
+static PRStatus
+arena_remove_pointer(const NSSArena *arena)
+{
+    PRStatus rv;
+
+    rv = nssPointerTracker_remove(&arena_pointer_tracker, arena);
+    if (PR_SUCCESS != rv) {
+        nss_SetError(NSS_ERROR_INTERNAL_ERROR);
+    }
+
+    return rv;
+}
+
+/*
+ * nssArena_verifyPointer
+ *
+ * This method is only present in debug builds.
+ *
+ * If the specified pointer is a valid pointer to an NSSArena object,
+ * this routine will return PR_SUCCESS.  Otherwise, it will put an
+ * error on the error stack and return PR_FAILURE.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_ARENA
+ *
+ * Return value:
+ *  PR_SUCCESS if the pointer is valid
+ *  PR_FAILURE if it isn't
+ */
+
+NSS_IMPLEMENT PRStatus
+nssArena_verifyPointer(const NSSArena *arena)
+{
+    PRStatus rv;
+
+    rv = nssPointerTracker_initialize(&arena_pointer_tracker);
+    if (PR_SUCCESS != rv) {
+        /*
+         * This is a little disingenious.  We have to initialize the
+         * tracker, because someone could "legitimately" try to verify
+         * an arena pointer before one is ever created.  And this step
+         * might fail, due to lack of memory.  But the only way that
+         * this step can fail is if it's doing the call_once stuff,
+         * (later calls just no-op).  And if it didn't no-op, there
+         * aren't any valid arenas.. so the argument certainly isn't one.
+         */
+        nss_SetError(NSS_ERROR_INVALID_ARENA);
+        return PR_FAILURE;
+    }
+
+    rv = nssPointerTracker_verify(&arena_pointer_tracker, arena);
+    if (PR_SUCCESS != rv) {
+        nss_SetError(NSS_ERROR_INVALID_ARENA);
+        return PR_FAILURE;
+    }
+
+    return PR_SUCCESS;
+}
+#endif /* DEBUG */
+
+#ifdef ARENA_DESTRUCTOR_LIST
+
+struct arena_destructor_node {
+    struct arena_destructor_node *next;
+    struct arena_destructor_node *prev;
+    void (*destructor)(void *argument);
+    void *arg;
+};
+
+/*
+ * nssArena_registerDestructor
+ *
+ * This routine stores a pointer to a callback and an arbitrary
+ * pointer-sized argument in the arena, at the current point in
+ * the mark stack.  If the arena is destroyed, or an "earlier"
+ * mark is released, then this destructor will be called at that
+ * time.  Note that the destructor will be called with the arena
+ * locked, which means the destructor may free memory in that
+ * arena, but it may not allocate or cause to be allocated any
+ * memory.  This callback facility was included to support our
+ * debug-version pointer-tracker feature; overuse runs counter to
+ * the the original intent of arenas.  This routine returns a
+ * PRStatus value; if successful, it will return PR_SUCCESS.  If
+ * unsuccessful, it will set an error on the error stack and
+ * return PR_FAILURE.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_ARENA
+ *  NSS_ERROR_NO_MEMORY
+ *
+ * Return value:
+ *  PR_SUCCESS
+ *  PR_FAILURE
+ */
+
+NSS_IMPLEMENT PRStatus
+nssArena_registerDestructor(NSSArena *arena, void (*destructor)(void *argument),
+                            void *arg)
+{
+    struct arena_destructor_node *it;
+
+#ifdef NSSDEBUG
+    if (PR_SUCCESS != nssArena_verifyPointer(arena)) {
+        return PR_FAILURE;
+    }
+#endif /* NSSDEBUG */
+
+    it = nss_ZNEW(arena, struct arena_destructor_node);
+    if ((struct arena_destructor_node *)NULL == it) {
+        return PR_FAILURE;
+    }
+
+    it->prev = arena->last_destructor;
+    arena->last_destructor->next = it;
+    arena->last_destructor = it;
+    it->destructor = destructor;
+    it->arg = arg;
+
+    if ((nssArenaMark *)NULL != arena->last_mark) {
+        arena->last_mark->prev_destructor = it->prev;
+        arena->last_mark->next_destructor = it->next;
+    }
+
+    return PR_SUCCESS;
+}
+
+NSS_IMPLEMENT PRStatus
+nssArena_deregisterDestructor(NSSArena *arena,
+                              void (*destructor)(void *argument), void *arg)
+{
+    struct arena_destructor_node *it;
+
+#ifdef NSSDEBUG
+    if (PR_SUCCESS != nssArena_verifyPointer(arena)) {
+        return PR_FAILURE;
+    }
+#endif /* NSSDEBUG */
+
+    for (it = arena->first_destructor; it; it = it->next) {
+        if ((it->destructor == destructor) && (it->arg == arg)) {
+            break;
+        }
+    }
+
+    if ((struct arena_destructor_node *)NULL == it) {
+        nss_SetError(NSS_ERROR_NOT_FOUND);
+        return PR_FAILURE;
+    }
+
+    if (it == arena->first_destructor) {
+        arena->first_destructor = it->next;
+    }
+
+    if (it == arena->last_destructor) {
+        arena->last_destructor = it->prev;
+    }
+
+    if ((struct arena_destructor_node *)NULL != it->prev) {
+        it->prev->next = it->next;
+    }
+
+    if ((struct arena_destructor_node *)NULL != it->next) {
+        it->next->prev = it->prev;
+    }
+
+    {
+        nssArenaMark *m;
+        for (m = arena->first_mark; m; m = m->next) {
+            if (m->next_destructor == it) {
+                m->next_destructor = it->next;
+            }
+            if (m->prev_destructor == it) {
+                m->prev_destructor = it->prev;
+            }
+        }
+    }
+
+    nss_ZFreeIf(it);
+    return PR_SUCCESS;
+}
+
+static void
+nss_arena_call_destructor_chain(struct arena_destructor_node *it)
+{
+    for (; it; it = it->next) {
+        (*(it->destructor))(it->arg);
+    }
+}
+
+#endif /* ARENA_DESTRUCTOR_LIST */
+
+/*
+ * NSSArena_Create
+ *
+ * This routine creates a new memory arena.  This routine may return
+ * NULL upon error, in which case it will have created an error stack.
+ *
+ * The top-level error may be one of the following values:
+ *  NSS_ERROR_NO_MEMORY
+ *
+ * Return value:
+ *  NULL upon error
+ *  A pointer to an NSSArena upon success
+ */
+
+NSS_IMPLEMENT NSSArena *
+NSSArena_Create(void)
+{
+    nss_ClearErrorStack();
+    return nssArena_Create();
+}
+
+/*
+ * nssArena_Create
+ *
+ * This routine creates a new memory arena.  This routine may return
+ * NULL upon error, in which case it will have set an error on the
+ * error stack.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_NO_MEMORY
+ *
+ * Return value:
+ *  NULL upon error
+ *  A pointer to an NSSArena upon success
+ */
+
+NSS_IMPLEMENT NSSArena *
+nssArena_Create(void)
+{
+    NSSArena *rv = (NSSArena *)NULL;
+
+    rv = nss_ZNEW((NSSArena *)NULL, NSSArena);
+    if ((NSSArena *)NULL == rv) {
+        nss_SetError(NSS_ERROR_NO_MEMORY);
+        return (NSSArena *)NULL;
+    }
+
+    rv->lock = PR_NewLock();
+    if ((PRLock *)NULL == rv->lock) {
+        (void)nss_ZFreeIf(rv);
+        nss_SetError(NSS_ERROR_NO_MEMORY);
+        return (NSSArena *)NULL;
+    }
+
+    /*
+     * Arena sizes.  The current security code has 229 occurrences of
+     * PORT_NewArena.  The default chunksizes specified break down as
+     *
+     *  Size    Mult.   Specified as
+     *   512       1    512
+     *  1024       7    1024
+     *  2048       5    2048
+     *  2048       5    CRMF_DEFAULT_ARENA_SIZE
+     *  2048     190    DER_DEFAULT_CHUNKSIZE
+     *  2048      20    SEC_ASN1_DEFAULT_ARENA_SIZE
+     *  4096       1    4096
+     *
+     * Obviously this "default chunksize" flexibility isn't very
+     * useful to us, so I'll just pick 2048.
+     */
+
+    PL_InitArenaPool(&rv->pool, "NSS", 2048, sizeof(double));
+
+#ifdef DEBUG
+    {
+        PRStatus st;
+        st = arena_add_pointer(rv);
+        if (PR_SUCCESS != st) {
+            PL_FinishArenaPool(&rv->pool);
+            PR_DestroyLock(rv->lock);
+            (void)nss_ZFreeIf(rv);
+            return (NSSArena *)NULL;
+        }
+    }
+#endif /* DEBUG */
+
+    return rv;
+}
+
+/*
+ * NSSArena_Destroy
+ *
+ * This routine will destroy the specified arena, freeing all memory
+ * allocated from it.  This routine returns a PRStatus value; if
+ * successful, it will return PR_SUCCESS.  If unsuccessful, it will
+ * create an error stack and return PR_FAILURE.
+ *
+ * The top-level error may be one of the following values:
+ *  NSS_ERROR_INVALID_ARENA
+ *
+ * Return value:
+ *  PR_SUCCESS upon success
+ *  PR_FAILURE upon failure
+ */
+
+NSS_IMPLEMENT PRStatus
+NSSArena_Destroy(NSSArena *arena)
+{
+    nss_ClearErrorStack();
+
+#ifdef DEBUG
+    if (PR_SUCCESS != nssArena_verifyPointer(arena)) {
+        return PR_FAILURE;
+    }
+#endif /* DEBUG */
+
+    return nssArena_Destroy(arena);
+}
+
+/*
+ * nssArena_Destroy
+ *
+ * This routine will destroy the specified arena, freeing all memory
+ * allocated from it.  This routine returns a PRStatus value; if
+ * successful, it will return PR_SUCCESS.  If unsuccessful, it will
+ * set an error on the error stack and return PR_FAILURE.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_ARENA
+ *
+ * Return value:
+ *  PR_SUCCESS
+ *  PR_FAILURE
+ */
+
+NSS_IMPLEMENT PRStatus
+nssArena_Destroy(NSSArena *arena)
+{
+    PRLock *lock;
+
+#ifdef NSSDEBUG
+    if (PR_SUCCESS != nssArena_verifyPointer(arena)) {
+        return PR_FAILURE;
+    }
+#endif /* NSSDEBUG */
+
+    if ((PRLock *)NULL == arena->lock) {
+        /* Just got destroyed */
+        nss_SetError(NSS_ERROR_INVALID_ARENA);
+        return PR_FAILURE;
+    }
+    PR_Lock(arena->lock);
+
+#ifdef DEBUG
+    if (PR_SUCCESS != arena_remove_pointer(arena)) {
+        PR_Unlock(arena->lock);
+        return PR_FAILURE;
+    }
+#endif /* DEBUG */
+
+#ifdef ARENA_DESTRUCTOR_LIST
+    /* Note that the arena is locked at this time */
+    nss_arena_call_destructor_chain(arena->first_destructor);
+#endif /* ARENA_DESTRUCTOR_LIST */
+
+    PL_FinishArenaPool(&arena->pool);
+    lock = arena->lock;
+    arena->lock = (PRLock *)NULL;
+    PR_Unlock(lock);
+    PR_DestroyLock(lock);
+    (void)nss_ZFreeIf(arena);
+    return PR_SUCCESS;
+}
+
+static void *nss_zalloc_arena_locked(NSSArena *arena, PRUint32 size);
+
+/*
+ * nssArena_Mark
+ *
+ * This routine "marks" the current state of an arena.  Space
+ * allocated after the arena has been marked can be freed by
+ * releasing the arena back to the mark with nssArena_Release,
+ * or committed by calling nssArena_Unmark.  When successful,
+ * this routine returns a valid nssArenaMark pointer.  This
+ * routine may return NULL upon error, in which case it will
+ * have set an error on the error stack.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_ARENA
+ *  NSS_ERROR_NO_MEMORY
+ *  NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD
+ *
+ * Return value:
+ *  NULL upon failure
+ *  An nssArenaMark pointer upon success
+ */
+
+NSS_IMPLEMENT nssArenaMark *
+nssArena_Mark(NSSArena *arena)
+{
+    nssArenaMark *rv;
+    void *p;
+
+#ifdef NSSDEBUG
+    if (PR_SUCCESS != nssArena_verifyPointer(arena)) {
+        return (nssArenaMark *)NULL;
+    }
+#endif /* NSSDEBUG */
+
+    if ((PRLock *)NULL == arena->lock) {
+        /* Just got destroyed */
+        nss_SetError(NSS_ERROR_INVALID_ARENA);
+        return (nssArenaMark *)NULL;
+    }
+    PR_Lock(arena->lock);
+
+#ifdef ARENA_THREADMARK
+    if ((PRThread *)NULL == arena->marking_thread) {
+        /* Unmarked.  Store our thread ID */
+        arena->marking_thread = PR_GetCurrentThread();
+        /* This call never fails. */
+    } else {
+        /* Marked.  Verify it's the current thread */
+        if (PR_GetCurrentThread() != arena->marking_thread) {
+            PR_Unlock(arena->lock);
+            nss_SetError(NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD);
+            return (nssArenaMark *)NULL;
+        }
+    }
+#endif /* ARENA_THREADMARK */
+
+    p = PL_ARENA_MARK(&arena->pool);
+    /* No error possible */
+
+    /* Do this after the mark */
+    rv = (nssArenaMark *)nss_zalloc_arena_locked(arena, sizeof(nssArenaMark));
+    if ((nssArenaMark *)NULL == rv) {
+        PR_Unlock(arena->lock);
+        nss_SetError(NSS_ERROR_NO_MEMORY);
+        return (nssArenaMark *)NULL;
+    }
+
+#ifdef ARENA_THREADMARK
+    if ((nssArenaMark *)NULL == arena->first_mark) {
+        arena->first_mark = rv;
+        arena->last_mark = rv;
+    } else {
+        arena->last_mark->next = rv;
+        arena->last_mark = rv;
+    }
+#endif /* ARENA_THREADMARK */
+
+    rv->mark = p;
+    rv->magic = MARK_MAGIC;
+
+#ifdef ARENA_DESTRUCTOR_LIST
+    rv->prev_destructor = arena->last_destructor;
+#endif /* ARENA_DESTRUCTOR_LIST */
+
+    PR_Unlock(arena->lock);
+
+    return rv;
+}
+
+/*
+ * nss_arena_unmark_release
+ *
+ * This static routine implements the routines nssArena_Release
+ * ans nssArena_Unmark, which are almost identical.
+ */
+
+static PRStatus
+nss_arena_unmark_release(NSSArena *arena, nssArenaMark *arenaMark,
+                         PRBool release)
+{
+    void *inner_mark;
+
+#ifdef NSSDEBUG
+    if (PR_SUCCESS != nssArena_verifyPointer(arena)) {
+        return PR_FAILURE;
+    }
+#endif /* NSSDEBUG */
+
+    if (MARK_MAGIC != arenaMark->magic) {
+        nss_SetError(NSS_ERROR_INVALID_ARENA_MARK);
+        return PR_FAILURE;
+    }
+
+    if ((PRLock *)NULL == arena->lock) {
+        /* Just got destroyed */
+        nss_SetError(NSS_ERROR_INVALID_ARENA);
+        return PR_FAILURE;
+    }
+    PR_Lock(arena->lock);
+
+#ifdef ARENA_THREADMARK
+    if ((PRThread *)NULL != arena->marking_thread) {
+        if (PR_GetCurrentThread() != arena->marking_thread) {
+            PR_Unlock(arena->lock);
+            nss_SetError(NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD);
+            return PR_FAILURE;
+        }
+    }
+#endif /* ARENA_THREADMARK */
+
+    if (MARK_MAGIC != arenaMark->magic) {
+        /* Just got released */
+        PR_Unlock(arena->lock);
+        nss_SetError(NSS_ERROR_INVALID_ARENA_MARK);
+        return PR_FAILURE;
+    }
+
+    arenaMark->magic = 0;
+    inner_mark = arenaMark->mark;
+
+#ifdef ARENA_THREADMARK
+    {
+        nssArenaMark **pMark = &arena->first_mark;
+        nssArenaMark *rest;
+        nssArenaMark *last = (nssArenaMark *)NULL;
+
+        /* Find this mark */
+        while (*pMark != arenaMark) {
+            last = *pMark;
+            pMark = &(*pMark)->next;
+        }
+
+        /* Remember the pointer, then zero it */
+        rest = (*pMark)->next;
+        *pMark = (nssArenaMark *)NULL;
+
+        arena->last_mark = last;
+
+        /* Invalidate any later marks being implicitly released */
+        for (; (nssArenaMark *)NULL != rest; rest = rest->next) {
+            rest->magic = 0;
+        }
+
+        /* If we just got rid of the first mark, clear the thread ID */
+        if ((nssArenaMark *)NULL == arena->first_mark) {
+            arena->marking_thread = (PRThread *)NULL;
+        }
+    }
+#endif /* ARENA_THREADMARK */
+
+    if (release) {
+#ifdef ARENA_DESTRUCTOR_LIST
+        if ((struct arena_destructor_node *)NULL !=
+            arenaMark->prev_destructor) {
+            arenaMark->prev_destructor->next =
+                (struct arena_destructor_node *)NULL;
+        }
+        arena->last_destructor = arenaMark->prev_destructor;
+
+        /* Note that the arena is locked at this time */
+        nss_arena_call_destructor_chain(arenaMark->next_destructor);
+#endif /* ARENA_DESTRUCTOR_LIST */
+
+        PL_ARENA_RELEASE(&arena->pool, inner_mark);
+        /* No error return */
+    }
+
+    PR_Unlock(arena->lock);
+    return PR_SUCCESS;
+}
+
+/*
+ * nssArena_Release
+ *
+ * This routine invalidates and releases all memory allocated from
+ * the specified arena after the point at which the specified mark
+ * was obtained.  This routine returns a PRStatus value; if successful,
+ * it will return PR_SUCCESS.  If unsuccessful, it will set an error
+ * on the error stack and return PR_FAILURE.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_ARENA
+ *  NSS_ERROR_INVALID_ARENA_MARK
+ *  NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD
+ *
+ * Return value:
+ *  PR_SUCCESS
+ *  PR_FAILURE
+ */
+
+NSS_IMPLEMENT PRStatus
+nssArena_Release(NSSArena *arena, nssArenaMark *arenaMark)
+{
+    return nss_arena_unmark_release(arena, arenaMark, PR_TRUE);
+}
+
+/*
+ * nssArena_Unmark
+ *
+ * This routine "commits" the indicated mark and any marks after
+ * it, making them unreleasable.  Note that any earlier marks can
+ * still be released, and such a release will invalidate these
+ * later unmarked regions.  If an arena is to be safely shared by
+ * more than one thread, all marks must be either released or
+ * unmarked.  This routine returns a PRStatus value; if successful,
+ * it will return PR_SUCCESS.  If unsuccessful, it will set an error
+ * on the error stack and return PR_FAILURE.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_ARENA
+ *  NSS_ERROR_INVALID_ARENA_MARK
+ *  NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD
+ *
+ * Return value:
+ *  PR_SUCCESS
+ *  PR_FAILURE
+ */
+
+NSS_IMPLEMENT PRStatus
+nssArena_Unmark(NSSArena *arena, nssArenaMark *arenaMark)
+{
+    return nss_arena_unmark_release(arena, arenaMark, PR_FALSE);
+}
+
+/*
+ * We prefix this header to all allocated blocks.  It is a multiple
+ * of the alignment size.  Note that this usage of a header may make
+ * purify spew bogus warnings about "potentially leaked blocks" of
+ * memory; if that gets too annoying we can add in a pointer to the
+ * header in the header itself.  There's not a lot of safety here;
+ * maybe we should add a magic value?
+ */
+struct pointer_header {
+    NSSArena *arena;
+    PRUint32 size;
+};
+
+static void *
+nss_zalloc_arena_locked(NSSArena *arena, PRUint32 size)
+{
+    void *p;
+    void *rv;
+    struct pointer_header *h;
+    PRUint32 my_size = size + sizeof(struct pointer_header);
+    PL_ARENA_ALLOCATE(p, &arena->pool, my_size);
+    if ((void *)NULL == p) {
+        nss_SetError(NSS_ERROR_NO_MEMORY);
+        return (void *)NULL;
+    }
+    /*
+     * Do this before we unlock.  This way if the user is using
+     * an arena in one thread while destroying it in another, he'll
+     * fault/FMR in his code, not ours.
+     */
+    h = (struct pointer_header *)p;
+    h->arena = arena;
+    h->size = size;
+    rv = (void *)((char *)h + sizeof(struct pointer_header));
+    (void)nsslibc_memset(rv, 0, size);
+    return rv;
+}
+
+/*
+ * NSS_ZAlloc
+ *
+ * This routine allocates and zeroes a section of memory of the
+ * size, and returns to the caller a pointer to that memory.  If
+ * the optional arena argument is non-null, the memory will be
+ * obtained from that arena; otherwise, the memory will be obtained
+ * from the heap.  This routine may return NULL upon error, in
+ * which case it will have set an error upon the error stack.  The
+ * value specified for size may be zero; in which case a valid
+ * zero-length block of memory will be allocated.  This block may
+ * be expanded by calling NSS_ZRealloc.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_ARENA
+ *  NSS_ERROR_NO_MEMORY
+ *  NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD
+ *
+ * Return value:
+ *  NULL upon error
+ *  A pointer to the new segment of zeroed memory
+ */
+
+NSS_IMPLEMENT void *
+NSS_ZAlloc(NSSArena *arenaOpt, PRUint32 size)
+{
+    return nss_ZAlloc(arenaOpt, size);
+}
+
+/*
+ * nss_ZAlloc
+ *
+ * This routine allocates and zeroes a section of memory of the
+ * size, and returns to the caller a pointer to that memory.  If
+ * the optional arena argument is non-null, the memory will be
+ * obtained from that arena; otherwise, the memory will be obtained
+ * from the heap.  This routine may return NULL upon error, in
+ * which case it will have set an error upon the error stack.  The
+ * value specified for size may be zero; in which case a valid
+ * zero-length block of memory will be allocated.  This block may
+ * be expanded by calling nss_ZRealloc.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_ARENA
+ *  NSS_ERROR_NO_MEMORY
+ *  NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD
+ *
+ * Return value:
+ *  NULL upon error
+ *  A pointer to the new segment of zeroed memory
+ */
+
+NSS_IMPLEMENT void *
+nss_ZAlloc(NSSArena *arenaOpt, PRUint32 size)
+{
+    struct pointer_header *h;
+    PRUint32 my_size = size + sizeof(struct pointer_header);
+
+    if (my_size < sizeof(struct pointer_header)) {
+        /* Wrapped */
+        nss_SetError(NSS_ERROR_NO_MEMORY);
+        return (void *)NULL;
+    }
+
+    if ((NSSArena *)NULL == arenaOpt) {
+        /* Heap allocation, no locking required. */
+        h = (struct pointer_header *)PR_Calloc(1, my_size);
+        if ((struct pointer_header *)NULL == h) {
+            nss_SetError(NSS_ERROR_NO_MEMORY);
+            return (void *)NULL;
+        }
+
+        h->arena = (NSSArena *)NULL;
+        h->size = size;
+        /* We used calloc: it's already zeroed */
+
+        return (void *)((char *)h + sizeof(struct pointer_header));
+    } else {
+        void *rv;
+/* Arena allocation */
+#ifdef NSSDEBUG
+        if (PR_SUCCESS != nssArena_verifyPointer(arenaOpt)) {
+            return (void *)NULL;
+        }
+#endif /* NSSDEBUG */
+
+        if ((PRLock *)NULL == arenaOpt->lock) {
+            /* Just got destroyed */
+            nss_SetError(NSS_ERROR_INVALID_ARENA);
+            return (void *)NULL;
+        }
+        PR_Lock(arenaOpt->lock);
+
+#ifdef ARENA_THREADMARK
+        if ((PRThread *)NULL != arenaOpt->marking_thread) {
+            if (PR_GetCurrentThread() != arenaOpt->marking_thread) {
+                nss_SetError(NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD);
+                PR_Unlock(arenaOpt->lock);
+                return (void *)NULL;
+            }
+        }
+#endif /* ARENA_THREADMARK */
+
+        rv = nss_zalloc_arena_locked(arenaOpt, size);
+
+        PR_Unlock(arenaOpt->lock);
+        return rv;
+    }
+    /*NOTREACHED*/
+}
+
+/*
+ * NSS_ZFreeIf
+ *
+ * If the specified pointer is non-null, then the region of memory
+ * to which it points -- which must have been allocated with
+ * NSS_ZAlloc -- will be zeroed and released.  This routine
+ * returns a PRStatus value; if successful, it will return PR_SUCCESS.
+ * If unsuccessful, it will set an error on the error stack and return
+ * PR_FAILURE.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_POINTER
+ *
+ * Return value:
+ *  PR_SUCCESS
+ *  PR_FAILURE
+ */
+NSS_IMPLEMENT PRStatus
+NSS_ZFreeIf(void *pointer)
+{
+    return nss_ZFreeIf(pointer);
+}
+
+/*
+ * nss_ZFreeIf
+ *
+ * If the specified pointer is non-null, then the region of memory
+ * to which it points -- which must have been allocated with
+ * nss_ZAlloc -- will be zeroed and released.  This routine
+ * returns a PRStatus value; if successful, it will return PR_SUCCESS.
+ * If unsuccessful, it will set an error on the error stack and return
+ * PR_FAILURE.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_POINTER
+ *
+ * Return value:
+ *  PR_SUCCESS
+ *  PR_FAILURE
+ */
+
+NSS_IMPLEMENT PRStatus
+nss_ZFreeIf(void *pointer)
+{
+    struct pointer_header *h;
+
+    if ((void *)NULL == pointer) {
+        return PR_SUCCESS;
+    }
+
+    h = (struct pointer_header *)((char *)pointer -
+                                  sizeof(struct pointer_header));
+
+    /* Check any magic here */
+
+    if ((NSSArena *)NULL == h->arena) {
+        /* Heap */
+        (void)nsslibc_memset(pointer, 0, h->size);
+        PR_Free(h);
+        return PR_SUCCESS;
+    } else {
+/* Arena */
+#ifdef NSSDEBUG
+        if (PR_SUCCESS != nssArena_verifyPointer(h->arena)) {
+            return PR_FAILURE;
+        }
+#endif /* NSSDEBUG */
+
+        if ((PRLock *)NULL == h->arena->lock) {
+            /* Just got destroyed.. so this pointer is invalid */
+            nss_SetError(NSS_ERROR_INVALID_POINTER);
+            return PR_FAILURE;
+        }
+        PR_Lock(h->arena->lock);
+
+        (void)nsslibc_memset(pointer, 0, h->size);
+
+        /* No way to "free" it within an NSPR arena. */
+
+        PR_Unlock(h->arena->lock);
+        return PR_SUCCESS;
+    }
+    /*NOTREACHED*/
+}
+
+/*
+ * NSS_ZRealloc
+ *
+ * This routine reallocates a block of memory obtained by calling
+ * nss_ZAlloc or nss_ZRealloc.  The portion of memory
+ * between the new and old sizes -- which is either being newly
+ * obtained or released -- is in either case zeroed.  This routine
+ * may return NULL upon failure, in which case it will have placed
+ * an error on the error stack.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_POINTER
+ *  NSS_ERROR_NO_MEMORY
+ *  NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD
+ *
+ * Return value:
+ *  NULL upon error
+ *  A pointer to the replacement segment of memory
+ */
+
+NSS_EXTERN void *
+NSS_ZRealloc(void *pointer, PRUint32 newSize)
+{
+    return nss_ZRealloc(pointer, newSize);
+}
+
+/*
+ * nss_ZRealloc
+ *
+ * This routine reallocates a block of memory obtained by calling
+ * nss_ZAlloc or nss_ZRealloc.  The portion of memory
+ * between the new and old sizes -- which is either being newly
+ * obtained or released -- is in either case zeroed.  This routine
+ * may return NULL upon failure, in which case it will have placed
+ * an error on the error stack.
+ *
+ * The error may be one of the following values:
+ *  NSS_ERROR_INVALID_POINTER
+ *  NSS_ERROR_NO_MEMORY
+ *  NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD
+ *
+ * Return value:
+ *  NULL upon error
+ *  A pointer to the replacement segment of memory
+ */
+
+NSS_EXTERN void *
+nss_ZRealloc(void *pointer, PRUint32 newSize)
+{
+    NSSArena *arena;
+    struct pointer_header *h, *new_h;
+    PRUint32 my_newSize = newSize + sizeof(struct pointer_header);
+    void *rv;
+
+    if (my_newSize < sizeof(struct pointer_header)) {
+        /* Wrapped */
+        nss_SetError(NSS_ERROR_NO_MEMORY);
+        return (void *)NULL;
+    }
+
+    if ((void *)NULL == pointer) {
+        nss_SetError(NSS_ERROR_INVALID_POINTER);
+        return (void *)NULL;
+    }
+
+    h = (struct pointer_header *)((char *)pointer -
+                                  sizeof(struct pointer_header));
+
+    /* Check any magic here */
+
+    if (newSize == h->size) {
+        /* saves thrashing */
+        return pointer;
+    }
+
+    arena = h->arena;
+    if (!arena) {
+        /* Heap */
+        new_h = (struct pointer_header *)PR_Calloc(1, my_newSize);
+        if ((struct pointer_header *)NULL == new_h) {
+            nss_SetError(NSS_ERROR_NO_MEMORY);
+            return (void *)NULL;
+        }
+
+        new_h->arena = (NSSArena *)NULL;
+        new_h->size = newSize;
+        rv = (void *)((char *)new_h + sizeof(struct pointer_header));
+
+        if (newSize > h->size) {
+            (void)nsslibc_memcpy(rv, pointer, h->size);
+            (void)nsslibc_memset(&((char *)rv)[h->size], 0,
+                                 (newSize - h->size));
+        } else {
+            (void)nsslibc_memcpy(rv, pointer, newSize);
+        }
+
+        (void)nsslibc_memset(pointer, 0, h->size);
+        h->size = 0;
+        PR_Free(h);
+
+        return rv;
+    } else {
+        void *p;
+/* Arena */
+#ifdef NSSDEBUG
+        if (PR_SUCCESS != nssArena_verifyPointer(arena)) {
+            return (void *)NULL;
+        }
+#endif /* NSSDEBUG */
+
+        if (!arena->lock) {
+            /* Just got destroyed.. so this pointer is invalid */
+            nss_SetError(NSS_ERROR_INVALID_POINTER);
+            return (void *)NULL;
+        }
+        PR_Lock(arena->lock);
+
+#ifdef ARENA_THREADMARK
+        if (arena->marking_thread) {
+            if (PR_GetCurrentThread() != arena->marking_thread) {
+                PR_Unlock(arena->lock);
+                nss_SetError(NSS_ERROR_ARENA_MARKED_BY_ANOTHER_THREAD);
+                return (void *)NULL;
+            }
+        }
+#endif /* ARENA_THREADMARK */
+
+        if (newSize < h->size) {
+            /*
+             * We have no general way of returning memory to the arena
+             * (mark/release doesn't work because things may have been
+             * allocated after this object), so the memory is gone
+             * anyway.  We might as well just return the same pointer to
+             * the user, saying "yeah, uh-hunh, you can only use less of
+             * it now."  We'll zero the leftover part, of course.  And
+             * in fact we might as well *not* adjust h->size-- this way,
+             * if the user reallocs back up to something not greater than
+             * the original size, then voila, there's the memory!  This
+             * way a thrash big/small/big/small doesn't burn up the arena.
+             */
+            char *extra = &((char *)pointer)[newSize];
+            (void)nsslibc_memset(extra, 0, (h->size - newSize));
+            PR_Unlock(arena->lock);
+            return pointer;
+        }
+
+        PL_ARENA_ALLOCATE(p, &arena->pool, my_newSize);
+        if ((void *)NULL == p) {
+            PR_Unlock(arena->lock);
+            nss_SetError(NSS_ERROR_NO_MEMORY);
+            return (void *)NULL;
+        }
+
+        new_h = (struct pointer_header *)p;
+        new_h->arena = arena;
+        new_h->size = newSize;
+        rv = (void *)((char *)new_h + sizeof(struct pointer_header));
+        if (rv != pointer) {
+            (void)nsslibc_memcpy(rv, pointer, h->size);
+            (void)nsslibc_memset(pointer, 0, h->size);
+        }
+        (void)nsslibc_memset(&((char *)rv)[h->size], 0, (newSize - h->size));
+        h->arena = (NSSArena *)NULL;
+        h->size = 0;
+        PR_Unlock(arena->lock);
+        return rv;
+    }
+    /*NOTREACHED*/
+}
+
+PRStatus
+nssArena_Shutdown(void)
+{
+    PRStatus rv = PR_SUCCESS;
+#ifdef DEBUG
+    rv = nssPointerTracker_finalize(&arena_pointer_tracker);
+#endif
+    return rv;
+}