lazy-expunge-plugin.c revision eb453ada41017805a07c24e3d0eaad5af6b7dddf
/* Copyright (c) 2006-2010 Dovecot authors, see the included COPYING file */
#include "lib.h"
#include "ioloop.h"
#include "array.h"
#include "str.h"
#include "seq-range-array.h"
#include "mkdir-parents.h"
#include "mail-storage-private.h"
#include "mail-search-build.h"
#include "mailbox-list-private.h"
#include "mail-namespace.h"
#include "lazy-expunge-plugin.h"
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <dirent.h>
#include <time.h>
#define LAZY_EXPUNGE_CONTEXT(obj) \
MODULE_CONTEXT(obj, lazy_expunge_mail_storage_module)
#define LAZY_EXPUNGE_LIST_CONTEXT(obj) \
MODULE_CONTEXT(obj, lazy_expunge_mailbox_list_module)
#define LAZY_EXPUNGE_USER_CONTEXT(obj) \
MODULE_CONTEXT(obj, lazy_expunge_mail_user_module)
#define LAZY_EXPUNGE_MAIL_CONTEXT(obj) \
MODULE_CONTEXT(obj, lazy_expunge_mail_module)
enum lazy_namespace {
LAZY_NAMESPACE_EXPUNGE,
LAZY_NAMESPACE_DELETE,
LAZY_NAMESPACE_DELETE_EXPUNGE,
LAZY_NAMESPACE_COUNT
};
struct lazy_expunge_mail_user {
union mail_user_module_context module_ctx;
struct mail_namespace *lazy_ns[LAZY_NAMESPACE_COUNT];
const char *env;
};
struct lazy_expunge_mailbox_list {
union mailbox_list_module_context module_ctx;
unsigned int allow_rename:1;
unsigned int internal_namespace:1;
};
struct lazy_expunge_transaction {
union mailbox_transaction_module_context module_ctx;
struct mailbox *dest_box;
struct mailbox_transaction_context *dest_trans;
bool failed;
};
const char *lazy_expunge_plugin_version = DOVECOT_VERSION;
static MODULE_CONTEXT_DEFINE_INIT(lazy_expunge_mail_storage_module,
&mail_storage_module_register);
static MODULE_CONTEXT_DEFINE_INIT(lazy_expunge_mail_module,
&mail_module_register);
static MODULE_CONTEXT_DEFINE_INIT(lazy_expunge_mailbox_list_module,
&mailbox_list_module_register);
static MODULE_CONTEXT_DEFINE_INIT(lazy_expunge_mail_user_module,
&mail_user_module_register);
static struct mailbox *
mailbox_open_or_create(struct mailbox_list *list, const char *name,
const char **error_r)
{
struct mailbox *box;
enum mail_error error;
box = mailbox_alloc(list, name, MAILBOX_FLAG_KEEP_RECENT |
MAILBOX_FLAG_NO_INDEX_FILES);
if (mailbox_open(box) == 0) {
*error_r = NULL;
return box;
}
*error_r = mail_storage_get_last_error(mailbox_get_storage(box),
&error);
if (error != MAIL_ERROR_NOTFOUND) {
mailbox_free(&box);
return NULL;
}
/* try creating and re-opening it. */
if (mailbox_create(box, NULL, FALSE) < 0 ||
mailbox_open(box) < 0) {
*error_r = mail_storage_get_last_error(mailbox_get_storage(box),
NULL);
mailbox_free(&box);
return NULL;
}
return box;
}
static struct mail_namespace *
get_lazy_ns(struct mail_user *user, enum lazy_namespace type)
{
struct lazy_expunge_mail_user *luser = LAZY_EXPUNGE_USER_CONTEXT(user);
return luser->lazy_ns[type];
}
static void lazy_expunge_mail_expunge(struct mail *_mail)
{
struct mail_namespace *ns = _mail->box->list->ns;
struct mail_private *mail = (struct mail_private *)_mail;
union mail_module_context *mmail = LAZY_EXPUNGE_MAIL_CONTEXT(mail);
struct lazy_expunge_transaction *lt =
LAZY_EXPUNGE_CONTEXT(_mail->transaction);
struct mail_namespace *dest_ns;
struct mail_save_context *save_ctx;
const char *error;
dest_ns = get_lazy_ns(ns->user, LAZY_NAMESPACE_EXPUNGE);
if (lt->dest_box == NULL) {
lt->dest_box = mailbox_open_or_create(dest_ns->list,
_mail->box->name, &error);
if (lt->dest_box == NULL) {
mail_storage_set_critical(_mail->box->storage,
"lazy_expunge: Couldn't open expunge mailbox: "
"%s", error);
lt->failed = TRUE;
return;
}
if (mailbox_sync(lt->dest_box, 0) < 0) {
mail_storage_set_critical(_mail->box->storage,
"lazy_expunge: Couldn't sync expunge mailbox");
mailbox_free(&lt->dest_box);
lt->failed = TRUE;
return;
}
lt->dest_trans = mailbox_transaction_begin(lt->dest_box,
MAILBOX_TRANSACTION_FLAG_EXTERNAL);
}
save_ctx = mailbox_save_alloc(lt->dest_trans);
mailbox_save_copy_flags(save_ctx, _mail);
save_ctx->flags &= ~MAIL_DELETED;
if (mailbox_copy(&save_ctx, _mail) < 0 && !_mail->expunged)
lt->failed = TRUE;
mmail->super.expunge(_mail);
}
static struct mailbox_transaction_context *
lazy_expunge_transaction_begin(struct mailbox *box,
enum mailbox_transaction_flags flags)
{
union mailbox_module_context *mbox = LAZY_EXPUNGE_CONTEXT(box);
struct mailbox_transaction_context *t;
struct lazy_expunge_transaction *lt;
t = mbox->super.transaction_begin(box, flags);
lt = i_new(struct lazy_expunge_transaction, 1);
MODULE_CONTEXT_SET(t, lazy_expunge_mail_storage_module, lt);
return t;
}
static void lazy_expunge_transaction_free(struct lazy_expunge_transaction *lt)
{
if (lt->dest_trans != NULL)
mailbox_transaction_rollback(&lt->dest_trans);
if (lt->dest_box != NULL)
mailbox_free(&lt->dest_box);
i_free(lt);
}
static int
lazy_expunge_transaction_commit(struct mailbox_transaction_context *ctx,
struct mail_transaction_commit_changes *changes_r)
{
union mailbox_module_context *mbox = LAZY_EXPUNGE_CONTEXT(ctx->box);
struct lazy_expunge_transaction *lt = LAZY_EXPUNGE_CONTEXT(ctx);
int ret;
if (lt->dest_trans != NULL && !lt->failed) {
if (mailbox_transaction_commit(&lt->dest_trans) < 0)
lt->failed = TRUE;
}
if (lt->failed) {
mbox->super.transaction_rollback(ctx);
ret = -1;
} else {
ret = mbox->super.transaction_commit(ctx, changes_r);
}
lazy_expunge_transaction_free(lt);
return ret;
}
static void
lazy_expunge_transaction_rollback(struct mailbox_transaction_context *ctx)
{
union mailbox_module_context *mbox = LAZY_EXPUNGE_CONTEXT(ctx->box);
struct lazy_expunge_transaction *lt = LAZY_EXPUNGE_CONTEXT(ctx);
mbox->super.transaction_rollback(ctx);
lazy_expunge_transaction_free(lt);
}
static void lazy_expunge_mail_allocated(struct mail *_mail)
{
struct lazy_expunge_transaction *lt =
LAZY_EXPUNGE_CONTEXT(_mail->transaction);
struct mail_private *mail = (struct mail_private *)_mail;
struct mail_vfuncs *v = mail->vlast;
union mail_module_context *mmail;
if (lt == NULL)
return;
mmail = p_new(mail->pool, union mail_module_context, 1);
mmail->super = *v;
mail->vlast = &mmail->super;
v->expunge = lazy_expunge_mail_expunge;
MODULE_CONTEXT_SET_SELF(mail, lazy_expunge_mail_module, mmail);
}
static int
mailbox_move(struct mailbox *src_box, struct mailbox_list *dest_list,
const char *wanted_destname, struct mailbox **dest_box_r)
{
struct lazy_expunge_mailbox_list *src_llist =
LAZY_EXPUNGE_LIST_CONTEXT(src_box->list);
const char *dest_name = wanted_destname;
struct mailbox *dest_box;
const char *dir, *origin;
enum mail_error error;
mode_t mode;
gid_t gid;
int ret;
/* make sure the destination root directory exists */
mailbox_list_get_dir_permissions(dest_list, NULL, &mode, &gid, &origin);
dir = mailbox_list_get_path(dest_list, NULL, MAILBOX_LIST_PATH_TYPE_DIR);
if (mkdir_parents_chgrp(dir, mode, gid, origin) < 0 &&
errno != EEXIST) {
mail_storage_set_critical(src_box->storage,
"mkdir_parents(%s) failed: %m", dir);
return -1;
}
for (;;) {
dest_box = mailbox_alloc(dest_list, dest_name,
MAILBOX_FLAG_OPEN_DELETED);
src_llist->allow_rename = TRUE;
ret = mailbox_rename(src_box, dest_box, FALSE);
src_llist->allow_rename = FALSE;
if (ret == 0)
break;
mailbox_free(&dest_box);
mail_storage_get_last_error(src_box->storage, &error);
switch (error) {
case MAIL_ERROR_EXISTS:
break;
case MAIL_ERROR_NOTFOUND:
return 0;
default:
return -1;
}
/* destination already exists. generate a different name. */
dest_name = t_strdup_printf("%s-%04u", wanted_destname,
(uint32_t)random());
}
*dest_box_r = dest_box;
return 1;
}
static int
mailbox_move_all_mails(struct mailbox *src_box, const char *dest_name)
{
struct mailbox *dest_box;
struct mail_search_args *search_args;
struct mailbox_transaction_context *src_trans, *dest_trans;
struct mail_search_context *search_ctx;
struct mail_save_context *save_ctx;
struct mail *mail;
const char *errstr;
enum mail_error error;
int ret;
dest_box = mailbox_alloc(src_box->list, dest_name, 0);
if (mailbox_open(dest_box) < 0) {
errstr = mail_storage_get_last_error(dest_box->storage, &error);
i_error("lazy_expunge: Couldn't open DELETE dest mailbox "
"%s: %s", dest_name, errstr);
mailbox_free(&dest_box);
return -1;
}
src_trans = mailbox_transaction_begin(src_box, 0);
dest_trans = mailbox_transaction_begin(dest_box,
MAILBOX_TRANSACTION_FLAG_EXTERNAL);
search_args = mail_search_build_init();
mail_search_build_add_all(search_args);
search_ctx = mailbox_search_init(src_trans, search_args, NULL);
mail_search_args_unref(&search_args);
mail = mail_alloc(src_trans, 0, NULL);
while ((ret = mailbox_search_next(search_ctx, mail)) > 0) {
save_ctx = mailbox_save_alloc(dest_trans);
mailbox_save_copy_flags(save_ctx, mail);
if (mailbox_copy(&save_ctx, mail) < 0) {
if (!mail->expunged) {
ret = -1;
break;
}
}
}
mail_free(&mail);
if (mailbox_search_deinit(&search_ctx) < 0)
ret = -1;
(void)mailbox_transaction_commit(&src_trans);
if (ret == 0)
ret = mailbox_transaction_commit(&dest_trans);
else
mailbox_transaction_rollback(&dest_trans);
if (ret == 0)
ret = mailbox_delete(src_box);
mailbox_free(&dest_box);
return ret;
}
static int mailbox_mark_index_undeleted(struct mailbox *box)
{
struct mail_index_transaction *trans;
trans = mail_index_transaction_begin(box->view,
MAIL_INDEX_TRANSACTION_FLAG_EXTERNAL);
mail_index_set_undeleted(trans);
if (mail_index_transaction_commit(&trans) < 0) {
mail_storage_set_index_error(box);
return -1;
}
return 0;
}
static int lazy_expunge_mailbox_delete(struct mailbox *box)
{
union mailbox_module_context *lbox =
LAZY_EXPUNGE_CONTEXT(box);
struct lazy_expunge_mailbox_list *llist =
LAZY_EXPUNGE_LIST_CONTEXT(box->list);
struct mailbox_list *list = box->list;
struct mail_namespace *expunge_ns, *dest_ns;
struct mailbox *expunge_box;
const char *destname, *str;
enum mail_error error;
struct tm *tm;
char timestamp[256];
int ret;
if (llist->internal_namespace || !box->opened) {
/* a) deleting mailbox from lazy_expunge namespaces
b) deleting a \noselect mailbox */
return lbox->super.delete(box);
}
expunge_ns = get_lazy_ns(list->ns->user, LAZY_NAMESPACE_EXPUNGE);
dest_ns = get_lazy_ns(list->ns->user, LAZY_NAMESPACE_DELETE);
if (expunge_ns == dest_ns) {
/* if there are no expunged messages in this mailbox,
we can simply rename the mailbox to the destination name */
destname = box->name;
} else {
/* destination mailbox name needs to contain a timestamp */
tm = localtime(&ioloop_time);
if (strftime(timestamp, sizeof(timestamp),
"%Y%m%d-%H%M%S", tm) == 0) {
i_strocpy(timestamp, dec2str(ioloop_time),
sizeof(timestamp));
}
destname = t_strconcat(box->name, "-", timestamp, NULL);
}
/* avoid potential race conditions by marking it deleted */
if (mailbox_mark_index_deleted(box, TRUE) < 0)
return -1;
/* rename it into the lazy_expunge namespace */
ret = mailbox_move(box, dest_ns->list, destname, &expunge_box);
if (ret < 0)
return -1;
if (ret == 0) {
mail_storage_set_error(box->storage, MAIL_ERROR_NOTFOUND,
T_MAIL_ERR_MAILBOX_NOT_FOUND(box->name));
return -1;
}
/* other sessions now see the mailbox completely deleted.
since it's not really deleted in the lazy-expunge namespace,
we might want to change it again. so mark the index undeleted. */
if (mailbox_open(expunge_box) < 0) {
str = mail_storage_get_last_error(expunge_box->storage, &error);
i_error("lazy_expunge: Couldn't open DELETEd mailbox "
"%s: %s", expunge_box->name, str);
mailbox_free(&expunge_box);
return -1;
}
if (mailbox_mark_index_undeleted(expunge_box) < 0) {
mailbox_free(&expunge_box);
return -1;
}
if (expunge_ns == dest_ns && strcmp(expunge_box->name, box->name) != 0)
ret = mailbox_move_all_mails(expunge_box, box->name);
else
ret = 0;
mailbox_free(&expunge_box);
/* next move the expunged messages mailbox, if it exists */
dest_ns = get_lazy_ns(list->ns->user, LAZY_NAMESPACE_DELETE_EXPUNGE);
if (expunge_ns != dest_ns) {
struct mailbox *ret_box;
expunge_box = mailbox_alloc(expunge_ns->list, box->name, 0);
ret = mailbox_move(expunge_box, dest_ns->list,
destname, &ret_box);
if (ret > 0)
mailbox_free(&ret_box);
mailbox_free(&expunge_box);
}
return ret < 0 ? -1 : 0;
}
static int
lazy_expunge_mailbox_rename(struct mailbox *src, struct mailbox *dest,
bool rename_children)
{
union mailbox_module_context *lbox = LAZY_EXPUNGE_CONTEXT(src);
struct lazy_expunge_mailbox_list *src_llist =
LAZY_EXPUNGE_LIST_CONTEXT(src->list);
struct lazy_expunge_mailbox_list *dest_llist =
LAZY_EXPUNGE_LIST_CONTEXT(dest->list);
if (!src_llist->allow_rename &&
(src_llist->internal_namespace ||
dest_llist->internal_namespace)) {
mail_storage_set_error(src->storage, MAIL_ERROR_NOTPOSSIBLE,
"Can't rename mailboxes to/from expunge namespace.");
return -1;
}
return lbox->super.rename(src, dest, rename_children);
}
static void lazy_expunge_mailbox_allocated(struct mailbox *box)
{
struct lazy_expunge_mailbox_list *llist =
LAZY_EXPUNGE_LIST_CONTEXT(box->list);
union mailbox_module_context *mbox;
struct mailbox_vfuncs *v = box->vlast;
if (llist == NULL)
return;
mbox = p_new(box->pool, union mailbox_module_context, 1);
mbox->super = *v;
box->vlast = &mbox->super;
MODULE_CONTEXT_SET_SELF(box, lazy_expunge_mail_storage_module, mbox);
if (!llist->internal_namespace) {
v->transaction_begin = lazy_expunge_transaction_begin;
v->transaction_commit = lazy_expunge_transaction_commit;
v->transaction_rollback = lazy_expunge_transaction_rollback;
v->delete = lazy_expunge_mailbox_delete;
v->rename = lazy_expunge_mailbox_rename;
} else {
v->rename = lazy_expunge_mailbox_rename;
}
}
static void lazy_expunge_mail_namespace_storage_added(struct mail_namespace *ns)
{
struct mailbox_list *list = ns->list;
struct lazy_expunge_mail_user *luser =
LAZY_EXPUNGE_USER_CONTEXT(ns->user);
struct lazy_expunge_mailbox_list *llist;
const char *const *p;
unsigned int i;
if (luser == NULL)
return;
/* if this is one of our internal namespaces, mark it as such before
quota plugin sees it */
p = t_strsplit_spaces(luser->env, " ");
for (i = 0; i < LAZY_NAMESPACE_COUNT && *p != NULL; i++, p++) {
if (strcmp(ns->prefix, *p) == 0) {
ns->flags |= NAMESPACE_FLAG_NOQUOTA;
break;
}
}
if (luser != NULL && ns->type == NAMESPACE_PRIVATE) {
llist = p_new(list->pool, struct lazy_expunge_mailbox_list, 1);
MODULE_CONTEXT_SET(list, lazy_expunge_mailbox_list_module,
llist);
}
}
static void
lazy_expunge_mail_namespaces_created(struct mail_namespace *namespaces)
{
struct lazy_expunge_mail_user *luser =
LAZY_EXPUNGE_USER_CONTEXT(namespaces->user);
struct lazy_expunge_mailbox_list *llist;
const char *const *p;
int i;
if (luser == NULL)
return;
p = t_strsplit_spaces(luser->env, " ");
for (i = 0; i < LAZY_NAMESPACE_COUNT && *p != NULL; i++, p++) {
const char *name = *p;
luser->lazy_ns[i] =
mail_namespace_find_prefix(namespaces, name);
if (luser->lazy_ns[i] == NULL)
i_fatal("lazy_expunge: Unknown namespace: '%s'", name);
mail_namespace_ref(luser->lazy_ns[i]);
/* we don't want to override these namespaces' expunge/delete
operations. */
llist = LAZY_EXPUNGE_LIST_CONTEXT(luser->lazy_ns[i]->list);
llist->internal_namespace = TRUE;
}
if (i == 0)
i_fatal("lazy_expunge: No namespaces defined");
for (; i < LAZY_NAMESPACE_COUNT; i++) {
luser->lazy_ns[i] = luser->lazy_ns[i-1];
mail_namespace_ref(luser->lazy_ns[i]);
}
}
static void lazy_expunge_user_deinit(struct mail_user *user)
{
struct lazy_expunge_mail_user *luser = LAZY_EXPUNGE_USER_CONTEXT(user);
unsigned int i;
for (i = 0; i < LAZY_NAMESPACE_COUNT; i++)
mail_namespace_unref(&luser->lazy_ns[i]);
luser->module_ctx.super.deinit(user);
}
static void lazy_expunge_mail_user_created(struct mail_user *user)
{
struct mail_user_vfuncs *v = user->vlast;
struct lazy_expunge_mail_user *luser;
const char *env;
env = mail_user_plugin_getenv(user, "lazy_expunge");
if (env != NULL) {
luser = p_new(user->pool, struct lazy_expunge_mail_user, 1);
luser->module_ctx.super = *v;
user->vlast = &luser->module_ctx.super;
v->deinit = lazy_expunge_user_deinit;
luser->env = env;
MODULE_CONTEXT_SET(user, lazy_expunge_mail_user_module, luser);
} else if (user->mail_debug) {
i_debug("lazy_expunge: No lazy_expunge setting - "
"plugin disabled");
}
}
static struct mail_storage_hooks lazy_expunge_mail_storage_hooks = {
.mail_user_created = lazy_expunge_mail_user_created,
.mail_namespaces_created = lazy_expunge_mail_namespaces_created,
.mail_namespace_storage_added = lazy_expunge_mail_namespace_storage_added,
.mailbox_allocated = lazy_expunge_mailbox_allocated,
.mail_allocated = lazy_expunge_mail_allocated
};
void lazy_expunge_plugin_init(struct module *module)
{
mail_storage_hooks_add(module, &lazy_expunge_mail_storage_hooks);
}
void lazy_expunge_plugin_deinit(void)
{
mail_storage_hooks_remove(&lazy_expunge_mail_storage_hooks);
}