1 files changed, 407 insertions, 0 deletions

diff --git a/src/imap/cmd-copy.c b/src/imap/cmd-copy.c
new file mode 100644
index 0000000..1ce018b
--- /dev/null
+++ b/src/imap/cmd-copy.c
@@ -0,0 +1,407 @@
+/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */
+
+#include "imap-common.h"
+#include "str.h"
+#include "istream.h"
+#include "ostream.h"
+#include "imap-resp-code.h"
+#include "imap-util.h"
+#include "imap-commands.h"
+#include "imap-search-args.h"
+
+#include <time.h>
+
+#define COPY_CHECK_INTERVAL 100
+#define MOVE_COMMIT_INTERVAL 1000
+
+struct cmd_copy_context {
+	struct client_command_context *cmd;
+	struct mailbox *srcbox;
+	struct mailbox *destbox;
+	bool move;
+
+	unsigned int copy_count;
+
+	uint32_t uid_validity;
+	ARRAY_TYPE(seq_range) src_uids;
+	ARRAY_TYPE(seq_range) saved_uids;
+	bool hide_saved_uids;
+
+	const char *error_string;
+	enum mail_error mail_error;
+};
+
+static int client_send_sendalive_if_needed(struct client *client)
+{
+	time_t now, last_io;
+	int ret = 0;
+
+	if (o_stream_get_buffer_used_size(client->output) != 0)
+		return 0;
+
+	now = time(NULL);
+	last_io = I_MAX(client->last_input, client->last_output);
+	if (now - last_io > MAIL_STORAGE_STAYALIVE_SECS) {
+		o_stream_nsend_str(client->output, "* OK Hang in there..\r\n");
+		/* make sure it doesn't get stuck on the corked stream */
+		if (o_stream_uncork_flush(client->output) < 0)
+			ret = -1;
+		o_stream_cork(client->output);
+		client->last_output = now;
+	}
+	return ret;
+}
+
+static void copy_update_trashed(struct client *client, struct mailbox *box,
+				unsigned int count)
+{
+	const struct mailbox_settings *set;
+
+	set = mailbox_settings_find(mailbox_get_namespace(box),
+				    mailbox_get_vname(box));
+	if (set != NULL && set->special_use[0] != '\0' &&
+	    str_array_icase_find(t_strsplit_spaces(set->special_use, " "),
+				 "\\Trash"))
+		client->trashed_count += count;
+}
+
+static bool client_is_disconnected(struct client *client)
+{
+	if (client->fd_in == STDIN_FILENO) {
+		/* Skip this check for stdio clients. It's often used in
+		   testing where the test expects that all commands will be
+		   run even though stdin already has reached EOF. */
+		return FALSE;
+	}
+	ssize_t bytes = i_stream_read(client->input);
+	if (bytes == -1)
+		return TRUE;
+	if (bytes != 0)
+		i_stream_set_input_pending(client->input, TRUE);
+	return FALSE;
+}
+
+static int fetch_and_copy(struct cmd_copy_context *copy_ctx,
+			  const struct mail_search_args *uid_search_args)
+{
+	struct client *client = copy_ctx->cmd->client;
+	struct mailbox_transaction_context *t, *src_trans;
+	struct mail_search_args *search_args;
+	struct mail_search_context *search_ctx;
+	struct mail_save_context *save_ctx;
+	struct mail *mail;
+	const char *cmd_reason;
+	struct mail_transaction_commit_changes changes;
+	ARRAY_TYPE(seq_range) src_uids;
+	int ret;
+
+	/* convert uidset to seqset */
+	search_args = mail_search_args_dup(uid_search_args);
+	mail_search_args_init(search_args, copy_ctx->srcbox, TRUE, NULL);
+	/* make sure the number of messages didn't already change */
+	i_assert(uid_search_args->args->type == SEARCH_UIDSET);
+	i_assert(search_args->args->type == SEARCH_SEQSET ||
+		 (search_args->args->type == SEARCH_ALL &&
+		  search_args->args->match_not));
+	if (search_args->args->type != SEARCH_SEQSET ||
+	    seq_range_count(&search_args->args->value.seqset) !=
+	    seq_range_count(&uid_search_args->args->value.seqset)) {
+		mail_search_args_unref(&search_args);
+		return 0;
+	}
+
+	i_assert(o_stream_is_corked(client->output) ||
+		 client->output->stream_errno != 0);
+
+	cmd_reason = imap_client_command_get_reason(copy_ctx->cmd);
+	t = mailbox_transaction_begin(copy_ctx->destbox,
+				      MAILBOX_TRANSACTION_FLAG_EXTERNAL |
+				      MAILBOX_TRANSACTION_FLAG_ASSIGN_UIDS,
+				      cmd_reason);
+	/* Refresh source index so expunged mails will be noticed */
+	src_trans = mailbox_transaction_begin(copy_ctx->srcbox,
+					      MAILBOX_TRANSACTION_FLAG_REFRESH,
+					      cmd_reason);
+	search_ctx = mailbox_search_init(src_trans, search_args,
+					 NULL, 0, NULL);
+	mail_search_args_unref(&search_args);
+
+	t_array_init(&src_uids, 64);
+	ret = 1;
+	while (mailbox_search_next(search_ctx, &mail) && ret > 0) {
+		if (mail->expunged) {
+			ret = 0;
+			break;
+		}
+
+		if ((++copy_ctx->copy_count % COPY_CHECK_INTERVAL) == 0) {
+			/* If we're COPYing (not MOVEing), check if client has
+			   already disconnected. If yes, abort the COPY to
+			   avoid client duplicating the COPY again later.
+			   We can detect this as long as the client doesn't
+			   fill the input buffer full. */
+			if (client_send_sendalive_if_needed(client) < 0 ||
+			    (!copy_ctx->move &&
+			     client_is_disconnected(client))) {
+				/* Client disconnected. Use the same failure
+				   code path as if some messages were
+				   expunged. */
+				ret = 0;
+				break;
+			}
+		}
+
+		save_ctx = mailbox_save_alloc(t);
+		mailbox_save_copy_flags(save_ctx, mail);
+
+		if (copy_ctx->move) {
+			if (mailbox_move(&save_ctx, mail) < 0)
+				ret = -1;
+		} else {
+			if (mailbox_copy(&save_ctx, mail) < 0)
+				ret = -1;
+		}
+		if (ret < 0 && mail->expunged)
+			ret = 0;
+
+		if (ret > 0)
+			seq_range_array_add(&src_uids, mail->uid);
+	}
+
+	if (ret < 0) {
+		copy_ctx->error_string =
+			mailbox_get_last_error(copy_ctx->destbox, &copy_ctx->mail_error);
+	}
+	if (mailbox_search_deinit(&search_ctx) < 0 && ret >= 0) {
+		copy_ctx->error_string =
+			mailbox_get_last_error(copy_ctx->srcbox, &copy_ctx->mail_error);
+		ret = -1;
+	}
+
+	/* Do a final check before committing COPY to see if the client has
+	   already disconnected. */
+	if (!copy_ctx->move && client_is_disconnected(client))
+		ret = 0;
+
+	if (ret <= 0)
+		mailbox_transaction_rollback(&t);
+	else if (mailbox_transaction_commit_get_changes(&t, &changes) < 0) {
+		if (mailbox_get_last_mail_error(copy_ctx->destbox) == MAIL_ERROR_EXPUNGED) {
+			/* storage backend didn't notice the expunge until
+			   at commit time. */
+			ret = 0;
+		} else {
+			ret = -1;
+			copy_ctx->error_string =
+				mailbox_get_last_error(copy_ctx->destbox, &copy_ctx->mail_error);
+		}
+	} else {
+		if (changes.no_read_perm)
+			copy_ctx->hide_saved_uids = TRUE;
+
+		if (seq_range_count(&changes.saved_uids) == 0) {
+			/* storage doesn't support returning UIDs */
+			copy_ctx->hide_saved_uids = TRUE;
+		}
+
+		if (copy_ctx->uid_validity == 0)
+			copy_ctx->uid_validity = changes.uid_validity;
+		else if (copy_ctx->uid_validity != changes.uid_validity) {
+			/* UIDVALIDITY unexpectedly changed */
+			copy_ctx->hide_saved_uids = TRUE;
+		}
+		seq_range_array_merge(&copy_ctx->src_uids, &src_uids);
+		seq_range_array_merge(&copy_ctx->saved_uids, &changes.saved_uids);
+
+		i_assert(copy_ctx->copy_count == seq_range_count(&copy_ctx->saved_uids) ||
+			 copy_ctx->hide_saved_uids);
+		copy_update_trashed(client, copy_ctx->destbox, copy_ctx->copy_count);
+		pool_unref(&changes.pool);
+	}
+
+	if (!copy_ctx->move ||
+	    copy_ctx->srcbox == copy_ctx->destbox) {
+		/* copying or moving within the same mailbox
+		   succeeded or failed */
+		if (mailbox_transaction_commit(&src_trans) < 0 && ret >= 0) {
+			copy_ctx->error_string =
+				mailbox_get_last_error(copy_ctx->srcbox, &copy_ctx->mail_error);
+			ret = -1;
+		}
+	} else if (ret <= 0) {
+		/* move failed, don't expunge anything */
+		mailbox_transaction_rollback(&src_trans);
+	} else {
+		/* move succeeded */
+		if (mailbox_transaction_commit(&src_trans) < 0 ||
+		    mailbox_sync(copy_ctx->srcbox,
+				 MAILBOX_SYNC_FLAG_EXPUNGE) < 0) {
+			copy_ctx->error_string =
+				mailbox_get_last_error(copy_ctx->srcbox, &copy_ctx->mail_error);
+			ret = -1;
+		}
+	}
+	return ret;
+}
+
+static void cmd_move_send_untagged(struct cmd_copy_context *copy_ctx,
+				   string_t *msg, string_t *src_uidset)
+{
+	if (array_count(&copy_ctx->saved_uids) == 0)
+		return;
+	str_printfa(msg, "* OK [COPYUID %u %s ",
+		    copy_ctx->uid_validity, str_c(src_uidset));
+	imap_write_seq_range(msg, &copy_ctx->saved_uids);
+	str_append(msg, "] Moved UIDs.");
+	client_send_line(copy_ctx->cmd->client, str_c(msg));
+}
+
+static bool cmd_copy_full(struct client_command_context *cmd, bool move)
+{
+	struct client *client = cmd->client;
+	struct mailbox *destbox;
+        struct mail_search_args *search_args;
+	struct imap_search_seqset_iter *seqset_iter = NULL;
+	const char *messageset, *mailbox;
+	enum mailbox_sync_flags sync_flags = 0;
+	enum imap_sync_flags imap_flags = 0;
+	struct cmd_copy_context copy_ctx;
+	string_t *msg, *src_uidset;
+	int ret;
+
+	/* <message set> <mailbox> */
+	if (!client_read_string_args(cmd, 2, &messageset, &mailbox))
+		return FALSE;
+
+	if (!client_verify_open_mailbox(cmd))
+		return TRUE;
+
+	/* First convert the message set to sequences. This way nonexistent
+	   UIDs are dropped. */
+	ret = imap_search_get_seqset(cmd, messageset, cmd->uid, &search_args);
+	if (ret <= 0)
+		return ret < 0;
+	if (search_args->args->type == SEARCH_ALL) {
+		i_assert(search_args->args->match_not);
+		mail_search_args_unref(&search_args);
+		return cmd_sync(cmd, sync_flags, imap_flags,
+				"OK No messages found.");
+	}
+	/* Convert seqset to uidset. This is required for MOVE to work
+	   correctly, since it opens another view for the source mailbox
+	   that can have different sequences. */
+	imap_search_anyset_to_uidset(cmd, search_args);
+
+	if (client_open_save_dest_box(cmd, mailbox, &destbox) < 0) {
+		mail_search_args_unref(&search_args);
+		return TRUE;
+	}
+
+	i_zero(&copy_ctx);
+	copy_ctx.cmd = cmd;
+	copy_ctx.destbox = destbox;
+	if (destbox == client->mailbox || !move)
+		copy_ctx.srcbox = client->mailbox;
+	else {
+		copy_ctx.srcbox = mailbox_alloc(mailbox_get_namespace(client->mailbox)->list,
+						mailbox_get_vname(client->mailbox), 0);
+		if (mailbox_sync(copy_ctx.srcbox, 0) < 0) {
+			mail_search_args_unref(&search_args);
+			client_send_box_error(cmd, copy_ctx.srcbox);
+			mailbox_free(&copy_ctx.srcbox);
+			mailbox_free(&destbox);
+			return TRUE;
+		}
+	}
+	copy_ctx.move = move;
+	i_array_init(&copy_ctx.src_uids, 8);
+	i_array_init(&copy_ctx.saved_uids, 8);
+
+	if (move) {
+		/* When moving mails, perform the work in batches of
+		   MOVE_COMMIT_INTERVAL. Each such batch has its own
+		   transaction and search query. */
+		seqset_iter = imap_search_seqset_iter_init(search_args,
+			client->messages_count, MOVE_COMMIT_INTERVAL);
+	}
+	do {
+		T_BEGIN {
+			ret = fetch_and_copy(&copy_ctx, search_args);
+		} T_END;
+		if (ret <= 0) {
+			/* failed */
+			break;
+		}
+	} while (seqset_iter != NULL &&
+		 imap_search_seqset_iter_next(seqset_iter));
+	imap_search_seqset_iter_deinit(&seqset_iter);
+	mail_search_args_unref(&search_args);
+
+	src_uidset = t_str_new(256);
+	imap_write_seq_range(src_uidset, &copy_ctx.src_uids);
+
+	msg = t_str_new(256);
+	if (ret <= 0) {
+		if (move && array_count(&copy_ctx.src_uids) > 0) {
+			/* some of the messages were successfully moved */
+			cmd_move_send_untagged(&copy_ctx, msg, src_uidset);
+		}
+	} else if (copy_ctx.copy_count == 0) {
+		str_append(msg, "OK No messages found.");
+	} else if (seq_range_count(&copy_ctx.saved_uids) == 0 ||
+		   copy_ctx.hide_saved_uids) {
+		/* not supported by backend (virtual) or no read permissions
+		   for mailbox */
+		str_append(msg, move ? "OK Move completed." :
+			   "OK Copy completed.");
+	} else if (move) {
+		cmd_move_send_untagged(&copy_ctx, msg, src_uidset);
+		str_truncate(msg, 0);
+		str_append(msg, "OK Move completed.");
+	} else {
+		str_printfa(msg, "OK [COPYUID %u %s ", copy_ctx.uid_validity,
+			    str_c(src_uidset));
+		imap_write_seq_range(msg, &copy_ctx.saved_uids);
+		str_append(msg, "] Copy completed.");
+	}
+
+	array_free(&copy_ctx.src_uids);
+	array_free(&copy_ctx.saved_uids);
+
+	if (destbox != client->mailbox) {
+		if (move)
+			sync_flags |= MAILBOX_SYNC_FLAG_EXPUNGE;
+		else
+			sync_flags |= MAILBOX_SYNC_FLAG_FAST;
+		imap_flags |= IMAP_SYNC_FLAG_SAFE;
+		mailbox_free(&destbox);
+	} else if (move) {
+		sync_flags |= MAILBOX_SYNC_FLAG_EXPUNGE;
+		imap_flags |= IMAP_SYNC_FLAG_SAFE;
+	}
+	if (copy_ctx.srcbox != client->mailbox)
+		mailbox_free(&copy_ctx.srcbox);
+
+	if (ret > 0)
+		return cmd_sync(cmd, sync_flags, imap_flags, str_c(msg));
+	else if (ret == 0) {
+		/* some messages were expunged, sync them */
+		return cmd_sync(cmd, 0, 0,
+			"NO ["IMAP_RESP_CODE_EXPUNGEISSUED"] "
+			"Some of the requested messages no longer exist.");
+	} else {
+		client_send_error(cmd, copy_ctx.error_string,
+				  copy_ctx.mail_error);
+		return TRUE;
+	}
+}
+
+bool cmd_copy(struct client_command_context *cmd)
+{
+	return cmd_copy_full(cmd, FALSE);
+}
+
+bool cmd_move(struct client_command_context *cmd)
+{
+	return cmd_copy_full(cmd, TRUE);
+}