src/imap/cmd-append.c

	cmd-append.c revision c96eb61168670cfdd7596baba18856d3f086a093
/* Copyright (c) 2002-2008 Dovecot authors, see the included COPYING file */

#include "common.h"
#include "ioloop.h"
#include "istream.h"
#include "ostream.h"
#include "str.h"
#include "commands.h"
#include "imap-parser.h"
#include "imap-date.h"
#include "mail-storage.h"

#include <sys/time.h>

struct cmd_append_context {
    struct client *client;
        struct client_command_context *cmd;
    struct mail_storage *storage;
    struct mailbox *box;
        struct mailbox_transaction_context *t;

    struct istream *input;
    uoff_t msg_size;

    struct imap_parser *save_parser;
    struct mail_save_context *save_ctx;
    unsigned int count;

    unsigned int message_input:1;
    unsigned int failed:1;
};

static void cmd_append_finish(struct cmd_append_context *ctx);
static bool cmd_append_continue_message(struct client_command_context *cmd);
static bool cmd_append_continue_parsing(struct client_command_context *cmd);

static void client_input_append(struct client_command_context *cmd)
{
    struct cmd_append_context *ctx = cmd->context;
    struct client *client = cmd->client;
    bool finished;

    i_assert(!client->destroyed);

    client->last_input = ioloop_time;
    timeout_reset(client->to_idle);

    switch (i_stream_read(client->input)) {
    case -1:
        /* disconnected */
        cmd_append_finish(cmd->context);
        /* Reset command so that client_destroy() doesn't try to call
           cmd_append_continue_message() anymore. */
        client_command_free(cmd);
        client_destroy(client, "Disconnected in APPEND");
        return;
    case -2:
        if (ctx->message_input) {
            /* message data, this is handled internally by
               mailbox_save_continue() */
            break;
        }
        cmd_append_finish(cmd->context);

        /* parameter word is longer than max. input buffer size.
           this is most likely an error, so skip the new data
           until newline is found. */
        client->input_skip_line = TRUE;

        client_send_command_error(cmd, "Too long argument.");
        cmd->param_error = TRUE;
        client_command_free(cmd);
        return;
    }

    o_stream_cork(client->output);
    finished = cmd->func(cmd);
    o_stream_uncork(client->output);
    if (!finished && cmd->state != CLIENT_COMMAND_STATE_DONE)
        (void)client_handle_unfinished_cmd(cmd);
    else
        client_command_free(cmd);
    if (cmd_sync_delayed(client))
        client_continue_pending_input(&client);
}

/* Returns -1 = error, 0 = need more data, 1 = successful. flags and
   internal_date may be NULL as a result, but mailbox and msg_size are always
   set when successful. */
static int validate_args(const struct imap_arg *args,
             const struct imap_arg **flags_r,
             const char **internal_date_r, uoff_t *msg_size_r,
             bool *nonsync_r)
{
    /* [<flags>] */
    if (args->type != IMAP_ARG_LIST)
        *flags_r = NULL;
    else {
        *flags_r = IMAP_ARG_LIST_ARGS(args);
        args++;
    }

    /* [<internal date>] */
    if (args->type != IMAP_ARG_STRING)
        *internal_date_r = NULL;
    else {
        *internal_date_r = IMAP_ARG_STR(args);
        args++;
    }

    if (args->type != IMAP_ARG_LITERAL_SIZE &&
        args->type != IMAP_ARG_LITERAL_SIZE_NONSYNC) {
        *nonsync_r = FALSE;
        return FALSE;
    }

    *nonsync_r = args->type == IMAP_ARG_LITERAL_SIZE_NONSYNC;
    *msg_size_r = IMAP_ARG_LITERAL_SIZE(args);
    return TRUE;
}

static void cmd_append_finish(struct cmd_append_context *ctx)
{
    imap_parser_destroy(&ctx->save_parser);

    i_assert(ctx->client->input_lock == ctx->cmd);

    io_remove(&ctx->client->io);
    /* we must put back the original flush callback before beginning to
       sync (the command is still unfinished at that point) */
    o_stream_set_flush_callback(ctx->client->output,
                    client_output, ctx->client);

    if (ctx->input != NULL)
        i_stream_unref(&ctx->input);
    if (ctx->save_ctx != NULL)
        mailbox_save_cancel(&ctx->save_ctx);
    if (ctx->t != NULL)
        mailbox_transaction_rollback(&ctx->t);
    if (ctx->box != ctx->cmd->client->mailbox && ctx->box != NULL)
        mailbox_close(&ctx->box);
}

static bool cmd_append_continue_cancel(struct client_command_context *cmd)
{
    struct cmd_append_context *ctx = cmd->context;
    size_t size;

    if (cmd->cancel) {
        cmd_append_finish(ctx);
        return TRUE;
    }

    (void)i_stream_read(ctx->input);
    (void)i_stream_get_data(ctx->input, &size);
    i_stream_skip(ctx->input, size);

    if (cmd->client->input->closed) {
        cmd_append_finish(ctx);
        return TRUE;
    }

    if (ctx->input->v_offset == ctx->msg_size) {
        /* finished, but with MULTIAPPEND and LITERAL+ we may get
           more messages. */
        i_stream_unref(&ctx->input);
        ctx->input = NULL;

        ctx->message_input = FALSE;
        imap_parser_reset(ctx->save_parser);
        cmd->func = cmd_append_continue_parsing;
        return cmd_append_continue_parsing(cmd);
    }

    return FALSE;
}

static bool cmd_append_cancel(struct cmd_append_context *ctx, bool nonsync)
{
    ctx->failed = TRUE;

    if (!nonsync) {
        cmd_append_finish(ctx);
        return TRUE;
    }

    /* we have to read the nonsynced literal so we don't treat the message
       data as commands. */
    ctx->input = i_stream_create_limit(ctx->client->input, ctx->msg_size);

    ctx->message_input = TRUE;
    ctx->cmd->func = cmd_append_continue_cancel;
    ctx->cmd->context = ctx;
    return cmd_append_continue_cancel(ctx->cmd);
}

static bool cmd_append_continue_parsing(struct client_command_context *cmd)
{
    struct client *client = cmd->client;
    struct cmd_append_context *ctx = cmd->context;
    const struct imap_arg *args;
    const struct imap_arg *flags_list;
    enum mail_flags flags;
    const char *const *keywords_list;
    struct mail_keywords *keywords;
    const char *internal_date_str;
    time_t internal_date;
    int ret, timezone_offset;
    bool nonsync;

    if (cmd->cancel) {
        cmd_append_finish(ctx);
        return TRUE;
    }

    /* if error occurs, the CRLF is already read. */
    client->input_skip_line = FALSE;

    /* [<flags>] [<internal date>] <message literal> */
    ret = imap_parser_read_args(ctx->save_parser, 0,
                    IMAP_PARSE_FLAG_LITERAL_SIZE, &args);
    if (ret == -1 || client->output->closed) {
        if (!ctx->failed)
            client_send_command_error(cmd, NULL);
        cmd_append_finish(ctx);
        return TRUE;
    }
    if (ret < 0) {
        /* need more data */
        return FALSE;
    }

    if (args->type == IMAP_ARG_EOL) {
        /* last message */
        enum mailbox_sync_flags sync_flags;
        enum imap_sync_flags imap_flags;
        uint32_t uid_validity, uid1, uid2;
        const char *msg;

        /* eat away the trailing CRLF */
        client->input_skip_line = TRUE;

        if (ctx->failed) {
            /* we failed earlier, error message is sent */
            cmd_append_finish(ctx);
            return TRUE;
        }

        ret = mailbox_transaction_commit_get_uids(&ctx->t,
                              &uid_validity,
                              &uid1, &uid2);
        if (ret < 0) {
            client_send_storage_error(cmd, ctx->storage);
            cmd_append_finish(ctx);
            return TRUE;
        }
        i_assert(ctx->count == uid2 - uid1 + 1);

        if (uid1 == uid2) {
            msg = t_strdup_printf("OK [APPENDUID %u %u] "
                          "Append completed.",
                          uid_validity, uid1);
        } else {
            msg = t_strdup_printf("OK [APPENDUID %u %u:%u] "
                          "Append completed.",
                          uid_validity, uid1, uid2);
        }

        if (ctx->box == cmd->client->mailbox) {
            sync_flags = 0;
            imap_flags = IMAP_SYNC_FLAG_SAFE;
        } else {
            sync_flags = MAILBOX_SYNC_FLAG_FAST;
            imap_flags = 0;
        }

        cmd_append_finish(ctx);
        return cmd_sync(cmd, sync_flags, imap_flags, msg);
    }

    if (!validate_args(args, &flags_list, &internal_date_str,
               &ctx->msg_size, &nonsync)) {
        client_send_command_error(cmd, "Invalid arguments.");
        return cmd_append_cancel(ctx, nonsync);
    }

    if (ctx->failed) {
        /* we failed earlier, make sure we just eat nonsync-literal
           if it's given. */
        return cmd_append_cancel(ctx, nonsync);
    }

    if (flags_list != NULL) {
        if (!client_parse_mail_flags(cmd, flags_list,
                         &flags, &keywords_list))
            return cmd_append_cancel(ctx, nonsync);
        if (keywords_list == NULL)
            keywords = NULL;
        else if (mailbox_keywords_create(ctx->box, keywords_list,
                         &keywords) < 0) {
            client_send_storage_error(cmd, ctx->storage);
            return cmd_append_cancel(ctx, nonsync);
        }
    } else {
        flags = 0;
        keywords = NULL;
    }

    if (internal_date_str == NULL) {
        /* no time given, default to now. */
        internal_date = (time_t)-1;
        timezone_offset = 0;
    } else if (!imap_parse_datetime(internal_date_str,
                    &internal_date, &timezone_offset)) {
        client_send_tagline(cmd, "BAD Invalid internal date.");
        return cmd_append_cancel(ctx, nonsync);
    }

    if (ctx->msg_size == 0) {
        /* no message data, abort */
        client_send_tagline(cmd, "NO Can't save a zero byte message.");
        return cmd_append_cancel(ctx, nonsync);
    }

    /* save the mail */
    ctx->input = i_stream_create_limit(client->input, ctx->msg_size);
    ret = mailbox_save_init(ctx->t, flags, keywords,
                internal_date, timezone_offset, NULL,
                ctx->input, FALSE, &ctx->save_ctx);

    if (keywords != NULL)
        mailbox_keywords_free(ctx->box, &keywords);

    if (ret < 0) {
        /* save initialization failed */
        client_send_storage_error(cmd, ctx->storage);
        return cmd_append_cancel(ctx, nonsync);
    }

    /* after literal comes CRLF, if we fail make sure we eat it away */
    client->input_skip_line = TRUE;

    if (!nonsync) {
        o_stream_send(client->output, "+ OK\r\n", 6);
        o_stream_flush(client->output);
        o_stream_uncork(client->output);
        o_stream_cork(client->output);
    }

    ctx->count++;
    ctx->message_input = TRUE;
    cmd->func = cmd_append_continue_message;
    return cmd_append_continue_message(cmd);
}

static bool cmd_append_continue_message(struct client_command_context *cmd)
{
    struct client *client = cmd->client;
    struct cmd_append_context *ctx = cmd->context;
    size_t size;
    int ret;

    if (cmd->cancel) {
        cmd_append_finish(ctx);
        return TRUE;
    }

    if (ctx->save_ctx != NULL) {
        while (ctx->input->v_offset != ctx->msg_size) {
            ret = i_stream_read(ctx->input);
            if (mailbox_save_continue(ctx->save_ctx) < 0) {
                /* we still have to finish reading the message
                   from client */
                mailbox_save_cancel(&ctx->save_ctx);
                break;
            }
            if (ret == -1 || ret == 0)
                break;
        }
    }

    if (ctx->save_ctx == NULL) {
        (void)i_stream_read(ctx->input);
        (void)i_stream_get_data(ctx->input, &size);
        i_stream_skip(ctx->input, size);
    }

    if (ctx->input->eof || client->input->closed) {
        bool all_written = ctx->input->v_offset == ctx->msg_size;

        /* finished */
        i_stream_unref(&ctx->input);
        ctx->input = NULL;

        if (ctx->save_ctx == NULL) {
            /* failed above */
            client_send_storage_error(cmd, ctx->storage);
            ctx->failed = TRUE;
        } else if (!all_written) {
            /* client disconnected before it finished sending the
               whole message. */
            ctx->failed = TRUE;
            mailbox_save_cancel(&ctx->save_ctx);
            client_disconnect(client, "EOF while appending");
        } else if (mailbox_save_finish(&ctx->save_ctx) < 0) {
            ctx->failed = TRUE;
            client_send_storage_error(cmd, ctx->storage);
        }
        ctx->save_ctx = NULL;

        if (client->input->closed) {
            cmd_append_finish(ctx);
            return TRUE;
        }

        /* prepare for next message */
        ctx->message_input = FALSE;
        imap_parser_reset(ctx->save_parser);
        cmd->func = cmd_append_continue_parsing;
        return cmd_append_continue_parsing(cmd);
    }

    return FALSE;
}

static struct mailbox *
get_mailbox(struct client_command_context *cmd, const char *name)
{
    struct mail_storage *storage;
    struct mailbox *box;

    if (!client_verify_mailbox_name(cmd, name, TRUE, FALSE))
        return NULL;

    storage = client_find_storage(cmd, &name);
    if (storage == NULL)
        return NULL;

    if (cmd->client->mailbox != NULL &&
        mailbox_equals(cmd->client->mailbox, storage, name))
        return cmd->client->mailbox;

    box = mailbox_open(storage, name, NULL, MAILBOX_OPEN_SAVEONLY |
               MAILBOX_OPEN_FAST | MAILBOX_OPEN_KEEP_RECENT);
    if (box == NULL) {
        client_send_storage_error(cmd, storage);
        return NULL;
    }
    return box;
}

bool cmd_append(struct client_command_context *cmd)
{
    struct client *client = cmd->client;
        struct cmd_append_context *ctx;
    const char *mailbox;

    if (client->syncing) {
        /* if transaction is created while its view is synced,
           appends aren't allowed for it. */
        cmd->state = CLIENT_COMMAND_STATE_WAIT_UNAMBIGUITY;
        return FALSE;
    }

    /* <mailbox> */
    if (!client_read_string_args(cmd, 1, &mailbox))
        return FALSE;

    /* we keep the input locked all the time */
    client->input_lock = cmd;

    ctx = p_new(cmd->pool, struct cmd_append_context, 1);
    ctx->cmd = cmd;
    ctx->client = client;
    ctx->box = get_mailbox(cmd, mailbox);
    if (ctx->box == NULL)
        ctx->failed = TRUE;
    else {
        ctx->storage = mailbox_get_storage(ctx->box);

        ctx->t = mailbox_transaction_begin(ctx->box,
                    MAILBOX_TRANSACTION_FLAG_EXTERNAL |
                    MAILBOX_TRANSACTION_FLAG_ASSIGN_UIDS);
    }

    io_remove(&client->io);
    client->io = io_add(i_stream_get_fd(client->input), IO_READ,
                client_input_append, cmd);
    /* append is special because we're only waiting on client input, not
       client output, so disable the standard output handler until we're
       finished */
    o_stream_unset_flush_callback(client->output);

    ctx->save_parser = imap_parser_create(client->input, client->output,
                          imap_max_line_length);

    cmd->func = cmd_append_continue_parsing;
    cmd->context = ctx;
    return cmd_append_continue_parsing(cmd);
}