plugins/virtual/virtual-config.c

	virtual-config.c revision 391970ed208650d807191e5f2fc403f20f76ce18
/* Copyright (c) 2008-2016 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "array.h"
#include "crc32.h"
#include "istream.h"
#include "str.h"
#include "unichar.h"
#include "wildcard-match.h"
#include "imap-parser.h"
#include "imap-match.h"
#include "mail-namespace.h"
#include "mail-search-build.h"
#include "mail-search-parser.h"
#include "mailbox-attribute.h"
#include "mailbox-list-iter.h"
#include "imap-metadata.h"
#include "virtual-storage.h"
#include "virtual-plugin.h"

#include <unistd.h>
#include <fcntl.h>

struct virtual_parse_context {
    struct virtual_mailbox *mbox;
    struct istream *input;

    pool_t pool;
    string_t *rule;
    unsigned int rule_idx;

    char sep;
    bool have_wildcards;
    bool have_mailbox_defines;
};

static struct mail_search_args *
virtual_search_args_parse(const string_t *rule, const char **error_r)
{
    struct istream *input;
    struct imap_parser *imap_parser;
    const struct imap_arg *args;
    struct mail_search_parser *parser;
    struct mail_search_args *sargs;
    const char *charset = "UTF-8";
    int ret;

    if (str_len(rule) == 0) {
        sargs = mail_search_build_init();
        mail_search_build_add_all(sargs);
        return sargs;
    }

    input = i_stream_create_from_data(str_data(rule), str_len(rule));
    (void)i_stream_read(input);

    imap_parser = imap_parser_create(input, NULL, (size_t)-1);
    ret = imap_parser_finish_line(imap_parser, 0,  0, &args);
    if (ret < 0) {
        sargs = NULL;
        *error_r = t_strdup(imap_parser_get_error(imap_parser, NULL));
    } else {
        parser = mail_search_parser_init_imap(args);
        if (mail_search_build(mail_search_register_get_imap(),
                      parser, &charset, &sargs, error_r) < 0)
            sargs = NULL;
        mail_search_parser_deinit(&parser);
    }

    imap_parser_unref(&imap_parser);
    i_stream_destroy(&input);
    return sargs;
}

static int
virtual_config_add_rule(struct virtual_parse_context *ctx, const char **error_r)
{
    struct virtual_backend_box *const *bboxes;
    struct mail_search_args *search_args;
    unsigned int i, count;

    *error_r = NULL;

    if (ctx->rule_idx == array_count(&ctx->mbox->backend_boxes)) {
        i_assert(str_len(ctx->rule) == 0);
        return 0;
    }

    ctx->mbox->search_args_crc32 =
        crc32_str_more(ctx->mbox->search_args_crc32, str_c(ctx->rule));
    search_args = virtual_search_args_parse(ctx->rule, error_r);
    str_truncate(ctx->rule, 0);
    if (search_args == NULL) {
        i_assert(*error_r != NULL);
        *error_r = t_strconcat("Previous search rule is invalid: ",
                       *error_r, NULL);
        return -1;
    }

    /* update at all the mailboxes that were introduced since the previous
       rule. */
    bboxes = array_get(&ctx->mbox->backend_boxes, &count);
    i_assert(ctx->rule_idx < count);
    for (i = ctx->rule_idx; i < count; i++) {
        i_assert(bboxes[i]->search_args == NULL);
        mail_search_args_ref(search_args);
        bboxes[i]->search_args = search_args;
    }
    mail_search_args_unref(&search_args);

    ctx->rule_idx = array_count(&ctx->mbox->backend_boxes);
    return 0;
}

static int
virtual_config_parse_line(struct virtual_parse_context *ctx, const char *line,
              const char **error_r)
{
    struct mail_user *user = ctx->mbox->storage->storage.user;
    struct virtual_backend_box *bbox;
    const char *p;
    bool no_wildcards = FALSE;

    if (*line == ' ' || *line == '\t') {
        /* continues the previous search rule */
        if (ctx->rule_idx == array_count(&ctx->mbox->backend_boxes)) {
            *error_r = "Search rule without a mailbox";
            return -1;
        }
        while (*line == ' ' || *line == '\t') line++;
        str_append_c(ctx->rule, ' ');
        str_append(ctx->rule, line);
        return 0;
    }
    /* if there is no rule yet, it means we want the previous mailboxes
       to use the rule that comes later */
    if (str_len(ctx->rule) > 0) {
        if (virtual_config_add_rule(ctx, error_r) < 0)
            return -1;
    }
    if (!uni_utf8_str_is_valid(line)) {
        *error_r = t_strdup_printf("Mailbox name not UTF-8: %s",
                       line);
        return -1;
    }

    /* new mailbox. the search args are added to it later. */
    bbox = p_new(ctx->pool, struct virtual_backend_box, 1);
    bbox->virtual_mbox = ctx->mbox;
    if (strcasecmp(line, "INBOX") == 0)
        line = "INBOX";
    bbox->name = p_strdup(ctx->pool, line);
    switch (bbox->name[0]) {
    case '+':
        bbox->name++;
        bbox->clear_recent = TRUE;
        break;
    case '-':
        bbox->name++;
        bbox->negative_match = TRUE;
        break;
    case '!':
        /* save messages here */
        if (ctx->mbox->save_bbox != NULL) {
            *error_r = "Multiple save mailboxes defined";
            return -1;
        }
        bbox->name++;
        ctx->mbox->save_bbox = bbox;
        no_wildcards = TRUE;
        break;
    }
    if (bbox->name[0] == '/') {
        /* [+-!]/metadata entry:value */
        if ((p = strchr(bbox->name, ':')) == NULL) {
            *error_r = "':' separator missing between metadata entry name and value";
            return -1;
        }
        bbox->metadata_entry = p_strdup_until(ctx->pool, bbox->name, p++);
        bbox->metadata_value = p;
        if (!imap_metadata_verify_entry_name(bbox->metadata_entry, error_r))
            return -1;
        no_wildcards = TRUE;
    }

    if (!no_wildcards &&
        (strchr(bbox->name, '*') != NULL ||
         strchr(bbox->name, '%') != NULL)) {
        bbox->glob = imap_match_init(ctx->pool, bbox->name, TRUE, ctx->sep);
        ctx->have_wildcards = TRUE;
    }
    if (bbox->metadata_entry == NULL) {
        /* now that the prefix characters have been processed,
           find the namespace */
        bbox->ns = strcasecmp(bbox->name, "INBOX") == 0 ?
            mail_namespace_find_inbox(user->namespaces) :
            mail_namespace_find(user->namespaces, bbox->name);
        if (bbox->ns == NULL) {
            *error_r = t_strdup_printf("Namespace not found for %s",
                           bbox->name);
            return -1;
        }
        if (strcmp(bbox->name, ctx->mbox->box.vname) == 0) {
            *error_r = "Virtual mailbox can't point to itself";
            return -1;
        }
        ctx->have_mailbox_defines = TRUE;
    }

    array_append(&ctx->mbox->backend_boxes, &bbox, 1);
    return 0;
}

static void
virtual_mailbox_get_list_patterns(struct virtual_parse_context *ctx)
{
    struct virtual_mailbox *mbox = ctx->mbox;
    ARRAY_TYPE(mailbox_virtual_patterns) *dest;
    struct mailbox_virtual_pattern pattern;
    struct virtual_backend_box *const *bboxes;
    unsigned int i, count;

    memset(&pattern, 0, sizeof(pattern));
    bboxes = array_get_modifiable(&mbox->backend_boxes, &count);
    p_array_init(&mbox->list_include_patterns, ctx->pool, count);
    p_array_init(&mbox->list_exclude_patterns, ctx->pool, count);
    for (i = 0; i < count; i++) {
        if (bboxes[i]->metadata_entry == NULL)
            continue;
        pattern.ns = bboxes[i]->ns;
        pattern.pattern = bboxes[i]->name;
        if (bboxes[i]->negative_match)
            dest = &mbox->list_include_patterns;
        else {
            dest = &mbox->list_exclude_patterns;
            pattern.pattern++;
        }
        array_append(dest, &pattern, 1);
    }
}

static void
separate_wildcard_mailboxes(struct virtual_mailbox *mbox,
                ARRAY_TYPE(virtual_backend_box) *wildcard_boxes,
                ARRAY_TYPE(virtual_backend_box) *neg_boxes,
                ARRAY_TYPE(virtual_backend_box) *metadata_boxes)
{
    struct virtual_backend_box *const *bboxes;
    ARRAY_TYPE(virtual_backend_box) *dest;
    unsigned int i, count;

    bboxes = array_get_modifiable(&mbox->backend_boxes, &count);
    t_array_init(wildcard_boxes, I_MIN(16, count));
    t_array_init(neg_boxes, 4);
    t_array_init(metadata_boxes, 4);
    for (i = 0; i < count;) {
        if (bboxes[i]->metadata_entry != NULL)
            dest = metadata_boxes;
        else if (bboxes[i]->negative_match)
            dest = neg_boxes;
        else if (bboxes[i]->glob != NULL)
            dest = wildcard_boxes;
        else {
            dest = NULL;
            i++;
        }

        if (dest != NULL) {
            array_append(dest, &bboxes[i], 1);
            array_delete(&mbox->backend_boxes, i, 1);
            bboxes = array_get_modifiable(&mbox->backend_boxes,
                              &count);
        }
    }
}

static void virtual_config_copy_expanded(struct virtual_parse_context *ctx,
                     struct virtual_backend_box *wbox,
                     const char *name)
{
    struct virtual_backend_box *bbox;

    bbox = p_new(ctx->pool, struct virtual_backend_box, 1);
    *bbox = *wbox;
    bbox->name = p_strdup(ctx->pool, name);
    bbox->glob = NULL;
    bbox->wildcard = TRUE;
    mail_search_args_ref(bbox->search_args);
    array_append(&ctx->mbox->backend_boxes, &bbox, 1);
}

static bool virtual_ns_match(struct mail_namespace *config_ns,
                 struct mail_namespace *iter_ns)
{
    /* we match only one namespace for each pattern, except with shared
       namespaces match also autocreated children */
    if (config_ns == iter_ns)
        return TRUE;
    if (config_ns->type == iter_ns->type &&
        (config_ns->flags & NAMESPACE_FLAG_AUTOCREATED) == 0 &&
        (iter_ns->flags & NAMESPACE_FLAG_AUTOCREATED) != 0)
        return TRUE;
    if ((iter_ns->flags & NAMESPACE_FLAG_INBOX_USER) != 0 &&
        (config_ns->flags & NAMESPACE_FLAG_AUTOCREATED) != 0 &&
        config_ns->prefix_len == 0) {
        /* prefix="" namespace was autocreated, so e.g. "*" would match
           only that empty namespace. but we want "*" to also match
           the inbox=yes namespace, so check it here separately. */
        return TRUE;
    }
    return FALSE;
}

static bool virtual_config_match(const struct mailbox_info *info,
                 ARRAY_TYPE(virtual_backend_box) *boxes_arr,
                 unsigned int *idx_r)
{
    struct virtual_backend_box *const *boxes;
    unsigned int i, count;

    boxes = array_get_modifiable(boxes_arr, &count);
    for (i = 0; i < count; i++) {
        if (boxes[i]->glob != NULL) {
            if (virtual_ns_match(boxes[i]->ns, info->ns) &&
                imap_match(boxes[i]->glob,
                       info->vname) == IMAP_MATCH_YES) {
                *idx_r = i;
                return TRUE;
            }
        } else {
            if (strcmp(boxes[i]->name, info->vname) == 0) {
                *idx_r = i;
                return TRUE;
            }
        }
    }
    return FALSE;
}

static int virtual_config_box_metadata_match(struct mailbox *box,
                         struct virtual_backend_box *bbox,
                         const char **error_r)
{
    struct imap_metadata_transaction *imtrans;
    struct mail_attribute_value value;
    int ret;

    imtrans = imap_metadata_transaction_begin(box);
    ret = imap_metadata_get(imtrans, bbox->metadata_entry, &value);
    if (ret < 0)
        *error_r = t_strdup(imap_metadata_transaction_get_last_error(imtrans, NULL));
    if (ret > 0)
        ret = wildcard_match(value.value, bbox->metadata_value) ? 1 : 0;
    if (ret >= 0 && bbox->negative_match)
        ret = ret > 0 ? 0 : 1;
    (void)imap_metadata_transaction_commit(&imtrans, NULL, NULL);
    return ret;
}

static int
virtual_config_metadata_match(const struct mailbox_info *info,
                  ARRAY_TYPE(virtual_backend_box) *boxes_arr,
                  const char **error_r)
{
    struct virtual_backend_box *const *boxes;
    struct mailbox *box;
    unsigned int i, count;
    int ret = 1;

    boxes = array_get_modifiable(boxes_arr, &count);
    if (count == 0)
        return 1;

    box = mailbox_alloc(info->ns->list, info->vname, MAILBOX_FLAG_READONLY);
    for (i = 0; i < count; i++) {
        if ((ret = virtual_config_box_metadata_match(box, boxes[i], error_r)) <= 0)
            break;
    }
    mailbox_free(&box);
    return ret;
}

static int virtual_config_expand_wildcards(struct virtual_parse_context *ctx,
                       const char **error_r)
{
    const enum mail_namespace_type iter_ns_types =
        MAIL_NAMESPACE_TYPE_MASK_ALL;
    const enum mailbox_list_iter_flags iter_flags =
        MAILBOX_LIST_ITER_RETURN_NO_FLAGS;
    struct mail_user *user = ctx->mbox->storage->storage.user;
    ARRAY_TYPE(virtual_backend_box) wildcard_boxes, neg_boxes, metadata_boxes;
    struct mailbox_list_iterate_context *iter;
    struct virtual_backend_box *const *wboxes;
    const char **patterns;
    const struct mailbox_info *info;
    unsigned int i, j, count;
    int ret = 0;

    separate_wildcard_mailboxes(ctx->mbox, &wildcard_boxes,
                    &neg_boxes, &metadata_boxes);

    /* get patterns we want to list */
    wboxes = array_get_modifiable(&wildcard_boxes, &count);
    if (count == 0) {
        /* only negative wildcards - doesn't really make sense.
           just ignore. */
        return 0;
    }
    patterns = t_new(const char *, count + 1);
    for (i = 0; i < count; i++)
        patterns[i] = wboxes[i]->name;

    /* match listed mailboxes to wildcards */
    iter = mailbox_list_iter_init_namespaces(user->namespaces, patterns,
                         iter_ns_types, iter_flags);
    while ((info = mailbox_list_iter_next(iter)) != NULL) {
        /* skip non-selectable mailboxes (especially mbox
           directories) */
        if ((info->flags & MAILBOX_NOSELECT) != 0)
            continue;
        if (strcmp(info->vname, ctx->mbox->box.vname) == 0) {
            /* don't allow virtual folder to point to itself */
            continue;
        }

        if (virtual_config_match(info, &wildcard_boxes, &i) &&
            !virtual_config_match(info, &neg_boxes, &j) &&
            virtual_backend_box_lookup_name(ctx->mbox,
                            info->vname) == NULL) {
            ret = virtual_config_metadata_match(info, &metadata_boxes, error_r);
            if (ret < 0)
                break;
            if (ret > 0) {
                virtual_config_copy_expanded(ctx, wboxes[i],
                                 info->vname);
            }
        }
    }
    for (i = 0; i < count; i++)
        mail_search_args_unref(&wboxes[i]->search_args);
    if (mailbox_list_iter_deinit(&iter) < 0) {
        *error_r = mailbox_list_get_last_error(user->namespaces->list, NULL);
        return -1;
    }
    return ret < 0 ? -1 : 0;
}

static void virtual_config_search_args_dup(struct virtual_mailbox *mbox)
{
    struct virtual_backend_box *const *bboxes;
    struct mail_search_args *old_args;
    unsigned int i, count;

    bboxes = array_get_modifiable(&mbox->backend_boxes, &count);
    for (i = 0; i < count; i++) {
        old_args = bboxes[i]->search_args;
        bboxes[i]->search_args = mail_search_args_dup(old_args);
        mail_search_args_unref(&old_args);
    }
}

int virtual_config_read(struct virtual_mailbox *mbox)
{
    struct mail_storage *storage = mbox->box.storage;
    struct virtual_parse_context ctx;
    const char *box_path, *path, *line, *error;
    unsigned int linenum = 0;
    int fd, ret = 0;

    i_array_init(&mbox->backend_boxes, 8);
    mbox->search_args_crc32 = (uint32_t)-1;

    box_path = mailbox_get_path(&mbox->box);
    path = t_strconcat(box_path, "/"VIRTUAL_CONFIG_FNAME, NULL);
    fd = open(path, O_RDONLY);
    if (fd == -1) {
        if (errno == EACCES) {
            mail_storage_set_critical(storage, "%s",
                mail_error_eacces_msg("open", path));
        } else if (errno != ENOENT) {
            mail_storage_set_critical(storage,
                          "open(%s) failed: %m", path);
        } else if (errno == ENOENT) {
            mail_storage_set_error(storage, MAIL_ERROR_NOTFOUND,
                T_MAIL_ERR_MAILBOX_NOT_FOUND(mbox->box.vname));
        } else {
            mail_storage_set_critical(storage,
                "stat(%s) failed: %m", box_path);
        }
        return -1;
    }

    memset(&ctx, 0, sizeof(ctx));
    ctx.sep = mail_namespaces_get_root_sep(storage->user->namespaces);
    ctx.mbox = mbox;
    ctx.pool = mbox->box.pool;
    ctx.rule = t_str_new(256);
    ctx.input = i_stream_create_fd(fd, (size_t)-1);
    i_stream_set_return_partial_line(ctx.input, TRUE);
    while ((line = i_stream_read_next_line(ctx.input)) != NULL) {
        linenum++;
        if (*line == '#')
            continue;
        if (*line == '\0')
            ret = virtual_config_add_rule(&ctx, &error);
        else
            ret = virtual_config_parse_line(&ctx, line, &error);
        if (ret < 0) {
            mail_storage_set_critical(storage,
                          "%s: Error at line %u: %s",
                          path, linenum, error);
            break;
        }
    }
    if (ret == 0) {
        ret = virtual_config_add_rule(&ctx, &error);
        if (ret < 0) {
            mail_storage_set_critical(storage,
                          "%s: Error at line %u: %s",
                          path, linenum, error);
        }
    }

    virtual_mailbox_get_list_patterns(&ctx);
    if (ret == 0 && ctx.have_wildcards) {
        ret = virtual_config_expand_wildcards(&ctx, &error);
        if (ret < 0)
            mail_storage_set_critical(storage, "%s: %s", path, error);
    }

    if (ret == 0 && !ctx.have_mailbox_defines) {
        mail_storage_set_critical(storage,
                      "%s: No mailboxes defined", path);
        ret = -1;
    }
    if (ret == 0)
        virtual_config_search_args_dup(mbox);
    i_stream_unref(&ctx.input);
    i_close_fd(&fd);
    return ret;
}

void virtual_config_free(struct virtual_mailbox *mbox)
{
    struct virtual_backend_box *const *bboxes;
    unsigned int i, count;

    if (!array_is_created(&mbox->backend_boxes)) {
        /* mailbox wasn't opened */
        return;
    }

    bboxes = array_get_modifiable(&mbox->backend_boxes, &count);
    for (i = 0; i < count; i++) {
        if (bboxes[i]->search_args != NULL)
            mail_search_args_unref(&bboxes[i]->search_args);
    }
    array_free(&mbox->backend_boxes);
}