vdb_lmdb.c

/*
 * Copyright (c) Regents of The University of Michigan
 * See COPYING.
 */

#include <config.h>

#include <dirent.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#include <sysexits.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>

#include "rabin.h"
#include "simvacation.h"
#include "vdb.h"

yastr lmdb_vdb_key(const yastr, const yastr);
void  lmdb_vdb_assert(MDB_env *, const char *);

VDB *
lmdb_vdb_init(const yastr rcpt) {
    int         rc;
    VDB *       vdb;
    const char *lmdb_path;

    if ((lmdb_path = ucl_object_tostring(
                 ucl_object_lookup_path(vac_config, "lmdb.path"))) == NULL) {
        syslog(LOG_ALERT, "lmdb vdb_init: no path configured");
        return NULL;
    }

    if ((vdb = calloc(1, sizeof(VDB))) == NULL) {
        return NULL;
    }

    if ((rc = mdb_env_create(&vdb->lmdb)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_init mdb_env_create: %s", mdb_strerror(rc));
        goto error;
    }

    if ((rc = mdb_env_set_assert(vdb->lmdb, &lmdb_vdb_assert)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_init mdb_env_set_assert: %s",
                mdb_strerror(rc));
        goto error;
    }

    if ((rc = mdb_env_set_mapsize(vdb->lmdb, 1073741824)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_init mdb_env_mapsize: %s",
                mdb_strerror(rc));
        goto error;
    }

    if ((rc = mdb_env_open(vdb->lmdb, lmdb_path, 0, 0664)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_init mdb_env_open: %s", mdb_strerror(rc));
        goto error;
    }

    vdb->rcpt = yasldup(rcpt);

    return vdb;

error:
    vdb_close(vdb);
    return NULL;
}

void
lmdb_vdb_assert(MDB_env *dbenv, const char *msg) {
    syslog(LOG_ALERT, "lmdb assert: %s", msg);
    exit(EX_TEMPFAIL);
}

void
lmdb_vdb_close(VDB *vdb) {
    if (vdb) {
        if (vdb->lmdb) {
            mdb_env_close(vdb->lmdb);
        }
        free(vdb);
    }
}

vdb_status
lmdb_vdb_recent(VDB *vdb, const yastr from, time_t interval) {
    int      rc, retval = VDB_STATUS_OK;
    time_t   last, now;
    MDB_txn *txn;
    MDB_dbi  dbi;
    MDB_val  key, data;
    yastr    keyval = NULL;

    if ((keyval = lmdb_vdb_key(vdb->rcpt, from)) == NULL) {
        return VDB_STATUS_OK;
    }

    if ((rc = mdb_txn_begin(vdb->lmdb, NULL, MDB_RDONLY, &txn)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_recent mdb_txn_begin: %s",
                mdb_strerror(rc));
        yaslfree(keyval);
        return VDB_STATUS_OK;
    }

    if ((rc = mdb_dbi_open(txn, NULL, MDB_CREATE, &dbi)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_recent mdb_dbi_open: %s", mdb_strerror(rc));
        goto cleanup;
    }

    key.mv_size = yasllen(keyval);
    key.mv_data = keyval;

    if ((rc = mdb_get(txn, dbi, &key, &data)) != 0) {
        if (rc != MDB_NOTFOUND) {
            syslog(LOG_ALERT, "lmdb vdb_recent mdb_get: %s", mdb_strerror(rc));
        }
        goto cleanup;
    }

    if (data.mv_size != sizeof(last)) {
        syslog(LOG_ALERT, "lmdb vdb_recent: retrieved bad data");
        goto cleanup;
    }

    last = *(time_t *)data.mv_data;

    if ((now = time(NULL)) < 0) {
        syslog(LOG_ALERT, "lmdb vdb_recent time: %m");
    } else if (now < (last + interval)) {
        retval = VDB_STATUS_RECENT;
    }

cleanup:
    yaslfree(keyval);
    mdb_txn_abort(txn);
    return (retval);
}

vac_result
lmdb_vdb_store_reply(VDB *vdb, const yastr from) {
    int      rc;
    time_t   now;
    MDB_txn *txn;
    MDB_dbi  dbi;
    MDB_val  key, data;
    char *   keyval;

    if ((now = time(NULL)) < 0) {
        syslog(LOG_ALERT, "lmdb vdb_store_reply time: %m");
        return VAC_RESULT_TEMPFAIL;
    }

    if ((rc = mdb_txn_begin(vdb->lmdb, NULL, 0, &txn)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_store_reply mdb_txn_begin: %s",
                mdb_strerror(rc));
        return VAC_RESULT_TEMPFAIL;
    }

    if ((rc = mdb_dbi_open(txn, NULL, MDB_CREATE, &dbi)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_store_reply mdb_dbi_open: %s",
                mdb_strerror(rc));
        mdb_txn_abort(txn);
        return VAC_RESULT_TEMPFAIL;
    }

    keyval = lmdb_vdb_key(vdb->rcpt, from);
    key.mv_size = strlen(keyval);
    key.mv_data = keyval;

    data.mv_size = sizeof(now);
    data.mv_data = &now;

    if ((rc = mdb_put(txn, dbi, &key, &data, 0)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_store_reply mdb_put: %s", mdb_strerror(rc));
        mdb_txn_abort(txn);
        return VAC_RESULT_TEMPFAIL;
    }

    if ((rc = mdb_txn_commit(txn)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_store_reply mdb_txn_commit: %s",
                mdb_strerror(rc));
        return VAC_RESULT_TEMPFAIL;
    }

    return VAC_RESULT_OK;
}

void
lmdb_vdb_gc(VDB *vdb) {
    int         rc;
    MDB_txn *   txn;
    MDB_dbi     dbi;
    MDB_cursor *cursor;
    MDB_val     key, data;
    time_t      expire;

    if ((expire = time(NULL)) < 0) {
        syslog(LOG_ALERT, "lmdb vdb_gc time: %m");
        return;
    }

    /* Clean up entries older than 7 days. */
    expire = expire - 604800;

    if ((rc = mdb_txn_begin(vdb->lmdb, NULL, 0, &txn)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_gc mdb_txn_begin: %s", mdb_strerror(rc));
        return;
    }

    if ((rc = mdb_dbi_open(txn, NULL, MDB_CREATE, &dbi)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_gc mdb_dbi_open: %s", mdb_strerror(rc));
        mdb_txn_abort(txn);
        return;
    }

    if ((rc = mdb_cursor_open(txn, dbi, &cursor)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_gc mdb_cursor_open: %s", mdb_strerror(rc));
        mdb_txn_abort(txn);
        return;
    }

    while ((rc = mdb_cursor_get(cursor, &key, &data, MDB_NEXT)) == 0) {
        if ((strncmp(key.mv_data, "user:", 5) == 0) &&
                data.mv_size == sizeof(expire) &&
                (time_t)data.mv_data < expire) {
            if ((rc = mdb_del(txn, dbi, &key, NULL)) != 0) {
                syslog(LOG_ALERT, "lmdb vdb_gc mdb_del: %s", mdb_strerror(rc));
            }
        }
    }
    if (rc != MDB_NOTFOUND) {
        syslog(LOG_ALERT, "lmdb vdb_gc mdb_cursor_get: %s", mdb_strerror(rc));
    }

    if ((rc = mdb_txn_commit(txn)) != 0) {
        syslog(LOG_ALERT, "lmdb vdb_gc mdb_txn_commit: %s", mdb_strerror(rc));
    }
}

yastr
lmdb_vdb_key(const yastr rcpt, const yastr from) {
    yastr ret = yaslauto("user:");
    ret = yaslcatprintf(
            ret, "%s:%lx", rcpt, (long)rabin_fingerprint(from, yasllen(from)));
    /* MDB_MAXKEYSIZE. 511 is the (old?) default and should be safe. */
    yaslrange(ret, 0, 511);

    syslog(LOG_DEBUG, "lmdb_vdb_key: %s", ret);

    return ret;
}