src/auth/passdb-cache.c

	passdb-cache.c revision 6ef7e31619edfaa17ed044b45861d106a86191ef
/* Copyright (C) 2004 Timo Sirainen */

#include "common.h"
#include "password-scheme.h"
#include "passdb.h"
#include "passdb-cache.h"

#include <stdlib.h>

struct auth_cache *passdb_cache = NULL;

static void list_save(struct auth_request *request, const char *const *list)
{
    const char *name, *value;

    if (*list == NULL)
        return;

    for (; *list != NULL; list++) {
        t_push();
        value = strchr(*list, '=');
        if (value == NULL) {
            name = *list;
            value = "";
        } else {
            name = t_strcut(*list, '=');
            value++;
        }

        auth_request_set_field(request, name, value, NULL);
        t_pop();
    }
}

bool passdb_cache_verify_plain(struct auth_request *request, const char *key,
                   const char *password,
                   enum passdb_result *result_r, int use_expired)
{
    const char *value, *cached_pw, *scheme, *const *list;
    int ret;
    bool expired;

    if (passdb_cache == NULL || key == NULL)
        return FALSE;

    /* value = password \t ... */
    value = auth_cache_lookup(passdb_cache, request, key, &expired);
    if (value == NULL || (expired && !use_expired))
        return FALSE;

    if (*value == '\0') {
        /* negative cache entry */
        auth_request_log_info(request, "cache", "User unknown");
        *result_r = PASSDB_RESULT_USER_UNKNOWN;
        return TRUE;
    }

    list = t_strsplit(value, "\t");
        list_save(request, list + 1);

    cached_pw = list[0];
    if (*cached_pw == '\0') {
        /* NULL password */
        auth_request_log_info(request, "cache", "NULL password access");
        *result_r = PASSDB_RESULT_OK;
        return TRUE;
    }

    scheme = password_get_scheme(&cached_pw);
    i_assert(scheme != NULL);

    ret = password_verify(password, cached_pw, scheme, request->user);
    if (ret < 0) {
        auth_request_log_error(request, "cache",
                       "Unknown password scheme %s", scheme);
    } else if (ret == 0) {
        auth_request_log_info(request, "cache", "Password mismatch");
    }

    *result_r = ret > 0 ? PASSDB_RESULT_OK :
        PASSDB_RESULT_PASSWORD_MISMATCH;
    return TRUE;
}

bool passdb_cache_lookup_credentials(struct auth_request *request,
                     const char *key, const char **password_r,
                     const char **scheme_r,
                     enum passdb_result *result_r,
                     bool use_expired)
{
    const char *value, *const *list;
    bool expired;

    if (passdb_cache == NULL)
        return FALSE;

    value = auth_cache_lookup(passdb_cache, request, key, &expired);
    if (value == NULL || (expired && !use_expired))
        return FALSE;

    if (*value == '\0') {
        /* negative cache entry */
        *result_r = PASSDB_RESULT_USER_UNKNOWN;
        *password_r = NULL;
        *scheme_r = NULL;
        return TRUE;
    }

    list = t_strsplit(value, "\t");
        list_save(request, list + 1);

    *result_r = PASSDB_RESULT_OK;
    *password_r = list[0];
    *scheme_r = password_get_scheme(password_r);
    i_assert(*scheme_r != NULL);
    return TRUE;
}

void passdb_cache_init(void)
{
    const char *env;
    size_t max_size;
    unsigned int cache_ttl;

    env = getenv("CACHE_SIZE");
    if (env == NULL)
        return;

    max_size = (size_t)strtoul(env, NULL, 10) * 1024;
    if (max_size == 0)
        return;

    env = getenv("CACHE_TTL");
    if (env == NULL)
        return;

    cache_ttl = (unsigned int)strtoul(env, NULL, 10);
    if (cache_ttl == 0)
        return;

    passdb_cache = auth_cache_new(max_size, cache_ttl);
}

void passdb_cache_deinit(void)
{
    if (passdb_cache != NULL)
        auth_cache_free(passdb_cache);
}