src/auth/passdb.c

	passdb.c revision f3d506e525a720f214020ca0f989a1966b30edae
/* Copyright (c) 2002-2010 Dovecot authors, see the included COPYING file */

#include "auth-common.h"
#include "array.h"
#include "password-scheme.h"
#include "auth-worker-server.h"
#include "passdb.h"

#include <stdlib.h>

static ARRAY_DEFINE(passdb_interfaces, struct passdb_module_interface *);

static struct passdb_module_interface *passdb_interface_find(const char *name)
{
    struct passdb_module_interface *const *ifaces;

    array_foreach(&passdb_interfaces, ifaces) {
        struct passdb_module_interface *iface = *ifaces;

        if (strcmp(iface->name, name) == 0)
            return iface;
    }
    return NULL;
}

void passdb_register_module(struct passdb_module_interface *iface)
{
    struct passdb_module_interface *old_iface;

    old_iface = passdb_interface_find(iface->name);
    if (old_iface != NULL && old_iface->verify_plain == NULL) {
        /* replacing a "support not compiled in" passdb */
        passdb_unregister_module(old_iface);
    } else if (old_iface != NULL) {
        i_panic("passdb_register_module(%s): Already registered",
            iface->name);
    }
    array_append(&passdb_interfaces, &iface, 1);
}

void passdb_unregister_module(struct passdb_module_interface *iface)
{
    struct passdb_module_interface *const *ifaces;
    unsigned int idx;

    array_foreach(&passdb_interfaces, ifaces) {
        if (*ifaces == iface) {
            idx = array_foreach_idx(&passdb_interfaces, ifaces);
            array_delete(&passdb_interfaces, idx, 1);
            return;
        }
    }
    i_panic("passdb_unregister_module(%s): Not registered", iface->name);
}

bool passdb_get_credentials(struct auth_request *auth_request,
                const char *input, const char *input_scheme,
                const unsigned char **credentials_r, size_t *size_r)
{
    const char *wanted_scheme = auth_request->credentials_scheme;
    const char *plaintext, *username;
    int ret;

    if (auth_request->prefer_plain_credentials &&
        password_scheme_is_alias(input_scheme, "PLAIN")) {
        /* we've a plaintext scheme and we prefer to get it instead
           of converting it to the fallback scheme */
        wanted_scheme = "";
    }

    ret = password_decode(input, input_scheme, credentials_r, size_r);
    if (ret <= 0) {
        if (ret < 0) {
            auth_request_log_error(auth_request, "password",
                "Password in passdb is not in expected scheme %s",
                input_scheme);
        } else {
            auth_request_log_error(auth_request, "password",
                "Unknown scheme %s", input_scheme);
        }
        return FALSE;
    }

    if (*wanted_scheme == '\0') {
        /* anything goes. change the credentials_scheme to what we
           actually got, so blocking passdbs work. */
        auth_request->credentials_scheme =
            p_strdup(auth_request->pool, input_scheme);
        return TRUE;
    }

    if (!password_scheme_is_alias(input_scheme, wanted_scheme)) {
        if (!password_scheme_is_alias(input_scheme, "PLAIN")) {
            const char *error = t_strdup_printf(
                "Requested %s scheme, but we have only %s",
                wanted_scheme, input_scheme);
            if (auth_request->auth->set->debug_passwords) {
                error = t_strdup_printf("%s (input: %s)",
                            error, input);
            }
            auth_request_log_info(auth_request, "password",
                          "%s", error);
            return FALSE;
        }

        /* we can generate anything out of plaintext passwords */
        plaintext = t_strndup(*credentials_r, *size_r);
        username = auth_request->original_username;
        if (!auth_request->domain_is_realm &&
            strchr(username, '@') != NULL) {
            /* domain must not be used as realm. add the @realm. */
            username = t_strconcat(username, "@",
                           auth_request->realm, NULL);
        }
        if (auth_request->auth->set->debug_passwords) {
            auth_request_log_debug(auth_request, "password",
                "Generating %s from user '%s', password '%s'",
                wanted_scheme, username, plaintext);
        }
        if (!password_generate(plaintext, username,
                       wanted_scheme, credentials_r, size_r)) {
            auth_request_log_error(auth_request, "password",
                "Requested unknown scheme %s", wanted_scheme);
            return FALSE;
        }
    }

    return TRUE;
}

void passdb_handle_credentials(enum passdb_result result,
                   const char *password, const char *scheme,
                   lookup_credentials_callback_t *callback,
                               struct auth_request *auth_request)
{
    const unsigned char *credentials;
    size_t size = 0;

    if (result != PASSDB_RESULT_OK) {
        callback(result, NULL, 0, auth_request);
        return;
    }

    if (password == NULL) {
        auth_request_log_info(auth_request, "password",
            "Requested %s scheme, but we have a NULL password",
            auth_request->credentials_scheme);
        result = PASSDB_RESULT_SCHEME_NOT_AVAILABLE;
    } else if (!passdb_get_credentials(auth_request, password, scheme,
                       &credentials, &size)) {
        result = PASSDB_RESULT_SCHEME_NOT_AVAILABLE;
    }

    callback(result, credentials, size, auth_request);
}

struct passdb_module *
passdb_preinit(pool_t pool, const char *driver, const char *args)
{
    static unsigned int auth_passdb_id = 0;
    struct passdb_module_interface *iface;
    struct passdb_module *passdb;

    iface = passdb_interface_find(driver);
    if (iface == NULL)
        i_fatal("Unknown passdb driver '%s'", driver);
    if (iface->verify_plain == NULL) {
        i_fatal("Support not compiled in for passdb driver '%s'",
            driver);
    }

    if (iface->preinit == NULL && iface->init == NULL && *args != '\0')
        i_fatal("passdb %s: No args are supported: %s", driver, args);

    if (iface->preinit == NULL)
        passdb = p_new(pool, struct passdb_module, 1);
    else
        passdb = iface->preinit(pool, args);
    passdb->id = ++auth_passdb_id;
    passdb->iface = *iface;
    passdb->args = p_strdup(pool, args);
    return passdb;
}

void passdb_init(struct passdb_module *passdb)
{
    if (passdb->iface.init != NULL && !passdb->initialized) {
        passdb->initialized = TRUE;
        passdb->iface.init(passdb);
    }

    i_assert(passdb->default_pass_scheme != NULL ||
         passdb->cache_key == NULL);
}

void passdb_deinit(struct passdb_module *passdb)
{
    i_assert(passdb->initialized);

    if (passdb->iface.deinit != NULL)
        passdb->iface.deinit(passdb);
}

extern struct passdb_module_interface passdb_passwd;
extern struct passdb_module_interface passdb_bsdauth;
extern struct passdb_module_interface passdb_shadow;
extern struct passdb_module_interface passdb_passwd_file;
extern struct passdb_module_interface passdb_pam;
extern struct passdb_module_interface passdb_checkpassword;
extern struct passdb_module_interface passdb_vpopmail;
extern struct passdb_module_interface passdb_ldap;
extern struct passdb_module_interface passdb_sql;
extern struct passdb_module_interface passdb_sia;

void passdbs_init(void)
{
    i_array_init(&passdb_interfaces, 16);
    passdb_register_module(&passdb_passwd);
    passdb_register_module(&passdb_bsdauth);
    passdb_register_module(&passdb_passwd_file);
    passdb_register_module(&passdb_pam);
    passdb_register_module(&passdb_checkpassword);
    passdb_register_module(&passdb_shadow);
    passdb_register_module(&passdb_vpopmail);
    passdb_register_module(&passdb_ldap);
    passdb_register_module(&passdb_sql);
    passdb_register_module(&passdb_sia);
}

void passdbs_deinit(void)
{
    array_free(&passdb_interfaces);
}