/*
* pg_krb5_authname -- returns a pointer to static space containing whatever
* name the user has authenticated to the system
*/
static const char *
pg_krb5_authname(char *PQerrormsg)
{
if (pg_krb5_init(PQerrormsg) != STATUS_OK)
return NULL;
return pg_krb5_name;
}
/*
* pg_krb5_authname -- returns a pointer to static space containing whatever
* name the user has authenticated to the system
*/
static const char *
pg_krb5_authname(char *PQerrormsg)
{
char *tmp_name;
struct krb5_info info;
info.pg_krb5_initialised = 0;
if (pg_krb5_init(PQerrormsg, &info) != STATUS_OK)
return NULL;
tmp_name = strdup(info.pg_krb5_name);
pg_krb5_destroy(&info);
return tmp_name;
}
/*
* pg_krb5_sendauth -- client routine to send authentication information to
* the server
*/
static int
pg_krb5_sendauth(PGconn *conn)
{
krb5_error_code retval;
int ret;
krb5_principal server;
krb5_auth_context auth_context = NULL;
krb5_error *err_ret = NULL;
struct krb5_info info;
info.pg_krb5_initialised = 0;
if (!(conn->pghost && conn->pghost[0] != '\0'))
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("host name must be specified\n"));
return STATUS_ERROR;
}
ret = pg_krb5_init(&conn->errorMessage, &info);
if (ret != STATUS_OK)
return ret;
retval = krb5_sname_to_principal(info.pg_krb5_context, conn->pghost,
conn->krbsrvname,
KRB5_NT_SRV_HST, &server);
if (retval)
{
printfPQExpBuffer(&conn->errorMessage,
"pg_krb5_sendauth: krb5_sname_to_principal: %s\n",
error_message(retval));
pg_krb5_destroy(&info);
return STATUS_ERROR;
}
/*
* libpq uses a non-blocking socket. But kerberos needs a blocking socket,
* and we have to block somehow to do mutual authentication anyway. So we
* temporarily make it blocking.
*/
if (!pg_set_block(conn->sock))
{
char sebuf[256];
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not set socket to blocking mode: %s\n"), pqStrerror(errno, sebuf, sizeof(sebuf)));
krb5_free_principal(info.pg_krb5_context, server);
pg_krb5_destroy(&info);
return STATUS_ERROR;
}
retval = krb5_sendauth(info.pg_krb5_context, &auth_context,
(krb5_pointer) & conn->sock, (char *) conn->krbsrvname,
info.pg_krb5_client, server,
AP_OPTS_MUTUAL_REQUIRED,
NULL, 0, /* no creds, use ccache instead */
info.pg_krb5_ccache, &err_ret, NULL, NULL);
if (retval)
{
if (retval == KRB5_SENDAUTH_REJECTED && err_ret)
{
#if defined(HAVE_KRB5_ERROR_TEXT_DATA)
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("Kerberos 5 authentication rejected: %*s\n"),
(int) err_ret->text.length, err_ret->text.data);
#elif defined(HAVE_KRB5_ERROR_E_DATA)
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("Kerberos 5 authentication rejected: %*s\n"),
(int) err_ret->e_data->length,
(const char *) err_ret->e_data->data);
#else
#error "bogus configuration"
#endif
}
else
{
printfPQExpBuffer(&conn->errorMessage,
"krb5_sendauth: %s\n", error_message(retval));
}
if (err_ret)
krb5_free_error(info.pg_krb5_context, err_ret);
ret = STATUS_ERROR;
}
krb5_free_principal(info.pg_krb5_context, server);
if (!pg_set_noblock(conn->sock))
{
char sebuf[256];
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not restore non-blocking mode on socket: %s\n"),
pqStrerror(errno, sebuf, sizeof(sebuf)));
ret = STATUS_ERROR;
}
pg_krb5_destroy(&info);
return ret;
}
/*
* pg_krb5_recvauth -- server routine to receive authentication information
* from the client
*
* We still need to compare the username obtained from the client's setup
* packet to the authenticated name, as described in pg_krb4_recvauth. This
* is a bit more problematic in v5, as described above in pg_an_to_ln.
*
* We have our own keytab file because postgres is unlikely to run as root,
* and so cannot read the default keytab.
*/
static int
pg_krb5_recvauth(Port *port)
{
krb5_error_code retval;
int ret;
krb5_auth_context auth_context = NULL;
krb5_ticket *ticket;
char *kusername;
ret = pg_krb5_init();
if (ret != STATUS_OK)
return ret;
retval = krb5_recvauth(pg_krb5_context, &auth_context,
(krb5_pointer) & port->sock, PG_KRB_SRVNAM,
pg_krb5_server, 0, pg_krb5_keytab, &ticket);
if (retval)
{
ereport(LOG,
(errmsg("Kerberos recvauth returned error %d",
retval)));
com_err("postgres", retval, "from krb5_recvauth");
return STATUS_ERROR;
}
/*
* The "client" structure comes out of the ticket and is therefore
* authenticated. Use it to check the username obtained from the
* postmaster startup packet.
*
* I have no idea why this is considered necessary.
*/
#if defined(HAVE_KRB5_TICKET_ENC_PART2)
retval = krb5_unparse_name(pg_krb5_context,
ticket->enc_part2->client, &kusername);
#elif defined(HAVE_KRB5_TICKET_CLIENT)
retval = krb5_unparse_name(pg_krb5_context,
ticket->client, &kusername);
#else
#error "bogus configuration"
#endif
if (retval)
{
ereport(LOG,
(errmsg("Kerberos unparse_name returned error %d",
retval)));
com_err("postgres", retval, "while unparsing client name");
krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
return STATUS_ERROR;
}
kusername = pg_an_to_ln(kusername);
if (strncmp(port->user_name, kusername, SM_DATABASE_USER))
{
ereport(LOG,
(errmsg("unexpected Kerberos user name received from client (received \"%s\", expected \"%s\")",
port->user_name, kusername)));
ret = STATUS_ERROR;
}
else
ret = STATUS_OK;
krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
free(kusername);
return ret;
}
/*
* pg_krb5_recvauth -- server routine to receive authentication information
* from the client
*
* We still need to compare the username obtained from the client's setup
* packet to the authenticated name.
*
* We have our own keytab file because postgres is unlikely to run as root,
* and so cannot read the default keytab.
*/
static int
pg_krb5_recvauth(Port *port)
{
krb5_error_code retval;
int ret;
krb5_auth_context auth_context = NULL;
krb5_ticket *ticket;
char *kusername;
char *cp;
if (get_role_line(port->user_name) == NULL)
return STATUS_ERROR;
ret = pg_krb5_init();
if (ret != STATUS_OK)
return ret;
retval = krb5_recvauth(pg_krb5_context, &auth_context,
(krb5_pointer) & port->sock, pg_krb_srvnam,
pg_krb5_server, 0, pg_krb5_keytab, &ticket);
if (retval)
{
ereport(LOG,
(errmsg("Kerberos recvauth returned error %d",
retval)));
com_err("postgres", retval, "from krb5_recvauth");
return STATUS_ERROR;
}
/*
* The "client" structure comes out of the ticket and is therefore
* authenticated. Use it to check the username obtained from the
* postmaster startup packet.
*/
#if defined(HAVE_KRB5_TICKET_ENC_PART2)
retval = krb5_unparse_name(pg_krb5_context,
ticket->enc_part2->client, &kusername);
#elif defined(HAVE_KRB5_TICKET_CLIENT)
retval = krb5_unparse_name(pg_krb5_context,
ticket->client, &kusername);
#else
#error "bogus configuration"
#endif
if (retval)
{
ereport(LOG,
(errmsg("Kerberos unparse_name returned error %d",
retval)));
com_err("postgres", retval, "while unparsing client name");
krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
return STATUS_ERROR;
}
cp = strchr(kusername, '@');
if (cp)
{
*cp = '\0';
cp++;
if (pg_krb_realm != NULL && strlen(pg_krb_realm))
{
/* Match realm against configured */
if (pg_krb_caseins_users)
ret = pg_strcasecmp(pg_krb_realm, cp);
else
ret = strcmp(pg_krb_realm, cp);
if (ret)
{
elog(DEBUG2,
"krb5 realm (%s) and configured realm (%s) don't match",
cp, pg_krb_realm);
krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
return STATUS_ERROR;
}
}
}
else if (pg_krb_realm && strlen(pg_krb_realm))
{
elog(DEBUG2,
"krb5 did not return realm but realm matching was requested");
krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
return STATUS_ERROR;
}
if (pg_krb_caseins_users)
ret = pg_strncasecmp(port->user_name, kusername, SM_DATABASE_USER);
else
ret = strncmp(port->user_name, kusername, SM_DATABASE_USER);
if (ret)
{
ereport(LOG,
(errmsg("unexpected Kerberos user name received from client (received \"%s\", expected \"%s\")",
port->user_name, kusername)));
ret = STATUS_ERROR;
}
else
ret = STATUS_OK;
krb5_free_ticket(pg_krb5_context, ticket);
krb5_auth_con_free(pg_krb5_context, auth_context);
free(kusername);
return ret;
}
/*
* pg_krb5_sendauth -- client routine to send authentication information to
* the server
*/
static int
pg_krb5_sendauth(char *PQerrormsg, int sock, const char *hostname)
{
krb5_error_code retval;
int ret;
krb5_principal server;
krb5_auth_context auth_context = NULL;
krb5_error *err_ret = NULL;
if (!hostname)
{
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
"pg_krb5_sendauth: hostname must be specified for Kerberos authentication\n");
return STATUS_ERROR;
}
ret = pg_krb5_init(PQerrormsg);
if (ret != STATUS_OK)
return ret;
retval = krb5_sname_to_principal(pg_krb5_context, hostname, PG_KRB_SRVNAM,
KRB5_NT_SRV_HST, &server);
if (retval)
{
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
"pg_krb5_sendauth: krb5_sname_to_principal: %s\n",
error_message(retval));
return STATUS_ERROR;
}
/*
* libpq uses a non-blocking socket. But kerberos needs a blocking
* socket, and we have to block somehow to do mutual authentication
* anyway. So we temporarily make it blocking.
*/
if (!pg_set_block(sock))
{
char sebuf[256];
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
libpq_gettext("could not set socket to blocking mode: %s\n"), pqStrerror(errno, sebuf, sizeof(sebuf)));
krb5_free_principal(pg_krb5_context, server);
return STATUS_ERROR;
}
retval = krb5_sendauth(pg_krb5_context, &auth_context,
(krb5_pointer) & sock, PG_KRB_SRVNAM,
pg_krb5_client, server,
AP_OPTS_MUTUAL_REQUIRED,
NULL, 0, /* no creds, use ccache instead */
pg_krb5_ccache, &err_ret, NULL, NULL);
if (retval)
{
if (retval == KRB5_SENDAUTH_REJECTED && err_ret)
{
#if defined(HAVE_KRB5_ERROR_TEXT_DATA)
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
libpq_gettext("Kerberos 5 authentication rejected: %*s\n"),
(int) err_ret->text.length, err_ret->text.data);
#elif defined(HAVE_KRB5_ERROR_E_DATA)
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
libpq_gettext("Kerberos 5 authentication rejected: %*s\n"),
(int) err_ret->e_data->length,
(const char *) err_ret->e_data->data);
#else
#error "bogus configuration"
#endif
}
else
{
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
"krb5_sendauth: %s\n", error_message(retval));
}
if (err_ret)
krb5_free_error(pg_krb5_context, err_ret);
ret = STATUS_ERROR;
}
krb5_free_principal(pg_krb5_context, server);
if (!pg_set_noblock(sock))
{
char sebuf[256];
snprintf(PQerrormsg, PQERRORMSG_LENGTH,
libpq_gettext("could not restore non-blocking mode on socket: %s\n"),
pqStrerror(errno, sebuf, sizeof(sebuf)));
ret = STATUS_ERROR;
}
return ret;
}
