On 03/07/2016 11:40 AM, Cédric Le Goater wrote: > On 03/05/2016 12:41 PM, Corey Minyard wrote: >> On 03/02/2016 04:14 AM, Cédric Le Goater wrote: >>> Most IPMI command handlers in the BMC simulator start with a call to >>> the macro IPMI_CHECK_CMD_LEN() which verifies that a minimal number of >>> arguments expected by the command are indeed available. To achieve >>> this task, the macro implicitly uses local variables which is >>> misleading in the code. >>> >>> This patch adds a 'cmd_len_min' attribute to the struct IPMICmdHandler >>> defining the minimal number of arguments expected by the command and >>> moves this check in the global command handler ipmi_sim_handle_command(). >> >> This is much better. One style comment inline... >> >> Acked-by: Corey Minyard <cminy...@mvista.com> >> >>> Signed-off-by: Cédric Le Goater <c...@fr.ibm.com> >>> --- >>> hw/ipmi/ipmi_bmc_sim.c | 137 >>> ++++++++++++++++++++++--------------------------- >>> 1 file changed, 62 insertions(+), 75 deletions(-) >>> >>> diff --git a/hw/ipmi/ipmi_bmc_sim.c b/hw/ipmi/ipmi_bmc_sim.c >>> index 51d234aa1bf2..30b9fb48ea2d 100644 >>> --- a/hw/ipmi/ipmi_bmc_sim.c >>> +++ b/hw/ipmi/ipmi_bmc_sim.c >>> @@ -155,10 +155,15 @@ typedef struct IPMISensor { >>> typedef struct IPMIBmcSim IPMIBmcSim; >>> >>> #define MAX_NETFNS 64 >>> -typedef void (*IPMICmdHandler)(IPMIBmcSim *s, >>> - uint8_t *cmd, unsigned int cmd_len, >>> - uint8_t *rsp, unsigned int *rsp_len, >>> - unsigned int max_rsp_len); >>> + >>> +typedef struct IPMICmdHandler { >>> + void (*cmd_handler)(IPMIBmcSim *s, >>> + uint8_t *cmd, unsigned int cmd_len, >>> + uint8_t *rsp, unsigned int *rsp_len, >>> + unsigned int max_rsp_len); >>> + unsigned int cmd_len_min; >>> +} IPMICmdHandler; >>> + >>> typedef struct IPMINetfn { >>> unsigned int cmd_nums; >>> const IPMICmdHandler *cmd_handlers; >>> @@ -269,13 +274,6 @@ struct IPMIBmcSim { >>> rsp[(*rsp_len)++] = (b); \ >>> } while (0) >>> >>> -/* Verify that the received command is a certain length. */ >>> -#define IPMI_CHECK_CMD_LEN(l) \ >>> - if (cmd_len < l) { \ >>> - rsp[2] = IPMI_CC_REQUEST_DATA_LENGTH_INVALID; \ >>> - return; \ >>> - } >>> - >>> /* Check that the reservation in the command is valid. */ >>> #define IPMI_CHECK_RESERVATION(off, r) \ >>> do { \ >>> @@ -623,14 +621,19 @@ static void ipmi_sim_handle_command(IPMIBmc *b, >>> >>> /* Odd netfns are not valid, make sure the command is registered */ >>> if ((netfn & 1) || !ibs->netfns[netfn / 2] || >>> - (cmd[1] >= ibs->netfns[netfn / 2]->cmd_nums) || >>> - (!ibs->netfns[netfn / 2]->cmd_handlers[cmd[1]])) { >>> + (cmd[1] >= ibs->netfns[netfn / 2]->cmd_nums) || >>> + (!ibs->netfns[netfn / 2]->cmd_handlers[cmd[1]].cmd_handler)) { >>> rsp[2] = IPMI_CC_INVALID_CMD; >>> goto out; >> >> I'm not sure of the qemu style here, but the above change makes the code >> hard to read. > > Cleary. I was lazy. I will try to clarify what this code does with a helper > or some intermediate variables.
How's that ? @@ -591,6 +589,7 @@ static void ipmi_sim_handle_command(IPMI unsigned int rsp_len_holder = 0; unsigned int *rsp_len = &rsp_len_holder; unsigned int max_rsp_len = sizeof(rsp); + const IPMICmdHandler *hdl; /* Set up the response, set the low bit of NETFN. */ /* Note that max_rsp_len must be at least 3 */ @@ -623,14 +622,23 @@ static void ipmi_sim_handle_command(IPMI /* Odd netfns are not valid, make sure the command is registered */ if ((netfn & 1) || !ibs->netfns[netfn / 2] || - (cmd[1] >= ibs->netfns[netfn / 2]->cmd_nums) || - (!ibs->netfns[netfn / 2]->cmd_handlers[cmd[1]])) { + (cmd[1] >= ibs->netfns[netfn / 2]->cmd_nums)) { rsp[2] = IPMI_CC_INVALID_CMD; goto out; } - ibs->netfns[netfn / 2]->cmd_handlers[cmd[1]](ibs, cmd, cmd_len, rsp, rsp_len, - max_rsp_len); + hdl = &ibs->netfns[netfn / 2]->cmd_handlers[cmd[1]]; + if (!hdl->cmd_handler) { + rsp[2] = IPMI_CC_INVALID_CMD; + goto out; + } + + if (cmd_len < hdl->cmd_len_min) { + rsp[2] = IPMI_CC_REQUEST_DATA_LENGTH_INVALID; + goto out; + } + + hdl->cmd_handler(ibs, cmd, cmd_len, rsp, rsp_len, max_rsp_len); out: k->handle_rsp(s, msg_id, rsp, *rsp_len); The function still fits in one emacs page, so I think we are fine. Just waiting a bit for Marcel to chime in before sending a v3. Thanks, C. >> The qemu style really seems to be to not have big if statements like >> this, so maybe this crasy check should be moved to a separate function? >> >>> } >>> >>> - ibs->netfns[netfn / 2]->cmd_handlers[cmd[1]](ibs, cmd, cmd_len, rsp, >>> rsp_len, >>> - max_rsp_len); >>> + if (cmd_len < ibs->netfns[netfn / >>> 2]->cmd_handlers[cmd[1]].cmd_len_min) { >>> + rsp[2] = IPMI_CC_REQUEST_DATA_LENGTH_INVALID; >>> + goto out; >>> + } >>> + >>> + ibs->netfns[netfn / 2]->cmd_handlers[cmd[1]].cmd_handler(ibs, cmd, >>> cmd_len, >>> + rsp, rsp_len, max_rsp_len); >>> >>> out: >>> k->handle_rsp(s, msg_id, rsp, *rsp_len); >>> @@ -737,7 +740,6 @@ static void chassis_control(IPMIBmcSim *ibs, >>> IPMIInterface *s = ibs->parent.intf; >>> IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s); >>> >>> - IPMI_CHECK_CMD_LEN(3); >>> switch (cmd[2] & 0xf) { >>> case 0: /* power down */ >>> rsp[2] = k->do_hw_op(s, IPMI_POWEROFF_CHASSIS, 0); >>> @@ -838,7 +840,6 @@ static void set_acpi_power_state(IPMIBmcSim *ibs, >>> uint8_t *rsp, unsigned int *rsp_len, >>> unsigned int max_rsp_len) >>> { >>> - IPMI_CHECK_CMD_LEN(4); >>> ibs->acpi_power_state[0] = cmd[2]; >>> ibs->acpi_power_state[1] = cmd[3]; >>> } >>> @@ -869,7 +870,6 @@ static void set_bmc_global_enables(IPMIBmcSim *ibs, >>> uint8_t *rsp, unsigned int *rsp_len, >>> unsigned int max_rsp_len) >>> { >>> - IPMI_CHECK_CMD_LEN(3); >>> set_global_enables(ibs, cmd[2]); >>> } >>> >>> @@ -889,7 +889,6 @@ static void clr_msg_flags(IPMIBmcSim *ibs, >>> IPMIInterface *s = ibs->parent.intf; >>> IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s); >>> >>> - IPMI_CHECK_CMD_LEN(3); >>> ibs->msg_flags &= ~cmd[2]; >>> k->set_atn(s, attn_set(ibs), attn_irq_enabled(ibs)); >>> } >>> @@ -976,15 +975,17 @@ static void send_msg(IPMIBmcSim *ibs, >>> uint8_t *buf; >>> uint8_t netfn, rqLun, rsLun, rqSeq; >>> >>> - IPMI_CHECK_CMD_LEN(3); >>> - >>> if (cmd[2] != 0) { >>> /* We only handle channel 0 with no options */ >>> rsp[2] = IPMI_CC_INVALID_DATA_FIELD; >>> return; >>> } >>> >>> - IPMI_CHECK_CMD_LEN(10); >>> + if (cmd_len < 10) { >>> + rsp[2] = IPMI_CC_REQUEST_DATA_LENGTH_INVALID; >>> + return; >>> + } >>> + >>> if (cmd[3] != 0x40) { >>> /* We only emulate a MC at address 0x40. */ >>> rsp[2] = 0x83; /* NAK on write */ >>> @@ -1092,7 +1093,6 @@ static void set_watchdog_timer(IPMIBmcSim *ibs, >>> IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s); >>> unsigned int val; >>> >>> - IPMI_CHECK_CMD_LEN(8); >>> val = cmd[2] & 0x7; /* Validate use */ >>> if (val == 0 || val > 5) { >>> rsp[2] = IPMI_CC_INVALID_DATA_FIELD; >>> @@ -1217,7 +1217,6 @@ static void get_sdr(IPMIBmcSim *ibs, >>> uint16_t nextrec; >>> struct ipmi_sdr_header *sdrh; >>> >>> - IPMI_CHECK_CMD_LEN(8); >>> if (cmd[6]) { >>> IPMI_CHECK_RESERVATION(2, ibs->sdr.reservation); >>> } >>> @@ -1271,7 +1270,6 @@ static void clear_sdr_rep(IPMIBmcSim *ibs, >>> uint8_t *rsp, unsigned int *rsp_len, >>> unsigned int max_rsp_len) >>> { >>> - IPMI_CHECK_CMD_LEN(8); >>> IPMI_CHECK_RESERVATION(2, ibs->sdr.reservation); >>> if (cmd[4] != 'C' || cmd[5] != 'L' || cmd[6] != 'R') { >>> rsp[2] = IPMI_CC_INVALID_DATA_FIELD; >>> @@ -1330,7 +1328,6 @@ static void get_sel_entry(IPMIBmcSim *ibs, >>> { >>> unsigned int val; >>> >>> - IPMI_CHECK_CMD_LEN(8); >>> if (cmd[6]) { >>> IPMI_CHECK_RESERVATION(2, ibs->sel.reservation); >>> } >>> @@ -1375,7 +1372,6 @@ static void add_sel_entry(IPMIBmcSim *ibs, >>> uint8_t *rsp, unsigned int *rsp_len, >>> unsigned int max_rsp_len) >>> { >>> - IPMI_CHECK_CMD_LEN(18); >>> if (sel_add_event(ibs, cmd + 2)) { >>> rsp[2] = IPMI_CC_OUT_OF_SPACE; >>> return; >>> @@ -1390,7 +1386,6 @@ static void clear_sel(IPMIBmcSim *ibs, >>> uint8_t *rsp, unsigned int *rsp_len, >>> unsigned int max_rsp_len) >>> { >>> - IPMI_CHECK_CMD_LEN(8); >>> IPMI_CHECK_RESERVATION(2, ibs->sel.reservation); >>> if (cmd[4] != 'C' || cmd[5] != 'L' || cmd[6] != 'R') { >>> rsp[2] = IPMI_CC_INVALID_DATA_FIELD; >>> @@ -1434,7 +1429,6 @@ static void set_sel_time(IPMIBmcSim *ibs, >>> uint32_t val; >>> struct ipmi_time now; >>> >>> - IPMI_CHECK_CMD_LEN(6); >>> val = cmd[2] | (cmd[3] << 8) | (cmd[4] << 16) | (cmd[5] << 24); >>> ipmi_gettime(&now); >>> ibs->sel.time_offset = now.tv_sec - ((long) val); >>> @@ -1447,7 +1441,6 @@ static void set_sensor_evt_enable(IPMIBmcSim *ibs, >>> { >>> IPMISensor *sens; >>> >>> - IPMI_CHECK_CMD_LEN(4); >>> if ((cmd[2] >= MAX_SENSORS) || >>> !IPMI_SENSOR_GET_PRESENT(ibs->sensors + cmd[2])) { >>> rsp[2] = IPMI_CC_REQ_ENTRY_NOT_PRESENT; >>> @@ -1499,7 +1492,6 @@ static void get_sensor_evt_enable(IPMIBmcSim *ibs, >>> { >>> IPMISensor *sens; >>> >>> - IPMI_CHECK_CMD_LEN(3); >>> if ((cmd[2] >= MAX_SENSORS) || >>> !IPMI_SENSOR_GET_PRESENT(ibs->sensors + cmd[2])) { >>> rsp[2] = IPMI_CC_REQ_ENTRY_NOT_PRESENT; >>> @@ -1520,7 +1512,6 @@ static void rearm_sensor_evts(IPMIBmcSim *ibs, >>> { >>> IPMISensor *sens; >>> >>> - IPMI_CHECK_CMD_LEN(4); >>> if ((cmd[2] >= MAX_SENSORS) || >>> !IPMI_SENSOR_GET_PRESENT(ibs->sensors + cmd[2])) { >>> rsp[2] = IPMI_CC_REQ_ENTRY_NOT_PRESENT; >>> @@ -1542,7 +1533,6 @@ static void get_sensor_evt_status(IPMIBmcSim *ibs, >>> { >>> IPMISensor *sens; >>> >>> - IPMI_CHECK_CMD_LEN(3); >>> if ((cmd[2] >= MAX_SENSORS) || >>> !IPMI_SENSOR_GET_PRESENT(ibs->sensors + cmd[2])) { >>> rsp[2] = IPMI_CC_REQ_ENTRY_NOT_PRESENT; >>> @@ -1564,7 +1554,6 @@ static void get_sensor_reading(IPMIBmcSim *ibs, >>> { >>> IPMISensor *sens; >>> >>> - IPMI_CHECK_CMD_LEN(3); >>> if ((cmd[2] >= MAX_SENSORS) || >>> !IPMI_SENSOR_GET_PRESENT(ibs->sensors + cmd[2])) { >>> rsp[2] = IPMI_CC_REQ_ENTRY_NOT_PRESENT; >>> @@ -1587,7 +1576,6 @@ static void set_sensor_type(IPMIBmcSim *ibs, >>> IPMISensor *sens; >>> >>> >>> - IPMI_CHECK_CMD_LEN(5); >>> if ((cmd[2] >= MAX_SENSORS) || >>> !IPMI_SENSOR_GET_PRESENT(ibs->sensors + cmd[2])) { >>> rsp[2] = IPMI_CC_REQ_ENTRY_NOT_PRESENT; >>> @@ -1606,7 +1594,6 @@ static void get_sensor_type(IPMIBmcSim *ibs, >>> IPMISensor *sens; >>> >>> >>> - IPMI_CHECK_CMD_LEN(3); >>> if ((cmd[2] >= MAX_SENSORS) || >>> !IPMI_SENSOR_GET_PRESENT(ibs->sensors + cmd[2])) { >>> rsp[2] = IPMI_CC_REQ_ENTRY_NOT_PRESENT; >>> @@ -1619,10 +1606,10 @@ static void get_sensor_type(IPMIBmcSim *ibs, >>> >>> >>> static const IPMICmdHandler chassis_cmds[] = { >>> - [IPMI_CMD_GET_CHASSIS_CAPABILITIES] = chassis_capabilities, >>> - [IPMI_CMD_GET_CHASSIS_STATUS] = chassis_status, >>> - [IPMI_CMD_CHASSIS_CONTROL] = chassis_control, >>> - [IPMI_CMD_GET_SYS_RESTART_CAUSE] = chassis_get_sys_restart_cause >>> + [IPMI_CMD_GET_CHASSIS_CAPABILITIES] = { chassis_capabilities }, >>> + [IPMI_CMD_GET_CHASSIS_STATUS] = { chassis_status }, >>> + [IPMI_CMD_CHASSIS_CONTROL] = { chassis_control, 3 }, >>> + [IPMI_CMD_GET_SYS_RESTART_CAUSE] = { chassis_get_sys_restart_cause } >>> }; >>> static const IPMINetfn chassis_netfn = { >>> .cmd_nums = ARRAY_SIZE(chassis_cmds), >>> @@ -1630,13 +1617,13 @@ static const IPMINetfn chassis_netfn = { >>> }; >>> >>> static const IPMICmdHandler sensor_event_cmds[] = { >>> - [IPMI_CMD_SET_SENSOR_EVT_ENABLE] = set_sensor_evt_enable, >>> - [IPMI_CMD_GET_SENSOR_EVT_ENABLE] = get_sensor_evt_enable, >>> - [IPMI_CMD_REARM_SENSOR_EVTS] = rearm_sensor_evts, >>> - [IPMI_CMD_GET_SENSOR_EVT_STATUS] = get_sensor_evt_status, >>> - [IPMI_CMD_GET_SENSOR_READING] = get_sensor_reading, >>> - [IPMI_CMD_SET_SENSOR_TYPE] = set_sensor_type, >>> - [IPMI_CMD_GET_SENSOR_TYPE] = get_sensor_type, >>> + [IPMI_CMD_SET_SENSOR_EVT_ENABLE] = { set_sensor_evt_enable, 4 }, >>> + [IPMI_CMD_GET_SENSOR_EVT_ENABLE] = { get_sensor_evt_enable, 3 }, >>> + [IPMI_CMD_REARM_SENSOR_EVTS] = { rearm_sensor_evts, 4 }, >>> + [IPMI_CMD_GET_SENSOR_EVT_STATUS] = { get_sensor_evt_status, 3 }, >>> + [IPMI_CMD_GET_SENSOR_READING] = { get_sensor_reading, 3 }, >>> + [IPMI_CMD_SET_SENSOR_TYPE] = { set_sensor_type, 5 }, >>> + [IPMI_CMD_GET_SENSOR_TYPE] = { get_sensor_type, 3 }, >>> }; >>> static const IPMINetfn sensor_event_netfn = { >>> .cmd_nums = ARRAY_SIZE(sensor_event_cmds), >>> @@ -1644,22 +1631,22 @@ static const IPMINetfn sensor_event_netfn = { >>> }; >>> >>> static const IPMICmdHandler app_cmds[] = { >>> - [IPMI_CMD_GET_DEVICE_ID] = get_device_id, >>> - [IPMI_CMD_COLD_RESET] = cold_reset, >>> - [IPMI_CMD_WARM_RESET] = warm_reset, >>> - [IPMI_CMD_SET_ACPI_POWER_STATE] = set_acpi_power_state, >>> - [IPMI_CMD_GET_ACPI_POWER_STATE] = get_acpi_power_state, >>> - [IPMI_CMD_GET_DEVICE_GUID] = get_device_guid, >>> - [IPMI_CMD_SET_BMC_GLOBAL_ENABLES] = set_bmc_global_enables, >>> - [IPMI_CMD_GET_BMC_GLOBAL_ENABLES] = get_bmc_global_enables, >>> - [IPMI_CMD_CLR_MSG_FLAGS] = clr_msg_flags, >>> - [IPMI_CMD_GET_MSG_FLAGS] = get_msg_flags, >>> - [IPMI_CMD_GET_MSG] = get_msg, >>> - [IPMI_CMD_SEND_MSG] = send_msg, >>> - [IPMI_CMD_READ_EVT_MSG_BUF] = read_evt_msg_buf, >>> - [IPMI_CMD_RESET_WATCHDOG_TIMER] = reset_watchdog_timer, >>> - [IPMI_CMD_SET_WATCHDOG_TIMER] = set_watchdog_timer, >>> - [IPMI_CMD_GET_WATCHDOG_TIMER] = get_watchdog_timer, >>> + [IPMI_CMD_GET_DEVICE_ID] = { get_device_id }, >>> + [IPMI_CMD_COLD_RESET] = { cold_reset }, >>> + [IPMI_CMD_WARM_RESET] = { warm_reset }, >>> + [IPMI_CMD_SET_ACPI_POWER_STATE] = { set_acpi_power_state, 4 }, >>> + [IPMI_CMD_GET_ACPI_POWER_STATE] = { get_acpi_power_state }, >>> + [IPMI_CMD_GET_DEVICE_GUID] = { get_device_guid }, >>> + [IPMI_CMD_SET_BMC_GLOBAL_ENABLES] = { set_bmc_global_enables, 3 }, >>> + [IPMI_CMD_GET_BMC_GLOBAL_ENABLES] = { get_bmc_global_enables }, >>> + [IPMI_CMD_CLR_MSG_FLAGS] = { clr_msg_flags, 3 }, >>> + [IPMI_CMD_GET_MSG_FLAGS] = { get_msg_flags }, >>> + [IPMI_CMD_GET_MSG] = { get_msg }, >>> + [IPMI_CMD_SEND_MSG] = { send_msg, 3 }, >>> + [IPMI_CMD_READ_EVT_MSG_BUF] = { read_evt_msg_buf }, >>> + [IPMI_CMD_RESET_WATCHDOG_TIMER] = { reset_watchdog_timer }, >>> + [IPMI_CMD_SET_WATCHDOG_TIMER] = { set_watchdog_timer, 8 }, >>> + [IPMI_CMD_GET_WATCHDOG_TIMER] = { get_watchdog_timer }, >>> }; >>> static const IPMINetfn app_netfn = { >>> .cmd_nums = ARRAY_SIZE(app_cmds), >>> @@ -1667,18 +1654,18 @@ static const IPMINetfn app_netfn = { >>> }; >>> >>> static const IPMICmdHandler storage_cmds[] = { >>> - [IPMI_CMD_GET_SDR_REP_INFO] = get_sdr_rep_info, >>> - [IPMI_CMD_RESERVE_SDR_REP] = reserve_sdr_rep, >>> - [IPMI_CMD_GET_SDR] = get_sdr, >>> - [IPMI_CMD_ADD_SDR] = add_sdr, >>> - [IPMI_CMD_CLEAR_SDR_REP] = clear_sdr_rep, >>> - [IPMI_CMD_GET_SEL_INFO] = get_sel_info, >>> - [IPMI_CMD_RESERVE_SEL] = reserve_sel, >>> - [IPMI_CMD_GET_SEL_ENTRY] = get_sel_entry, >>> - [IPMI_CMD_ADD_SEL_ENTRY] = add_sel_entry, >>> - [IPMI_CMD_CLEAR_SEL] = clear_sel, >>> - [IPMI_CMD_GET_SEL_TIME] = get_sel_time, >>> - [IPMI_CMD_SET_SEL_TIME] = set_sel_time, >>> + [IPMI_CMD_GET_SDR_REP_INFO] = { get_sdr_rep_info }, >>> + [IPMI_CMD_RESERVE_SDR_REP] = { reserve_sdr_rep }, >>> + [IPMI_CMD_GET_SDR] = { get_sdr, 8 }, >>> + [IPMI_CMD_ADD_SDR] = { add_sdr }, >>> + [IPMI_CMD_CLEAR_SDR_REP] = { clear_sdr_rep, 8 }, >>> + [IPMI_CMD_GET_SEL_INFO] = { get_sel_info }, >>> + [IPMI_CMD_RESERVE_SEL] = { reserve_sel }, >>> + [IPMI_CMD_GET_SEL_ENTRY] = { get_sel_entry, 8 }, >>> + [IPMI_CMD_ADD_SEL_ENTRY] = { add_sel_entry, 18 }, >>> + [IPMI_CMD_CLEAR_SEL] = { clear_sel, 8 }, >>> + [IPMI_CMD_GET_SEL_TIME] = { get_sel_time, 6 }, >>> + [IPMI_CMD_SET_SEL_TIME] = { set_sel_time }, >>> }; >>> >>> static const IPMINetfn storage_netfn = { >> >