static TEE_Result fTPM_Emulate_PPI()

in TAs/optee_ta/fTPM/fTPM.c [329:389]

• 49 lines of code
• 8 McCabe index (conditional complexity)

static TEE_Result fTPM_Emulate_PPI(uint32_t  param_types,
                                   TEE_Param params[4]
)
{
    uint8_t *cmdBuf, *respBuf;
    uint32_t cmdLen, respLen;
    uint32_t exp_param_types = TEE_PARAM_TYPES(TEE_PARAM_TYPE_MEMREF_INPUT,
                               TEE_PARAM_TYPE_MEMREF_INOUT,
                               TEE_PARAM_TYPE_NONE,
                               TEE_PARAM_TYPE_NONE);

    // Validate parameter types
    if (param_types != exp_param_types) {
#ifdef fTPMDebug
        IMSG("Bad param type(s)\n");
#endif
        return TEE_ERROR_BAD_PARAMETERS;
    }

    // Sanity check our buffer sizes
    if ((params[0].memref.size == 0) ||
        (params[1].memref.size == 0) ||
        (params[0].memref.size > MAX_COMMAND_SIZE) ||
        (params[1].memref.size > MAX_RESPONSE_SIZE)) {
#ifdef fTPMDebug
        IMSG("Bad param size(s)\n");
#endif
        return TEE_ERROR_BAD_PARAMETERS;
    }

    // Copy command locally
    memcpy(fTPMCommand, params[0].memref.buffer, params[0].memref.size);

    cmdBuf = fTPMCommand;
    cmdLen = params[0].memref.size;

    respBuf = (uint8_t *)(params[1].memref.buffer);
    respLen = params[1].memref.size;

    // Pass along to platform PPI processing
    if (_admin__PPIRequest(cmdLen, cmdBuf, &respLen, &respBuf)) {
#ifdef fTPMDebug
        DMSG("Handled PPI command via TA interface\n");
#endif
    }
    else {
#ifdef fTPMDebug
        IMSG("Failed to handle PPI command via TA interface\n");
#endif
    }

    if (respLen > params[1].memref.size) {
#ifdef fTPMDebug
        IMSG("Insufficient buffer length RS: 0x%x > BL: 0x%x\n", respLen, params[1].memref.size);
#endif
        return TEE_ERROR_SHORT_BUFFER;
    }

    params[1].memref.size = respLen;
    return TEE_SUCCESS;
}