static TEE_Result fTPM_Submit_Command()

in TAs/optee_ta/fTPM/fTPM.c [259:324]

• 50 lines of code
• 9 McCabe index (conditional complexity)

static TEE_Result fTPM_Submit_Command(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);

    DMSG("fTPM submit command"); 
    // 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);

    // Pull the command length from the actual TPM command. The memref size
    // field descibes the buffer containing the command, not the command.
    cmdBuf = fTPMCommand;
    cmdLen = BYTE_ARRAY_TO_UINT32((uint8_t *)&(cmdBuf[2]));
    // Sanity check cmd length included in TPM command
    if (cmdLen > params[0].memref.size) {
        return TEE_ERROR_BAD_PARAMETERS;
    }
    respBuf = (uint8_t *)(params[1].memref.buffer);
    respLen = params[1].memref.size;
    // Check if this is a PPI Command
    if (!_admin__PPICommand(cmdLen, cmdBuf, &respLen, &respBuf)) {
        // If not, pass through to TPM
        ExecuteCommand(cmdLen, cmdBuf, &respLen, &respBuf);
    }
    // Unfortunately, this cannot be done until after we have our response in
    // hand. We will, however, make an effort to return at least a portion of
    // the response along with TEE_ERROR_SHORT_BUFFER.
    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;
    }
#ifdef fTPMDebug
    DMSG("Success, RS: 0x%x\n", respLen);
#endif

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