Voltage-based Covert Channels using FPGAs

FPGAs are increasingly used in cloud applications and being integrated into Systems-on-Chip (SoCs). For these systems, various side-channel attacks on cryptographic implementations have been reported, motivating to apply proper countermeasures. Beyond cryptographic implementations, maliciously introduced covert channel receivers and transmitters can allow to exfiltrate other secret information from the FPGA. In this paper, we present a fast covert channel on FPGAs, which exploits the on-chip power distribution network. This can be achieved without any logical connection between the transmitter and receiver blocks. Compared to a recently published covert channel with an estimated 4.8 Mbit/s transmission speed, we show 8 Mbit/s transmission and reduced errors from around 3% to less than 0.003%. Furthermore, we demonstrate proper transmissions of word-size messages and test the channel in the presence of noise generated from other residing tenants\u27 modules in the FPGA. When we place and operate other co-tenant modules that require 85% of the total FPGA area, the error rate increases to 0.02%, depending on the platform and setup. This error rate is still reasonably low for a covert channel. Overall, the transmitter and receiver work with less than 3-5% FPGA LUT resources together. We also show the feasibility of other types of covert channel transmitters, in the form of synchronous circuits within the FPGA

Evaluating the impact of a common elements-based intervention to improve maternal psychological well-being and mother-infant interaction in rural Pakistan: study protocol for a randomised controlled trial.

IntroductionMillions of children in low resource settings are at high risk of poor development due to factors such as under nutrition, inadequate stimulation and maternal depression. Evidence-based interventions to address these risk factors exist, but often as a separate and overlapping package. The current study aims to evaluate the effectiveness of a common elements-based intervention to improve mother-infant interaction at 12 months post-partum.Method and analysisA two-arm, single-blinded, individual randomised controlled trial is being carried out in the community settings of the rural subdistrict of Gujar Khan in Rawalpindi, Pakistan. 250 pregnant women in third trimester with distress (Self-Reporting Questionnaire, cut-off score >9) have been randomised on 1:1 allocation ratio into intervention (n=125) and treatment-as-usual arms (n=125). The participants in the intervention arm will receive 15 individual sessions of intervention on a monthly basis by non-specialist facilitators. The intervention involves components of early stimulation, learning through play, responsive feeding, guided discovery using pictures, behavioural activation and problem solving. The primary outcome is caregiver-infant interaction at 12 months postpartum. The secondary outcomes include maternal psychological well-being, quality of life, social support and empowerment. Infant secondary outcomes include growth, nutrition and development. The data will be collected at baseline, 6 and 12 months postpartum. A qualitative process evaluation will be conducted to inform the feasibility of intervention delivery.EthicsEthics approval for the present study was obtained from the Human Development Research Foundation Institutional Review Board, Islamabad Pakistan.DisseminationIf proven effective, the study will contribute to scale-up care for maternal and child mental health in low resource settings, globally. The findings of the present study will be published in peer-reviewed journals and presented at conferences and community forums.Trial registration numberNCT04252807