Recently PAMELA collaboration published the cosmic nuclei and electron spectra with high precision, together with the cosmic antiproton data updated, and the Fermi-LAT collaboration also updated the measurement of the total e^+e^- spectrum to lower energies. In this paper we develop a Markov Chain Monte Carlo (MCMC) package CosRayMC, based on the GALPROP cosmic ray propagation model to study the implications of these new data. It is found that if only the background electrons and secondary

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... rons are considered, the fit is very bad with χ_ red^2 ≈ 3.68. Taking into account the extra e^+e^- sources of pulsars or dark matter annihilation we can give much better fit to these data, with the minimum χ_ red^2 ≈ 0.83. This means the extra sources are necessary with a very high significance in order to fit the data. However, the data show little difference between pulsar and dark matter scenarios. Both the background and extra source parameters are well constrained with this MCMC method. Including the antiproton data, we further constrain the branching ratio of dark matter annihilation into quarks B_q<0.5 uncertainties of the present study are discussed.