This paper considers the two-user Gaussian interference channel in the presence of adversarial
jammers. We first provide a general model including an arbitrary number of jammers, and show that
its capacity region is equivalent to that of a simplified model in which the received jamming signal at
each decoder is independent. Next, existing outer and inner bounds for two-user Gaussian interference
channel are generalized for this simplified jamming model. We show that for certain problem parameters,
precisely the same bounds hold, but with the noise variance increased by the received power of the
jammer at each receiver. Thus, the jammers can do no better than to transmit Gaussian noise. For these
problem parameters, this allows us to recover the half-bit theorem. 
Furthermore, we determine the symmetric degrees of freedom where the signal-to-noise, interference-
to-noise and jammer-to-noise ratios are all tend to infinity. Moreover, we show that, if the jammer has
greater received power than the legitimate user, symmetrizability makes the capacity zero. The proof of
the outer bound is straightforward, while the inner bound generalizes the Han-Kobayashi rate splitting
scheme. As a novel aspect, the inner bound takes advantage of the common message acting as common
randomness for the private message; hence, the jammer cannot symmetrize only the private codeword
without being detected. This complication requires an extra condition on the signal power, so that in
general our inner bound is not identical to the Han-Kobayashi bound.