"Do you trust your chipsets?"

Certainly not. I do believe that the recent tiny bytes sequences in any TCP (UDP ?) packet that can lock Intel ethernet cards is actually a backdoor allowing the state to perform DoS at will. I do also believe Huawei and ZTE are state-sponsored espionage companies (I've certainly seen weird things like a keylogger inside a 3G Huawei USB device sold I bought in Europe).

But I do believe that even if I'm, say, a Debian or OpenBSD dev working on OpenSSL it's amazingly complicated for the chipset to modify source code and be able to make to the DVCS unnoticed. I also think that as long as the source code isn't corrupted there are ways to create non-backdoored builds.

It's the same thing with program provers that can verify that certain piece of code are guaranteed to be free of buffer overrun/overflow: what proves that the compiler itself hasn't been tampered with? But still... With DVCSes and many eyeballs I'm not that much concerned about the compilers typically used nowadays to be tampered with.