Previously we had decoded the asn.1 to get a public key, and then
discarded the asn.1 so that we had to re-encode the key to store it
in the onion_pkey field of a microdesc_t or routerinfo_t.
Now we can just do a tor_memdup() instead, which should be loads
faster.
Previously, we would decode the PEM wrapper for keys twice: once in
get_next_token, and once later in PEM decode. Now we just do all of
the wrapper and base64 stuff in get_next_token, and store the
base64-decoded part in the token object for keys and non-keys alike.
This change should speed up parsing slightly by letting us skip a
bunch of stuff in crypto_pk_read_*from_string(), including the tag
detection parts of pem_decode(), and an extra key allocation and
deallocation pair.
Retaining the base64-decoded part in the token object will allow us
to speed up our microdesc parsing, since it is the asn1 portion that
we actually want to retain.
The strcmp_len() function was somewhat misconceived, since we're
only using it to test whether a length+extent string is equal to a
NUL-terminated string or not. By simplifying it and making it
inlined, we should be able to make it a little faster.
(It *does* show up in profiles.)
Closes ticket 28856.
I believe we originally added this for "just in case" safety, but it
isn't actually needed -- we never copy uninitialized stack here.
What's more, this one memset is showing up on our startup profiles,
so we ought to remove it.
Closes ticket 28852.
teor
Nick Mathewson
George Kadianakis