agent: Do not place a trailing NUL byte on S-expression
agent/pkdecrypt.c (agent_pkdecrypt): Avoid appending a trailing NUL
byte at the end of the generated S-expression.
In many cases, a canonical S-expression may have an embedded NUL
anyway (especially if it contains raw cryptographic key material or
other high-entropy bytestrings), so trying to treat a canonical
S-expression as a C string is likely to be dangerous -- better to not
leave any such expectations.
- GnuPG-bug-id: T4652
- Signed-off-by: Daniel Kahn Gillmor <email@example.com>