cryptobyte: fix ReadOptionalASN1Boolean

ReadOptionalASN1Boolean was completely broken, it would only work when
there were two BOOLEAN fields in a row, with the first being OPTIONAL
(which is itself invalid ASN.1 due to the ambiguity). This fixes it
to properly expect a BOOLEAN wrapped in a context-specific tag, as is
the case for all of the other ReadOptionalASN1* methods, and updates
its doc string.

This is a breaking change as it requires adding the tag field to
properly support context-specific tags. Given the method would
previously not work this seems like a reasonable breakage.

Fixes golang/go#43019

Change-Id: I42398256216c59988e249c90bc7aa668f64df945
Reviewed-by: Filippo Valsorda <>
Reviewed-by: Damien Neil <>
LUCI-TryBot-Result: Go LUCI <>
Auto-Submit: Roland Shoemaker <>
2 files changed
tree: a52e5a4c78bdd8c5ce2eae4d2f613fb6faa6e73f
  1. acme/
  2. argon2/
  3. bcrypt/
  4. blake2b/
  5. blake2s/
  6. blowfish/
  7. bn256/
  8. cast5/
  9. chacha20/
  10. chacha20poly1305/
  11. cryptobyte/
  12. curve25519/
  13. ed25519/
  14. hkdf/
  15. internal/
  16. md4/
  17. nacl/
  18. ocsp/
  19. openpgp/
  20. otr/
  21. pbkdf2/
  22. pkcs12/
  23. poly1305/
  24. ripemd160/
  25. salsa20/
  26. scrypt/
  27. sha3/
  28. ssh/
  29. tea/
  30. twofish/
  31. x509roots/
  32. xtea/
  33. xts/
  34. .gitattributes
  35. .gitignore
  36. codereview.cfg
  38. go.mod
  39. go.sum

Go Cryptography

Go Reference

This repository holds supplementary Go cryptography libraries.


The easiest way to install is to run go get -u You can also manually git clone the repository to $GOPATH/src/

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