scrypt: fix panic on parameters <= 0

Providing 0 as argument for r or p results in a panic:
panic: runtime error: integer divide by zero

Providing negative values for r or p returns a misleading error:
scrypt: parameters are too large

This change avoids the panic and introduces a new error
that is returned when r or p are <= 0:
scrypt: parameters must be > 0

Change-Id: I68987b27d1eedd66644d2ec9436cba364fc1d46d
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/731780
Reviewed-by: Michael Pratt <mpratt@google.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Auto-Submit: Roland Shoemaker <roland@golang.org>
2 files changed
tree: 8ae802c545076b19fa5f72f44f8b303039aafa41
  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
  37. CONTRIBUTING.md
  38. go.mod
  39. go.sum
  40. LICENSE
  41. PATENTS
  42. README.md
README.md

Go Cryptography

Go Reference

This repository holds supplementary Go cryptography packages.

Report Issues / Send Patches

This repository uses Gerrit for code changes. To learn how to submit changes to this repository, see https://go.dev/doc/contribute.

The git repository is https://go.googlesource.com/crypto.

The main issue tracker for the crypto repository is located at https://go.dev/issues. Prefix your issue with “x/crypto:” in the subject line, so it is easy to find.

Note that contributions to the cryptography package receive additional scrutiny due to their sensitive nature. Patches may take longer than normal to receive feedback.