1016836 - RSA_PrivateKeyCheck not robust against 'hostile' inputs, crash

Status: RESOLVED FIXED

(NSS :: Libraries, defect, P1)

Description

[Ryan Sleevi]

The freebl function RSA_PrivateKeyCheck, used to check parameter consistency, is not robust against hostile input, in that it always calls SECITEM_TO_MPINT on the supplied parameters.

The related function, RSA_PopulatePrivateKey, is more consistent, by only calling SECITEM_TO_MPINT when (param).data is non-NULL, and ensuring the operation fails if the necessary parameters are not present.

Comment 1

[Ryan Sleevi]

Attachment: Robustness

Bob,

This matches our discussion on the call, which was to change RSA_PrivateKeyCheck to require all of the parameters be supplied when importing a key to softoken, rather than recomputing the CRT factors.

For robustness sake, if any of the parameters are missing, it will early return - to avoid SECITEM_TO_MPINT blowing up.

The softoken side is in Bug 1016811.

Comment 2

[Ryan Sleevi]

Fixed in https://hg.mozilla.org/projects/nss/rev/7dc83fd04549

Comment 3

[Wan-Teh Chang]

Attachment: Remove the unused function swap_in_key_value.

All calls to swap_in_key_value were removed in the previous patch.

Comment 4

[Ryan Sleevi]

Comment on attachment 8436365 [details] [diff] [review]
Remove the unused function swap_in_key_value.

Review of attachment 8436365 [details] [diff] [review]:
-----------------------------------------------------------------

r+

Comment 5

[Wan-Teh Chang]

Comment on attachment 8436365 [details] [diff] [review]
Remove the unused function swap_in_key_value.

Patch checked in: https://hg.mozilla.org/projects/nss/rev/b066f111ac16

Comment 6

[Wan-Teh Chang]

Attachment: Remove stale comments from RSA_PrivateKeyCheck

These comments were more useful when RSA_PrivateKeyCheck
would fix up the input RSAPrivateKey. Now that RSA_PrivateKeyCheck
only performs checks, it is not necessary to mention which
errors can be recovered from and which cannot.

Comment 7

[Wan-Teh Chang]

Comment on attachment 8440180 [details] [diff] [review]
Remove stale comments from RSA_PrivateKeyCheck

Patch checked in: https://hg.mozilla.org/projects/nss/rev/b07697c94038