Re: RSA exponent
Larry Bugbee <[email protected]>
| Newsgroups | gmane.comp.python.cryptography |
|---|---|
| Message-ID | <[email protected]> |
Thanks Dan, that made things work a LOT better. It seems the 4-byte prefix applies only to elements extracted from the key objects and not to other binary strings such as hashes and signatures. Now for the two-bit rhetorical question. Why only the key elements? Shouldn't the key elements follow the same set of rules? Anyway, my thanks, Larry On Aug 3, 2004, at 3:42 PM, Dan Berger wrote: > It's likely because OpenSSL (and the M2 wrapper) are returning an MPI - > which has it's length as the first four bytes and remainder being the > number in big-endian byte order. > > On Tue, 2004-08-03 at 21:39 +0200, Larry Bugbee wrote: >> I could use some help... >> >> When I generate a RSA key pair I use 65537 as the exponent. Later >> when I go >> to extract the exponent I get 50397185. In hex it's actually 00 00 >> 00 03 01 >> 00 01, but if I discard the 4 high order bytes, 01 00 01 evaluates to >> 65537. >> Perhaps you have a suggestion? [snip]