Differences
This shows you the differences between the selected revisions of the page.
| 2014-07-15 | 2014-07-23 | ||
| chokes on winadj is beta (martin) | 5.5.3 Bug 1091 Occasional RSA public key authentication failure (martin) | ||
| Line 69: | Line 69: | ||
| ===== Requires padding on SSH-2 RSA signatures ===== | ===== Requires padding on SSH-2 RSA signatures ===== | ||
| - | Versions below 3.3 of [[&openssh|OpenSSH]] require SSH-2 RSA signatures to be padded with zero bytes to the same length as the RSA key modulus. The SSH-2 draft specification says that an unpadded signature MUST be accepted, so this is a bug. A typical symptom of this problem is that WinSCP mysteriously fails RSA authentication once in every few hundred attempts, and falls back to passwords. | + | Versions below 3.3 of [[&openssh|OpenSSH]] and versions below 1.3.4d/1.3.5rc4 of ProFTPD/mod_sftp require SSH-2 RSA signatures to be padded with zero bytes to the same length as the RSA key modulus. The SSH-2 draft specification says that an unpadded signature MUST be accepted, so this is a bug. A typical symptom of this problem is that WinSCP mysteriously fails RSA authentication once in every few hundred attempts, and falls back to passwords. |
| - | If this bug is detected, WinSCP will pad its signatures in the way OpenSSH expects. If this bug is enabled when talking to a correct server, it is likely that no damage will be done, since correct servers usually still accept padded signatures because they're used to talking to OpenSSH. | + | If this bug is detected, WinSCP will pad its signatures in the way the buggy servers expect. If this bug is enabled when talking to a correct server, it is likely that no damage will be done, since correct servers usually still accept padded signatures because they're used to talking to OpenSSH. |
| This is an SSH-2-specific bug. | This is an SSH-2-specific bug. | ||