nCFB和nOFB，我可以找到：

This is one reference to nCFB and nOFB that I could find:

请注意，文件的其余部分的CFB和OFB表示8位CFB或OFB模式。 nOFB和nCFB模式表示n位OFB / CFB模式， n用于表示算法的块大小。

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nOFB：输出反馈模式（以nbit为单位）。 n是算法块的大小。这是一个从块密码实现的同步流密码。它是用于噪声线，因为损坏的密文块不会破坏随后的明文块。此模式以流形式运行。

nOFB: The Output-Feedback Mode (in nbit). n Is the size of the block of the algorithm. This is a synchronous stream cipher implemented from a block cipher. It is intended for use in noisy lines, because corrupted ciphertext blocks do not corrupt the plaintext blocks that follow. This mode operates in streams.

nCFB：密码反馈模式（以n位表示）。 n是算法块的大小。这是从块密码实现的自同步流密码。此模式以流形式运行。

nCFB: The Cipher-Feedback Mode (in nbit). n Is the size of the block of the algorithm. This is a self synchronizing stream cipher implemented from a block cipher. This mode operates in streams.

http://mcrypt.hellug.gr/lib/mcrypt.3.html