| @@ -816,5 +816,45 @@ Command-line options |
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Test whether the zipfile is valid or not. |
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+Decompression pitfalls |
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+---------------------- |
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+ |
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+The extraction in zipfile module might fail due to some pitfalls listed below. |
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+ |
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+From file itself |
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+~~~~~~~~~~~~~~~~ |
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+ |
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+Decompression may fail due to incorrect password / CRC checksum / ZIP format or |
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+unsupported compression method / decryption. |
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+ |
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+File System limitations |
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+~~~~~~~~~~~~~~~~~~~~~~~ |
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+ |
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+Exceeding limitations on different file systems can cause decompression failed. |
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+Such as allowable characters in the directory entries, length of the file name, |
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+length of the pathname, size of a single file, and number of files, etc. |
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+ |
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+Resources limitations |
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+~~~~~~~~~~~~~~~~~~~~~ |
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+ |
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+The lack of memory or disk volume would lead to decompression |
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+failed. For example, decompression bombs (aka `ZIP bomb`_) |
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+apply to zipfile library that can cause disk volume exhaustion. |
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+ |
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+Interruption |
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+~~~~~~~~~~~~ |
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+ |
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+Interruption during the decompression, such as pressing control-C or killing the |
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+decompression process may result in incomplete decompression of the archive. |
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+ |
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+Default behaviors of extraction |
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+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
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+ |
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+Not knowing the default extraction behaviors |
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+can cause unexpected decompression results. |
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+For example, when extracting the same archive twice, |
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+it overwrites files without asking. |
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+ |
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+.. _ZIP bomb: https://en.wikipedia.org/wiki/Zip\_bomb |
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.. _PKZIP Application Note: https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT |