19 lines
970 B
Text
19 lines
970 B
Text
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The libmerkletree library implements Merkle tree calculation, and also
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includes some higher-level functions to verify a file against a
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previously-generated Merkle tree.
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A Merkle tree is a hash tree calculated across blocks in data. Any
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block size can be specified in this implementation. A digest is
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calculated across each block in the data, and then a digest is
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calculated across blocks of the checksums, and this continues until
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only one block of digest exists. The hierarchical nature of this
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allows individual blocks of a file to be verified, even if other parts
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of the file have been modified. A degenerate case, in which the data
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is less than the blocksize, will mean that a single digest value for
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the block is calculated. This will be the same as the digest
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algorithm applied to the whole file.
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The digest calculations themselves are done by the libmultigest(3)
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library, and allow concatenation of multiple digests to produce a
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single large digest value.
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