Can we derive message From CRC
I have a 100Bytes of data and calculated CRC-64 on the same.
I have the CRC and 4 bytes of original data available (the 4 bytes are the last or first 4 bytes of data and we can choose it)
Is it possible to rebuild the data?
compression crc
asked Nov 16 '18 at 6:05
tkktkk
11
add a comment |
I have a 100Bytes of data and calculated CRC-64 on the same.
I have the CRC and 4 bytes of original data available (the 4 bytes are the last or first 4 bytes of data and we can choose it)
Is it possible to rebuild the data?
compression crc
asked Nov 16 '18 at 6:05
tkktkk
11
The data can't be rebuilt. You could set the unknown data to all zeroes except for 8 bytes and set the values of those 8 bytes to end up with a CRC-64 of zero.
– rcgldr
Nov 16 '18 at 6:33
add a comment |
I have a 100Bytes of data and calculated CRC-64 on the same.
I have the CRC and 4 bytes of original data available (the 4 bytes are the last or first 4 bytes of data and we can choose it)
Is it possible to rebuild the data?
compression crc
asked Nov 16 '18 at 6:05
tkktkk
11
I have a 100Bytes of data and calculated CRC-64 on the same.
I have the CRC and 4 bytes of original data available (the 4 bytes are the last or first 4 bytes of data and we can choose it)
Is it possible to rebuild the data?
compression crc
compression crc
asked Nov 16 '18 at 6:05
tkktkk
11
asked Nov 16 '18 at 6:05
tkktkk
11
asked Nov 16 '18 at 6:05
tkktkk
11
asked Nov 16 '18 at 6:05
tkktkk
11
asked Nov 16 '18 at 6:05
tkktkk
11
11
The data can't be rebuilt. You could set the unknown data to all zeroes except for 8 bytes and set the values of those 8 bytes to end up with a CRC-64 of zero.
– rcgldr
Nov 16 '18 at 6:33
add a comment |
The data can't be rebuilt. You could set the unknown data to all zeroes except for 8 bytes and set the values of those 8 bytes to end up with a CRC-64 of zero.
– rcgldr
Nov 16 '18 at 6:33
The data can't be rebuilt. You could set the unknown data to all zeroes except for 8 bytes and set the values of those 8 bytes to end up with a CRC-64 of zero.
– rcgldr
Nov 16 '18 at 6:33
The data can't be rebuilt. You could set the unknown data to all zeroes except for 8 bytes and set the values of those 8 bytes to end up with a CRC-64 of zero.
– rcgldr
Nov 16 '18 at 6:33
add a comment |
1 Answer
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No.
You would be able to do so only if the number of unknown bytes was less than or equal to the number of bytes in the CRC (which is eight). You have 96 unknown bytes.
answered Nov 17 '18 at 7:37
Mark AdlerMark Adler
59.7k867112
add a comment |
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1 Answer
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1 Answer
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active
oldest
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oldest
votes
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oldest
votes
No.
You would be able to do so only if the number of unknown bytes was less than or equal to the number of bytes in the CRC (which is eight). You have 96 unknown bytes.
answered Nov 17 '18 at 7:37
Mark AdlerMark Adler
59.7k867112
add a comment |
No.
You would be able to do so only if the number of unknown bytes was less than or equal to the number of bytes in the CRC (which is eight). You have 96 unknown bytes.
answered Nov 17 '18 at 7:37
Mark AdlerMark Adler
59.7k867112
add a comment |
No.
You would be able to do so only if the number of unknown bytes was less than or equal to the number of bytes in the CRC (which is eight). You have 96 unknown bytes.
answered Nov 17 '18 at 7:37
Mark AdlerMark Adler
59.7k867112
No.
You would be able to do so only if the number of unknown bytes was less than or equal to the number of bytes in the CRC (which is eight). You have 96 unknown bytes.
answered Nov 17 '18 at 7:37
Mark AdlerMark Adler
59.7k867112
answered Nov 17 '18 at 7:37
Mark AdlerMark Adler
59.7k867112
answered Nov 17 '18 at 7:37
Mark AdlerMark Adler
59.7k867112
answered Nov 17 '18 at 7:37
Mark AdlerMark Adler
59.7k867112
59.7k867112
add a comment |
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The data can't be rebuilt. You could set the unknown data to all zeroes except for 8 bytes and set the values of those 8 bytes to end up with a CRC-64 of zero.
– rcgldr
Nov 16 '18 at 6:33