59 lines
1.8 KiB
Plaintext
59 lines
1.8 KiB
Plaintext
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SHA1 usage:
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-----------
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In the U-Boot Image for the pcs440ep board is a SHA1 checksum integrated.
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This SHA1 sum is used, to check, if the U-Boot Image in Flash is not
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corrupted.
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The following command is available:
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=> help sha1
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sha1 address len [addr] calculate the SHA1 sum [save at addr]
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-p calculate the SHA1 sum from the U-Boot image in flash and print
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-c check the U-Boot image in flash
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"sha1 -p"
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calculates and prints the SHA1 sum, from the Image stored in Flash
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"sha1 -c"
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check, if the SHA1 sum from the Image stored in Flash is correct
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It is possible to calculate a SHA1 checksum from a memoryrange with:
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"sha1 address len"
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If you want to store a new Image in Flash for the pcs440ep board,
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which has no SHA1 sum, you can do the following:
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a) cp the new Image on a position in RAM (here 0x300000)
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(for this example we use the Image from Flash, stored at 0xfffa0000 and
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0x60000 Bytes long)
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"cp.b fffa0000 300000 60000"
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b) Initialize the SHA1 sum in the Image with 0x00
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The SHA1 sum is stored in Flash at:
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CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN + SHA1_SUM_POS
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for the pcs440ep Flash: 0xfffa0000 + 0x60000 + -0x20
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= 0xffffffe0
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for the example in RAM: 0x300000 + 0x60000 + -0x20
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= 0x35ffe0
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note: a SHA1 checksum is 20 bytes long.
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"mw.b 35ffe0 0 14"
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c) now calculate the SHA1 sum from the memoryrange and write
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the calculated checksum at the right place:
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"sha1 300000 60000 35ffe0"
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Now you have a U-Boot-Image for the pcs440ep board with the correct SHA1 sum.
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If you do a "buildman -k pcs440ep" or a "make all" to get the U-Boot image,
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which will be found in ../current/ipam390/ - the correct SHA1 sum will be
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automagically included in the U-Boot image.
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Heiko Schocher, 11 Jul 2007
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