SHA1(1) OpenBSD Reference Manual SHA1(1)NAMEsha1 - calculate a message-digest fingerprint (checksum) for a file
SYNOPSISsha1 [-bpqrtx] [-c [checklist ...]] [-s string] [file ...]
DESCRIPTIONsha1 takes as input a message of arbitrary length and produces as output
a 160-bit "fingerprint" or "message digest" of the input. It is
conjectured that it is computationally infeasible to produce two messages
having the same message digest, or to produce any message having a given
prespecified target message digest.
The SHA-1 algorithm is intended for digital signature applications, where
a large file must be "compressed" in a secure manner before being
encrypted with a private (secret) key under a public-key cryptosystem
such as RSA.
The options are as follows:
-b Output checksums in base64 notation, not hexadecimal.
-c [checklist ...]
Compares all checksums contained in the file checklist with newly
computed checksums for the corresponding files. Output consists
of the digest used, the file name, and an OK or FAILED for the
result of the comparison. This will validate any of the
supported checksums (see cksum(1)). If no file is given, stdin
is used.
-p Echoes stdin to stdout and appends the SHA-1 sum to stdout.
-q Only print the checksum (quiet mode).
-r Reverse the format of the hash algorithm output, making it match
the output format used by cksum(1).
-s string
Prints a checksum of the given string.
-t Runs a built-in time trial. Specifying -t multiple times results
in the number of rounds being multiplied by 10 for each
additional flag.
-x Runs a built-in test script.
The SHA-1 sum of each file listed on the command line is printed after
the options are processed.
The sha1 command is shorthand for
cksum -asha1
The cksum(1) command can also be used to compute digests from the SHA-2
family: sha256, sha384 and sha512.
EXIT STATUS
The sha1 utility exits 0 on success, and >0 if an error occurs.
SEE ALSOcksum(1), md5(1), sha256(1)
J. Burrows, The Secure Hash Standard, FIPS PUB 180-1.
D. Eastlake and P. Jones, US Secure Hash Algorithm 1, RFC 3174.
OpenBSD 4.9 September 3, 2010 OpenBSD 4.9