sha512hmac(8) [centos man page]
sha512hmac(8) System Administrator's Manual sha512hmac(8) NAME
sha512hmac - compute and check HMAC values SYNOPSIS
sha512hmac [OPTIONS] [-u | -k keyfile | -K key] [-c file [-q] | file [...] ] DESCRIPTION
The sha512hmac command can compute and/or verify HMAC and unkeyed checksum values for the contents of files. Variations such as sha384hmac, sha256hmac, and sha1hmac all operate similarly except that they use different digest algorithms. SELF-TEST As a safety measure, the tool will always attempt to verify a previously- computed HMAC over itself with the contents of a second file (sha512hmac.hmac for sha512hmac, and a similarly-named file for each variation) before processing any other files, and will exit with an error if the second file either cannot be read or does not match the computed value. OPTIONS
-c Check that the HMAC values and names listed in the specified file(s) are correct for the files which are available. The format of the files should match the output which the tool produces when computing the values: a hex-encoded HMAC value and then a filename, separated by whitespace. -q Suppress any output when checking values. -d cfgdir Specify the configuration directory to be used by the NSS library. The default location is /etc/pki/nssdb. -h algorithm Generate the HMAC value using a non-default hashing algorithm. The default is determined by the name used to invoke the tool (sha1hmac, sha256hmac, etc.). If no default can be derived this way, the default setting will be sha512. Specify help or another invalid value to obtain a list of recognized algorithms. -u Generate an unkeyed checksum instead of an HMAC. The output produced by the tool should then be comparable to that of sha1sum and related tools. -k filename Use the contents of the specified file as the secret key used in computing the HMAC values. If no key file or text is specified, a hard-coded default value is used. This option should always be used. -K text Use the text of the argument as the secret key used in computing the HMAC values. If no key file or text is specified, a hard-coded default value is used. -b Process file contents in binary mode, marking output as such by prefixing filenames with *. This option is not expected to have any other meaningful effect. -t bits Truncate HMAC values to a given length when computing or verifying them. -S Generate an HMAC over the tool itself and output it on standard out. This is a bootstrapping option which is not expected to be used. -P Attempt to pass all input files through prelink -y before processing their contents. The tool always attempts to do so when comput- ing or performing a self-check. EXAMPLES
Example output from sha1hmac, for files on the developer's system: e64db5e8a9b8a40091e5302fa4de0bfc6c5d19d0 /etc/passwd e7d93a2c70ec4d7720c6f2b033c1e5ea19f2d677 /etc/group d732d6df77114ea6b81a43d64655f86b1e5ee925 /etc/services ad92162bef979054a75d1f3510e6b05902bec641 /etc/hosts SEE ALSO
fipshmac(1), fipscheck(1), prelink(8) BUGS
Probably, but let's hope not. If you find any, please either report them in the bug database at http://bugzilla.redhat.com/ against the "hmaccalc" component, or in the trac instance at https://fedorahosted.org/hmaccalc/. AUTHOR
Nalin Dahyabhai <nalin@redhat.com> hmaccalc 0.9.13 2009/03/19 sha512hmac(8)
Check Out this Related Man Page
DGST(1) OpenSSL DGST(1) NAME
dgst, md5, md4, md2, sha1, sha, mdc2, ripemd160 - message digests LIBRARY
libcrypto, -lcrypto SYNOPSIS
openssl dgst [-md5|-md4|-md2|-sha1|-sha|-mdc2|-ripemd160|-dss1] [-c] [-d] [-hex] [-binary] [-out filename] [-sign filename] [-keyform arg] [-passin arg] [-verify filename] [-prverify filename] [-signature filename] [-hmac key] [file...] [md5|md4|md2|sha1|sha|mdc2|ripemd160] [-c] [-d] [file...] DESCRIPTION
The digest functions output the message digest of a supplied file or files in hexadecimal form. They can also be used for digital signing and verification. OPTIONS
-c print out the digest in two digit groups separated by colons, only relevant if hex format output is used. -d print out BIO debugging information. -hex digest is to be output as a hex dump. This is the default case for a "normal" digest as opposed to a digital signature. -binary output the digest or signature in binary form. -out filename filename to output to, or standard output by default. -sign filename digitally sign the digest using the private key in "filename". -keyform arg Specifies the key format to sign digest with. Only PEM and ENGINE formats are supported by the dgst command. -engine id Use engine id for operations (including private key storage). This engine is not used as source for digest algorithms, unless it is also specified in the configuration file. -sigopt nm:v Pass options to the signature algorithm during sign or verify operations. Names and values of these options are algorithm-specific. -passin arg the private key password source. For more information about the format of arg see the PASS PHRASE ARGUMENTS section in openssl(1). -verify filename verify the signature using the the public key in "filename". The output is either "Verification OK" or "Verification Failure". -prverify filename verify the signature using the the private key in "filename". -signature filename the actual signature to verify. -hmac key create a hashed MAC using "key". -mac alg create MAC (keyed Message Authentication Code). The most popular MAC algorithm is HMAC (hash-based MAC), but there are other MAC algorithms which are not based on hash, for instance gost-mac algorithm, supported by ccgost engine. MAC keys and other options should be set via -macopt parameter. -macopt nm:v Passes options to MAC algorithm, specified by -mac key. Following options are supported by both by HMAC and gost-mac: key:string Specifies MAC key as alphnumeric string (use if key contain printable characters only). String length must conform to any restrictions of the MAC algorithm for example exactly 32 chars for gost-mac. hexkey:string Specifies MAC key in hexadecimal form (two hex digits per byte). Key length must conform to any restrictions of the MAC algorithm for example exactly 32 chars for gost-mac. -rand file(s) a file or files containing random data used to seed the random number generator, or an EGD socket (see RAND_egd(3)). Multiple files can be specified separated by a OS-dependent character. The separator is ; for MS-Windows, , for OpenVMS, and : for all others. file... file or files to digest. If no files are specified then standard input is used. NOTES
The digest of choice for all new applications is SHA1. Other digests are however still widely used. If you wish to sign or verify data using the DSA algorithm then the dss1 digest must be used. A source of random numbers is required for certain signing algorithms, in particular DSA. The signing and verify options should only be used if a single file is being signed or verified. 1.0.1i 2009-07-20 DGST(1)