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856 lines
26 KiB
856 lines
26 KiB
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=pod
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=head1 NAME
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x509 - Certificate display and signing utility
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=head1 SYNOPSIS
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B<openssl> B<x509>
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[B<-inform DER|PEM|NET>]
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[B<-outform DER|PEM|NET>]
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[B<-keyform DER|PEM>]
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[B<-CAform DER|PEM>]
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[B<-CAkeyform DER|PEM>]
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[B<-in filename>]
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[B<-out filename>]
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[B<-serial>]
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[B<-hash>]
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[B<-subject_hash>]
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[B<-issuer_hash>]
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[B<-subject>]
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[B<-issuer>]
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[B<-nameopt option>]
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[B<-email>]
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[B<-ocsp_uri>]
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[B<-startdate>]
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[B<-enddate>]
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[B<-purpose>]
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[B<-dates>]
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[B<-modulus>]
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[B<-fingerprint>]
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[B<-alias>]
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[B<-noout>]
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[B<-trustout>]
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[B<-clrtrust>]
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[B<-clrreject>]
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[B<-addtrust arg>]
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[B<-addreject arg>]
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[B<-setalias arg>]
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[B<-days arg>]
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[B<-set_serial n>]
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[B<-signkey filename>]
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[B<-x509toreq>]
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[B<-req>]
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[B<-CA filename>]
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[B<-CAkey filename>]
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[B<-CAcreateserial>]
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[B<-CAserial filename>]
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[B<-text>]
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[B<-C>]
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[B<-md2|-md5|-sha1|-mdc2>]
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[B<-clrext>]
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[B<-extfile filename>]
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[B<-extensions section>]
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[B<-engine id>]
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=head1 DESCRIPTION
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The B<x509> command is a multi purpose certificate utility. It can be
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used to display certificate information, convert certificates to
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various forms, sign certificate requests like a "mini CA" or edit
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certificate trust settings.
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Since there are a large number of options they will split up into
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various sections.
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=head1 OPTIONS
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=head2 INPUT, OUTPUT AND GENERAL PURPOSE OPTIONS
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=over 4
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=item B<-inform DER|PEM|NET>
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This specifies the input format normally the command will expect an X509
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certificate but this can change if other options such as B<-req> are
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present. The DER format is the DER encoding of the certificate and PEM
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is the base64 encoding of the DER encoding with header and footer lines
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added. The NET option is an obscure Netscape server format that is now
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obsolete.
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=item B<-outform DER|PEM|NET>
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This specifies the output format, the options have the same meaning as the
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B<-inform> option.
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=item B<-in filename>
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This specifies the input filename to read a certificate from or standard input
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if this option is not specified.
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=item B<-out filename>
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This specifies the output filename to write to or standard output by
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default.
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=item B<-md2|-md5|-sha1|-mdc2>
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the digest to use. This affects any signing or display option that uses a message
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digest, such as the B<-fingerprint>, B<-signkey> and B<-CA> options. If not
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specified then SHA1 is used. If the key being used to sign with is a DSA key
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then this option has no effect: SHA1 is always used with DSA keys.
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=item B<-engine id>
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specifying an engine (by its unique B<id> string) will cause B<x509>
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to attempt to obtain a functional reference to the specified engine,
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thus initialising it if needed. The engine will then be set as the default
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for all available algorithms.
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=back
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=head2 DISPLAY OPTIONS
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Note: the B<-alias> and B<-purpose> options are also display options
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but are described in the B<TRUST SETTINGS> section.
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=over 4
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=item B<-text>
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prints out the certificate in text form. Full details are output including the
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public key, signature algorithms, issuer and subject names, serial number
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any extensions present and any trust settings.
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=item B<-certopt option>
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customise the output format used with B<-text>. The B<option> argument can be
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a single option or multiple options separated by commas. The B<-certopt> switch
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may be also be used more than once to set multiple options. See the B<TEXT OPTIONS>
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section for more information.
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=item B<-noout>
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this option prevents output of the encoded version of the request.
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=item B<-modulus>
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this option prints out the value of the modulus of the public key
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contained in the certificate.
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=item B<-serial>
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outputs the certificate serial number.
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=item B<-subject_hash>
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outputs the "hash" of the certificate subject name. This is used in OpenSSL to
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form an index to allow certificates in a directory to be looked up by subject
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name.
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=item B<-issuer_hash>
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outputs the "hash" of the certificate issuer name.
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=item B<-hash>
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synonym for "-subject_hash" for backward compatibility reasons.
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=item B<-subject_hash_old>
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outputs the "hash" of the certificate subject name using the older algorithm
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as used by OpenSSL versions before 1.0.0.
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=item B<-issuer_hash_old>
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outputs the "hash" of the certificate issuer name using the older algorithm
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as used by OpenSSL versions before 1.0.0.
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=item B<-subject>
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outputs the subject name.
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=item B<-issuer>
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outputs the issuer name.
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=item B<-nameopt option>
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option which determines how the subject or issuer names are displayed. The
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B<option> argument can be a single option or multiple options separated by
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commas. Alternatively the B<-nameopt> switch may be used more than once to
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set multiple options. See the B<NAME OPTIONS> section for more information.
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=item B<-email>
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outputs the email address(es) if any.
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=item B<-ocsp_uri>
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outputs the OCSP responder address(es) if any.
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=item B<-startdate>
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prints out the start date of the certificate, that is the notBefore date.
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=item B<-enddate>
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prints out the expiry date of the certificate, that is the notAfter date.
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=item B<-dates>
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prints out the start and expiry dates of a certificate.
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=item B<-fingerprint>
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prints out the digest of the DER encoded version of the whole certificate
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(see digest options).
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=item B<-C>
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this outputs the certificate in the form of a C source file.
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=back
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=head2 TRUST SETTINGS
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Please note these options are currently experimental and may well change.
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A B<trusted certificate> is an ordinary certificate which has several
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additional pieces of information attached to it such as the permitted
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and prohibited uses of the certificate and an "alias".
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Normally when a certificate is being verified at least one certificate
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must be "trusted". By default a trusted certificate must be stored
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locally and must be a root CA: any certificate chain ending in this CA
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is then usable for any purpose.
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Trust settings currently are only used with a root CA. They allow a finer
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control over the purposes the root CA can be used for. For example a CA
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may be trusted for SSL client but not SSL server use.
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See the description of the B<verify> utility for more information on the
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meaning of trust settings.
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Future versions of OpenSSL will recognize trust settings on any
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certificate: not just root CAs.
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=over 4
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=item B<-trustout>
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this causes B<x509> to output a B<trusted> certificate. An ordinary
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or trusted certificate can be input but by default an ordinary
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certificate is output and any trust settings are discarded. With the
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B<-trustout> option a trusted certificate is output. A trusted
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certificate is automatically output if any trust settings are modified.
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=item B<-setalias arg>
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sets the alias of the certificate. This will allow the certificate
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to be referred to using a nickname for example "Steve's Certificate".
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=item B<-alias>
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outputs the certificate alias, if any.
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=item B<-clrtrust>
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clears all the permitted or trusted uses of the certificate.
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=item B<-clrreject>
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clears all the prohibited or rejected uses of the certificate.
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=item B<-addtrust arg>
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adds a trusted certificate use. Any object name can be used here
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but currently only B<clientAuth> (SSL client use), B<serverAuth>
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(SSL server use) and B<emailProtection> (S/MIME email) are used.
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Other OpenSSL applications may define additional uses.
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=item B<-addreject arg>
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adds a prohibited use. It accepts the same values as the B<-addtrust>
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option.
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=item B<-purpose>
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this option performs tests on the certificate extensions and outputs
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the results. For a more complete description see the B<CERTIFICATE
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EXTENSIONS> section.
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=back
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=head2 SIGNING OPTIONS
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The B<x509> utility can be used to sign certificates and requests: it
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can thus behave like a "mini CA".
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=over 4
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=item B<-signkey filename>
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this option causes the input file to be self signed using the supplied
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private key.
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If the input file is a certificate it sets the issuer name to the
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subject name (i.e. makes it self signed) changes the public key to the
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supplied value and changes the start and end dates. The start date is
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set to the current time and the end date is set to a value determined
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by the B<-days> option. Any certificate extensions are retained unless
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the B<-clrext> option is supplied.
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If the input is a certificate request then a self signed certificate
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is created using the supplied private key using the subject name in
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the request.
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=item B<-clrext>
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delete any extensions from a certificate. This option is used when a
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certificate is being created from another certificate (for example with
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the B<-signkey> or the B<-CA> options). Normally all extensions are
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retained.
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=item B<-keyform PEM|DER>
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specifies the format (DER or PEM) of the private key file used in the
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B<-signkey> option.
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=item B<-days arg>
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specifies the number of days to make a certificate valid for. The default
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is 30 days.
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=item B<-x509toreq>
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converts a certificate into a certificate request. The B<-signkey> option
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is used to pass the required private key.
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=item B<-req>
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by default a certificate is expected on input. With this option a
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certificate request is expected instead.
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=item B<-set_serial n>
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specifies the serial number to use. This option can be used with either
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the B<-signkey> or B<-CA> options. If used in conjunction with the B<-CA>
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option the serial number file (as specified by the B<-CAserial> or
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B<-CAcreateserial> options) is not used.
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The serial number can be decimal or hex (if preceded by B<0x>). Negative
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serial numbers can also be specified but their use is not recommended.
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=item B<-CA filename>
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specifies the CA certificate to be used for signing. When this option is
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present B<x509> behaves like a "mini CA". The input file is signed by this
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CA using this option: that is its issuer name is set to the subject name
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of the CA and it is digitally signed using the CAs private key.
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This option is normally combined with the B<-req> option. Without the
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B<-req> option the input is a certificate which must be self signed.
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=item B<-CAkey filename>
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sets the CA private key to sign a certificate with. If this option is
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not specified then it is assumed that the CA private key is present in
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the CA certificate file.
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=item B<-CAserial filename>
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sets the CA serial number file to use.
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When the B<-CA> option is used to sign a certificate it uses a serial
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number specified in a file. This file consist of one line containing
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an even number of hex digits with the serial number to use. After each
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use the serial number is incremented and written out to the file again.
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The default filename consists of the CA certificate file base name with
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".srl" appended. For example if the CA certificate file is called
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"mycacert.pem" it expects to find a serial number file called "mycacert.srl".
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=item B<-CAcreateserial>
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with this option the CA serial number file is created if it does not exist:
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it will contain the serial number "02" and the certificate being signed will
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have the 1 as its serial number. Normally if the B<-CA> option is specified
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and the serial number file does not exist it is an error.
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=item B<-extfile filename>
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file containing certificate extensions to use. If not specified then
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no extensions are added to the certificate.
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=item B<-extensions section>
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the section to add certificate extensions from. If this option is not
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specified then the extensions should either be contained in the unnamed
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(default) section or the default section should contain a variable called
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"extensions" which contains the section to use. See the
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L<x509v3_config(5)|x509v3_config(5)> manual page for details of the
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extension section format.
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=back
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=head2 NAME OPTIONS
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The B<nameopt> command line switch determines how the subject and issuer
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names are displayed. If no B<nameopt> switch is present the default "oneline"
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format is used which is compatible with previous versions of OpenSSL.
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Each option is described in detail below, all options can be preceded by
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a B<-> to turn the option off. Only the first four will normally be used.
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=over 4
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=item B<compat>
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use the old format. This is equivalent to specifying no name options at all.
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=item B<RFC2253>
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displays names compatible with RFC2253 equivalent to B<esc_2253>, B<esc_ctrl>,
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B<esc_msb>, B<utf8>, B<dump_nostr>, B<dump_unknown>, B<dump_der>,
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B<sep_comma_plus>, B<dn_rev> and B<sname>.
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=item B<oneline>
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a oneline format which is more readable than RFC2253. It is equivalent to
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specifying the B<esc_2253>, B<esc_ctrl>, B<esc_msb>, B<utf8>, B<dump_nostr>,
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B<dump_der>, B<use_quote>, B<sep_comma_plus_space>, B<space_eq> and B<sname>
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options.
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=item B<multiline>
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a multiline format. It is equivalent B<esc_ctrl>, B<esc_msb>, B<sep_multiline>,
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B<space_eq>, B<lname> and B<align>.
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=item B<esc_2253>
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escape the "special" characters required by RFC2253 in a field That is
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B<,+"E<lt>E<gt>;>. Additionally B<#> is escaped at the beginning of a string
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and a space character at the beginning or end of a string.
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=item B<esc_ctrl>
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escape control characters. That is those with ASCII values less than
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0x20 (space) and the delete (0x7f) character. They are escaped using the
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RFC2253 \XX notation (where XX are two hex digits representing the
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character value).
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=item B<esc_msb>
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escape characters with the MSB set, that is with ASCII values larger than
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127.
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=item B<use_quote>
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escapes some characters by surrounding the whole string with B<"> characters,
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without the option all escaping is done with the B<\> character.
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=item B<utf8>
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convert all strings to UTF8 format first. This is required by RFC2253. If
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you are lucky enough to have a UTF8 compatible terminal then the use
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of this option (and B<not> setting B<esc_msb>) may result in the correct
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display of multibyte (international) characters. Is this option is not
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present then multibyte characters larger than 0xff will be represented
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using the format \UXXXX for 16 bits and \WXXXXXXXX for 32 bits.
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Also if this option is off any UTF8Strings will be converted to their
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character form first.
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=item B<no_type>
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this option does not attempt to interpret multibyte characters in any
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way. That is their content octets are merely dumped as though one octet
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represents each character. This is useful for diagnostic purposes but
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will result in rather odd looking output.
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=item B<show_type>
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show the type of the ASN1 character string. The type precedes the
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field contents. For example "BMPSTRING: Hello World".
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=item B<dump_der>
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when this option is set any fields that need to be hexdumped will
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be dumped using the DER encoding of the field. Otherwise just the
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content octets will be displayed. Both options use the RFC2253
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B<#XXXX...> format.
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=item B<dump_nostr>
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dump non character string types (for example OCTET STRING) if this
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option is not set then non character string types will be displayed
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as though each content octet represents a single character.
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=item B<dump_all>
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dump all fields. This option when used with B<dump_der> allows the
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DER encoding of the structure to be unambiguously determined.
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=item B<dump_unknown>
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dump any field whose OID is not recognised by OpenSSL.
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=item B<sep_comma_plus>, B<sep_comma_plus_space>, B<sep_semi_plus_space>,
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B<sep_multiline>
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these options determine the field separators. The first character is
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between RDNs and the second between multiple AVAs (multiple AVAs are
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very rare and their use is discouraged). The options ending in
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"space" additionally place a space after the separator to make it
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more readable. The B<sep_multiline> uses a linefeed character for
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the RDN separator and a spaced B<+> for the AVA separator. It also
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indents the fields by four characters.
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=item B<dn_rev>
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reverse the fields of the DN. This is required by RFC2253. As a side
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effect this also reverses the order of multiple AVAs but this is
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permissible.
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=item B<nofname>, B<sname>, B<lname>, B<oid>
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these options alter how the field name is displayed. B<nofname> does
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not display the field at all. B<sname> uses the "short name" form
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(CN for commonName for example). B<lname> uses the long form.
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B<oid> represents the OID in numerical form and is useful for
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diagnostic purpose.
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=item B<align>
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align field values for a more readable output. Only usable with
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B<sep_multiline>.
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=item B<space_eq>
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places spaces round the B<=> character which follows the field
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name.
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=back
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=head2 TEXT OPTIONS
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As well as customising the name output format, it is also possible to
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customise the actual fields printed using the B<certopt> options when
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the B<text> option is present. The default behaviour is to print all fields.
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=over 4
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=item B<compatible>
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use the old format. This is equivalent to specifying no output options at all.
|
|
|
|
=item B<no_header>
|
|
|
|
don't print header information: that is the lines saying "Certificate" and "Data".
|
|
|
|
=item B<no_version>
|
|
|
|
don't print out the version number.
|
|
|
|
=item B<no_serial>
|
|
|
|
don't print out the serial number.
|
|
|
|
=item B<no_signame>
|
|
|
|
don't print out the signature algorithm used.
|
|
|
|
=item B<no_validity>
|
|
|
|
don't print the validity, that is the B<notBefore> and B<notAfter> fields.
|
|
|
|
=item B<no_subject>
|
|
|
|
don't print out the subject name.
|
|
|
|
=item B<no_issuer>
|
|
|
|
don't print out the issuer name.
|
|
|
|
=item B<no_pubkey>
|
|
|
|
don't print out the public key.
|
|
|
|
=item B<no_sigdump>
|
|
|
|
don't give a hexadecimal dump of the certificate signature.
|
|
|
|
=item B<no_aux>
|
|
|
|
don't print out certificate trust information.
|
|
|
|
=item B<no_extensions>
|
|
|
|
don't print out any X509V3 extensions.
|
|
|
|
=item B<ext_default>
|
|
|
|
retain default extension behaviour: attempt to print out unsupported certificate extensions.
|
|
|
|
=item B<ext_error>
|
|
|
|
print an error message for unsupported certificate extensions.
|
|
|
|
=item B<ext_parse>
|
|
|
|
ASN1 parse unsupported extensions.
|
|
|
|
=item B<ext_dump>
|
|
|
|
hex dump unsupported extensions.
|
|
|
|
=item B<ca_default>
|
|
|
|
the value used by the B<ca> utility, equivalent to B<no_issuer>, B<no_pubkey>, B<no_header>,
|
|
B<no_version>, B<no_sigdump> and B<no_signame>.
|
|
|
|
=back
|
|
|
|
=head1 EXAMPLES
|
|
|
|
Note: in these examples the '\' means the example should be all on one
|
|
line.
|
|
|
|
Display the contents of a certificate:
|
|
|
|
openssl x509 -in cert.pem -noout -text
|
|
|
|
Display the certificate serial number:
|
|
|
|
openssl x509 -in cert.pem -noout -serial
|
|
|
|
Display the certificate subject name:
|
|
|
|
openssl x509 -in cert.pem -noout -subject
|
|
|
|
Display the certificate subject name in RFC2253 form:
|
|
|
|
openssl x509 -in cert.pem -noout -subject -nameopt RFC2253
|
|
|
|
Display the certificate subject name in oneline form on a terminal
|
|
supporting UTF8:
|
|
|
|
openssl x509 -in cert.pem -noout -subject -nameopt oneline,-esc_msb
|
|
|
|
Display the certificate MD5 fingerprint:
|
|
|
|
openssl x509 -in cert.pem -noout -fingerprint
|
|
|
|
Display the certificate SHA1 fingerprint:
|
|
|
|
openssl x509 -sha1 -in cert.pem -noout -fingerprint
|
|
|
|
Convert a certificate from PEM to DER format:
|
|
|
|
openssl x509 -in cert.pem -inform PEM -out cert.der -outform DER
|
|
|
|
Convert a certificate to a certificate request:
|
|
|
|
openssl x509 -x509toreq -in cert.pem -out req.pem -signkey key.pem
|
|
|
|
Convert a certificate request into a self signed certificate using
|
|
extensions for a CA:
|
|
|
|
openssl x509 -req -in careq.pem -extfile openssl.cnf -extensions v3_ca \
|
|
-signkey key.pem -out cacert.pem
|
|
|
|
Sign a certificate request using the CA certificate above and add user
|
|
certificate extensions:
|
|
|
|
openssl x509 -req -in req.pem -extfile openssl.cnf -extensions v3_usr \
|
|
-CA cacert.pem -CAkey key.pem -CAcreateserial
|
|
|
|
|
|
Set a certificate to be trusted for SSL client use and change set its alias to
|
|
"Steve's Class 1 CA"
|
|
|
|
openssl x509 -in cert.pem -addtrust clientAuth \
|
|
-setalias "Steve's Class 1 CA" -out trust.pem
|
|
|
|
=head1 NOTES
|
|
|
|
The PEM format uses the header and footer lines:
|
|
|
|
-----BEGIN CERTIFICATE-----
|
|
-----END CERTIFICATE-----
|
|
|
|
it will also handle files containing:
|
|
|
|
-----BEGIN X509 CERTIFICATE-----
|
|
-----END X509 CERTIFICATE-----
|
|
|
|
Trusted certificates have the lines
|
|
|
|
-----BEGIN TRUSTED CERTIFICATE-----
|
|
-----END TRUSTED CERTIFICATE-----
|
|
|
|
The conversion to UTF8 format used with the name options assumes that
|
|
T61Strings use the ISO8859-1 character set. This is wrong but Netscape
|
|
and MSIE do this as do many certificates. So although this is incorrect
|
|
it is more likely to display the majority of certificates correctly.
|
|
|
|
The B<-fingerprint> option takes the digest of the DER encoded certificate.
|
|
This is commonly called a "fingerprint". Because of the nature of message
|
|
digests the fingerprint of a certificate is unique to that certificate and
|
|
two certificates with the same fingerprint can be considered to be the same.
|
|
|
|
The Netscape fingerprint uses MD5 whereas MSIE uses SHA1.
|
|
|
|
The B<-email> option searches the subject name and the subject alternative
|
|
name extension. Only unique email addresses will be printed out: it will
|
|
not print the same address more than once.
|
|
|
|
=head1 CERTIFICATE EXTENSIONS
|
|
|
|
The B<-purpose> option checks the certificate extensions and determines
|
|
what the certificate can be used for. The actual checks done are rather
|
|
complex and include various hacks and workarounds to handle broken
|
|
certificates and software.
|
|
|
|
The same code is used when verifying untrusted certificates in chains
|
|
so this section is useful if a chain is rejected by the verify code.
|
|
|
|
The basicConstraints extension CA flag is used to determine whether the
|
|
certificate can be used as a CA. If the CA flag is true then it is a CA,
|
|
if the CA flag is false then it is not a CA. B<All> CAs should have the
|
|
CA flag set to true.
|
|
|
|
If the basicConstraints extension is absent then the certificate is
|
|
considered to be a "possible CA" other extensions are checked according
|
|
to the intended use of the certificate. A warning is given in this case
|
|
because the certificate should really not be regarded as a CA: however
|
|
it is allowed to be a CA to work around some broken software.
|
|
|
|
If the certificate is a V1 certificate (and thus has no extensions) and
|
|
it is self signed it is also assumed to be a CA but a warning is again
|
|
given: this is to work around the problem of Verisign roots which are V1
|
|
self signed certificates.
|
|
|
|
If the keyUsage extension is present then additional restraints are
|
|
made on the uses of the certificate. A CA certificate B<must> have the
|
|
keyCertSign bit set if the keyUsage extension is present.
|
|
|
|
The extended key usage extension places additional restrictions on the
|
|
certificate uses. If this extension is present (whether critical or not)
|
|
the key can only be used for the purposes specified.
|
|
|
|
A complete description of each test is given below. The comments about
|
|
basicConstraints and keyUsage and V1 certificates above apply to B<all>
|
|
CA certificates.
|
|
|
|
|
|
=over 4
|
|
|
|
=item B<SSL Client>
|
|
|
|
The extended key usage extension must be absent or include the "web client
|
|
authentication" OID. keyUsage must be absent or it must have the
|
|
digitalSignature bit set. Netscape certificate type must be absent or it must
|
|
have the SSL client bit set.
|
|
|
|
=item B<SSL Client CA>
|
|
|
|
The extended key usage extension must be absent or include the "web client
|
|
authentication" OID. Netscape certificate type must be absent or it must have
|
|
the SSL CA bit set: this is used as a work around if the basicConstraints
|
|
extension is absent.
|
|
|
|
=item B<SSL Server>
|
|
|
|
The extended key usage extension must be absent or include the "web server
|
|
authentication" and/or one of the SGC OIDs. keyUsage must be absent or it
|
|
must have the digitalSignature, the keyEncipherment set or both bits set.
|
|
Netscape certificate type must be absent or have the SSL server bit set.
|
|
|
|
=item B<SSL Server CA>
|
|
|
|
The extended key usage extension must be absent or include the "web server
|
|
authentication" and/or one of the SGC OIDs. Netscape certificate type must
|
|
be absent or the SSL CA bit must be set: this is used as a work around if the
|
|
basicConstraints extension is absent.
|
|
|
|
=item B<Netscape SSL Server>
|
|
|
|
For Netscape SSL clients to connect to an SSL server it must have the
|
|
keyEncipherment bit set if the keyUsage extension is present. This isn't
|
|
always valid because some cipher suites use the key for digital signing.
|
|
Otherwise it is the same as a normal SSL server.
|
|
|
|
=item B<Common S/MIME Client Tests>
|
|
|
|
The extended key usage extension must be absent or include the "email
|
|
protection" OID. Netscape certificate type must be absent or should have the
|
|
S/MIME bit set. If the S/MIME bit is not set in netscape certificate type
|
|
then the SSL client bit is tolerated as an alternative but a warning is shown:
|
|
this is because some Verisign certificates don't set the S/MIME bit.
|
|
|
|
=item B<S/MIME Signing>
|
|
|
|
In addition to the common S/MIME client tests the digitalSignature bit must
|
|
be set if the keyUsage extension is present.
|
|
|
|
=item B<S/MIME Encryption>
|
|
|
|
In addition to the common S/MIME tests the keyEncipherment bit must be set
|
|
if the keyUsage extension is present.
|
|
|
|
=item B<S/MIME CA>
|
|
|
|
The extended key usage extension must be absent or include the "email
|
|
protection" OID. Netscape certificate type must be absent or must have the
|
|
S/MIME CA bit set: this is used as a work around if the basicConstraints
|
|
extension is absent.
|
|
|
|
=item B<CRL Signing>
|
|
|
|
The keyUsage extension must be absent or it must have the CRL signing bit
|
|
set.
|
|
|
|
=item B<CRL Signing CA>
|
|
|
|
The normal CA tests apply. Except in this case the basicConstraints extension
|
|
must be present.
|
|
|
|
=back
|
|
|
|
=head1 BUGS
|
|
|
|
Extensions in certificates are not transferred to certificate requests and
|
|
vice versa.
|
|
|
|
It is possible to produce invalid certificates or requests by specifying the
|
|
wrong private key or using inconsistent options in some cases: these should
|
|
be checked.
|
|
|
|
There should be options to explicitly set such things as start and end
|
|
dates rather than an offset from the current time.
|
|
|
|
The code to implement the verify behaviour described in the B<TRUST SETTINGS>
|
|
is currently being developed. It thus describes the intended behaviour rather
|
|
than the current behaviour. It is hoped that it will represent reality in
|
|
OpenSSL 0.9.5 and later.
|
|
|
|
=head1 SEE ALSO
|
|
|
|
L<req(1)|req(1)>, L<ca(1)|ca(1)>, L<genrsa(1)|genrsa(1)>,
|
|
L<gendsa(1)|gendsa(1)>, L<verify(1)|verify(1)>,
|
|
L<x509v3_config(5)|x509v3_config(5)>
|
|
|
|
=head1 HISTORY
|
|
|
|
Before OpenSSL 0.9.8, the default digest for RSA keys was MD5.
|
|
|
|
The hash algorithm used in the B<-subject_hash> and B<-issuer_hash> options
|
|
before OpenSSL 1.0.0 was based on the deprecated MD5 algorithm and the encoding
|
|
of the distinguished name. In OpenSSL 1.0.0 and later it is based on a
|
|
canonical version of the DN using SHA1. This means that any directories using
|
|
the old form must have their links rebuilt using B<c_rehash> or similar.
|
|
|
|
=cut
|
|
|