X509 1 2008-05-09 0.9.9-dev OpenSSL

NAME

x509 - Certificate display and signing utility

LIBRARY

libcrypto, -lcrypto

SYNOPSIS

ooppeennssssll xx550099 [--iinnffoorrmm DDEERR||PPEEMM||NNEETT] [--oouuttffoorrmm DDEERR||PPEEMM||NNEETT] [--kkeeyyffoorrmm DDEERR||PPEEMM] [--CCAAffoorrmm DDEERR||PPEEMM] [--CCAAkkeeyyffoorrmm DDEERR||PPEEMM] [--iinn ffiilleennaammee] [--oouutt ffiilleennaammee] [--sseerriiaall] [--hhaasshh] [--ssuubbjjeecctt__hhaasshh] [--iissssuueerr__hhaasshh] [--ssuubbjjeecctt] [--iissssuueerr] [--nnaammeeoopptt ooppttiioonn] [--eemmaaiill] [--ssttaarrttddaattee] [--eennddddaattee] [--ppuurrppoossee] [--ddaatteess] [--mmoodduulluuss] [--ffiinnggeerrpprriinntt] [--aalliiaass] [--nnoooouutt] [--ttrruussttoouutt] [--ccllrrttrruusstt] [--ccllrrrreejjeecctt] [--aaddddttrruusstt aarrgg] [--aaddddrreejjeecctt aarrgg] [--sseettaalliiaass aarrgg] [--ddaayyss aarrgg] [--sseett__sseerriiaall nn] [--ssiiggnnkkeeyy ffiilleennaammee] [--xx550099ttoorreeqq] [--rreeqq] [--CCAA ffiilleennaammee] [--CCAAkkeeyy ffiilleennaammee] [--CCAAccrreeaatteesseerriiaall] [--CCAAsseerriiaall ffiilleennaammee] [--tteexxtt] [--CC] [--mmdd22||--mmdd55||--sshhaa11||--mmddcc22] [--ccllrreexxtt] [--eexxttffiillee ffiilleennaammee] [--eexxtteennssiioonnss sseeccttiioonn] [--eennggiinnee iidd]

DESCRIPTION

The xx550099 command is a multi purpose certificate utility. It can be used to display certificate information, convert certificates to various forms, sign certificate requests like a "mini CA" or edit certificate trust settings.

Since there are a large number of options they will split up into various sections.

OPTIONS


IINNPPUUTT,, OOUUTTPPUUTT AANNDD GGEENNEERRAALL PPUURRPPOOSSEE OOPPTTIIOONNSS

--iinnffoorrmm DDEERR||PPEEMM||NNEETT This specifies the input format normally the command will expect an X509
certificate but this can change if other options such as --rreeqq are present. The DER format is the DER encoding of the certificate and PEM is the base64 encoding of the DER encoding with header and footer lines added. The NET option is an obscure Netscape server format that is now obsolete.
--oouuttffoorrmm DDEERR||PPEEMM||NNEETT This specifies the output format, the options have the same meaning as the
--iinnffoorrmm option.
--iinn ffiilleennaammee This specifies the input filename to read a certificate from or standard input
if this option is not specified.
--oouutt ffiilleennaammee This specifies the output filename to write to or standard output by
default.
--mmdd22||--mmdd55||--sshhaa11||--mmddcc22 the digest to use. This affects any signing or display option that uses a message
digest, such as the --ffiinnggeerrpprriinntt, --ssiiggnnkkeeyy and --CCAA options. If not specified then SHA1 is used. If the key being used to sign with is a DSA key then this option has no effect: SHA1 is always used with DSA keys.
--eennggiinnee iidd specifying an engine (by it's unique iidd string) will cause rreeqq
to attempt to obtain a functional reference to the specified engine, thus initialising it if needed. The engine will then be set as the default for all available algorithms.

DDIISSPPLLAAYY OOPPTTIIOONNSS

Note: the --aalliiaass and --ppuurrppoossee options are also display options but are described in the TTRRUUSSTT SSEETTTTIINNGGSS section.

--tteexxtt prints out the certificate in text form. Full details are output including the
public key, signature algorithms, issuer and subject names, serial number any extensions present and any trust settings.
--cceerrttoopptt ooppttiioonn customise the output format used with --tteexxtt. The ooppttiioonn argument can be
a single option or multiple options separated by commas. The --cceerrttoopptt switch may be also be used more than once to set multiple options. See the TTEEXXTT OOPPTTIIOONNSS section for more information.
--nnoooouutt this option prevents output of the encoded version of the request.
--mmoodduulluuss this option prints out the value of the modulus of the public key
contained in the certificate.
--sseerriiaall outputs the certificate serial number.
--ssuubbjjeecctt__hhaasshh outputs the "hash" of the certificate subject name. This is used in OpenSSL to
form an index to allow certificates in a directory to be looked up by subject name.
--iissssuueerr__hhaasshh outputs the "hash" of the certificate issuer name.
--hhaasshh synonym for "-hash" for backward compatibility reasons.
--ssuubbjjeecctt outputs the subject name.
--iissssuueerr outputs the issuer name.
--nnaammeeoopptt ooppttiioonn option which determines how the subject or issuer names are displayed. The
ooppttiioonn argument can be a single option or multiple options separated by commas. Alternatively the --nnaammeeoopptt switch may be used more than once to set multiple options. See the NNAAMMEE OOPPTTIIOONNSS section for more information.
--eemmaaiill outputs the email address(es) if any.
--ssttaarrttddaattee prints out the start date of the certificate, that is the notBefore date.
--eennddddaattee prints out the expiry date of the certificate, that is the notAfter date.
--ddaatteess prints out the start and expiry dates of a certificate.
--ffiinnggeerrpprriinntt prints out the digest of the DER encoded version of the whole certificate
(see digest options).
--CC this outputs the certificate in the form of a C source file.

TTRRUUSSTT SSEETTTTIINNGGSS

Please note these options are currently experimental and may well change.

A ttrruusstteedd cceerrttiiffiiccaattee is an ordinary certificate which has several additional pieces of information attached to it such as the permitted and prohibited uses of the certificate and an "alias".

Normally when a certificate is being verified at least one certificate must be "trusted". By default a trusted certificate must be stored locally and must be a root CA: any certificate chain ending in this CA is then usable for any purpose.

Trust settings currently are only used with a root CA. They allow a finer control over the purposes the root CA can be used for. For example a CA may be trusted for SSL client but not SSL server use.

See the description of the vveerriiffyy utility for more information on the meaning of trust settings.

Future versions of OpenSSL will recognize trust settings on any certificate: not just root CAs.

--ttrruussttoouutt this causes xx550099 to output a ttrruusstteedd certificate. An ordinary
or trusted certificate can be input but by default an ordinary certificate is output and any trust settings are discarded. With the --ttrruussttoouutt option a trusted certificate is output. A trusted certificate is automatically output if any trust settings are modified.
--sseettaalliiaass aarrgg sets the alias of the certificate. This will allow the certificate
to be referred to using a nickname for example "Steve's Certificate".
--aalliiaass outputs the certificate alias, if any.
--ccllrrttrruusstt clears all the permitted or trusted uses of the certificate.
--ccllrrrreejjeecctt clears all the prohibited or rejected uses of the certificate.
--aaddddttrruusstt aarrgg adds a trusted certificate use. Any object name can be used here
but currently only cclliieennttAAuutthh (SSL client use), sseerrvveerrAAuutthh (SSL server use) and eemmaaiillPPrrootteeccttiioonn (S/MIME email) are used. Other OpenSSL applications may define additional uses.
--aaddddrreejjeecctt aarrgg adds a prohibited use. It accepts the same values as the --aaddddttrruusstt
option.
--ppuurrppoossee this option performs tests on the certificate extensions and outputs
the results. For a more complete description see the CCEERRTTIIFFIICCAATTEE EEXXTTEENNSSIIOONNSS section.

SSIIGGNNIINNGG OOPPTTIIOONNSS

The xx550099 utility can be used to sign certificates and requests: it can thus behave like a "mini CA".

--ssiiggnnkkeeyy ffiilleennaammee this option causes the input file to be self signed using the supplied
private key.

If the input file is a certificate it sets the issuer name to the subject name (i.e. makes it self signed) changes the public key to the supplied value and changes the start and end dates. The start date is set to the current time and the end date is set to a value determined by the --ddaayyss option. Any certificate extensions are retained unless the --ccllrreexxtt option is supplied.

If the input is a certificate request then a self signed certificate is created using the supplied private key using the subject name in the request.
--ccllrreexxtt delete any extensions from a certificate. This option is used when a
certificate is being created from another certificate (for example with the --ssiiggnnkkeeyy or the --CCAA options). Normally all extensions are retained.
--kkeeyyffoorrmm PPEEMM||DDEERR specifies the format (DER or PEM) of the private key file used in the
--ssiiggnnkkeeyy option.
--ddaayyss aarrgg specifies the number of days to make a certificate valid for. The default
is 30 days.
--xx550099ttoorreeqq converts a certificate into a certificate request. The --ssiiggnnkkeeyy option
is used to pass the required private key.
--rreeqq by default a certificate is expected on input. With this option a
certificate request is expected instead.
--sseett__sseerriiaall nn specifies the serial number to use. This option can be used with either
the --ssiiggnnkkeeyy or --CCAA options. If used in conjunction with the --CCAA option the serial number file (as specified by the --CCAAsseerriiaall or --CCAAccrreeaatteesseerriiaall options) is not used.

The serial number can be decimal or hex (if preceded by 00xx). Negative serial numbers can also be specified but their use is not recommended.
--CCAA ffiilleennaammee specifies the CA certificate to be used for signing. When this option is
present xx550099 behaves like a "mini CA". The input file is signed by this CA using this option: that is its issuer name is set to the subject name of the CA and it is digitally signed using the CAs private key.

This option is normally combined with the --rreeqq option. Without the --rreeqq option the input is a certificate which must be self signed.
--CCAAkkeeyy ffiilleennaammee sets the CA private key to sign a certificate with. If this option is
not specified then it is assumed that the CA private key is present in the CA certificate file.
--CCAAsseerriiaall ffiilleennaammee sets the CA serial number file to use.


When the --CCAA option is used to sign a certificate it uses a serial number specified in a file. This file consist of one line containing an even number of hex digits with the serial number to use. After each use the serial number is incremented and written out to the file again.

The default filename consists of the CA certificate file base name with ".srl" appended. For example if the CA certificate file is called "mycacert.pem" it expects to find a serial number file called "mycacert.srl".
--CCAAccrreeaatteesseerriiaall with this option the CA serial number file is created if it does not exist:
it will contain the serial number "02" and the certificate being signed will have the 1 as its serial number. Normally if the --CCAA option is specified and the serial number file does not exist it is an error.
--eexxttffiillee ffiilleennaammee file containing certificate extensions to use. If not specified then
no extensions are added to the certificate.
--eexxtteennssiioonnss sseeccttiioonn the section to add certificate extensions from. If this option is not
specified then the extensions should either be contained in the unnamed (default) section or the default section should contain a variable called "extensions" which contains the section to use. See the _x_5_0_9_v_3___c_o_n_f_i_g(5) manual page for details of the extension section format.

NNAAMMEE OOPPTTIIOONNSS

The nnaammeeoopptt command line switch determines how the subject and issuer names are displayed. If no nnaammeeoopptt switch is present the default "oneline" format is used which is compatible with previous versions of OpenSSL. Each option is described in detail below, all options can be preceded by a -- to turn the option off. Only the first four will normally be used.

ccoommppaatt use the old format. This is equivalent to specifying no name options at all.
RRFFCC22225533 displays names compatible with RFC2253 equivalent to eesscc__22225533, eesscc__ccttrrll,
eesscc__mmssbb, uuttff88, dduummpp__nnoossttrr, dduummpp__uunnkknnoowwnn, dduummpp__ddeerr, sseepp__ccoommmmaa__pplluuss, ddnn__rreevv and ssnnaammee.
oonneelliinnee a oneline format which is more readable than RFC2253. It is equivalent to
specifying the eesscc__22225533, eesscc__ccttrrll, eesscc__mmssbb, uuttff88, dduummpp__nnoossttrr, dduummpp__ddeerr, uussee__qquuoottee, sseepp__ccoommmmaa__pplluuss__ssppaaccee, ssppaaccee__eeqq and ssnnaammee options.
mmuullttiilliinnee a multiline format. It is equivalent eesscc__ccttrrll, eesscc__mmssbb, sseepp__mmuullttiilliinnee,
ssppaaccee__eeqq, llnnaammee and aalliiggnn.
eesscc__22225533 escape the "special" characters required by RFC2253 in a field That is
,,++""<<>>;;. Additionally ## is escaped at the beginning of a string and a space character at the beginning or end of a string.
eesscc__ccttrrll escape control characters. That is those with ASCII values less than
0x20 (space) and the delete (0x7f) character. They are escaped using the RFC2253 \XX notation (where XX are two hex digits representing the character value).
eesscc__mmssbb escape characters with the MSB set, that is with ASCII values larger than
127.
uussee__qquuoottee escapes some characters by surrounding the whole string with "" characters,
without the option all escaping is done with the \\ character.
uuttff88 convert all strings to UTF8 format first. This is required by RFC2253. If
you are lucky enough to have a UTF8 compatible terminal then the use of this option (and nnoott setting eesscc__mmssbb) may result in the correct display of multibyte (international) characters. Is this option is not present then multibyte characters larger than 0xff will be represented using the format \UXXXX for 16 bits and \WXXXXXXXX for 32 bits. Also if this option is off any UTF8Strings will be converted to their character form first.
nnoo__ttyyppee this option does not attempt to interpret multibyte characters in any
way. That is their content octets are merely dumped as though one octet represents each character. This is useful for diagnostic purposes but will result in rather odd looking output.
sshhooww__ttyyppee show the type of the ASN1 character string. The type precedes the
field contents. For example "BMPSTRING: Hello World".
dduummpp__ddeerr when this option is set any fields that need to be hexdumped will
be dumped using the DER encoding of the field. Otherwise just the content octets will be displayed. Both options use the RFC2253 ##XXXXXXXX...... format.
dduummpp__nnoossttrr dump non character string types (for example OCTET STRING) if this
option is not set then non character string types will be displayed as though each content octet represents a single character.
dduummpp__aallll dump all fields. This option when used with dduummpp__ddeerr allows the
DER encoding of the structure to be unambiguously determined.
dduummpp__uunnkknnoowwnn dump any field whose OID is not recognised by OpenSSL.
sseepp__ccoommmmaa__pplluuss, sseepp__ccoommmmaa__pplluuss__ssppaaccee, sseepp__sseemmii__pplluuss__ssppaaccee, sseepp__mmuullttiilliinnee these options determine the field separators. The first character is
between RDNs and the second between multiple AVAs (multiple AVAs are very rare and their use is discouraged). The options ending in "space" additionally place a space after the separator to make it more readable. The sseepp__mmuullttiilliinnee uses a linefeed character for the RDN separator and a spaced ++ for the AVA separator. It also indents the fields by four characters.
ddnn__rreevv reverse the fields of the DN. This is required by RFC2253. As a side
effect this also reverses the order of multiple AVAs but this is permissible.
nnooffnnaammee, ssnnaammee, llnnaammee, ooiidd these options alter how the field name is displayed. nnooffnnaammee does
not display the field at all. ssnnaammee uses the "short name" form (CN for commonName for example). llnnaammee uses the long form. ooiidd represents the OID in numerical form and is useful for diagnostic purpose.
aalliiggnn align field values for a more readable output. Only usable with
sseepp__mmuullttiilliinnee.
ssppaaccee__eeqq places spaces round the == character which follows the field
name.

TTEEXXTT OOPPTTIIOONNSS

As well as customising the name output format, it is also possible to customise the actual fields printed using the cceerrttoopptt options when the tteexxtt option is present. The default behaviour is to print all fields.

ccoommppaattiibbllee use the old format. This is equivalent to specifying no output options at all.
nnoo__hheeaaddeerr don't print header information: that is the lines saying "Certificate" and "Data".
nnoo__vveerrssiioonn don't print out the version number.
nnoo__sseerriiaall don't print out the serial number.
nnoo__ssiiggnnaammee don't print out the signature algorithm used.
nnoo__vvaalliiddiittyy don't print the validity, that is the nnoottBBeeffoorree and nnoottAAfftteerr fields.
nnoo__ssuubbjjeecctt don't print out the subject name.
nnoo__iissssuueerr don't print out the issuer name.
nnoo__ppuubbkkeeyy don't print out the public key.
nnoo__ssiiggdduummpp don't give a hexadecimal dump of the certificate signature.
nnoo__aauuxx don't print out certificate trust information.
nnoo__eexxtteennssiioonnss don't print out any X509V3 extensions.
eexxtt__ddeeffaauulltt retain default extension behaviour: attempt to print out unsupported certificate extensions.
eexxtt__eerrrroorr print an error message for unsupported certificate extensions.
eexxtt__ppaarrssee ASN1 parse unsupported extensions.
eexxtt__dduummpp hex dump unsupported extensions.
ccaa__ddeeffaauulltt the value used by the ccaa utility, equivalent to nnoo__iissssuueerr, nnoo__ppuubbkkeeyy, nnoo__hheeaaddeerr,
nnoo__vveerrssiioonn, nnoo__ssiiggdduummpp and nnoo__ssiiggnnaammee.

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

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 --ffiinnggeerrpprriinntt 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 --eemmaaiill 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.

CERTIFICATE EXTENSIONS

The --ppuurrppoossee 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. AAllll 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 mmuusstt 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 aallll CA certificates.

SSSSLL CClliieenntt 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.
SSSSLL CClliieenntt CCAA 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.
SSSSLL SSeerrvveerr 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.
SSSSLL SSeerrvveerr CCAA 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.
NNeettssccaappee SSSSLL SSeerrvveerr 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.
CCoommmmoonn SS//MMIIMMEE CClliieenntt TTeessttss 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.
SS//MMIIMMEE SSiiggnniinngg In addition to the common S/MIME client tests the digitalSignature bit must
be set if the keyUsage extension is present.
SS//MMIIMMEE EEnnccrryyppttiioonn In addition to the common S/MIME tests the keyEncipherment bit must be set
if the keyUsage extension is present.
SS//MMIIMMEE CCAA 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.
CCRRLL SSiiggnniinngg The keyUsage extension must be absent or it must have the CRL signing bit
set.
CCRRLL SSiiggnniinngg CCAA The normal CA tests apply. Except in this case the basicConstraints extension
must be present.

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 TTRRUUSSTT SSEETTTTIINNGGSS 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.

SEE ALSO

_o_p_e_n_s_s_l___r_e_q(1), _o_p_e_n_s_s_l___c_a(1), _o_p_e_n_s_s_l___g_e_n_r_s_a(1), _o_p_e_n_s_s_l___g_e_n_d_s_a(1), _o_p_e_n_s_s_l___v_e_r_i_f_y(1), _x_5_0_9_v_3___c_o_n_f_i_g(5)

HISTORY

Before OpenSSL 0.9.8, the default digest for RSA keys was MD5.