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give a nicer C++. Capital omega is used to do unbreakable dashes and
therefore won't be available. \*(C` and \*(C' expand to `' in nroff,
nothing in troff, for use with C<>.
.tr \(*W- . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\}
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Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
Fear. Run. Save yourself. No user-serviceable parts.
. \" fudge factors for nroff and troff . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] .\} . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents . \" corrections for vroff . \" for low resolution devices (crt and lpr) \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} ========================================================================
Title "X509_VERIFY_PARAM_set_flags 3"
way too many mistakes in technical documents.
The X509_VERIFY_PARAM_set_flags() function sets the flags in param by oring it with flags. See the \s-1VERIFICATION FLAGS\s0 section for a complete description of values the flags parameter can take.
\fIX509_VERIFY_PARAM_get_flags() returns the flags in param.
\fIX509_VERIFY_PARAM_clear_flags() clears the flags flags in param.
\fIX509_VERIFY_PARAM_set_purpose() sets the verification purpose in param to purpose. This determines the acceptable purpose of the certificate chain, for example \s-1SSL\s0 client or \s-1SSL\s0 server.
\fIX509_VERIFY_PARAM_set_trust() sets the trust setting in param to \fBtrust.
\fIX509_VERIFY_PARAM_set_time() sets the verification time in param to \fBt. Normally the current time is used.
\fIX509_VERIFY_PARAM_add0_policy() enables policy checking (it is disabled by default) and adds policy to the acceptable policy set.
\fIX509_VERIFY_PARAM_set1_policies() enables policy checking (it is disabled by default) and sets the acceptable policy set to policies. Any existing policy set is cleared. The policies parameter can be \s-1NULL\s0 to clear an existing policy set.
\fIX509_VERIFY_PARAM_set_depth() sets the maximum verification depth to depth. That is the maximum number of untrusted \s-1CA\s0 certificates that can appear in a chain.
\fIX509_VERIFY_PARAM_set1_host() sets the expected \s-1DNS\s0 hostname to \fBname clearing any previously specified host name or names. If \fBname is \s-1NULL,\s0 or empty the list of hostnames is cleared, and name checks are not performed on the peer certificate. If name is NUL-terminated, namelen may be zero, otherwise namelen must be set to the length of name. When a hostname is specified, certificate verification automatically invokes X509_check_host\|(3) with flags equal to the flags argument given to \fB\f(BIX509_VERIFY_PARAM_set_hostflags() (default zero). Applications are strongly advised to use this interface in preference to explicitly calling X509_check_host\|(3), hostname checks are out of scope with the \s-1DANE-EE\s0\|(3) certificate usage, and the internal check will be suppressed as appropriate when \s-1DANE\s0 support is added to OpenSSL.
\fIX509_VERIFY_PARAM_add1_host() adds name as an additional reference identifer that can match the peer's certificate. Any previous names set via X509_VERIFY_PARAM_set1_host() or X509_VERIFY_PARAM_add1_host() are retained, no change is made if name is \s-1NULL\s0 or empty. When multiple names are configured, the peer is considered verified when any name matches.
\fIX509_VERIFY_PARAM_get0_peername() returns the \s-1DNS\s0 hostname or subject CommonName from the peer certificate that matched one of the reference identifiers. When wildcard matching is not disabled, or when a reference identifier specifies a parent domain (starts with \*(L".\*(R") rather than a hostname, the peer name may be a wildcard name or a sub-domain of the reference identifier respectively. The return string is allocated by the library and is no longer valid once the associated param argument is freed. Applications must not free the return value.
\fIX509_VERIFY_PARAM_set1_email() sets the expected \s-1RFC822\s0 email address to \fBemail. If email is NUL-terminated, emaillen may be zero, otherwise \fBemaillen must be set to the length of email. When an email address is specified, certificate verification automatically invokes \fIX509_check_email\|(3).
\fIX509_VERIFY_PARAM_set1_ip() sets the expected \s-1IP\s0 address to ip. The ip argument is in binary format, in network byte-order and \fBiplen must be set to 4 for IPv4 and 16 for IPv6. When an \s-1IP\s0 address is specified, certificate verification automatically invokes \fIX509_check_ip\|(3).
\fIX509_VERIFY_PARAM_set1_ip_asc() sets the expected \s-1IP\s0 address to \fBipasc. The ipasc argument is a NUL-terminal \s-1ASCII\s0 string: dotted decimal quad for IPv4 and colon-separated hexadecimal for IPv6. The condensed \*(L"::\*(R" notation is supported for IPv6 addresses.
\fIX509_VERIFY_PARAM_get_flags() returns the current verification flags.
\fIX509_VERIFY_PARAM_set_time() and X509_VERIFY_PARAM_set_depth() do not return values.
\fIX509_VERIFY_PARAM_get_depth() returns the current verification depth.
\fBX509_V_FLAG_CRL_CHECK enables \s-1CRL\s0 checking for the certificate chain leaf certificate. An error occurs if a suitable \s-1CRL\s0 cannot be found.
\fBX509_V_FLAG_CRL_CHECK_ALL enables \s-1CRL\s0 checking for the entire certificate chain.
\fBX509_V_FLAG_IGNORE_CRITICAL disabled critical extension checking. By default any unhandled critical extensions in certificates or (if checked) CRLs results in a fatal error. If this flag is set unhandled critical extensions are ignored. \s-1WARNING\s0 setting this option for anything other than debugging purposes can be a security risk. Finer control over which extensions are supported can be performed in the verification callback.
THe X509_V_FLAG_X509_STRICT flag disables workarounds for some broken certificates and makes the verification strictly apply X509 rules.
\fBX509_V_FLAG_ALLOW_PROXY_CERTS enables proxy certificate verification.
\fBX509_V_FLAG_POLICY_CHECK enables certificate policy checking, by default no policy checking is peformed. Additional information is sent to the verification callback relating to policy checking.
\fBX509_V_FLAG_EXPLICIT_POLICY, X509_V_FLAG_INHIBIT_ANY and \fBX509_V_FLAG_INHIBIT_MAP set the require explicit policy, inhibit any policy and inhibit policy mapping flags respectively as defined in \fB\s-1RFC3280\s0. Policy checking is automatically enabled if any of these flags are set.
If X509_V_FLAG_NOTIFY_POLICY is set and the policy checking is successful a special status code is set to the verification callback. This permits it to examine the valid policy tree and perform additional checks or simply log it for debugging purposes.
By default some additional features such as indirect CRLs and CRLs signed by different keys are disabled. If X509_V_FLAG_EXTENDED_CRL_SUPPORT is set they are enabled.
If X509_V_FLAG_USE_DELTAS ise set delta CRLs (if present) are used to determine certificate status. If not set deltas are ignored.
\fBX509_V_FLAG_CHECK_SS_SIGNATURE enables checking of the root \s-1CA\s0 self signed cerificate signature. By default this check is disabled because it doesn't add any additional security but in some cases applications might want to check the signature anyway. A side effect of not checking the root \s-1CA\s0 signature is that disabled or unsupported message digests on the root \s-1CA\s0 are not treated as fatal errors.
The X509_V_FLAG_CB_ISSUER_CHECK flag enables debugging of certificate issuer checks. It is not needed unless you are logging certificate verification. If this flag is set then additional status codes will be sent to the verification callback and it must be prepared to handle such cases without assuming they are hard errors.
The X509_V_FLAG_NO_ALT_CHAINS flag suppresses checking for alternative chains. By default, when building a certificate chain, if the first certificate chain found is not trusted, then OpenSSL will continue to check to see if an alternative chain can be found that is trusted. With this flag set the behaviour will match that of OpenSSL versions prior to 1.0.2b.
If CRLs checking is enable CRLs are expected to be available in the corresponding X509_STORE structure. No attempt is made to download CRLs from the \s-1CRL\s0 distribution points extension.
.Vb 5 X509_VERIFY_PARAM *param; param = X509_VERIFY_PARAM_new(); X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_CRL_CHECK); SSL_CTX_set1_param(ctx, param); X509_VERIFY_PARAM_free(param); .Ve