Standard preamble:
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.... Set up some character translations and predefined strings. \*(-- will
give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
double quote, and \*(R" will give a right double quote. \*(C+ will
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\}
Escape single quotes in literal strings from groff's Unicode transform.
If the F register is >0, we'll generate index entries on stderr for
titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
entries marked with X<> in POD. Of course, you'll have to process the
output yourself in some meaningful fashion.
Avoid warning from groff about undefined register 'F'.
.. .nr rF 0 . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF
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 "SSL_SET1_HOST 3"
way too many mistakes in technical documents.
\fBSSL_set1_host() sets the expected \s-1DNS\s0 hostname to name clearing any previously specified hostname or names. If name is \s-1NULL,\s0 or the empty string the list of hostnames is cleared, and name checks are not performed on the peer certificate. When a nonempty \fBname is specified, certificate verification automatically checks the peer hostname via X509_check_host\|(3) with flags as specified via SSL_set_hostflags(). Clients that enable \s-1DANE TLSA\s0 authentication via SSL_dane_enable\|(3) should leave it to that function to set the primary reference identifier of the peer, and should not call \fBSSL_set1_host().
\fBSSL_add1_host() adds name as an additional reference identifier that can match the peer's certificate. Any previous names set via \fBSSL_set1_host() or SSL_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. This function is required for \s-1DANE TLSA\s0 in the presence of service name indirection via \s-1CNAME, MX\s0 or \s-1SRV\s0 records as specified in \s-1RFC7671, RFC7672\s0 or \s-1RFC7673.\s0
\fBSSL_set_hostflags() sets the flags that will be passed to \fBX509_check_host\|(3) when name checks are applicable, by default the flags value is 0. See X509_check_host\|(3) for the list of available flags and their meaning.
\fBSSL_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, the name matched in the peer certificate may be a wildcard name. When one of the reference identifiers configured via SSL_set1_host() or \fBSSL_add1_host() starts with \*(L".\*(R", which indicates a parent domain prefix rather than a fixed name, the matched peer name may be a sub-domain of the reference identifier. The returned string is allocated by the library and is no longer valid once the associated ssl handle is cleared or freed, or a renegotiation takes place. Applications must not free the return value.
\s-1SSL\s0 clients are advised to use these functions in preference to explicitly calling X509_check_host\|(3). Hostname checks may be out of scope with the \s-1RFC7671 DANE-EE\s0\|(3) certificate usage, and the internal check will be suppressed as appropriate when \s-1DANE\s0 is enabled.
\fBSSL_get0_peername() returns \s-1NULL\s0 if peername verification is not applicable (as with \s-1RFC7671 DANE-EE\s0\|(3)), or no trusted peername was matched. Otherwise, it returns the matched peername. To determine whether verification succeeded call SSL_get_verify_result\|(3).
.Vb 5 SSL_set_hostflags(ssl, X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS); if (!SSL_set1_host(ssl, "smtp.example.com")) /* error */ if (!SSL_add1_host(ssl, "example.com")) /* error */ \& /* XXX: Perform SSL_connect() handshake and handle errors here */ \& if (SSL_get_verify_result(ssl) == X509_V_OK) { const char *peername = SSL_get0_peername(ssl); \& if (peername != NULL) /* Name checks were in scope and matched the peername */ } .Ve
Licensed under the OpenSSL license (the \*(L"License\*(R"). You may not use this file except in compliance with the License. You can obtain a copy in the file \s-1LICENSE\s0 in the source distribution or at <https://www.openssl.org/source/license.html>.