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Diffstat (limited to 'secure/lib/libcrypto/man/man3/X509_check_host.3')
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diff --git a/secure/lib/libcrypto/man/man3/X509_check_host.3 b/secure/lib/libcrypto/man/man3/X509_check_host.3 new file mode 100644 index 000000000000..15dcedbdf41d --- /dev/null +++ b/secure/lib/libcrypto/man/man3/X509_check_host.3 @@ -0,0 +1,214 @@ +.\" -*- mode: troff; coding: utf-8 -*- +.\" Automatically generated by Pod::Man 5.0102 (Pod::Simple 3.45) +.\" +.\" Standard preamble: +.\" ======================================================================== +.de Sp \" Vertical space (when we can't use .PP) +.if t .sp .5v +.if n .sp +.. +.de Vb \" Begin verbatim text +.ft CW +.nf +.ne \\$1 +.. +.de Ve \" End verbatim text +.ft R +.fi +.. +.\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. +.ie n \{\ +. ds C` "" +. ds C' "" +'br\} +.el\{\ +. ds C` +. ds C' +'br\} +.\" +.\" Escape single quotes in literal strings from groff's Unicode transform. +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" +.\" 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'. +.de IX +.. +.nr rF 0 +.if \n(.g .if rF .nr rF 1 +.if (\n(rF:(\n(.g==0)) \{\ +. if \nF \{\ +. de IX +. tm Index:\\$1\t\\n%\t"\\$2" +.. +. if !\nF==2 \{\ +. nr % 0 +. nr F 2 +. \} +. \} +.\} +.rr rF +.\" ======================================================================== +.\" +.IX Title "X509_CHECK_HOST 3ossl" +.TH X509_CHECK_HOST 3ossl 2025-09-30 3.5.4 OpenSSL +.\" For nroff, turn off justification. Always turn off hyphenation; it makes +.\" way too many mistakes in technical documents. +.if n .ad l +.nh +.SH NAME +X509_check_host, X509_check_email, X509_check_ip, X509_check_ip_asc \- X.509 certificate matching +.SH SYNOPSIS +.IX Header "SYNOPSIS" +.Vb 1 +\& #include <openssl/x509v3.h> +\& +\& int X509_check_host(X509 *, const char *name, size_t namelen, +\& unsigned int flags, char **peername); +\& int X509_check_email(X509 *, const char *address, size_t addresslen, +\& unsigned int flags); +\& int X509_check_ip(X509 *, const unsigned char *address, size_t addresslen, +\& unsigned int flags); +\& int X509_check_ip_asc(X509 *, const char *address, unsigned int flags); +.Ve +.SH DESCRIPTION +.IX Header "DESCRIPTION" +The certificate matching functions are used to check whether a +certificate matches a given hostname, email address, or IP address. +The validity of the certificate and its trust level has to be checked by +other means. +.PP +\&\fBX509_check_host()\fR checks if the certificate Subject Alternative +Name (SAN) or Subject CommonName (CN) matches the specified hostname, +which must be encoded in the preferred name syntax described +in section 3.5 of RFC 1034. By default, wildcards are supported +and they match only in the left-most label; but they may match +part of that label with an explicit prefix or suffix. For example, +by default, the host \fBname\fR "www.example.com" would match a +certificate with a SAN or CN value of "*.example.com", "w*.example.com" +or "*w.example.com". +.PP +Per section 6.4.2 of RFC 6125, \fBname\fR values representing international +domain names must be given in A\-label form. The \fBnamelen\fR argument +must be the number of characters in the name string or zero in which +case the length is calculated with strlen(\fBname\fR). When \fBname\fR starts +with a dot (e.g. ".example.com"), it will be matched by a certificate +valid for any sub-domain of \fBname\fR, (see also +\&\fBX509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS\fR below). +.PP +When the certificate is matched, and \fBpeername\fR is not NULL, a +pointer to a copy of the matching SAN or CN from the peer certificate +is stored at the address passed in \fBpeername\fR. The application +is responsible for freeing the peername via \fBOPENSSL_free()\fR when it +is no longer needed. +.PP +\&\fBX509_check_email()\fR checks if the certificate matches the specified +email \fBaddress\fR. The mailbox syntax of RFC 822 is supported, +comments are not allowed, and no attempt is made to normalize quoted +characters. The mailbox syntax of RFC 6531 is supported for +SmtpUTF8Mailbox address in subjectAltName according to RFC 8398, +with similar limitations as for RFC 822 syntax, and no attempt +is made to convert from A\-label to U\-label before comparison. +The \fBaddresslen\fR argument must be the number of +characters in the address string or zero in which case the length +is calculated with strlen(\fBaddress\fR). +.PP +\&\fBX509_check_ip()\fR checks if the certificate matches a specified IPv4 or +IPv6 address. The \fBaddress\fR array is in binary format, in network +byte order. The length is either 4 (IPv4) or 16 (IPv6). Only +explicitly marked addresses in the certificates are considered; IP +addresses stored in DNS names and Common Names are ignored. There are +currently no \fBflags\fR that would affect the behavior of this call. +.PP +\&\fBX509_check_ip_asc()\fR is similar, except that the NUL-terminated +string \fBaddress\fR is first converted to the internal representation. +.PP +The \fBflags\fR argument is usually 0. It can be the bitwise OR of the +flags: +.IP \fBX509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT\fR, 4 +.IX Item "X509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT," +.PD 0 +.IP \fBX509_CHECK_FLAG_NEVER_CHECK_SUBJECT\fR, 4 +.IX Item "X509_CHECK_FLAG_NEVER_CHECK_SUBJECT," +.IP \fBX509_CHECK_FLAG_NO_WILDCARDS\fR, 4 +.IX Item "X509_CHECK_FLAG_NO_WILDCARDS," +.IP \fBX509_CHECK_FLAG_NO_PARTIAL_WILDCARDS\fR, 4 +.IX Item "X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS," +.IP \fBX509_CHECK_FLAG_MULTI_LABEL_WILDCARDS\fR. 4 +.IX Item "X509_CHECK_FLAG_MULTI_LABEL_WILDCARDS." +.IP \fBX509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS\fR. 4 +.IX Item "X509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS." +.PD +.PP +The \fBX509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT\fR flag causes the function +to consider the subject DN even if the certificate contains at least +one subject alternative name of the right type (DNS name or email +address as appropriate); the default is to ignore the subject DN +when at least one corresponding subject alternative names is present. +.PP +The \fBX509_CHECK_FLAG_NEVER_CHECK_SUBJECT\fR flag causes the function to never +consider the subject DN even if the certificate contains no subject alternative +names of the right type (DNS name or email address as appropriate); the default +is to use the subject DN when no corresponding subject alternative names are +present. +If both \fBX509_CHECK_FLAG_ALWAYS_CHECK_SUBJECT\fR and +\&\fBX509_CHECK_FLAG_NEVER_CHECK_SUBJECT\fR are specified, the latter takes +precedence and the subject DN is not checked for matching names. +.PP +If set, \fBX509_CHECK_FLAG_NO_WILDCARDS\fR disables wildcard +expansion; this only applies to \fBX509_check_host\fR. +.PP +If set, \fBX509_CHECK_FLAG_NO_PARTIAL_WILDCARDS\fR suppresses support +for "*" as wildcard pattern in labels that have a prefix or suffix, +such as: "www*" or "*www"; this only applies to \fBX509_check_host\fR. +.PP +If set, \fBX509_CHECK_FLAG_MULTI_LABEL_WILDCARDS\fR allows a "*" that +constitutes the complete label of a DNS name (e.g. "*.example.com") +to match more than one label in \fBname\fR; this flag only applies +to \fBX509_check_host\fR. +.PP +If set, \fBX509_CHECK_FLAG_SINGLE_LABEL_SUBDOMAINS\fR restricts \fBname\fR +values which start with ".", that would otherwise match any sub-domain +in the peer certificate, to only match direct child sub-domains. +Thus, for instance, with this flag set a \fBname\fR of ".example.com" +would match a peer certificate with a DNS name of "www.example.com", +but would not match a peer certificate with a DNS name of +"www.sub.example.com"; this flag only applies to \fBX509_check_host\fR. +.SH "RETURN VALUES" +.IX Header "RETURN VALUES" +The functions return 1 for a successful match, 0 for a failed match +and \-1 for an internal error: typically a memory allocation failure +or an ASN.1 decoding error. +.PP +All functions can also return \-2 if the input is malformed. For example, +\&\fBX509_check_host()\fR returns \-2 if the provided \fBname\fR contains embedded +NULs. +.SH NOTES +.IX Header "NOTES" +Applications are encouraged to use \fBX509_VERIFY_PARAM_set1_host()\fR +rather than explicitly calling \fBX509_check_host\fR\|(3). Hostname +checks may be out of scope with the \fBDANE\-EE\fR\|(3) certificate usage, +and the internal checks will be suppressed as appropriate when +DANE support is enabled. +.SH "SEE ALSO" +.IX Header "SEE ALSO" +\&\fBSSL_get_verify_result\fR\|(3), +\&\fBX509_VERIFY_PARAM_set1_host\fR\|(3), +\&\fBX509_VERIFY_PARAM_add1_host\fR\|(3), +\&\fBX509_VERIFY_PARAM_set1_email\fR\|(3), +\&\fBX509_VERIFY_PARAM_set1_ip\fR\|(3) +.SH HISTORY +.IX Header "HISTORY" +These functions were added in OpenSSL 1.0.2. +.SH COPYRIGHT +.IX Header "COPYRIGHT" +Copyright 2012\-2022 The OpenSSL Project Authors. All Rights Reserved. +.PP +Licensed under the Apache License 2.0 (the "License"). You may not use +this file except in compliance with the License. You can obtain a copy +in the file LICENSE in the source distribution or at +<https://www.openssl.org/source/license.html>. |