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Diffstat (limited to 'secure/lib/libcrypto/man/man3/SSL_CONF_cmd.3')
| -rw-r--r-- | secure/lib/libcrypto/man/man3/SSL_CONF_cmd.3 | 609 |
1 files changed, 339 insertions, 270 deletions
diff --git a/secure/lib/libcrypto/man/man3/SSL_CONF_cmd.3 b/secure/lib/libcrypto/man/man3/SSL_CONF_cmd.3 index 1624309e7b42..527aa9d88dc8 100644 --- a/secure/lib/libcrypto/man/man3/SSL_CONF_cmd.3 +++ b/secure/lib/libcrypto/man/man3/SSL_CONF_cmd.3 @@ -1,4 +1,5 @@ -.\" Automatically generated by Pod::Man 4.14 (Pod::Simple 3.42) +.\" -*- mode: troff; coding: utf-8 -*- +.\" Automatically generated by Pod::Man 5.0102 (Pod::Simple 3.45) .\" .\" Standard preamble: .\" ======================================================================== @@ -15,29 +16,12 @@ .ft R .fi .. -.\" 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 C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p' +.\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. .ie n \{\ -. 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\} .el\{\ -. ds -- \|\(em\| -. ds PI \(*p -. ds L" `` -. ds R" '' . ds C` . ds C' 'br\} @@ -68,78 +52,18 @@ . \} .\} .rr rF -.\" Fear. Run. Save yourself. No user-serviceable parts. -. \" fudge factors for nroff and troff -.if n \{\ -. ds #H 0 -. ds #V .8m -. ds #F .3m -. ds #[ \f1 -. ds #] \fP -.\} -.if t \{\ -. ds #H ((1u-(\\\\n(.fu%2u))*.13m) -. ds #V .6m -. ds #F 0 -. ds #[ \& -. ds #] \& -.\} -. \" simple accents for nroff and troff -.if n \{\ -. ds ' \& -. ds ` \& -. ds ^ \& -. ds , \& -. ds ~ ~ -. ds / -.\} -.if t \{\ -. 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 -.ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V' -.ds 8 \h'\*(#H'\(*b\h'-\*(#H' -.ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#] -.ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H' -.ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u' -.ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#] -.ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#] -.ds ae a\h'-(\w'a'u*4/10)'e -.ds Ae A\h'-(\w'A'u*4/10)'E -. \" corrections for vroff -.if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u' -.if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u' -. \" for low resolution devices (crt and lpr) -.if \n(.H>23 .if \n(.V>19 \ -\{\ -. 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 -.\} -.rm #[ #] #H #V #F C .\" ======================================================================== .\" .IX Title "SSL_CONF_CMD 3ossl" -.TH SSL_CONF_CMD 3ossl "2023-09-19" "3.0.11" "OpenSSL" +.TH SSL_CONF_CMD 3ossl 2025-07-01 3.5.1 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" +.SH NAME SSL_CONF_cmd_value_type, SSL_CONF_cmd \- send configuration command -.SH "SYNOPSIS" +.SH SYNOPSIS .IX Header "SYNOPSIS" .Vb 1 \& #include <openssl/ssl.h> @@ -147,77 +71,85 @@ SSL_CONF_cmd \- send configuration command \& int SSL_CONF_cmd(SSL_CONF_CTX *ctx, const char *option, const char *value); \& int SSL_CONF_cmd_value_type(SSL_CONF_CTX *ctx, const char *option); .Ve -.SH "DESCRIPTION" +.SH DESCRIPTION .IX Header "DESCRIPTION" The function \fBSSL_CONF_cmd()\fR performs configuration operation \fBoption\fR with optional parameter \fBvalue\fR on \fBctx\fR. Its purpose is to simplify application -configuration of \fB\s-1SSL_CTX\s0\fR or \fB\s-1SSL\s0\fR structures by providing a common +configuration of \fBSSL_CTX\fR or \fBSSL\fR structures by providing a common framework for command line options or configuration files. .PP \&\fBSSL_CONF_cmd_value_type()\fR returns the type of value that \fBoption\fR refers to. .SH "SUPPORTED COMMAND LINE COMMANDS" .IX Header "SUPPORTED COMMAND LINE COMMANDS" Currently supported \fBoption\fR names for command lines (i.e. when the -flag \fB\s-1SSL_CONF_FLAG_CMDLINE\s0\fR is set) are listed below. Note: all \fBoption\fR +flag \fBSSL_CONF_FLAG_CMDLINE\fR is set) are listed below. Note: all \fBoption\fR names are case sensitive. Unless otherwise stated commands can be used by both clients and servers and the \fBvalue\fR parameter is not used. The default prefix for command line commands is \fB\-\fR and that is reflected below. -.IP "\fB\-bugs\fR" 4 +.IP \fB\-bugs\fR 4 .IX Item "-bugs" -Various bug workarounds are set, same as setting \fB\s-1SSL_OP_ALL\s0\fR. -.IP "\fB\-no_comp\fR" 4 +Various bug workarounds are set, same as setting \fBSSL_OP_ALL\fR. +.IP \fB\-no_comp\fR 4 .IX Item "-no_comp" -Disables support for \s-1SSL/TLS\s0 compression, same as setting -\&\fB\s-1SSL_OP_NO_COMPRESSION\s0\fR. +Disables support for SSL/TLS compression, same as setting +\&\fBSSL_OP_NO_COMPRESSION\fR. As of OpenSSL 1.1.0, compression is off by default. -.IP "\fB\-comp\fR" 4 +.IP \fB\-comp\fR 4 .IX Item "-comp" -Enables support for \s-1SSL/TLS\s0 compression, same as clearing -\&\fB\s-1SSL_OP_NO_COMPRESSION\s0\fR. +Enables support for SSL/TLS compression, same as clearing +\&\fBSSL_OP_NO_COMPRESSION\fR. This command was introduced in OpenSSL 1.1.0. -As of OpenSSL 1.1.0, compression is off by default. -.IP "\fB\-no_ticket\fR" 4 +As of OpenSSL 1.1.0, compression is off by default. TLS compression can only be +used in security level 1 or lower. From OpenSSL 3.2.0 and above the default +security level is 2, so this option will have no effect without also changing +the security level. See \fBSSL_CTX_set_security_level\fR\|(3). +.IP \fB\-no_ticket\fR 4 .IX Item "-no_ticket" -Disables support for session tickets, same as setting \fB\s-1SSL_OP_NO_TICKET\s0\fR. -.IP "\fB\-serverpref\fR" 4 +Disables support for session tickets, same as setting \fBSSL_OP_NO_TICKET\fR. +.IP \fB\-serverpref\fR 4 .IX Item "-serverpref" Use server and not client preference order when determining which cipher suite, signature algorithm or elliptic curve to use for an incoming connection. -Equivalent to \fB\s-1SSL_OP_CIPHER_SERVER_PREFERENCE\s0\fR. Only used by servers. -.IP "\fB\-client_renegotiation\fR" 4 +Equivalent to \fBSSL_OP_CIPHER_SERVER_PREFERENCE\fR. Only used by servers. +.IP \fB\-client_renegotiation\fR 4 .IX Item "-client_renegotiation" Allows servers to accept client-initiated renegotiation. Equivalent to -setting \fB\s-1SSL_OP_ALLOW_CLIENT_RENEGOTIATION\s0\fR. +setting \fBSSL_OP_ALLOW_CLIENT_RENEGOTIATION\fR. Only used by servers. -.IP "\fB\-legacy_renegotiation\fR" 4 +.IP \fB\-legacy_renegotiation\fR 4 .IX Item "-legacy_renegotiation" Permits the use of unsafe legacy renegotiation. Equivalent to setting -\&\fB\s-1SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION\s0\fR. -.IP "\fB\-no_renegotiation\fR" 4 +\&\fBSSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION\fR. +.IP \fB\-no_renegotiation\fR 4 .IX Item "-no_renegotiation" -Disables all attempts at renegotiation in TLSv1.2 and earlier, same as setting -\&\fB\s-1SSL_OP_NO_RENEGOTIATION\s0\fR. -.IP "\fB\-no_resumption_on_reneg\fR" 4 +Disables all attempts at renegotiation in (D)TLSv1.2 and earlier, same as setting +\&\fBSSL_OP_NO_RENEGOTIATION\fR. +.IP \fB\-no_resumption_on_reneg\fR 4 .IX Item "-no_resumption_on_reneg" -Sets \fB\s-1SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION\s0\fR. Only used by servers. +Sets \fBSSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION\fR. Only used by servers. .IP "\fB\-legacy_server_connect\fR, \fB\-no_legacy_server_connect\fR" 4 .IX Item "-legacy_server_connect, -no_legacy_server_connect" Permits or prohibits the use of unsafe legacy renegotiation for OpenSSL -clients only. Equivalent to setting or clearing \fB\s-1SSL_OP_LEGACY_SERVER_CONNECT\s0\fR. -.IP "\fB\-prioritize_chacha\fR" 4 +clients only. Equivalent to setting or clearing \fBSSL_OP_LEGACY_SERVER_CONNECT\fR. +.IP \fB\-prioritize_chacha\fR 4 .IX Item "-prioritize_chacha" Prioritize ChaCha ciphers when the client has a ChaCha20 cipher at the top of -its preference list. This usually indicates a client without \s-1AES\s0 hardware -acceleration (e.g. mobile) is in use. Equivalent to \fB\s-1SSL_OP_PRIORITIZE_CHACHA\s0\fR. +its preference list. This usually indicates a client without AES hardware +acceleration (e.g. mobile) is in use. Equivalent to \fBSSL_OP_PRIORITIZE_CHACHA\fR. Only used by servers. Requires \fB\-serverpref\fR. -.IP "\fB\-allow_no_dhe_kex\fR" 4 +.IP \fB\-allow_no_dhe_kex\fR 4 .IX Item "-allow_no_dhe_kex" In TLSv1.3 allow a non\-(ec)dhe based key exchange mode on resumption. This means that there will be no forward secrecy for the resumed session. -.IP "\fB\-strict\fR" 4 +.IP \fB\-prefer_no_dhe_kex\fR 4 +.IX Item "-prefer_no_dhe_kex" +In TLSv1.3, on resumption let the server prefer a non\-(ec)dhe based key +exchange mode over an (ec)dhe based one. Requires \fB\-allow_no_dhe_kex\fR. +Equivalent to \fBSSL_OP_PREFER_NO_DHE_KEX\fR. Only used by servers. +.IP \fB\-strict\fR 4 .IX Item "-strict" Enables strict mode protocol handling. Equivalent to setting -\&\fB\s-1SSL_CERT_FLAG_TLS_STRICT\s0\fR. +\&\fBSSL_CERT_FLAG_TLS_STRICT\fR. .IP "\fB\-sigalgs\fR \fIalgs\fR" 4 .IX Item "-sigalgs algs" This sets the supported signature algorithms for TLSv1.2 and TLSv1.3. @@ -227,18 +159,23 @@ algorithms to support. .Sp The \fBalgs\fR argument should be a colon separated list of signature algorithms in order of decreasing preference of the form \fBalgorithm+hash\fR -or \fBsignature_scheme\fR. \fBalgorithm\fR is one of \fB\s-1RSA\s0\fR, \fB\s-1DSA\s0\fR or \fB\s-1ECDSA\s0\fR and -\&\fBhash\fR is a supported algorithm \s-1OID\s0 short name such as \fB\s-1SHA1\s0\fR, \fB\s-1SHA224\s0\fR, -\&\fB\s-1SHA256\s0\fR, \fB\s-1SHA384\s0\fR of \fB\s-1SHA512\s0\fR. Note: algorithm and hash names are case -sensitive. \fBsignature_scheme\fR is one of the signature schemes defined in -TLSv1.3, specified using the \s-1IETF\s0 name, e.g., \fBecdsa_secp256r1_sha256\fR, -\&\fBed25519\fR, or \fBrsa_pss_pss_sha256\fR. -.Sp -If this option is not set then all signature algorithms supported by the -OpenSSL library are permissible. +or \fBsignature_scheme\fR. For the default providers shipped with OpenSSL, +\&\fBalgorithm\fR is one of \fBRSA\fR, \fBDSA\fR or \fBECDSA\fR and +\&\fBhash\fR is a supported algorithm OID short name such as \fBSHA1\fR, \fBSHA224\fR, +\&\fBSHA256\fR, \fBSHA384\fR or \fBSHA512\fR. +\&\fBsignature_scheme\fR is one of the signature schemes defined +in TLSv1.3, specified using the IETF name, e.g., \fBecdsa_secp256r1_sha256\fR, +\&\fBed25519\fR, or \fBrsa_pss_pss_sha256\fR. Additional providers may make available +further algorithms via the TLS-SIGALG capability. +Signature scheme names and public key algorithm names (but not the hash names) +in the \fBalgorithm+hash\fR form are case-insensitive. +See \fBprovider\-base\fR\|(7). +.Sp +If this option is not set then all signature algorithms supported by all +activated providers are permissible. .Sp Note: algorithms which specify a PKCS#1 v1.5 signature scheme (either by -using \fB\s-1RSA\s0\fR as the \fBalgorithm\fR or by using one of the \fBrsa_pkcs1_*\fR +using \fBRSA\fR as the \fBalgorithm\fR or by using one of the \fBrsa_pkcs1_*\fR identifiers) are ignored in TLSv1.3 and will not be negotiated. .IP "\fB\-client_sigalgs\fR \fIalgs\fR" 4 .IX Item "-client_sigalgs algs" @@ -256,35 +193,84 @@ value set for \fB\-sigalgs\fR will be used instead. This sets the supported groups. For clients, the groups are sent using the supported groups extension. For servers, it is used to determine which group to use. This setting affects groups used for signatures (in TLSv1.2 -and earlier) and key exchange. The first group listed will also be used -for the \fBkey_share\fR sent by a client in a TLSv1.3 \fBClientHello\fR. -.Sp -The \fBgroups\fR argument is a colon separated list of groups. The group can -be either the \fB\s-1NIST\s0\fR name (e.g. \fBP\-256\fR), some other commonly used name -where applicable (e.g. \fBX25519\fR, \fBffdhe2048\fR) or an OpenSSL \s-1OID\s0 name -(e.g. \fBprime256v1\fR). Group names are case sensitive. The list should be -in order of preference with the most preferred group first. -.Sp -Currently supported groups for \fBTLSv1.3\fR are \fBP\-256\fR, \fBP\-384\fR, \fBP\-521\fR, -\&\fBX25519\fR, \fBX448\fR, \fBffdhe2048\fR, \fBffdhe3072\fR, \fBffdhe4096\fR, \fBffdhe6144\fR, -\&\fBffdhe8192\fR. +and earlier) and key exchange. +.Sp +In its simplest form the \fIgroups\fR argument is a colon separated list of +groups. The preferred names are those listed in the IANA +TLS Supported Groups <https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-8> +registry. +.Sp +For some groups, OpenSSL supports additional aliases. +Such an alias could be a \fBNIST\fR name (e.g. \fBP\-256\fR), an OpenSSL OID name +(e.g. \fBprime256v1\fR), or some other commonly used name. +Group names are case-insensitive in OpenSSL 3.5 and later. +The list should be in order of preference with the most preferred group first. +.Sp +The first group listed will also be used for the \fBkey_share\fR sent by a client +in a TLSv1.3 \fBClientHello\fR. +.Sp +The commands below list the IANA names for TLS 1.2 and TLS 1.3, +respectively: +.Sp +.Vb 2 +\& $ openssl list \-tls1_2 \-tls\-groups +\& $ openssl list \-tls1_3 \-tls\-groups +.Ve +.Sp +The recommended groups (in order of decreasing performance) for TLS 1.3 are presently: +.Sp +\&\fBx25519\fR, +\&\fBsecp256r1\fR, +\&\fBx448\fR, +and +\&\fBsecp384r1\fR. +.Sp +The stronger security margins of the last two, come at a significant +performance penalty. +.Sp +An enriched alternative syntax, that enables clients to send multiple keyshares +and allows servers to prioritise some groups over others, is described in +\&\fBSSL_CTX_set1_groups_list\fR\|(3). +Since TLS 1.2 has neither keyshares nor a hello retry mechanism, with TLS 1.2 +the enriched syntax is ultimately equivalent to just a simple ordered list of +groups, as with the simple form above. .IP "\fB\-curves\fR \fIgroups\fR" 4 .IX Item "-curves groups" This is a synonym for the \fB\-groups\fR command. .IP "\fB\-named_curve\fR \fIcurve\fR" 4 .IX Item "-named_curve curve" -This sets the temporary curve used for ephemeral \s-1ECDH\s0 modes. Only used -by servers. +This sets the temporary curve used for ephemeral ECDH modes. +This is only applicable in TLS 1.0 and 1.1, and should not be used with later +protocol versions. .Sp -The \fBgroups\fR argument is a curve name or the special value \fBauto\fR which +The \fIcurve\fR argument is a curve name or the special value \fBauto\fR which picks an appropriate curve based on client and server preferences. The -curve can be either the \fB\s-1NIST\s0\fR name (e.g. \fBP\-256\fR) or an OpenSSL \s-1OID\s0 name -(e.g. \fBprime256v1\fR). Curve names are case sensitive. +curve can be either the \fBNIST\fR name (e.g. \fBP\-256\fR) or an OpenSSL OID name +(e.g. \fBprime256v1\fR). +Even with TLS 1.0 and 1.1, the default value of \f(CW\*(C`auto\*(C'\fR is strongly recommended +over choosing a specific curve. +Curve names are case-insensitive in OpenSSL 3.5 and later. +.IP \fB\-tx_cert_comp\fR 4 +.IX Item "-tx_cert_comp" +Enables support for sending TLSv1.3 compressed certificates. +.IP \fB\-no_tx_cert_comp\fR 4 +.IX Item "-no_tx_cert_comp" +Disables support for sending TLSv1.3 compressed certificates. +.IP \fB\-rx_cert_comp\fR 4 +.IX Item "-rx_cert_comp" +Enables support for receiving TLSv1.3 compressed certificates. +.IP \fB\-no_rx_cert_comp\fR 4 +.IX Item "-no_rx_cert_comp" +Disables support for receiving TLSv1.3 compressed certificates. +.IP \fB\-comp\fR 4 +.IX Item "-comp" +.PD 0 .IP "\fB\-cipher\fR \fIciphers\fR" 4 .IX Item "-cipher ciphers" +.PD Sets the TLSv1.2 and below ciphersuite list to \fBciphers\fR. This list will be combined with any configured TLSv1.3 ciphersuites. Note: syntax checking -of \fBciphers\fR is currently not performed unless a \fB\s-1SSL\s0\fR or \fB\s-1SSL_CTX\s0\fR +of \fBciphers\fR is currently not performed unless a \fBSSL\fR or \fBSSL_CTX\fR structure is associated with \fBctx\fR. .IP "\fB\-ciphersuites\fR \fI1.3ciphers\fR" 4 .IX Item "-ciphersuites 1.3ciphers" @@ -296,26 +282,32 @@ See \fBopenssl\-ciphers\fR\|(1) for more information. .IX Item "-min_protocol minprot, -max_protocol maxprot" Sets the minimum and maximum supported protocol. Currently supported protocol values are \fBSSLv3\fR, \fBTLSv1\fR, \fBTLSv1.1\fR, -\&\fBTLSv1.2\fR, \fBTLSv1.3\fR for \s-1TLS\s0; \fBDTLSv1\fR, \fBDTLSv1.2\fR for \s-1DTLS,\s0 and \fBNone\fR +\&\fBTLSv1.2\fR, \fBTLSv1.3\fR for TLS; \fBDTLSv1\fR, \fBDTLSv1.2\fR for DTLS, and \fBNone\fR for no limit. If either the lower or upper bound is not specified then only the other bound applies, if specified. -If your application supports both \s-1TLS\s0 and \s-1DTLS\s0 you can specify any of these -options twice, once with a bound for \s-1TLS\s0 and again with an appropriate bound -for \s-1DTLS.\s0 +If your application supports both TLS and DTLS you can specify any of these +options twice, once with a bound for TLS and again with an appropriate bound +for DTLS. To restrict the supported protocol versions use these commands rather than the deprecated alternative commands below. .IP "\fB\-record_padding\fR \fIpadding\fR" 4 .IX Item "-record_padding padding" -Attempts to pad TLSv1.3 records so that they are a multiple of \fBpadding\fR -in length on send. A \fBpadding\fR of 0 or 1 turns off padding. Otherwise, -the \fBpadding\fR must be >1 or <=16384. -.IP "\fB\-debug_broken_protocol\fR" 4 +Controls use of TLSv1.3 record layer padding. \fBpadding\fR is a string of the +form "number[,number]" where the (required) first number is the padding block +size (in octets) for application data, and the optional second number is the +padding block size for handshake and alert messages. If the optional second +number is omitted, the same padding will be applied to all messages. +.Sp +Padding attempts to pad TLSv1.3 records so that they are a multiple of the set +length on send. A value of 0 or 1 turns off padding as relevant. Otherwise, the +values must be >1 or <=16384. +.IP \fB\-debug_broken_protocol\fR 4 .IX Item "-debug_broken_protocol" Ignored. -.IP "\fB\-no_middlebox\fR" 4 +.IP \fB\-no_middlebox\fR 4 .IX Item "-no_middlebox" -Turn off \*(L"middlebox compatibility\*(R", as described below. +Turn off "middlebox compatibility", as described below. .SS "Additional Options" .IX Subsection "Additional Options" The following options are accepted by \fBSSL_CONF_cmd()\fR, but are not @@ -323,19 +315,19 @@ processed by the OpenSSL commands. .IP "\fB\-cert\fR \fIfile\fR" 4 .IX Item "-cert file" Attempts to use \fBfile\fR as the certificate for the appropriate context. It -currently uses \fBSSL_CTX_use_certificate_chain_file()\fR if an \fB\s-1SSL_CTX\s0\fR -structure is set or \fBSSL_use_certificate_file()\fR with filetype \s-1PEM\s0 if an -\&\fB\s-1SSL\s0\fR structure is set. This option is only supported if certificate +currently uses \fBSSL_CTX_use_certificate_chain_file()\fR if an \fBSSL_CTX\fR +structure is set or \fBSSL_use_certificate_file()\fR with filetype PEM if an +\&\fBSSL\fR structure is set. This option is only supported if certificate operations are permitted. .IP "\fB\-key\fR \fIfile\fR" 4 .IX Item "-key file" Attempts to use \fBfile\fR as the private key for the appropriate context. This option is only supported if certificate operations are permitted. Note: if no \fB\-key\fR option is set then a private key is not loaded unless the -flag \fB\s-1SSL_CONF_FLAG_REQUIRE_PRIVATE\s0\fR is set. +flag \fBSSL_CONF_FLAG_REQUIRE_PRIVATE\fR is set. .IP "\fB\-dhparam\fR \fIfile\fR" 4 .IX Item "-dhparam file" -Attempts to use \fBfile\fR as the set of temporary \s-1DH\s0 parameters for +Attempts to use \fBfile\fR as the set of temporary DH parameters for the appropriate context. This option is only supported if certificate operations are permitted. .IP "\fB\-no_ssl3\fR, \fB\-no_tls1\fR, \fB\-no_tls1_1\fR, \fB\-no_tls1_2\fR, \fB\-no_tls1_3\fR" 4 @@ -355,68 +347,74 @@ time. Anti-Replay is on by default unless overridden by a configuration file and is only used by servers. Anti-replay measures are required for compliance with the TLSv1.3 specification. Some applications may be able to mitigate the replay risks in other ways and in such cases the built-in OpenSSL functionality is not -required. Switching off anti-replay is equivalent to \fB\s-1SSL_OP_NO_ANTI_REPLAY\s0\fR. +required. Switching off anti-replay is equivalent to \fBSSL_OP_NO_ANTI_REPLAY\fR. .SH "SUPPORTED CONFIGURATION FILE COMMANDS" .IX Header "SUPPORTED CONFIGURATION FILE COMMANDS" Currently supported \fBoption\fR names for configuration files (i.e., when the -flag \fB\s-1SSL_CONF_FLAG_FILE\s0\fR is set) are listed below. All configuration file +flag \fBSSL_CONF_FLAG_FILE\fR is set) are listed below. All configuration file \&\fBoption\fR names are case insensitive so \fBsignaturealgorithms\fR is recognised as well as \fBSignatureAlgorithms\fR. Unless otherwise stated the \fBvalue\fR names are also case insensitive. .PP Note: the command prefix (if set) alters the recognised \fBoption\fR values. -.IP "\fBCipherString\fR" 4 +.IP \fBCipherString\fR 4 .IX Item "CipherString" Sets the ciphersuite list for TLSv1.2 and below to \fBvalue\fR. This list will be combined with any configured TLSv1.3 ciphersuites. Note: syntax -checking of \fBvalue\fR is currently not performed unless an \fB\s-1SSL\s0\fR or \fB\s-1SSL_CTX\s0\fR +checking of \fBvalue\fR is currently not performed unless an \fBSSL\fR or \fBSSL_CTX\fR structure is associated with \fBctx\fR. -.IP "\fBCiphersuites\fR" 4 +.IP \fBCiphersuites\fR 4 .IX Item "Ciphersuites" Sets the available ciphersuites for TLSv1.3 to \fBvalue\fR. This is a colon-separated list of TLSv1.3 ciphersuite names in order of preference. This list will be combined any configured TLSv1.2 and below ciphersuites. See \fBopenssl\-ciphers\fR\|(1) for more information. -.IP "\fBCertificate\fR" 4 +.IP \fBCertificate\fR 4 .IX Item "Certificate" Attempts to use the file \fBvalue\fR as the certificate for the appropriate -context. It currently uses \fBSSL_CTX_use_certificate_chain_file()\fR if an \fB\s-1SSL_CTX\s0\fR -structure is set or \fBSSL_use_certificate_file()\fR with filetype \s-1PEM\s0 if an \fB\s-1SSL\s0\fR +context. It currently uses \fBSSL_CTX_use_certificate_chain_file()\fR if an \fBSSL_CTX\fR +structure is set or \fBSSL_use_certificate_file()\fR with filetype PEM if an \fBSSL\fR structure is set. This option is only supported if certificate operations are permitted. -.IP "\fBPrivateKey\fR" 4 +.IP \fBPrivateKey\fR 4 .IX Item "PrivateKey" Attempts to use the file \fBvalue\fR as the private key for the appropriate context. This option is only supported if certificate operations are permitted. Note: if no \fBPrivateKey\fR option is set then a private key is -not loaded unless the \fB\s-1SSL_CONF_FLAG_REQUIRE_PRIVATE\s0\fR is set. +not loaded unless the \fBSSL_CONF_FLAG_REQUIRE_PRIVATE\fR is set. .IP "\fBChainCAFile\fR, \fBChainCAPath\fR, \fBVerifyCAFile\fR, \fBVerifyCAPath\fR" 4 .IX Item "ChainCAFile, ChainCAPath, VerifyCAFile, VerifyCAPath" These options indicate a file or directory used for building certificate chains or verifying certificate chains. These options are only supported if certificate operations are permitted. -.IP "\fBRequestCAFile\fR" 4 +.IP \fBRequestCAFile\fR 4 .IX Item "RequestCAFile" -This option indicates a file containing a set of certificates in \s-1PEM\s0 form. +This option indicates a file containing a set of certificates in PEM form. The subject names of the certificates are sent to the peer in the -\&\fBcertificate_authorities\fR extension for \s-1TLS 1.3\s0 (in ClientHello or +\&\fBcertificate_authorities\fR extension for TLS 1.3 (in ClientHello or CertificateRequest) or in a certificate request for previous versions or -\&\s-1TLS.\s0 -.IP "\fBServerInfoFile\fR" 4 +TLS. +.IP \fBServerInfoFile\fR 4 .IX Item "ServerInfoFile" -Attempts to use the file \fBvalue\fR in the \*(L"serverinfo\*(R" extension using the +Attempts to use the file \fBvalue\fR in the "serverinfo" extension using the function SSL_CTX_use_serverinfo_file. -.IP "\fBDHParameters\fR" 4 +.IP \fBDHParameters\fR 4 .IX Item "DHParameters" -Attempts to use the file \fBvalue\fR as the set of temporary \s-1DH\s0 parameters for +Attempts to use the file \fBvalue\fR as the set of temporary DH parameters for the appropriate context. This option is only supported if certificate operations are permitted. -.IP "\fBRecordPadding\fR" 4 +.IP \fBRecordPadding\fR 4 .IX Item "RecordPadding" -Attempts to pad TLSv1.3 records so that they are a multiple of \fBvalue\fR in -length on send. A \fBvalue\fR of 0 or 1 turns off padding. Otherwise, the -\&\fBvalue\fR must be >1 or <=16384. -.IP "\fBSignatureAlgorithms\fR" 4 +Controls use of TLSv1.3 record layer padding. \fBvalue\fR is a string of the form +"number[,number]" where the (required) first number is the padding block size +(in octets) for application data, and the optional second number is the padding +block size for handshake and alert messages. If the optional second number is +omitted, the same padding will be applied to all messages. +.Sp +Padding attempts to pad TLSv1.3 records so that they are a multiple of the set +length on send. A value of 0 or 1 turns off padding as relevant. Otherwise, the +values must be >1 or <=16384. +.IP \fBSignatureAlgorithms\fR 4 .IX Item "SignatureAlgorithms" This sets the supported signature algorithms for TLSv1.2 and TLSv1.3. For clients this @@ -425,21 +423,25 @@ servers it is used to determine which signature algorithms to support. .Sp The \fBvalue\fR argument should be a colon separated list of signature algorithms in order of decreasing preference of the form \fBalgorithm+hash\fR or -\&\fBsignature_scheme\fR. \fBalgorithm\fR -is one of \fB\s-1RSA\s0\fR, \fB\s-1DSA\s0\fR or \fB\s-1ECDSA\s0\fR and \fBhash\fR is a supported algorithm -\&\s-1OID\s0 short name such as \fB\s-1SHA1\s0\fR, \fB\s-1SHA224\s0\fR, \fB\s-1SHA256\s0\fR, \fB\s-1SHA384\s0\fR of \fB\s-1SHA512\s0\fR. -Note: algorithm and hash names are case sensitive. +\&\fBsignature_scheme\fR. For the default providers shipped with OpenSSL, +\&\fBalgorithm\fR is one of \fBRSA\fR, \fBDSA\fR or \fBECDSA\fR and \fBhash\fR is a supported +algorithm OID short name such as \fBSHA1\fR, \fBSHA224\fR, \fBSHA256\fR, \fBSHA384\fR +or \fBSHA512\fR. \&\fBsignature_scheme\fR is one of the signature schemes defined in TLSv1.3, -specified using the \s-1IETF\s0 name, e.g., \fBecdsa_secp256r1_sha256\fR, \fBed25519\fR, +specified using the IANA name, e.g., \fBecdsa_secp256r1_sha256\fR, \fBed25519\fR, or \fBrsa_pss_pss_sha256\fR. +Signature scheme names and public key algorithm names (but not the hash names) +in the \fBalgorithm+hash\fR form are case-insensitive. +Additional providers may make available further signature schemes via the +TLS_SIGALG capability. See "CAPABILITIES" in \fBprovider\-base\fR\|(7). .Sp -If this option is not set then all signature algorithms supported by the -OpenSSL library are permissible. +If this option is not set then all signature algorithms supported by all +activated providers are permissible. .Sp Note: algorithms which specify a PKCS#1 v1.5 signature scheme (either by -using \fB\s-1RSA\s0\fR as the \fBalgorithm\fR or by using one of the \fBrsa_pkcs1_*\fR +using \fBRSA\fR as the \fBalgorithm\fR or by using one of the \fBrsa_pkcs1_*\fR identifiers) are ignored in TLSv1.3 and will not be negotiated. -.IP "\fBClientSignatureAlgorithms\fR" 4 +.IP \fBClientSignatureAlgorithms\fR 4 .IX Item "ClientSignatureAlgorithms" This sets the supported signature algorithms associated with client authentication for TLSv1.2 and TLSv1.3. @@ -451,7 +453,7 @@ If a server does not request a certificate this option has no effect. .Sp The syntax of \fBvalue\fR is identical to \fBSignatureAlgorithms\fR. If not set then the value set for \fBSignatureAlgorithms\fR will be used instead. -.IP "\fBGroups\fR" 4 +.IP \fBGroups\fR 4 .IX Item "Groups" This sets the supported groups. For clients, the groups are sent using the supported groups extension. For servers, it is used @@ -460,44 +462,59 @@ signatures (in TLSv1.2 and earlier) and key exchange. The first group listed will also be used for the \fBkey_share\fR sent by a client in a TLSv1.3 \&\fBClientHello\fR. .Sp -The \fBvalue\fR argument is a colon separated list of groups. The group can be -either the \fB\s-1NIST\s0\fR name (e.g. \fBP\-256\fR), some other commonly used name where -applicable (e.g. \fBX25519\fR, \fBffdhe2048\fR) or an OpenSSL \s-1OID\s0 name -(e.g. \fBprime256v1\fR). Group names are case sensitive. The list should be in -order of preference with the most preferred group first. +The \fBgroups\fR argument is a colon separated list of groups. The preferred +names are those listed in the IANA +TLS Supported Groups <https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-8> +registry. +For some groups, OpenSSL supports additional aliases. +Such an alias could be a \fBNIST\fR name (e.g. \fBP\-256\fR), an OpenSSL OID name +(e.g. \fBprime256v1\fR), or some other commonly used name. +Group names are case-insensitive in OpenSSL 3.5 and later. +The list should be in order of preference with the most preferred group first. .Sp -Currently supported groups for \fBTLSv1.3\fR are \fBP\-256\fR, \fBP\-384\fR, \fBP\-521\fR, -\&\fBX25519\fR, \fBX448\fR, \fBffdhe2048\fR, \fBffdhe3072\fR, \fBffdhe4096\fR, \fBffdhe6144\fR, -\&\fBffdhe8192\fR. -.IP "\fBCurves\fR" 4 +The commands below list the available groups for TLS 1.2 and TLS 1.3, +respectively: +.Sp +.Vb 2 +\& $ openssl list \-tls1_2 \-tls\-groups +\& $ openssl list \-tls1_3 \-tls\-groups +.Ve +.Sp +An enriched alternative syntax, that enables clients to send multiple keyshares +and allows servers to prioritise some groups over others, is described in +\&\fBSSL_CTX_set1_groups_list\fR\|(3). +Since TLS 1.2 has neither keyshares nor a hello retry mechanism, with TLS 1.2 +the enriched syntax is ultimately equivalent to just a simple ordered list of +groups, as with the simple form above. +.IP \fBCurves\fR 4 .IX Item "Curves" -This is a synonym for the \*(L"Groups\*(R" command. -.IP "\fBMinProtocol\fR" 4 +This is a synonym for the "Groups" command. +.IP \fBMinProtocol\fR 4 .IX Item "MinProtocol" -This sets the minimum supported \s-1SSL, TLS\s0 or \s-1DTLS\s0 version. +This sets the minimum supported SSL, TLS or DTLS version. .Sp Currently supported protocol values are \fBSSLv3\fR, \fBTLSv1\fR, \fBTLSv1.1\fR, \&\fBTLSv1.2\fR, \fBTLSv1.3\fR, \fBDTLSv1\fR and \fBDTLSv1.2\fR. -The \s-1SSL\s0 and \s-1TLS\s0 bounds apply only to TLS-based contexts, while the \s-1DTLS\s0 bounds +The SSL and TLS bounds apply only to TLS-based contexts, while the DTLS bounds apply only to DTLS-based contexts. -The command can be repeated with one instance setting a \s-1TLS\s0 bound, and the -other setting a \s-1DTLS\s0 bound. +The command can be repeated with one instance setting a TLS bound, and the +other setting a DTLS bound. The value \fBNone\fR applies to both types of contexts and disables the limits. -.IP "\fBMaxProtocol\fR" 4 +.IP \fBMaxProtocol\fR 4 .IX Item "MaxProtocol" -This sets the maximum supported \s-1SSL, TLS\s0 or \s-1DTLS\s0 version. +This sets the maximum supported SSL, TLS or DTLS version. .Sp Currently supported protocol values are \fBSSLv3\fR, \fBTLSv1\fR, \fBTLSv1.1\fR, \&\fBTLSv1.2\fR, \fBTLSv1.3\fR, \fBDTLSv1\fR and \fBDTLSv1.2\fR. -The \s-1SSL\s0 and \s-1TLS\s0 bounds apply only to TLS-based contexts, while the \s-1DTLS\s0 bounds +The SSL and TLS bounds apply only to TLS-based contexts, while the DTLS bounds apply only to DTLS-based contexts. -The command can be repeated with one instance setting a \s-1TLS\s0 bound, and the -other setting a \s-1DTLS\s0 bound. +The command can be repeated with one instance setting a TLS bound, and the +other setting a DTLS bound. The value \fBNone\fR applies to both types of contexts and disables the limits. -.IP "\fBProtocol\fR" 4 +.IP \fBProtocol\fR 4 .IX Item "Protocol" -This can be used to enable or disable certain versions of the \s-1SSL, -TLS\s0 or \s-1DTLS\s0 protocol. +This can be used to enable or disable certain versions of the SSL, +TLS or DTLS protocol. .Sp The \fBvalue\fR argument is a comma separated list of supported protocols to enable or disable. @@ -511,7 +528,7 @@ versions. .Sp Currently supported protocol values are \fBSSLv3\fR, \fBTLSv1\fR, \fBTLSv1.1\fR, \&\fBTLSv1.2\fR, \fBTLSv1.3\fR, \fBDTLSv1\fR and \fBDTLSv1.2\fR. -The special value \fB\s-1ALL\s0\fR refers to all supported versions. +The special value \fBALL\fR refers to all supported versions. .Sp This can't enable protocols that are disabled using \fBMinProtocol\fR or \fBMaxProtocol\fR, but can disable protocols that are still allowed @@ -520,9 +537,9 @@ by them. The \fBProtocol\fR command is fragile and deprecated; do not use it. Use \fBMinProtocol\fR and \fBMaxProtocol\fR instead. If you do use \fBProtocol\fR, make sure that the resulting range of enabled -protocols has no \*(L"holes\*(R", e.g. if \s-1TLS 1.0\s0 and \s-1TLS 1.2\s0 are both enabled, make -sure to also leave \s-1TLS 1.1\s0 enabled. -.IP "\fBOptions\fR" 4 +protocols has no "holes", e.g. if TLS 1.0 and TLS 1.2 are both enabled, make +sure to also leave TLS 1.1 enabled. +.IP \fBOptions\fR 4 .IX Item "Options" The \fBvalue\fR argument is a comma separated list of various flags to set. If a flag string is preceded \fB\-\fR it is disabled. @@ -533,59 +550,64 @@ Each option is listed below. Where an operation is enabled by default the \fB\-flag\fR syntax is needed to disable it. .Sp \&\fBSessionTicket\fR: session ticket support, enabled by default. Inverse of -\&\fB\s-1SSL_OP_NO_TICKET\s0\fR: that is \fB\-SessionTicket\fR is the same as setting -\&\fB\s-1SSL_OP_NO_TICKET\s0\fR. +\&\fBSSL_OP_NO_TICKET\fR: that is \fB\-SessionTicket\fR is the same as setting +\&\fBSSL_OP_NO_TICKET\fR. .Sp -\&\fBCompression\fR: \s-1SSL/TLS\s0 compression support, disabled by default. Inverse -of \fB\s-1SSL_OP_NO_COMPRESSION\s0\fR. +\&\fBCompression\fR: SSL/TLS compression support, disabled by default. Inverse +of \fBSSL_OP_NO_COMPRESSION\fR. .Sp \&\fBEmptyFragments\fR: use empty fragments as a countermeasure against a -\&\s-1SSL 3.0/TLS 1.0\s0 protocol vulnerability affecting \s-1CBC\s0 ciphers. It -is set by default. Inverse of \fB\s-1SSL_OP_DONT_INSERT_EMPTY_FRAGMENTS\s0\fR. +SSL 3.0/TLS 1.0 protocol vulnerability affecting CBC ciphers. It +is set by default. Inverse of \fBSSL_OP_DONT_INSERT_EMPTY_FRAGMENTS\fR. .Sp -\&\fBBugs\fR: enable various bug workarounds. Same as \fB\s-1SSL_OP_ALL\s0\fR. +\&\fBBugs\fR: enable various bug workarounds. Same as \fBSSL_OP_ALL\fR. .Sp -\&\fBDHSingle\fR: enable single use \s-1DH\s0 keys, set by default. Inverse of -\&\fB\s-1SSL_OP_DH_SINGLE\s0\fR. Only used by servers. +\&\fBDHSingle\fR: enable single use DH keys, set by default. Inverse of +\&\fBSSL_OP_DH_SINGLE\fR. Only used by servers. .Sp -\&\fBECDHSingle\fR: enable single use \s-1ECDH\s0 keys, set by default. Inverse of -\&\fB\s-1SSL_OP_ECDH_SINGLE\s0\fR. Only used by servers. +\&\fBECDHSingle\fR: enable single use ECDH keys, set by default. Inverse of +\&\fBSSL_OP_ECDH_SINGLE\fR. Only used by servers. .Sp \&\fBServerPreference\fR: use server and not client preference order when determining which cipher suite, signature algorithm or elliptic curve to use for an incoming connection. Equivalent to -\&\fB\s-1SSL_OP_CIPHER_SERVER_PREFERENCE\s0\fR. Only used by servers. +\&\fBSSL_OP_CIPHER_SERVER_PREFERENCE\fR. Only used by servers. .Sp \&\fBPrioritizeChaCha\fR: prioritizes ChaCha ciphers when the client has a ChaCha20 cipher at the top of its preference list. This usually indicates -a mobile client is in use. Equivalent to \fB\s-1SSL_OP_PRIORITIZE_CHACHA\s0\fR. +a mobile client is in use. Equivalent to \fBSSL_OP_PRIORITIZE_CHACHA\fR. Only used by servers. .Sp \&\fBNoResumptionOnRenegotiation\fR: set -\&\fB\s-1SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION\s0\fR flag. Only used by servers. +\&\fBSSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION\fR flag. Only used by servers. .Sp \&\fBNoRenegotiation\fR: disables all attempts at renegotiation in TLSv1.2 and -earlier, same as setting \fB\s-1SSL_OP_NO_RENEGOTIATION\s0\fR. +earlier, same as setting \fBSSL_OP_NO_RENEGOTIATION\fR. .Sp \&\fBUnsafeLegacyRenegotiation\fR: permits the use of unsafe legacy renegotiation. -Equivalent to \fB\s-1SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION\s0\fR. +Equivalent to \fBSSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION\fR. .Sp \&\fBUnsafeLegacyServerConnect\fR: permits the use of unsafe legacy renegotiation -for OpenSSL clients only. Equivalent to \fB\s-1SSL_OP_LEGACY_SERVER_CONNECT\s0\fR. +for OpenSSL clients only. Equivalent to \fBSSL_OP_LEGACY_SERVER_CONNECT\fR. .Sp \&\fBEncryptThenMac\fR: use encrypt-then-mac extension, enabled by -default. Inverse of \fB\s-1SSL_OP_NO_ENCRYPT_THEN_MAC\s0\fR: that is, -\&\fB\-EncryptThenMac\fR is the same as setting \fB\s-1SSL_OP_NO_ENCRYPT_THEN_MAC\s0\fR. +default. Inverse of \fBSSL_OP_NO_ENCRYPT_THEN_MAC\fR: that is, +\&\fB\-EncryptThenMac\fR is the same as setting \fBSSL_OP_NO_ENCRYPT_THEN_MAC\fR. .Sp \&\fBAllowNoDHEKEX\fR: In TLSv1.3 allow a non\-(ec)dhe based key exchange mode on resumption. This means that there will be no forward secrecy for the resumed -session. Equivalent to \fB\s-1SSL_OP_ALLOW_NO_DHE_KEX\s0\fR. +session. Equivalent to \fBSSL_OP_ALLOW_NO_DHE_KEX\fR. +.Sp +\&\fBPreferNoDHEKEX\fR: In TLSv1.3, on resumption let the server prefer a +non\-(ec)dhe based key exchange mode over an (ec)dhe based one. Requires +\&\fBAllowNoDHEKEX\fR. Equivalent to \fBSSL_OP_PREFER_NO_DHE_KEX\fR. Only used by +servers. .Sp -\&\fBMiddleboxCompat\fR: If set then dummy Change Cipher Spec (\s-1CCS\s0) messages are sent +\&\fBMiddleboxCompat\fR: If set then dummy Change Cipher Spec (CCS) messages are sent in TLSv1.3. This has the effect of making TLSv1.3 look more like TLSv1.2 so that middleboxes that do not understand TLSv1.3 will not drop the connection. This option is set by default. A future version of OpenSSL may not set this by -default. Equivalent to \fB\s-1SSL_OP_ENABLE_MIDDLEBOX_COMPAT\s0\fR. +default. Equivalent to \fBSSL_OP_ENABLE_MIDDLEBOX_COMPAT\fR. .Sp \&\fBAntiReplay\fR: If set then OpenSSL will automatically detect if a session ticket has been used more than once, TLSv1.3 has been negotiated, and early data is @@ -594,20 +616,44 @@ second or subsequent time. This option is set by default and is only used by servers. Anti-replay measures are required to comply with the TLSv1.3 specification. Some applications may be able to mitigate the replay risks in other ways and in such cases the built-in OpenSSL functionality is not required. -Disabling anti-replay is equivalent to setting \fB\s-1SSL_OP_NO_ANTI_REPLAY\s0\fR. +Disabling anti-replay is equivalent to setting \fBSSL_OP_NO_ANTI_REPLAY\fR. .Sp \&\fBExtendedMasterSecret\fR: use extended master secret extension, enabled by -default. Inverse of \fB\s-1SSL_OP_NO_EXTENDED_MASTER_SECRET\s0\fR: that is, -\&\fB\-ExtendedMasterSecret\fR is the same as setting \fB\s-1SSL_OP_NO_EXTENDED_MASTER_SECRET\s0\fR. +default. Inverse of \fBSSL_OP_NO_EXTENDED_MASTER_SECRET\fR: that is, +\&\fB\-ExtendedMasterSecret\fR is the same as setting \fBSSL_OP_NO_EXTENDED_MASTER_SECRET\fR. .Sp -\&\fBCANames\fR: use \s-1CA\s0 names extension, enabled by -default. Inverse of \fB\s-1SSL_OP_DISABLE_TLSEXT_CA_NAMES\s0\fR: that is, -\&\fB\-CANames\fR is the same as setting \fB\s-1SSL_OP_DISABLE_TLSEXT_CA_NAMES\s0\fR. +\&\fBCANames\fR: use CA names extension, enabled by +default. Inverse of \fBSSL_OP_DISABLE_TLSEXT_CA_NAMES\fR: that is, +\&\fB\-CANames\fR is the same as setting \fBSSL_OP_DISABLE_TLSEXT_CA_NAMES\fR. .Sp -\&\fB\s-1KTLS\s0\fR: Enables kernel \s-1TLS\s0 if support has been compiled in, and it is supported +\&\fBKTLS\fR: Enables kernel TLS if support has been compiled in, and it is supported by the negotiated ciphersuites and extensions. Equivalent to -\&\fB\s-1SSL_OP_ENABLE_KTLS\s0\fR. -.IP "\fBVerifyMode\fR" 4 +\&\fBSSL_OP_ENABLE_KTLS\fR. +.Sp +\&\fBStrictCertCheck\fR: Enable strict certificate checking. Equivalent to +setting \fBSSL_CERT_FLAG_TLS_STRICT\fR with \fBSSL_CTX_set_cert_flags()\fR. +.Sp +\&\fBTxCertificateCompression\fR: support sending compressed certificates, enabled by +default. Inverse of \fBSSL_OP_NO_TX_CERTIFICATE_COMPRESSION\fR: that is, +\&\fB\-TxCertificateCompression\fR is the same as setting \fBSSL_OP_NO_TX_CERTIFICATE_COMPRESSION\fR. +.Sp +\&\fBRxCertificateCompression\fR: support receiving compressed certificates, enabled by +default. Inverse of \fBSSL_OP_NO_RX_CERTIFICATE_COMPRESSION\fR: that is, +\&\fB\-RxCertificateCompression\fR is the same as setting \fBSSL_OP_NO_RX_CERTIFICATE_COMPRESSION\fR. +.Sp +\&\fBKTLSTxZerocopySendfile\fR: use the zerocopy TX mode of \fBsendfile()\fR, which gives +a performance boost when used with KTLS hardware offload. Note that invalid TLS +records might be transmitted if the file is changed while being sent. This +option has no effect if \fBKTLS\fR is not enabled. Equivalent to +\&\fBSSL_OP_ENABLE_KTLS_TX_ZEROCOPY_SENDFILE\fR. This option only applies to Linux. +KTLS sendfile on FreeBSD doesn't offer an option to disable zerocopy and +always runs in this mode. +.Sp +\&\fBIgnoreUnexpectedEOF\fR: Equivalent to \fBSSL_OP_IGNORE_UNEXPECTED_EOF\fR. +You should only enable this option if the protocol running over TLS can detect +a truncation attack itself, and that the application is checking for that +truncation attack. +.IP \fBVerifyMode\fR 4 .IX Item "VerifyMode" The \fBvalue\fR argument is a comma separated list of flags to set. .Sp @@ -635,31 +681,31 @@ during the initial handshake. The server application must provide a mechanism to request a certificate post-handshake. Servers only. TLSv1.3 only. .IP "\fBClientCAFile\fR, \fBClientCAPath\fR" 4 .IX Item "ClientCAFile, ClientCAPath" -A file or directory of certificates in \s-1PEM\s0 format whose names are used as the +A file or directory of certificates in PEM format whose names are used as the set of acceptable names for client CAs. Servers only. This option is only supported if certificate operations are permitted. .SH "SUPPORTED COMMAND TYPES" .IX Header "SUPPORTED COMMAND TYPES" The function \fBSSL_CONF_cmd_value_type()\fR currently returns one of the following types: -.IP "\fB\s-1SSL_CONF_TYPE_UNKNOWN\s0\fR" 4 +.IP \fBSSL_CONF_TYPE_UNKNOWN\fR 4 .IX Item "SSL_CONF_TYPE_UNKNOWN" The \fBoption\fR string is unrecognised, this return value can be use to flag syntax errors. -.IP "\fB\s-1SSL_CONF_TYPE_STRING\s0\fR" 4 +.IP \fBSSL_CONF_TYPE_STRING\fR 4 .IX Item "SSL_CONF_TYPE_STRING" The value is a string without any specific structure. -.IP "\fB\s-1SSL_CONF_TYPE_FILE\s0\fR" 4 +.IP \fBSSL_CONF_TYPE_FILE\fR 4 .IX Item "SSL_CONF_TYPE_FILE" The value is a filename. -.IP "\fB\s-1SSL_CONF_TYPE_DIR\s0\fR" 4 +.IP \fBSSL_CONF_TYPE_DIR\fR 4 .IX Item "SSL_CONF_TYPE_DIR" The value is a directory name. -.IP "\fB\s-1SSL_CONF_TYPE_NONE\s0\fR" 4 +.IP \fBSSL_CONF_TYPE_NONE\fR 4 .IX Item "SSL_CONF_TYPE_NONE" The value string is not used e.g. a command line option which doesn't take an argument. -.SH "NOTES" +.SH NOTES .IX Header "NOTES" The order of operations is significant. This can be used to set either defaults or values which cannot be overridden. For example if an application calls: @@ -692,7 +738,7 @@ Applications can also use \fBSSL_CONF_cmd()\fR to process command lines though t utility function \fBSSL_CONF_cmd_argv()\fR is normally used instead. One way to do this is to set the prefix to an appropriate value using \&\fBSSL_CONF_CTX_set1_prefix()\fR, pass the current argument to \fBoption\fR and the -following argument to \fBvalue\fR (which may be \s-1NULL\s0). +following argument to \fBvalue\fR (which may be NULL). .PP In this case if the return value is positive then it is used to skip that number of arguments as they have been processed by \fBSSL_CONF_cmd()\fR. If \-2 is @@ -704,25 +750,25 @@ this can be reported back to the user. The function \fBSSL_CONF_cmd_value_type()\fR can be used by applications to check for the existence of a command or to perform additional syntax checking or translation of the command value. For example if the return -value is \fB\s-1SSL_CONF_TYPE_FILE\s0\fR an application could translate a relative +value is \fBSSL_CONF_TYPE_FILE\fR an application could translate a relative pathname to an absolute pathname. .SH "RETURN VALUES" .IX Header "RETURN VALUES" \&\fBSSL_CONF_cmd()\fR returns 1 if the value of \fBoption\fR is recognised and \fBvalue\fR is -\&\fB\s-1NOT\s0\fR used and 2 if both \fBoption\fR and \fBvalue\fR are used. In other words it +\&\fBNOT\fR used and 2 if both \fBoption\fR and \fBvalue\fR are used. In other words it returns the number of arguments processed. This is useful when processing command lines. .PP A return value of \-2 means \fBoption\fR is not recognised. .PP A return value of \-3 means \fBoption\fR is recognised and the command requires a -value but \fBvalue\fR is \s-1NULL.\s0 +value but \fBvalue\fR is NULL. .PP A return code of 0 indicates that both \fBoption\fR and \fBvalue\fR are valid but an error occurred attempting to perform the operation: for example due to an error in the syntax of \fBvalue\fR in this case the error queue may provide additional information. -.SH "EXAMPLES" +.SH EXAMPLES .IX Header "EXAMPLES" Set supported signature algorithms: .PP @@ -748,7 +794,7 @@ The following also disables SSLv3: The following will first enable all protocols, and then disable SSLv3. If no protocol versions were disabled before this has the same effect as -\&\*(L"\-SSLv3\*(R", but if some versions were disables this will re-enable them before +"\-SSLv3", but if some versions were disables this will re-enable them before disabling SSLv3. .PP .Vb 1 @@ -768,7 +814,7 @@ This also only enables TLSv1.2: \& SSL_CONF_cmd(ctx, "Protocol", "\-ALL,TLSv1.2"); .Ve .PP -Disable \s-1TLS\s0 session tickets: +Disable TLS session tickets: .PP .Vb 1 \& SSL_CONF_cmd(ctx, "Options", "\-SessionTicket"); @@ -794,16 +840,16 @@ Set supported curves to P\-256, P\-384: \&\fBSSL_CONF_CTX_set_ssl_ctx\fR\|(3), \&\fBSSL_CONF_cmd_argv\fR\|(3), \&\fBSSL_CTX_set_options\fR\|(3) -.SH "HISTORY" +.SH HISTORY .IX Header "HISTORY" The \fBSSL_CONF_cmd()\fR function was added in OpenSSL 1.0.2. .PP -The \fB\s-1SSL_OP_NO_SSL2\s0\fR option doesn't have effect since 1.1.0, but the macro +The \fBSSL_OP_NO_SSL2\fR option doesn't have effect since 1.1.0, but the macro is retained for backwards compatibility. .PP -The \fB\s-1SSL_CONF_TYPE_NONE\s0\fR was added in OpenSSL 1.1.0. In earlier versions of +The \fBSSL_CONF_TYPE_NONE\fR was added in OpenSSL 1.1.0. In earlier versions of OpenSSL passing a command which didn't take an argument would return -\&\fB\s-1SSL_CONF_TYPE_UNKNOWN\s0\fR. +\&\fBSSL_CONF_TYPE_UNKNOWN\fR. .PP \&\fBMinProtocol\fR and \fBMaxProtocol\fR where added in OpenSSL 1.1.0. .PP @@ -811,11 +857,34 @@ OpenSSL passing a command which didn't take an argument would return .PP The \fBUnsafeLegacyServerConnect\fR option is no longer set by default from OpenSSL 3.0. -.SH "COPYRIGHT" +.PP +The \fBTxCertificateCompression\fR and \fBRxCertificateCompression\fR options were +added in OpenSSL 3.2. +.PP +\&\fBPreferNoDHEKEX\fR was added in OpenSSL 3.3. +.PP +OpenSSL 3.5 introduces support for post-quantum (PQ) TLS key exchange via the +\&\fBMLKEM512\fR, \fBMLKEM768\fR and \fBMLKEM1024\fR TLS groups. +These are based on the underlying \fBML\-KEM\-512\fR, \fBML\-KEM\-768\fR and +\&\fBML\-KEM\-1024\fR algorithms from FIPS 203. +.PP +OpenSSL 3.5 also introduces support for three \fBhybrid\fR ECDH PQ key exchange +TLS groups: \fBX25519MLKEM768\fR, \fBSecP256r1MLKEM768\fR and +\&\fBSecP384r1MLKEM1024\fR. +They offer CPU performance comparable to the associated ECDH group, though at +the cost of significantly larger key exchange messages. +The third group, \fBSecP384r1MLKEM1024\fR is substantially more CPU-intensive, +largely as a result of the high CPU cost of ECDH for the underlying \fBP\-384\fR +group. +Also its key exchange messages at close to 1700 bytes are larger than the +roughly 1200 bytes for the first two groups. +.PP +As of OpenSSL 3.5 key exchange group names are case-insensitive. +.SH COPYRIGHT .IX Header "COPYRIGHT" -Copyright 2012\-2022 The OpenSSL Project Authors. All Rights Reserved. +Copyright 2012\-2025 The OpenSSL Project Authors. All Rights Reserved. .PP -Licensed under the Apache License 2.0 (the \*(L"License\*(R"). You may not use +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 \s-1LICENSE\s0 in the source distribution or at +in the file LICENSE in the source distribution or at <https://www.openssl.org/source/license.html>. |