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- .\" -*- mode: troff; coding: utf-8 -*-
- .\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43)
- .\"
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- .\" ========================================================================
- .de Sp \" Vertical space (when we can't use .PP)
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- .\"
- .\" 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
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- .\" Avoid warning from groff about undefined register 'F'.
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- .\" ========================================================================
- .\"
- .IX Title "OPENSSL-SMIME 1ossl"
- .TH OPENSSL-SMIME 1ossl 2025-01-17 3.4.0 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
- openssl\-smime \- S/MIME command
- .SH SYNOPSIS
- .IX Header "SYNOPSIS"
- \&\fBopenssl\fR \fBsmime\fR
- [\fB\-help\fR]
- [\fB\-encrypt\fR]
- [\fB\-decrypt\fR]
- [\fB\-sign\fR]
- [\fB\-resign\fR]
- [\fB\-verify\fR]
- [\fB\-pk7out\fR]
- [\fB\-binary\fR]
- [\fB\-crlfeol\fR]
- [\fB\-\fR\f(BIcipher\fR]
- [\fB\-in\fR \fIfile\fR]
- [\fB\-certfile\fR \fIfile\fR]
- [\fB\-signer\fR \fIfile\fR]
- [\fB\-nointern\fR]
- [\fB\-noverify\fR]
- [\fB\-nochain\fR]
- [\fB\-nosigs\fR]
- [\fB\-nocerts\fR]
- [\fB\-noattr\fR]
- [\fB\-nodetach\fR]
- [\fB\-nosmimecap\fR]
- [\fB\-recip\fR \fI file\fR]
- [\fB\-inform\fR \fBDER\fR|\fBPEM\fR|\fBSMIME\fR]
- [\fB\-outform\fR \fBDER\fR|\fBPEM\fR|\fBSMIME\fR]
- [\fB\-keyform\fR \fBDER\fR|\fBPEM\fR|\fBP12\fR|\fBENGINE\fR]
- [\fB\-passin\fR \fIarg\fR]
- [\fB\-inkey\fR \fIfilename\fR|\fIuri\fR]
- [\fB\-out\fR \fIfile\fR]
- [\fB\-content\fR \fIfile\fR]
- [\fB\-to\fR \fIaddr\fR]
- [\fB\-from\fR \fIad\fR]
- [\fB\-subject\fR \fIs\fR]
- [\fB\-text\fR]
- [\fB\-indef\fR]
- [\fB\-noindef\fR]
- [\fB\-stream\fR]
- [\fB\-md\fR \fIdigest\fR]
- [\fB\-CAfile\fR \fIfile\fR]
- [\fB\-no\-CAfile\fR]
- [\fB\-CApath\fR \fIdir\fR]
- [\fB\-no\-CApath\fR]
- [\fB\-CAstore\fR \fIuri\fR]
- [\fB\-no\-CAstore\fR]
- [\fB\-engine\fR \fIid\fR]
- [\fB\-rand\fR \fIfiles\fR]
- [\fB\-writerand\fR \fIfile\fR]
- [\fB\-allow_proxy_certs\fR]
- [\fB\-attime\fR \fItimestamp\fR]
- [\fB\-no_check_time\fR]
- [\fB\-check_ss_sig\fR]
- [\fB\-crl_check\fR]
- [\fB\-crl_check_all\fR]
- [\fB\-explicit_policy\fR]
- [\fB\-extended_crl\fR]
- [\fB\-ignore_critical\fR]
- [\fB\-inhibit_any\fR]
- [\fB\-inhibit_map\fR]
- [\fB\-partial_chain\fR]
- [\fB\-policy\fR \fIarg\fR]
- [\fB\-policy_check\fR]
- [\fB\-policy_print\fR]
- [\fB\-purpose\fR \fIpurpose\fR]
- [\fB\-suiteB_128\fR]
- [\fB\-suiteB_128_only\fR]
- [\fB\-suiteB_192\fR]
- [\fB\-trusted_first\fR]
- [\fB\-no_alt_chains\fR]
- [\fB\-use_deltas\fR]
- [\fB\-auth_level\fR \fInum\fR]
- [\fB\-verify_depth\fR \fInum\fR]
- [\fB\-verify_email\fR \fIemail\fR]
- [\fB\-verify_hostname\fR \fIhostname\fR]
- [\fB\-verify_ip\fR \fIip\fR]
- [\fB\-verify_name\fR \fIname\fR]
- [\fB\-x509_strict\fR]
- [\fB\-issuer_checks\fR]
- [\fB\-provider\fR \fIname\fR]
- [\fB\-provider\-path\fR \fIpath\fR]
- [\fB\-propquery\fR \fIpropq\fR]
- [\fB\-config\fR \fIconfigfile\fR]
- \&\fIrecipcert\fR ...
- .SH DESCRIPTION
- .IX Header "DESCRIPTION"
- This command handles S/MIME mail. It can encrypt, decrypt, sign
- and verify S/MIME messages.
- .SH OPTIONS
- .IX Header "OPTIONS"
- There are six operation options that set the type of operation to be performed:
- \&\fB\-encrypt\fR, \fB\-decrypt\fR, \fB\-sign\fR, \fB\-resign\fR, \fB\-verify\fR, and \fB\-pk7out\fR.
- These are mutually exclusive.
- The meaning of the other options varies according to the operation type.
- .IP \fB\-help\fR 4
- .IX Item "-help"
- Print out a usage message.
- .IP \fB\-encrypt\fR 4
- .IX Item "-encrypt"
- Encrypt mail for the given recipient certificates. Input file is the message
- to be encrypted. The output file is the encrypted mail in MIME format.
- .Sp
- Note that no revocation check is done for the recipient cert, so if that
- key has been compromised, others may be able to decrypt the text.
- .IP \fB\-decrypt\fR 4
- .IX Item "-decrypt"
- Decrypt mail using the supplied certificate and private key. Expects an
- encrypted mail message in MIME format for the input file. The decrypted mail
- is written to the output file.
- .IP \fB\-sign\fR 4
- .IX Item "-sign"
- Sign mail using the supplied certificate and private key. Input file is
- the message to be signed. The signed message in MIME format is written
- to the output file.
- .IP \fB\-resign\fR 4
- .IX Item "-resign"
- Resign a message: take an existing message and one or more new signers.
- .IP \fB\-verify\fR 4
- .IX Item "-verify"
- Verify signed mail. Expects a signed mail message on input and outputs
- the signed data. Both clear text and opaque signing is supported.
- .IP \fB\-pk7out\fR 4
- .IX Item "-pk7out"
- Takes an input message and writes out a PEM encoded PKCS#7 structure.
- .IP "\fB\-in\fR \fIfilename\fR" 4
- .IX Item "-in filename"
- The input message to be encrypted or signed or the MIME message to
- be decrypted or verified.
- .IP "\fB\-out\fR \fIfilename\fR" 4
- .IX Item "-out filename"
- The message text that has been decrypted or verified or the output MIME
- format message that has been signed or verified.
- .IP "\fB\-inform\fR \fBDER\fR|\fBPEM\fR|\fBSMIME\fR" 4
- .IX Item "-inform DER|PEM|SMIME"
- The input format of the PKCS#7 (S/MIME) structure (if one is being read);
- the default is \fBSMIME\fR.
- See \fBopenssl\-format\-options\fR\|(1) for details.
- .IP "\fB\-outform\fR \fBDER\fR|\fBPEM\fR|\fBSMIME\fR" 4
- .IX Item "-outform DER|PEM|SMIME"
- The output format of the PKCS#7 (S/MIME) structure (if one is being written);
- the default is \fBSMIME\fR.
- See \fBopenssl\-format\-options\fR\|(1) for details.
- .IP "\fB\-keyform\fR \fBDER\fR|\fBPEM\fR|\fBP12\fR|\fBENGINE\fR" 4
- .IX Item "-keyform DER|PEM|P12|ENGINE"
- The key format; unspecified by default.
- See \fBopenssl\-format\-options\fR\|(1) for details.
- .IP "\fB\-stream\fR, \fB\-indef\fR, \fB\-noindef\fR" 4
- .IX Item "-stream, -indef, -noindef"
- The \fB\-stream\fR and \fB\-indef\fR options are equivalent and enable streaming I/O
- for encoding operations. This permits single pass processing of data without
- the need to hold the entire contents in memory, potentially supporting very
- large files. Streaming is automatically set for S/MIME signing with detached
- data if the output format is \fBSMIME\fR it is currently off by default for all
- other operations.
- .IP \fB\-noindef\fR 4
- .IX Item "-noindef"
- Disable streaming I/O where it would produce and indefinite length constructed
- encoding. This option currently has no effect. In future streaming will be
- enabled by default on all relevant operations and this option will disable it.
- .IP "\fB\-content\fR \fIfilename\fR" 4
- .IX Item "-content filename"
- This specifies a file containing the detached content, this is only
- useful with the \fB\-verify\fR command. This is only usable if the PKCS#7
- structure is using the detached signature form where the content is
- not included. This option will override any content if the input format
- is S/MIME and it uses the multipart/signed MIME content type.
- .IP \fB\-text\fR 4
- .IX Item "-text"
- This option adds plain text (text/plain) MIME headers to the supplied
- message if encrypting or signing. If decrypting or verifying it strips
- off text headers: if the decrypted or verified message is not of MIME
- type text/plain then an error occurs.
- .IP "\fB\-md\fR \fIdigest\fR" 4
- .IX Item "-md digest"
- Digest algorithm to use when signing or resigning. If not present then the
- default digest algorithm for the signing key will be used (usually SHA1).
- .IP \fB\-\fR\f(BIcipher\fR 4
- .IX Item "-cipher"
- The encryption algorithm to use. For example DES (56 bits) \- \fB\-des\fR,
- triple DES (168 bits) \- \fB\-des3\fR,
- \&\fBEVP_get_cipherbyname()\fR function) can also be used preceded by a dash, for
- example \fB\-aes\-128\-cbc\fR. See \fBopenssl\-enc\fR\|(1) for list of ciphers
- supported by your version of OpenSSL.
- .Sp
- If not specified triple DES is used. Only used with \fB\-encrypt\fR.
- .IP \fB\-nointern\fR 4
- .IX Item "-nointern"
- When verifying a message normally certificates (if any) included in
- the message are searched for the signing certificate. With this option
- only the certificates specified in the \fB\-certfile\fR option are used.
- The supplied certificates can still be used as untrusted CAs however.
- .IP \fB\-noverify\fR 4
- .IX Item "-noverify"
- Do not verify the signers certificate of a signed message.
- .IP \fB\-nochain\fR 4
- .IX Item "-nochain"
- Do not do chain verification of signers certificates; that is, do not
- use the certificates in the signed message as untrusted CAs.
- .IP \fB\-nosigs\fR 4
- .IX Item "-nosigs"
- Don't try to verify the signatures on the message.
- .IP \fB\-nocerts\fR 4
- .IX Item "-nocerts"
- When signing a message, the signer's certificate is normally included.
- With this option it is excluded. This will reduce the size of the
- signed message, but the verifier must have a copy of the signers certificate
- available locally (passed using the \fB\-certfile\fR option for example).
- .IP \fB\-noattr\fR 4
- .IX Item "-noattr"
- Normally, when a message is signed, a set of attributes are included which
- include the signing time and supported symmetric algorithms. With this
- option they are not included.
- .IP \fB\-nodetach\fR 4
- .IX Item "-nodetach"
- When signing a message use opaque signing. This form is more resistant
- to translation by mail relays but it cannot be read by mail agents that
- do not support S/MIME. Without this option cleartext signing with
- the MIME type multipart/signed is used.
- .IP \fB\-nosmimecap\fR 4
- .IX Item "-nosmimecap"
- When signing a message, do not include the \fBSMIMECapabilities\fR attribute.
- .IP \fB\-binary\fR 4
- .IX Item "-binary"
- Normally the input message is converted to "canonical" format which is
- effectively using CR and LF as end of line: as required by the S/MIME
- specification. When this option is present no translation occurs. This
- is useful when handling binary data which may not be in MIME format.
- .IP \fB\-crlfeol\fR 4
- .IX Item "-crlfeol"
- Normally the output file uses a single \fBLF\fR as end of line. When this
- option is present \fBCRLF\fR is used instead.
- .IP "\fB\-certfile\fR \fIfile\fR" 4
- .IX Item "-certfile file"
- Allows additional certificates to be specified. When signing these will
- be included with the message. When verifying, these will be searched for
- signer certificates and will be used for chain building.
- .Sp
- The input can be in PEM, DER, or PKCS#12 format.
- .IP "\fB\-signer\fR \fIfile\fR" 4
- .IX Item "-signer file"
- A signing certificate when signing or resigning a message, this option can be
- used multiple times if more than one signer is required. If a message is being
- verified then the signers certificates will be written to this file if the
- verification was successful.
- .IP "\fB\-recip\fR \fIfile\fR" 4
- .IX Item "-recip file"
- The recipients certificate when decrypting a message. This certificate
- must match one of the recipients of the message or an error occurs.
- .IP "\fB\-inkey\fR \fIfilename\fR|\fIuri\fR" 4
- .IX Item "-inkey filename|uri"
- The private key to use when signing or decrypting. This must match the
- corresponding certificate. If this option is not specified then the
- private key must be included in the certificate file specified with
- the \fB\-recip\fR or \fB\-signer\fR file. When signing this option can be used
- multiple times to specify successive keys.
- .IP "\fB\-passin\fR \fIarg\fR" 4
- .IX Item "-passin arg"
- The private key password source. For more information about the format of \fIarg\fR
- see \fBopenssl\-passphrase\-options\fR\|(1).
- .IP "\fB\-to\fR, \fB\-from\fR, \fB\-subject\fR" 4
- .IX Item "-to, -from, -subject"
- The relevant mail headers. These are included outside the signed
- portion of a message so they may be included manually. If signing
- then many S/MIME mail clients check the signers certificate's email
- address matches that specified in the From: address.
- .IP "\fB\-allow_proxy_certs\fR, \fB\-attime\fR, \fB\-no_check_time\fR, \fB\-check_ss_sig\fR, \fB\-crl_check\fR, \fB\-crl_check_all\fR, \fB\-explicit_policy\fR, \fB\-extended_crl\fR, \fB\-ignore_critical\fR, \fB\-inhibit_any\fR, \fB\-inhibit_map\fR, \fB\-no_alt_chains\fR, \fB\-partial_chain\fR, \fB\-policy\fR, \fB\-policy_check\fR, \fB\-policy_print\fR, \fB\-purpose\fR, \fB\-suiteB_128\fR, \fB\-suiteB_128_only\fR, \fB\-suiteB_192\fR, \fB\-trusted_first\fR, \fB\-use_deltas\fR, \fB\-auth_level\fR, \fB\-verify_depth\fR, \fB\-verify_email\fR, \fB\-verify_hostname\fR, \fB\-verify_ip\fR, \fB\-verify_name\fR, \fB\-x509_strict\fR \fB\-issuer_checks\fR" 4
- .IX Item "-allow_proxy_certs, -attime, -no_check_time, -check_ss_sig, -crl_check, -crl_check_all, -explicit_policy, -extended_crl, -ignore_critical, -inhibit_any, -inhibit_map, -no_alt_chains, -partial_chain, -policy, -policy_check, -policy_print, -purpose, -suiteB_128, -suiteB_128_only, -suiteB_192, -trusted_first, -use_deltas, -auth_level, -verify_depth, -verify_email, -verify_hostname, -verify_ip, -verify_name, -x509_strict -issuer_checks"
- Set various options of certificate chain verification.
- See "Verification Options" in \fBopenssl\-verification\-options\fR\|(1) for details.
- .Sp
- Any verification errors cause the command to exit.
- .IP "\fB\-CAfile\fR \fIfile\fR, \fB\-no\-CAfile\fR, \fB\-CApath\fR \fIdir\fR, \fB\-no\-CApath\fR, \fB\-CAstore\fR \fIuri\fR, \fB\-no\-CAstore\fR" 4
- .IX Item "-CAfile file, -no-CAfile, -CApath dir, -no-CApath, -CAstore uri, -no-CAstore"
- See "Trusted Certificate Options" in \fBopenssl\-verification\-options\fR\|(1) for details.
- .IP "\fB\-engine\fR \fIid\fR" 4
- .IX Item "-engine id"
- See "Engine Options" in \fBopenssl\fR\|(1).
- This option is deprecated.
- .IP "\fB\-rand\fR \fIfiles\fR, \fB\-writerand\fR \fIfile\fR" 4
- .IX Item "-rand files, -writerand file"
- See "Random State Options" in \fBopenssl\fR\|(1) for details.
- .IP "\fB\-provider\fR \fIname\fR" 4
- .IX Item "-provider name"
- .PD 0
- .IP "\fB\-provider\-path\fR \fIpath\fR" 4
- .IX Item "-provider-path path"
- .IP "\fB\-propquery\fR \fIpropq\fR" 4
- .IX Item "-propquery propq"
- .PD
- See "Provider Options" in \fBopenssl\fR\|(1), \fBprovider\fR\|(7), and \fBproperty\fR\|(7).
- .IP "\fB\-config\fR \fIconfigfile\fR" 4
- .IX Item "-config configfile"
- See "Configuration Option" in \fBopenssl\fR\|(1).
- .IP "\fIrecipcert\fR ..." 4
- .IX Item "recipcert ..."
- One or more certificates of message recipients, used when encrypting
- a message.
- .SH NOTES
- .IX Header "NOTES"
- The MIME message must be sent without any blank lines between the
- headers and the output. Some mail programs will automatically add
- a blank line. Piping the mail directly to sendmail is one way to
- achieve the correct format.
- .PP
- The supplied message to be signed or encrypted must include the
- necessary MIME headers or many S/MIME clients won't display it
- properly (if at all). You can use the \fB\-text\fR option to automatically
- add plain text headers.
- .PP
- A "signed and encrypted" message is one where a signed message is
- then encrypted. This can be produced by encrypting an already signed
- message: see the examples section.
- .PP
- This version of the program only allows one signer per message but it
- will verify multiple signers on received messages. Some S/MIME clients
- choke if a message contains multiple signers. It is possible to sign
- messages "in parallel" by signing an already signed message.
- .PP
- The options \fB\-encrypt\fR and \fB\-decrypt\fR reflect common usage in S/MIME
- clients. Strictly speaking these process PKCS#7 enveloped data: PKCS#7
- encrypted data is used for other purposes.
- .PP
- The \fB\-resign\fR option uses an existing message digest when adding a new
- signer. This means that attributes must be present in at least one existing
- signer using the same message digest or this operation will fail.
- .PP
- The \fB\-stream\fR and \fB\-indef\fR options enable streaming I/O support.
- As a result the encoding is BER using indefinite length constructed encoding
- and no longer DER. Streaming is supported for the \fB\-encrypt\fR operation and the
- \&\fB\-sign\fR operation if the content is not detached.
- .PP
- Streaming is always used for the \fB\-sign\fR operation with detached data but
- since the content is no longer part of the PKCS#7 structure the encoding
- remains DER.
- .SH "EXIT CODES"
- .IX Header "EXIT CODES"
- .IP 0 4
- The operation was completely successfully.
- .IP 1 4
- .IX Item "1"
- An error occurred parsing the command options.
- .IP 2 4
- .IX Item "2"
- One of the input files could not be read.
- .IP 3 4
- .IX Item "3"
- An error occurred creating the PKCS#7 file or when reading the MIME
- message.
- .IP 4 4
- .IX Item "4"
- An error occurred decrypting or verifying the message.
- .IP 5 4
- .IX Item "5"
- The message was verified correctly but an error occurred writing out
- the signers certificates.
- .SH EXAMPLES
- .IX Header "EXAMPLES"
- Create a cleartext signed message:
- .PP
- .Vb 2
- \& openssl smime \-sign \-in message.txt \-text \-out mail.msg \e
- \& \-signer mycert.pem
- .Ve
- .PP
- Create an opaque signed message:
- .PP
- .Vb 2
- \& openssl smime \-sign \-in message.txt \-text \-out mail.msg \-nodetach \e
- \& \-signer mycert.pem
- .Ve
- .PP
- Create a signed message, include some additional certificates and
- read the private key from another file:
- .PP
- .Vb 2
- \& openssl smime \-sign \-in in.txt \-text \-out mail.msg \e
- \& \-signer mycert.pem \-inkey mykey.pem \-certfile mycerts.pem
- .Ve
- .PP
- Create a signed message with two signers:
- .PP
- .Vb 2
- \& openssl smime \-sign \-in message.txt \-text \-out mail.msg \e
- \& \-signer mycert.pem \-signer othercert.pem
- .Ve
- .PP
- Send a signed message under Unix directly to sendmail, including headers:
- .PP
- .Vb 3
- \& openssl smime \-sign \-in in.txt \-text \-signer mycert.pem \e
- \& \-from steve@openssl.org \-to someone@somewhere \e
- \& \-subject "Signed message" | sendmail someone@somewhere
- .Ve
- .PP
- Verify a message and extract the signer's certificate if successful:
- .PP
- .Vb 1
- \& openssl smime \-verify \-in mail.msg \-signer user.pem \-out signedtext.txt
- .Ve
- .PP
- Send encrypted mail using triple DES:
- .PP
- .Vb 3
- \& openssl smime \-encrypt \-in in.txt \-from steve@openssl.org \e
- \& \-to someone@somewhere \-subject "Encrypted message" \e
- \& \-des3 user.pem \-out mail.msg
- .Ve
- .PP
- Sign and encrypt mail:
- .PP
- .Vb 4
- \& openssl smime \-sign \-in ml.txt \-signer my.pem \-text \e
- \& | openssl smime \-encrypt \-out mail.msg \e
- \& \-from steve@openssl.org \-to someone@somewhere \e
- \& \-subject "Signed and Encrypted message" \-des3 user.pem
- .Ve
- .PP
- Note: the encryption command does not include the \fB\-text\fR option because the
- message being encrypted already has MIME headers.
- .PP
- Decrypt mail:
- .PP
- .Vb 1
- \& openssl smime \-decrypt \-in mail.msg \-recip mycert.pem \-inkey key.pem
- .Ve
- .PP
- The output from Netscape form signing is a PKCS#7 structure with the
- detached signature format. You can use this program to verify the
- signature by line wrapping the base64 encoded structure and surrounding
- it with:
- .PP
- .Vb 2
- \& \-\-\-\-\-BEGIN PKCS7\-\-\-\-\-
- \& \-\-\-\-\-END PKCS7\-\-\-\-\-
- .Ve
- .PP
- and using the command:
- .PP
- .Vb 1
- \& openssl smime \-verify \-inform PEM \-in signature.pem \-content content.txt
- .Ve
- .PP
- Alternatively you can base64 decode the signature and use:
- .PP
- .Vb 1
- \& openssl smime \-verify \-inform DER \-in signature.der \-content content.txt
- .Ve
- .PP
- Create an encrypted message using 128 bit Camellia:
- .PP
- .Vb 1
- \& openssl smime \-encrypt \-in plain.txt \-camellia128 \-out mail.msg cert.pem
- .Ve
- .PP
- Add a signer to an existing message:
- .PP
- .Vb 1
- \& openssl smime \-resign \-in mail.msg \-signer newsign.pem \-out mail2.msg
- .Ve
- .SH BUGS
- .IX Header "BUGS"
- The MIME parser isn't very clever: it seems to handle most messages that I've
- thrown at it but it may choke on others.
- .PP
- The code currently will only write out the signer's certificate to a file: if
- the signer has a separate encryption certificate this must be manually
- extracted. There should be some heuristic that determines the correct
- encryption certificate.
- .PP
- Ideally a database should be maintained of a certificates for each email
- address.
- .PP
- The code doesn't currently take note of the permitted symmetric encryption
- algorithms as supplied in the SMIMECapabilities signed attribute. This means the
- user has to manually include the correct encryption algorithm. It should store
- the list of permitted ciphers in a database and only use those.
- .PP
- No revocation checking is done on the signer's certificate.
- .PP
- The current code can only handle S/MIME v2 messages, the more complex S/MIME v3
- structures may cause parsing errors.
- .SH "SEE ALSO"
- .IX Header "SEE ALSO"
- \&\fBossl_store\-file\fR\|(7)
- .SH HISTORY
- .IX Header "HISTORY"
- The use of multiple \fB\-signer\fR options and the \fB\-resign\fR command were first
- added in OpenSSL 1.0.0
- .PP
- The \-no_alt_chains option was added in OpenSSL 1.1.0.
- .PP
- The \fB\-engine\fR option was deprecated in OpenSSL 3.0.
- .SH COPYRIGHT
- .IX Header "COPYRIGHT"
- Copyright 2000\-2024 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>.
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