98 files changed, 5816 insertions, 0 deletions
diff --git a/comm/mailnews/test/data/smime/Alice.p12 b/comm/mailnews/test/data/smime/Alice.p12
new file mode 100644
index 0000000000..5533001a3c
--- /dev/null
+++ b/comm/mailnews/test/data/smime/Alice.p12
diff --git a/comm/mailnews/test/data/smime/Bob.p12 b/comm/mailnews/test/data/smime/Bob.p12
new file mode 100644
index 0000000000..b5c8504a73
--- /dev/null
+++ b/comm/mailnews/test/data/smime/Bob.p12
diff --git a/comm/mailnews/test/data/smime/Dave.p12 b/comm/mailnews/test/data/smime/Dave.p12
new file mode 100644
index 0000000000..ee9fcefe64
--- /dev/null
+++ b/comm/mailnews/test/data/smime/Dave.p12
diff --git a/comm/mailnews/test/data/smime/Eve.p12 b/comm/mailnews/test/data/smime/Eve.p12
new file mode 100644
index 0000000000..c0c3d477fb
--- /dev/null
+++ b/comm/mailnews/test/data/smime/Eve.p12
diff --git a/comm/mailnews/test/data/smime/README.md b/comm/mailnews/test/data/smime/README.md
new file mode 100644
index 0000000000..90e46effd4
--- /dev/null
+++ b/comm/mailnews/test/data/smime/README.md
@@ -0,0 +1,23 @@
+S/MIME test certificates and messages
+=====================================
+
+This directory contains certificates and S/MIME test messages, which are
+generated by building NSS and executing a subset of the NSS test suite.
+
+The certificates will expire on the date listed in file expiration.txt
+
+The certificates must be refreshed around the expiration date.
+To do so, run the generate.sh script.
+
+Alternatively, join the #nss IRC channel and ask a member of the NSS
+team to execute the NSS test suite, and give you a copy of the contents
+of this directory:
+  tests_results/security/localhost.1/sharedb/smime/tb/
+
+(You only need the files having extensions .eml or .p12 or .pem .)
+
+The generate.sh script will automatically call local-gen.sh script,
+which generates additional test data, based on the updated NSS data.
+
+You may call local-gen.sh independently, if necessary, e.g. when adding
+new local tests.
diff --git a/comm/mailnews/test/data/smime/TestCA.pem b/comm/mailnews/test/data/smime/TestCA.pem
new file mode 100644
index 0000000000..0e9f065d6e
--- /dev/null
+++ b/comm/mailnews/test/data/smime/TestCA.pem
@@ -0,0 +1,21 @@
+-----BEGIN CERTIFICATE-----
+MIIDdTCCAl2gAwIBAgIBATANBgkqhkiG9w0BAQsFADBkMQswCQYDVQQGEwJVUzET
+MBEGA1UECBMKQ2FsaWZvcm5pYTEWMBQGA1UEBxMNTW91bnRhaW4gVmlldzESMBAG
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+CYk4ci1K5MuprqE6kBKKP8cGYL5ZqA4PPIHxlCgU2JR9G8NVn7Nw3Xb6ZTqRWTSn
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+q+q0haYFPt9MTGpvwA9JBoElS9I4XxJHbthlsCizas9UJfue37RIR5LRXA8zudRU
+Rwo8QS6MTgppRvorz2kvABRmkXiYk3Vn/g==
+-----END CERTIFICATE-----
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart
new file mode 100644
index 0000000000..d5215872b3
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart
@@ -0,0 +1,54 @@
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-1; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAA
+oIIDYjCCA14wggJGoAMCAQICAR4wDQYJKoZIhvcNAQELBQAwZDELMAkGA1UEBhMC
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+xieMAAAAAAAA
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.bad.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.bad.eml
new file mode 100644
index 0000000000..200c40916b
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.bad.eml
@@ -0,0 +1,59 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: BAD clear-signed sig.SHA1
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-1; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAA
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.eml
new file mode 100644
index 0000000000..49c7722d29
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.eml
@@ -0,0 +1,59 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA1
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-1; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAA
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.env b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.env
new file mode 100644
index 0000000000..7ae46f6c8a
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.env
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.env.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.env.eml
new file mode 100644
index 0000000000..9fc5639e62
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.env.eml
@@ -0,0 +1,84 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: clear-signed then enveloped sig.SHA1
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.mismatch-econtent b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.mismatch-econtent
new file mode 100644
index 0000000000..861f10e1e9
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.mismatch-econtent
@@ -0,0 +1,55 @@
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-1; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.mismatch-econtent.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.mismatch-econtent.eml
new file mode 100644
index 0000000000..bc85350c5c
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA1.multipart.mismatch-econtent.eml
@@ -0,0 +1,61 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: BAD mismatch-econtent sig.SHA1
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-1; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+e9uhSUBVTeVrORDGqQAVtDCSAAAAAAAA
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart
new file mode 100644
index 0000000000..9f52ddd580
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart
@@ -0,0 +1,54 @@
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgEFADCABgkqhkiG9w0B
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+MdQvFJGcfqtP6IzDgIMdg4Tw6IH2Gj0AAAAAAAA=
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.bad.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.bad.eml
new file mode 100644
index 0000000000..ae989dee6e
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.bad.eml
@@ -0,0 +1,60 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: BAD clear-signed sig.SHA256
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgEFADCABgkqhkiG9w0B
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+6k/oDIAAAAAAAAA=
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.eml
new file mode 100644
index 0000000000..c3c2ed9067
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.eml
@@ -0,0 +1,60 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA256
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgEFADCABgkqhkiG9w0B
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+6k/oDIAAAAAAAAA=
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.env b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.env
new file mode 100644
index 0000000000..d2bb1400b1
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.env
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.env.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.env.eml
new file mode 100644
index 0000000000..3bf13bb6d7
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.env.eml
@@ -0,0 +1,85 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: clear-signed then enveloped sig.SHA256
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
+MIAGCSqGSIb3DQEHA6CAMIACAQAxggGFMIIBgQIBADBpMGQxCzAJBgNVBAYTAlVT
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+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.mismatch-econtent b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.mismatch-econtent
new file mode 100644
index 0000000000..fbcfc22aeb
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.mismatch-econtent
@@ -0,0 +1,56 @@
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+fDoI7erSDAkAAAAAAAA=
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.mismatch-econtent.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.mismatch-econtent.eml
new file mode 100644
index 0000000000..6c6477a64c
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA256.multipart.mismatch-econtent.eml
@@ -0,0 +1,61 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: BAD mismatch-econtent sig.SHA256
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart
new file mode 100644
index 0000000000..5a1a1c2fdc
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart
@@ -0,0 +1,54 @@
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-384; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.bad.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.bad.eml
new file mode 100644
index 0000000000..1423fa9482
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.bad.eml
@@ -0,0 +1,60 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: BAD clear-signed sig.SHA384
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-384; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.eml
new file mode 100644
index 0000000000..a81560e276
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.eml
@@ -0,0 +1,60 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA384
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-384; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.env b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.env
new file mode 100644
index 0000000000..07f2160fba
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.env
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.env.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.env.eml
new file mode 100644
index 0000000000..8151234896
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.env.eml
@@ -0,0 +1,85 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: clear-signed then enveloped sig.SHA384
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.mismatch-econtent b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.mismatch-econtent
new file mode 100644
index 0000000000..827bb480c4
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.mismatch-econtent
@@ -0,0 +1,56 @@
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-384; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+Cg47Smcnd1EvG/BD0ZVF17bT2KC7rwF0AAAAAAAA
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.mismatch-econtent.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.mismatch-econtent.eml
new file mode 100644
index 0000000000..6772b1bbbe
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA384.multipart.mismatch-econtent.eml
@@ -0,0 +1,62 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: BAD mismatch-econtent sig.SHA384
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-384; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+YuZE1YxxAAAAAAAA
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart
new file mode 100644
index 0000000000..1960da58a8
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart
@@ -0,0 +1,55 @@
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+oLOutbnYBQAAAAAAAA==
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.bad.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.bad.eml
new file mode 100644
index 0000000000..c5ec8af01e
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.bad.eml
@@ -0,0 +1,60 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: BAD clear-signed sig.SHA512
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.eml
new file mode 100644
index 0000000000..2115292414
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.eml
@@ -0,0 +1,60 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA512
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.env b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.env
new file mode 100644
index 0000000000..2f09f19f96
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.env
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.env.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.env.eml
new file mode 100644
index 0000000000..32612a28ca
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.env.eml
@@ -0,0 +1,86 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: clear-signed then enveloped sig.SHA512
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
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+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.mismatch-econtent b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.mismatch-econtent
new file mode 100644
index 0000000000..8c4c3741c6
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.mismatch-econtent
@@ -0,0 +1,56 @@
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+MqxMGaXiLOqxz26zeedkvXI/ZyNeN8zBU9Zo0djCEfCE4GgDw+Kz/wAAAAAAAA==
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.mismatch-econtent.eml b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.mismatch-econtent.eml
new file mode 100644
index 0000000000..36e95acc06
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.dsig.SHA512.multipart.mismatch-econtent.eml
@@ -0,0 +1,62 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: BAD mismatch-econtent sig.SHA512
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a FAKE message NOT from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgMFADCABgkqhkiG9w0B
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+zbNgtMrWvXSl2GL0T48yDpbOYtS4dgAAAAAAAA==
+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.env.dsig.SHA1.multipart.dave.sig.SHA1.opaque.eml b/comm/mailnews/test/data/smime/alice.env.dsig.SHA1.multipart.dave.sig.SHA1.opaque.eml
new file mode 100644
index 0000000000..db24e18da0
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.dsig.SHA1.multipart.dave.sig.SHA1.opaque.eml
@@ -0,0 +1,128 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: enveloped then clear-signed sig.SHA1 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.env.dsig.SHA1.multipart.eml b/comm/mailnews/test/data/smime/alice.env.dsig.SHA1.multipart.eml
new file mode 100644
index 0000000000..4358503045
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.dsig.SHA1.multipart.eml
@@ -0,0 +1,75 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: enveloped then clear-signed sig.SHA1
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-1; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.env.dsig.SHA256.multipart.dave.sig.SHA256.opaque.eml b/comm/mailnews/test/data/smime/alice.env.dsig.SHA256.multipart.dave.sig.SHA256.opaque.eml
new file mode 100644
index 0000000000..980c55df08
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.dsig.SHA256.multipart.dave.sig.SHA256.opaque.eml
@@ -0,0 +1,129 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: enveloped then clear-signed sig.SHA256 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.env.dsig.SHA256.multipart.eml b/comm/mailnews/test/data/smime/alice.env.dsig.SHA256.multipart.eml
new file mode 100644
index 0000000000..58af108c00
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.dsig.SHA256.multipart.eml
@@ -0,0 +1,76 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: enveloped then clear-signed sig.SHA256
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.env.dsig.SHA384.multipart.dave.sig.SHA384.opaque.eml b/comm/mailnews/test/data/smime/alice.env.dsig.SHA384.multipart.dave.sig.SHA384.opaque.eml
new file mode 100644
index 0000000000..90705d69e8
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.dsig.SHA384.multipart.dave.sig.SHA384.opaque.eml
@@ -0,0 +1,130 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: enveloped then clear-signed sig.SHA384 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.env.dsig.SHA384.multipart.eml b/comm/mailnews/test/data/smime/alice.env.dsig.SHA384.multipart.eml
new file mode 100644
index 0000000000..e8c28de2cd
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.dsig.SHA384.multipart.eml
@@ -0,0 +1,76 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: enveloped then clear-signed sig.SHA384
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-384; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.env.dsig.SHA512.multipart.dave.sig.SHA512.opaque.eml b/comm/mailnews/test/data/smime/alice.env.dsig.SHA512.multipart.dave.sig.SHA512.opaque.eml
new file mode 100644
index 0000000000..8396145575
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.dsig.SHA512.multipart.dave.sig.SHA512.opaque.eml
@@ -0,0 +1,131 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: enveloped then clear-signed sig.SHA512 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.env.dsig.SHA512.multipart.eml b/comm/mailnews/test/data/smime/alice.env.dsig.SHA512.multipart.eml
new file mode 100644
index 0000000000..7eab13caa9
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.dsig.SHA512.multipart.eml
@@ -0,0 +1,76 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: enveloped then clear-signed sig.SHA512
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.env.eml b/comm/mailnews/test/data/smime/alice.env.eml
new file mode 100644
index 0000000000..d6ff3aa37c
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.eml
@@ -0,0 +1,26 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: enveloped 
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.env.sig.SHA1.opaque.dave.sig.SHA1.opaque.eml b/comm/mailnews/test/data/smime/alice.env.sig.SHA1.opaque.dave.sig.SHA1.opaque.eml
new file mode 100644
index 0000000000..295500f2ab
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.sig.SHA1.opaque.dave.sig.SHA1.opaque.eml
@@ -0,0 +1,131 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: enveloped then opaque-signed sig.SHA1 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.env.sig.SHA1.opaque.eml b/comm/mailnews/test/data/smime/alice.env.sig.SHA1.opaque.eml
new file mode 100644
index 0000000000..ddf0eb3d3c
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.sig.SHA1.opaque.eml
@@ -0,0 +1,70 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: enveloped then opaque-signed sig.SHA1
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.env.sig.SHA256.opaque.dave.sig.SHA256.opaque.eml b/comm/mailnews/test/data/smime/alice.env.sig.SHA256.opaque.dave.sig.SHA256.opaque.eml
new file mode 100644
index 0000000000..3835411fdd
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.sig.SHA256.opaque.dave.sig.SHA256.opaque.eml
@@ -0,0 +1,132 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: enveloped then opaque-signed sig.SHA256 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.env.sig.SHA256.opaque.eml b/comm/mailnews/test/data/smime/alice.env.sig.SHA256.opaque.eml
new file mode 100644
index 0000000000..d617329d23
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.sig.SHA256.opaque.eml
@@ -0,0 +1,71 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: enveloped then opaque-signed sig.SHA256
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.env.sig.SHA384.opaque.dave.sig.SHA384.opaque.eml b/comm/mailnews/test/data/smime/alice.env.sig.SHA384.opaque.dave.sig.SHA384.opaque.eml
new file mode 100644
index 0000000000..38ba154842
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.sig.SHA384.opaque.dave.sig.SHA384.opaque.eml
@@ -0,0 +1,132 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: enveloped then opaque-signed sig.SHA384 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.env.sig.SHA384.opaque.eml b/comm/mailnews/test/data/smime/alice.env.sig.SHA384.opaque.eml
new file mode 100644
index 0000000000..748a76eaf9
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.sig.SHA384.opaque.eml
@@ -0,0 +1,71 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: enveloped then opaque-signed sig.SHA384
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
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diff --git a/comm/mailnews/test/data/smime/alice.env.sig.SHA512.opaque.dave.sig.SHA512.opaque.eml b/comm/mailnews/test/data/smime/alice.env.sig.SHA512.opaque.dave.sig.SHA512.opaque.eml
new file mode 100644
index 0000000000..821a48aaa4
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.sig.SHA512.opaque.dave.sig.SHA512.opaque.eml
@@ -0,0 +1,133 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: enveloped then opaque-signed sig.SHA512 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.env.sig.SHA512.opaque.eml b/comm/mailnews/test/data/smime/alice.env.sig.SHA512.opaque.eml
new file mode 100644
index 0000000000..472aeca9e8
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.env.sig.SHA512.opaque.eml
@@ -0,0 +1,72 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: enveloped then opaque-signed sig.SHA512
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.future.dsig.SHA256.multipart.eml b/comm/mailnews/test/data/smime/alice.future.dsig.SHA256.multipart.eml
new file mode 100644
index 0000000000..c2096e561c
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.future.dsig.SHA256.multipart.eml
@@ -0,0 +1,60 @@
+MIME-Version: 1.0
+Date: Wed, 22 Nov 2023 02:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA256
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
diff --git a/comm/mailnews/test/data/smime/alice.mime b/comm/mailnews/test/data/smime/alice.mime
new file mode 100644
index 0000000000..ccbbc92e15
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.mime
@@ -0,0 +1,5 @@
+Content-Type: text/plain; charset=utf-8; format=flowed
+Content-Transfer-Encoding: quoted-printable
+Content-Language: en-US
+
+This is a test message from Alice to Bob.
diff --git a/comm/mailnews/test/data/smime/alice.mime.dsig.SHA1 b/comm/mailnews/test/data/smime/alice.mime.dsig.SHA1
new file mode 100644
index 0000000000..e9dd941c89
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.mime.dsig.SHA1
diff --git a/comm/mailnews/test/data/smime/alice.mime.dsig.SHA256 b/comm/mailnews/test/data/smime/alice.mime.dsig.SHA256
new file mode 100644
index 0000000000..3643ef3f35
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.mime.dsig.SHA256
diff --git a/comm/mailnews/test/data/smime/alice.mime.dsig.SHA384 b/comm/mailnews/test/data/smime/alice.mime.dsig.SHA384
new file mode 100644
index 0000000000..e93f04bdc7
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.mime.dsig.SHA384
diff --git a/comm/mailnews/test/data/smime/alice.mime.dsig.SHA512 b/comm/mailnews/test/data/smime/alice.mime.dsig.SHA512
new file mode 100644
index 0000000000..09f1bb8654
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.mime.dsig.SHA512
diff --git a/comm/mailnews/test/data/smime/alice.mime.env b/comm/mailnews/test/data/smime/alice.mime.env
new file mode 100644
index 0000000000..bca6133360
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.mime.env
diff --git a/comm/mailnews/test/data/smime/alice.plain.dsig.SHA1.multipart.dave.dsig.SHA1.multipart.eml b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA1.multipart.dave.dsig.SHA1.multipart.eml
new file mode 100644
index 0000000000..c09006f695
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA1.multipart.dave.dsig.SHA1.multipart.eml
@@ -0,0 +1,108 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA1 then clear-signed signed by dave
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-1; boundary="------------ms010205070902020502030809"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms010205070902020502030809
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-1; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+9gn/QVb12HnVoWhUSKtQe9uhSUBVTeVrORDGqQAVtDCSAAAAAAAA
+--------------ms030903020902020502030404--
+
+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+
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+--------------ms010205070902020502030809--
+
+
diff --git a/comm/mailnews/test/data/smime/alice.plain.dsig.SHA1.multipart.dave.sig.SHA1.opaque.eml b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA1.multipart.dave.sig.SHA1.opaque.eml
new file mode 100644
index 0000000000..dddae44229
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA1.multipart.dave.sig.SHA1.opaque.eml
@@ -0,0 +1,107 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA1 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.plain.dsig.SHA256.multipart.dave.dsig.SHA256.multipart.eml b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA256.multipart.dave.dsig.SHA256.multipart.eml
new file mode 100644
index 0000000000..f884d97d22
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA256.multipart.dave.dsig.SHA256.multipart.eml
@@ -0,0 +1,110 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA256 then clear-signed signed by dave
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms010205070902020502030809"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms010205070902020502030809
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+
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+--------------ms010205070902020502030809--
+
+
diff --git a/comm/mailnews/test/data/smime/alice.plain.dsig.SHA256.multipart.dave.sig.SHA256.opaque.eml b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA256.multipart.dave.sig.SHA256.opaque.eml
new file mode 100644
index 0000000000..2e7b02fd5c
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA256.multipart.dave.sig.SHA256.opaque.eml
@@ -0,0 +1,108 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA256 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.plain.dsig.SHA384.multipart.dave.dsig.SHA384.multipart.eml b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA384.multipart.dave.dsig.SHA384.multipart.eml
new file mode 100644
index 0000000000..ce76b53615
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA384.multipart.dave.dsig.SHA384.multipart.eml
@@ -0,0 +1,110 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA384 then clear-signed signed by dave
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-384; boundary="------------ms010205070902020502030809"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms010205070902020502030809
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-384; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+
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+--------------ms010205070902020502030809--
+
+
diff --git a/comm/mailnews/test/data/smime/alice.plain.dsig.SHA384.multipart.dave.sig.SHA384.opaque.eml b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA384.multipart.dave.sig.SHA384.opaque.eml
new file mode 100644
index 0000000000..6bf0dd9c1a
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA384.multipart.dave.sig.SHA384.opaque.eml
@@ -0,0 +1,109 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA384 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.plain.dsig.SHA512.multipart.dave.dsig.SHA512.multipart.eml b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA512.multipart.dave.dsig.SHA512.multipart.eml
new file mode 100644
index 0000000000..f642393b9d
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA512.multipart.dave.dsig.SHA512.multipart.eml
@@ -0,0 +1,110 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA512 then clear-signed signed by dave
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms010205070902020502030809"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms010205070902020502030809
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms030903020902020502030404"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms030903020902020502030404
+Content-Type: text/plain
+
+This is a test message from Alice to Bob.
+
+--------------ms030903020902020502030404
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms030903020902020502030404--
+
+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+--------------ms010205070902020502030809--
+
+
diff --git a/comm/mailnews/test/data/smime/alice.plain.dsig.SHA512.multipart.dave.sig.SHA512.opaque.eml b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA512.multipart.dave.sig.SHA512.opaque.eml
new file mode 100644
index 0000000000..5cf6af5917
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.dsig.SHA512.multipart.dave.sig.SHA512.opaque.eml
@@ -0,0 +1,110 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: clear-signed sig.SHA512 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.plain.sig.SHA1.opaque.dave.dsig.SHA1.multipart.eml b/comm/mailnews/test/data/smime/alice.plain.sig.SHA1.opaque.dave.dsig.SHA1.multipart.eml
new file mode 100644
index 0000000000..7cd2374913
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.sig.SHA1.opaque.dave.dsig.SHA1.multipart.eml
@@ -0,0 +1,99 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA1 then clear-signed signed by dave
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-1; boundary="------------ms010205070902020502030809"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+
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+--------------ms010205070902020502030809--
+
+
diff --git a/comm/mailnews/test/data/smime/alice.plain.sig.SHA1.opaque.dave.sig.SHA1.opaque.eml b/comm/mailnews/test/data/smime/alice.plain.sig.SHA1.opaque.dave.sig.SHA1.opaque.eml
new file mode 100644
index 0000000000..e8453479e3
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.sig.SHA1.opaque.dave.sig.SHA1.opaque.eml
@@ -0,0 +1,102 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA1 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.plain.sig.SHA256.opaque.dave.dsig.SHA256.multipart.eml b/comm/mailnews/test/data/smime/alice.plain.sig.SHA256.opaque.dave.dsig.SHA256.multipart.eml
new file mode 100644
index 0000000000..78fd4338f0
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.sig.SHA256.opaque.dave.dsig.SHA256.multipart.eml
@@ -0,0 +1,100 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA256 then clear-signed signed by dave
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-256; boundary="------------ms010205070902020502030809"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
+
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+--------------ms010205070902020502030809--
+
+
diff --git a/comm/mailnews/test/data/smime/alice.plain.sig.SHA256.opaque.dave.sig.SHA256.opaque.eml b/comm/mailnews/test/data/smime/alice.plain.sig.SHA256.opaque.dave.sig.SHA256.opaque.eml
new file mode 100644
index 0000000000..75977ae5d6
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.sig.SHA256.opaque.dave.sig.SHA256.opaque.eml
@@ -0,0 +1,103 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA256 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
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+
diff --git a/comm/mailnews/test/data/smime/alice.plain.sig.SHA384.opaque.dave.dsig.SHA384.multipart.eml b/comm/mailnews/test/data/smime/alice.plain.sig.SHA384.opaque.dave.dsig.SHA384.multipart.eml
new file mode 100644
index 0000000000..f7bba58170
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.sig.SHA384.opaque.dave.dsig.SHA384.multipart.eml
@@ -0,0 +1,101 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA384 then clear-signed signed by dave
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-384; boundary="------------ms010205070902020502030809"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+
+
diff --git a/comm/mailnews/test/data/smime/alice.plain.sig.SHA384.opaque.dave.sig.SHA384.opaque.eml b/comm/mailnews/test/data/smime/alice.plain.sig.SHA384.opaque.dave.sig.SHA384.opaque.eml
new file mode 100644
index 0000000000..2bca810f96
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.sig.SHA384.opaque.dave.sig.SHA384.opaque.eml
@@ -0,0 +1,103 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA384 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
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diff --git a/comm/mailnews/test/data/smime/alice.plain.sig.SHA512.opaque.dave.dsig.SHA512.multipart.eml b/comm/mailnews/test/data/smime/alice.plain.sig.SHA512.opaque.dave.dsig.SHA512.multipart.eml
new file mode 100644
index 0000000000..c213faa60a
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.sig.SHA512.opaque.dave.dsig.SHA512.multipart.eml
@@ -0,0 +1,101 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA512 then clear-signed signed by dave
+Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms010205070902020502030809"
+
+This is a cryptographically signed message in MIME format.
+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
+--------------ms010205070902020502030809
+Content-Type: application/pkcs7-signature; name=smime.p7s
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7s
+Content-Description: S/MIME Cryptographic Signature
+
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+
+
diff --git a/comm/mailnews/test/data/smime/alice.plain.sig.SHA512.opaque.dave.sig.SHA512.opaque.eml b/comm/mailnews/test/data/smime/alice.plain.sig.SHA512.opaque.dave.sig.SHA512.opaque.eml
new file mode 100644
index 0000000000..f91a7240b8
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.plain.sig.SHA512.opaque.dave.sig.SHA512.opaque.eml
@@ -0,0 +1,104 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Dave@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA512 then opaque signed by dave
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
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+
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque b/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque
new file mode 100644
index 0000000000..a6a2f98d04
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque
@@ -0,0 +1,42 @@
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque.eml b/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque.eml
new file mode 100644
index 0000000000..8dbc85328a
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque.eml
@@ -0,0 +1,49 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA1
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque.env b/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque.env
new file mode 100644
index 0000000000..2a0837b0df
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque.env
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque.env.eml b/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque.env.eml
new file mode 100644
index 0000000000..d9ab8a516b
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA1.opaque.env.eml
@@ -0,0 +1,77 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: opaque-signed then enveloped sig.SHA1
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque b/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque
new file mode 100644
index 0000000000..6743858212
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque
@@ -0,0 +1,43 @@
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque.eml b/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque.eml
new file mode 100644
index 0000000000..2d250d71b8
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque.eml
@@ -0,0 +1,49 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA256
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque.env b/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque.env
new file mode 100644
index 0000000000..8678aa4990
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque.env
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque.env.eml b/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque.env.eml
new file mode 100644
index 0000000000..fb141a23a1
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA256.opaque.env.eml
@@ -0,0 +1,77 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: opaque-signed then enveloped sig.SHA256
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque b/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque
new file mode 100644
index 0000000000..ad985e9fe1
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque
@@ -0,0 +1,43 @@
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque.eml b/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque.eml
new file mode 100644
index 0000000000..12bda4ac0e
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque.eml
@@ -0,0 +1,50 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA384
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque.env b/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque.env
new file mode 100644
index 0000000000..fafb42fdfb
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque.env
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque.env.eml b/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque.env.eml
new file mode 100644
index 0000000000..0168f70662
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA384.opaque.env.eml
@@ -0,0 +1,78 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: opaque-signed then enveloped sig.SHA384
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
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+
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque b/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque
new file mode 100644
index 0000000000..f5be55e031
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque
@@ -0,0 +1,43 @@
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque.eml b/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque.eml
new file mode 100644
index 0000000000..ee2a880163
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque.eml
@@ -0,0 +1,50 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: opaque-signed sig.SHA512
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=signed-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Cryptographic Signature
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque.env b/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque.env
new file mode 100644
index 0000000000..b3ceab836d
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque.env
diff --git a/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque.env.eml b/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque.env.eml
new file mode 100644
index 0000000000..fce61249d0
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.sig.SHA512.opaque.env.eml
@@ -0,0 +1,78 @@
+MIME-Version: 1.0
+Date: Tue, 21 Nov 2023 20:50:06 +0000
+From: Alice@example.com
+To: Bob@example.com
+Subject: opaque-signed then enveloped sig.SHA512
+Content-Type: application/pkcs7-mime; name=smime.p7m;
+    smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+Content-Disposition: attachment; filename=smime.p7m
+Content-Description: S/MIME Encrypted Message
+
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+
diff --git a/comm/mailnews/test/data/smime/alice.textplain b/comm/mailnews/test/data/smime/alice.textplain
new file mode 100644
index 0000000000..ef8b8f84ec
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.textplain
@@ -0,0 +1,3 @@
+Content-Type: text/plain
+
+This is a test message from Alice to Bob.
diff --git a/comm/mailnews/test/data/smime/alice.textplain.sig.SHA1 b/comm/mailnews/test/data/smime/alice.textplain.sig.SHA1
new file mode 100644
index 0000000000..abf83fb632
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.textplain.sig.SHA1
diff --git a/comm/mailnews/test/data/smime/alice.textplain.sig.SHA256 b/comm/mailnews/test/data/smime/alice.textplain.sig.SHA256
new file mode 100644
index 0000000000..78e35b5dea
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.textplain.sig.SHA256
diff --git a/comm/mailnews/test/data/smime/alice.textplain.sig.SHA384 b/comm/mailnews/test/data/smime/alice.textplain.sig.SHA384
new file mode 100644
index 0000000000..f887be3a11
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.textplain.sig.SHA384
diff --git a/comm/mailnews/test/data/smime/alice.textplain.sig.SHA512 b/comm/mailnews/test/data/smime/alice.textplain.sig.SHA512
new file mode 100644
index 0000000000..114a61db50
--- /dev/null
+++ b/comm/mailnews/test/data/smime/alice.textplain.sig.SHA512
diff --git a/comm/mailnews/test/data/smime/expiration.txt b/comm/mailnews/test/data/smime/expiration.txt
new file mode 100644
index 0000000000..18de5dd6f2
--- /dev/null
+++ b/comm/mailnews/test/data/smime/expiration.txt
@@ -0,0 +1 @@
+Tue Nov 21 20:50:36 2028
diff --git a/comm/mailnews/test/data/smime/generate.sh b/comm/mailnews/test/data/smime/generate.sh
new file mode 100755
index 0000000000..d2625b9f39
--- /dev/null
+++ b/comm/mailnews/test/data/smime/generate.sh
@@ -0,0 +1,79 @@
+#!/bin/bash
+
+set -e
+
+# This script creates updated data for automated S/MIME tests.
+# It will do a local build of NSS, execute parts of the NSS test suite,
+# and copy data created by it to the local source tree.
+
+if ! test -e generate.sh || ! test -e local-gen.sh
+then
+  echo "you must run this script from inside the directory that contains generate.sh and local-gen.sh"
+  exit
+fi
+
+mkdir nssbuild
+pushd nssbuild
+
+cp -riv ../../../../../../security/nss nss
+cp -riv ../../../../../../nsprpub nspr
+
+export USE_64=1
+cd nss
+make nss_build_all
+
+export NSS_CYCLES=sharedb
+export NSS_TESTS=smime
+cd tests
+HOST=localhost DOMSUF=localdomain ./all.sh
+
+popd
+cp -v nssbuild/tests_results/security/localhost.1/sharedb/smime/tb/*.eml .
+cp -v nssbuild/tests_results/security/localhost.1/sharedb/smime/tb/*.p12 .
+cp -v nssbuild/tests_results/security/localhost.1/sharedb/smime/tb/*.pem .
+
+CWD=$(pwd)
+
+EXPIRATION_INFO_FILE="$CWD/expiration.txt"
+ALICE_DIR="$CWD/nssbuild/tests_results/security/localhost.1/sharedb/alicedir"
+
+export DIST="$CWD/nssbuild/dist/"
+
+pushd nssbuild/nss/tests/common
+OBJDIR=$(make objdir_name)
+export OBJDIR
+popd
+
+# PATH logic copied from nss/tests/common/init.sh
+if [ "${OS_ARCH}" = "WINNT" ] && [ "$OS_NAME" != "CYGWIN_NT" ] && [ "$OS_NAME" != "MINGW32_NT" ]; then
+    PATH=.\;${DIST}/${OBJDIR}/bin\;${DIST}/${OBJDIR}/lib\;$PATH
+    PATH=$(perl ../path_uniq -d ';' "$PATH")
+elif [ "${OS_ARCH}" = "Android" ]; then
+    # android doesn't have perl, skip the uniq step
+    PATH=.:${DIST}/${OBJDIR}/bin:${DIST}/${OBJDIR}/lib:$PATH
+else
+    PATH=.:${DIST}/${OBJDIR}/bin:${DIST}/${OBJDIR}/lib:/bin:/usr/bin:$PATH
+    # added /bin and /usr/bin in the beginning so a local perl will
+    # be used
+    PATH=$(perl nssbuild/nss/tests/path_uniq -d ':' "$PATH")
+fi
+
+export PATH
+export LD_LIBRARY_PATH=${DIST}/${OBJDIR}/lib:$LD_LIBRARY_PATH
+export SHLIB_PATH=${DIST}/${OBJDIR}/lib:$SHLIB_PATH
+export LIBPATH=${DIST}/${OBJDIR}/lib:$LIBPATH
+export DYLD_LIBRARY_PATH=${DIST}/${OBJDIR}/lib:$DYLD_LIBRARY_PATH
+
+certutil -d "${ALICE_DIR}" -L -n Alice |grep -i "Not After" | \
+  sed 's/^.*: //' > "${EXPIRATION_INFO_FILE}"
+
+# exporting DYLD_LIBRARY_PATH to a subprocess doesn't work on recent OSX
+export NSS_LIB_PATH=${DIST}/${OBJDIR}/lib
+
+# Now refresh Thunderbird's local test data that is based on the NSS
+# test suite data.
+./local-gen.sh
+
+echo "Done. Will remove the NSS build/test tree in 20 seconds."
+sleep 20
+rm -rf nssbuild
diff --git a/comm/mailnews/test/data/smime/local-gen.sh b/comm/mailnews/test/data/smime/local-gen.sh
new file mode 100755
index 0000000000..c74b31e73a
--- /dev/null
+++ b/comm/mailnews/test/data/smime/local-gen.sh
@@ -0,0 +1,97 @@
+#!/bin/bash
+
+set -e
+
+# This script creates additional S/MIME test files.
+# It's called automatically by generate.sh.
+# However, it can also be called directly, if the test data from NSS
+# is still sufficiently fresh, and only the local test files need to
+# be updated, e.g. when adding new tests.
+
+if [ -n "$NSS_LIB_PATH" ]
+then
+  export LD_LIBRARY_PATH=${NSS_LIB_PATH}:$LD_LIBRARY_PATH
+  export SHLIB_PATH=${NSS_LIB_PATH}:$SHLIB_PATH
+  export LIBPATH=${NSS_LIB_PATH}:$LIBPATH
+  export DYLD_LIBRARY_PATH=${NSS_LIB_PATH}:$DYLD_LIBRARY_PATH
+fi
+
+if ! test -e generate.sh || ! test -e local-gen.sh
+then
+  echo "you must run this script from inside the directory that contains local-gen.sh and generate.sh"
+  exit
+fi
+
+if ! hash certutil || ! hash pk12util || ! hash atob || ! hash btoa
+then
+  echo "Required NSS utilities cannot be executed. Add \$OBJDIR/dist/bin of a local Thunderbird build to both the PATH and (platform specific) library path environment variable (e.g. LD_LIBRARY_PATH or DYLD_LIBRARY_PATH)."
+  exit
+fi
+
+MILLDIR="$(pwd)/../../../../mail/test/browser/smime/data"
+
+# When executing mozmill in the CI environment, the files from this
+# directory aren't available. Copy all files that mozmill requires to
+# the mozmill directory.
+cp -rv Bob.p12 TestCA.pem "$MILLDIR"
+
+TMPDIR="./tmp-local"
+mkdir $TMPDIR
+
+BOUNDARY="--------BOUNDARY"
+
+EMAILDATE=$(date --rfc-email --utc)
+
+MSGHEADER="MIME-Version: 1.0
+Date: ${EMAILDATE}
+From: Alice <alice@example.com>
+To: Bob <bob@example.com>
+Subject: a message
+Content-Type: multipart/alternative; boundary=\"${BOUNDARY}\"
+
+"
+
+ENVHEADER="Content-Type: application/pkcs7-mime; smime-type=enveloped-data
+Content-Transfer-Encoding: base64
+
+"
+
+certutil -d $TMPDIR -N --empty-password
+pk12util -d $TMPDIR -i Alice.p12 -W nss
+pk12util -d $TMPDIR -i Bob.p12 -W nss
+certutil -d $TMPDIR -M -n TestCA -t C,C,
+
+INPUT="Content-type: text/plain
+
+SECRET-TEXT the attacker wants to steal
+"
+echo "$INPUT" | cmsutil -d $TMPDIR -E -r bob@example.com | btoa > $TMPDIR/prey.b64
+
+INPUT="Content-type: text/html
+
+<pre>Please reply to this harmless looking message</pre><style>.moz-text-plain, .moz-quote-pre, fieldset {display: none;}</style>"
+echo "$INPUT" | cmsutil -d $TMPDIR -E -r bob@example.com | btoa > $TMPDIR/bait.b64
+
+MSG=$TMPDIR/msg.eml
+
+{
+  echo -n "$MSGHEADER"
+  echo "--$BOUNDARY"
+  echo -n "$ENVHEADER"
+  cat $TMPDIR/bait.b64
+  echo "--$BOUNDARY"
+  echo -n "$ENVHEADER"
+  cat $TMPDIR/prey.b64
+  echo "--$BOUNDARY"
+} > $MSG
+
+mv $MSG "$MILLDIR/multipart-alternative.eml"
+
+# Create a message with a mismatching message date (use a later time,
+# because the test certificates aren't valid at earlier times).
+
+GOOD_DATE=$(grep ^Date "alice.dsig.SHA256.multipart.eml" | sed 's/^Date: //')
+FUTURE_DATE=$(date --utc --rfc-email --date="${GOOD_DATE} + 6 hours")
+sed "s/^Date: .*$/Date: ${FUTURE_DATE}/" "alice.dsig.SHA256.multipart.eml" > "alice.future.dsig.SHA256.multipart.eml"
+
+rm -rf $TMPDIR