melib/attachments: add SMIME signature variant

3 files changed, 21 insertions, 12 deletions

diff --git a/melib/src/email/attachment_types.rs b/melib/src/email/attachment_types.rs
index 0dcf5dbb..74d4e1fb 100644
--- a/melib/src/email/attachment_types.rs
+++ b/melib/src/email/attachment_types.rs
@@ -198,6 +198,7 @@ pub enum ContentType {
     },
     MessageRfc822,
     PGPSignature,
+    CMSSignature,
     Other {
         tag: Vec<u8>,
         name: Option<String>,
@@ -275,6 +276,7 @@ impl PartialEq<&str> for ContentType {
                 "multipart/signed",
             ) => true,
             (ContentType::PGPSignature, "application/pgp-signature") => true,
+            (ContentType::CMSSignature, "application/pkcs7-signature") => true,
             (ContentType::MessageRfc822, "message/rfc822") => true,
             (ContentType::Other { tag, .. }, _) => {
                 other.eq_ignore_ascii_case(&String::from_utf8_lossy(&tag))
@@ -292,6 +294,7 @@ impl Display for ContentType {
             ContentType::Multipart { kind: k, .. } => k.fmt(f),
             ContentType::Other { ref tag, .. } => write!(f, "{}", String::from_utf8_lossy(tag)),
             ContentType::PGPSignature => write!(f, "application/pgp-signature"),
+            ContentType::CMSSignature => write!(f, "application/pkcs7-signature"),
             ContentType::MessageRfc822 => write!(f, "message/rfc822"),
             ContentType::OctetStream { .. } => write!(f, "application/octet-stream"),
         }
diff --git a/melib/src/email/attachments.rs b/melib/src/email/attachments.rs
index 6c6c4aa4..964183ba 100644
--- a/melib/src/email/attachments.rs
+++ b/melib/src/email/attachments.rs
@@ -202,6 +202,10 @@ impl AttachmentBuilder {
                     && cst.eq_ignore_ascii_case(b"pgp-signature")
                 {
                     self.content_type = ContentType::PGPSignature;
+                } else if ct.eq_ignore_ascii_case(b"application")
+                    && cst.eq_ignore_ascii_case(b"pkcs7-signature")
+                {
+                    self.content_type = ContentType::CMSSignature;
                 } else {
                     let mut name: Option<String> = None;
                     for (n, v) in params {
@@ -384,6 +388,7 @@ impl fmt::Display for Attachment {
                 }
             }
             ContentType::PGPSignature => write!(f, "pgp signature [{}]", self.mime_type()),
+            ContentType::CMSSignature => write!(f, "S/MIME signature [{}]", self.mime_type()),
             ContentType::OctetStream { .. } | ContentType::Other { .. } => {
                 if let Some(name) = self.filename() {
                     write!(
@@ -548,7 +553,7 @@ impl Attachment {
 
     fn get_text_recursive(&self, text: &mut Vec<u8>) {
         match self.content_type {
-            ContentType::Text { .. } | ContentType::PGPSignature => {
+            ContentType::Text { .. } | ContentType::PGPSignature | ContentType::CMSSignature => {
                 text.extend(decode(self, None));
             }
             ContentType::Multipart {
@@ -720,7 +725,7 @@ impl Attachment {
                     ret.push_str(&format!("Content-Type: {}\r\n\r\n", a.content_type));
                     ret.push_str(&String::from_utf8_lossy(a.body()));
                 }
-                ContentType::PGPSignature => {
+                ContentType::CMSSignature | ContentType::PGPSignature => {
                     ret.push_str(&format!("Content-Type: {}\r\n\r\n", a.content_type));
                     ret.push_str(&String::from_utf8_lossy(a.body()));
                 }
@@ -808,7 +813,7 @@ fn decode_rec_helper<'a, 'b>(a: &'a Attachment, filter: &mut Option<Filter<'b>>)
         ContentType::OctetStream { ref name } => {
             name.clone().unwrap_or_else(|| a.mime_type()).into_bytes()
         }
-        ContentType::PGPSignature => Vec::new(),
+        ContentType::CMSSignature | ContentType::PGPSignature => Vec::new(),
         ContentType::MessageRfc822 => {
             if a.content_disposition.kind.is_inline() {
                 let b = AttachmentBuilder::new(a.body()).build();
diff --git a/melib/src/email/pgp.rs b/melib/src/email/pgp.rs
index d3dd2ced..4f569053 100644
--- a/melib/src/email/pgp.rs
+++ b/melib/src/email/pgp.rs
@@ -20,7 +20,6 @@
  */
 
 /*! Verification of OpenPGP signatures */
-use crate::email::parser::BytesExt;
 use crate::email::{
     attachment_types::{ContentType, MultipartType},
     attachments::Attachment,
@@ -88,7 +87,7 @@ pub fn convert_attachment_to_rfc_spec(input: &[u8]) -> Vec<u8> {
     ret
 }
 
-pub fn verify_signature(a: &Attachment) -> Result<(Vec<u8>, &[u8])> {
+pub fn verify_signature(a: &Attachment) -> Result<(Vec<u8>, &Attachment)> {
     match a.content_type {
         ContentType::Multipart {
             kind: MultipartType::Signed,
@@ -107,7 +106,10 @@ pub fn verify_signature(a: &Attachment) -> Result<(Vec<u8>, &[u8])> {
             let signed_part: Vec<u8> = if let Some(v) = parts
                 .iter()
                 .zip(part_boundaries.iter())
-                .find(|(p, _)| p.content_type != ContentType::PGPSignature)
+                .find(|(p, _)| {
+                    p.content_type != ContentType::PGPSignature
+                        && p.content_type != ContentType::CMSSignature
+                })
                 .map(|(_, s)| convert_attachment_to_rfc_spec(s.display_bytes(a.body())))
             {
                 v
@@ -116,12 +118,11 @@ pub fn verify_signature(a: &Attachment) -> Result<(Vec<u8>, &[u8])> {
                     "multipart/signed attachment without a signed part".to_string(),
                 ));
             };
-            let signature = if let Some(sig) = parts
-                .iter()
-                .find(|s| s.content_type == ContentType::PGPSignature)
-                .map(|a| a.body())
-            {
-                sig.trim()
+            let signature = if let Some(sig) = parts.iter().find(|s| {
+                s.content_type == ContentType::PGPSignature
+                    || s.content_type == ContentType::CMSSignature
+            }) {
+                sig
             } else {
                 return Err(MeliError::new(
                     "multipart/signed attachment without a signature part".to_string(),