[evolution-data-server] Bug 792610 - [GPG] Consider alternate signer emails in sender address verification

[Milan Crha <mcrha src gnome org>]

commit 0b17843779ee1c80479c33de532d13ca3d9da425
Author: Milan Crha <mcrha redhat com>
Date:   Thu Jan 18 17:39:31 2018 +0100

    Bug 792610 - [GPG] Consider alternate signer emails in sender address verification

 src/camel/camel-cipher-context.h |   13 ++++++
 src/camel/camel-gpg-context.c    |   86 +++++++++++++++++++++++++++++++++++++-
 2 files changed, 97 insertions(+), 2 deletions(-)
---
diff --git a/src/camel/camel-cipher-context.h b/src/camel/camel-cipher-context.h
index 88783b2..28d712c 100644
--- a/src/camel/camel-cipher-context.h
+++ b/src/camel/camel-cipher-context.h
@@ -56,6 +56,19 @@
  **/
 #define CAMEL_CIPHER_CERT_INFO_PROPERTY_PHOTO_FILENAME "photo-filename"
 
+/**
+ * CAMEL_CIPHER_CERT_INFO_PROPERTY_SIGNERS_ALT_EMAILS:
+ *
+ * A string containing a list of email addresses of all signers
+ * including their alternative emails. Use camel_address_unformat()
+ * to break them back into separate addresses. This can be set
+ * only on the first signer of the first validity, even the addresses
+ * can belong to a different signer.
+ *
+ * Since: 3.28
+ **/
+#define CAMEL_CIPHER_CERT_INFO_PROPERTY_SIGNERS_ALT_EMAILS "signers-alt-emails"
+
 G_BEGIN_DECLS
 
 typedef gpointer (* CamelCipherCloneFunc) (gpointer value);
diff --git a/src/camel/camel-gpg-context.c b/src/camel/camel-gpg-context.c
index a84c27e..06dd7b1 100644
--- a/src/camel/camel-gpg-context.c
+++ b/src/camel/camel-gpg-context.c
@@ -1717,8 +1717,75 @@ camel_gpg_context_clone_photo_filename (gpointer ptr)
        return (gpointer) camel_pstring_strdup (ptr);
 }
 
+static CamelInternetAddress *
+gpg_ctx_extract_email_addresses_from_text (const gchar *text)
+{
+       CamelInternetAddress *signers_alt_emails = NULL;
+       const gchar *lt = NULL, *gt = NULL, *bs = NULL, *be = NULL;
+       gssize ii;
+
+       for (ii = 0; text && text[ii]; ii++) {
+               switch (text[ii]) {
+               case '<':
+                       lt = text + ii;
+                       gt = NULL;
+                       bs = NULL;
+                       be = NULL;
+                       break;
+               case '>':
+                       if (lt) {
+                               gt = text + ii;
+                               bs = NULL;
+                               be = NULL;
+                       }
+                       break;
+               case '[':
+                       if (lt && gt) {
+                               bs = text + ii;
+                               be = NULL;
+                       }
+                       break;
+               case ']':
+                       if (lt && gt && bs) {
+                               be = text + ii;
+                       }
+                       break;
+               case '\n':
+                       if (lt && lt < gt && gt < bs && bs < be) {
+                               gchar *email = g_strndup (lt + 1, gt - lt - 1);
+
+                               if (!signers_alt_emails)
+                                       signers_alt_emails = camel_internet_address_new ();
+
+                               camel_internet_address_add (signers_alt_emails, NULL, email);
+                               g_free (email);
+                       }
+                       lt = NULL;
+                       gt = NULL;
+                       bs = NULL;
+                       be = NULL;
+                       break;
+               default:
+                       break;
+               }
+       }
+
+       if (lt && lt < gt && gt < bs && bs < be) {
+               gchar *email = g_strndup (lt + 1, gt - lt - 1);
+
+               if (!signers_alt_emails)
+                       signers_alt_emails = camel_internet_address_new ();
+
+               camel_internet_address_add (signers_alt_emails, NULL, email);
+               g_free (email);
+       }
+
+       return signers_alt_emails;
+}
+
 static void
 add_signers (CamelCipherValidity *validity,
+            const gchar *diagnostics,
             const GString *signers,
             GHashTable *signers_keyid,
             const gchar *photos_filename)
@@ -1799,6 +1866,21 @@ add_signers (CamelCipherValidity *validity,
        if (photos)
                g_hash_table_destroy (photos);
        g_object_unref (address);
+
+       if (diagnostics && !g_queue_is_empty (&validity->sign.signers)) {
+               CamelInternetAddress *signers_alt_emails;
+
+               signers_alt_emails = gpg_ctx_extract_email_addresses_from_text (diagnostics);
+               if (signers_alt_emails && camel_address_length (CAMEL_ADDRESS (signers_alt_emails)) > 1) {
+                       gchar *addresses = camel_address_format (CAMEL_ADDRESS (signers_alt_emails));
+
+                       camel_cipher_validity_set_certinfo_property (validity, CAMEL_CIPHER_VALIDITY_SIGN, 0,
+                               CAMEL_CIPHER_CERT_INFO_PROPERTY_SIGNERS_ALT_EMAILS, addresses,
+                               g_free, (CamelCipherCloneFunc) g_strdup);
+               }
+
+               g_clear_object (&signers_alt_emails);
+       }
 }
 
 /* ********************************************************************** */
@@ -2276,7 +2358,7 @@ gpg_verify_sync (CamelCipherContext *context,
                validity->sign.status = CAMEL_CIPHER_VALIDITY_SIGN_BAD;
        }
 
-       add_signers (validity, gpg->signers, gpg->signers_keyid, gpg->photos_filename);
+       add_signers (validity, diagnostics, gpg->signers, gpg->signers_keyid, gpg->photos_filename);
 
        gpg_ctx_free (gpg);
 
@@ -2611,7 +2693,7 @@ gpg_decrypt_sync (CamelCipherContext *context,
                                valid->sign.status = CAMEL_CIPHER_VALIDITY_SIGN_BAD;
                        }
 
-                       add_signers (valid, gpg->signers, gpg->signers_keyid, gpg->photos_filename);
+                       add_signers (valid, gpg_ctx_get_diagnostics (gpg), gpg->signers, gpg->signers_keyid, 
gpg->photos_filename);
                }
        }