[PATCH 3/3] cli: crypto: S/MIME verification/decryption support

[Jani Nikula]

The notmuch-show flags --decrypt and --verify will now also process
S/MIME multiparts if encountered. Requires gmime-2.6 and gpgsm.

Based on work by Jameson Graef Rollins <jrollins at finestructure.net>.

---

id:1340995101-9616-2-git-send-email-jrollins at finestructure.net
---
 crypto.c         | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 notmuch-client.h |  7 +++++--
 2 files changed, 53 insertions(+), 2 deletions(-)

diff --git a/crypto.c b/crypto.c
index 8e58dcca4ee5..8944cc5d4bcd 100644
--- a/crypto.c
+++ b/crypto.c
@@ -45,6 +45,29 @@ create_gpg_context (notmuch_crypto_t *crypto)
     return gpgctx;
 }
 
+/* Create a PKCS7 context (GMime 2.6) */
+static notmuch_crypto_context_t *
+create_pkcs7_context (notmuch_crypto_t *crypto)
+{
+    notmuch_crypto_context_t *pkcs7ctx;
+
+    if (crypto->pkcs7ctx)
+	return crypto->pkcs7ctx;
+
+    /* TODO: GMimePasswordRequestFunc */
+    pkcs7ctx = g_mime_pkcs7_context_new (NULL);
+    if (! pkcs7ctx) {
+	fprintf (stderr, "Failed to construct pkcs7 context.\n");
+	return NULL;
+    }
+    crypto->pkcs7ctx = pkcs7ctx;
+
+    g_mime_pkcs7_context_set_always_trust ((GMimePkcs7Context *) pkcs7ctx,
+					   FALSE);
+
+    return pkcs7ctx;
+}
+
 #else /* GMIME_ATLEAST_26 */
 
 /* Create a GPG context (GMime 2.4) */
@@ -72,6 +95,14 @@ create_gpg_context (notmuch_crypto_t *crypto)
     return gpgctx;
 }
 
+/* Create a PKCS7 context (GMime 2.4) */
+static notmuch_crypto_context_t *
+create_pkcs7_context (notmuch_crypto_t *crypto)
+{
+    fprintf (stderr, "pkcs7 is not supported in gmime 2.4.\n");
+    return NULL;
+}
+
 #endif /* GMIME_ATLEAST_26 */
 
 static struct {
@@ -86,6 +117,18 @@ static struct {
 	.protocol = "application/pgp-encrypted",
 	.get_context = create_gpg_context,
     },
+    {
+	.protocol = "application/pkcs7-signature",
+	.get_context = create_pkcs7_context,
+    },
+    {
+	.protocol = "application/x-pkcs7-signature",
+	.get_context = create_pkcs7_context,
+    },
+    {
+	.protocol = "application/pkcs7-encrypted",
+	.get_context = create_pkcs7_context,
+    },
 };
 
 /* for the specified protocol return the context pointer (initializing
@@ -124,5 +167,10 @@ notmuch_crypto_cleanup (notmuch_crypto_t *crypto)
 	crypto->gpgctx = NULL;
     }
 
+    if (crypto->pkcs7ctx) {
+	g_object_unref (crypto->pkcs7ctx);
+	crypto->pkcs7ctx = NULL;
+    }
+
     return 0;
 }
diff --git a/notmuch-client.h b/notmuch-client.h
index 5e0d47508c6a..5f2a11ed8dc5 100644
--- a/notmuch-client.h
+++ b/notmuch-client.h
@@ -37,6 +37,8 @@
 #ifdef GMIME_MAJOR_VERSION
 #define GMIME_ATLEAST_26
 typedef GMimeCryptoContext notmuch_crypto_context_t;
+/* This is automatically included only since gmime 2.6.10 */
+#include <gmime/gmime-pkcs7-context.h>
 #else
 typedef GMimeCipherContext notmuch_crypto_context_t;
 #endif
@@ -78,6 +80,7 @@ typedef struct notmuch_show_format {
 
 typedef struct notmuch_crypto {
     notmuch_crypto_context_t* gpgctx;
+    notmuch_crypto_context_t* pkcs7ctx;
     notmuch_bool_t verify;
     notmuch_bool_t decrypt;
 } notmuch_crypto_t;
@@ -414,8 +417,8 @@ struct mime_node {
 /* Construct a new MIME node pointing to the root message part of
  * message. If crypto->verify is true, signed child parts will be
  * verified. If crypto->decrypt is true, encrypted child parts will be
- * decrypted.  If crypto->gpgctx is NULL, it will be lazily
- * initialized.
+ * decrypted.  If the crypto contexts (crypto->gpgctx or
+ * crypto->pkcs7) are NULL, they will be lazily initialized.
  *
  * Return value:
  *
-- 
2.1.4