#include "crypto.h"
#include <strings.h>
+#include "error_util.h"
#define unused(x) x __attribute__ ((unused))
#define ARRAY_SIZE(arr) (sizeof (arr) / sizeof (arr[0]))
-#if (GMIME_MAJOR_VERSION < 3)
-/* Create or pass on a GPG context (GMime 2.6) */
-static notmuch_status_t
-get_gpg_context (_notmuch_crypto_t *crypto, GMimeCryptoContext **ctx)
+void
+_notmuch_crypto_cleanup (unused(_notmuch_crypto_t *crypto))
{
- if (ctx == NULL || crypto == NULL)
- return NOTMUCH_STATUS_NULL_POINTER;
+}
- if (crypto->gpgctx) {
- *ctx = crypto->gpgctx;
- return NOTMUCH_STATUS_SUCCESS;
+GMimeObject *
+_notmuch_crypto_decrypt (bool *attempted,
+ notmuch_decryption_policy_t decrypt,
+ notmuch_message_t *message,
+ GMimeObject *part,
+ GMimeDecryptResult **decrypt_result,
+ GError **err)
+{
+ GMimeObject *ret = NULL;
+
+ if (decrypt == NOTMUCH_DECRYPT_FALSE)
+ return NULL;
+
+ /* try decryption with session key if one is stashed */
+ if (message) {
+ notmuch_message_properties_t *list = NULL;
+
+ for (list = notmuch_message_get_properties (message, "session-key", TRUE);
+ notmuch_message_properties_valid (list); notmuch_message_properties_move_to_next (
+ list)) {
+ if (err && *err) {
+ g_error_free (*err);
+ *err = NULL;
+ }
+ if (attempted)
+ *attempted = true;
+ if (GMIME_IS_MULTIPART_ENCRYPTED (part)) {
+ ret = g_mime_multipart_encrypted_decrypt (GMIME_MULTIPART_ENCRYPTED (part),
+ GMIME_DECRYPT_NONE,
+ notmuch_message_properties_value (list),
+ decrypt_result, err);
+ } else if (GMIME_IS_APPLICATION_PKCS7_MIME (part)) {
+ GMimeApplicationPkcs7Mime *pkcs7 = GMIME_APPLICATION_PKCS7_MIME (part);
+ GMimeSecureMimeType type = g_mime_application_pkcs7_mime_get_smime_type (pkcs7);
+ if (type == GMIME_SECURE_MIME_TYPE_ENVELOPED_DATA) {
+ ret = g_mime_application_pkcs7_mime_decrypt (pkcs7,
+ GMIME_DECRYPT_NONE,
+ notmuch_message_properties_value (
+ list),
+ decrypt_result, err);
+ }
+ }
+ if (ret)
+ break;
+ }
+ if (list)
+ notmuch_message_properties_destroy (list);
+ if (ret)
+ return ret;
+ }
+
+ if (err && *err) {
+ g_error_free (*err);
+ *err = NULL;
}
- /* TODO: GMimePasswordRequestFunc */
- crypto->gpgctx = g_mime_gpg_context_new (NULL, crypto->gpgpath ? crypto->gpgpath : "gpg");
- if (! crypto->gpgctx) {
- return NOTMUCH_STATUS_FAILED_CRYPTO_CONTEXT_CREATION;
+ if (decrypt == NOTMUCH_DECRYPT_AUTO)
+ return ret;
+
+ if (attempted)
+ *attempted = true;
+ GMimeDecryptFlags flags = GMIME_DECRYPT_NONE;
+
+ if (decrypt == NOTMUCH_DECRYPT_TRUE && decrypt_result)
+ flags |= GMIME_DECRYPT_EXPORT_SESSION_KEY;
+ if (GMIME_IS_MULTIPART_ENCRYPTED (part)) {
+ ret = g_mime_multipart_encrypted_decrypt (GMIME_MULTIPART_ENCRYPTED (part), flags, NULL,
+ decrypt_result, err);
+ } else if (GMIME_IS_APPLICATION_PKCS7_MIME (part)) {
+ GMimeApplicationPkcs7Mime *pkcs7 = GMIME_APPLICATION_PKCS7_MIME (part);
+ GMimeSecureMimeType p7type = g_mime_application_pkcs7_mime_get_smime_type (pkcs7);
+ if (p7type == GMIME_SECURE_MIME_TYPE_ENVELOPED_DATA) {
+ ret = g_mime_application_pkcs7_mime_decrypt (pkcs7, flags, NULL,
+ decrypt_result, err);
+ }
}
+ return ret;
+}
- g_mime_gpg_context_set_use_agent ((GMimeGpgContext *) crypto->gpgctx, true);
- g_mime_gpg_context_set_always_trust ((GMimeGpgContext *) crypto->gpgctx, false);
+static int
+_notmuch_message_crypto_destructor (_notmuch_message_crypto_t *msg_crypto)
+{
+ if (! msg_crypto)
+ return 0;
+ if (msg_crypto->sig_list)
+ g_object_unref (msg_crypto->sig_list);
+ if (msg_crypto->payload_subject)
+ talloc_free (msg_crypto->payload_subject);
+ return 0;
+}
- *ctx = crypto->gpgctx;
- return NOTMUCH_STATUS_SUCCESS;
+_notmuch_message_crypto_t *
+_notmuch_message_crypto_new (void *ctx)
+{
+ _notmuch_message_crypto_t *ret = talloc_zero (ctx, _notmuch_message_crypto_t);
+
+ talloc_set_destructor (ret, _notmuch_message_crypto_destructor);
+ return ret;
}
-/* Create or pass on a PKCS7 context (GMime 2.6) */
-static notmuch_status_t
-get_pkcs7_context (_notmuch_crypto_t *crypto, GMimeCryptoContext **ctx)
+notmuch_status_t
+_notmuch_message_crypto_potential_sig_list (_notmuch_message_crypto_t *msg_crypto,
+ GMimeSignatureList *sigs)
{
- if (ctx == NULL || crypto == NULL)
+ if (! msg_crypto)
return NOTMUCH_STATUS_NULL_POINTER;
- if (crypto->pkcs7ctx) {
- *ctx = crypto->pkcs7ctx;
+ /* Signatures that arrive after a payload part during DFS are not
+ * part of the cryptographic envelope: */
+ if (msg_crypto->payload_encountered)
return NOTMUCH_STATUS_SUCCESS;
- }
- /* TODO: GMimePasswordRequestFunc */
- crypto->pkcs7ctx = g_mime_pkcs7_context_new (NULL);
- if (! crypto->pkcs7ctx) {
- return NOTMUCH_STATUS_FAILED_CRYPTO_CONTEXT_CREATION;
- }
+ if (msg_crypto->sig_list)
+ g_object_unref (msg_crypto->sig_list);
+
+ /* This signature list needs to persist as long as the _n_m_crypto
+ * object survives. Increasing its reference counter prevents
+ * garbage-collection until after _n_m_crypto_destroy is
+ * called. */
+ msg_crypto->sig_list = sigs;
+ if (sigs)
+ g_object_ref (sigs);
- g_mime_pkcs7_context_set_always_trust ((GMimePkcs7Context *) crypto->pkcs7ctx,
- false);
+ if (msg_crypto->decryption_status == NOTMUCH_MESSAGE_DECRYPTED_FULL)
+ msg_crypto->signature_encrypted = true;
- *ctx = crypto->pkcs7ctx;
return NOTMUCH_STATUS_SUCCESS;
}
-static const struct {
- const char *protocol;
- notmuch_status_t (*get_context) (_notmuch_crypto_t *crypto, GMimeCryptoContext **ctx);
-} protocols[] = {
- {
- .protocol = "application/pgp-signature",
- .get_context = get_gpg_context,
- },
- {
- .protocol = "application/pgp-encrypted",
- .get_context = get_gpg_context,
- },
- {
- .protocol = "application/pkcs7-signature",
- .get_context = get_pkcs7_context,
- },
- {
- .protocol = "application/x-pkcs7-signature",
- .get_context = get_pkcs7_context,
- },
-};
-
-/* for the specified protocol return the context pointer (initializing
- * if needed) */
-notmuch_status_t
-_notmuch_crypto_get_gmime_ctx_for_protocol (_notmuch_crypto_t *crypto,
- const char *protocol,
- GMimeCryptoContext **ctx)
-{
- if (! protocol)
- return NOTMUCH_STATUS_MALFORMED_CRYPTO_PROTOCOL;
-
- /* As per RFC 1847 section 2.1: "the [protocol] value token is
- * comprised of the type and sub-type tokens of the Content-Type".
- * As per RFC 1521 section 2: "Content-Type values, subtypes, and
- * parameter names as defined in this document are
- * case-insensitive." Thus, we use strcasecmp for the protocol.
- */
- for (size_t i = 0; i < ARRAY_SIZE (protocols); i++) {
- if (strcasecmp (protocol, protocols[i].protocol) == 0)
- return protocols[i].get_context (crypto, ctx);
- }
- return NOTMUCH_STATUS_UNKNOWN_CRYPTO_PROTOCOL;
-}
-void
-_notmuch_crypto_cleanup (_notmuch_crypto_t *crypto)
+bool
+_notmuch_message_crypto_potential_payload (_notmuch_message_crypto_t *msg_crypto, GMimeObject *part,
+ GMimeObject *parent, int childnum)
{
- if (crypto->gpgctx) {
- g_object_unref (crypto->gpgctx);
- crypto->gpgctx = NULL;
+ const char *protected_headers = NULL;
+ const char *forwarded = NULL;
+ const char *subject = NULL;
+
+ if ((! msg_crypto) || (! part))
+ INTERNAL_ERROR ("_notmuch_message_crypto_potential_payload() got NULL for %s\n",
+ msg_crypto? "part" : "msg_crypto");
+
+ /* only fire on the first payload part encountered */
+ if (msg_crypto->payload_encountered)
+ return false;
+
+ /* the first child of multipart/encrypted that matches the
+ * encryption protocol should be "control information" metadata,
+ * not payload. So we skip it. (see
+ * https://tools.ietf.org/html/rfc1847#page-8) */
+ if (parent && GMIME_IS_MULTIPART_ENCRYPTED (parent) && childnum ==
+ GMIME_MULTIPART_ENCRYPTED_VERSION) {
+ const char *enc_type = g_mime_object_get_content_type_parameter (parent, "protocol");
+ GMimeContentType *ct = g_mime_object_get_content_type (part);
+ if (ct && enc_type) {
+ const char *part_type = g_mime_content_type_get_mime_type (ct);
+ if (part_type && strcmp (part_type, enc_type) == 0)
+ return false;
+ }
}
- if (crypto->pkcs7ctx) {
- g_object_unref (crypto->pkcs7ctx);
- crypto->pkcs7ctx = NULL;
+ msg_crypto->payload_encountered = true;
+
+ /* don't bother recording anything if there is no cryptographic
+ * envelope: */
+ if ((msg_crypto->decryption_status != NOTMUCH_MESSAGE_DECRYPTED_FULL) &&
+ (msg_crypto->sig_list == NULL))
+ return false;
+
+ /* Verify that this payload has headers that are intended to be
+ * exported to the larger message: */
+
+ /* Consider a payload that uses Alexei Melinkov's forwarded="no" for
+ * message/global or message/rfc822:
+ * https://tools.ietf.org/html/draft-melnikov-smime-header-signing-05#section-4 */
+ forwarded = g_mime_object_get_content_type_parameter (part, "forwarded");
+ if (GMIME_IS_MESSAGE_PART (part) && forwarded && strcmp (forwarded, "no") == 0) {
+ GMimeMessage *message = g_mime_message_part_get_message (GMIME_MESSAGE_PART (part));
+ subject = g_mime_message_get_subject (message);
+ /* FIXME: handle more than just Subject: at some point */
+ } else {
+ /* Consider "memoryhole"-style protected headers as practiced by Enigmail and K-9 */
+ protected_headers = g_mime_object_get_content_type_parameter (part, "protected-headers");
+ if (protected_headers && strcasecmp ("v1", protected_headers) == 0)
+ subject = g_mime_object_get_header (part, "Subject");
+ /* FIXME: handle more than just Subject: at some point */
}
+
+ if (subject) {
+ if (msg_crypto->payload_subject)
+ talloc_free (msg_crypto->payload_subject);
+ msg_crypto->payload_subject = talloc_strdup (msg_crypto, subject);
+ }
+
+ return true;
}
-#else
-void _notmuch_crypto_cleanup (unused(_notmuch_crypto_t *crypto))
-{
-}
-#endif
-GMimeObject *
-_notmuch_crypto_decrypt (g_mime_3_unused(GMimeCryptoContext* crypto_ctx),
- GMimeMultipartEncrypted *part,
- GMimeDecryptResult **decrypt_result,
- GError **err)
+
+notmuch_status_t
+_notmuch_message_crypto_successful_decryption (_notmuch_message_crypto_t *msg_crypto)
{
- GMimeObject *ret = NULL;
+ if (! msg_crypto)
+ return NOTMUCH_STATUS_NULL_POINTER;
-#if (GMIME_MAJOR_VERSION < 3)
- ret = g_mime_multipart_encrypted_decrypt(part, crypto_ctx,
- decrypt_result, err);
-#else
- ret = g_mime_multipart_encrypted_decrypt(part, GMIME_DECRYPT_NONE, NULL,
- decrypt_result, err);
-#endif
- return ret;
+ /* see the rationale for different values of
+ * _notmuch_message_decryption_status_t in util/crypto.h */
+ if (! msg_crypto->payload_encountered)
+ msg_crypto->decryption_status = NOTMUCH_MESSAGE_DECRYPTED_FULL;
+ else if (msg_crypto->decryption_status == NOTMUCH_MESSAGE_DECRYPTED_NONE)
+ msg_crypto->decryption_status = NOTMUCH_MESSAGE_DECRYPTED_PARTIAL;
+
+ return NOTMUCH_STATUS_SUCCESS;
}