crypto: make shared crypto code behave library-like

If we're going to reuse the crypto code across both the library and
the client, then it needs to report error states properly and not
write to stderr.

diff --git a/lib/database.cc b/lib/database.cc
index 35c66939bdcf9d462f03caede67c158cb9f01d86..02444e09e965c4ce0dbc396d5ed48b5abce5ba0a 100644 (file)
--- a/lib/database.cc
+++ b/lib/database.cc
@@ -413,6 +413,12 @@ notmuch_status_to_string (notmuch_status_t status)
        return "Operation requires a database upgrade";
     case NOTMUCH_STATUS_PATH_ERROR:
        return "Path supplied is illegal for this function";
+    case NOTMUCH_STATUS_MALFORMED_CRYPTO_PROTOCOL:
+       return "Crypto protocol missing, malformed, or unintelligible";
+    case NOTMUCH_STATUS_FAILED_CRYPTO_CONTEXT_CREATION:
+       return "Crypto engine initialization failure";
+    case NOTMUCH_STATUS_UNKNOWN_CRYPTO_PROTOCOL:
+       return "Unknown crypto protocol";
     default:
     case NOTMUCH_STATUS_LAST_STATUS:
        return "Unknown error status value";

diff --git a/lib/notmuch.h b/lib/notmuch.h
index e8e0cc12a62b9970cb19ed160bd5b04b967599ce..669e01b120b3cbbd797389f5f7f2e63e116e5e72 100644 (file)
--- a/lib/notmuch.h
+++ b/lib/notmuch.h
@@ -191,6 +191,23 @@ typedef enum _notmuch_status {
      * function, in a way not covered by a more specific argument.
      */
     NOTMUCH_STATUS_ILLEGAL_ARGUMENT,
+    /**
+     * A MIME object claimed to have cryptographic protection which
+     * notmuch tried to handle, but the protocol was not specified in
+     * an intelligible way.
+     */
+    NOTMUCH_STATUS_MALFORMED_CRYPTO_PROTOCOL,
+    /**
+     * Notmuch attempted to do crypto processing, but could not
+     * initialize the engine needed to do so.
+     */
+    NOTMUCH_STATUS_FAILED_CRYPTO_CONTEXT_CREATION,
+    /**
+     * A MIME object claimed to have cryptographic protection, and
+     * notmuch attempted to process it, but the specific protocol was
+     * something that notmuch doesn't know how to handle.
+     */
+    NOTMUCH_STATUS_UNKNOWN_CRYPTO_PROTOCOL,
     /**
      * Not an actual status value. Just a way to find out how many
      * valid status values there are.

diff --git a/mime-node.c b/mime-node.c
index d48be4c46695c072197505c9ed7413a64c089af0..c3d5cb9b47595ad2a43606e8faf08b8a0e28283d 100644 (file)
--- a/mime-node.c
+++ b/mime-node.c
@@ -269,7 +269,12 @@ _mime_node_create (mime_node_t *parent, GMimeObject *part)
        || (GMIME_IS_MULTIPART_SIGNED (part) && node->ctx->crypto->verify)) {
        GMimeContentType *content_type = g_mime_object_get_content_type (part);
        const char *protocol = g_mime_content_type_get_parameter (content_type, "protocol");
-       cryptoctx = _notmuch_crypto_get_gmime_context (node->ctx->crypto, protocol);
+       notmuch_status_t status;
+       status = _notmuch_crypto_get_gmime_ctx_for_protocol (node->ctx->crypto,
+                                                            protocol, &cryptoctx);
+       if (status) /* this is a warning, not an error */
+           fprintf (stderr, "Warning: %s (%s).\n", notmuch_status_to_string (status),
+                    protocol ? protocol : "NULL");
        if (!cryptoctx)
            return NULL;
     }

diff --git a/util/crypto.c b/util/crypto.c
index c51d67ed0d2c96a669227753d42dfa38adbb353b..5c84282eed62ebfc05c98b2b09ee890d7a78e662 100644 (file)
--- a/util/crypto.c
+++ b/util/crypto.c
@@ -25,85 +25,86 @@
 #define ARRAY_SIZE(arr) (sizeof (arr) / sizeof (arr[0]))
 
 #if (GMIME_MAJOR_VERSION < 3)
-/* Create a GPG context (GMime 2.6) */
-static GMimeCryptoContext *
-create_gpg_context (_notmuch_crypto_t *crypto)
+/* Create or pass on a GPG context (GMime 2.6) */
+static notmuch_status_t
+get_gpg_context (_notmuch_crypto_t *crypto, GMimeCryptoContext **ctx)
 {
-    GMimeCryptoContext *gpgctx;
+    if (ctx == NULL || crypto == NULL)
+       return NOTMUCH_STATUS_NULL_POINTER;
 
-    if (crypto->gpgctx)
-       return crypto->gpgctx;
+    if (crypto->gpgctx) {
+       *ctx = crypto->gpgctx;
+       return NOTMUCH_STATUS_SUCCESS;
+    }
 
     /* TODO: GMimePasswordRequestFunc */
-    gpgctx = g_mime_gpg_context_new (NULL, crypto->gpgpath ? crypto->gpgpath : "gpg");
-    if (! gpgctx) {
-       fprintf (stderr, "Failed to construct gpg context.\n");
-       return NULL;
+    crypto->gpgctx = g_mime_gpg_context_new (NULL, crypto->gpgpath ? crypto->gpgpath : "gpg");
+    if (! crypto->gpgctx) {
+       return NOTMUCH_STATUS_FAILED_CRYPTO_CONTEXT_CREATION;
     }
-    crypto->gpgctx = gpgctx;
 
-    g_mime_gpg_context_set_use_agent ((GMimeGpgContext *) gpgctx, true);
-    g_mime_gpg_context_set_always_trust ((GMimeGpgContext *) gpgctx, false);
+    g_mime_gpg_context_set_use_agent ((GMimeGpgContext *) crypto->gpgctx, true);
+    g_mime_gpg_context_set_always_trust ((GMimeGpgContext *) crypto->gpgctx, false);
 
-    return gpgctx;
+    *ctx = crypto->gpgctx;
+    return NOTMUCH_STATUS_SUCCESS;
 }
 
-/* Create a PKCS7 context (GMime 2.6) */
-static GMimeCryptoContext *
-create_pkcs7_context (_notmuch_crypto_t *crypto)
+/* Create or pass on a PKCS7 context (GMime 2.6) */
+static notmuch_status_t
+get_pkcs7_context (_notmuch_crypto_t *crypto, GMimeCryptoContext **ctx)
 {
-    GMimeCryptoContext *pkcs7ctx;
+    if (ctx == NULL || crypto == NULL)
+       return NOTMUCH_STATUS_NULL_POINTER;
 
-    if (crypto->pkcs7ctx)
-       return crypto->pkcs7ctx;
+    if (crypto->pkcs7ctx) {
+       *ctx = crypto->pkcs7ctx;
+       return NOTMUCH_STATUS_SUCCESS;
+    }
 
     /* TODO: GMimePasswordRequestFunc */
-    pkcs7ctx = g_mime_pkcs7_context_new (NULL);
-    if (! pkcs7ctx) {
-       fprintf (stderr, "Failed to construct pkcs7 context.\n");
-       return NULL;
+    crypto->pkcs7ctx = g_mime_pkcs7_context_new (NULL);
+    if (! crypto->pkcs7ctx) {
+       return NOTMUCH_STATUS_FAILED_CRYPTO_CONTEXT_CREATION;
     }
-    crypto->pkcs7ctx = pkcs7ctx;
 
-    g_mime_pkcs7_context_set_always_trust ((GMimePkcs7Context *) pkcs7ctx,
+    g_mime_pkcs7_context_set_always_trust ((GMimePkcs7Context *) crypto->pkcs7ctx,
                                           false);
 
-    return pkcs7ctx;
+    *ctx = crypto->pkcs7ctx;
+    return NOTMUCH_STATUS_SUCCESS;
 }
 static const struct {
     const char *protocol;
-    GMimeCryptoContext *(*get_context) (_notmuch_crypto_t *crypto);
+    notmuch_status_t (*get_context) (_notmuch_crypto_t *crypto, GMimeCryptoContext **ctx);
 } protocols[] = {
     {
        .protocol = "application/pgp-signature",
-       .get_context = create_gpg_context,
+       .get_context = get_gpg_context,
     },
     {
        .protocol = "application/pgp-encrypted",
-       .get_context = create_gpg_context,
+       .get_context = get_gpg_context,
     },
     {
        .protocol = "application/pkcs7-signature",
-       .get_context = create_pkcs7_context,
+       .get_context = get_pkcs7_context,
     },
     {
        .protocol = "application/x-pkcs7-signature",
-       .get_context = create_pkcs7_context,
+       .get_context = get_pkcs7_context,
     },
 };
 
 /* for the specified protocol return the context pointer (initializing
  * if needed) */
-GMimeCryptoContext *
-_notmuch_crypto_get_gmime_context (_notmuch_crypto_t *crypto, const char *protocol)
+notmuch_status_t
+_notmuch_crypto_get_gmime_ctx_for_protocol (_notmuch_crypto_t *crypto,
+                                           const char *protocol,
+                                           GMimeCryptoContext **ctx)
 {
-    GMimeCryptoContext *cryptoctx = NULL;
-    size_t i;
-
-    if (! protocol) {
-       fprintf (stderr, "Cryptographic protocol is empty.\n");
-       return cryptoctx;
-    }
+    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".
@@ -111,15 +112,12 @@ _notmuch_crypto_get_gmime_context (_notmuch_crypto_t *crypto, const char *protoc
      * parameter names as defined in this document are
      * case-insensitive."  Thus, we use strcasecmp for the protocol.
      */
-    for (i = 0; i < ARRAY_SIZE (protocols); i++) {
+    for (size_t i = 0; i < ARRAY_SIZE (protocols); i++) {
        if (strcasecmp (protocol, protocols[i].protocol) == 0)
-           return protocols[i].get_context (crypto);
+           return protocols[i].get_context (crypto, ctx);
     }
 
-    fprintf (stderr, "Unknown or unsupported cryptographic protocol %s.\n",
-            protocol);
-
-    return NULL;
+    return NOTMUCH_STATUS_UNKNOWN_CRYPTO_PROTOCOL;
 }
 
 void

diff --git a/util/crypto.h b/util/crypto.h
index 80628dc528d258057561a37168d116437fa2d75c..1ff0297db45077bdb491dfbf8d27775ae3c280bd 100644 (file)
--- a/util/crypto.h
+++ b/util/crypto.h
@@ -4,6 +4,7 @@
 #include <stdbool.h>
 #if (GMIME_MAJOR_VERSION < 3)
 #include "gmime-extra.h"
+#include "notmuch.h"
 #endif
 
 typedef struct _notmuch_crypto {
@@ -18,8 +19,10 @@ typedef struct _notmuch_crypto {
 
 
 #if (GMIME_MAJOR_VERSION < 3)
-GMimeCryptoContext *
-_notmuch_crypto_get_gmime_context (_notmuch_crypto_t *crypto, const char *protocol);
+notmuch_status_t
+_notmuch_crypto_get_gmime_ctx_for_protocol (_notmuch_crypto_t *crypto,
+                                           const char *protocol,
+                                           GMimeCryptoContext **ctx);
 #endif
 
 void