[Libguestfs] [nbdkit PATCH] vddk: advise user on obscure thumbprint mismatch error condition
If the thumbprint parameter is wrong, it's only reported in
VixDiskLib_Open(), and then with the non-descript VIX_E_FAIL error code.
If the user typed or cut-and-pasted the thumbprint incorrectly, said
"Unkown error" message is not helpful for fixing the nbkit command line.
Hint at the thumbprint as the potential culprit.
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1905772
Signed-off-by: Laszlo Ersek <lersek(a)redhat.com>
---
plugins/vddk/vddk-structs.h | 1 +
plugins/vddk/vddk.c | 20 ++++++++++++++++++++
2 files changed, 21 insertions(+)
diff --git a/plugins/vddk/vddk-structs.h b/plugins/vddk/vddk-structs.h
index 799c4aecc5b8..4c7c6fe2e4fc 100644
--- a/plugins/vddk/vddk-structs.h
+++ b/plugins/vddk/vddk-structs.h
@@ -43,6 +43,7 @@
typedef uint64_t VixError;
#define VIX_OK 0
+#define VIX_E_FAIL 1
#define VIX_E_NOT_SUPPORTED 6
#define VIX_ASYNC 25000
diff --git a/plugins/vddk/vddk.c b/plugins/vddk/vddk.c
index 2ea071d641e6..dbd3fdbe09af 100644
--- a/plugins/vddk/vddk.c
+++ b/plugins/vddk/vddk.c
@@ -769,6 +769,26 @@ vddk_open (int readonly)
VDDK_CALL_END (VixDiskLib_Open, 0);
if (err != VIX_OK) {
VDDK_ERROR (err, "VixDiskLib_Open: %s", filename);
+
+ /* Attempt to advise the user on the extremely helpful "Unknown error"
+ * result of VixDiskLib_Open(). The one reason we've seen for this error
+ * mode is a thumbprint mismatch (RHBZ#1905772). Note that:
+ *
+ * (1) The thumbprint (as a part of "h->params") is passed to
+ * VixDiskLib_ConnectEx() above, but the fingerprint mismatch is
+ * detected only inside VixDiskLib_Open().
+ *
+ * (2) "thumb_print" may be NULL -- vddk_config_complete() is correct not
to
+ * require a non-NULL "thumb_print" for a remote connection; the
sample
+ * program "vixDiskLibSample.cpp" in vddk-7.0.3 explicitly permits
+ * "-thumb" to be absent.
+ */
+ if (is_remote && err == VIX_E_FAIL)
+ nbdkit_error ("Please verify whether the \"thumbprint\" parameter
(%s) "
+ "matches the SHA1 fingerprint of the remote VMware "
+ "server. Refer to nbdkit-vddk-plugin(1) section "
+ "\"THUMBPRINTS\" for details.",
+ thumb_print == NULL ? "not specified" : thumb_print);
goto err2;
}
base-commit: 5007409b03486fa4b43526412d3db8de50325efd
--
2.19.1.3.g30247aa5d201