reader-pcsc: Handle yubikey reinsertion

Jakuje · frankmorgner · commit fb15a7dd8654 · 2019-11-01T15:50:34.000+01:00
When the application (NSS) does not use WaitForSlotEvent and just opportunistically tries to detect card and reader removals with C_GetSlotInfo() and C_GetSessionInfo(), we might get errors in various plcaes, in the sc_lock() function, when we try to transfer other messages or when we ask for the reader status. This is generally too late to call any disconnect functions because no PC/SC handles are valid anymore. The reader state from PCSC is searched by name so we can be pretty sure it is very similar reader (with same name as the old one) and I hope we can reuse the reader structure and just call the pcsc_connect() on that as we do with invalid handles. Otherwise we detect this issue in the refresh_attributes() (called from C_GetSlotInfo()), where we can report the slot change in the expected manner. Fixes #1822
diff --git a/src/libopensc/reader-pcsc.c b/src/libopensc/reader-pcsc.c
@@ -247,6 +247,7 @@ static int pcsc_internal_transmit(sc_reader_t *reader,
 		case SCARD_W_REMOVED_CARD:
 			return SC_ERROR_CARD_REMOVED;
 		case SCARD_E_INVALID_HANDLE:
+		case SCARD_E_INVALID_VALUE:
 		case SCARD_E_READER_UNAVAILABLE:
 			pcsc_connect(reader);
 			/* return failure so that upper layers will be notified */
@@ -415,7 +416,7 @@ static int refresh_attributes(sc_reader_t *reader)
 				unsigned char atr[SC_MAX_ATR_SIZE];
 				rv = priv->gpriv->SCardStatus(priv->pcsc_card, NULL,
 						&readers_len, &cstate, &prot, atr, &atr_len);
-				if (rv == (LONG)SCARD_W_REMOVED_CARD)
+				if (rv == (LONG)SCARD_W_REMOVED_CARD || rv == (LONG)SCARD_E_INVALID_VALUE)
 					reader->flags |= SC_READER_CARD_CHANGED;
 			}
 		} else {
@@ -660,6 +661,8 @@ static int pcsc_lock(sc_reader_t *reader)
 		PCSC_TRACE(reader, "SCardBeginTransaction returned", rv);
 
 	switch (rv) {
+		case SCARD_E_INVALID_VALUE:
+			/* This is retuned in case of the same reader was re-attached */
 		case SCARD_E_INVALID_HANDLE:
 		case SCARD_E_READER_UNAVAILABLE:
 			r = pcsc_connect(reader);
