From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:32805) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UHZqk-000438-Co for qemu-devel@nongnu.org; Mon, 18 Mar 2013 09:11:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1UHZqe-0000o6-Jh for qemu-devel@nongnu.org; Mon, 18 Mar 2013 09:11:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:41229) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UHZqe-0000ns-8C for qemu-devel@nongnu.org; Mon, 18 Mar 2013 09:11:32 -0400 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r2IDBVN4026492 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 18 Mar 2013 09:11:31 -0400 From: Alon Levy Date: Mon, 18 Mar 2013 15:10:58 +0200 Message-Id: <1363612272-13713-13-git-send-email-alevy@redhat.com> In-Reply-To: <1363612272-13713-1-git-send-email-alevy@redhat.com> References: <1363612272-13713-1-git-send-email-alevy@redhat.com> Subject: [Qemu-devel] [PATCH 12/26] hw/ccid-card-passthru.c: add atr check List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: mlureau@redhat.com From: Alon Levy Signed-off-by: Alon Levy --- hw/ccid-card-passthru.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) diff --git a/hw/ccid-card-passthru.c b/hw/ccid-card-passthru.c index 3566e55..111894f 100644 --- a/hw/ccid-card-passthru.c +++ b/hw/ccid-card-passthru.c @@ -138,6 +138,59 @@ static void ccid_card_vscard_handle_init( ccid_card_vscard_send_init(card); } +static int check_atr(PassthruState *card, uint8_t *data, int len) +{ + int historical_length, opt_bytes; + int td_count = 0; + int td; + + if (len < 2) { + return 0; + } + historical_length = data[1] & 0xf; + opt_bytes = 0; + if (data[0] != 0x3b && data[0] != 0x3f) { + DPRINTF(card, D_WARN, "atr's T0 is 0x%X, not in {0x3b, 0x3f}\n", + data[0]); + return 0; + } + td_count = 0; + td = data[1] >> 4; + while (td && td_count < 2 && opt_bytes + historical_length + 2 < len) { + td_count++; + if (td & 0x1) { + opt_bytes++; + } + if (td & 0x2) { + opt_bytes++; + } + if (td & 0x4) { + opt_bytes++; + } + if (td & 0x8) { + opt_bytes++; + td = data[opt_bytes + 2] >> 4; + } + } + if (len < 2 + historical_length + opt_bytes) { + DPRINTF(card, D_WARN, + "atr too short: len %d, but historical_len %d, T1 0x%X\n", + len, historical_length, data[1]); + return 0; + } + if (len > 2 + historical_length + opt_bytes) { + DPRINTF(card, D_WARN, + "atr too long: len %d, but hist/opt %d/%d, T1 0x%X\n", + len, historical_length, opt_bytes, data[1]); + /* let it through */ + } + DPRINTF(card, D_VERBOSE, + "atr passes check: %d total length, %d historical, %d optional\n", + len, historical_length, opt_bytes); + + return 1; +} + static void ccid_card_vscard_handle_message(PassthruState *card, VSCMsgHeader *scr_msg_header) { @@ -152,6 +205,12 @@ static void ccid_card_vscard_handle_message(PassthruState *card, VSC_GENERAL_ERROR); break; } + if (!check_atr(card, data, scr_msg_header->length)) { + error_report("ATR is inconsistent, ignoring"); + ccid_card_vscard_send_error(card, scr_msg_header->reader_id, + VSC_GENERAL_ERROR); + break; + } memcpy(card->atr, data, scr_msg_header->length); card->atr_length = scr_msg_header->length; ccid_card_card_inserted(&card->base); -- 1.8.1.4