NFC: netlink: SE API implementation

Implementation of the NFC_CMD_SE_IO command for sending ISO7816 APDUs to
NFC embedded secure elements. The reply is forwarded to user space
through NFC_CMD_SE_IO as well.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 91 insertions, 0 deletions

diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index 68063b2025da..a3dee05cb64b 100644
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -58,6 +58,7 @@ static const struct nla_policy nfc_genl_policy[NFC_ATTR_MAX + 1] = {
         [NFC_ATTR_LLC_SDP] = { .type = NLA_NESTED },
         [NFC_ATTR_FIRMWARE_NAME] = { .type = NLA_STRING,
                                      .len = NFC_FIRMWARE_NAME_MAXSIZE },
+        [NFC_ATTR_SE_APDU] = { .type = NLA_BINARY },
 };
 
 static const struct nla_policy nfc_sdp_genl_policy[NFC_SDP_ATTR_MAX + 1] = {
@@ -1278,6 +1279,91 @@ static int nfc_genl_dump_ses_done(struct netlink_callback *cb)
         return 0;
 }
 
+struct se_io_ctx {
+        u32 dev_idx;
+        u32 se_idx;
+};
+
+void se_io_cb(void *context, u8 *apdu, size_t apdu_len, int err)
+{
+        struct se_io_ctx *ctx = context;
+        struct sk_buff *msg;
+        void *hdr;
+
+        msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+        if (!msg) {
+                kfree(ctx);
+                return;
+        }
+
+        hdr = genlmsg_put(msg, 0, 0, &nfc_genl_family, 0,
+                          NFC_CMD_SE_IO);
+        if (!hdr)
+                goto free_msg;
+
+        if (nla_put_u32(msg, NFC_ATTR_DEVICE_INDEX, ctx->dev_idx) ||
+            nla_put_u32(msg, NFC_ATTR_SE_INDEX, ctx->se_idx) ||
+            nla_put(msg, NFC_ATTR_SE_APDU, apdu_len, apdu))
+                goto nla_put_failure;
+
+        genlmsg_end(msg, hdr);
+
+        genlmsg_multicast(msg, 0, nfc_genl_event_mcgrp.id, GFP_KERNEL);
+
+        kfree(ctx);
+
+        return;
+
+nla_put_failure:
+        genlmsg_cancel(msg, hdr);
+free_msg:
+        nlmsg_free(msg);
+        kfree(ctx);
+
+        return;
+}
+
+static int nfc_genl_se_io(struct sk_buff *skb, struct genl_info *info)
+{
+        struct nfc_dev *dev;
+        struct se_io_ctx *ctx;
+        u32 dev_idx, se_idx;
+        u8 *apdu;
+        size_t apdu_len;
+
+        if (!info->attrs[NFC_ATTR_DEVICE_INDEX] ||
+            !info->attrs[NFC_ATTR_SE_INDEX] ||
+            !info->attrs[NFC_ATTR_SE_APDU])
+                return -EINVAL;
+
+        dev_idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+        se_idx = nla_get_u32(info->attrs[NFC_ATTR_SE_INDEX]);
+
+        dev = nfc_get_device(dev_idx);
+        if (!dev)
+                return -ENODEV;
+
+        if (!dev->ops || !dev->ops->se_io)
+                return -ENOTSUPP;
+
+        apdu_len = nla_len(info->attrs[NFC_ATTR_SE_APDU]);
+        if (apdu_len == 0)
+                return -EINVAL;
+
+        apdu = nla_data(info->attrs[NFC_ATTR_SE_APDU]);
+        if (!apdu)
+                return -EINVAL;
+
+        ctx = kzalloc(sizeof(struct se_io_ctx), GFP_KERNEL);
+        if (!ctx)
+                return -ENOMEM;
+
+        ctx->dev_idx = dev_idx;
+        ctx->se_idx = se_idx;
+
+        return dev->ops->se_io(dev, se_idx, apdu, apdu_len, se_io_cb, ctx);
+}
+
 static struct genl_ops nfc_genl_ops[] = {
         {
                 .cmd = NFC_CMD_GET_DEVICE,
@@ -1358,6 +1444,11 @@ static struct genl_ops nfc_genl_ops[] = {
                 .done = nfc_genl_dump_ses_done,
                 .policy = nfc_genl_policy,
         },
+        {
+                .cmd = NFC_CMD_SE_IO,
+                .doit = nfc_genl_se_io,
+                .policy = nfc_genl_policy,
+        },
 };