cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

cfveil.c (2583B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Copyright (C) ST-Ericsson AB 2010
      4 * Author:	Sjur Brendeland
      5 */
      6
      7#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
      8
      9#include <linux/stddef.h>
     10#include <linux/slab.h>
     11#include <net/caif/caif_layer.h>
     12#include <net/caif/cfsrvl.h>
     13#include <net/caif/cfpkt.h>
     14
     15#define VEI_PAYLOAD  0x00
     16#define VEI_CMD_BIT  0x80
     17#define VEI_FLOW_OFF 0x81
     18#define VEI_FLOW_ON  0x80
     19#define VEI_SET_PIN  0x82
     20
     21#define container_obj(layr) container_of(layr, struct cfsrvl, layer)
     22
     23static int cfvei_receive(struct cflayer *layr, struct cfpkt *pkt);
     24static int cfvei_transmit(struct cflayer *layr, struct cfpkt *pkt);
     25
     26struct cflayer *cfvei_create(u8 channel_id, struct dev_info *dev_info)
     27{
     28	struct cfsrvl *vei = kzalloc(sizeof(struct cfsrvl), GFP_ATOMIC);
     29	if (!vei)
     30		return NULL;
     31	caif_assert(offsetof(struct cfsrvl, layer) == 0);
     32	cfsrvl_init(vei, channel_id, dev_info, true);
     33	vei->layer.receive = cfvei_receive;
     34	vei->layer.transmit = cfvei_transmit;
     35	snprintf(vei->layer.name, CAIF_LAYER_NAME_SZ, "vei%d", channel_id);
     36	return &vei->layer;
     37}
     38
     39static int cfvei_receive(struct cflayer *layr, struct cfpkt *pkt)
     40{
     41	u8 cmd;
     42	int ret;
     43	caif_assert(layr->up != NULL);
     44	caif_assert(layr->receive != NULL);
     45	caif_assert(layr->ctrlcmd != NULL);
     46
     47
     48	if (cfpkt_extr_head(pkt, &cmd, 1) < 0) {
     49		pr_err("Packet is erroneous!\n");
     50		cfpkt_destroy(pkt);
     51		return -EPROTO;
     52	}
     53	switch (cmd) {
     54	case VEI_PAYLOAD:
     55		ret = layr->up->receive(layr->up, pkt);
     56		return ret;
     57	case VEI_FLOW_OFF:
     58		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_OFF_IND, 0);
     59		cfpkt_destroy(pkt);
     60		return 0;
     61	case VEI_FLOW_ON:
     62		layr->ctrlcmd(layr, CAIF_CTRLCMD_FLOW_ON_IND, 0);
     63		cfpkt_destroy(pkt);
     64		return 0;
     65	case VEI_SET_PIN:	/* SET RS232 PIN */
     66		cfpkt_destroy(pkt);
     67		return 0;
     68	default:		/* SET RS232 PIN */
     69		pr_warn("Unknown VEI control packet %d (0x%x)!\n", cmd, cmd);
     70		cfpkt_destroy(pkt);
     71		return -EPROTO;
     72	}
     73}
     74
     75static int cfvei_transmit(struct cflayer *layr, struct cfpkt *pkt)
     76{
     77	u8 tmp = 0;
     78	struct caif_payload_info *info;
     79	int ret;
     80	struct cfsrvl *service = container_obj(layr);
     81	if (!cfsrvl_ready(service, &ret))
     82		goto err;
     83	caif_assert(layr->dn != NULL);
     84	caif_assert(layr->dn->transmit != NULL);
     85
     86	if (cfpkt_add_head(pkt, &tmp, 1) < 0) {
     87		pr_err("Packet is erroneous!\n");
     88		ret = -EPROTO;
     89		goto err;
     90	}
     91
     92	/* Add info-> for MUX-layer to route the packet out. */
     93	info = cfpkt_info(pkt);
     94	info->channel_id = service->layer.id;
     95	info->hdr_len = 1;
     96	info->dev_info = &service->dev_info;
     97	return layr->dn->transmit(layr->dn, pkt);
     98err:
     99	cfpkt_destroy(pkt);
    100	return ret;
    101}