1 /*
2  * NC-SI (Network Controller Sideband Interface) "echo" model
3  *
4  * Copyright (C) 2016-2018 IBM Corp.
5  *
6  * This code is licensed under the GPL version 2 or later. See the
7  * COPYING file in the top-level directory.
8  */
9 #include "qemu/osdep.h"
10 #include "slirp.h"
11 
12 #include "ncsi-pkt.h"
13 
ncsi_calculate_checksum(uint16_t * data,int len)14 static uint32_t ncsi_calculate_checksum(uint16_t *data, int len)
15 {
16     uint32_t checksum = 0;
17     int i;
18 
19     /*
20      * 32-bit unsigned sum of the NC-SI packet header and NC-SI packet
21      * payload interpreted as a series of 16-bit unsigned integer values.
22      */
23     for (i = 0; i < len; i++) {
24         checksum += htons(data[i]);
25     }
26 
27     checksum = (~checksum + 1);
28     return checksum;
29 }
30 
31 /* Get Capabilities */
ncsi_rsp_handler_gc(struct ncsi_rsp_pkt_hdr * rnh)32 static int ncsi_rsp_handler_gc(struct ncsi_rsp_pkt_hdr *rnh)
33 {
34     struct ncsi_rsp_gc_pkt *rsp = (struct ncsi_rsp_gc_pkt *) rnh;
35 
36     rsp->cap = htonl(~0);
37     rsp->bc_cap = htonl(~0);
38     rsp->mc_cap = htonl(~0);
39     rsp->buf_cap = htonl(~0);
40     rsp->aen_cap = htonl(~0);
41     rsp->vlan_mode = 0xff;
42     rsp->uc_cnt = 2;
43     return 0;
44 }
45 
46 /* Get Link status */
ncsi_rsp_handler_gls(struct ncsi_rsp_pkt_hdr * rnh)47 static int ncsi_rsp_handler_gls(struct ncsi_rsp_pkt_hdr *rnh)
48 {
49     struct ncsi_rsp_gls_pkt *rsp = (struct ncsi_rsp_gls_pkt *) rnh;
50 
51     rsp->status = htonl(0x1);
52     return 0;
53 }
54 
55 /* Get Parameters */
ncsi_rsp_handler_gp(struct ncsi_rsp_pkt_hdr * rnh)56 static int ncsi_rsp_handler_gp(struct ncsi_rsp_pkt_hdr *rnh)
57 {
58     struct ncsi_rsp_gp_pkt *rsp = (struct ncsi_rsp_gp_pkt *) rnh;
59 
60     /* no MAC address filters or VLAN filters on the channel */
61     rsp->mac_cnt = 0;
62     rsp->mac_enable = 0;
63     rsp->vlan_cnt = 0;
64     rsp->vlan_enable = 0;
65 
66     return 0;
67 }
68 
69 static const struct ncsi_rsp_handler {
70         unsigned char   type;
71         int             payload;
72         int             (*handler)(struct ncsi_rsp_pkt_hdr *rnh);
73 } ncsi_rsp_handlers[] = {
74         { NCSI_PKT_RSP_CIS,     4, NULL },
75         { NCSI_PKT_RSP_SP,      4, NULL },
76         { NCSI_PKT_RSP_DP,      4, NULL },
77         { NCSI_PKT_RSP_EC,      4, NULL },
78         { NCSI_PKT_RSP_DC,      4, NULL },
79         { NCSI_PKT_RSP_RC,      4, NULL },
80         { NCSI_PKT_RSP_ECNT,    4, NULL },
81         { NCSI_PKT_RSP_DCNT,    4, NULL },
82         { NCSI_PKT_RSP_AE,      4, NULL },
83         { NCSI_PKT_RSP_SL,      4, NULL },
84         { NCSI_PKT_RSP_GLS,    16, ncsi_rsp_handler_gls },
85         { NCSI_PKT_RSP_SVF,     4, NULL },
86         { NCSI_PKT_RSP_EV,      4, NULL },
87         { NCSI_PKT_RSP_DV,      4, NULL },
88         { NCSI_PKT_RSP_SMA,     4, NULL },
89         { NCSI_PKT_RSP_EBF,     4, NULL },
90         { NCSI_PKT_RSP_DBF,     4, NULL },
91         { NCSI_PKT_RSP_EGMF,    4, NULL },
92         { NCSI_PKT_RSP_DGMF,    4, NULL },
93         { NCSI_PKT_RSP_SNFC,    4, NULL },
94         { NCSI_PKT_RSP_GVI,    40, NULL },
95         { NCSI_PKT_RSP_GC,     32, ncsi_rsp_handler_gc },
96         { NCSI_PKT_RSP_GP,     40, ncsi_rsp_handler_gp },
97         { NCSI_PKT_RSP_GCPS,  172, NULL },
98         { NCSI_PKT_RSP_GNS,   172, NULL },
99         { NCSI_PKT_RSP_GNPTS, 172, NULL },
100         { NCSI_PKT_RSP_GPS,     8, NULL },
101         { NCSI_PKT_RSP_OEM,     0, NULL },
102         { NCSI_PKT_RSP_PLDM,    0, NULL },
103         { NCSI_PKT_RSP_GPUUID, 20, NULL }
104 };
105 
106 /*
107  * packet format : ncsi header + payload + checksum
108  */
109 #define NCSI_MAX_PAYLOAD 172
110 #define NCSI_MAX_LEN     (sizeof(struct ncsi_pkt_hdr) + NCSI_MAX_PAYLOAD + 4)
111 
ncsi_input(Slirp * slirp,const uint8_t * pkt,int pkt_len)112 void ncsi_input(Slirp *slirp, const uint8_t *pkt, int pkt_len)
113 {
114     struct ncsi_pkt_hdr *nh = (struct ncsi_pkt_hdr *)(pkt + ETH_HLEN);
115     uint8_t ncsi_reply[ETH_HLEN + NCSI_MAX_LEN];
116     struct ethhdr *reh = (struct ethhdr *)ncsi_reply;
117     struct ncsi_rsp_pkt_hdr *rnh = (struct ncsi_rsp_pkt_hdr *)
118         (ncsi_reply + ETH_HLEN);
119     const struct ncsi_rsp_handler *handler = NULL;
120     int i;
121     int ncsi_rsp_len = sizeof(*nh);
122     uint32_t checksum;
123     uint32_t *pchecksum;
124 
125     memset(ncsi_reply, 0, sizeof(ncsi_reply));
126 
127     memset(reh->h_dest, 0xff, ETH_ALEN);
128     memset(reh->h_source, 0xff, ETH_ALEN);
129     reh->h_proto = htons(ETH_P_NCSI);
130 
131     for (i = 0; i < ARRAY_SIZE(ncsi_rsp_handlers); i++) {
132         if (ncsi_rsp_handlers[i].type == nh->type + 0x80) {
133             handler = &ncsi_rsp_handlers[i];
134             break;
135         }
136     }
137 
138     rnh->common.mc_id      = nh->mc_id;
139     rnh->common.revision   = NCSI_PKT_REVISION;
140     rnh->common.id         = nh->id;
141     rnh->common.type       = nh->type + 0x80;
142     rnh->common.channel    = nh->channel;
143 
144     if (handler) {
145         rnh->common.length = htons(handler->payload);
146         rnh->code          = htons(NCSI_PKT_RSP_C_COMPLETED);
147         rnh->reason        = htons(NCSI_PKT_RSP_R_NO_ERROR);
148 
149         if (handler->handler) {
150             /* TODO: handle errors */
151             handler->handler(rnh);
152         }
153         ncsi_rsp_len += handler->payload;
154     } else {
155         rnh->common.length = 0;
156         rnh->code          = htons(NCSI_PKT_RSP_C_UNAVAILABLE);
157         rnh->reason        = htons(NCSI_PKT_RSP_R_UNKNOWN);
158     }
159 
160     /* Add the optional checksum at the end of the frame. */
161     checksum = ncsi_calculate_checksum((uint16_t *) rnh, ncsi_rsp_len);
162     pchecksum = (uint32_t *)((void *) rnh + ncsi_rsp_len);
163     *pchecksum = htonl(checksum);
164     ncsi_rsp_len += 4;
165 
166     slirp_output(slirp->opaque, ncsi_reply, ETH_HLEN + ncsi_rsp_len);
167 }
168