src/network/networkd-can.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <net/if.h>
   4 #include <linux/can/netlink.h>
   5
   6 #include "netlink-util.h"
   7 #include "networkd-can.h"
   8 #include "networkd-link.h"
   9 #include "networkd-manager.h"
  10 #include "parse-util.h"
  11 #include "string-util.h"
  12
  13 #define CAN_TERMINATION_OHM_VALUE 120
  14
  15 int config_parse_can_bitrate(
  16                 const char* unit,
  17                 const char *filename,
  18                 unsigned line,
  19                 const char *section,
  20                 unsigned section_line,
  21                 const char *lvalue,
  22                 int ltype,
  23                 const char *rvalue,
  24                 void *data,
  25                 void *userdata) {
  26
  27         uint32_t *br = data;
  28         uint64_t sz;
  29         int r;
  30
  31         assert(filename);
  32         assert(lvalue);
  33         assert(rvalue);
  34         assert(data);
  35
  36         r = parse_size(rvalue, 1000, &sz);
  37         if (r < 0) {
  38                 log_syntax(unit, LOG_WARNING, filename, line, r,
  39                            "Failed to parse can bitrate '%s', ignoring: %m", rvalue);
  40                 return 0;
  41         }
  42
  43         /* Linux uses __u32 for bitrates, so the value should not exceed that. */
  44         if (sz <= 0 || sz > UINT32_MAX) {
  45                 log_syntax(unit, LOG_WARNING, filename, line, 0,
  46                            "Bit rate out of permitted range 1...4294967295");
  47                 return 0;
  48         }
  49
  50         *br = (uint32_t) sz;
  51
  52         return 0;
  53 }
  54
  55 static int link_set_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
  56         int r;
  57
  58         assert(link);
  59
  60         if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
  61                 return 1;
  62
  63         r = sd_netlink_message_get_errno(m);
  64         if (r < 0 && r != -EEXIST) {
  65                 log_link_message_warning_errno(link, m, r, "Failed to configure CAN link");
  66                 link_enter_failed(link);
  67                 return 1;
  68         }
  69
  70         log_link_debug(link, "Link set");
  71
  72         r = link_activate(link);
  73         if (r < 0) {
  74                 link_enter_failed(link);
  75                 return 1;
  76         }
  77
  78         link->can_configured = true;
  79         link_check_ready(link);
  80
  81         return 1;
  82 }
  83
  84 static int link_set_can(Link *link) {
  85         _cleanup_(sd_netlink_message_unrefp) sd_netlink_message *m = NULL;
  86         struct can_ctrlmode cm = {};
  87         int r;
  88
  89         assert(link);
  90         assert(link->network);
  91         assert(link->manager);
  92         assert(link->manager->rtnl);
  93
  94         log_link_debug(link, "Configuring CAN link.");
  95
  96         r = sd_rtnl_message_new_link(link->manager->rtnl, &m, RTM_NEWLINK, link->ifindex);
  97         if (r < 0)
  98                 return log_link_error_errno(link, r, "Failed to allocate netlink message: %m");
  99
 100         r = sd_netlink_message_set_flags(m, NLM_F_REQUEST | NLM_F_ACK);
 101         if (r < 0)
 102                 return log_link_error_errno(link, r, "Could not set netlink flags: %m");
 103
 104         r = sd_netlink_message_open_container(m, IFLA_LINKINFO);
 105         if (r < 0)
 106                 return log_link_error_errno(link, r, "Failed to open netlink container: %m");
 107
 108         r = sd_netlink_message_open_container_union(m, IFLA_INFO_DATA, link->kind);
 109         if (r < 0)
 110                 return log_link_error_errno(link, r, "Could not append IFLA_INFO_DATA attribute: %m");
 111
 112         if (link->network->can_bitrate > 0 || link->network->can_sample_point > 0) {
 113                 struct can_bittiming bt = {
 114                         .bitrate = link->network->can_bitrate,
 115                         .sample_point = link->network->can_sample_point,
 116                 };
 117
 118                 log_link_debug(link, "Setting bitrate = %d bit/s", bt.bitrate);
 119                 if (link->network->can_sample_point > 0)
 120                         log_link_debug(link, "Setting sample point = %d.%d%%", bt.sample_point / 10, bt.sample_point % 10);
 121                 else
 122                         log_link_debug(link, "Using default sample point");
 123
 124                 r = sd_netlink_message_append_data(m, IFLA_CAN_BITTIMING, &bt, sizeof(bt));
 125                 if (r < 0)
 126                         return log_link_error_errno(link, r, "Could not append IFLA_CAN_BITTIMING attribute: %m");
 127         }
 128
 129         if (link->network->can_data_bitrate > 0 || link->network->can_data_sample_point > 0) {
 130                 struct can_bittiming bt = {
 131                         .bitrate = link->network->can_data_bitrate,
 132                         .sample_point = link->network->can_data_sample_point,
 133                 };
 134
 135                 log_link_debug(link, "Setting data bitrate = %d bit/s", bt.bitrate);
 136                 if (link->network->can_data_sample_point > 0)
 137                         log_link_debug(link, "Setting data sample point = %d.%d%%", bt.sample_point / 10, bt.sample_point % 10);
 138                 else
 139                         log_link_debug(link, "Using default data sample point");
 140
 141                 r = sd_netlink_message_append_data(m, IFLA_CAN_DATA_BITTIMING, &bt, sizeof(bt));
 142                 if (r < 0)
 143                         return log_link_error_errno(link, r, "Could not append IFLA_CAN_DATA_BITTIMING attribute: %m");
 144         }
 145
 146         if (link->network->can_fd_mode >= 0) {
 147                 cm.mask |= CAN_CTRLMODE_FD;
 148                 SET_FLAG(cm.flags, CAN_CTRLMODE_FD, link->network->can_fd_mode);
 149                 log_link_debug(link, "Setting FD mode to '%s'.", yes_no(link->network->can_fd_mode));
 150         }
 151
 152         if (link->network->can_non_iso >= 0) {
 153                 cm.mask |= CAN_CTRLMODE_FD_NON_ISO;
 154                 SET_FLAG(cm.flags, CAN_CTRLMODE_FD_NON_ISO, link->network->can_non_iso);
 155                 log_link_debug(link, "Setting FD non-ISO mode to '%s'.", yes_no(link->network->can_non_iso));
 156         }
 157
 158         if (link->network->can_restart_us > 0) {
 159                 char time_string[FORMAT_TIMESPAN_MAX];
 160                 uint64_t restart_ms;
 161
 162                 if (link->network->can_restart_us == USEC_INFINITY)
 163                         restart_ms = 0;
 164                 else
 165                         restart_ms = DIV_ROUND_UP(link->network->can_restart_us, USEC_PER_MSEC);
 166
 167                 format_timespan(time_string, FORMAT_TIMESPAN_MAX, restart_ms * 1000, MSEC_PER_SEC);
 168
 169                 if (restart_ms > UINT32_MAX)
 170                         return log_link_error_errno(link, SYNTHETIC_ERRNO(ERANGE), "restart timeout (%s) too big.", time_string);
 171
 172                 log_link_debug(link, "Setting restart = %s", time_string);
 173
 174                 r = sd_netlink_message_append_u32(m, IFLA_CAN_RESTART_MS, restart_ms);
 175                 if (r < 0)
 176                         return log_link_error_errno(link, r, "Could not append IFLA_CAN_RESTART_MS attribute: %m");
 177         }
 178
 179         if (link->network->can_triple_sampling >= 0) {
 180                 cm.mask |= CAN_CTRLMODE_3_SAMPLES;
 181                 SET_FLAG(cm.flags, CAN_CTRLMODE_3_SAMPLES, link->network->can_triple_sampling);
 182                 log_link_debug(link, "Setting triple-sampling to '%s'.", yes_no(link->network->can_triple_sampling));
 183         }
 184
 185         if (link->network->can_berr_reporting >= 0) {
 186                 cm.mask |= CAN_CTRLMODE_BERR_REPORTING;
 187                 SET_FLAG(cm.flags, CAN_CTRLMODE_BERR_REPORTING, link->network->can_berr_reporting);
 188                 log_link_debug(link, "Setting bus error reporting to '%s'.", yes_no(link->network->can_berr_reporting));
 189         }
 190
 191         if (link->network->can_listen_only >= 0) {
 192                 cm.mask |= CAN_CTRLMODE_LISTENONLY;
 193                 SET_FLAG(cm.flags, CAN_CTRLMODE_LISTENONLY, link->network->can_listen_only);
 194                 log_link_debug(link, "Setting listen-only mode to '%s'.", yes_no(link->network->can_listen_only));
 195         }
 196
 197         if (cm.mask != 0) {
 198                 r = sd_netlink_message_append_data(m, IFLA_CAN_CTRLMODE, &cm, sizeof(cm));
 199                 if (r < 0)
 200                         return log_link_error_errno(link, r, "Could not append IFLA_CAN_CTRLMODE attribute: %m");
 201         }
 202
 203         if (link->network->can_termination >= 0) {
 204
 205                 log_link_debug(link, "Setting can-termination to '%s'.", yes_no(link->network->can_termination));
 206
 207                 r = sd_netlink_message_append_u16(m, IFLA_CAN_TERMINATION,
 208                                 link->network->can_termination ? CAN_TERMINATION_OHM_VALUE : 0);
 209                 if (r < 0)
 210                         return log_link_error_errno(link, r, "Could not append IFLA_CAN_TERMINATION attribute: %m");
 211
 212         }
 213
 214         r = sd_netlink_message_close_container(m);
 215         if (r < 0)
 216                 return log_link_error_errno(link, r, "Failed to close netlink container: %m");
 217
 218         r = sd_netlink_message_close_container(m);
 219         if (r < 0)
 220                 return log_link_error_errno(link, r, "Failed to close netlink container: %m");
 221
 222         r = netlink_call_async(link->manager->rtnl, NULL, m, link_set_handler,
 223                                link_netlink_destroy_callback, link);
 224         if (r < 0)
 225                 return log_link_error_errno(link, r, "Could not send rtnetlink message: %m");
 226
 227         link_ref(link);
 228
 229         return 0;
 230 }
 231
 232 static int link_down_handler(sd_netlink *rtnl, sd_netlink_message *m, Link *link) {
 233         int r;
 234
 235         assert(link);
 236
 237         if (IN_SET(link->state, LINK_STATE_FAILED, LINK_STATE_LINGER))
 238                 return 1;
 239
 240         r = sd_netlink_message_get_errno(m);
 241         if (r < 0) {
 242                 log_link_message_warning_errno(link, m, r, "Could not bring down interface");
 243                 link_enter_failed(link);
 244                 return 1;
 245         }
 246
 247         r = link_set_can(link);
 248         if (r < 0)
 249                 link_enter_failed(link);
 250
 251         return 1;
 252 }
 253
 254 int link_configure_can(Link *link) {
 255         int r;
 256
 257         link_set_state(link, LINK_STATE_CONFIGURING);
 258
 259         if (streq_ptr(link->kind, "can")) {
 260                 /* The CAN interface must be down to configure bitrate, etc... */
 261                 if ((link->flags & IFF_UP))
 262                         r = link_down(link, link_down_handler);
 263                 else
 264                         r = link_set_can(link);
 265                 if (r < 0)
 266                         link_enter_failed(link);
 267                 return r;
 268         }
 269
 270         r = link_activate(link);
 271         if (r < 0)
 272                 return r;
 273
 274         link->can_configured = true;
 275         link_check_ready(link);
 276
 277         return 0;
 278 }