net/decnet/sysctl_net_decnet.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * DECnet       An implementation of the DECnet protocol suite for the LINUX
   4  *              operating system.  DECnet is implemented using the  BSD Socket
   5  *              interface as the means of communication with the user level.
   6  *
   7  *              DECnet sysctl support functions
   8  *
   9  * Author:      Steve Whitehouse <SteveW@ACM.org>
  10  *
  11  *
  12  * Changes:
  13  * Steve Whitehouse - C99 changes and default device handling
  14  * Steve Whitehouse - Memory buffer settings, like the tcp ones
  15  *
  16  */
  17 #include <linux/mm.h>
  18 #include <linux/sysctl.h>
  19 #include <linux/fs.h>
  20 #include <linux/netdevice.h>
  21 #include <linux/string.h>
  22 #include <net/neighbour.h>
  23 #include <net/dst.h>
  24 #include <net/flow.h>
  25
  26 #include <linux/uaccess.h>
  27
  28 #include <net/dn.h>
  29 #include <net/dn_dev.h>
  30 #include <net/dn_route.h>
  31
  32
  33 int decnet_debug_level;
  34 int decnet_time_wait = 30;
  35 int decnet_dn_count = 1;
  36 int decnet_di_count = 3;
  37 int decnet_dr_count = 3;
  38 int decnet_log_martians = 1;
  39 int decnet_no_fc_max_cwnd = NSP_MIN_WINDOW;
  40
  41 /* Reasonable defaults, I hope, based on tcp's defaults */
  42 long sysctl_decnet_mem[3] = { 768 << 3, 1024 << 3, 1536 << 3 };
  43 int sysctl_decnet_wmem[3] = { 4 * 1024, 16 * 1024, 128 * 1024 };
  44 int sysctl_decnet_rmem[3] = { 4 * 1024, 87380, 87380 * 2 };
  45
  46 #ifdef CONFIG_SYSCTL
  47 extern int decnet_dst_gc_interval;
  48 static int min_decnet_time_wait[] = { 5 };
  49 static int max_decnet_time_wait[] = { 600 };
  50 static int min_state_count[] = { 1 };
  51 static int max_state_count[] = { NSP_MAXRXTSHIFT };
  52 static int min_decnet_dst_gc_interval[] = { 1 };
  53 static int max_decnet_dst_gc_interval[] = { 60 };
  54 static int min_decnet_no_fc_max_cwnd[] = { NSP_MIN_WINDOW };
  55 static int max_decnet_no_fc_max_cwnd[] = { NSP_MAX_WINDOW };
  56 static char node_name[7] = "???";
  57
  58 static struct ctl_table_header *dn_table_header = NULL;
  59
  60 /*
  61  * ctype.h :-)
  62  */
  63 #define ISNUM(x) (((x) >= '0') && ((x) <= '9'))
  64 #define ISLOWER(x) (((x) >= 'a') && ((x) <= 'z'))
  65 #define ISUPPER(x) (((x) >= 'A') && ((x) <= 'Z'))
  66 #define ISALPHA(x) (ISLOWER(x) || ISUPPER(x))
  67 #define INVALID_END_CHAR(x) (ISNUM(x) || ISALPHA(x))
  68
  69 static void strip_it(char *str)
  70 {
  71         for(;;) {
  72                 switch (*str) {
  73                 case ' ':
  74                 case '\n':
  75                 case '\r':
  76                 case ':':
  77                         *str = 0;
  78                         /* Fallthrough */
  79                 case 0:
  80                         return;
  81                 }
  82                 str++;
  83         }
  84 }
  85
  86 /*
  87  * Simple routine to parse an ascii DECnet address
  88  * into a network order address.
  89  */
  90 static int parse_addr(__le16 *addr, char *str)
  91 {
  92         __u16 area, node;
  93
  94         while(*str && !ISNUM(*str)) str++;
  95
  96         if (*str == 0)
  97                 return -1;
  98
  99         area = (*str++ - '0');
 100         if (ISNUM(*str)) {
 101                 area *= 10;
 102                 area += (*str++ - '0');
 103         }
 104
 105         if (*str++ != '.')
 106                 return -1;
 107
 108         if (!ISNUM(*str))
 109                 return -1;
 110
 111         node = *str++ - '0';
 112         if (ISNUM(*str)) {
 113                 node *= 10;
 114                 node += (*str++ - '0');
 115         }
 116         if (ISNUM(*str)) {
 117                 node *= 10;
 118                 node += (*str++ - '0');
 119         }
 120         if (ISNUM(*str)) {
 121                 node *= 10;
 122                 node += (*str++ - '0');
 123         }
 124
 125         if ((node > 1023) || (area > 63))
 126                 return -1;
 127
 128         if (INVALID_END_CHAR(*str))
 129                 return -1;
 130
 131         *addr = cpu_to_le16((area << 10) | node);
 132
 133         return 0;
 134 }
 135
 136 static int dn_node_address_handler(struct ctl_table *table, int write,
 137                                 void __user *buffer,
 138                                 size_t *lenp, loff_t *ppos)
 139 {
 140         char addr[DN_ASCBUF_LEN];
 141         size_t len;
 142         __le16 dnaddr;
 143
 144         if (!*lenp || (*ppos && !write)) {
 145                 *lenp = 0;
 146                 return 0;
 147         }
 148
 149         if (write) {
 150                 len = (*lenp < DN_ASCBUF_LEN) ? *lenp : (DN_ASCBUF_LEN-1);
 151
 152                 if (copy_from_user(addr, buffer, len))
 153                         return -EFAULT;
 154
 155                 addr[len] = 0;
 156                 strip_it(addr);
 157
 158                 if (parse_addr(&dnaddr, addr))
 159                         return -EINVAL;
 160
 161                 dn_dev_devices_off();
 162
 163                 decnet_address = dnaddr;
 164
 165                 dn_dev_devices_on();
 166
 167                 *ppos += len;
 168
 169                 return 0;
 170         }
 171
 172         dn_addr2asc(le16_to_cpu(decnet_address), addr);
 173         len = strlen(addr);
 174         addr[len++] = '\n';
 175
 176         if (len > *lenp) len = *lenp;
 177
 178         if (copy_to_user(buffer, addr, len))
 179                 return -EFAULT;
 180
 181         *lenp = len;
 182         *ppos += len;
 183
 184         return 0;
 185 }
 186
 187 static int dn_def_dev_handler(struct ctl_table *table, int write,
 188                                 void __user *buffer,
 189                                 size_t *lenp, loff_t *ppos)
 190 {
 191         size_t len;
 192         struct net_device *dev;
 193         char devname[17];
 194
 195         if (!*lenp || (*ppos && !write)) {
 196                 *lenp = 0;
 197                 return 0;
 198         }
 199
 200         if (write) {
 201                 if (*lenp > 16)
 202                         return -E2BIG;
 203
 204                 if (copy_from_user(devname, buffer, *lenp))
 205                         return -EFAULT;
 206
 207                 devname[*lenp] = 0;
 208                 strip_it(devname);
 209
 210                 dev = dev_get_by_name(&init_net, devname);
 211                 if (dev == NULL)
 212                         return -ENODEV;
 213
 214                 if (dev->dn_ptr == NULL) {
 215                         dev_put(dev);
 216                         return -ENODEV;
 217                 }
 218
 219                 if (dn_dev_set_default(dev, 1)) {
 220                         dev_put(dev);
 221                         return -ENODEV;
 222                 }
 223                 *ppos += *lenp;
 224
 225                 return 0;
 226         }
 227
 228         dev = dn_dev_get_default();
 229         if (dev == NULL) {
 230                 *lenp = 0;
 231                 return 0;
 232         }
 233
 234         strcpy(devname, dev->name);
 235         dev_put(dev);
 236         len = strlen(devname);
 237         devname[len++] = '\n';
 238
 239         if (len > *lenp) len = *lenp;
 240
 241         if (copy_to_user(buffer, devname, len))
 242                 return -EFAULT;
 243
 244         *lenp = len;
 245         *ppos += len;
 246
 247         return 0;
 248 }
 249
 250 static struct ctl_table dn_table[] = {
 251         {
 252                 .procname = "node_address",
 253                 .maxlen = 7,
 254                 .mode = 0644,
 255                 .proc_handler = dn_node_address_handler,
 256         },
 257         {
 258                 .procname = "node_name",
 259                 .data = node_name,
 260                 .maxlen = 7,
 261                 .mode = 0644,
 262                 .proc_handler = proc_dostring,
 263         },
 264         {
 265                 .procname = "default_device",
 266                 .maxlen = 16,
 267                 .mode = 0644,
 268                 .proc_handler = dn_def_dev_handler,
 269         },
 270         {
 271                 .procname = "time_wait",
 272                 .data = &decnet_time_wait,
 273                 .maxlen = sizeof(int),
 274                 .mode = 0644,
 275                 .proc_handler = proc_dointvec_minmax,
 276                 .extra1 = &min_decnet_time_wait,
 277                 .extra2 = &max_decnet_time_wait
 278         },
 279         {
 280                 .procname = "dn_count",
 281                 .data = &decnet_dn_count,
 282                 .maxlen = sizeof(int),
 283                 .mode = 0644,
 284                 .proc_handler = proc_dointvec_minmax,
 285                 .extra1 = &min_state_count,
 286                 .extra2 = &max_state_count
 287         },
 288         {
 289                 .procname = "di_count",
 290                 .data = &decnet_di_count,
 291                 .maxlen = sizeof(int),
 292                 .mode = 0644,
 293                 .proc_handler = proc_dointvec_minmax,
 294                 .extra1 = &min_state_count,
 295                 .extra2 = &max_state_count
 296         },
 297         {
 298                 .procname = "dr_count",
 299                 .data = &decnet_dr_count,
 300                 .maxlen = sizeof(int),
 301                 .mode = 0644,
 302                 .proc_handler = proc_dointvec_minmax,
 303                 .extra1 = &min_state_count,
 304                 .extra2 = &max_state_count
 305         },
 306         {
 307                 .procname = "dst_gc_interval",
 308                 .data = &decnet_dst_gc_interval,
 309                 .maxlen = sizeof(int),
 310                 .mode = 0644,
 311                 .proc_handler = proc_dointvec_minmax,
 312                 .extra1 = &min_decnet_dst_gc_interval,
 313                 .extra2 = &max_decnet_dst_gc_interval
 314         },
 315         {
 316                 .procname = "no_fc_max_cwnd",
 317                 .data = &decnet_no_fc_max_cwnd,
 318                 .maxlen = sizeof(int),
 319                 .mode = 0644,
 320                 .proc_handler = proc_dointvec_minmax,
 321                 .extra1 = &min_decnet_no_fc_max_cwnd,
 322                 .extra2 = &max_decnet_no_fc_max_cwnd
 323         },
 324        {
 325                 .procname = "decnet_mem",
 326                 .data = &sysctl_decnet_mem,
 327                 .maxlen = sizeof(sysctl_decnet_mem),
 328                 .mode = 0644,
 329                 .proc_handler = proc_doulongvec_minmax
 330         },
 331         {
 332                 .procname = "decnet_rmem",
 333                 .data = &sysctl_decnet_rmem,
 334                 .maxlen = sizeof(sysctl_decnet_rmem),
 335                 .mode = 0644,
 336                 .proc_handler = proc_dointvec,
 337         },
 338         {
 339                 .procname = "decnet_wmem",
 340                 .data = &sysctl_decnet_wmem,
 341                 .maxlen = sizeof(sysctl_decnet_wmem),
 342                 .mode = 0644,
 343                 .proc_handler = proc_dointvec,
 344         },
 345         {
 346                 .procname = "debug",
 347                 .data = &decnet_debug_level,
 348                 .maxlen = sizeof(int),
 349                 .mode = 0644,
 350                 .proc_handler = proc_dointvec,
 351         },
 352         { }
 353 };
 354
 355 void dn_register_sysctl(void)
 356 {
 357         dn_table_header = register_net_sysctl(&init_net, "net/decnet", dn_table);
 358 }
 359
 360 void dn_unregister_sysctl(void)
 361 {
 362         unregister_net_sysctl_table(dn_table_header);
 363 }
 364
 365 #else  /* CONFIG_SYSCTL */
 366 void dn_unregister_sysctl(void)
 367 {
 368 }
 369 void dn_register_sysctl(void)
 370 {
 371 }
 372
 373 #endif