net/decnet/sysctl_net_decnet.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * DECnet       An implementation of the DECnet protocol suite for the LINUX
0004  *              operating system.  DECnet is implemented using the  BSD Socket
0005  *              interface as the means of communication with the user level.
0006  *
0007  *              DECnet sysctl support functions
0008  *
0009  * Author:      Steve Whitehouse <SteveW@ACM.org>
0010  *
0011  *
0012  * Changes:
0013  * Steve Whitehouse - C99 changes and default device handling
0014  * Steve Whitehouse - Memory buffer settings, like the tcp ones
0015  *
0016  */
0017 #include <linux/mm.h>
0018 #include <linux/sysctl.h>
0019 #include <linux/fs.h>
0020 #include <linux/netdevice.h>
0021 #include <linux/string.h>
0022 #include <net/neighbour.h>
0023 #include <net/dst.h>
0024 #include <net/flow.h>
0025
0026 #include <linux/uaccess.h>
0027
0028 #include <net/dn.h>
0029 #include <net/dn_dev.h>
0030 #include <net/dn_route.h>
0031
0032
0033 int decnet_debug_level;
0034 int decnet_time_wait = 30;
0035 int decnet_dn_count = 1;
0036 int decnet_di_count = 3;
0037 int decnet_dr_count = 3;
0038 int decnet_log_martians = 1;
0039 int decnet_no_fc_max_cwnd = NSP_MIN_WINDOW;
0040
0041 /* Reasonable defaults, I hope, based on tcp's defaults */
0042 long sysctl_decnet_mem[3] = { 768 << 3, 1024 << 3, 1536 << 3 };
0043 int sysctl_decnet_wmem[3] = { 4 * 1024, 16 * 1024, 128 * 1024 };
0044 int sysctl_decnet_rmem[3] = { 4 * 1024, 87380, 87380 * 2 };
0045
0046 #ifdef CONFIG_SYSCTL
0047 extern int decnet_dst_gc_interval;
0048 static int min_decnet_time_wait[] = { 5 };
0049 static int max_decnet_time_wait[] = { 600 };
0050 static int min_state_count[] = { 1 };
0051 static int max_state_count[] = { NSP_MAXRXTSHIFT };
0052 static int min_decnet_dst_gc_interval[] = { 1 };
0053 static int max_decnet_dst_gc_interval[] = { 60 };
0054 static int min_decnet_no_fc_max_cwnd[] = { NSP_MIN_WINDOW };
0055 static int max_decnet_no_fc_max_cwnd[] = { NSP_MAX_WINDOW };
0056 static char node_name[7] = "???";
0057
0058 static struct ctl_table_header *dn_table_header = NULL;
0059
0060 /*
0061  * ctype.h :-)
0062  */
0063 #define ISNUM(x) (((x) >= '0') && ((x) <= '9'))
0064 #define ISLOWER(x) (((x) >= 'a') && ((x) <= 'z'))
0065 #define ISUPPER(x) (((x) >= 'A') && ((x) <= 'Z'))
0066 #define ISALPHA(x) (ISLOWER(x) || ISUPPER(x))
0067 #define INVALID_END_CHAR(x) (ISNUM(x) || ISALPHA(x))
0068
0069 static void strip_it(char *str)
0070 {
0071     for(;;) {
0072         switch (*str) {
0073         case ' ':
0074         case '\n':
0075         case '\r':
0076         case ':':
0077             *str = 0;
0078             fallthrough;
0079         case 0:
0080             return;
0081         }
0082         str++;
0083     }
0084 }
0085
0086 /*
0087  * Simple routine to parse an ascii DECnet address
0088  * into a network order address.
0089  */
0090 static int parse_addr(__le16 *addr, char *str)
0091 {
0092     __u16 area, node;
0093
0094     while(*str && !ISNUM(*str)) str++;
0095
0096     if (*str == 0)
0097         return -1;
0098
0099     area = (*str++ - '0');
0100     if (ISNUM(*str)) {
0101         area *= 10;
0102         area += (*str++ - '0');
0103     }
0104
0105     if (*str++ != '.')
0106         return -1;
0107
0108     if (!ISNUM(*str))
0109         return -1;
0110
0111     node = *str++ - '0';
0112     if (ISNUM(*str)) {
0113         node *= 10;
0114         node += (*str++ - '0');
0115     }
0116     if (ISNUM(*str)) {
0117         node *= 10;
0118         node += (*str++ - '0');
0119     }
0120     if (ISNUM(*str)) {
0121         node *= 10;
0122         node += (*str++ - '0');
0123     }
0124
0125     if ((node > 1023) || (area > 63))
0126         return -1;
0127
0128     if (INVALID_END_CHAR(*str))
0129         return -1;
0130
0131     *addr = cpu_to_le16((area << 10) | node);
0132
0133     return 0;
0134 }
0135
0136 static int dn_node_address_handler(struct ctl_table *table, int write,
0137         void *buffer, size_t *lenp, loff_t *ppos)
0138 {
0139     char addr[DN_ASCBUF_LEN];
0140     size_t len;
0141     __le16 dnaddr;
0142
0143     if (!*lenp || (*ppos && !write)) {
0144         *lenp = 0;
0145         return 0;
0146     }
0147
0148     if (write) {
0149         len = (*lenp < DN_ASCBUF_LEN) ? *lenp : (DN_ASCBUF_LEN-1);
0150         memcpy(addr, buffer, len);
0151         addr[len] = 0;
0152         strip_it(addr);
0153
0154         if (parse_addr(&dnaddr, addr))
0155             return -EINVAL;
0156
0157         dn_dev_devices_off();
0158
0159         decnet_address = dnaddr;
0160
0161         dn_dev_devices_on();
0162
0163         *ppos += len;
0164
0165         return 0;
0166     }
0167
0168     dn_addr2asc(le16_to_cpu(decnet_address), addr);
0169     len = strlen(addr);
0170     addr[len++] = '\n';
0171
0172     if (len > *lenp)
0173         len = *lenp;
0174     memcpy(buffer, addr, len);
0175     *lenp = len;
0176     *ppos += len;
0177
0178     return 0;
0179 }
0180
0181 static int dn_def_dev_handler(struct ctl_table *table, int write,
0182         void *buffer, size_t *lenp, loff_t *ppos)
0183 {
0184     size_t len;
0185     struct net_device *dev;
0186     char devname[17];
0187
0188     if (!*lenp || (*ppos && !write)) {
0189         *lenp = 0;
0190         return 0;
0191     }
0192
0193     if (write) {
0194         if (*lenp > 16)
0195             return -E2BIG;
0196
0197         memcpy(devname, buffer, *lenp);
0198         devname[*lenp] = 0;
0199         strip_it(devname);
0200
0201         dev = dev_get_by_name(&init_net, devname);
0202         if (dev == NULL)
0203             return -ENODEV;
0204
0205         if (dev->dn_ptr == NULL) {
0206             dev_put(dev);
0207             return -ENODEV;
0208         }
0209
0210         if (dn_dev_set_default(dev, 1)) {
0211             dev_put(dev);
0212             return -ENODEV;
0213         }
0214         *ppos += *lenp;
0215
0216         return 0;
0217     }
0218
0219     dev = dn_dev_get_default();
0220     if (dev == NULL) {
0221         *lenp = 0;
0222         return 0;
0223     }
0224
0225     strcpy(devname, dev->name);
0226     dev_put(dev);
0227     len = strlen(devname);
0228     devname[len++] = '\n';
0229
0230     if (len > *lenp) len = *lenp;
0231
0232     memcpy(buffer, devname, len);
0233     *lenp = len;
0234     *ppos += len;
0235
0236     return 0;
0237 }
0238
0239 static struct ctl_table dn_table[] = {
0240     {
0241         .procname = "node_address",
0242         .maxlen = 7,
0243         .mode = 0644,
0244         .proc_handler = dn_node_address_handler,
0245     },
0246     {
0247         .procname = "node_name",
0248         .data = node_name,
0249         .maxlen = 7,
0250         .mode = 0644,
0251         .proc_handler = proc_dostring,
0252     },
0253     {
0254         .procname = "default_device",
0255         .maxlen = 16,
0256         .mode = 0644,
0257         .proc_handler = dn_def_dev_handler,
0258     },
0259     {
0260         .procname = "time_wait",
0261         .data = &decnet_time_wait,
0262         .maxlen = sizeof(int),
0263         .mode = 0644,
0264         .proc_handler = proc_dointvec_minmax,
0265         .extra1 = &min_decnet_time_wait,
0266         .extra2 = &max_decnet_time_wait
0267     },
0268     {
0269         .procname = "dn_count",
0270         .data = &decnet_dn_count,
0271         .maxlen = sizeof(int),
0272         .mode = 0644,
0273         .proc_handler = proc_dointvec_minmax,
0274         .extra1 = &min_state_count,
0275         .extra2 = &max_state_count
0276     },
0277     {
0278         .procname = "di_count",
0279         .data = &decnet_di_count,
0280         .maxlen = sizeof(int),
0281         .mode = 0644,
0282         .proc_handler = proc_dointvec_minmax,
0283         .extra1 = &min_state_count,
0284         .extra2 = &max_state_count
0285     },
0286     {
0287         .procname = "dr_count",
0288         .data = &decnet_dr_count,
0289         .maxlen = sizeof(int),
0290         .mode = 0644,
0291         .proc_handler = proc_dointvec_minmax,
0292         .extra1 = &min_state_count,
0293         .extra2 = &max_state_count
0294     },
0295     {
0296         .procname = "dst_gc_interval",
0297         .data = &decnet_dst_gc_interval,
0298         .maxlen = sizeof(int),
0299         .mode = 0644,
0300         .proc_handler = proc_dointvec_minmax,
0301         .extra1 = &min_decnet_dst_gc_interval,
0302         .extra2 = &max_decnet_dst_gc_interval
0303     },
0304     {
0305         .procname = "no_fc_max_cwnd",
0306         .data = &decnet_no_fc_max_cwnd,
0307         .maxlen = sizeof(int),
0308         .mode = 0644,
0309         .proc_handler = proc_dointvec_minmax,
0310         .extra1 = &min_decnet_no_fc_max_cwnd,
0311         .extra2 = &max_decnet_no_fc_max_cwnd
0312     },
0313        {
0314         .procname = "decnet_mem",
0315         .data = &sysctl_decnet_mem,
0316         .maxlen = sizeof(sysctl_decnet_mem),
0317         .mode = 0644,
0318         .proc_handler = proc_doulongvec_minmax
0319     },
0320     {
0321         .procname = "decnet_rmem",
0322         .data = &sysctl_decnet_rmem,
0323         .maxlen = sizeof(sysctl_decnet_rmem),
0324         .mode = 0644,
0325         .proc_handler = proc_dointvec,
0326     },
0327     {
0328         .procname = "decnet_wmem",
0329         .data = &sysctl_decnet_wmem,
0330         .maxlen = sizeof(sysctl_decnet_wmem),
0331         .mode = 0644,
0332         .proc_handler = proc_dointvec,
0333     },
0334     {
0335         .procname = "debug",
0336         .data = &decnet_debug_level,
0337         .maxlen = sizeof(int),
0338         .mode = 0644,
0339         .proc_handler = proc_dointvec,
0340     },
0341     { }
0342 };
0343
0344 void dn_register_sysctl(void)
0345 {
0346     dn_table_header = register_net_sysctl(&init_net, "net/decnet", dn_table);
0347 }
0348
0349 void dn_unregister_sysctl(void)
0350 {
0351     unregister_net_sysctl_table(dn_table_header);
0352 }
0353
0354 #else  /* CONFIG_SYSCTL */
0355 void dn_unregister_sysctl(void)
0356 {
0357 }
0358 void dn_register_sysctl(void)
0359 {
0360 }
0361
0362 #endif