tools/testing/selftests/net/tcp_ao/lib/proc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <inttypes.h>
   3 #include <pthread.h>
   4 #include <stdio.h>
   5 #include "../../../../../include/linux/compiler.h"
   6 #include "../../../../../include/linux/kernel.h"
   7 #include "aolib.h"
   8
   9 struct netstat_counter {
  10         uint64_t val;
  11         char *name;
  12 };
  13
  14 struct netstat {
  15         char *header_name;
  16         struct netstat *next;
  17         size_t counters_nr;
  18         struct netstat_counter *counters;
  19 };
  20
  21 static struct netstat *lookup_type(struct netstat *ns,
  22                 const char *type, size_t len)
  23 {
  24         while (ns != NULL) {
  25                 size_t cmp = max(len, strlen(ns->header_name));
  26
  27                 if (!strncmp(ns->header_name, type, cmp))
  28                         return ns;
  29                 ns = ns->next;
  30         }
  31         return NULL;
  32 }
  33
  34 static struct netstat *lookup_get(struct netstat *ns,
  35                                   const char *type, const size_t len)
  36 {
  37         struct netstat *ret;
  38
  39         ret = lookup_type(ns, type, len);
  40         if (ret != NULL)
  41                 return ret;
  42
  43         ret = malloc(sizeof(struct netstat));
  44         if (!ret)
  45                 test_error("malloc()");
  46
  47         ret->header_name = strndup(type, len);
  48         if (ret->header_name == NULL)
  49                 test_error("strndup()");
  50         ret->next = ns;
  51         ret->counters_nr = 0;
  52         ret->counters = NULL;
  53
  54         return ret;
  55 }
  56
  57 static struct netstat *lookup_get_column(struct netstat *ns, const char *line)
  58 {
  59         char *column;
  60
  61         column = strchr(line, ':');
  62         if (!column)
  63                 test_error("can't parse netstat file");
  64
  65         return lookup_get(ns, line, column - line);
  66 }
  67
  68 static void netstat_read_type(FILE *fnetstat, struct netstat **dest, char *line)
  69 {
  70         struct netstat *type = lookup_get_column(*dest, line);
  71         const char *pos = line;
  72         size_t i, nr_elems = 0;
  73         char tmp;
  74
  75         while ((pos = strchr(pos, ' '))) {
  76                 nr_elems++;
  77                 pos++;
  78         }
  79
  80         *dest = type;
  81         type->counters = reallocarray(type->counters,
  82                                 type->counters_nr + nr_elems,
  83                                 sizeof(struct netstat_counter));
  84         if (!type->counters)
  85                 test_error("reallocarray()");
  86
  87         pos = strchr(line, ' ') + 1;
  88
  89         if (fscanf(fnetstat, "%[^ :]", type->header_name) == EOF)
  90                 test_error("fscanf(%s)", type->header_name);
  91         if (fread(&tmp, 1, 1, fnetstat) != 1 || tmp != ':')
  92                 test_error("Unexpected netstat format (%c)", tmp);
  93
  94         for (i = type->counters_nr; i < type->counters_nr + nr_elems; i++) {
  95                 struct netstat_counter *nc = &type->counters[i];
  96                 const char *new_pos = strchr(pos, ' ');
  97                 const char *fmt = " %" PRIu64;
  98
  99                 if (new_pos == NULL)
 100                         new_pos = strchr(pos, '\n');
 101
 102                 nc->name = strndup(pos, new_pos - pos);
 103                 if (nc->name == NULL)
 104                         test_error("strndup()");
 105
 106                 if (unlikely(!strcmp(nc->name, "MaxConn")))
 107                         fmt = " %" PRId64; /* MaxConn is signed, RFC 2012 */
 108                 if (fscanf(fnetstat, fmt, &nc->val) != 1)
 109                         test_error("fscanf(%s)", nc->name);
 110                 pos = new_pos + 1;
 111         }
 112         type->counters_nr += nr_elems;
 113
 114         if (fread(&tmp, 1, 1, fnetstat) != 1 || tmp != '\n')
 115                 test_error("Unexpected netstat format");
 116 }
 117
 118 static const char *snmp6_name = "Snmp6";
 119 static void snmp6_read(FILE *fnetstat, struct netstat **dest)
 120 {
 121         struct netstat *type = lookup_get(*dest, snmp6_name, strlen(snmp6_name));
 122         char *counter_name;
 123         size_t i;
 124
 125         for (i = type->counters_nr;; i++) {
 126                 struct netstat_counter *nc;
 127                 uint64_t counter;
 128
 129                 if (fscanf(fnetstat, "%ms", &counter_name) == EOF)
 130                         break;
 131                 if (fscanf(fnetstat, "%" PRIu64, &counter) == EOF)
 132                         test_error("Unexpected snmp6 format");
 133                 type->counters = reallocarray(type->counters, i + 1,
 134                                         sizeof(struct netstat_counter));
 135                 if (!type->counters)
 136                         test_error("reallocarray()");
 137                 nc = &type->counters[i];
 138                 nc->name = counter_name;
 139                 nc->val = counter;
 140         }
 141         type->counters_nr = i;
 142         *dest = type;
 143 }
 144
 145 struct netstat *netstat_read(void)
 146 {
 147         struct netstat *ret = 0;
 148         size_t line_sz = 0;
 149         char *line = NULL;
 150         FILE *fnetstat;
 151
 152         /*
 153          * Opening thread-self instead of /proc/net/... as the latter
 154          * points to /proc/self/net/ which instantiates thread-leader's
 155          * net-ns, see:
 156          * commit 155134fef2b6 ("Revert "proc: Point /proc/{mounts,net} at..")
 157          */
 158         errno = 0;
 159         fnetstat = fopen("/proc/thread-self/net/netstat", "r");
 160         if (fnetstat == NULL)
 161                 test_error("failed to open /proc/net/netstat");
 162
 163         while (getline(&line, &line_sz, fnetstat) != -1)
 164                 netstat_read_type(fnetstat, &ret, line);
 165         fclose(fnetstat);
 166
 167         errno = 0;
 168         fnetstat = fopen("/proc/thread-self/net/snmp", "r");
 169         if (fnetstat == NULL)
 170                 test_error("failed to open /proc/net/snmp");
 171
 172         while (getline(&line, &line_sz, fnetstat) != -1)
 173                 netstat_read_type(fnetstat, &ret, line);
 174         fclose(fnetstat);
 175
 176         errno = 0;
 177         fnetstat = fopen("/proc/thread-self/net/snmp6", "r");
 178         if (fnetstat == NULL)
 179                 test_error("failed to open /proc/net/snmp6");
 180
 181         snmp6_read(fnetstat, &ret);
 182         fclose(fnetstat);
 183
 184         free(line);
 185         return ret;
 186 }
 187
 188 void netstat_free(struct netstat *ns)
 189 {
 190         while (ns != NULL) {
 191                 struct netstat *prev = ns;
 192                 size_t i;
 193
 194                 free(ns->header_name);
 195                 for (i = 0; i < ns->counters_nr; i++)
 196                         free(ns->counters[i].name);
 197                 free(ns->counters);
 198                 ns = ns->next;
 199                 free(prev);
 200         }
 201 }
 202
 203 static inline void
 204 __netstat_print_diff(uint64_t a, struct netstat *nsb, size_t i)
 205 {
 206         if (unlikely(!strcmp(nsb->header_name, "MaxConn"))) {
 207                 test_print("%8s %25s: %" PRId64 " => %" PRId64,
 208                                 nsb->header_name, nsb->counters[i].name,
 209                                 a, nsb->counters[i].val);
 210                 return;
 211         }
 212
 213         test_print("%8s %25s: %" PRIu64 " => %" PRIu64, nsb->header_name,
 214                         nsb->counters[i].name, a, nsb->counters[i].val);
 215 }
 216
 217 void netstat_print_diff(struct netstat *nsa, struct netstat *nsb)
 218 {
 219         size_t i, j;
 220
 221         while (nsb != NULL) {
 222                 if (unlikely(strcmp(nsb->header_name, nsa->header_name))) {
 223                         for (i = 0; i < nsb->counters_nr; i++)
 224                                 __netstat_print_diff(0, nsb, i);
 225                         nsb = nsb->next;
 226                         continue;
 227                 }
 228
 229                 if (nsb->counters_nr < nsa->counters_nr)
 230                         test_error("Unexpected: some counters disappeared!");
 231
 232                 for (j = 0, i = 0; i < nsb->counters_nr; i++) {
 233                         if (strcmp(nsb->counters[i].name, nsa->counters[j].name)) {
 234                                 __netstat_print_diff(0, nsb, i);
 235                                 continue;
 236                         }
 237
 238                         if (nsa->counters[j].val == nsb->counters[i].val) {
 239                                 j++;
 240                                 continue;
 241                         }
 242
 243                         __netstat_print_diff(nsa->counters[j].val, nsb, i);
 244                         j++;
 245                 }
 246                 if (j != nsa->counters_nr)
 247                         test_error("Unexpected: some counters disappeared!");
 248
 249                 nsb = nsb->next;
 250                 nsa = nsa->next;
 251         }
 252 }
 253
 254 uint64_t netstat_get(struct netstat *ns, const char *name, bool *not_found)
 255 {
 256         if (not_found)
 257                 *not_found = false;
 258
 259         while (ns != NULL) {
 260                 size_t i;
 261
 262                 for (i = 0; i < ns->counters_nr; i++) {
 263                         if (!strcmp(name, ns->counters[i].name))
 264                                 return ns->counters[i].val;
 265                 }
 266
 267                 ns = ns->next;
 268         }
 269
 270         if (not_found)
 271                 *not_found = true;
 272         return 0;
 273 }