1 files changed, 273 insertions, 0 deletions
diff --git a/tools/testing/selftests/net/tcp_ao/lib/proc.c b/tools/testing/selftests/net/tcp_ao/lib/proc.c
new file mode 100644
index 000000000000..2fb6dd8adba6
--- /dev/null
+++ b/tools/testing/selftests/net/tcp_ao/lib/proc.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <inttypes.h>
+#include <pthread.h>
+#include <stdio.h>
+#include "../../../../../include/linux/compiler.h"
+#include "../../../../../include/linux/kernel.h"
+#include "aolib.h"
+
+struct netstat_counter {
+	uint64_t val;
+	char *name;
+};
+
+struct netstat {
+	char *header_name;
+	struct netstat *next;
+	size_t counters_nr;
+	struct netstat_counter *counters;
+};
+
+static struct netstat *lookup_type(struct netstat *ns,
+		const char *type, size_t len)
+{
+	while (ns != NULL) {
+		size_t cmp = max(len, strlen(ns->header_name));
+
+		if (!strncmp(ns->header_name, type, cmp))
+			return ns;
+		ns = ns->next;
+	}
+	return NULL;
+}
+
+static struct netstat *lookup_get(struct netstat *ns,
+				  const char *type, const size_t len)
+{
+	struct netstat *ret;
+
+	ret = lookup_type(ns, type, len);
+	if (ret != NULL)
+		return ret;
+
+	ret = malloc(sizeof(struct netstat));
+	if (!ret)
+		test_error("malloc()");
+
+	ret->header_name = strndup(type, len);
+	if (ret->header_name == NULL)
+		test_error("strndup()");
+	ret->next = ns;
+	ret->counters_nr = 0;
+	ret->counters = NULL;
+
+	return ret;
+}
+
+static struct netstat *lookup_get_column(struct netstat *ns, const char *line)
+{
+	char *column;
+
+	column = strchr(line, ':');
+	if (!column)
+		test_error("can't parse netstat file");
+
+	return lookup_get(ns, line, column - line);
+}
+
+static void netstat_read_type(FILE *fnetstat, struct netstat **dest, char *line)
+{
+	struct netstat *type = lookup_get_column(*dest, line);
+	const char *pos = line;
+	size_t i, nr_elems = 0;
+	char tmp;
+
+	while ((pos = strchr(pos, ' '))) {
+		nr_elems++;
+		pos++;
+	}
+
+	*dest = type;
+	type->counters = reallocarray(type->counters,
+				type->counters_nr + nr_elems,
+				sizeof(struct netstat_counter));
+	if (!type->counters)
+		test_error("reallocarray()");
+
+	pos = strchr(line, ' ') + 1;
+
+	if (fscanf(fnetstat, type->header_name) == EOF)
+		test_error("fscanf(%s)", type->header_name);
+	if (fread(&tmp, 1, 1, fnetstat) != 1 || tmp != ':')
+		test_error("Unexpected netstat format (%c)", tmp);
+
+	for (i = type->counters_nr; i < type->counters_nr + nr_elems; i++) {
+		struct netstat_counter *nc = &type->counters[i];
+		const char *new_pos = strchr(pos, ' ');
+		const char *fmt = " %" PRIu64;
+
+		if (new_pos == NULL)
+			new_pos = strchr(pos, '\n');
+
+		nc->name = strndup(pos, new_pos - pos);
+		if (nc->name == NULL)
+			test_error("strndup()");
+
+		if (unlikely(!strcmp(nc->name, "MaxConn")))
+			fmt = " %" PRId64; /* MaxConn is signed, RFC 2012 */
+		if (fscanf(fnetstat, fmt, &nc->val) != 1)
+			test_error("fscanf(%s)", nc->name);
+		pos = new_pos + 1;
+	}
+	type->counters_nr += nr_elems;
+
+	if (fread(&tmp, 1, 1, fnetstat) != 1 || tmp != '\n')
+		test_error("Unexpected netstat format");
+}
+
+static const char *snmp6_name = "Snmp6";
+static void snmp6_read(FILE *fnetstat, struct netstat **dest)
+{
+	struct netstat *type = lookup_get(*dest, snmp6_name, strlen(snmp6_name));
+	char *counter_name;
+	size_t i;
+
+	for (i = type->counters_nr;; i++) {
+		struct netstat_counter *nc;
+		uint64_t counter;
+
+		if (fscanf(fnetstat, "%ms", &counter_name) == EOF)
+			break;
+		if (fscanf(fnetstat, "%" PRIu64, &counter) == EOF)
+			test_error("Unexpected snmp6 format");
+		type->counters = reallocarray(type->counters, i + 1,
+					sizeof(struct netstat_counter));
+		if (!type->counters)
+			test_error("reallocarray()");
+		nc = &type->counters[i];
+		nc->name = counter_name;
+		nc->val = counter;
+	}
+	type->counters_nr = i;
+	*dest = type;
+}
+
+struct netstat *netstat_read(void)
+{
+	struct netstat *ret = 0;
+	size_t line_sz = 0;
+	char *line = NULL;
+	FILE *fnetstat;
+
+	/*
+	 * Opening thread-self instead of /proc/net/... as the latter
+	 * points to /proc/self/net/ which instantiates thread-leader's
+	 * net-ns, see:
+	 * commit 155134fef2b6 ("Revert "proc: Point /proc/{mounts,net} at..")
+	 */
+	errno = 0;
+	fnetstat = fopen("/proc/thread-self/net/netstat", "r");
+	if (fnetstat == NULL)
+		test_error("failed to open /proc/net/netstat");
+
+	while (getline(&line, &line_sz, fnetstat) != -1)
+		netstat_read_type(fnetstat, &ret, line);
+	fclose(fnetstat);
+
+	errno = 0;
+	fnetstat = fopen("/proc/thread-self/net/snmp", "r");
+	if (fnetstat == NULL)
+		test_error("failed to open /proc/net/snmp");
+
+	while (getline(&line, &line_sz, fnetstat) != -1)
+		netstat_read_type(fnetstat, &ret, line);
+	fclose(fnetstat);
+
+	errno = 0;
+	fnetstat = fopen("/proc/thread-self/net/snmp6", "r");
+	if (fnetstat == NULL)
+		test_error("failed to open /proc/net/snmp6");
+
+	snmp6_read(fnetstat, &ret);
+	fclose(fnetstat);
+
+	free(line);
+	return ret;
+}
+
+void netstat_free(struct netstat *ns)
+{
+	while (ns != NULL) {
+		struct netstat *prev = ns;
+		size_t i;
+
+		free(ns->header_name);
+		for (i = 0; i < ns->counters_nr; i++)
+			free(ns->counters[i].name);
+		free(ns->counters);
+		ns = ns->next;
+		free(prev);
+	}
+}
+
+static inline void
+__netstat_print_diff(uint64_t a, struct netstat *nsb, size_t i)
+{
+	if (unlikely(!strcmp(nsb->header_name, "MaxConn"))) {
+		test_print("%8s %25s: %" PRId64 " => %" PRId64,
+				nsb->header_name, nsb->counters[i].name,
+				a, nsb->counters[i].val);
+		return;
+	}
+
+	test_print("%8s %25s: %" PRIu64 " => %" PRIu64, nsb->header_name,
+			nsb->counters[i].name, a, nsb->counters[i].val);
+}
+
+void netstat_print_diff(struct netstat *nsa, struct netstat *nsb)
+{
+	size_t i, j;
+
+	while (nsb != NULL) {
+		if (unlikely(strcmp(nsb->header_name, nsa->header_name))) {
+			for (i = 0; i < nsb->counters_nr; i++)
+				__netstat_print_diff(0, nsb, i);
+			nsb = nsb->next;
+			continue;
+		}
+
+		if (nsb->counters_nr < nsa->counters_nr)
+			test_error("Unexpected: some counters disappeared!");
+
+		for (j = 0, i = 0; i < nsb->counters_nr; i++) {
+			if (strcmp(nsb->counters[i].name, nsa->counters[j].name)) {
+				__netstat_print_diff(0, nsb, i);
+				continue;
+			}
+
+			if (nsa->counters[j].val == nsb->counters[i].val) {
+				j++;
+				continue;
+			}
+
+			__netstat_print_diff(nsa->counters[j].val, nsb, i);
+			j++;
+		}
+		if (j != nsa->counters_nr)
+			test_error("Unexpected: some counters disappeared!");
+
+		nsb = nsb->next;
+		nsa = nsa->next;
+	}
+}
+
+uint64_t netstat_get(struct netstat *ns, const char *name, bool *not_found)
+{
+	if (not_found)
+		*not_found = false;
+
+	while (ns != NULL) {
+		size_t i;
+
+		for (i = 0; i < ns->counters_nr; i++) {
+			if (!strcmp(name, ns->counters[i].name))
+				return ns->counters[i].val;
+		}
+
+		ns = ns->next;
+	}
+
+	if (not_found)
+		*not_found = true;
+	return 0;
+}