selftests/net: Cover the IP_LOCAL_PORT_RANGE socket option
authorJakub Sitnicki <jakub@cloudflare.com>
Tue, 24 Jan 2023 13:36:44 +0000 (14:36 +0100)
committerJakub Kicinski <kuba@kernel.org>
Thu, 26 Jan 2023 06:45:00 +0000 (22:45 -0800)
Exercise IP_LOCAL_PORT_RANGE socket option in various scenarios:

1. pass invalid values to setsockopt
2. pass a range outside of the per-netns port range
3. configure a single-port range
4. exhaust a configured multi-port range
5. check interaction with late-bind (IP_BIND_ADDRESS_NO_PORT)
6. set then get the per-socket port range

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tools/testing/selftests/net/Makefile
tools/testing/selftests/net/ip_local_port_range.c [new file with mode: 0644]
tools/testing/selftests/net/ip_local_port_range.sh [new file with mode: 0755]

index 47314f0..951bd53 100644 (file)
@@ -45,6 +45,7 @@ TEST_PROGS += arp_ndisc_untracked_subnets.sh
 TEST_PROGS += stress_reuseport_listen.sh
 TEST_PROGS += l2_tos_ttl_inherit.sh
 TEST_PROGS += bind_bhash.sh
+TEST_PROGS += ip_local_port_range.sh
 TEST_PROGS_EXTENDED := in_netns.sh setup_loopback.sh setup_veth.sh
 TEST_PROGS_EXTENDED += toeplitz_client.sh toeplitz.sh
 TEST_GEN_FILES =  socket nettest
@@ -76,6 +77,7 @@ TEST_PROGS += sctp_vrf.sh
 TEST_GEN_FILES += sctp_hello
 TEST_GEN_FILES += csum
 TEST_GEN_FILES += nat6to4.o
+TEST_GEN_FILES += ip_local_port_range
 
 TEST_FILES := settings
 
diff --git a/tools/testing/selftests/net/ip_local_port_range.c b/tools/testing/selftests/net/ip_local_port_range.c
new file mode 100644 (file)
index 0000000..75e3fda
--- /dev/null
@@ -0,0 +1,447 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+// Copyright (c) 2023 Cloudflare
+
+/* Test IP_LOCAL_PORT_RANGE socket option: IPv4 + IPv6, TCP + UDP.
+ *
+ * Tests assume that net.ipv4.ip_local_port_range is [40000, 49999].
+ * Don't run these directly but with ip_local_port_range.sh script.
+ */
+
+#include <fcntl.h>
+#include <netinet/ip.h>
+
+#include "../kselftest_harness.h"
+
+#ifndef IP_LOCAL_PORT_RANGE
+#define IP_LOCAL_PORT_RANGE 51
+#endif
+
+static __u32 pack_port_range(__u16 lo, __u16 hi)
+{
+       return (hi << 16) | (lo << 0);
+}
+
+static void unpack_port_range(__u32 range, __u16 *lo, __u16 *hi)
+{
+       *lo = range & 0xffff;
+       *hi = range >> 16;
+}
+
+static int get_so_domain(int fd)
+{
+       int domain, err;
+       socklen_t len;
+
+       len = sizeof(domain);
+       err = getsockopt(fd, SOL_SOCKET, SO_DOMAIN, &domain, &len);
+       if (err)
+               return -1;
+
+       return domain;
+}
+
+static int bind_to_loopback_any_port(int fd)
+{
+       union {
+               struct sockaddr sa;
+               struct sockaddr_in v4;
+               struct sockaddr_in6 v6;
+       } addr;
+       socklen_t addr_len;
+
+       memset(&addr, 0, sizeof(addr));
+       switch (get_so_domain(fd)) {
+       case AF_INET:
+               addr.v4.sin_family = AF_INET;
+               addr.v4.sin_port = htons(0);
+               addr.v4.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+               addr_len = sizeof(addr.v4);
+               break;
+       case AF_INET6:
+               addr.v6.sin6_family = AF_INET6;
+               addr.v6.sin6_port = htons(0);
+               addr.v6.sin6_addr = in6addr_loopback;
+               addr_len = sizeof(addr.v6);
+               break;
+       default:
+               return -1;
+       }
+
+       return bind(fd, &addr.sa, addr_len);
+}
+
+static int get_sock_port(int fd)
+{
+       union {
+               struct sockaddr sa;
+               struct sockaddr_in v4;
+               struct sockaddr_in6 v6;
+       } addr;
+       socklen_t addr_len;
+       int err;
+
+       addr_len = sizeof(addr);
+       memset(&addr, 0, sizeof(addr));
+       err = getsockname(fd, &addr.sa, &addr_len);
+       if (err)
+               return -1;
+
+       switch (addr.sa.sa_family) {
+       case AF_INET:
+               return ntohs(addr.v4.sin_port);
+       case AF_INET6:
+               return ntohs(addr.v6.sin6_port);
+       default:
+               errno = EAFNOSUPPORT;
+               return -1;
+       }
+}
+
+static int get_ip_local_port_range(int fd, __u32 *range)
+{
+       socklen_t len;
+       __u32 val;
+       int err;
+
+       len = sizeof(val);
+       err = getsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &val, &len);
+       if (err)
+               return -1;
+
+       *range = val;
+       return 0;
+}
+
+FIXTURE(ip_local_port_range) {};
+
+FIXTURE_SETUP(ip_local_port_range)
+{
+}
+
+FIXTURE_TEARDOWN(ip_local_port_range)
+{
+}
+
+FIXTURE_VARIANT(ip_local_port_range) {
+       int so_domain;
+       int so_type;
+       int so_protocol;
+};
+
+FIXTURE_VARIANT_ADD(ip_local_port_range, ip4_tcp) {
+       .so_domain      = AF_INET,
+       .so_type        = SOCK_STREAM,
+       .so_protocol    = 0,
+};
+
+FIXTURE_VARIANT_ADD(ip_local_port_range, ip4_udp) {
+       .so_domain      = AF_INET,
+       .so_type        = SOCK_DGRAM,
+       .so_protocol    = 0,
+};
+
+FIXTURE_VARIANT_ADD(ip_local_port_range, ip4_stcp) {
+       .so_domain      = AF_INET,
+       .so_type        = SOCK_STREAM,
+       .so_protocol    = IPPROTO_SCTP,
+};
+
+FIXTURE_VARIANT_ADD(ip_local_port_range, ip6_tcp) {
+       .so_domain      = AF_INET6,
+       .so_type        = SOCK_STREAM,
+       .so_protocol    = 0,
+};
+
+FIXTURE_VARIANT_ADD(ip_local_port_range, ip6_udp) {
+       .so_domain      = AF_INET6,
+       .so_type        = SOCK_DGRAM,
+       .so_protocol    = 0,
+};
+
+FIXTURE_VARIANT_ADD(ip_local_port_range, ip6_stcp) {
+       .so_domain      = AF_INET6,
+       .so_type        = SOCK_STREAM,
+       .so_protocol    = IPPROTO_SCTP,
+};
+
+TEST_F(ip_local_port_range, invalid_option_value)
+{
+       __u16 val16;
+       __u32 val32;
+       __u64 val64;
+       int fd, err;
+
+       fd = socket(variant->so_domain, variant->so_type, variant->so_protocol);
+       ASSERT_GE(fd, 0) TH_LOG("socket failed");
+
+       /* Too few bytes */
+       val16 = 40000;
+       err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &val16, sizeof(val16));
+       EXPECT_TRUE(err) TH_LOG("expected setsockopt(IP_LOCAL_PORT_RANGE) to fail");
+       EXPECT_EQ(errno, EINVAL);
+
+       /* Empty range: low port > high port */
+       val32 = pack_port_range(40222, 40111);
+       err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &val32, sizeof(val32));
+       EXPECT_TRUE(err) TH_LOG("expected setsockopt(IP_LOCAL_PORT_RANGE) to fail");
+       EXPECT_EQ(errno, EINVAL);
+
+       /* Too many bytes */
+       val64 = pack_port_range(40333, 40444);
+       err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &val64, sizeof(val64));
+       EXPECT_TRUE(err) TH_LOG("expected setsockopt(IP_LOCAL_PORT_RANGE) to fail");
+       EXPECT_EQ(errno, EINVAL);
+
+       err = close(fd);
+       ASSERT_TRUE(!err) TH_LOG("close failed");
+}
+
+TEST_F(ip_local_port_range, port_range_out_of_netns_range)
+{
+       const struct test {
+               __u16 range_lo;
+               __u16 range_hi;
+       } tests[] = {
+               { 30000, 39999 }, /* socket range below netns range */
+               { 50000, 59999 }, /* socket range above netns range */
+       };
+       const struct test *t;
+
+       for (t = tests; t < tests + ARRAY_SIZE(tests); t++) {
+               /* Bind a couple of sockets, not just one, to check
+                * that the range wasn't clamped to a single port from
+                * the netns range. That is [40000, 40000] or [49999,
+                * 49999], respectively for each test case.
+                */
+               int fds[2], i;
+
+               TH_LOG("lo %5hu, hi %5hu", t->range_lo, t->range_hi);
+
+               for (i = 0; i < ARRAY_SIZE(fds); i++) {
+                       int fd, err, port;
+                       __u32 range;
+
+                       fd = socket(variant->so_domain, variant->so_type, variant->so_protocol);
+                       ASSERT_GE(fd, 0) TH_LOG("#%d: socket failed", i);
+
+                       range = pack_port_range(t->range_lo, t->range_hi);
+                       err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &range, sizeof(range));
+                       ASSERT_TRUE(!err) TH_LOG("#%d: setsockopt(IP_LOCAL_PORT_RANGE) failed", i);
+
+                       err = bind_to_loopback_any_port(fd);
+                       ASSERT_TRUE(!err) TH_LOG("#%d: bind failed", i);
+
+                       /* Check that socket port range outside of ephemeral range is ignored */
+                       port = get_sock_port(fd);
+                       ASSERT_GE(port, 40000) TH_LOG("#%d: expected port within netns range", i);
+                       ASSERT_LE(port, 49999) TH_LOG("#%d: expected port within netns range", i);
+
+                       fds[i] = fd;
+               }
+
+               for (i = 0; i < ARRAY_SIZE(fds); i++)
+                       ASSERT_TRUE(close(fds[i]) == 0) TH_LOG("#%d: close failed", i);
+       }
+}
+
+TEST_F(ip_local_port_range, single_port_range)
+{
+       const struct test {
+               __u16 range_lo;
+               __u16 range_hi;
+               __u16 expected;
+       } tests[] = {
+               /* single port range within ephemeral range */
+               { 45000, 45000, 45000 },
+               /* first port in the ephemeral range (clamp from above) */
+               { 0, 40000, 40000 },
+               /* last port in the ephemeral range (clamp from below)  */
+               { 49999, 0, 49999 },
+       };
+       const struct test *t;
+
+       for (t = tests; t < tests + ARRAY_SIZE(tests); t++) {
+               int fd, err, port;
+               __u32 range;
+
+               TH_LOG("lo %5hu, hi %5hu, expected %5hu",
+                      t->range_lo, t->range_hi, t->expected);
+
+               fd = socket(variant->so_domain, variant->so_type, variant->so_protocol);
+               ASSERT_GE(fd, 0) TH_LOG("socket failed");
+
+               range = pack_port_range(t->range_lo, t->range_hi);
+               err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &range, sizeof(range));
+               ASSERT_TRUE(!err) TH_LOG("setsockopt(IP_LOCAL_PORT_RANGE) failed");
+
+               err = bind_to_loopback_any_port(fd);
+               ASSERT_TRUE(!err) TH_LOG("bind failed");
+
+               port = get_sock_port(fd);
+               ASSERT_EQ(port, t->expected) TH_LOG("unexpected local port");
+
+               err = close(fd);
+               ASSERT_TRUE(!err) TH_LOG("close failed");
+       }
+}
+
+TEST_F(ip_local_port_range, exhaust_8_port_range)
+{
+       __u8 port_set = 0;
+       int i, fd, err;
+       __u32 range;
+       __u16 port;
+       int fds[8];
+
+       for (i = 0; i < ARRAY_SIZE(fds); i++) {
+               fd = socket(variant->so_domain, variant->so_type, variant->so_protocol);
+               ASSERT_GE(fd, 0) TH_LOG("socket failed");
+
+               range = pack_port_range(40000, 40007);
+               err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &range, sizeof(range));
+               ASSERT_TRUE(!err) TH_LOG("setsockopt(IP_LOCAL_PORT_RANGE) failed");
+
+               err = bind_to_loopback_any_port(fd);
+               ASSERT_TRUE(!err) TH_LOG("bind failed");
+
+               port = get_sock_port(fd);
+               ASSERT_GE(port, 40000) TH_LOG("expected port within sockopt range");
+               ASSERT_LE(port, 40007) TH_LOG("expected port within sockopt range");
+
+               port_set |= 1 << (port - 40000);
+               fds[i] = fd;
+       }
+
+       /* Check that all every port from the test range is in use */
+       ASSERT_EQ(port_set, 0xff) TH_LOG("expected all ports to be busy");
+
+       /* Check that bind() fails because the whole range is busy */
+       fd = socket(variant->so_domain, variant->so_type, variant->so_protocol);
+       ASSERT_GE(fd, 0) TH_LOG("socket failed");
+
+       range = pack_port_range(40000, 40007);
+       err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &range, sizeof(range));
+       ASSERT_TRUE(!err) TH_LOG("setsockopt(IP_LOCAL_PORT_RANGE) failed");
+
+       err = bind_to_loopback_any_port(fd);
+       ASSERT_TRUE(err) TH_LOG("expected bind to fail");
+       ASSERT_EQ(errno, EADDRINUSE);
+
+       err = close(fd);
+       ASSERT_TRUE(!err) TH_LOG("close failed");
+
+       for (i = 0; i < ARRAY_SIZE(fds); i++) {
+               err = close(fds[i]);
+               ASSERT_TRUE(!err) TH_LOG("close failed");
+       }
+}
+
+TEST_F(ip_local_port_range, late_bind)
+{
+       union {
+               struct sockaddr sa;
+               struct sockaddr_in v4;
+               struct sockaddr_in6 v6;
+       } addr;
+       socklen_t addr_len;
+       const int one = 1;
+       int fd, err;
+       __u32 range;
+       __u16 port;
+
+       if (variant->so_protocol == IPPROTO_SCTP)
+               SKIP(return, "SCTP doesn't support IP_BIND_ADDRESS_NO_PORT");
+
+       fd = socket(variant->so_domain, variant->so_type, 0);
+       ASSERT_GE(fd, 0) TH_LOG("socket failed");
+
+       range = pack_port_range(40100, 40199);
+       err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &range, sizeof(range));
+       ASSERT_TRUE(!err) TH_LOG("setsockopt(IP_LOCAL_PORT_RANGE) failed");
+
+       err = setsockopt(fd, SOL_IP, IP_BIND_ADDRESS_NO_PORT, &one, sizeof(one));
+       ASSERT_TRUE(!err) TH_LOG("setsockopt(IP_BIND_ADDRESS_NO_PORT) failed");
+
+       err = bind_to_loopback_any_port(fd);
+       ASSERT_TRUE(!err) TH_LOG("bind failed");
+
+       port = get_sock_port(fd);
+       ASSERT_EQ(port, 0) TH_LOG("getsockname failed");
+
+       /* Invalid destination */
+       memset(&addr, 0, sizeof(addr));
+       switch (variant->so_domain) {
+       case AF_INET:
+               addr.v4.sin_family = AF_INET;
+               addr.v4.sin_port = htons(0);
+               addr.v4.sin_addr.s_addr = htonl(INADDR_ANY);
+               addr_len = sizeof(addr.v4);
+               break;
+       case AF_INET6:
+               addr.v6.sin6_family = AF_INET6;
+               addr.v6.sin6_port = htons(0);
+               addr.v6.sin6_addr = in6addr_any;
+               addr_len = sizeof(addr.v6);
+               break;
+       default:
+               ASSERT_TRUE(false) TH_LOG("unsupported socket domain");
+       }
+
+       /* connect() doesn't need to succeed for late bind to happen */
+       connect(fd, &addr.sa, addr_len);
+
+       port = get_sock_port(fd);
+       ASSERT_GE(port, 40100);
+       ASSERT_LE(port, 40199);
+
+       err = close(fd);
+       ASSERT_TRUE(!err) TH_LOG("close failed");
+}
+
+TEST_F(ip_local_port_range, get_port_range)
+{
+       __u16 lo, hi;
+       __u32 range;
+       int fd, err;
+
+       fd = socket(variant->so_domain, variant->so_type, variant->so_protocol);
+       ASSERT_GE(fd, 0) TH_LOG("socket failed");
+
+       /* Get range before it will be set */
+       err = get_ip_local_port_range(fd, &range);
+       ASSERT_TRUE(!err) TH_LOG("getsockopt(IP_LOCAL_PORT_RANGE) failed");
+
+       unpack_port_range(range, &lo, &hi);
+       ASSERT_EQ(lo, 0) TH_LOG("unexpected low port");
+       ASSERT_EQ(hi, 0) TH_LOG("unexpected high port");
+
+       range = pack_port_range(12345, 54321);
+       err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &range, sizeof(range));
+       ASSERT_TRUE(!err) TH_LOG("setsockopt(IP_LOCAL_PORT_RANGE) failed");
+
+       /* Get range after it has been set */
+       err = get_ip_local_port_range(fd, &range);
+       ASSERT_TRUE(!err) TH_LOG("getsockopt(IP_LOCAL_PORT_RANGE) failed");
+
+       unpack_port_range(range, &lo, &hi);
+       ASSERT_EQ(lo, 12345) TH_LOG("unexpected low port");
+       ASSERT_EQ(hi, 54321) TH_LOG("unexpected high port");
+
+       /* Unset the port range  */
+       range = pack_port_range(0, 0);
+       err = setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &range, sizeof(range));
+       ASSERT_TRUE(!err) TH_LOG("setsockopt(IP_LOCAL_PORT_RANGE) failed");
+
+       /* Get range after it has been unset */
+       err = get_ip_local_port_range(fd, &range);
+       ASSERT_TRUE(!err) TH_LOG("getsockopt(IP_LOCAL_PORT_RANGE) failed");
+
+       unpack_port_range(range, &lo, &hi);
+       ASSERT_EQ(lo, 0) TH_LOG("unexpected low port");
+       ASSERT_EQ(hi, 0) TH_LOG("unexpected high port");
+
+       err = close(fd);
+       ASSERT_TRUE(!err) TH_LOG("close failed");
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/net/ip_local_port_range.sh b/tools/testing/selftests/net/ip_local_port_range.sh
new file mode 100755 (executable)
index 0000000..6c6ad34
--- /dev/null
@@ -0,0 +1,5 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+
+./in_netns.sh \
+  sh -c 'sysctl -q -w net.ipv4.ip_local_port_range="40000 49999" && ./ip_local_port_range'