net: implement SO_TXREHASH socket option support

* src/xlat/sock_options.in (SO_TXREHASH): New constant, introduced
by Linux commit v5.18-rc1~136^2~484^2~3.
* src/xlat/sockopt_txrehash_vals.in: New file.
* src/net.c: Include "xlat/sockopt_txrehash_vals.h".
(print_txrehash): New function.
(print_getsockopt, print_setsockopt) <case SO_TXREHASH>: Call
print_txrehash.
* tests/sockopt-sol_socket.c: Add checks for SO_TXREHASH decoding.
* NEWS: Mention it.

5 files changed, 70 insertions, 13 deletions

diff --git a/NEWS b/NEWS
index 5bd64ce02..5c3a5af0b 100644
--- a/NEWS
+++ b/NEWS
@@ -8,6 +8,7 @@ Noteworthy changes in release ?.?? (????-??-??)
 
 * Improvements
   * Implemented printing of Unix socket sun_path field's SELinux context.
+  * Implemented decoding of SO_TXREHASH socket option.
   * Implemented decoding of IFLA_TSO_MAX_SIZE, IFLA_TSO_MAX_SEGS,
     NDA_FDB_EXT_ATTRS, NDA_FLAGS_EXT, NDA_NDM_FLAGS_MASK,
     and NDA_NDM_STATE_MASK netlink attributes.
diff --git a/src/net.c b/src/net.c
index 43db0d8c5..a6ff1d653 100644
--- a/src/net.c
+++ b/src/net.c
@@ -706,6 +706,29 @@ print_get_error(struct tcb *const tcp, const kernel_ulong_t addr,
 	tprint_indirect_end();
 }
 
+#include "xlat/sockopt_txrehash_vals.h"
+
+static void
+print_txrehash(struct tcb *const tcp, const kernel_ulong_t addr, const int len)
+{
+	int val = 0;
+
+	if (len < (int) sizeof(val)) {
+		if (entering(tcp))
+			printaddr(addr);
+		else
+			printstrn(tcp, addr, len);
+		return;
+	}
+
+	if (umove_or_printaddr(tcp, addr, &val))
+		return;
+
+	tprint_indirect_begin();
+	printxval_d(sockopt_txrehash_vals, val, "SOCK_TXREHASH_???");
+	tprint_indirect_end();
+}
+
 static void
 print_tpacket_stats(struct tcb *const tcp, const kernel_ulong_t addr,
 		    unsigned int len)
@@ -796,6 +819,9 @@ print_getsockopt(struct tcb *const tcp, const unsigned int level,
 		case SO_ERROR:
 			print_get_error(tcp, addr, rlen);
 			return;
+		case SO_TXREHASH:
+			print_txrehash(tcp, addr, rlen);
+			return;
 
 		/* All known int-like options */
 		case SO_DEBUG:
@@ -1062,6 +1088,9 @@ print_setsockopt(struct tcb *const tcp, const unsigned int level,
 			else
 				printaddr(addr);
 			return;
+		case SO_TXREHASH:
+			print_txrehash(tcp, addr, len);
+			return;
 
 		/* All known int-like options */
 		case SO_DEBUG:
diff --git a/src/xlat/sock_options.in b/src/xlat/sock_options.in
index 942cbc7db..839441912 100755
--- a/src/xlat/sock_options.in
+++ b/src/xlat/sock_options.in
@@ -553,6 +553,14 @@ SO_RESERVE_MEM		73
 #endif
 
 #if defined __sparc__
+SO_TXREHASH		83
+#elif defined __hppa__
+SO_TXREHASH		16456
+#else
+SO_TXREHASH		74
+#endif
+
+#if defined __sparc__
 SO_RCVMARK		84
 #elif defined __hppa__
 SO_RCVMARK		16457
diff --git a/src/xlat/sockopt_txrehash_vals.in b/src/xlat/sockopt_txrehash_vals.in
new file mode 100644
index 000000000..15c9e59e0
--- /dev/null
+++ b/src/xlat/sockopt_txrehash_vals.in
@@ -0,0 +1,3 @@
+SOCK_TXREHASH_DISABLED  0
+SOCK_TXREHASH_ENABLED   1
+SOCK_TXREHASH_DEFAULT   255
diff --git a/tests/sockopt-sol_socket.c b/tests/sockopt-sol_socket.c
index d2c4254a5..7aa58cb15 100644
--- a/tests/sockopt-sol_socket.c
+++ b/tests/sockopt-sol_socket.c
@@ -47,6 +47,19 @@ set_sockopt(int fd, int name, void *val, socklen_t len)
 	return rc;
 }
 
+static void
+print_optval(int val, const struct intstr *vecs, size_t vecs_sz)
+{
+	for (size_t k = 0; k < vecs_sz; k++) {
+		if (vecs[k].val == val) {
+			printf("[%s]", vecs[k].str);
+			return;
+		}
+	}
+
+	printf("[%d]", val);
+}
+
 int
 main(void)
 {
@@ -56,6 +69,16 @@ main(void)
 		{ ARG_STR(1234567890) },
 		{ ARG_STR(-1234567890) },
 	};
+	static const struct intstr txrehash_vecs[] = {
+		{ ARG_XLAT_KNOWN(0, "SOCK_TXREHASH_DISABLED") },
+		{ ARG_XLAT_KNOWN(1, "SOCK_TXREHASH_ENABLED") },
+		{ ARG_XLAT_UNKNOWN(2, "SOCK_TXREHASH_???") },
+		{ ARG_XLAT_UNKNOWN(254, "SOCK_TXREHASH_???") },
+		{ ARG_XLAT_KNOWN(255, "SOCK_TXREHASH_DEFAULT") },
+		{ ARG_XLAT_UNKNOWN(256, "SOCK_TXREHASH_???") },
+		{ ARG_XLAT_UNKNOWN(511, "SOCK_TXREHASH_???") },
+		{ ARG_XLAT_UNKNOWN(-1, "SOCK_TXREHASH_???") },
+	};
 	static const struct {
 		int val;
 		const char *str;
@@ -133,6 +156,7 @@ main(void)
 		{ ARG_STR(SO_NETNS_COOKIE), /* TODO */ },
 		{ ARG_STR(SO_BUF_LOCK), /* TODO */ },
 		{ ARG_STR(SO_RESERVE_MEM), .optsz = sizeof(int) },
+		{ ARG_STR(SO_TXREHASH), ARRSZ_PAIR(txrehash_vecs), sizeof(int) },
 		{ ARG_STR(SO_RCVMARK), .optsz = sizeof(int) },
 		{ 76, NULL },
 		{ -1, NULL },
@@ -176,10 +200,8 @@ main(void)
 			printf("g%s", pfx_str);
 			if (rc < 0)
 				printf("%p", val);
-			else if (!rc)
-				printf("[%d]", *val);
 			else
-				printf("[%s]", vecs[j].str);
+				print_optval(*val, vecs, vecs_sz);
 			printf(", [%d]) = %s" INJSTR "\n", *len, errstr);
 
 			/* optlen larger than accessible memory */
@@ -188,10 +210,8 @@ main(void)
 			printf("g%s", pfx_str);
 			if (rc < 0 || (!names[i].optsz && *len > sizeof(*val)))
 				printf("%p", val);
-			else if (rc > 0)
-				printf("[%s]", vecs[j].str);
 			else
-				printf("[%d]", *val);
+				print_optval(*val, vecs, vecs_sz);
 			printf(", [%d", (int) sizeof(*val) + 1);
 			if ((int) sizeof(*val) + 1 != *len)
 				printf(" => %d", *len);
@@ -205,14 +225,10 @@ main(void)
 			if (rc < 0) {
 				printf("%p", bigval);
 			} else {
-				if (*len == sizeof(*val) || names[i].optsz) {
-					if (rc)
-						printf("[%s]", vecs[j].str);
-					else
-						printf("[%d]", *val);
-				} else {
+				if (*len == sizeof(*val) || names[i].optsz)
+					print_optval(*val, vecs, vecs_sz);
+				else
 					print_quoted_memory(bigval, *len);
-				}
 			}
 			printf(", [%d", (int) sizeof(*val) + 1);
 			if ((int) sizeof(*val) + 1 != *len)