platform: add NMPGenlFamilyType enum for generic netlink types

The genl types that we care about are well known. Add an enum
for them, so we can do a lookup by index.

To kernel, the corresponding names (like "wireguard") are also well
known. However, the family-id, that we need when using genl are
allocated dynamically. So we need to lookup the family-id, and by having
an enum for the genl type, we can do so generically.

3 files changed, 149 insertions, 0 deletions

diff --git a/src/core/platform/tests/test-platform-general.c b/src/core/platform/tests/test-platform-general.c
index 908ad4dd3e..c18886c96e 100644
--- a/src/core/platform/tests/test-platform-general.c
+++ b/src/core/platform/tests/test-platform-general.c
@@ -788,6 +788,64 @@ test_route_type_is_nodev(void)
 
 /*****************************************************************************/
 
+static void
+test_nmp_genl_family_type_from_name(void)
+{
+    int n_run;
+    int i;
+
+    for (i = 0; i < (int) _NMP_GENL_FAMILY_TYPE_NUM; i++) {
+        const char *name = nmp_genl_family_infos[i].name;
+
+        g_assert(name);
+        if (i > 0)
+            g_assert_cmpint(strcmp(nmp_genl_family_infos[i - 1].name, name), <, 0);
+    }
+
+    g_assert_cmpint(nmp_genl_family_type_from_name("ethtool"), ==, NMP_GENL_FAMILY_TYPE_ETHTOOL);
+    g_assert_cmpint(nmp_genl_family_type_from_name("mptcp_pm"), ==, NMP_GENL_FAMILY_TYPE_MPTCP_PM);
+    g_assert_cmpint(nmp_genl_family_type_from_name("nl80211"), ==, NMP_GENL_FAMILY_TYPE_NL80211);
+    g_assert_cmpint(nmp_genl_family_type_from_name("nl802154"), ==, NMP_GENL_FAMILY_TYPE_NL802154);
+    g_assert_cmpint(nmp_genl_family_type_from_name("wireguard"),
+                    ==,
+                    NMP_GENL_FAMILY_TYPE_WIREGUARD);
+
+    g_assert_cmpint(nmp_genl_family_type_from_name(NULL), ==, _NMP_GENL_FAMILY_TYPE_NONE);
+    g_assert_cmpint(nmp_genl_family_type_from_name("a"), ==, _NMP_GENL_FAMILY_TYPE_NONE);
+    g_assert_cmpint(nmp_genl_family_type_from_name("wireguara"), ==, _NMP_GENL_FAMILY_TYPE_NONE);
+    g_assert_cmpint(nmp_genl_family_type_from_name("wireguarb"), ==, _NMP_GENL_FAMILY_TYPE_NONE);
+    g_assert_cmpint(nmp_genl_family_type_from_name(""), ==, _NMP_GENL_FAMILY_TYPE_NONE);
+    g_assert_cmpint(nmp_genl_family_type_from_name("z"), ==, _NMP_GENL_FAMILY_TYPE_NONE);
+
+    for (n_run = 0; n_run < 20; n_run++) {
+        for (i = 0; i < (int) _NMP_GENL_FAMILY_TYPE_NUM; i++) {
+            const char *cname  = nmp_genl_family_infos[i].name;
+            const int   ch_idx = nmtst_get_rand_uint() % strlen(cname);
+            char        name[200];
+            char        ch;
+            gsize       l;
+
+            l = g_strlcpy(name, cname, sizeof(name));
+            g_assert_cmpint(l, <, sizeof(name));
+
+            if (n_run == 0) {
+                g_assert_cmpint(nmp_genl_family_type_from_name(cname), ==, i);
+                g_assert_cmpint(nmp_genl_family_type_from_name(name), ==, i);
+            }
+
+            /* randomly change one character in the name. Such a name becomes invalid.
+             * There are no two valid names which only differ by one characters. */
+            do {
+                ch = nmtst_get_rand_uint() % 256;
+            } while (cname[ch_idx] == ch);
+            name[ch_idx] = ch;
+            g_assert_cmpint(nmp_genl_family_type_from_name(name), ==, _NMP_GENL_FAMILY_TYPE_NONE);
+        }
+    }
+}
+
+/*****************************************************************************/
+
 NMTST_DEFINE();
 
 int
@@ -808,6 +866,8 @@ main(int argc, char **argv)
                          GINT_TO_POINTER(2),
                          test_platform_ip_address_pretty_sort_cmp);
     g_test_add_func("/general/test_route_type_is_nodev", test_route_type_is_nodev);
+    g_test_add_func("/nm-platform/test_nmp_genl_family_type_from_name",
+                    test_nmp_genl_family_type_from_name);
 
     return g_test_run();
 }
diff --git a/src/libnm-platform/nm-platform.c b/src/libnm-platform/nm-platform.c
index 50204abc5f..ab21f3f289 100644
--- a/src/libnm-platform/nm-platform.c
+++ b/src/libnm-platform/nm-platform.c
@@ -395,6 +395,76 @@ _nm_platform_kernel_support_init(NMPlatformKernelSupportType type, int value)
 
 /*****************************************************************************/
 
+const NMPGenlFamilyInfo nmp_genl_family_infos[_NMP_GENL_FAMILY_TYPE_NUM] = {
+    [NMP_GENL_FAMILY_TYPE_ETHTOOL] =
+        {
+            .name = "ethtool",
+        },
+    [NMP_GENL_FAMILY_TYPE_MPTCP_PM] =
+        {
+            .name = "mptcp_pm",
+        },
+    [NMP_GENL_FAMILY_TYPE_NL80211] =
+        {
+            .name = "nl80211",
+        },
+    [NMP_GENL_FAMILY_TYPE_NL802154] =
+        {
+            .name = "nl802154",
+        },
+    [NMP_GENL_FAMILY_TYPE_WIREGUARD] =
+        {
+            .name = "wireguard",
+        },
+};
+
+NMPGenlFamilyType
+nmp_genl_family_type_from_name(const char *name)
+{
+    int imin, imax, imid;
+
+    if (NM_MORE_ASSERT_ONCE(50)) {
+        int i;
+
+        for (i = 0; i < (int) G_N_ELEMENTS(nmp_genl_family_infos); i++) {
+            nm_assert(nmp_genl_family_infos[i].name);
+            if (i > 0)
+                nm_assert(strcmp(nmp_genl_family_infos[i - 1].name, nmp_genl_family_infos[i].name)
+                          < 0);
+        }
+    }
+
+    if (!name)
+        goto out;
+
+    imin = 0;
+    imax = G_N_ELEMENTS(nmp_genl_family_infos) - 1;
+    imid = imax / 2;
+
+    while (TRUE) {
+        int c;
+
+        c = strcmp(nmp_genl_family_infos[imid].name, name);
+        if (c == 0)
+            return (NMPGenlFamilyType) imid;
+
+        if (c < 0)
+            imin = imid + 1;
+        else
+            imax = imid - 1;
+
+        if (imin > imax)
+            break;
+
+        imid = (imax + imin) / 2;
+    }
+
+out:
+    return _NMP_GENL_FAMILY_TYPE_NONE;
+}
+
+/*****************************************************************************/
+
 /**
  * nm_platform_process_events:
  * @self: platform instance
diff --git a/src/libnm-platform/nm-platform.h b/src/libnm-platform/nm-platform.h
index b921a2f562..e940f43b60 100644
--- a/src/libnm-platform/nm-platform.h
+++ b/src/libnm-platform/nm-platform.h
@@ -1103,6 +1103,25 @@ nm_platform_kernel_support_get(NMPlatformKernelSupportType type)
     return nm_platform_kernel_support_get_full(type, TRUE) != NM_OPTION_BOOL_FALSE;
 }
 
+typedef enum {
+    NMP_GENL_FAMILY_TYPE_ETHTOOL,
+    NMP_GENL_FAMILY_TYPE_MPTCP_PM,
+    NMP_GENL_FAMILY_TYPE_NL80211,
+    NMP_GENL_FAMILY_TYPE_NL802154,
+    NMP_GENL_FAMILY_TYPE_WIREGUARD,
+
+    _NMP_GENL_FAMILY_TYPE_NUM,
+    _NMP_GENL_FAMILY_TYPE_NONE = _NMP_GENL_FAMILY_TYPE_NUM,
+} NMPGenlFamilyType;
+
+typedef struct {
+    const char *name;
+} NMPGenlFamilyInfo;
+
+extern const NMPGenlFamilyInfo nmp_genl_family_infos[_NMP_GENL_FAMILY_TYPE_NUM];
+
+NMPGenlFamilyType nmp_genl_family_type_from_name(const char *name);
+
 /*****************************************************************************/
 
 struct _NMPlatformPrivate;