On Thursday, 13 May 2021 16:02:34 CEST Alexander Sarmanow wrote:
> To print JSON strings in a generic way a second nla_policy is used, with
This is not a nla_policy but a private json translation "policy".
[...]
> new file mode 100644
> index 0000000..cff54d8
> --- /dev/null
> +++ b/genl_json.c
> @@ -0,0 +1,359 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright (C) B.A.T.M.A.N. contributors:
> + *
> + * Alexander Sarmanow <asarmanow@gmail.com>
> + *
> + * License-Filename: LICENSES/preferred/GPL-2.0
> + */
> +
> +#include <stdbool.h>
> +#include <stdio.h>
> +#include <ctype.h>
> +#include <netlink/netlink.h>
> +#include <netlink/attr.h>
> +
> +#include "genl_json.h"
> +#include "batman_adv.h"
> +#include "netlink.h"
> +#include "main.h"
#include "genl_json.h"
#include "main.h"
#include <ctype.h>
#include <inttypes.h>
#include <netlink/netlink.h>
#include <netlink/attr.h>
#include <stdbool.h>
#include <stdio.h>
#include "batman_adv.h"
#include "netlink.h"
> +static void nljson_print_uint8_t(struct nlattr *attrs[], int idx)
> +{
> + uint8_t value = nla_get_u8(attrs[idx]);
> +
> + printf("%u", value);
> +}
"%"PRIu8
> +
> +static void nljson_print_uint16_t(struct nlattr *attrs[], int idx)
> +{
> + uint16_t value = nla_get_u16(attrs[idx]);
> +
> + printf("%u", value);
> +}
"%"PRIu16
> +
> +static void nljson_print_uint32_t(struct nlattr *attrs[], int idx)
> +{
> + uint32_t value = nla_get_u32(attrs[idx]);
> +
> + printf("%u", value);
> +}
"%"PRIu32
> +
> +static void nljson_print_uint64_t(struct nlattr *attrs[], int idx)
> +{
> + uint64_t value = nla_get_u64(attrs[idx]);
> +
> + printf("%llu", value);
> +}
"%"PRIu64
> +
> +static void nljson_print_mac(struct nlattr *attrs[], int idx)
> +{
> + uint8_t *value = nla_data(attrs[idx]);
> +
> + printf("\"%02x:%02x:%02x:%02x:%02x:%02x\"",
> + value[0], value[1], value[2], value[3], value[4], value[5]);
> +}
Alignment
> +static void nljson_print_flag(struct nlattr *attrs[], int idx)
> +{
> + if (nla_get_flag(attrs[idx]))
> + printf("true");
> +}
The check is not necessary because it check only if attrs[idx] is != NULL -
which you've already checked. If this would not be the case, then this
function would create broken json like '{"foobar":}', right?
> +
> +void sanitize_string(const char *str)
> +{
> + while (*str) {
> + if (*str == '"' || *str == '\\') {
> + putchar('\\');
> + putchar(*str);
> + } else if (*str == '\\') {
> + printf("\\\\");
> + } else if (!isprint(*str)) {
> + printf("\\x%02x", *str);
> + } else {
> + printf("%c", *str);
> + }
if (*str == '"' || *str == '\\') {
putchar('\\');
putchar(*str);
} else if (!isprint(*str)) {
printf("\\x%02x", *str);
} else {
putchar(*str);
}
> + str++;
> + }
> +}
This function should have been static and at the beginning of this file.
> +
> +void netlink_print_json_entries(struct nlattr *attrs[], struct json_opts *json_opts)
> +{
> + bool first_valid_attr = true;
> + int i;
> +
> + if (!json_opts->is_first)
> + printf(",");
Code to handle the json_opts->is_first = false was again not added to this
function.
> +
> + printf("{");
> + for (i = 0; i < BATADV_ATTR_MAX + 1; i++) {
> + if (!attrs[i])
> + continue;
> +
> + if (!batadv_netlink_policy_json[i].cb)
> + continue;
> +
> + if (!first_valid_attr)
> + printf(",");
> +
> + putc('"', stdout);
> + sanitize_string(batadv_netlink_policy_json[i].name);
> + printf("\":");
> + batadv_netlink_policy_json[i].cb(attrs, i);
> +
> + first_valid_attr = false;
> + }
> + printf("}");
> +}
> +
> +
> +struct nla_policy_json batadv_netlink_policy_json[NUM_BATADV_ATTR] = {
this should have been static const
> + [BATADV_ATTR_PAD] = {
> + .name = "pad",
> + },
I would guess we can ignore this one.
> + [BATADV_ATTR_TT_FLAGS] = {
> + .name = "tt_flags",
> + .cb = nljson_print_uint32_t,
> + },
Why was the actually decoding removed?
> + [BATADV_ATTR_DAT_CACHE_IP4ADDRESS] = {
> + .name = "dat_cache_ip4_address",
> + },
IPv4 print code missing
[...]
> + [BATADV_ATTR_VLANID] = {
> + .name = "vlan_id",
> + .cb = nljson_print_uint16_t,
> + },
wasn't this originally printed in a special way?
> + [BATADV_ATTR_AGGREGATED_OGMS_ENABLED] = {
> + .name = "aggregated_ogms_enabled",
> + .cb = nljson_print_uint8_t,
> + },
This and other _ENABLED are booleans.
[...]
There were also different other weird names used. Like fragmented_enabled for
the fragmentation feature.
> diff --git a/genl_json.h b/genl_json.h
> new file mode 100644
> index 0000000..0336b40
> --- /dev/null
> +++ b/genl_json.h
> @@ -0,0 +1,24 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright (C) B.A.T.M.A.N. contributors:
> + *
> + * Alexander Sarmanow <asarmanow@gmail.com>
> + *
> + * License-Filename: LICENSES/preferred/GPL-2.0
> + */
> +
> +#ifndef _BATCTL_GENLJSON_H
> +#define _BATCTL_GENLJSON_H
> +
> +#include <stdint.h>
> +
> +#include "netlink.h"
> +
> +struct json_opts {
> + uint8_t is_first;
is_first:1
> + struct nlquery_opts query_opts;
> +};
> +
> +void netlink_print_json_entries(struct nlattr *attrs[], struct json_opts *json_opts);
> +void sanitize_string(const char *str);
> +
> +#endif /* _BATCTL_GENLJSON_H */
> diff --git a/netlink.h b/netlink.h
> index c93f500..d96935a 100644
> --- a/netlink.h
> +++ b/netlink.h
> @@ -29,6 +29,11 @@ struct nlquery_opts {
> int err;
> };
>
> +struct nla_policy_json {
> + const char *name;
> + void (*cb)(struct nlattr *attrs[], int idx);
> +};
> +
This doesn't belong to netlink.h. If it would really be needed outside of
genl_json.c then you should have added it to genl_json.h
> struct ether_addr;
>
> int netlink_create(struct state *state);
> @@ -44,6 +49,7 @@ int get_algoname_netlink(struct state *state, unsigned int mesh_ifindex,
> char *algoname, size_t algoname_len);
>
> extern struct nla_policy batadv_netlink_policy[];
> +extern struct nla_policy_json batadv_netlink_policy_json[];
This doesn't belong to netlink.h. If it would really be needed outside of
genl_json.c then you should have added it to genl_json.h
Kind regards,
Sven
@@ -16,6 +16,7 @@ obj-y += bat-hosts.o
obj-y += debug.o
obj-y += functions.o
obj-y += genl.o
+obj-y += genl_json.o
obj-y += hash.o
obj-y += icmp_helper.o
obj-y += main.o
new file mode 100644
@@ -0,0 +1,359 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) B.A.T.M.A.N. contributors:
+ *
+ * Alexander Sarmanow <asarmanow@gmail.com>
+ *
+ * License-Filename: LICENSES/preferred/GPL-2.0
+ */
+
+#include <stdbool.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <netlink/netlink.h>
+#include <netlink/attr.h>
+
+#include "genl_json.h"
+#include "batman_adv.h"
+#include "netlink.h"
+#include "main.h"
+
+static void nljson_print_str(struct nlattr *attrs[], int idx)
+{
+ const char *value;
+
+ value = nla_get_string(attrs[idx]);
+
+ putc('"', stdout);
+ sanitize_string(value);
+ putc('"', stdout);
+}
+
+static void nljson_print_uint8_t(struct nlattr *attrs[], int idx)
+{
+ uint8_t value = nla_get_u8(attrs[idx]);
+
+ printf("%u", value);
+}
+
+static void nljson_print_uint16_t(struct nlattr *attrs[], int idx)
+{
+ uint16_t value = nla_get_u16(attrs[idx]);
+
+ printf("%u", value);
+}
+
+static void nljson_print_uint32_t(struct nlattr *attrs[], int idx)
+{
+ uint32_t value = nla_get_u32(attrs[idx]);
+
+ printf("%u", value);
+}
+
+static void nljson_print_uint64_t(struct nlattr *attrs[], int idx)
+{
+ uint64_t value = nla_get_u64(attrs[idx]);
+
+ printf("%llu", value);
+}
+
+static void nljson_print_mac(struct nlattr *attrs[], int idx)
+{
+ uint8_t *value = nla_data(attrs[idx]);
+
+ printf("\"%02x:%02x:%02x:%02x:%02x:%02x\"",
+ value[0], value[1], value[2], value[3], value[4], value[5]);
+}
+
+static void nljson_print_flag(struct nlattr *attrs[], int idx)
+{
+ if (nla_get_flag(attrs[idx]))
+ printf("true");
+}
+
+void sanitize_string(const char *str)
+{
+ while (*str) {
+ if (*str == '"' || *str == '\\') {
+ putchar('\\');
+ putchar(*str);
+ } else if (*str == '\\') {
+ printf("\\\\");
+ } else if (!isprint(*str)) {
+ printf("\\x%02x", *str);
+ } else {
+ printf("%c", *str);
+ }
+ str++;
+ }
+}
+
+void netlink_print_json_entries(struct nlattr *attrs[], struct json_opts *json_opts)
+{
+ bool first_valid_attr = true;
+ int i;
+
+ if (!json_opts->is_first)
+ printf(",");
+
+ printf("{");
+ for (i = 0; i < BATADV_ATTR_MAX + 1; i++) {
+ if (!attrs[i])
+ continue;
+
+ if (!batadv_netlink_policy_json[i].cb)
+ continue;
+
+ if (!first_valid_attr)
+ printf(",");
+
+ putc('"', stdout);
+ sanitize_string(batadv_netlink_policy_json[i].name);
+ printf("\":");
+ batadv_netlink_policy_json[i].cb(attrs, i);
+
+ first_valid_attr = false;
+ }
+ printf("}");
+}
+
+
+struct nla_policy_json batadv_netlink_policy_json[NUM_BATADV_ATTR] = {
+ [BATADV_ATTR_VERSION] = {
+ .name = "version",
+ .cb = nljson_print_str,
+ },
+ [BATADV_ATTR_ALGO_NAME] = {
+ .name = "algo_name",
+ .cb = nljson_print_str,
+ },
+ [BATADV_ATTR_MESH_IFINDEX] = {
+ .name = "mesh_ifindex",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_MESH_IFNAME] = {
+ .name = "mesh_ifname",
+ .cb = nljson_print_str,
+ },
+ [BATADV_ATTR_MESH_ADDRESS] = {
+ .name = "mesh_address",
+ .cb = nljson_print_mac,
+ },
+ [BATADV_ATTR_HARD_IFINDEX] = {
+ .name = "hard_ifindex",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_HARD_IFNAME] = {
+ .name = "hard_ifname",
+ .cb = nljson_print_str,
+ },
+ [BATADV_ATTR_HARD_ADDRESS] = {
+ .name = "hard_address",
+ .cb = nljson_print_mac,
+ },
+ [BATADV_ATTR_ORIG_ADDRESS] = {
+ .name = "orig_address",
+ .cb = nljson_print_mac,
+ },
+ [BATADV_ATTR_TPMETER_RESULT] = {
+ .name = "tpmeter_result",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_TPMETER_TEST_TIME] = {
+ .name = "tpmeter_test_time",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_TPMETER_BYTES] = {
+ .name = "tpmeter_bytes",
+ .cb = nljson_print_uint64_t
+ },
+ [BATADV_ATTR_TPMETER_COOKIE] = {
+ .name = "tpmeter_cookie",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_PAD] = {
+ .name = "pad",
+ },
+ [BATADV_ATTR_ACTIVE] = {
+ .name = "active",
+ .cb = nljson_print_flag,
+ },
+ [BATADV_ATTR_TT_ADDRESS] = {
+ .name = "tt_address",
+ .cb = nljson_print_mac,
+ },
+ [BATADV_ATTR_TT_TTVN] = {
+ .name = "tt_ttvn",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_TT_LAST_TTVN] = {
+ .name = "last_ttvn",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_TT_CRC32] = {
+ .name = "crc32",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_TT_VID] = {
+ .name = "tt_vid",
+ .cb = nljson_print_uint16_t,
+ },
+ [BATADV_ATTR_TT_FLAGS] = {
+ .name = "tt_flags",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_FLAG_BEST] = {
+ .name = "best",
+ .cb = nljson_print_flag,
+ },
+ [BATADV_ATTR_LAST_SEEN_MSECS] = {
+ .name = "last_seen_msecs",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_NEIGH_ADDRESS] = {
+ .name = "neigh_address",
+ .cb = nljson_print_mac,
+ },
+ [BATADV_ATTR_TQ] = {
+ .name = "tq",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_THROUGHPUT] = {
+ .name = "throughput",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_BANDWIDTH_UP] = {
+ .name = "bandwidth_up",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_BANDWIDTH_DOWN] = {
+ .name = "bandwidth_down",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_ROUTER] = {
+ .name = "router",
+ .cb = nljson_print_mac,
+ },
+ [BATADV_ATTR_BLA_OWN] = {
+ .name = "bla_own",
+ .cb = nljson_print_flag,
+ },
+ [BATADV_ATTR_BLA_ADDRESS] = {
+ .name = "bla_address",
+ .cb = nljson_print_mac,
+ },
+ [BATADV_ATTR_BLA_VID] = {
+ .name = "bla_vid",
+ .cb = nljson_print_uint16_t,
+ },
+ [BATADV_ATTR_BLA_BACKBONE] = {
+ .name = "bla_backbone",
+ .cb = nljson_print_mac,
+ },
+ [BATADV_ATTR_BLA_CRC] = {
+ .name = "bla_crc",
+ .cb = nljson_print_uint16_t,
+ },
+ [BATADV_ATTR_DAT_CACHE_IP4ADDRESS] = {
+ .name = "dat_cache_ip4_address",
+ },
+ [BATADV_ATTR_DAT_CACHE_HWADDRESS] = {
+ .name = "dat_cache_hw_address",
+ .cb = nljson_print_mac,
+ },
+ [BATADV_ATTR_DAT_CACHE_VID] = {
+ .name = "dat_cache_vid",
+ .cb = nljson_print_uint16_t,
+ },
+ [BATADV_ATTR_MCAST_FLAGS] = {
+ .name = "mcast_flags",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_MCAST_FLAGS_PRIV] = {
+ .name = "mcast_flags_priv",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_VLANID] = {
+ .name = "vlan_id",
+ .cb = nljson_print_uint16_t,
+ },
+ [BATADV_ATTR_AGGREGATED_OGMS_ENABLED] = {
+ .name = "aggregated_ogms_enabled",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_AP_ISOLATION_ENABLED] = {
+ .name = "ap_isolation_enabled",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_ISOLATION_MARK] = {
+ .name = "isolation_mark",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_ISOLATION_MASK] = {
+ .name = "isolation_mask",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_BONDING_ENABLED] = {
+ .name = "bonding_enabled",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_BRIDGE_LOOP_AVOIDANCE_ENABLED] = {
+ .name = "bridge_loop_avoidance_enabled",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_DISTRIBUTED_ARP_TABLE_ENABLED] = {
+ .name = "distributed_arp_table_enabled",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_FRAGMENTATION_ENABLED] = {
+ .name = "fragmented_enabled",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_GW_BANDWIDTH_DOWN] = {
+ .name = "bandwidth_down",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_GW_BANDWIDTH_UP] = {
+ .name = "bandwidth_up",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_GW_MODE] = {
+ .name = "gw_mode",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_GW_SEL_CLASS] = {
+ .name = "gw_sel_class",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_HOP_PENALTY] = {
+ .name = "hop_penalty",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_LOG_LEVEL] = {
+ .name = "log_level",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_MULTICAST_FORCEFLOOD_ENABLED] = {
+ .name = "multicast_forceflood_enabled",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_NETWORK_CODING_ENABLED] = {
+ .name = "network_coding_enabled",
+ .cb = nljson_print_uint8_t,
+ },
+ [BATADV_ATTR_ORIG_INTERVAL] = {
+ .name = "orig_interval",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_ELP_INTERVAL] = {
+ .name = "elp_interval",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_THROUGHPUT_OVERRIDE] = {
+ .name = "throughput_override",
+ .cb = nljson_print_uint32_t,
+ },
+ [BATADV_ATTR_MULTICAST_FANOUT] = {
+ .name = "multicast_fanout",
+ .cb = nljson_print_uint32_t,
+ },
+};
new file mode 100644
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) B.A.T.M.A.N. contributors:
+ *
+ * Alexander Sarmanow <asarmanow@gmail.com>
+ *
+ * License-Filename: LICENSES/preferred/GPL-2.0
+ */
+
+#ifndef _BATCTL_GENLJSON_H
+#define _BATCTL_GENLJSON_H
+
+#include <stdint.h>
+
+#include "netlink.h"
+
+struct json_opts {
+ uint8_t is_first;
+ struct nlquery_opts query_opts;
+};
+
+void netlink_print_json_entries(struct nlattr *attrs[], struct json_opts *json_opts);
+void sanitize_string(const char *str);
+
+#endif /* _BATCTL_GENLJSON_H */
@@ -29,6 +29,11 @@ struct nlquery_opts {
int err;
};
+struct nla_policy_json {
+ const char *name;
+ void (*cb)(struct nlattr *attrs[], int idx);
+};
+
struct ether_addr;
int netlink_create(struct state *state);
@@ -44,6 +49,7 @@ int get_algoname_netlink(struct state *state, unsigned int mesh_ifindex,
char *algoname, size_t algoname_len);
extern struct nla_policy batadv_netlink_policy[];
+extern struct nla_policy_json batadv_netlink_policy_json[];
int missing_mandatory_attrs(struct nlattr *attrs[], const int mandatory[],
int num);