Hello,
I have added support for json to the version option but it would be nice
if you could take a look to it. I have followed the pattern of other
similar implementations. Thanks.
On 3/6/19 1:45 PM, Fernando Fernandez Mancera wrote:
> Signed-off-by: Fernando Fernandez Mancera <ffmancera@xxxxxxxxxx>
> ---
> doc/libnftables-json.adoc | 7 +++++-
> src/json.c | 13 +++++++++++
> src/parser_json.c | 48 ++++++++++++++++++++++++++++++++++++++-
> 3 files changed, 66 insertions(+), 2 deletions(-)
>
> diff --git a/doc/libnftables-json.adoc b/doc/libnftables-json.adoc
> index dbe5ac3..6981c69 100644
> --- a/doc/libnftables-json.adoc
> +++ b/doc/libnftables-json.adoc
> @@ -1302,11 +1302,16 @@ Construct a reference to packet's socket.
> ____
> *{ "osf": {
> "key":* 'OSF_KEY'*,
> - "ttl":* 'OSF_TTL'
> + "ttl":* 'OSF_TTL'*,
> + "flags":* 'OSF_FLAGS'
> *}}*
>
> 'OSF_KEY' := *"name"*
> 'OSF_TTL' := *"loose"* | *"skip"*
> +
> +'OSF_FLAGS' := 'OSF_FLAG' | *[* 'OSF_FLAG_LIST' *]*
> +'OSF_FLAG_LIST' := 'OSF_FLAG' [*,* 'OSF_FLAG_LIST' ]
> +'OSF_FLAG' := *"version"*
> ____
>
> Perform OS fingerprinting. This expression is typically used in the LHS of a *match*
> diff --git a/src/json.c b/src/json.c
> index 276a3c0..a46188d 100644
> --- a/src/json.c
> +++ b/src/json.c
> @@ -865,6 +865,7 @@ json_t *socket_expr_json(const struct expr *expr, struct output_ctx *octx)
> json_t *osf_expr_json(const struct expr *expr, struct output_ctx *octx)
> {
> json_t *root = json_pack("{s:s}", "key", "name");
> + const char *osf_flags[] = { "version" }
>
> switch (expr->osf.ttl) {
> case 1:
> @@ -875,6 +876,18 @@ json_t *osf_expr_json(const struct expr *expr, struct output_ctx *octx)
> break;
> }
>
> + if (expr->osf.flags) {
> + json_t *tmp = json_array();
> + unsigned int i;
> +
> + for (i = 0; i < array_size(osf_flags); i++) {
> + if (osf.flags & (1 << i)) {
> + json_array_append_new(tmp, json_string(osf_flags[i]));
> + }
> + }
> + json_object_set_new(root, "flags", tmp);
> + }
> +
> return json_pack("{s:o}", "osf", root);
> }
>
> diff --git a/src/parser_json.c b/src/parser_json.c
> index 7b190bc..ae197f0 100644
> --- a/src/parser_json.c
> +++ b/src/parser_json.c
> @@ -377,10 +377,26 @@ static struct expr *json_parse_meta_expr(struct json_ctx *ctx,
> return meta_expr_alloc(int_loc, key);
> }
>
> +static int osf_flag_parse(const char *name, int *flagval)
> +{
> + const char *osf_flags[] = { "version" };
> + unsigned int i;
> +
> + for (i = 0; i < array_size(osf_flags); i++) {
> + if (!strcmp(name, osf_flags[i])) {
> + *flagval |= (1 << i);
> + return 0;
> + }
> + }
> + return 1;
> +}
> +
> static struct expr *json_parse_osf_expr(struct json_ctx *ctx,
> const char *type, json_t *root)
> {
> + json_t *flags, *value;
> const char *key, *ttl;
> + uint8_t flagval = 0;
> uint8_t ttlval = 0;
>
> if (json_unpack_err(ctx, root, "{s:s}", "key", &key))
> @@ -397,8 +413,38 @@ static struct expr *json_parse_osf_expr(struct json_ctx *ctx,
> }
> }
>
> + if (!json_unpack(root, "{s:o}", "flags", &flags)) {
> + const char *flag;
> +
> + if (json_is_string(flags)) {
> + flag = json_string_value(flags);
> +
> + if (osf_flag_parse(flag, &flagval)) {
> + json_error(ctx, "Invalidad osf flag '%s'.", flag);
> + return NULL;
> + }
> +
> + } else if (!json_is_array) {
> + json_error(ctx, "Unexpected object type in osf flags tuple.");
> + return NULL;
> + }
> +
> + json_array_foreach(flags, index, value) {
> + if (!json_is_string(value)) {
> + json_error(ctx, "Unexpected object type in osf flags array at index %zd.", index);
> + return NULL;
> + }
> + flag = json_string_value(value);
> +
> + if (osf_flag_parse(flag, &flagval)) {
> + json_error(ctx, "Invalid osf flag '%s'.", flag);
> + return NULL;
> + }
> + }
> + }
> +
> if (!strcmp(key, "name"))
> - return osf_expr_alloc(int_loc, ttlval);
> + return osf_expr_alloc(int_loc, ttlval, flagval);
>
> json_error(ctx, "Invalid osf key value.");
> return NULL;
>
