MINOR: http_ext: add rfc7239_n2np converter
Adding new http converter: rfc7239_n2np.
Takes a string representing 7239 forwarded header node (extracted from
either 'for' or 'by' 7239 header fields) as input and translates it
to either unsigned integer or ('_' prefixed obfuscated identifier),
according to 7239RFC.
Example:
# extract 'by' field from forwarded header, extract node port from
# resulting node identifier and store the result in req.fnp
http-request set-var(req.fnp) req.hdr(forwarded),rfc7239_field(by),rfc7239_n2np
#input: "by=\"127.0.0.1:9999\""
# output: 9999
#input: "by=\"_name:_port\""
# output: "_port"
Depends on:
- "MINOR: http_ext: introduce http ext converters"
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 37c2d33..b01b30a 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -17268,6 +17268,21 @@
#input: "for=\"_name:_port\""
# output: "_name"
+rfc7239_n2np
+ Converts RFC7239 node (provided by 'for' or 'by' 7239 header fields)
+ into its corresponding nodeport final form:
+ - unsigned integer
+ - '_obfs' identifier
+
+ Example:
+ # extract 'by' field from forwarded header, extract node port from
+ # resulting node identifier and store the result in req.fnp
+ http-request set-var(req.fnp) req.hdr(forwarded),rfc7239_field(by),rfc7239_n2np
+ #input: "by=\"127.0.0.1:9999\""
+ # output: 9999
+ #input: "by=\"_name:_port\""
+ # output: "_port"
+
add(<value>)
Adds <value> to the input value of type signed integer, and returns the
result as a signed integer. <value> can be a numeric value or a variable
diff --git a/src/http_ext.c b/src/http_ext.c
index 3681bd0..62aa55d 100644
--- a/src/http_ext.c
+++ b/src/http_ext.c
@@ -1480,11 +1480,47 @@
return 1;
}
+/* input: substring representing 7239 forwarded header node
+ * output: forwarded header nodeport translated to either
+ * integer or str for obfuscated ('_' prefix)
+ */
+static int sample_conv_7239_n2np(const struct arg *args, struct sample *smp, void *private)
+{
+ struct ist input = ist2(smp->data.u.str.area, smp->data.u.str.data);
+ struct forwarded_header_node ctx;
+ struct buffer *output;
+
+ if (http_7239_extract_node(&input, &ctx, 1) == 0)
+ return 0; /* could not extract node */
+
+ switch (ctx.nodeport.type) {
+ case FORWARDED_HEADER_UNK:
+ return 0; /* not provided */
+ case FORWARDED_HEADER_OBFS:
+ output = get_trash_chunk();
+ chunk_appendf(output, "_"); /* append obfs prefix */
+ chunk_istcat(output, ctx.nodeport.obfs);
+ smp->flags &= ~SMP_F_CONST;
+ smp->data.type = SMP_T_STR;
+ smp->data.u.str = *output;
+ break;
+ case FORWARDED_HEADER_PORT:
+ smp->data.type = SMP_T_SINT;
+ smp->data.u.sint = ctx.nodeport.port;
+ break;
+ default:
+ return 0; /* unsupported */
+ }
+
+ return 1;
+}
+
/* Note: must not be declared <const> as its list will be overwritten */
static struct sample_conv_kw_list sample_conv_kws = {ILH, {
{ "rfc7239_is_valid", sample_conv_7239_valid, 0, NULL, SMP_T_STR, SMP_T_BOOL},
{ "rfc7239_field", sample_conv_7239_field, ARG1(1,STR), NULL, SMP_T_STR, SMP_T_STR},
{ "rfc7239_n2nn", sample_conv_7239_n2nn, 0, NULL, SMP_T_STR, SMP_T_ANY},
+ { "rfc7239_n2np", sample_conv_7239_n2np, 0, NULL, SMP_T_STR, SMP_T_ANY},
{ NULL, NULL, 0, 0, 0 },
}};