MINOR: sample: Add be2hex converter

Add be2hex converter to convert big-endian binary data into hex string
with optional string separators.

3 files changed, 135 insertions, 0 deletions

diff --git a/doc/configuration.txt b/doc/configuration.txt
index cbc967a7c..9c1e2b229 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -16105,6 +16105,20 @@ be2dec(<separator>,<chunk_size>,[<truncate>])
       bin(01020304050607),be2dec(,2,1)  # 2587721286
       bin(7f000001),be2dec(.,1)         # 127.0.0.1
 
+be2hex([<separator>],[<chunk_size>],[<truncate>])
+  Converts big-endian binary input sample to a hex string containing two hex
+  digits per input byte. It is used to log or transfer hex dumps of some
+  binary input data in a way that can be reliably transferred (e.g. an SSL ID
+  can be copied in a header). <separator> is put every <chunk_size> binary
+  input bytes if specified. <truncate> flag indicates whatever binary input is
+  truncated at <chunk_size> boundaries.
+
+  Example:
+      bin(01020304050607),be2hex         # 01020304050607
+      bin(01020304050607),be2hex(:,2)    # 0102:0304:0506:07
+      bin(01020304050607),be2hex(--,2,1) # 0102--0304--0506
+      bin(0102030405060708),be2hex(,3,1) # 010203040506
+
 bool
   Returns a boolean TRUE if the input value of type signed integer is
   non-null, otherwise returns FALSE. Used in conjunction with and(), it can be
diff --git a/reg-tests/converter/be2hex.vtc b/reg-tests/converter/be2hex.vtc
new file mode 100644
index 000000000..86e504292
--- /dev/null
+++ b/reg-tests/converter/be2hex.vtc
@@ -0,0 +1,60 @@
+varnishtest "be2hex converter Test"
+
+feature cmd "$HAPROXY_PROGRAM -cc 'version_atleast(2.5-dev0)'"
+feature ignore_unknown_macro
+
+server s1 {
+	rxreq
+	txresp
+} -repeat 3 -start
+
+haproxy h1 -conf {
+    defaults
+	mode http
+	timeout connect 1s
+	timeout client  1s
+	timeout server  1s
+
+    frontend fe
+	bind "fd@${fe}"
+
+	#### requests
+	http-request  set-var(txn.input) req.hdr(input)
+
+	http-response set-header be2hex     "%[var(txn.input),be2hex,lower]"
+	http-response set-header be2hex-1   "%[var(txn.input),be2hex(:,1),lower]"
+	http-response set-header be2hex-2   "%[var(txn.input),be2hex(--,3),lower]"
+	http-response set-header be2hex-3   "%[var(txn.input),be2hex(.,3,1),lower]"
+
+	default_backend be
+
+    backend be
+	server s1 ${s1_addr}:${s1_port}
+} -start
+
+client c1 -connect ${h1_fe_sock} {
+	txreq -url "/" \
+	  -hdr "input:"
+	rxresp
+	expect resp.status == 200
+	expect resp.http.be2hex   == ""
+	expect resp.http.be2hex-1 == ""
+	expect resp.http.be2hex-2 == ""
+	expect resp.http.be2hex-3 == ""
+	txreq -url "/" \
+	  -hdr "input: 0123456789"
+	rxresp
+	expect resp.status == 200
+	expect resp.http.be2hex   == "30313233343536373839"
+	expect resp.http.be2hex-1 == "30:31:32:33:34:35:36:37:38:39"
+	expect resp.http.be2hex-2 == "303132--333435--363738--39"
+	expect resp.http.be2hex-3 == "303132.333435.363738"
+	txreq -url "/" \
+	  -hdr "input: abcdefghijklmnopqrstuvwxyz"
+	rxresp
+	expect resp.status == 200
+	expect resp.http.be2hex   == "6162636465666768696a6b6c6d6e6f707172737475767778797a"
+	expect resp.http.be2hex-1 == "61:62:63:64:65:66:67:68:69:6a:6b:6c:6d:6e:6f:70:71:72:73:74:75:76:77:78:79:7a"
+	expect resp.http.be2hex-2 == "616263--646566--676869--6a6b6c--6d6e6f--707172--737475--767778--797a"
+	expect resp.http.be2hex-3 == "616263.646566.676869.6a6b6c.6d6e6f.707172.737475.767778"
+} -run
diff --git a/src/sample.c b/src/sample.c
index b354fc7bb..6f0ddee20 100644
--- a/src/sample.c
+++ b/src/sample.c
@@ -2123,6 +2123,66 @@ static int sample_conv_be2dec(const struct arg *args, struct sample *smp, void *
 	return 1;
 }
 
+static int sample_conv_be2hex_check(struct arg *args, struct sample_conv *conv,
+                                    const char *file, int line, char **err)
+{
+	if (args[1].data.sint <= 0 && (args[0].data.str.data > 0 || args[2].data.sint != 0)) {
+		memprintf(err, "chunk_size needs to be positive (%lld)", args[1].data.sint);
+		return 0;
+	}
+
+	if (args[2].data.sint != 0 && args[2].data.sint != 1) {
+		memprintf(err, "Unsupported truncate value (%lld)", args[2].data.sint);
+		return 0;
+	}
+
+	return 1;
+}
+
+/* Converts big-endian binary input sample to a hex string containing two hex
+ * digits per input byte. <separator> is put every <chunk_size> binary input
+ * bytes if specified. Optional <truncate> flag indicates if input is truncated
+ * at <chunk_size> boundaries.
+ * Arguments: separator (string), chunk_size (integer), truncate (0,1)
+ */
+static int sample_conv_be2hex(const struct arg *args, struct sample *smp, void *private)
+{
+	struct buffer *trash = get_trash_chunk();
+	int chunk_size = args[1].data.sint;
+	const int last = args[2].data.sint ? smp->data.u.str.data - chunk_size + 1 : smp->data.u.str.data;
+	int i;
+	int max_size;
+	int ptr = 0;
+	unsigned char c;
+
+	trash->data = 0;
+	if (args[0].data.str.data == 0 && args[2].data.sint == 0)
+		chunk_size = smp->data.u.str.data;
+	max_size = trash->size - 2 * chunk_size;
+
+	while (ptr < last && trash->data <= max_size) {
+		if (ptr) {
+			/* Add separator */
+			memcpy(trash->area + trash->data, args[0].data.str.area, args[0].data.str.data);
+			trash->data += args[0].data.str.data;
+		}
+		else
+			max_size -= args[0].data.str.data;
+
+		/* Add hex */
+		for (i = 0; i < chunk_size && ptr < smp->data.u.str.data; i++) {
+			c = smp->data.u.str.area[ptr++];
+			trash->area[trash->data++] = hextab[(c >> 4) & 0xF];
+			trash->area[trash->data++] = hextab[c & 0xF];
+		}
+	}
+
+	smp->data.u.str = *trash;
+	smp->data.type = SMP_T_STR;
+	smp->flags &= ~SMP_F_CONST;
+	return 1;
+}
+
 static int sample_conv_bin2hex(const struct arg *arg_p, struct sample *smp, void *private)
 {
 	struct buffer *trash = get_trash_chunk();
@@ -4318,6 +4378,7 @@ static struct sample_conv_kw_list sample_conv_kws = {ILH, {
 	{ "lower",   sample_conv_str2lower,    0,                     NULL,                     SMP_T_STR,  SMP_T_STR  },
 	{ "length",  sample_conv_length,       0,                     NULL,                     SMP_T_STR,  SMP_T_SINT },
 	{ "be2dec",  sample_conv_be2dec,       ARG3(1,STR,SINT,SINT), sample_conv_be2dec_check, SMP_T_BIN,  SMP_T_STR  },
+	{ "be2hex",  sample_conv_be2hex,       ARG3(1,STR,SINT,SINT), sample_conv_be2hex_check, SMP_T_BIN,  SMP_T_STR  },
 	{ "hex",     sample_conv_bin2hex,      0,                     NULL,                     SMP_T_BIN,  SMP_T_STR  },
 	{ "hex2i",   sample_conv_hex2int,      0,                     NULL,                     SMP_T_STR,  SMP_T_SINT },
 	{ "ipmask",  sample_conv_ipmask,       ARG2(1,MSK4,MSK6),     NULL,                     SMP_T_ADDR, SMP_T_IPV4 },