MINOR: payload: allow the payload sample fetches to retrieve arbitrary lengths

When using req.payload and res.payload to look up for specific content at an
arbitrary location, we're often facing the problem of not knowing the input
buffer length. If the length argument is larger than the buffer length, the
function did not match, and if they're smaller, there is a risk of not getting
the expected content. This is especially true when looking for data in SOAP
requests.

So let's make some provisions for scanning the whole buffer by specifying a
length of 0 bytes. This greatly simplifies the processing of random-sized
input data.

diff --git a/doc/configuration.txt b/doc/configuration.txt
index c683387d0242bc7552443ee5a8d3fbd78a1af21f..87de59517e15bfff029a0a2f250d9a6b1323cbe1 100644 (file)
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -9662,7 +9662,10 @@ req_len : integer (deprecated)
 
 req.payload(<offset>,<length>) : binary
   This extracts a binary block of <length> bytes and starting at byte <offset>
-  in the request buffer.
+  in the request buffer. As a special case, if the <length> argument is zero,
+  the the whole buffer from <offset> to the end is extracted. This can be used
+  with ACLs in order to check for the presence of some content in a buffer at
+  any location.
 
   ACL alternatives :
     payload(<offset>,<length>) : hex binary match
@@ -9805,7 +9808,10 @@ req_ssl_ver : integer (deprecated)
 
 res.payload(<offset>,<length>) : binary
   This extracts a binary block of <length> bytes and starting at byte <offset>
-  in the response buffer.
+  in the response buffer. As a special case, if the <length> argument is zero,
+  the the whole buffer from <offset> to the end is extracted. This can be used
+  with ACLs in order to check for the presence of some content in a buffer at
+  any location.
 
 res.payload_lv(<offset1>,<length>[,<offset2>]) : binary
   This extracts a binary block whose size is specified at <offset1> for <length>

diff --git a/src/payload.c b/src/payload.c
index 05418aca6f360fd6cad1088f90a23289e9df5646..227379b0d484b359a15230181b29a0af82202bff 100644 (file)
--- a/src/payload.c
+++ b/src/payload.c
@@ -589,7 +589,7 @@ smp_fetch_payload(struct proxy *px, struct session *s, void *l7, unsigned int op
        if (!chn)
                return 0;
 
-       if (!buf_size || buf_size > chn->buf->size || buf_offset + buf_size > chn->buf->size) {
+       if (buf_size > chn->buf->size || buf_offset + buf_size > chn->buf->size) {
                /* will never match */
                smp->flags = 0;
                return 0;
@@ -600,8 +600,11 @@ smp_fetch_payload(struct proxy *px, struct session *s, void *l7, unsigned int op
 
        /* init chunk as read only */
        smp->type = SMP_T_CBIN;
-       chunk_initlen(&smp->data.str, chn->buf->p + buf_offset, 0, buf_size);
+       chunk_initlen(&smp->data.str, chn->buf->p + buf_offset, 0, buf_size ? buf_size : (chn->buf->i - buf_offset));
        smp->flags = SMP_F_VOLATILE;
+       if (!buf_size && !channel_full(chn) && !channel_input_closed(chn))
+               smp->flags |= SMP_F_MAY_CHANGE;
+
        return 1;
 
  too_short:
@@ -609,23 +612,6 @@ smp_fetch_payload(struct proxy *px, struct session *s, void *l7, unsigned int op
        return 0;
 }
 
-/* This function is used to validate the arguments passed to a "payload" fetch
- * keyword. This keyword expects two positive integers, with the second one
- * being strictly positive. It is assumed that the types are already the correct
- * ones. Returns 0 on error, non-zero if OK. If <err_msg> is not NULL, it will be
- * filled with a pointer to an error message in case of error, that the caller
- * is responsible for freeing. The initial location must either be freeable or
- * NULL.
- */
-static int val_payload(struct arg *arg, char **err_msg)
-{
-       if (!arg[1].data.uint) {
-               memprintf(err_msg, "payload length must be > 0");
-               return 0;
-       }
-       return 1;
-}
-
 /* This function is used to validate the arguments passed to a "payload_lv" fetch
  * keyword. This keyword allows two positive integers and an optional signed one,
  * with the second one being strictly positive and the third one being greater than
@@ -660,7 +646,7 @@ static int val_payload_lv(struct arg *arg, char **err_msg)
  * instance IPv4/IPv6 must be declared IPv4.
  */
 static struct sample_fetch_kw_list smp_kws = {ILH, {
-       { "payload",             smp_fetch_payload,        ARG2(2,UINT,UINT),      val_payload,    SMP_T_CBIN, SMP_USE_L6REQ|SMP_USE_L6RES },
+       { "payload",             smp_fetch_payload,        ARG2(2,UINT,UINT),      NULL,           SMP_T_CBIN, SMP_USE_L6REQ|SMP_USE_L6RES },
        { "payload_lv",          smp_fetch_payload_lv,     ARG3(2,UINT,UINT,SINT), val_payload_lv, SMP_T_CBIN, SMP_USE_L6REQ|SMP_USE_L6RES },
        { "rdp_cookie",          smp_fetch_rdp_cookie,     ARG1(0,STR),            NULL,           SMP_T_CSTR, SMP_USE_L6REQ },
        { "rdp_cookie_cnt",      smp_fetch_rdp_cookie_cnt, ARG1(0,STR),            NULL,           SMP_T_UINT, SMP_USE_L6REQ },
@@ -671,14 +657,14 @@ static struct sample_fetch_kw_list smp_kws = {ILH, {
        { "req_ssl_ver",         smp_fetch_req_ssl_ver,    0,                      NULL,           SMP_T_UINT, SMP_USE_L6REQ },
 
        { "req.len",             smp_fetch_req_len,        0,                      NULL,           SMP_T_UINT, SMP_USE_L6REQ },
-       { "req.payload",         smp_fetch_payload,        ARG2(2,UINT,UINT),      val_payload,    SMP_T_CBIN, SMP_USE_L6REQ },
+       { "req.payload",         smp_fetch_payload,        ARG2(2,UINT,UINT),      NULL,           SMP_T_CBIN, SMP_USE_L6REQ },
        { "req.payload_lv",      smp_fetch_payload_lv,     ARG3(2,UINT,UINT,SINT), val_payload_lv, SMP_T_CBIN, SMP_USE_L6REQ },
        { "req.rdp_cookie",      smp_fetch_rdp_cookie,     ARG1(0,STR),            NULL,           SMP_T_CSTR, SMP_USE_L6REQ },
        { "req.rdp_cookie_cnt",  smp_fetch_rdp_cookie_cnt, ARG1(0,STR),            NULL,           SMP_T_UINT, SMP_USE_L6REQ },
        { "req.ssl_hello_type",  smp_fetch_ssl_hello_type, 0,                      NULL,           SMP_T_UINT, SMP_USE_L6REQ },
        { "req.ssl_sni",         smp_fetch_ssl_hello_sni,  0,                      NULL,           SMP_T_CSTR, SMP_USE_L6REQ },
        { "req.ssl_ver",         smp_fetch_req_ssl_ver,    0,                      NULL,           SMP_T_UINT, SMP_USE_L6REQ },
-       { "res.payload",         smp_fetch_payload,        ARG2(2,UINT,UINT),      val_payload,    SMP_T_CBIN, SMP_USE_L6RES },
+       { "res.payload",         smp_fetch_payload,        ARG2(2,UINT,UINT),      NULL,           SMP_T_CBIN, SMP_USE_L6RES },
        { "res.payload_lv",      smp_fetch_payload_lv,     ARG3(2,UINT,UINT,SINT), val_payload_lv, SMP_T_CBIN, SMP_USE_L6RES },
        { "res.ssl_hello_type",  smp_fetch_ssl_hello_type, 0,                      NULL,           SMP_T_UINT, SMP_USE_L6RES },
        { "wait_end",            smp_fetch_wait_end,       0,                      NULL,           SMP_T_BOOL, SMP_USE_INTRN },