MEDIUM: checks: capture groups in expect regexes
Parse back-references in comments of tcp-check expect rules. If references are
made, capture groups in the match and replace references to it within the
comment when logging the error. Both text and binary regex can caputre groups
and reference them in the expect rule comment.
[Cf: I slightly updated the patch. exp_replace() function is used instead of a
custom one. And if the trash buffer is too small to contain the comment during
the substitution, the comment is ignored.]
diff --git a/src/checks.c b/src/checks.c
index a3e72ee..b2fb34d 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -3187,13 +3187,21 @@
match = my_memmem(b_head(&check->bi), b_data(&check->bi), expect->string, expect->length) != NULL;
break;
case TCPCHK_EXPECT_REGEX:
- match = regex_exec2(expect->regex, b_head(&check->bi), MIN(b_data(&check->bi), b_size(&check->bi)-1));
+ if (expect->with_capture)
+ match = regex_exec_match2(expect->regex, b_head(&check->bi), MIN(b_data(&check->bi), b_size(&check->bi)-1),
+ MAX_MATCH, pmatch, 0);
+ else
+ match = regex_exec2(expect->regex, b_head(&check->bi), MIN(b_data(&check->bi), b_size(&check->bi)-1));
break;
case TCPCHK_EXPECT_REGEX_BINARY:
chunk_reset(&trash);
dump_binary(&trash, b_head(&check->bi), b_data(&check->bi));
- match = regex_exec2(expect->regex, b_head(&trash), MIN(b_data(&trash), b_size(&trash)-1));
+ if (expect->with_capture)
+ match = regex_exec_match2(expect->regex, b_head(&trash), MIN(b_data(&trash), b_size(&trash)-1),
+ MAX_MATCH, pmatch, 0);
+ else
+ match = regex_exec2(expect->regex, b_head(&trash), MIN(b_data(&trash), b_size(&trash)-1));
break;
case TCPCHK_EXPECT_UNDEF:
/* Should never happen. */
@@ -3248,6 +3256,19 @@
case TCPCHK_EXPECT_REGEX_BINARY:
chunk_printf(&trash, "TCPCHK %s (binary regex) at step %d",
diag, step);
+
+ /* If references to the matched text were made,
+ * divide the offsets by 2 to match offset of
+ * the original response buffer.
+ */
+ if (expect->with_capture) {
+ int i;
+
+ for (i = 1; i < MAX_MATCH && pmatch[i].rm_so != -1; i++) {
+ pmatch[i].rm_so /= 2; /* at first matched char. */
+ pmatch[i].rm_eo /= 2; /* at last matched char. */
+ }
+ }
break;
case TCPCHK_EXPECT_UNDEF:
/* Should never happen. */
@@ -3256,11 +3277,16 @@
}
comment = tcpcheck_get_step_comment(check);
- if (comment)
- chunk_appendf(&trash, " comment: '%s'", comment);
- set_server_check_status(check, HCHK_STATUS_L7RSP,
- trash.area);
-
+ if (comment) {
+ if (expect->with_capture) {
+ ret = exp_replace(b_tail(&trash), b_room(&trash), b_head(&check->bi), comment, pmatch);
+ if (ret > 0) /* ignore comment if too large */
+ trash.data += ret;
+ }
+ else
+ chunk_appendf(&trash, " comment: '%s'", comment);
+ }
+ set_server_check_status(check, HCHK_STATUS_L7RSP, trash.area);
goto out_end_tcpcheck;
} /* end expect */
} /* end loop over double chained step list */