caddyhttp: Explicitly disallow multiple regexp matchers (#5030)

* caddyhttp: Explicitly disallow multiple regexp matchers Fix #5028 Since the matchers would overwrite eachother, we should error out to tell the user their config doesn't make sense. * Update modules/caddyhttp/matchers.go Co-authored-by: Matt Holt <mholt@users.noreply.github.com>

Francis Lavoie committed Sep 13, 2022 at 13:18 UTC 61c75f74dec6b0524feef9b24ef8d6005f096b09

1 file changed +13

modules/caddyhttp/matchers.go

+13

@@ -1001,6 +1001,12 @@ func (m *MatchHeaderRE) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {

1001 val = second

1002 }

1003

1004 + // If there's already a pattern for this field

1005 + // then we would end up overwriting the old one

1006 + if (*m)[field] != nil {

1007 + return d.Errf("header_regexp matcher can only be used once per named matcher, per header field: %s", field)

1008 + }

1009 +

1010 (*m)[field] = &MatchRegexp{Pattern: val, Name: name}

1011

1012 if d.NextBlock(0) {

@@ -1469,6 +1475,13 @@ func (mre *MatchRegexp) Match(input string, repl *caddy.Replacer) bool {

1475 // UnmarshalCaddyfile implements caddyfile.Unmarshaler.

1476 func (mre *MatchRegexp) UnmarshalCaddyfile(d *caddyfile.Dispenser) error {

1477 for d.Next() {

1478 + // If this is the second iteration of the loop

1479 + // then there's more than one path_regexp matcher

1480 + // and we would end up overwriting the old one

1481 + if mre.Pattern != "" {

1482 + return d.Err("regular expression can only be used once per named matcher")

1483 + }

1484 +

1485 args := d.RemainingArgs()

1486 switch len(args) {

1487 case 1: