diff --git a/command/agent/http.go b/command/agent/http.go index 6e33ad4af..66fed38df 100644 --- a/command/agent/http.go +++ b/command/agent/http.go @@ -40,6 +40,10 @@ const ( // MissingRequestID is a placeholder if we cannot retrieve a request // UUID from context MissingRequestID = "" + + // HTTPConnStateFuncWriteTimeout is how long to try to write conn state errors + // before closing the connection + HTTPConnStateFuncWriteTimeout = 10 * time.Millisecond ) var ( @@ -171,7 +175,7 @@ func makeConnState(isTLS bool, handshakeTimeout time.Duration, connLimit int) fu // Still return the connection limiter return connlimit.NewLimiter(connlimit.Config{ MaxConnsPerClientIP: connLimit, - }).HTTPConnStateFunc() + }).HTTPConnStateFuncWithDefault429Handler(HTTPConnStateFuncWriteTimeout) } return nil @@ -183,7 +187,7 @@ func makeConnState(isTLS bool, handshakeTimeout time.Duration, connLimit int) fu connLimiter := connlimit.NewLimiter(connlimit.Config{ MaxConnsPerClientIP: connLimit, - }).HTTPConnStateFunc() + }).HTTPConnStateFuncWithDefault429Handler(HTTPConnStateFuncWriteTimeout) return func(conn net.Conn, state http.ConnState) { switch state { diff --git a/command/agent/http_test.go b/command/agent/http_test.go index dddc8f82c..68f2ac868 100644 --- a/command/agent/http_test.go +++ b/command/agent/http_test.go @@ -14,6 +14,7 @@ import ( "net/http/httptest" "net/url" "os" + "strconv" "strings" "testing" "time" @@ -869,15 +870,24 @@ func TestHTTPServer_Limits_Error(t *testing.T) { } } +func limitStr(limit *int) string { + if limit == nil { + return "none" + } + return strconv.Itoa(*limit) +} + // TestHTTPServer_Limits_OK asserts that all valid limits combinations // (tls/timeout/conns) work. func TestHTTPServer_Limits_OK(t *testing.T) { t.Parallel() + const ( cafile = "../../helper/tlsutil/testdata/ca.pem" foocert = "../../helper/tlsutil/testdata/nomad-foo.pem" fookey = "../../helper/tlsutil/testdata/nomad-foo-key.pem" - maxConns = 10 // limit must be < this for testing + maxConns = 10 // limit must be < this for testing + bufSize = 1 * 1024 // enough for 429 error message ) cases := []struct { @@ -954,11 +964,14 @@ func TestHTTPServer_Limits_OK(t *testing.T) { conn, err := net.DialTimeout("tcp", a.Server.Addr, deadline) require.NoError(t, err) - defer conn.Close() + defer func() { + require.NoError(t, conn.Close()) + }() buf := []byte{0} readDeadline := time.Now().Add(deadline) - conn.SetReadDeadline(readDeadline) + err = conn.SetReadDeadline(readDeadline) + require.NoError(t, err) n, err := conn.Read(buf) require.Zero(t, n) if assertTimeout { @@ -1011,12 +1024,12 @@ func TestHTTPServer_Limits_OK(t *testing.T) { for i := 0; i < maxConns; i++ { conns[i], err = net.DialTimeout("tcp", addr, 1*time.Second) require.NoError(t, err) - defer conns[i].Close() go func(i int) { buf := []byte{0} readDeadline := time.Now().Add(1 * time.Second) - conns[i].SetReadDeadline(readDeadline) + err = conns[i].SetReadDeadline(readDeadline) + require.NoError(t, err) n, err := conns[i].Read(buf) if n > 0 { errCh <- fmt.Errorf("n > 0: %d", n) @@ -1036,18 +1049,37 @@ func TestHTTPServer_Limits_OK(t *testing.T) { "error does not wrap os.ErrDeadlineExceeded: (%T) %v", err, err) } } + + for i := 0; i < maxConns; i++ { + require.NoError(t, conns[i].Close()) + } } - assertLimit := func(t *testing.T, addr string, limit int) { + dial := func(t *testing.T, addr string, useTLS bool) net.Conn { + if useTLS { + cert, err := tls.LoadX509KeyPair(foocert, fookey) + require.NoError(t, err) + conn, err := tls.Dial("tcp", addr, &tls.Config{ + Certificates: []tls.Certificate{cert}, + InsecureSkipVerify: true, // good enough + }) + require.NoError(t, err) + return conn + } else { + conn, err := net.DialTimeout("tcp", addr, 1*time.Second) + require.NoError(t, err) + return conn + } + } + + assertLimit := func(t *testing.T, addr string, limit int, useTLS bool) { var err error // Create limit connections conns := make([]net.Conn, limit) errCh := make(chan error, limit) for i := range conns { - conns[i], err = net.DialTimeout("tcp", addr, 1*time.Second) - require.NoError(t, err) - defer conns[i].Close() + conns[i] = dial(t, addr, useTLS) go func(i int) { buf := []byte{0} @@ -1067,26 +1099,30 @@ func TestHTTPServer_Limits_OK(t *testing.T) { } // Assert a new connection is dropped - conn, err := net.DialTimeout("tcp", addr, 1*time.Second) - require.NoError(t, err) - defer conn.Close() + conn := dial(t, addr, useTLS) + + defer func() { + require.NoError(t, conn.Close()) + }() - buf := []byte{0} deadline := time.Now().Add(10 * time.Second) - conn.SetReadDeadline(deadline) - n, err := conn.Read(buf) - require.Zero(t, n) + require.NoError(t, conn.SetReadDeadline(deadline)) - // Soft-fail as following assertion helps with debugging - assert.Equal(t, io.EOF, err) + buf := make([]byte, bufSize) + n, err := conn.Read(buf) + + require.NoError(t, err) + require.NotZero(t, n) + require.True(t, strings.HasPrefix(string(buf), "HTTP/1.1 429 Too Many Requests")) // Assert existing connections are ok require.Len(t, errCh, 0) // Cleanup for _, conn := range conns { - conn.Close() + require.NoError(t, conn.Close()) } + for range conns { err := <-errCh require.Contains(t, err.Error(), "use of closed network connection") @@ -1095,7 +1131,7 @@ func TestHTTPServer_Limits_OK(t *testing.T) { for i := range cases { tc := cases[i] - name := fmt.Sprintf("%d-tls-%t-timeout-%s-limit-%v", i, tc.tls, tc.timeout, tc.limit) + name := fmt.Sprintf("%d-tls-%t-timeout-%s-limit-%v", i, tc.tls, tc.timeout, limitStr(tc.limit)) t.Run(name, func(t *testing.T) { t.Parallel() @@ -1114,21 +1150,24 @@ func TestHTTPServer_Limits_OK(t *testing.T) { } c.Limits.HTTPSHandshakeTimeout = tc.timeout c.Limits.HTTPMaxConnsPerClient = tc.limit + c.LogLevel = "ERROR" }) - defer s.Shutdown() + defer func() { + require.NoError(t, s.Shutdown()) + }() assertTimeout(t, s, tc.assertTimeout, tc.timeout) if tc.assertLimit { // There's a race between assertTimeout(false) closing // its connection and the HTTP server noticing and - // untracking it. Since there's no way to coordiante + // untracking it. Since there's no way to coordinate // when this occurs, sleeping is the only way to avoid // asserting limits before the timed out connection is // untracked. time.Sleep(1 * time.Second) - assertLimit(t, s.Server.Addr, *tc.limit) + assertLimit(t, s.Server.Addr, *tc.limit, tc.tls) } else { assertNoLimit(t, s.Server.Addr) } diff --git a/go.mod b/go.mod index 3f2052be3..16db42de7 100644 --- a/go.mod +++ b/go.mod @@ -57,7 +57,7 @@ require ( github.com/hashicorp/cronexpr v1.1.1 github.com/hashicorp/go-checkpoint v0.0.0-20171009173528-1545e56e46de github.com/hashicorp/go-cleanhttp v0.5.1 - github.com/hashicorp/go-connlimit v0.2.0 + github.com/hashicorp/go-connlimit v0.3.0 github.com/hashicorp/go-cty-funcs v0.0.0-20200930094925-2721b1e36840 github.com/hashicorp/go-discover v0.0.0-20200812215701-c4b85f6ed31f github.com/hashicorp/go-envparse v0.0.0-20180119215841-310ca1881b22 diff --git a/go.sum b/go.sum index bbb261695..955f1254d 100644 --- a/go.sum +++ b/go.sum @@ -360,6 +360,8 @@ github.com/hashicorp/go-cleanhttp v0.5.1 h1:dH3aiDG9Jvb5r5+bYHsikaOUIpcM0xvgMXVo github.com/hashicorp/go-cleanhttp v0.5.1/go.mod h1:JpRdi6/HCYpAwUzNwuwqhbovhLtngrth3wmdIIUrZ80= github.com/hashicorp/go-connlimit v0.2.0 h1:OZjcfNxH/hPh/bT2Iw5yOJcLzz+zuIWpsp3I1S4Pjw4= github.com/hashicorp/go-connlimit v0.2.0/go.mod h1:OUj9FGL1tPIhl/2RCfzYHrIiWj+VVPGNyVPnUX8AqS0= +github.com/hashicorp/go-connlimit v0.3.0 h1:oAojHGjFxUTTTA8c5XXnDqWJ2HLuWbDiBPTpWvNzvqM= +github.com/hashicorp/go-connlimit v0.3.0/go.mod h1:OUj9FGL1tPIhl/2RCfzYHrIiWj+VVPGNyVPnUX8AqS0= github.com/hashicorp/go-cty-funcs v0.0.0-20200930094925-2721b1e36840 h1:kgvybwEeu0SXktbB2y3uLHX9lklLo+nzUwh59A3jzQc= github.com/hashicorp/go-cty-funcs v0.0.0-20200930094925-2721b1e36840/go.mod h1:Abjk0jbRkDaNCzsRhOv2iDCofYpX1eVsjozoiK63qLA= github.com/hashicorp/go-discover v0.0.0-20200812215701-c4b85f6ed31f h1:7WFMVeuJQp6BkzuTv9O52pzwtEFVUJubKYN+zez8eTI= diff --git a/vendor/github.com/hashicorp/go-connlimit/LICENSE b/vendor/github.com/hashicorp/go-connlimit/LICENSE new file mode 100644 index 000000000..a612ad981 --- /dev/null +++ b/vendor/github.com/hashicorp/go-connlimit/LICENSE @@ -0,0 +1,373 @@ +Mozilla Public License Version 2.0 +================================== + +1. Definitions +-------------- + +1.1. "Contributor" + means each individual or legal entity that creates, contributes to + the creation of, or owns Covered Software. + +1.2. "Contributor Version" + means the combination of the Contributions of others (if any) used + by a Contributor and that particular Contributor's Contribution. + +1.3. "Contribution" + means Covered Software of a particular Contributor. + +1.4. "Covered Software" + means Source Code Form to which the initial Contributor has attached + the notice in Exhibit A, the Executable Form of such Source Code + Form, and Modifications of such Source Code Form, in each case + including portions thereof. + +1.5. "Incompatible With Secondary Licenses" + means + + (a) that the initial Contributor has attached the notice described + in Exhibit B to the Covered Software; or + + (b) that the Covered Software was made available under the terms of + version 1.1 or earlier of the License, but not also under the + terms of a Secondary License. + +1.6. "Executable Form" + means any form of the work other than Source Code Form. + +1.7. "Larger Work" + means a work that combines Covered Software with other material, in + a separate file or files, that is not Covered Software. + +1.8. "License" + means this document. + +1.9. "Licensable" + means having the right to grant, to the maximum extent possible, + whether at the time of the initial grant or subsequently, any and + all of the rights conveyed by this License. + +1.10. "Modifications" + means any of the following: + + (a) any file in Source Code Form that results from an addition to, + deletion from, or modification of the contents of Covered + Software; or + + (b) any new file in Source Code Form that contains any Covered + Software. + +1.11. "Patent Claims" of a Contributor + means any patent claim(s), including without limitation, method, + process, and apparatus claims, in any patent Licensable by such + Contributor that would be infringed, but for the grant of the + License, by the making, using, selling, offering for sale, having + made, import, or transfer of either its Contributions or its + Contributor Version. + +1.12. "Secondary License" + means either the GNU General Public License, Version 2.0, the GNU + Lesser General Public License, Version 2.1, the GNU Affero General + Public License, Version 3.0, or any later versions of those + licenses. + +1.13. "Source Code Form" + means the form of the work preferred for making modifications. + +1.14. "You" (or "Your") + means an individual or a legal entity exercising rights under this + License. For legal entities, "You" includes any entity that + controls, is controlled by, or is under common control with You. For + purposes of this definition, "control" means (a) the power, direct + or indirect, to cause the direction or management of such entity, + whether by contract or otherwise, or (b) ownership of more than + fifty percent (50%) of the outstanding shares or beneficial + ownership of such entity. + +2. License Grants and Conditions +-------------------------------- + +2.1. Grants + +Each Contributor hereby grants You a world-wide, royalty-free, +non-exclusive license: + +(a) under intellectual property rights (other than patent or trademark) + Licensable by such Contributor to use, reproduce, make available, + modify, display, perform, distribute, and otherwise exploit its + Contributions, either on an unmodified basis, with Modifications, or + as part of a Larger Work; and + +(b) under Patent Claims of such Contributor to make, use, sell, offer + for sale, have made, import, and otherwise transfer either its + Contributions or its Contributor Version. + +2.2. Effective Date + +The licenses granted in Section 2.1 with respect to any Contribution +become effective for each Contribution on the date the Contributor first +distributes such Contribution. + +2.3. Limitations on Grant Scope + +The licenses granted in this Section 2 are the only rights granted under +this License. No additional rights or licenses will be implied from the +distribution or licensing of Covered Software under this License. +Notwithstanding Section 2.1(b) above, no patent license is granted by a +Contributor: + +(a) for any code that a Contributor has removed from Covered Software; + or + +(b) for infringements caused by: (i) Your and any other third party's + modifications of Covered Software, or (ii) the combination of its + Contributions with other software (except as part of its Contributor + Version); or + +(c) under Patent Claims infringed by Covered Software in the absence of + its Contributions. + +This License does not grant any rights in the trademarks, service marks, +or logos of any Contributor (except as may be necessary to comply with +the notice requirements in Section 3.4). + +2.4. Subsequent Licenses + +No Contributor makes additional grants as a result of Your choice to +distribute the Covered Software under a subsequent version of this +License (see Section 10.2) or under the terms of a Secondary License (if +permitted under the terms of Section 3.3). + +2.5. Representation + +Each Contributor represents that the Contributor believes its +Contributions are its original creation(s) or it has sufficient rights +to grant the rights to its Contributions conveyed by this License. + +2.6. Fair Use + +This License is not intended to limit any rights You have under +applicable copyright doctrines of fair use, fair dealing, or other +equivalents. + +2.7. Conditions + +Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted +in Section 2.1. + +3. Responsibilities +------------------- + +3.1. Distribution of Source Form + +All distribution of Covered Software in Source Code Form, including any +Modifications that You create or to which You contribute, must be under +the terms of this License. You must inform recipients that the Source +Code Form of the Covered Software is governed by the terms of this +License, and how they can obtain a copy of this License. You may not +attempt to alter or restrict the recipients' rights in the Source Code +Form. + +3.2. Distribution of Executable Form + +If You distribute Covered Software in Executable Form then: + +(a) such Covered Software must also be made available in Source Code + Form, as described in Section 3.1, and You must inform recipients of + the Executable Form how they can obtain a copy of such Source Code + Form by reasonable means in a timely manner, at a charge no more + than the cost of distribution to the recipient; and + +(b) You may distribute such Executable Form under the terms of this + License, or sublicense it under different terms, provided that the + license for the Executable Form does not attempt to limit or alter + the recipients' rights in the Source Code Form under this License. + +3.3. Distribution of a Larger Work + +You may create and distribute a Larger Work under terms of Your choice, +provided that You also comply with the requirements of this License for +the Covered Software. If the Larger Work is a combination of Covered +Software with a work governed by one or more Secondary Licenses, and the +Covered Software is not Incompatible With Secondary Licenses, this +License permits You to additionally distribute such Covered Software +under the terms of such Secondary License(s), so that the recipient of +the Larger Work may, at their option, further distribute the Covered +Software under the terms of either this License or such Secondary +License(s). + +3.4. Notices + +You may not remove or alter the substance of any license notices +(including copyright notices, patent notices, disclaimers of warranty, +or limitations of liability) contained within the Source Code Form of +the Covered Software, except that You may alter any license notices to +the extent required to remedy known factual inaccuracies. + +3.5. Application of Additional Terms + +You may choose to offer, and to charge a fee for, warranty, support, +indemnity or liability obligations to one or more recipients of Covered +Software. However, You may do so only on Your own behalf, and not on +behalf of any Contributor. You must make it absolutely clear that any +such warranty, support, indemnity, or liability obligation is offered by +You alone, and You hereby agree to indemnify every Contributor for any +liability incurred by such Contributor as a result of warranty, support, +indemnity or liability terms You offer. You may include additional +disclaimers of warranty and limitations of liability specific to any +jurisdiction. + +4. Inability to Comply Due to Statute or Regulation +--------------------------------------------------- + +If it is impossible for You to comply with any of the terms of this +License with respect to some or all of the Covered Software due to +statute, judicial order, or regulation then You must: (a) comply with +the terms of this License to the maximum extent possible; and (b) +describe the limitations and the code they affect. Such description must +be placed in a text file included with all distributions of the Covered +Software under this License. Except to the extent prohibited by statute +or regulation, such description must be sufficiently detailed for a +recipient of ordinary skill to be able to understand it. + +5. Termination +-------------- + +5.1. The rights granted under this License will terminate automatically +if You fail to comply with any of its terms. However, if You become +compliant, then the rights granted under this License from a particular +Contributor are reinstated (a) provisionally, unless and until such +Contributor explicitly and finally terminates Your grants, and (b) on an +ongoing basis, if such Contributor fails to notify You of the +non-compliance by some reasonable means prior to 60 days after You have +come back into compliance. Moreover, Your grants from a particular +Contributor are reinstated on an ongoing basis if such Contributor +notifies You of the non-compliance by some reasonable means, this is the +first time You have received notice of non-compliance with this License +from such Contributor, and You become compliant prior to 30 days after +Your receipt of the notice. + +5.2. If You initiate litigation against any entity by asserting a patent +infringement claim (excluding declaratory judgment actions, +counter-claims, and cross-claims) alleging that a Contributor Version +directly or indirectly infringes any patent, then the rights granted to +You by any and all Contributors for the Covered Software under Section +2.1 of this License shall terminate. + +5.3. In the event of termination under Sections 5.1 or 5.2 above, all +end user license agreements (excluding distributors and resellers) which +have been validly granted by You or Your distributors under this License +prior to termination shall survive termination. + +************************************************************************ +* * +* 6. Disclaimer of Warranty * +* ------------------------- * +* * +* Covered Software is provided under this License on an "as is" * +* basis, without warranty of any kind, either expressed, implied, or * +* statutory, including, without limitation, warranties that the * +* Covered Software is free of defects, merchantable, fit for a * +* particular purpose or non-infringing. The entire risk as to the * +* quality and performance of the Covered Software is with You. * +* Should any Covered Software prove defective in any respect, You * +* (not any Contributor) assume the cost of any necessary servicing, * +* repair, or correction. This disclaimer of warranty constitutes an * +* essential part of this License. No use of any Covered Software is * +* authorized under this License except under this disclaimer. * +* * +************************************************************************ + +************************************************************************ +* * +* 7. Limitation of Liability * +* -------------------------- * +* * +* Under no circumstances and under no legal theory, whether tort * +* (including negligence), contract, or otherwise, shall any * +* Contributor, or anyone who distributes Covered Software as * +* permitted above, be liable to You for any direct, indirect, * +* special, incidental, or consequential damages of any character * +* including, without limitation, damages for lost profits, loss of * +* goodwill, work stoppage, computer failure or malfunction, or any * +* and all other commercial damages or losses, even if such party * +* shall have been informed of the possibility of such damages. This * +* limitation of liability shall not apply to liability for death or * +* personal injury resulting from such party's negligence to the * +* extent applicable law prohibits such limitation. Some * +* jurisdictions do not allow the exclusion or limitation of * +* incidental or consequential damages, so this exclusion and * +* limitation may not apply to You. * +* * +************************************************************************ + +8. Litigation +------------- + +Any litigation relating to this License may be brought only in the +courts of a jurisdiction where the defendant maintains its principal +place of business and such litigation shall be governed by laws of that +jurisdiction, without reference to its conflict-of-law provisions. +Nothing in this Section shall prevent a party's ability to bring +cross-claims or counter-claims. + +9. Miscellaneous +---------------- + +This License represents the complete agreement concerning the subject +matter hereof. If any provision of this License is held to be +unenforceable, such provision shall be reformed only to the extent +necessary to make it enforceable. Any law or regulation which provides +that the language of a contract shall be construed against the drafter +shall not be used to construe this License against a Contributor. + +10. Versions of the License +--------------------------- + +10.1. New Versions + +Mozilla Foundation is the license steward. Except as provided in Section +10.3, no one other than the license steward has the right to modify or +publish new versions of this License. Each version will be given a +distinguishing version number. + +10.2. Effect of New Versions + +You may distribute the Covered Software under the terms of the version +of the License under which You originally received the Covered Software, +or under the terms of any subsequent version published by the license +steward. + +10.3. Modified Versions + +If you create software not governed by this License, and you want to +create a new license for such software, you may create and use a +modified version of this License if you rename the license and remove +any references to the name of the license steward (except to note that +such modified license differs from this License). + +10.4. Distributing Source Code Form that is Incompatible With Secondary +Licenses + +If You choose to distribute Source Code Form that is Incompatible With +Secondary Licenses under the terms of this version of the License, the +notice described in Exhibit B of this License must be attached. + +Exhibit A - Source Code Form License Notice +------------------------------------------- + + This Source Code Form is subject to the terms of the Mozilla Public + License, v. 2.0. If a copy of the MPL was not distributed with this + file, You can obtain one at http://mozilla.org/MPL/2.0/. + +If it is not possible or desirable to put the notice in a particular +file, then You may include the notice in a location (such as a LICENSE +file in a relevant directory) where a recipient would be likely to look +for such a notice. + +You may add additional accurate notices of copyright ownership. + +Exhibit B - "Incompatible With Secondary Licenses" Notice +--------------------------------------------------------- + + This Source Code Form is "Incompatible With Secondary Licenses", as + defined by the Mozilla Public License, v. 2.0. diff --git a/vendor/github.com/hashicorp/go-connlimit/NOTICE.md b/vendor/github.com/hashicorp/go-connlimit/NOTICE.md new file mode 100644 index 000000000..245913b14 --- /dev/null +++ b/vendor/github.com/hashicorp/go-connlimit/NOTICE.md @@ -0,0 +1,3 @@ +Copyright © 2020 HashiCorp, Inc. + +This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this project, you can obtain one at http://mozilla.org/MPL/2.0/. diff --git a/vendor/github.com/hashicorp/go-connlimit/README.md b/vendor/github.com/hashicorp/go-connlimit/README.md index 99d2d95b0..fd01fc469 100644 --- a/vendor/github.com/hashicorp/go-connlimit/README.md +++ b/vendor/github.com/hashicorp/go-connlimit/README.md @@ -11,7 +11,7 @@ the resources that can be consumed by a single client. ### TCP Server -``` +```go // During server setup: s.limiter = NewLimiter(Config{ MaxConnsPerClientIP: 10, @@ -19,7 +19,7 @@ s.limiter = NewLimiter(Config{ ``` -``` +```go // handleConn is called in its own goroutine for each net.Conn accepted by // a net.Listener. func (s *Server) handleConn(conn net.Conn) { @@ -53,7 +53,7 @@ func (s *Server) handleConn(conn net.Conn) { ### HTTP Server -``` +```go lim := NewLimiter(Config{ MaxConnsPerClientIP: 10, }) diff --git a/vendor/github.com/hashicorp/go-connlimit/connlimit.go b/vendor/github.com/hashicorp/go-connlimit/connlimit.go index d445df103..248d9693a 100644 --- a/vendor/github.com/hashicorp/go-connlimit/connlimit.go +++ b/vendor/github.com/hashicorp/go-connlimit/connlimit.go @@ -2,16 +2,23 @@ package connlimit import ( "errors" + "fmt" "net" "net/http" "sync" "sync/atomic" + "time" ) var ( // ErrPerClientIPLimitReached is returned if accepting a new conn would exceed // the per-client-ip limit set. ErrPerClientIPLimitReached = errors.New("client connection limit reached") + tooManyConnsMsg = "Your IP is issuing too many concurrent connections, please rate limit your calls\n" + tooManyRequestsResponse = []byte(fmt.Sprintf("HTTP/1.1 429 Too Many Requests\r\n"+ + "Content-Type: text/plain\r\n"+ + "Content-Length: %d\r\n"+ + "Connection: close\r\n\r\n%s", len(tooManyConnsMsg), tooManyConnsMsg)) ) // Limiter implements a simple limiter that tracks the number of connections @@ -173,7 +180,7 @@ func (l *Limiter) SetConfig(c Config) { l.cfg.Store(c) } -// HTTPConnStateFunc returns a func that can be passed as the ConnState field of +// HTTPConnStateFuncWithErrorHandler returns a func that can be passed as the ConnState field of // an http.Server. This intercepts new HTTP connections to the server and // applies the limiting to new connections. // @@ -181,13 +188,15 @@ func (l *Limiter) SetConfig(c Config) { // in the limiter as if it was closed. Servers that use Hijacking must implement // their own calls if they need to continue limiting the number of concurrent // hijacked connections. -func (l *Limiter) HTTPConnStateFunc() func(net.Conn, http.ConnState) { +// errorHandler MUST close the connection itself +func (l *Limiter) HTTPConnStateFuncWithErrorHandler(errorHandler func(error, net.Conn)) func(net.Conn, http.ConnState) { + return func(conn net.Conn, state http.ConnState) { switch state { case http.StateNew: _, err := l.Accept(conn) if err != nil { - conn.Close() + errorHandler(err, conn) } case http.StateHijacked: l.freeConn(conn) @@ -199,3 +208,26 @@ func (l *Limiter) HTTPConnStateFunc() func(net.Conn, http.ConnState) { } } } + +// HTTPConnStateFunc is here for ascending compatibility reasons. +func (l *Limiter) HTTPConnStateFunc() func(net.Conn, http.ConnState) { + return l.HTTPConnStateFuncWithErrorHandler(func(err error, conn net.Conn) { + conn.Close() + }) +} + +// HTTPConnStateFuncWithDefault429Handler return an HTTP 429 if too many connections occur. +// BEWARE that returning HTTP 429 is done on critical path, you might choose to use +// HTTPConnStateFuncWithErrorHandler if you want to use a non-blocking strategy. +func (l *Limiter) HTTPConnStateFuncWithDefault429Handler(writeDeadlineMaxDelay time.Duration) func(net.Conn, http.ConnState) { + return l.HTTPConnStateFuncWithErrorHandler(func(err error, conn net.Conn) { + if err == ErrPerClientIPLimitReached { + // We don't care about slow players + if writeDeadlineMaxDelay > 0 { + conn.SetDeadline(time.Now().Add(writeDeadlineMaxDelay)) + } + conn.Write(tooManyRequestsResponse) + } + conn.Close() + }) +} diff --git a/vendor/modules.txt b/vendor/modules.txt index 44acfd572..de53d037c 100644 --- a/vendor/modules.txt +++ b/vendor/modules.txt @@ -384,7 +384,7 @@ github.com/hashicorp/go-checkpoint # github.com/hashicorp/go-cleanhttp v0.5.1 ## explicit github.com/hashicorp/go-cleanhttp -# github.com/hashicorp/go-connlimit v0.2.0 +# github.com/hashicorp/go-connlimit v0.3.0 ## explicit github.com/hashicorp/go-connlimit # github.com/hashicorp/go-cty-funcs v0.0.0-20200930094925-2721b1e36840