summaryrefslogtreecommitdiff
path: root/client/httpclient.go
blob: fe6e2e533633454a71f09c6d697401fda023e79b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
package client

import (
	"context"
	"crypto/tls"
	"crypto/x509"
	"errors"
	"fmt"
	"net"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"time"

	"github.com/hashicorp/go-retryablehttp"
	"gitlab.com/gitlab-org/labkit/correlation"
	"gitlab.com/gitlab-org/labkit/tracing"
)

const (
	socketBaseUrl             = "http://unix"
	unixSocketProtocol        = "http+unix://"
	httpProtocol              = "http://"
	httpsProtocol             = "https://"
	defaultReadTimeoutSeconds = 300
)

var ErrCafileNotFound = errors.New("cafile not found")

type HttpClient struct {
	HTTPClient    *http.Client
	RetryableHTTP *retryablehttp.Client
	Host          string
}

type httpClientCfg struct {
	keyPath, certPath string
	caFile, caPath    string
}

func (hcc httpClientCfg) HaveCertAndKey() bool { return hcc.keyPath != "" && hcc.certPath != "" }

// HTTPClientOpt provides options for configuring an HttpClient
type HTTPClientOpt func(*httpClientCfg)

// WithClientCert will configure the HttpClient to provide client certificates
// when connecting to a server.
func WithClientCert(certPath, keyPath string) HTTPClientOpt {
	return func(hcc *httpClientCfg) {
		hcc.keyPath = keyPath
		hcc.certPath = certPath
	}
}

func validateCaFile(filename string) error {
	if filename == "" {
		return nil
	}

	if _, err := os.Stat(filename); err != nil {
		if os.IsNotExist(err) {
			return fmt.Errorf("cannot find cafile '%s': %w", filename, ErrCafileNotFound)
		}

		return err
	}

	return nil
}

// NewHTTPClientWithOpts builds an HTTP client using the provided options
func NewHTTPClientWithOpts(gitlabURL, gitlabRelativeURLRoot, caFile, caPath string, readTimeoutSeconds uint64, opts []HTTPClientOpt) (*HttpClient, error) {
	var transport *http.Transport
	var host string
	var err error
	if strings.HasPrefix(gitlabURL, unixSocketProtocol) {
		transport, host = buildSocketTransport(gitlabURL, gitlabRelativeURLRoot)
	} else if strings.HasPrefix(gitlabURL, httpProtocol) {
		transport, host = buildHttpTransport(gitlabURL)
	} else if strings.HasPrefix(gitlabURL, httpsProtocol) {
		err = validateCaFile(caFile)
		if err != nil {
			return nil, err
		}

		hcc := &httpClientCfg{
			caFile: caFile,
			caPath: caPath,
		}

		for _, opt := range opts {
			opt(hcc)
		}

		transport, host, err = buildHttpsTransport(*hcc, gitlabURL)
		if err != nil {
			return nil, err
		}
	} else {
		return nil, errors.New("unknown GitLab URL prefix")
	}

	c := &http.Client{
		Transport: correlation.NewInstrumentedRoundTripper(tracing.NewRoundTripper(transport)),
		Timeout:   readTimeout(readTimeoutSeconds),
	}

	client := &HttpClient{HTTPClient: c, Host: host}

	if os.Getenv("FF_GITLAB_SHELL_RETRYABLE_HTTP") == "1" {
		c := retryablehttp.NewClient()
		c.RetryMax = 2
		c.RetryWaitMax = 15 * time.Second
		c.Logger = nil
		c.HTTPClient.Transport = correlation.NewInstrumentedRoundTripper(tracing.NewRoundTripper(transport))
		c.HTTPClient.Timeout = readTimeout(readTimeoutSeconds)

		client = &HttpClient{RetryableHTTP: c, Host: host}
	}

	if client.HTTPClient == nil && client.RetryableHTTP == nil {
		panic("client/httpclient.go did not set http client")
	}

	return client, nil
}

func buildSocketTransport(gitlabURL, gitlabRelativeURLRoot string) (*http.Transport, string) {
	socketPath := strings.TrimPrefix(gitlabURL, unixSocketProtocol)

	transport := &http.Transport{
		DialContext: func(ctx context.Context, _, _ string) (net.Conn, error) {
			dialer := net.Dialer{}
			return dialer.DialContext(ctx, "unix", socketPath)
		},
	}

	host := socketBaseUrl
	gitlabRelativeURLRoot = strings.Trim(gitlabRelativeURLRoot, "/")
	if gitlabRelativeURLRoot != "" {
		host = host + "/" + gitlabRelativeURLRoot
	}

	return transport, host
}

func buildHttpsTransport(hcc httpClientCfg, gitlabURL string) (*http.Transport, string, error) {
	certPool, err := x509.SystemCertPool()
	if err != nil {
		certPool = x509.NewCertPool()
	}

	if hcc.caFile != "" {
		addCertToPool(certPool, hcc.caFile)
	}

	if hcc.caPath != "" {
		fis, _ := os.ReadDir(hcc.caPath)
		for _, fi := range fis {
			if fi.IsDir() {
				continue
			}

			addCertToPool(certPool, filepath.Join(hcc.caPath, fi.Name()))
		}
	}
	tlsConfig := &tls.Config{
		RootCAs:    certPool,
		MinVersion: tls.VersionTLS12,
	}

	if hcc.HaveCertAndKey() {
		cert, err := tls.LoadX509KeyPair(hcc.certPath, hcc.keyPath)
		if err != nil {
			return nil, "", err
		}
		tlsConfig.Certificates = []tls.Certificate{cert}
	}

	transport := &http.Transport{
		TLSClientConfig: tlsConfig,
	}

	return transport, gitlabURL, err
}

func addCertToPool(certPool *x509.CertPool, fileName string) {
	cert, err := os.ReadFile(fileName)
	if err == nil {
		certPool.AppendCertsFromPEM(cert)
	}
}

func buildHttpTransport(gitlabURL string) (*http.Transport, string) {
	return &http.Transport{}, gitlabURL
}

func readTimeout(timeoutSeconds uint64) time.Duration {
	if timeoutSeconds == 0 {
		timeoutSeconds = defaultReadTimeoutSeconds
	}

	return time.Duration(timeoutSeconds) * time.Second
}