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-rw-r--r--src/net/http/cookie.go433
1 files changed, 433 insertions, 0 deletions
diff --git a/src/net/http/cookie.go b/src/net/http/cookie.go
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--- /dev/null
+++ b/src/net/http/cookie.go
@@ -0,0 +1,433 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http
+
+import (
+ "log"
+ "net"
+ "net/textproto"
+ "strconv"
+ "strings"
+ "time"
+)
+
+// A Cookie represents an HTTP cookie as sent in the Set-Cookie header of an
+// HTTP response or the Cookie header of an HTTP request.
+//
+// See https://tools.ietf.org/html/rfc6265 for details.
+type Cookie struct {
+ Name string
+ Value string
+
+ Path string // optional
+ Domain string // optional
+ Expires time.Time // optional
+ RawExpires string // for reading cookies only
+
+ // MaxAge=0 means no 'Max-Age' attribute specified.
+ // MaxAge<0 means delete cookie now, equivalently 'Max-Age: 0'
+ // MaxAge>0 means Max-Age attribute present and given in seconds
+ MaxAge int
+ Secure bool
+ HttpOnly bool
+ SameSite SameSite
+ Raw string
+ Unparsed []string // Raw text of unparsed attribute-value pairs
+}
+
+// SameSite allows a server to define a cookie attribute making it impossible for
+// the browser to send this cookie along with cross-site requests. The main
+// goal is to mitigate the risk of cross-origin information leakage, and provide
+// some protection against cross-site request forgery attacks.
+//
+// See https://tools.ietf.org/html/draft-ietf-httpbis-cookie-same-site-00 for details.
+type SameSite int
+
+const (
+ SameSiteDefaultMode SameSite = iota + 1
+ SameSiteLaxMode
+ SameSiteStrictMode
+ SameSiteNoneMode
+)
+
+// readSetCookies parses all "Set-Cookie" values from
+// the header h and returns the successfully parsed Cookies.
+func readSetCookies(h Header) []*Cookie {
+ cookieCount := len(h["Set-Cookie"])
+ if cookieCount == 0 {
+ return []*Cookie{}
+ }
+ cookies := make([]*Cookie, 0, cookieCount)
+ for _, line := range h["Set-Cookie"] {
+ parts := strings.Split(textproto.TrimString(line), ";")
+ if len(parts) == 1 && parts[0] == "" {
+ continue
+ }
+ parts[0] = textproto.TrimString(parts[0])
+ j := strings.Index(parts[0], "=")
+ if j < 0 {
+ continue
+ }
+ name, value := parts[0][:j], parts[0][j+1:]
+ if !isCookieNameValid(name) {
+ continue
+ }
+ value, ok := parseCookieValue(value, true)
+ if !ok {
+ continue
+ }
+ c := &Cookie{
+ Name: name,
+ Value: value,
+ Raw: line,
+ }
+ for i := 1; i < len(parts); i++ {
+ parts[i] = textproto.TrimString(parts[i])
+ if len(parts[i]) == 0 {
+ continue
+ }
+
+ attr, val := parts[i], ""
+ if j := strings.Index(attr, "="); j >= 0 {
+ attr, val = attr[:j], attr[j+1:]
+ }
+ lowerAttr := strings.ToLower(attr)
+ val, ok = parseCookieValue(val, false)
+ if !ok {
+ c.Unparsed = append(c.Unparsed, parts[i])
+ continue
+ }
+ switch lowerAttr {
+ case "samesite":
+ lowerVal := strings.ToLower(val)
+ switch lowerVal {
+ case "lax":
+ c.SameSite = SameSiteLaxMode
+ case "strict":
+ c.SameSite = SameSiteStrictMode
+ case "none":
+ c.SameSite = SameSiteNoneMode
+ default:
+ c.SameSite = SameSiteDefaultMode
+ }
+ continue
+ case "secure":
+ c.Secure = true
+ continue
+ case "httponly":
+ c.HttpOnly = true
+ continue
+ case "domain":
+ c.Domain = val
+ continue
+ case "max-age":
+ secs, err := strconv.Atoi(val)
+ if err != nil || secs != 0 && val[0] == '0' {
+ break
+ }
+ if secs <= 0 {
+ secs = -1
+ }
+ c.MaxAge = secs
+ continue
+ case "expires":
+ c.RawExpires = val
+ exptime, err := time.Parse(time.RFC1123, val)
+ if err != nil {
+ exptime, err = time.Parse("Mon, 02-Jan-2006 15:04:05 MST", val)
+ if err != nil {
+ c.Expires = time.Time{}
+ break
+ }
+ }
+ c.Expires = exptime.UTC()
+ continue
+ case "path":
+ c.Path = val
+ continue
+ }
+ c.Unparsed = append(c.Unparsed, parts[i])
+ }
+ cookies = append(cookies, c)
+ }
+ return cookies
+}
+
+// SetCookie adds a Set-Cookie header to the provided ResponseWriter's headers.
+// The provided cookie must have a valid Name. Invalid cookies may be
+// silently dropped.
+func SetCookie(w ResponseWriter, cookie *Cookie) {
+ if v := cookie.String(); v != "" {
+ w.Header().Add("Set-Cookie", v)
+ }
+}
+
+// String returns the serialization of the cookie for use in a Cookie
+// header (if only Name and Value are set) or a Set-Cookie response
+// header (if other fields are set).
+// If c is nil or c.Name is invalid, the empty string is returned.
+func (c *Cookie) String() string {
+ if c == nil || !isCookieNameValid(c.Name) {
+ return ""
+ }
+ // extraCookieLength derived from typical length of cookie attributes
+ // see RFC 6265 Sec 4.1.
+ const extraCookieLength = 110
+ var b strings.Builder
+ b.Grow(len(c.Name) + len(c.Value) + len(c.Domain) + len(c.Path) + extraCookieLength)
+ b.WriteString(c.Name)
+ b.WriteRune('=')
+ b.WriteString(sanitizeCookieValue(c.Value))
+
+ if len(c.Path) > 0 {
+ b.WriteString("; Path=")
+ b.WriteString(sanitizeCookiePath(c.Path))
+ }
+ if len(c.Domain) > 0 {
+ if validCookieDomain(c.Domain) {
+ // A c.Domain containing illegal characters is not
+ // sanitized but simply dropped which turns the cookie
+ // into a host-only cookie. A leading dot is okay
+ // but won't be sent.
+ d := c.Domain
+ if d[0] == '.' {
+ d = d[1:]
+ }
+ b.WriteString("; Domain=")
+ b.WriteString(d)
+ } else {
+ log.Printf("net/http: invalid Cookie.Domain %q; dropping domain attribute", c.Domain)
+ }
+ }
+ var buf [len(TimeFormat)]byte
+ if validCookieExpires(c.Expires) {
+ b.WriteString("; Expires=")
+ b.Write(c.Expires.UTC().AppendFormat(buf[:0], TimeFormat))
+ }
+ if c.MaxAge > 0 {
+ b.WriteString("; Max-Age=")
+ b.Write(strconv.AppendInt(buf[:0], int64(c.MaxAge), 10))
+ } else if c.MaxAge < 0 {
+ b.WriteString("; Max-Age=0")
+ }
+ if c.HttpOnly {
+ b.WriteString("; HttpOnly")
+ }
+ if c.Secure {
+ b.WriteString("; Secure")
+ }
+ switch c.SameSite {
+ case SameSiteDefaultMode:
+ // Skip, default mode is obtained by not emitting the attribute.
+ case SameSiteNoneMode:
+ b.WriteString("; SameSite=None")
+ case SameSiteLaxMode:
+ b.WriteString("; SameSite=Lax")
+ case SameSiteStrictMode:
+ b.WriteString("; SameSite=Strict")
+ }
+ return b.String()
+}
+
+// readCookies parses all "Cookie" values from the header h and
+// returns the successfully parsed Cookies.
+//
+// if filter isn't empty, only cookies of that name are returned
+func readCookies(h Header, filter string) []*Cookie {
+ lines := h["Cookie"]
+ if len(lines) == 0 {
+ return []*Cookie{}
+ }
+
+ cookies := make([]*Cookie, 0, len(lines)+strings.Count(lines[0], ";"))
+ for _, line := range lines {
+ line = textproto.TrimString(line)
+
+ var part string
+ for len(line) > 0 { // continue since we have rest
+ if splitIndex := strings.Index(line, ";"); splitIndex > 0 {
+ part, line = line[:splitIndex], line[splitIndex+1:]
+ } else {
+ part, line = line, ""
+ }
+ part = textproto.TrimString(part)
+ if len(part) == 0 {
+ continue
+ }
+ name, val := part, ""
+ if j := strings.Index(part, "="); j >= 0 {
+ name, val = name[:j], name[j+1:]
+ }
+ if !isCookieNameValid(name) {
+ continue
+ }
+ if filter != "" && filter != name {
+ continue
+ }
+ val, ok := parseCookieValue(val, true)
+ if !ok {
+ continue
+ }
+ cookies = append(cookies, &Cookie{Name: name, Value: val})
+ }
+ }
+ return cookies
+}
+
+// validCookieDomain reports whether v is a valid cookie domain-value.
+func validCookieDomain(v string) bool {
+ if isCookieDomainName(v) {
+ return true
+ }
+ if net.ParseIP(v) != nil && !strings.Contains(v, ":") {
+ return true
+ }
+ return false
+}
+
+// validCookieExpires reports whether v is a valid cookie expires-value.
+func validCookieExpires(t time.Time) bool {
+ // IETF RFC 6265 Section 5.1.1.5, the year must not be less than 1601
+ return t.Year() >= 1601
+}
+
+// isCookieDomainName reports whether s is a valid domain name or a valid
+// domain name with a leading dot '.'. It is almost a direct copy of
+// package net's isDomainName.
+func isCookieDomainName(s string) bool {
+ if len(s) == 0 {
+ return false
+ }
+ if len(s) > 255 {
+ return false
+ }
+
+ if s[0] == '.' {
+ // A cookie a domain attribute may start with a leading dot.
+ s = s[1:]
+ }
+ last := byte('.')
+ ok := false // Ok once we've seen a letter.
+ partlen := 0
+ for i := 0; i < len(s); i++ {
+ c := s[i]
+ switch {
+ default:
+ return false
+ case 'a' <= c && c <= 'z' || 'A' <= c && c <= 'Z':
+ // No '_' allowed here (in contrast to package net).
+ ok = true
+ partlen++
+ case '0' <= c && c <= '9':
+ // fine
+ partlen++
+ case c == '-':
+ // Byte before dash cannot be dot.
+ if last == '.' {
+ return false
+ }
+ partlen++
+ case c == '.':
+ // Byte before dot cannot be dot, dash.
+ if last == '.' || last == '-' {
+ return false
+ }
+ if partlen > 63 || partlen == 0 {
+ return false
+ }
+ partlen = 0
+ }
+ last = c
+ }
+ if last == '-' || partlen > 63 {
+ return false
+ }
+
+ return ok
+}
+
+var cookieNameSanitizer = strings.NewReplacer("\n", "-", "\r", "-")
+
+func sanitizeCookieName(n string) string {
+ return cookieNameSanitizer.Replace(n)
+}
+
+// sanitizeCookieValue produces a suitable cookie-value from v.
+// https://tools.ietf.org/html/rfc6265#section-4.1.1
+// cookie-value = *cookie-octet / ( DQUOTE *cookie-octet DQUOTE )
+// cookie-octet = %x21 / %x23-2B / %x2D-3A / %x3C-5B / %x5D-7E
+// ; US-ASCII characters excluding CTLs,
+// ; whitespace DQUOTE, comma, semicolon,
+// ; and backslash
+// We loosen this as spaces and commas are common in cookie values
+// but we produce a quoted cookie-value if and only if v contains
+// commas or spaces.
+// See https://golang.org/issue/7243 for the discussion.
+func sanitizeCookieValue(v string) string {
+ v = sanitizeOrWarn("Cookie.Value", validCookieValueByte, v)
+ if len(v) == 0 {
+ return v
+ }
+ if strings.IndexByte(v, ' ') >= 0 || strings.IndexByte(v, ',') >= 0 {
+ return `"` + v + `"`
+ }
+ return v
+}
+
+func validCookieValueByte(b byte) bool {
+ return 0x20 <= b && b < 0x7f && b != '"' && b != ';' && b != '\\'
+}
+
+// path-av = "Path=" path-value
+// path-value = <any CHAR except CTLs or ";">
+func sanitizeCookiePath(v string) string {
+ return sanitizeOrWarn("Cookie.Path", validCookiePathByte, v)
+}
+
+func validCookiePathByte(b byte) bool {
+ return 0x20 <= b && b < 0x7f && b != ';'
+}
+
+func sanitizeOrWarn(fieldName string, valid func(byte) bool, v string) string {
+ ok := true
+ for i := 0; i < len(v); i++ {
+ if valid(v[i]) {
+ continue
+ }
+ log.Printf("net/http: invalid byte %q in %s; dropping invalid bytes", v[i], fieldName)
+ ok = false
+ break
+ }
+ if ok {
+ return v
+ }
+ buf := make([]byte, 0, len(v))
+ for i := 0; i < len(v); i++ {
+ if b := v[i]; valid(b) {
+ buf = append(buf, b)
+ }
+ }
+ return string(buf)
+}
+
+func parseCookieValue(raw string, allowDoubleQuote bool) (string, bool) {
+ // Strip the quotes, if present.
+ if allowDoubleQuote && len(raw) > 1 && raw[0] == '"' && raw[len(raw)-1] == '"' {
+ raw = raw[1 : len(raw)-1]
+ }
+ for i := 0; i < len(raw); i++ {
+ if !validCookieValueByte(raw[i]) {
+ return "", false
+ }
+ }
+ return raw, true
+}
+
+func isCookieNameValid(raw string) bool {
+ if raw == "" {
+ return false
+ }
+ return strings.IndexFunc(raw, isNotToken) < 0
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 11:02:49 +0000