v/vlib/net/http/cookie.v

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V

// Copyright (c) 2019 Alexander Medvednikov. All rights reserved.
// Use of this source code is governed by an MIT license
// that can be found in the LICENSE file.
module http
import time
import strings
pub struct Cookie {
pub mut:
name string
value string
path string // optional
domain string // optional
expires time.Time // optional
raw_expires string // for reading cookies only. optional.
// max_age=0 means no 'Max-Age' attribute specified.
// max_age<0 means delete cookie now, equivalently 'Max-Age: 0'
// max_age>0 means Max-Age attribute present and given in seconds
max_age int
secure bool
http_only bool
same_site 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.
pub enum SameSite {
same_site_default_mode = 1
same_site_lax_mode
same_site_strict_mode
same_site_none_mode
}
// Parses all "Set-Cookie" values from the header `h` and
// returns the successfully parsed Cookies.
pub fn read_set_cookies(h map[string][]string) []&Cookie {
cookies_s := h['Set-Cookie']
cookie_count := cookies_s.len
if cookie_count == 0 {
return []
}
mut cookies := []&Cookie{}
for _, line in cookies_s {
c := parse_cookie(line) or { continue }
cookies << &c
}
return cookies
}
// 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
pub fn read_cookies(h map[string][]string, filter string) []&Cookie {
lines := h['Cookie']
if lines.len == 0 {
return []
}
mut cookies := []&Cookie{}
for _, line_ in lines {
mut line := line_.trim_space()
mut part := ''
for line.len > 0 {
if line.index_any(';') > 0 {
line_parts := line.split(';')
part = line_parts[0]
line = line_parts[1]
} else {
part = line
line = ''
}
part = part.trim_space()
if part.len == 0 {
continue
}
mut name := part
mut val := ''
if part.contains('=') {
val_parts := part.split('=')
name = val_parts[0]
val = val_parts[1]
}
if !is_cookie_name_valid(name) {
continue
}
if filter != '' && filter != name {
continue
}
val = parse_cookie_value(val, true) or { continue }
cookies << &Cookie{
name: name
value: val
}
}
}
return cookies
}
// 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.name is invalid, the empty string is returned.
pub fn (c &Cookie) str() string {
if !is_cookie_name_valid(c.name) {
return ''
}
// extra_cookie_length derived from typical length of cookie attributes
// see RFC 6265 Sec 4.1.
extra_cookie_length := 110
mut b := strings.new_builder(c.name.len + c.value.len + c.domain.len + c.path.len +
extra_cookie_length)
b.write_string(c.name)
b.write_string('=')
b.write_string(sanitize_cookie_value(c.value))
if c.path.len > 0 {
b.write_string('; path=')
b.write_string(sanitize_cookie_path(c.path))
}
if c.domain.len > 0 {
if valid_cookie_domain(c.domain) {
// A `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.
mut d := c.domain
if d[0] == `.` {
d = d.substr(1, d.len)
}
b.write_string('; domain=')
b.write_string(d)
} else {
// TODO: Log invalid cookie domain warning
}
}
if c.expires.year > 1600 {
e := c.expires
time_str := '$e.weekday_str(), $e.day.str() $e.smonth() $e.year $e.hhmmss() GMT'
b.write_string('; expires=')
b.write_string(time_str)
}
// TODO: Fix this. Techically a max age of 0 or less should be 0
// We need a way to not have a max age.
if c.max_age > 0 {
b.write_string('; Max-Age=')
b.write_string(c.max_age.str())
} else if c.max_age < 0 {
b.write_string('; Max-Age=0')
}
if c.http_only {
b.write_string('; HttpOnly')
}
if c.secure {
b.write_string('; Secure')
}
match c.same_site {
.same_site_default_mode {
b.write_string('; SameSite')
}
.same_site_none_mode {
b.write_string('; SameSite=None')
}
.same_site_lax_mode {
b.write_string('; SameSite=Lax')
}
.same_site_strict_mode {
b.write_string('; SameSite=Strict')
}
}
return b.str()
}
fn sanitize(valid fn (byte) bool, v string) string {
mut ok := true
for i in 0 .. v.len {
if valid(v[i]) {
continue
}
// TODO: Warn that we're dropping the invalid byte?
ok = false
break
}
if ok {
return v.clone()
}
return v.bytes().filter(valid(it)).bytestr()
}
fn sanitize_cookie_name(name string) string {
return name.replace_each(['\n', '-', '\r', '-'])
}
// https://tools.ietf.org/html/rfc6265#section-4.1.1
// cookie-value = *cookie-octet / ( DQUOTE *cookie-octet DQUOTE )
// cookie-octet = %x21 / %x23-2B / %x2D-3A / %x3C-5B / %x5D-7E
// ; US-ASCII characters excluding CTLs,
// ; whitespace DQUOTE, comma, semicolon,
// ; and backslash
// We loosen this as spaces and commas are common in cookie values
// but we produce a quoted cookie-value in when value starts or ends
// with a comma or space.
pub fn sanitize_cookie_value(v string) string {
val := sanitize(valid_cookie_value_byte, v)
if v.len == 0 {
return v
}
// Check for the existence of a space or comma
if val.starts_with(' ') || val.ends_with(' ') || val.starts_with(',') || val.ends_with(',') {
return '"$v"'
}
return v
}
fn sanitize_cookie_path(v string) string {
return sanitize(valid_cookie_path_byte, v)
}
fn valid_cookie_value_u8(b byte) bool {
return 0x20 <= b && b < 0x7f && b != `"` && b != `;` && b != `\\`
}
fn valid_cookie_path_u8(b byte) bool {
return 0x20 <= b && b < 0x7f && b != `!`
}
fn valid_cookie_domain(v string) bool {
if is_cookie_domain_name(v) {
return true
}
// TODO
// valid_ip := net.parse_ip(v) or {
// false
// }
// if valid_ip {
// return true
// }
return false
}
pub fn is_cookie_domain_name(_s string) bool {
mut s := _s
if s.len == 0 {
return false
}
if s.len > 255 {
return false
}
if s[0] == `.` {
s = s.substr(1, s.len)
}
mut last := `.`
mut ok := false
mut part_len := 0
for i, _ in s {
c := s[i]
if (`a` <= c && c <= `z`) || (`A` <= c && c <= `Z`) {
// No '_' allowed here (in contrast to package net).
ok = true
part_len++
} else if `0` <= c && c <= `9` {
// fine
part_len++
} else if c == `-` {
// Byte before dash cannot be dot.
if last == `.` {
return false
}
part_len++
} else if c == `.` {
// Byte before dot cannot be dot, dash.
if last == `.` || last == `-` {
return false
}
if part_len > 63 || part_len == 0 {
return false
}
part_len = 0
} else {
return false
}
last = c
}
if last == `-` || part_len > 63 {
return false
}
return ok
}
fn parse_cookie_value(_raw string, allow_double_quote bool) ?string {
mut raw := _raw
// Strip the quotes, if present
if allow_double_quote && raw.len > 1 && raw[0] == `"` && raw[raw.len - 1] == `"` {
raw = raw.substr(1, raw.len - 1)
}
for i in 0 .. raw.len {
if !valid_cookie_value_u8(raw[i]) {
return error('http.cookie: invalid cookie value')
}
}
return raw
}
fn is_cookie_name_valid(name string) bool {
if name == '' {
return false
}
for b in name {
if b < 33 || b > 126 {
return false
}
}
return true
}
fn parse_cookie(line string) ?Cookie {
mut parts := line.trim_space().split(';')
if parts.len == 1 && parts[0] == '' {
return error('malformed cookie')
}
parts[0] = parts[0].trim_space()
keyval := parts[0].split('=')
if keyval.len != 2 {
return error('malformed cookie')
}
name := keyval[0]
raw_value := keyval[1]
if !is_cookie_name_valid(name) {
return error('malformed cookie')
}
value := parse_cookie_value(raw_value, true) or { return error('malformed cookie') }
mut c := Cookie{
name: name
value: value
raw: line
}
for i, _ in parts {
parts[i] = parts[i].trim_space()
if parts[i].len == 0 {
continue
}
mut attr := parts[i]
mut raw_val := ''
if attr.contains('=') {
pieces := attr.split('=')
attr = pieces[0]
raw_val = pieces[1]
}
lower_attr := attr.to_lower()
val := parse_cookie_value(raw_val, false) or {
c.unparsed << parts[i]
continue
}
match lower_attr {
'samesite' {
lower_val := val.to_lower()
match lower_val {
'lax' { c.same_site = .same_site_lax_mode }
'strict' { c.same_site = .same_site_strict_mode }
'none' { c.same_site = .same_site_none_mode }
else { c.same_site = .same_site_default_mode }
}
}
'secure' {
c.secure = true
continue
}
'httponly' {
c.http_only = true
continue
}
'domain' {
c.domain = val
continue
}
'max-age' {
mut secs := val.int()
if secs != 0 && val[0] != `0` {
break
}
if secs <= 0 {
secs = -1
}
c.max_age = secs
continue
}
// TODO: Fix this once time works better
// 'expires' {
// c.raw_expires = val
// mut exptime := time.parse_iso(val)
// if exptime.year == 0 {
// exptime = time.parse_iso('Mon, 02-Jan-2006 15:04:05 MST')
// }
// c.expires = exptime
// continue
// }
'path' {
c.path = val
continue
}
else {
c.unparsed << parts[i]
}
}
}
return c
}