bitcoin/src/util/strencodings.cpp

547 lines
17 KiB
C++

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2022 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <span.h>
#include <util/strencodings.h>
#include <array>
#include <cassert>
#include <cstring>
#include <limits>
#include <optional>
#include <ostream>
#include <string>
#include <vector>
static const std::string CHARS_ALPHA_NUM = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
static const std::string SAFE_CHARS[] =
{
CHARS_ALPHA_NUM + " .,;-_/:?@()", // SAFE_CHARS_DEFAULT
CHARS_ALPHA_NUM + " .,;-_?@", // SAFE_CHARS_UA_COMMENT
CHARS_ALPHA_NUM + ".-_", // SAFE_CHARS_FILENAME
CHARS_ALPHA_NUM + "!*'();:@&=+$,/?#[]-_.~%", // SAFE_CHARS_URI
};
std::string SanitizeString(std::string_view str, int rule)
{
std::string result;
for (char c : str) {
if (SAFE_CHARS[rule].find(c) != std::string::npos) {
result.push_back(c);
}
}
return result;
}
const signed char p_util_hexdigit[256] =
{ -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
0,1,2,3,4,5,6,7,8,9,-1,-1,-1,-1,-1,-1,
-1,0xa,0xb,0xc,0xd,0xe,0xf,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,0xa,0xb,0xc,0xd,0xe,0xf,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1, };
signed char HexDigit(char c)
{
return p_util_hexdigit[(unsigned char)c];
}
bool IsHex(std::string_view str)
{
for (char c : str) {
if (HexDigit(c) < 0) return false;
}
return (str.size() > 0) && (str.size()%2 == 0);
}
bool IsHexNumber(std::string_view str)
{
if (str.substr(0, 2) == "0x") str.remove_prefix(2);
for (char c : str) {
if (HexDigit(c) < 0) return false;
}
// Return false for empty string or "0x".
return str.size() > 0;
}
template <typename Byte>
std::optional<std::vector<Byte>> TryParseHex(std::string_view str)
{
std::vector<Byte> vch;
vch.reserve(str.size() / 2); // two hex characters form a single byte
auto it = str.begin();
while (it != str.end()) {
if (IsSpace(*it)) {
++it;
continue;
}
auto c1 = HexDigit(*(it++));
if (it == str.end()) return std::nullopt;
auto c2 = HexDigit(*(it++));
if (c1 < 0 || c2 < 0) return std::nullopt;
vch.push_back(Byte(c1 << 4) | Byte(c2));
}
return vch;
}
template std::optional<std::vector<std::byte>> TryParseHex(std::string_view);
template std::optional<std::vector<uint8_t>> TryParseHex(std::string_view);
bool SplitHostPort(std::string_view in, uint16_t& portOut, std::string& hostOut)
{
bool valid = false;
size_t colon = in.find_last_of(':');
// if a : is found, and it either follows a [...], or no other : is in the string, treat it as port separator
bool fHaveColon = colon != in.npos;
bool fBracketed = fHaveColon && (in[0] == '[' && in[colon - 1] == ']'); // if there is a colon, and in[0]=='[', colon is not 0, so in[colon-1] is safe
bool fMultiColon{fHaveColon && colon != 0 && (in.find_last_of(':', colon - 1) != in.npos)};
if (fHaveColon && (colon == 0 || fBracketed || !fMultiColon)) {
uint16_t n;
if (ParseUInt16(in.substr(colon + 1), &n)) {
in = in.substr(0, colon);
portOut = n;
valid = (portOut != 0);
}
} else {
valid = true;
}
if (in.size() > 0 && in[0] == '[' && in[in.size() - 1] == ']') {
hostOut = in.substr(1, in.size() - 2);
} else {
hostOut = in;
}
return valid;
}
std::string EncodeBase64(Span<const unsigned char> input)
{
static const char *pbase64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
std::string str;
str.reserve(((input.size() + 2) / 3) * 4);
ConvertBits<8, 6, true>([&](int v) { str += pbase64[v]; }, input.begin(), input.end());
while (str.size() % 4) str += '=';
return str;
}
std::optional<std::vector<unsigned char>> DecodeBase64(std::string_view str)
{
static const int8_t decode64_table[256]{
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1,
-1, -1, -1, -1, -1, 0, 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, -1, -1, -1, -1, -1, -1, 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, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
};
if (str.size() % 4 != 0) return {};
/* One or two = characters at the end are permitted. */
if (str.size() >= 1 && str.back() == '=') str.remove_suffix(1);
if (str.size() >= 1 && str.back() == '=') str.remove_suffix(1);
std::vector<unsigned char> ret;
ret.reserve((str.size() * 3) / 4);
bool valid = ConvertBits<6, 8, false>(
[&](unsigned char c) { ret.push_back(c); },
str.begin(), str.end(),
[](char c) { return decode64_table[uint8_t(c)]; }
);
if (!valid) return {};
return ret;
}
std::string EncodeBase32(Span<const unsigned char> input, bool pad)
{
static const char *pbase32 = "abcdefghijklmnopqrstuvwxyz234567";
std::string str;
str.reserve(((input.size() + 4) / 5) * 8);
ConvertBits<8, 5, true>([&](int v) { str += pbase32[v]; }, input.begin(), input.end());
if (pad) {
while (str.size() % 8) {
str += '=';
}
}
return str;
}
std::string EncodeBase32(std::string_view str, bool pad)
{
return EncodeBase32(MakeUCharSpan(str), pad);
}
std::optional<std::vector<unsigned char>> DecodeBase32(std::string_view str)
{
static const int8_t decode32_table[256]{
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, -1, -1, -1, -1,
-1, -1, -1, -1, -1, 0, 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, -1, -1, -1, -1, -1, -1, 0, 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, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1
};
if (str.size() % 8 != 0) return {};
/* 1, 3, 4, or 6 padding '=' suffix characters are permitted. */
if (str.size() >= 1 && str.back() == '=') str.remove_suffix(1);
if (str.size() >= 2 && str.substr(str.size() - 2) == "==") str.remove_suffix(2);
if (str.size() >= 1 && str.back() == '=') str.remove_suffix(1);
if (str.size() >= 2 && str.substr(str.size() - 2) == "==") str.remove_suffix(2);
std::vector<unsigned char> ret;
ret.reserve((str.size() * 5) / 8);
bool valid = ConvertBits<5, 8, false>(
[&](unsigned char c) { ret.push_back(c); },
str.begin(), str.end(),
[](char c) { return decode32_table[uint8_t(c)]; }
);
if (!valid) return {};
return ret;
}
namespace {
template <typename T>
bool ParseIntegral(std::string_view str, T* out)
{
static_assert(std::is_integral<T>::value);
// Replicate the exact behavior of strtol/strtoll/strtoul/strtoull when
// handling leading +/- for backwards compatibility.
if (str.length() >= 2 && str[0] == '+' && str[1] == '-') {
return false;
}
const std::optional<T> opt_int = ToIntegral<T>((!str.empty() && str[0] == '+') ? str.substr(1) : str);
if (!opt_int) {
return false;
}
if (out != nullptr) {
*out = *opt_int;
}
return true;
}
}; // namespace
bool ParseInt32(std::string_view str, int32_t* out)
{
return ParseIntegral<int32_t>(str, out);
}
bool ParseInt64(std::string_view str, int64_t* out)
{
return ParseIntegral<int64_t>(str, out);
}
bool ParseUInt8(std::string_view str, uint8_t* out)
{
return ParseIntegral<uint8_t>(str, out);
}
bool ParseUInt16(std::string_view str, uint16_t* out)
{
return ParseIntegral<uint16_t>(str, out);
}
bool ParseUInt32(std::string_view str, uint32_t* out)
{
return ParseIntegral<uint32_t>(str, out);
}
bool ParseUInt64(std::string_view str, uint64_t* out)
{
return ParseIntegral<uint64_t>(str, out);
}
std::string FormatParagraph(std::string_view in, size_t width, size_t indent)
{
assert(width >= indent);
std::stringstream out;
size_t ptr = 0;
size_t indented = 0;
while (ptr < in.size())
{
size_t lineend = in.find_first_of('\n', ptr);
if (lineend == std::string::npos) {
lineend = in.size();
}
const size_t linelen = lineend - ptr;
const size_t rem_width = width - indented;
if (linelen <= rem_width) {
out << in.substr(ptr, linelen + 1);
ptr = lineend + 1;
indented = 0;
} else {
size_t finalspace = in.find_last_of(" \n", ptr + rem_width);
if (finalspace == std::string::npos || finalspace < ptr) {
// No place to break; just include the entire word and move on
finalspace = in.find_first_of("\n ", ptr);
if (finalspace == std::string::npos) {
// End of the string, just add it and break
out << in.substr(ptr);
break;
}
}
out << in.substr(ptr, finalspace - ptr) << "\n";
if (in[finalspace] == '\n') {
indented = 0;
} else if (indent) {
out << std::string(indent, ' ');
indented = indent;
}
ptr = finalspace + 1;
}
}
return out.str();
}
/** Upper bound for mantissa.
* 10^18-1 is the largest arbitrary decimal that will fit in a signed 64-bit integer.
* Larger integers cannot consist of arbitrary combinations of 0-9:
*
* 999999999999999999 1^18-1
* 9223372036854775807 (1<<63)-1 (max int64_t)
* 9999999999999999999 1^19-1 (would overflow)
*/
static const int64_t UPPER_BOUND = 1000000000000000000LL - 1LL;
/** Helper function for ParseFixedPoint */
static inline bool ProcessMantissaDigit(char ch, int64_t &mantissa, int &mantissa_tzeros)
{
if(ch == '0')
++mantissa_tzeros;
else {
for (int i=0; i<=mantissa_tzeros; ++i) {
if (mantissa > (UPPER_BOUND / 10LL))
return false; /* overflow */
mantissa *= 10;
}
mantissa += ch - '0';
mantissa_tzeros = 0;
}
return true;
}
bool ParseFixedPoint(std::string_view val, int decimals, int64_t *amount_out)
{
int64_t mantissa = 0;
int64_t exponent = 0;
int mantissa_tzeros = 0;
bool mantissa_sign = false;
bool exponent_sign = false;
int ptr = 0;
int end = val.size();
int point_ofs = 0;
if (ptr < end && val[ptr] == '-') {
mantissa_sign = true;
++ptr;
}
if (ptr < end)
{
if (val[ptr] == '0') {
/* pass single 0 */
++ptr;
} else if (val[ptr] >= '1' && val[ptr] <= '9') {
while (ptr < end && IsDigit(val[ptr])) {
if (!ProcessMantissaDigit(val[ptr], mantissa, mantissa_tzeros))
return false; /* overflow */
++ptr;
}
} else return false; /* missing expected digit */
} else return false; /* empty string or loose '-' */
if (ptr < end && val[ptr] == '.')
{
++ptr;
if (ptr < end && IsDigit(val[ptr]))
{
while (ptr < end && IsDigit(val[ptr])) {
if (!ProcessMantissaDigit(val[ptr], mantissa, mantissa_tzeros))
return false; /* overflow */
++ptr;
++point_ofs;
}
} else return false; /* missing expected digit */
}
if (ptr < end && (val[ptr] == 'e' || val[ptr] == 'E'))
{
++ptr;
if (ptr < end && val[ptr] == '+')
++ptr;
else if (ptr < end && val[ptr] == '-') {
exponent_sign = true;
++ptr;
}
if (ptr < end && IsDigit(val[ptr])) {
while (ptr < end && IsDigit(val[ptr])) {
if (exponent > (UPPER_BOUND / 10LL))
return false; /* overflow */
exponent = exponent * 10 + val[ptr] - '0';
++ptr;
}
} else return false; /* missing expected digit */
}
if (ptr != end)
return false; /* trailing garbage */
/* finalize exponent */
if (exponent_sign)
exponent = -exponent;
exponent = exponent - point_ofs + mantissa_tzeros;
/* finalize mantissa */
if (mantissa_sign)
mantissa = -mantissa;
/* convert to one 64-bit fixed-point value */
exponent += decimals;
if (exponent < 0)
return false; /* cannot represent values smaller than 10^-decimals */
if (exponent >= 18)
return false; /* cannot represent values larger than or equal to 10^(18-decimals) */
for (int i=0; i < exponent; ++i) {
if (mantissa > (UPPER_BOUND / 10LL) || mantissa < -(UPPER_BOUND / 10LL))
return false; /* overflow */
mantissa *= 10;
}
if (mantissa > UPPER_BOUND || mantissa < -UPPER_BOUND)
return false; /* overflow */
if (amount_out)
*amount_out = mantissa;
return true;
}
std::string ToLower(std::string_view str)
{
std::string r;
r.reserve(str.size());
for (auto ch : str) r += ToLower(ch);
return r;
}
std::string ToUpper(std::string_view str)
{
std::string r;
r.reserve(str.size());
for (auto ch : str) r += ToUpper(ch);
return r;
}
std::string Capitalize(std::string str)
{
if (str.empty()) return str;
str[0] = ToUpper(str.front());
return str;
}
namespace {
using ByteAsHex = std::array<char, 2>;
constexpr std::array<ByteAsHex, 256> CreateByteToHexMap()
{
constexpr char hexmap[16] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
std::array<ByteAsHex, 256> byte_to_hex{};
for (size_t i = 0; i < byte_to_hex.size(); ++i) {
byte_to_hex[i][0] = hexmap[i >> 4];
byte_to_hex[i][1] = hexmap[i & 15];
}
return byte_to_hex;
}
} // namespace
std::string HexStr(const Span<const uint8_t> s)
{
std::string rv(s.size() * 2, '\0');
static constexpr auto byte_to_hex = CreateByteToHexMap();
static_assert(sizeof(byte_to_hex) == 512);
char* it = rv.data();
for (uint8_t v : s) {
std::memcpy(it, byte_to_hex[v].data(), 2);
it += 2;
}
assert(it == rv.data() + rv.size());
return rv;
}
std::optional<uint64_t> ParseByteUnits(std::string_view str, ByteUnit default_multiplier)
{
if (str.empty()) {
return std::nullopt;
}
auto multiplier = default_multiplier;
char unit = str.back();
switch (unit) {
case 'k':
multiplier = ByteUnit::k;
break;
case 'K':
multiplier = ByteUnit::K;
break;
case 'm':
multiplier = ByteUnit::m;
break;
case 'M':
multiplier = ByteUnit::M;
break;
case 'g':
multiplier = ByteUnit::g;
break;
case 'G':
multiplier = ByteUnit::G;
break;
case 't':
multiplier = ByteUnit::t;
break;
case 'T':
multiplier = ByteUnit::T;
break;
default:
unit = 0;
break;
}
uint64_t unit_amount = static_cast<uint64_t>(multiplier);
auto parsed_num = ToIntegral<uint64_t>(unit ? str.substr(0, str.size() - 1) : str);
if (!parsed_num || parsed_num > std::numeric_limits<uint64_t>::max() / unit_amount) { // check overflow
return std::nullopt;
}
return *parsed_num * unit_amount;
}