From 7605b2ab5ea2cdd619fafbe5eea981f689865676 Mon Sep 17 00:00:00 2001 From: flu0r1ne Date: Sun, 27 Aug 2023 04:17:54 -0500 Subject: Encode key in base32 to exclude the Unix path sep --- src/crypto/curve25519.c | 4 +++- src/crypto/pubkey.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++-- src/crypto/pubkey.hpp | 7 +++++-- src/wg2nd.cpp | 21 +++++++++++++++++---- 4 files changed, 73 insertions(+), 9 deletions(-) diff --git a/src/crypto/curve25519.c b/src/crypto/curve25519.c index 7121d1e..2f6f5d6 100644 --- a/src/crypto/curve25519.c +++ b/src/crypto/curve25519.c @@ -79,7 +79,9 @@ static noinline void memzero_explicit(void *s, size_t count) asm volatile("": :"r"(s) : "memory"); } -#ifdef __SIZEOF_INT128__ +#ifdef __EMSCRIPTEN__ +#include "curve25519-fiat32.h" +#elif __SIZEOF_INT128__ #include "curve25519-hacl64.h" #else #include "curve25519-fiat32.h" diff --git a/src/crypto/pubkey.c b/src/crypto/pubkey.c index 1224b07..f43dbfc 100644 --- a/src/crypto/pubkey.c +++ b/src/crypto/pubkey.c @@ -1,9 +1,43 @@ #include "curve25519.h" #include "encoding.h" -int wg_pubkey_base64(char const * privkey, char * base64) { +#define WG_KEY_LEN_BASE32 (((WG_KEY_LEN + 4) / 5) * 8 + 1) +#define WG_KEY_LEN_BASE64 ((((WG_KEY_LEN) + 2) / 3) * 4 + 1) + +static inline void encode_base32(char dest[static 8], const uint8_t src[static 5]) { + const uint8_t input[] = { + src[0] >> 3, + ((src[0] & 0x07) << 2) | (src[1] >> 6), + (src[1] & 0x3F) >> 1, + ((src[1] & 0x01) << 4) | (src[2] >> 4), + ((src[2] & 0x0F) << 1) | (src[3] >> 7), + (src[3] & 0x7F) >> 2, + ((src[3] & 0x03) << 3) | (src[4] >> 5), + src[4] & 0x1F + }; + + for(unsigned int i = 0; i < 8; i++) + dest[i] = 'A' + input[i] - (((25 - input[i]) >> 8) & 41); +} + +void key_to_base32(char base32[static WG_KEY_LEN_BASE32], const uint8_t key[static WG_KEY_LEN]) +{ + unsigned int i; + + for (i = 0; i < WG_KEY_LEN / 5; ++i) + encode_base32(&base32[i * 8], &key[i * 5]); + encode_base32(&base32[i * 8], (const uint8_t[]){ key[i * 5 + 0], key[i * 5 + 1], 0, 0, 0 }); + base32[WG_KEY_LEN_BASE32 - 5] = '='; + base32[WG_KEY_LEN_BASE32 - 4] = '='; + base32[WG_KEY_LEN_BASE32 - 3] = '='; + base32[WG_KEY_LEN_BASE32 - 2] = '='; + base32[WG_KEY_LEN_BASE32 - 1] = '\0'; +} + +int wg_pubkey_base32(char const * privkey, char * base32) { uint8_t key[WG_KEY_LEN] __attribute((aligned(sizeof(uintptr_t)))); + char base64[WG_KEY_LEN_BASE64]; int i; for(i = 0; privkey[i] && i < WG_KEY_LEN_BASE64 - 1; i++) @@ -21,7 +55,19 @@ int wg_pubkey_base64(char const * privkey, char * base64) { curve25519_generate_public(key, key); - key_to_base64(base64, key); + key_to_base32(base32, key); + + return 0; +} + +int wg_key_convert_base32(char const * base64, char * base32) { + uint8_t key[WG_KEY_LEN] __attribute((aligned(sizeof(uintptr_t)))); + + if(!key_from_base64(key, base64)) { + return 1; + } + + key_to_base32(base32, key); return 0; } diff --git a/src/crypto/pubkey.hpp b/src/crypto/pubkey.hpp index 8596431..cb1f794 100644 --- a/src/crypto/pubkey.hpp +++ b/src/crypto/pubkey.hpp @@ -5,18 +5,21 @@ extern "C" { #endif #define WG_KEY_LEN_BASE64 ((((WG_KEY_LEN) + 2) / 3) * 4 + 1) +#define WG_KEY_LEN_BASE32 (((WG_KEY_LEN + 4) / 5) * 8 + 1) /* * wg_pubkey_base64 is a C++-compatible wrapper for the curve25519 public-key * derivation routines used natively in `wg(8)` * * PRIVKEY: a c-style string containing the base64-encoded private key - * BASE64: a c-style string of capacity WG_KEY_LEN_BASE64 containing the + * BASE32: a c-style string of capacity WG_KEY_LEN_BASE64 containing the * encoded public key * * returns: 0 on success * > 0 when an error occurs (due to improper key formatting) */ -int wg_pubkey_base64(char const * privkey, char * base64); +int wg_pubkey_base32(char const * privkey, char * base32); + +int wg_key_convert_base32(char const * base64, char * base32); } diff --git a/src/wg2nd.cpp b/src/wg2nd.cpp index cbe3c29..9397a0b 100644 --- a/src/wg2nd.cpp +++ b/src/wg2nd.cpp @@ -25,11 +25,11 @@ constexpr char const * SYMMETRIC_KEY_SUFFIX = ".symkey"; namespace wg2nd { std::string private_keyfile_name(std::string const & priv_key) { - char pub_key[WG_KEY_LEN_BASE64]; + char pub_key[WG_KEY_LEN_BASE32]; // Derive public key - if(wg_pubkey_base64(priv_key.c_str(), pub_key)) { - throw ParsingException("Private key is formatted improperly"); + if(wg_pubkey_base32(priv_key.c_str(), pub_key)) { + throw ParsingException("Private key is formatted improperly"); } std::string keyfile_name { pub_key }; @@ -38,6 +38,19 @@ namespace wg2nd { return keyfile_name; } + std::string public_keyfile_name(std::string const & pub_key) { + char pub_key32[WG_KEY_LEN_BASE32]; + + if(wg_key_convert_base32(pub_key.c_str(), pub_key32)) { + throw ParsingException("Public key for [Peer] " + pub_key + " is formatted improperly"); + } + + std::string keyfile_name { pub_key32 }; + keyfile_name.append(SYMMETRIC_KEY_SUFFIX); + + return keyfile_name; + } + uint32_t deterministic_fwmark(std::string const & interface_name) { constexpr uint8_t const SIP_KEY[8] = { 0x90, 0x08, 0x82, 0xd7, @@ -409,7 +422,7 @@ namespace wg2nd { } if(!peer.preshared_key.empty()) { - std::string filename = peer.public_key + SYMMETRIC_KEY_SUFFIX; + std::string filename = public_keyfile_name(peer.public_key); symmetric_keyfiles.push_back(SystemdFilespec { .name = filename, -- cgit v1.2.3