diff options
Diffstat (limited to 'src/openvpn/crypto.h')
| -rw-r--r-- | src/openvpn/crypto.h | 106 |
1 files changed, 68 insertions, 38 deletions
diff --git a/src/openvpn/crypto.h b/src/openvpn/crypto.h index 185bfd3..93c33c1 100644 --- a/src/openvpn/crypto.h +++ b/src/openvpn/crypto.h @@ -5,8 +5,8 @@ * packet encryption, packet authentication, and * packet compression. * - * Copyright (C) 2002-2018 OpenVPN Inc <sales@openvpn.net> - * Copyright (C) 2010-2018 Fox Crypto B.V. <openvpn@fox-it.com> + * Copyright (C) 2002-2021 OpenVPN Inc <sales@openvpn.net> + * Copyright (C) 2010-2021 Fox Crypto B.V. <openvpn@foxcrypto.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 @@ -38,8 +38,7 @@ * - \b HMAC, covering the ciphertext IV + ciphertext. The HMAC size depends * on the \c \-\-auth option. If \c \-\-auth \c none is specified, there is no * HMAC at all. - * - \b Ciphertext \b IV, if not disabled by \c \-\-no-iv. The IV size depends on - * the \c \-\-cipher option. + * - \b Ciphertext \b IV. The IV size depends on the \c \-\-cipher option. * - \b Packet \b ID, a 32-bit incrementing packet counter that provides replay * protection (if not disabled by \c \-\-no-replay). * - \b Timestamp, a 32-bit timestamp of the current time. @@ -123,8 +122,6 @@ #ifndef CRYPTO_H #define CRYPTO_H -#ifdef ENABLE_CRYPTO - #include "crypto_backend.h" #include "basic.h" #include "buffer.h" @@ -248,17 +245,13 @@ struct crypto_options #define CO_PACKET_ID_LONG_FORM (1<<0) /**< Bit-flag indicating whether to use * OpenVPN's long packet ID format. */ -#define CO_USE_IV (1<<1) - /**< Bit-flag indicating whether to - * generate a pseudo-random IV for each - * packet being encrypted. */ -#define CO_IGNORE_PACKET_ID (1<<2) +#define CO_IGNORE_PACKET_ID (1<<1) /**< Bit-flag indicating whether to ignore * the packet ID of a received packet. * This flag is used during processing * of the first packet received from a * client. */ -#define CO_MUTE_REPLAY_WARNINGS (1<<3) +#define CO_MUTE_REPLAY_WARNINGS (1<<2) /**< Bit-flag indicating not to display * replay warnings. */ unsigned int flags; /**< Bit-flags determining behavior of @@ -278,16 +271,16 @@ struct crypto_options #define RKF_INLINE (1<<1) void read_key_file(struct key2 *key2, const char *file, const unsigned int flags); +/** + * Write nkeys 1024-bits keys to file. + * + * @returns number of random bits written, or -1 on failure. + */ int write_key_file(const int nkeys, const char *filename); -int read_passphrase_hash(const char *passphrase_file, - const md_kt_t *digest, - uint8_t *output, - int len); - void generate_key_random(struct key *key, const struct key_type *kt); -void check_replay_iv_consistency(const struct key_type *kt, bool packet_id, bool use_iv); +void check_replay_consistency(const struct key_type *kt, bool packet_id); bool check_key(struct key *key, const struct key_type *kt); @@ -306,7 +299,7 @@ int read_key(struct key *key, const struct key_type *kt, struct buffer *buf); * @param authname The name of the HMAC digest to use * @param keysize The length of the cipher key to use, in bytes. Only valid * for ciphers that support variable length keys. - * @param tls_mode Specifies wether we are running in TLS mode, which allows + * @param tls_mode Specifies whether we are running in TLS mode, which allows * more ciphers than static key mode. * @param warn Print warnings when null cipher / auth is used. */ @@ -325,7 +318,7 @@ void free_key_ctx(struct key_ctx *ctx); void init_key_ctx_bi(struct key_ctx_bi *ctx, const struct key2 *key2, int key_direction, const struct key_type *kt, - const char *name); + const char *name); void free_key_ctx_bi(struct key_ctx_bi *ctx); @@ -421,13 +414,46 @@ bool crypto_check_replay(struct crypto_options *opt, /** Calculate crypto overhead and adjust frame to account for that */ void crypto_adjust_frame_parameters(struct frame *frame, const struct key_type *kt, - bool use_iv, bool packet_id, bool packet_id_long_form); /** Return the worst-case OpenVPN crypto overhead (in bytes) */ unsigned int crypto_max_overhead(void); +/** + * Generate a server key with enough randomness to fill a key struct + * and write to file. + * + * @param filename Filename of the server key file to create. + * @param pem_name The name to use in the PEM header/footer. + */ +void +write_pem_key_file(const char *filename, const char *key_name); + +/** + * Generate ephermal key material into the key structure + * + * @param key the key structure that will hold the key material + * @param pem_name the name used for logging + * @return true if key generation was successful + */ +bool +generate_ephemeral_key(struct buffer *key, const char *pem_name); + +/** + * Read key material from a PEM encoded files into the key structure + * @param key the key structure that will hold the key material + * @param pem_name the name used in the pem encoding start/end lines + * @param key_file name of the file to read or the key itself if + * key_inline is true + * @param key_inline True if key_file contains an inline key, False + * otherwise. + * @return true if reading into key was successful + */ +bool +read_pem_key_file(struct buffer *key, const char *pem_name, + const char *key_file, bool key_inline); + /* Minimum length of the nonce used by the PRNG */ #define NONCE_SECRET_LEN_MIN 16 @@ -465,6 +491,12 @@ void prng_bytes(uint8_t *output, int len); void prng_uninit(void); +/* an analogue to the random() function, but use prng_bytes */ +long int get_random(void); + +/** Print a cipher list entry */ +void print_cipher(const cipher_kt_t *cipher); + void test_crypto(struct crypto_options *co, struct frame *f); @@ -487,8 +519,9 @@ void key2_print(const struct key2 *k, const char *prefix1); void crypto_read_openvpn_key(const struct key_type *key_type, - struct key_ctx_bi *ctx, const char *key_file, const char *key_inline, - const int key_direction, const char *key_name, const char *opt_name); + struct key_ctx_bi *ctx, const char *key_file, + bool key_inline, const int key_direction, + const char *key_name, const char *opt_name); /* * Inline functions @@ -498,20 +531,7 @@ void crypto_read_openvpn_key(const struct key_type *key_type, * As memcmp(), but constant-time. * Returns 0 when data is equal, non-zero otherwise. */ -static inline int -memcmp_constant_time(const void *a, const void *b, size_t size) -{ - const uint8_t *a1 = a; - const uint8_t *b1 = b; - int ret = 0; - size_t i; - - for (i = 0; i < size; i++) { - ret |= *a1++ ^ *b1++; - } - - return ret; -} +int memcmp_constant_time(const void *a, const void *b, size_t size); static inline bool key_ctx_bi_defined(const struct key_ctx_bi *key) @@ -519,6 +539,16 @@ key_ctx_bi_defined(const struct key_ctx_bi *key) return key->encrypt.cipher || key->encrypt.hmac || key->decrypt.cipher || key->decrypt.hmac; } +/** + * To be used when printing a string that may contain inline data. + * + * If "is_inline" is true, return the inline tag. + * If "is_inline" is false and "str" is not NULL, return "str". + * Return the constant string "[NULL]" otherwise. + * + * @param str the original string to return when is_inline is false + * @param is_inline true when str contains an inline data of some sort + */ +const char *print_key_filename(const char *str, bool is_inline); -#endif /* ENABLE_CRYPTO */ #endif /* CRYPTO_H */ |