diff options
Diffstat (limited to 'src/lib/crypt_ops/crypto_format.c')
| -rw-r--r-- | src/lib/crypt_ops/crypto_format.c | 113 |
1 files changed, 67 insertions, 46 deletions
diff --git a/src/lib/crypt_ops/crypto_format.c b/src/lib/crypt_ops/crypto_format.c index 84f73e5272..4483b7d2f5 100644 --- a/src/lib/crypt_ops/crypto_format.c +++ b/src/lib/crypt_ops/crypto_format.c @@ -1,7 +1,7 @@ /* Copyright (c) 2001, Matej Pfajfar. * Copyright (c) 2001-2004, Roger Dingledine. * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. - * Copyright (c) 2007-2019, The Tor Project, Inc. */ + * Copyright (c) 2007-2020, The Tor Project, Inc. */ /* See LICENSE for licensing information */ /** @@ -104,7 +104,7 @@ crypto_read_tagged_contents_from_file(const char *fname, prefix[32] = 0; /* Check type, extract tag. */ if (strcmpstart(prefix, "== ") || strcmpend(prefix, " ==") || - ! tor_mem_is_zero(prefix+strlen(prefix), 32-strlen(prefix))) { + ! fast_mem_is_zero(prefix+strlen(prefix), 32-strlen(prefix))) { saved_errno = EINVAL; goto end; } @@ -131,20 +131,36 @@ crypto_read_tagged_contents_from_file(const char *fname, return r; } -/** Encode <b>pkey</b> as a base64-encoded string, without trailing "=" - * characters, in the buffer <b>output</b>, which must have at least - * CURVE25519_BASE64_PADDED_LEN+1 bytes available. Return 0 on success, -1 on - * failure. */ -int +/** Encode <b>pkey</b> as a base64-encoded string in the buffer <b>output</b>. + * If <b>pad</b> is false do not include trailing "=" characters, otherwise + * include them. <b>output</b> must have at least + * CURVE25519_BASE64_PADDED_LEN+1 bytes available, even if <b>pad</b> is false. + * Can not fail. + * + * Careful! CURVE25519_BASE64_PADDED_LEN is one byte longer than + * ED25519_BASE64_LEN. + */ +void curve25519_public_to_base64(char *output, - const curve25519_public_key_t *pkey) + const curve25519_public_key_t *pkey, bool pad) { - char buf[128]; - base64_encode(buf, sizeof(buf), - (const char*)pkey->public_key, CURVE25519_PUBKEY_LEN, 0); - buf[CURVE25519_BASE64_PADDED_LEN] = '\0'; - memcpy(output, buf, CURVE25519_BASE64_PADDED_LEN+1); - return 0; + int n, expected_len; + if (pad) { + n = base64_encode(output, CURVE25519_BASE64_PADDED_LEN+1, + (const char*)pkey->public_key, + CURVE25519_PUBKEY_LEN, 0); + expected_len = CURVE25519_BASE64_PADDED_LEN; + } else { + n = base64_encode_nopad(output, CURVE25519_BASE64_PADDED_LEN+1, + (const uint8_t*)pkey->public_key, + CURVE25519_PUBKEY_LEN); + expected_len = CURVE25519_BASE64_LEN; + } + + /* These asserts should always succeed, unless there is a bug in + * base64_encode(). */ + tor_assert(n == expected_len); + tor_assert(output[expected_len] == '\0'); } /** Try to decode a base64-encoded curve25519 public key from <b>input</b> @@ -155,11 +171,11 @@ curve25519_public_from_base64(curve25519_public_key_t *pkey, const char *input) { size_t len = strlen(input); - if (len == CURVE25519_BASE64_PADDED_LEN - 1) { + if (len == CURVE25519_BASE64_LEN) { /* not padded */ return digest256_from_base64((char*)pkey->public_key, input); } else if (len == CURVE25519_BASE64_PADDED_LEN) { - char buf[128]; + char buf[CURVE25519_BASE64_PADDED_LEN+1]; if (base64_decode(buf, sizeof(buf), input, len) != CURVE25519_PUBKEY_LEN) return -1; memcpy(pkey->public_key, buf, CURVE25519_PUBKEY_LEN); @@ -181,8 +197,7 @@ ed25519_fmt(const ed25519_public_key_t *pkey) if (ed25519_public_key_is_zero(pkey)) { strlcpy(formatted, "<unset>", sizeof(formatted)); } else { - int r = ed25519_public_to_base64(formatted, pkey); - tor_assert(!r); + ed25519_public_to_base64(formatted, pkey); } } else { strlcpy(formatted, "<null>", sizeof(formatted)); @@ -202,28 +217,35 @@ ed25519_public_from_base64(ed25519_public_key_t *pkey, /** Encode the public key <b>pkey</b> into the buffer at <b>output</b>, * which must have space for ED25519_BASE64_LEN bytes of encoded key, - * plus one byte for a terminating NUL. Return 0 on success, -1 on failure. + * plus one byte for a terminating NUL. + * Can not fail. + * + * Careful! ED25519_BASE64_LEN is one byte shorter than + * CURVE25519_BASE64_PADDED_LEN. */ -int +void ed25519_public_to_base64(char *output, const ed25519_public_key_t *pkey) { - return digest256_to_base64(output, (const char *)pkey->pubkey); + digest256_to_base64(output, (const char *)pkey->pubkey); } /** Encode the signature <b>sig</b> into the buffer at <b>output</b>, * which must have space for ED25519_SIG_BASE64_LEN bytes of encoded signature, - * plus one byte for a terminating NUL. Return 0 on success, -1 on failure. + * plus one byte for a terminating NUL. + * Can not fail. */ -int +void ed25519_signature_to_base64(char *output, const ed25519_signature_t *sig) { char buf[256]; int n = base64_encode_nopad(buf, sizeof(buf), sig->sig, ED25519_SIG_LEN); + /* These asserts should always succeed, unless there is a bug in + * base64_encode_nopad(). */ tor_assert(n == ED25519_SIG_BASE64_LEN); + tor_assert(buf[ED25519_SIG_BASE64_LEN] == '\0'); memcpy(output, buf, ED25519_SIG_BASE64_LEN+1); - return 0; } /** Try to decode the string <b>input</b> into an ed25519 signature. On @@ -233,16 +255,11 @@ int ed25519_signature_from_base64(ed25519_signature_t *sig, const char *input) { - if (strlen(input) != ED25519_SIG_BASE64_LEN) return -1; - char buf[ED25519_SIG_BASE64_LEN+3]; - memcpy(buf, input, ED25519_SIG_BASE64_LEN); - buf[ED25519_SIG_BASE64_LEN+0] = '='; - buf[ED25519_SIG_BASE64_LEN+1] = '='; - buf[ED25519_SIG_BASE64_LEN+2] = 0; char decoded[128]; - int n = base64_decode(decoded, sizeof(decoded), buf, strlen(buf)); + int n = base64_decode(decoded, sizeof(decoded), input, + ED25519_SIG_BASE64_LEN); if (n < 0 || n != ED25519_SIG_LEN) return -1; memcpy(sig->sig, decoded, ED25519_SIG_LEN); @@ -250,24 +267,26 @@ ed25519_signature_from_base64(ed25519_signature_t *sig, return 0; } -/** Base64 encode DIGEST_LINE bytes from <b>digest</b>, remove the trailing = +/** Base64 encode DIGEST_LEN bytes from <b>digest</b>, remove the trailing = * characters, and store the nul-terminated result in the first - * BASE64_DIGEST_LEN+1 bytes of <b>d64</b>. */ -/* XXXX unify with crypto_format.c code */ -int + * BASE64_DIGEST_LEN+1 bytes of <b>d64</b>. + * Can not fail. */ +void digest_to_base64(char *d64, const char *digest) { char buf[256]; - base64_encode(buf, sizeof(buf), digest, DIGEST_LEN, 0); - buf[BASE64_DIGEST_LEN] = '\0'; + int n = base64_encode_nopad(buf, sizeof(buf), + (const uint8_t *)digest, DIGEST_LEN); + /* These asserts should always succeed, unless there is a bug in + * base64_encode_nopad(). */ + tor_assert(n == BASE64_DIGEST_LEN); + tor_assert(buf[BASE64_DIGEST_LEN] == '\0'); memcpy(d64, buf, BASE64_DIGEST_LEN+1); - return 0; } /** Given a base64 encoded, nul-terminated digest in <b>d64</b> (without * trailing newline or = characters), decode it and store the result in the * first DIGEST_LEN bytes at <b>digest</b>. */ -/* XXXX unify with crypto_format.c code */ int digest_from_base64(char *digest, const char *d64) { @@ -279,22 +298,24 @@ digest_from_base64(char *digest, const char *d64) /** Base64 encode DIGEST256_LINE bytes from <b>digest</b>, remove the * trailing = characters, and store the nul-terminated result in the first - * BASE64_DIGEST256_LEN+1 bytes of <b>d64</b>. */ - /* XXXX unify with crypto_format.c code */ -int + * BASE64_DIGEST256_LEN+1 bytes of <b>d64</b>. + * Can not fail. */ +void digest256_to_base64(char *d64, const char *digest) { char buf[256]; - base64_encode(buf, sizeof(buf), digest, DIGEST256_LEN, 0); - buf[BASE64_DIGEST256_LEN] = '\0'; + int n = base64_encode_nopad(buf, sizeof(buf), + (const uint8_t *)digest, DIGEST256_LEN); + /* These asserts should always succeed, unless there is a bug in + * base64_encode_nopad(). */ + tor_assert(n == BASE64_DIGEST256_LEN); + tor_assert(buf[BASE64_DIGEST256_LEN] == '\0'); memcpy(d64, buf, BASE64_DIGEST256_LEN+1); - return 0; } /** Given a base64 encoded, nul-terminated digest in <b>d64</b> (without * trailing newline or = characters), decode it and store the result in the * first DIGEST256_LEN bytes at <b>digest</b>. */ -/* XXXX unify with crypto_format.c code */ int digest256_from_base64(char *digest, const char *d64) { |