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| author | Matthias Schiffer <mschiffer@universe-factory.net> | 2013-11-15 05:44:02 +0100 |
|---|---|---|
| committer | Matthias Schiffer <mschiffer@universe-factory.net> | 2013-11-15 05:44:02 +0100 |
| commit | 0504f57c91eb7dd2ac4adfc6906e006f775a76e4 (patch) | |
| tree | 4de445b2525fdfd4fafe0dfa97fd266dde7efd2f /src/methods/xsalsa20_poly1305 | |
| parent | bef39b72834173e969efc6cee10145300a3af94c (diff) | |
| download | fastd-0504f57c91eb7dd2ac4adfc6906e006f775a76e4.tar fastd-0504f57c91eb7dd2ac4adfc6906e006f775a76e4.zip | |
methods/common: decrease nonce length to 6, add flags byte
Diffstat (limited to 'src/methods/xsalsa20_poly1305')
| -rw-r--r-- | src/methods/xsalsa20_poly1305/xsalsa20_poly1305.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/src/methods/xsalsa20_poly1305/xsalsa20_poly1305.c b/src/methods/xsalsa20_poly1305/xsalsa20_poly1305.c index f7709bb..01c623a 100644 --- a/src/methods/xsalsa20_poly1305/xsalsa20_poly1305.c +++ b/src/methods/xsalsa20_poly1305/xsalsa20_poly1305.c @@ -42,7 +42,7 @@ static bool method_provides(const char *name) { } static size_t method_max_packet_size(fastd_context_t *ctx) { - return (fastd_max_packet_size(ctx) + COMMON_NONCEBYTES + crypto_secretbox_xsalsa20poly1305_ZEROBYTES - crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES); + return (fastd_max_packet_size(ctx) + COMMON_HEADBYTES + crypto_secretbox_xsalsa20poly1305_ZEROBYTES - crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES); } static size_t method_min_encrypt_head_space(fastd_context_t *ctx UNUSED) { @@ -50,7 +50,7 @@ static size_t method_min_encrypt_head_space(fastd_context_t *ctx UNUSED) { } static size_t method_min_decrypt_head_space(fastd_context_t *ctx UNUSED) { - return (crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES - COMMON_NONCEBYTES); + return (crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES - COMMON_HEADBYTES); } static size_t method_min_tail_space(fastd_context_t *ctx UNUSED) { @@ -116,8 +116,9 @@ static bool method_encrypt(fastd_context_t *ctx, fastd_peer_t *peer UNUSED, fast fastd_buffer_free(in); - fastd_buffer_push_head(ctx, out, crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES-COMMON_NONCEBYTES); + fastd_buffer_push_head(ctx, out, crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES-COMMON_HEADBYTES); memcpy(out->data, session->common.send_nonce, COMMON_NONCEBYTES); + /* flags are 0, no need to set */ fastd_method_increment_nonce(&session->common); @@ -125,12 +126,15 @@ static bool method_encrypt(fastd_context_t *ctx, fastd_peer_t *peer UNUSED, fast } static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_method_session_state_t *session, fastd_buffer_t *out, fastd_buffer_t in) { - if (in.len < COMMON_NONCEBYTES) + if (in.len < COMMON_HEADBYTES) return false; if (!method_session_is_valid(ctx, session)) return false; + if (((const uint8_t*)in.data)[COMMON_NONCEBYTES]) /* flags */ + return false; + uint8_t nonce[crypto_secretbox_xsalsa20poly1305_NONCEBYTES]; memcpy(nonce, in.data, COMMON_NONCEBYTES); memset(nonce+COMMON_NONCEBYTES, 0, crypto_secretbox_xsalsa20poly1305_NONCEBYTES-COMMON_NONCEBYTES); @@ -139,7 +143,7 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho if (!fastd_method_is_nonce_valid(ctx, &session->common, nonce, &age)) return false; - fastd_buffer_pull_head(ctx, &in, crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES-COMMON_NONCEBYTES); + fastd_buffer_pull_head(ctx, &in, crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES-COMMON_HEADBYTES); memset(in.data, 0, crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES); *out = fastd_buffer_alloc(ctx, in.len, 0, 0); @@ -148,7 +152,7 @@ static bool method_decrypt(fastd_context_t *ctx, fastd_peer_t *peer, fastd_metho fastd_buffer_free(*out); /* restore input buffer */ - fastd_buffer_push_head(ctx, &in, crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES-COMMON_NONCEBYTES); + fastd_buffer_push_head(ctx, &in, crypto_secretbox_xsalsa20poly1305_BOXZEROBYTES-COMMON_HEADBYTES); memcpy(in.data, nonce, COMMON_NONCEBYTES); return false; } |