diff options
| -rw-r--r-- | g10/cipher-aead.c | 81 | ||||
| -rw-r--r-- | g10/decrypt-data.c | 16 |
2 files changed, 55 insertions, 42 deletions
diff --git a/g10/cipher-aead.c b/g10/cipher-aead.c index 1457baaa5..f9a996c80 100644 --- a/g10/cipher-aead.c +++ b/g10/cipher-aead.c @@ -200,9 +200,6 @@ write_header (cipher_filter_context_t *cfx, iobuf_t a) if (err) return err; - err = set_nonce_and_ad (cfx, 0); - if (err) - return err; cfx->wrote_header = 1; leave: @@ -238,9 +235,6 @@ write_final_chunk (cipher_filter_context_t *cfx, iobuf_t a) gpg_error_t err; char dummy[1]; - if (cfx->chunklen) - cfx->chunkindex++; - err = set_nonce_and_ad (cfx, 1); if (err) goto leave; @@ -297,8 +291,18 @@ do_flush (cipher_filter_context_t *cfx, iobuf_t a, byte *buf, size_t size) if (cfx->buflen == cfx->bufsize || finalize) { if (DBG_FILTER) - log_debug ("encrypting: buflen=%zu %s n=%zu\n", - cfx->buflen, finalize?"(finalize)":"", n); + log_debug ("encrypting: size=%zu buflen=%zu %s n=%zu\n", + size, cfx->buflen, finalize?"(finalize)":"", n); + + if (!cfx->chunklen) + { + if (DBG_FILTER) + log_debug ("start encrypting a new chunk\n"); + err = set_nonce_and_ad (cfx, 0); + if (err) + goto leave; + } + if (finalize) gcry_cipher_final (cfx->cipher_hd); if (DBG_FILTER) @@ -314,8 +318,10 @@ do_flush (cipher_filter_context_t *cfx, iobuf_t a, byte *buf, size_t size) * be called after gcry_cipher_final and before * gcry_cipher_gettag - at least with libgcrypt 1.8 and OCB * mode. */ - gcry_cipher_encrypt (cfx->cipher_hd, cfx->buffer, cfx->buflen, - NULL, 0); + err = gcry_cipher_encrypt (cfx->cipher_hd, cfx->buffer, cfx->buflen, + NULL, 0); + if (err) + goto leave; if (finalize && DBG_FILTER) log_printhex (cfx->buffer, cfx->buflen, "ciphr(1):"); err = my_iobuf_write (a, cfx->buffer, cfx->buflen); @@ -328,19 +334,14 @@ do_flush (cipher_filter_context_t *cfx, iobuf_t a, byte *buf, size_t size) if (finalize) { if (DBG_FILTER) - log_debug ("chunklen=%ju total=%ju\n", + log_debug ("writing tag: chunklen=%ju total=%ju\n", (uintmax_t)cfx->chunklen, (uintmax_t)cfx->total); err = write_auth_tag (cfx, a); if (err) goto leave; - if (DBG_FILTER) - log_debug ("starting a new chunk (cur size=%zu)\n", size); cfx->chunkindex++; cfx->chunklen = 0; - err = set_nonce_and_ad (cfx, 0); - if (err) - goto leave; finalize = 0; } } @@ -361,38 +362,42 @@ do_free (cipher_filter_context_t *cfx, iobuf_t a) if (DBG_FILTER) log_debug ("do_free: buflen=%zu\n", cfx->buflen); - /* FIXME: Check what happens if we just wrote the last chunk and no - * more bytes were to encrypt. We should then not call finalize and - * write the auth tag again, right? May this at all happen? */ - - /* Call finalize which will also allow us to flush out and encrypt - * the last arbitrary length buffer. */ - gcry_cipher_final (cfx->cipher_hd); - - /* Encrypt any remaining bytes. */ if (cfx->buflen) { if (DBG_FILTER) - log_debug ("processing last %zu bytes of the last chunk\n", - cfx->buflen); - gcry_cipher_encrypt (cfx->cipher_hd, cfx->buffer, cfx->buflen, NULL, 0); + log_debug ("encrypting last %zu bytes of the last chunk\n",cfx->buflen); + + if (!cfx->chunklen) + { + if (DBG_FILTER) + log_debug ("start encrypting a new chunk\n"); + err = set_nonce_and_ad (cfx, 0); + if (err) + goto leave; + } + + gcry_cipher_final (cfx->cipher_hd); + err = gcry_cipher_encrypt (cfx->cipher_hd, cfx->buffer, cfx->buflen, + NULL, 0); + if (err) + goto leave; err = my_iobuf_write (a, cfx->buffer, cfx->buflen); if (err) goto leave; /* log_printhex (cfx->buffer, cfx->buflen, "wrote:"); */ cfx->chunklen += cfx->buflen; cfx->total += cfx->buflen; - } - else /* Dummy encryption. */ - gcry_cipher_encrypt (cfx->cipher_hd, cfx->buffer, 0, NULL, 0); - /* Get and write the authentication tag. */ - if (DBG_FILTER) - log_debug ("chunklen=%ju total=%ju\n", - (uintmax_t)cfx->chunklen, (uintmax_t)cfx->total); - err = write_auth_tag (cfx, a); - if (err) - goto leave; + /* Get and write the authentication tag. */ + if (DBG_FILTER) + log_debug ("writing tag: chunklen=%ju total=%ju\n", + (uintmax_t)cfx->chunklen, (uintmax_t)cfx->total); + err = write_auth_tag (cfx, a); + if (err) + goto leave; + cfx->chunkindex++; + cfx->chunklen = 0; + } /* Write the final chunk. */ if (DBG_FILTER) diff --git a/g10/decrypt-data.c b/g10/decrypt-data.c index 5594d9055..a3151b5ed 100644 --- a/g10/decrypt-data.c +++ b/g10/decrypt-data.c @@ -770,17 +770,25 @@ aead_underflow (decode_filter_ctx_t dfx, iobuf_t a, byte *buf, size_t *ret_len) if (dfx->eof_seen) { - if (DBG_FILTER) - log_debug ("eof seen: holdback buffer has the last and final tag\n"); - log_assert (dfx->holdbacklen >= 32); if (dfx->chunklen) { + if (DBG_FILTER) + log_debug ("eof seen: holdback has the last and final tag\n"); + log_assert (dfx->holdbacklen >= 32); err = aead_checktag (dfx, 0, dfx->holdback); if (err) goto leave; dfx->chunklen = 0; dfx->chunkindex++; + off = 16; + } + else + { + if (DBG_FILTER) + log_debug ("eof seen: holdback has the final tag\n"); + log_assert (dfx->holdbacklen >= 16); + off = 0; } /* Check the final chunk. */ @@ -796,7 +804,7 @@ aead_underflow (decode_filter_ctx_t dfx, iobuf_t a, byte *buf, size_t *ret_len) gpg_strerror (err)); goto leave; } - err = aead_checktag (dfx, 1, dfx->holdback+16); + err = aead_checktag (dfx, 1, dfx->holdback+off); if (err) goto leave; err = gpg_error (GPG_ERR_EOF); |