| Message ID | 1844221604326075@mail.yandex.com |
|---|---|
| State | Accepted |
| Commit | 03fb314acfa4f5a4af84a6fc82a425477fd352eb |
| Headers | show |
| Series | [FFmpeg-devel,v4] Add support for playing Audible AAXC (.aaxc) files | expand |
| Context | Check | Description |
|---|---|---|
| andriy/x86_make | success | Make finished |
| andriy/x86_make_fate | success | Make fate finished |
| andriy/PPC64_make | success | Make finished |
| andriy/PPC64_make_fate | success | Make fate finished |
Next time apply without [PATCH v4] in main log On Mon, Nov 2, 2020 at 3:19 PM Vesselin Bontchev < vesselin.bontchev@yandex.com> wrote: > The AAXC container format is the same as the (already supported) Audible > AAX format but it uses a different encryption scheme. > > Note: audible_key and audible_iv values are variable (per file) and are > externally fed. > > It is possible to extend https://github.com/mkb79/Audible to derive the > audible_key and audible_key values. > > Relevant code: > > def decrypt_voucher(deviceSerialNumber, customerId, deviceType, asin, > voucher): > buf = (deviceType + deviceSerialNumber + customerId + > asin).encode("ascii") > digest = hashlib.sha256(buf).digest() > key = digest[0:16] > iv = digest[16:] > > # decrypt "voucher" using AES in CBC mode with no padding > cipher = AES.new(key, AES.MODE_CBC, iv) > plaintext = cipher.decrypt(voucher).rstrip(b"\x00") # improve this! > return json.loads(plaintext) > > The decrypted "voucher" has the required audible_key and audible_iv > values. > > Update (Nov-2020): This patch has now been tested by multiple folks - > details at the following URL: > > https://github.com/mkb79/Audible/issues/3 > > Signed-off-by: Vesselin Bontchev <vesselin.bontchev@yandex.com> > > ... > > Thanks Carl for all the reviews. Hopefully we can merge this patch soon :) > > Vesselin > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
diff --git a/libavformat/isom.h b/libavformat/isom.h index 78495fd336..5a6d504090 100644 --- a/libavformat/isom.h +++ b/libavformat/isom.h @@ -286,6 +286,10 @@ typedef struct MOVContext { int activation_bytes_size; void *audible_fixed_key; int audible_fixed_key_size; + void *audible_key; + int audible_key_size; + void *audible_iv; + int audible_iv_size; struct AVAES *aes_decrypt; uint8_t *decryption_key; int decryption_key_len; diff --git a/libavformat/mov.c b/libavformat/mov.c index dd0db6bca7..2b90e31170 100644 --- a/libavformat/mov.c +++ b/libavformat/mov.c @@ -1075,6 +1075,30 @@ fail: return ret; } +static int mov_aaxc_crypto(MOVContext *c) +{ + if (c->audible_key_size != 16) { + av_log(c->fc, AV_LOG_FATAL, "[aaxc] audible_key value needs to be 16 bytes!\n"); + return AVERROR(EINVAL); + } + + if (c->audible_iv_size != 16) { + av_log(c->fc, AV_LOG_FATAL, "[aaxc] audible_iv value needs to be 16 bytes!\n"); + return AVERROR(EINVAL); + } + + c->aes_decrypt = av_aes_alloc(); + if (!c->aes_decrypt) { + return AVERROR(ENOMEM); + } + + memcpy(c->file_key, c->audible_key, 16); + memcpy(c->file_iv, c->audible_iv, 16); + c->aax_mode = 1; + + return 0; +} + // Audible AAX (and AAX+) bytestream decryption static int aax_filter(uint8_t *input, int size, MOVContext *c) { @@ -1123,6 +1147,11 @@ static int mov_read_ftyp(MOVContext *c, AVIOContext *pb, MOVAtom atom) av_dict_set(&c->fc->metadata, "compatible_brands", comp_brands_str, AV_DICT_DONT_STRDUP_VAL); + // Logic for handling Audible's .aaxc files + if (!strcmp(type, "aaxc")) { + mov_aaxc_crypto(c); + } + return 0; } @@ -8170,6 +8199,10 @@ static const AVOption mov_options[] = { AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, .flags = FLAGS }, { "activation_bytes", "Secret bytes for Audible AAX files", OFFSET(activation_bytes), AV_OPT_TYPE_BINARY, .flags = AV_OPT_FLAG_DECODING_PARAM }, + { "audible_key", "AES-128 Key for Audible AAXC files", OFFSET(audible_key), + AV_OPT_TYPE_BINARY, .flags = AV_OPT_FLAG_DECODING_PARAM }, + { "audible_iv", "AES-128 IV for Audible AAXC files", OFFSET(audible_iv), + AV_OPT_TYPE_BINARY, .flags = AV_OPT_FLAG_DECODING_PARAM }, { "audible_fixed_key", // extracted from libAAX_SDK.so and AAXSDKWin.dll files! "Fixed key used for handling Audible AAX files", OFFSET(audible_fixed_key), AV_OPT_TYPE_BINARY, {.str="77214d4b196a87cd520045fd20a51d67"},
The AAXC container format is the same as the (already supported) Audible AAX format but it uses a different encryption scheme. Note: audible_key and audible_iv values are variable (per file) and are externally fed. It is possible to extend https://github.com/mkb79/Audible to derive the audible_key and audible_key values. Relevant code: def decrypt_voucher(deviceSerialNumber, customerId, deviceType, asin, voucher): buf = (deviceType + deviceSerialNumber + customerId + asin).encode("ascii") digest = hashlib.sha256(buf).digest() key = digest[0:16] iv = digest[16:] # decrypt "voucher" using AES in CBC mode with no padding cipher = AES.new(key, AES.MODE_CBC, iv) plaintext = cipher.decrypt(voucher).rstrip(b"\x00") # improve this! return json.loads(plaintext) The decrypted "voucher" has the required audible_key and audible_iv values. Update (Nov-2020): This patch has now been tested by multiple folks - details at the following URL: https://github.com/mkb79/Audible/issues/3 Signed-off-by: Vesselin Bontchev <vesselin.bontchev@yandex.com> ... Thanks Carl for all the reviews. Hopefully we can merge this patch soon :) Vesselin Subject: [PATCH] [v4] Add support for playing Audible AAXC (.aaxc) files The AAXC container format is the same as the (already supported) Audible AAX format but it uses a different encryption scheme. Note: audible_key and audible_iv values are variable (per file) and are externally fed. It is possible to extend https://github.com/mkb79/Audible to derive the audible_key and audible_key values. Relevant code: def decrypt_voucher(deviceSerialNumber, customerId, deviceType, asin, voucher): buf = (deviceType + deviceSerialNumber + customerId + asin).encode("ascii") digest = hashlib.sha256(buf).digest() key = digest[0:16] iv = digest[16:] # decrypt "voucher" using AES in CBC mode with no padding cipher = AES.new(key, AES.MODE_CBC, iv) plaintext = cipher.decrypt(voucher).rstrip(b"\x00") # improve this! return json.loads(plaintext) The decrypted "voucher" has the required audible_key and audible_iv values. Update (Nov-2020): This patch has now been tested by multiple folks - details at the following URL: https://github.com/mkb79/Audible/issues/3 Signed-off-by: Vesselin Bontchev <vesselin.bontchev@yandex.com> --- libavformat/isom.h | 4 ++++ libavformat/mov.c | 33 +++++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+)