diff options
Diffstat (limited to 'epan/dissectors/packet-hdcp2.c')
| -rw-r--r-- | epan/dissectors/packet-hdcp2.c | 411 |
1 files changed, 411 insertions, 0 deletions
diff --git a/epan/dissectors/packet-hdcp2.c b/epan/dissectors/packet-hdcp2.c new file mode 100644 index 00000000..2905a26b --- /dev/null +++ b/epan/dissectors/packet-hdcp2.c @@ -0,0 +1,411 @@ +/* packet-hdcp2.c + * Routines for HDCP2 dissection + * Copyright 2011-2012, Martin Kaiser <martin@kaiser.cx> + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 Gerald Combs + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +/* + * This dissector supports HDCP 2.x over TCP. For now, only the + * authentication protocol messages are supported. + * + * The specification of version 2 of the protocol can be found at + * http://www.digital-cp.com/files/static_page_files/DABB540C-1A4B-B294-D0008CB2D348FA19/HDCP Interface Independent Adaptation Specification Rev2_1.pdf + */ + +#include "config.h" + +#include <epan/packet.h> +#include <epan/prefs.h> +#include <epan/ptvcursor.h> +#include <epan/expert.h> + +void proto_register_hdcp2(void); +void proto_reg_handoff_hdcp2(void); + +static int proto_hdcp2 = -1; + +static gint ett_hdcp2 = -1; +static gint ett_hdcp2_cert = -1; + +static int hf_hdcp2_msg_id = -1; +static int hf_hdcp2_r_tx = -1; +static int hf_hdcp2_repeater = -1; +static int hf_hdcp2_cert_rcv_id = -1; +static int hf_hdcp2_cert_n = -1; +static int hf_hdcp2_cert_e = -1; +static int hf_hdcp2_cert_rcv_sig = -1; +static int hf_hdcp2_e_kpub_km = -1; +static int hf_hdcp2_e_kh_km = -1; +static int hf_hdcp2_m = -1; +static int hf_hdcp2_r_rx = -1; +static int hf_hdcp2_h_prime = -1; +static int hf_hdcp2_r_n = -1; +static int hf_hdcp2_l_prime = -1; +static int hf_hdcp2_e_dkey_ks = -1; +static int hf_hdcp2_r_iv = -1; +static int hf_hdcp2_reserved = -1; +static int hf_hdcp2_tx_length = -1; +static int hf_hdcp2_tx_version = -1; +static int hf_hdcp2_tx_loc_precompute = -1; +static int hf_hdcp2_rx_length = -1; +static int hf_hdcp2_rx_version = -1; +static int hf_hdcp2_rx_loc_precompute = -1; + +static expert_field ei_hdcp2_reserved_0 = EI_INIT; +static expert_field ei_hdcp2_version_not_2 = EI_INIT; +static expert_field ei_hdcp2_length = EI_INIT; + + +#define ID_AKE_INIT 2 +#define ID_AKE_SEND_CERT 3 +#define ID_AKE_NO_STORED_KM 4 +#define ID_AKE_STORED_KM 5 +#define ID_AKE_SEND_RRX 6 +#define ID_AKE_SEND_H_PRIME 7 +#define ID_AKE_SEND_PAIRING_INFO 8 +#define ID_LC_INIT 9 +#define ID_LC_SEND_L_PRIME 10 +#define ID_SKE_SEND_EKS 11 +#define ID_AKE_TRANSMITTER_INFO 19 +#define ID_AKE_RECEIVER_INFO 20 +#define ID_MAX 31 + +#define RCV_ID_LEN 5 /* all lengths are in bytes */ +#define N_LEN 128 +#define E_LEN 3 +#define RCV_SIG_LEN 384 + +#define MSG_FIELD_TRANSMITTER_INFO_LENGTH 6 +#define MSG_FIELD_RECEIVER_INFO_LENGTH 6 + +#define CERT_RX_LEN (RCV_ID_LEN + N_LEN + E_LEN + 2 + RCV_SIG_LEN) + +static const value_string hdcp2_msg_id[] = { + { ID_AKE_INIT, "AKE_Init" }, + { ID_AKE_TRANSMITTER_INFO, "AKE_Transmitter_Info" }, + { ID_AKE_SEND_CERT, "AKE_Send_Cert" }, + { ID_AKE_RECEIVER_INFO, "AKE_Receiver_Info" }, + { ID_AKE_NO_STORED_KM, "AKE_No_Stored_km" }, + { ID_AKE_STORED_KM, "AKE_Stored_km" }, + { ID_AKE_SEND_RRX, "AKE_Send_rrx" }, + { ID_AKE_SEND_H_PRIME, "AKE_Send_H_prime" }, + { ID_AKE_SEND_PAIRING_INFO, "AKE_Send_Pairing_Info" }, + { ID_LC_INIT, "LC_Init" }, + { ID_LC_SEND_L_PRIME, "LC_Send_L_prime" }, + { ID_SKE_SEND_EKS, "SKE_Send_Eks" }, + { 0, NULL } +}; + +typedef struct _msg_info_t { + guint8 id; + guint16 len; /* number of bytes following initial msg_id field */ +} msg_info_t; + +static wmem_map_t *msg_table = NULL; + +static const msg_info_t msg_info[] = { + { ID_AKE_INIT, 8 }, + { ID_AKE_TRANSMITTER_INFO, 5 }, + { ID_AKE_SEND_CERT, 1+CERT_RX_LEN }, + { ID_AKE_RECEIVER_INFO, 5 }, + { ID_AKE_NO_STORED_KM, 128 }, + { ID_AKE_STORED_KM, 32 }, + { ID_AKE_SEND_RRX, 8 }, + { ID_AKE_SEND_H_PRIME, 32 }, + { ID_AKE_SEND_PAIRING_INFO, 16 }, + { ID_LC_INIT, 8 }, + { ID_LC_SEND_L_PRIME, 32 }, + { ID_SKE_SEND_EKS, 24 } +}; + + +static int +dissect_hdcp2(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void *data _U_) +{ + msg_info_t *mi; + proto_item *pi; + proto_tree *hdcp_tree, *cert_tree; + guint8 msg_id, version; + gboolean repeater, loc_precomp; + guint16 reserved, length; + ptvcursor_t *cursor; + + /* do the plausibility checks before setting up anything */ + + /* make sure that tvb_get_guint8() won't throw an exception */ + if (tvb_captured_length(tvb) < 1) + return 0; + msg_id = tvb_get_guint8(tvb, 0); + if (msg_id > ID_MAX) + return 0; + + mi = (msg_info_t *)wmem_map_lookup(msg_table, + GUINT_TO_POINTER((guint)msg_id)); + /* 1 -> start after msg_id byte */ + if (!mi || mi->len!=tvb_reported_length_remaining(tvb, 1)) + return 0; + + col_set_str(pinfo->cinfo, COL_PROTOCOL, "HDCP2"); + col_clear(pinfo->cinfo, COL_INFO); + + pi = proto_tree_add_protocol_format(tree, proto_hdcp2, + tvb, 0, tvb_reported_length(tvb), "HDCP2"); + hdcp_tree = proto_item_add_subtree(pi, ett_hdcp2); + cursor = ptvcursor_new(pinfo->pool, hdcp_tree, tvb, 0); + + col_append_str(pinfo->cinfo, COL_INFO, + val_to_str(msg_id, hdcp2_msg_id, "unknown (0x%x)")); + ptvcursor_add(cursor, hf_hdcp2_msg_id, 1, ENC_BIG_ENDIAN); + + switch (msg_id) { + case ID_AKE_INIT: + ptvcursor_add(cursor, hf_hdcp2_r_tx, 8, ENC_BIG_ENDIAN); + break; + case ID_AKE_TRANSMITTER_INFO: + length = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor)); + pi = proto_tree_add_item(ptvcursor_tree(cursor), + hf_hdcp2_tx_length, tvb, ptvcursor_current_offset(cursor), + 2, ENC_BIG_ENDIAN); + if (length < MSG_FIELD_TRANSMITTER_INFO_LENGTH) { + expert_add_info_format(pinfo, pi, &ei_hdcp2_length, + "Length must be at least %d", + MSG_FIELD_TRANSMITTER_INFO_LENGTH); + } + ptvcursor_advance(cursor, 2); + version = tvb_get_guint8(tvb, ptvcursor_current_offset(cursor)); + pi = proto_tree_add_item(ptvcursor_tree(cursor), + hf_hdcp2_tx_version, tvb, ptvcursor_current_offset(cursor), + 1, ENC_BIG_ENDIAN); + if (version != 2) { + expert_add_info(pinfo, pi, &ei_hdcp2_version_not_2); + } + ptvcursor_advance(cursor, 1); + loc_precomp = ((tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor)) + & 0x01) == 0x01); + col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, + loc_precomp ? "locality precompute" : "no locality precompute"); + ptvcursor_add(cursor, hf_hdcp2_tx_loc_precompute, 2, ENC_BIG_ENDIAN); + break; + case ID_AKE_SEND_CERT: + repeater = ((tvb_get_guint8(tvb, ptvcursor_current_offset(cursor)) + & 0x01) == 0x01); + col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, + repeater ? "repeater" : "no repeater"); + ptvcursor_add(cursor, hf_hdcp2_repeater, 1, ENC_BIG_ENDIAN); + cert_tree = ptvcursor_add_text_with_subtree(cursor, CERT_RX_LEN, + ett_hdcp2_cert, "%s", "HDCP2 Certificate"); + ptvcursor_add(cursor, hf_hdcp2_cert_rcv_id, RCV_ID_LEN, ENC_NA); + ptvcursor_add(cursor, hf_hdcp2_cert_n, N_LEN, ENC_NA); + ptvcursor_add(cursor, hf_hdcp2_cert_e, E_LEN, ENC_BIG_ENDIAN); + reserved = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor)); + pi = proto_tree_add_item(cert_tree, hf_hdcp2_reserved, tvb, + ptvcursor_current_offset(cursor), 2, ENC_BIG_ENDIAN); + if ((reserved & 0xEFFF) != 0) { + expert_add_info(pinfo, pi, &ei_hdcp2_reserved_0); + } + ptvcursor_advance(cursor, 2); + ptvcursor_add(cursor, hf_hdcp2_cert_rcv_sig, RCV_SIG_LEN, ENC_NA); + ptvcursor_pop_subtree(cursor); + break; + case ID_AKE_RECEIVER_INFO: + length = tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor)); + pi = proto_tree_add_item(ptvcursor_tree(cursor), + hf_hdcp2_rx_length, tvb, ptvcursor_current_offset(cursor), + 2, ENC_BIG_ENDIAN); + if (length < MSG_FIELD_RECEIVER_INFO_LENGTH) { + expert_add_info_format(pinfo, pi, &ei_hdcp2_length, + "Length must be at least %d", + MSG_FIELD_RECEIVER_INFO_LENGTH); + } + ptvcursor_advance(cursor, 2); + version = tvb_get_guint8(tvb, ptvcursor_current_offset(cursor)); + pi = proto_tree_add_item(ptvcursor_tree(cursor), + hf_hdcp2_rx_version, tvb, ptvcursor_current_offset(cursor), + 1, ENC_BIG_ENDIAN); + if (version != 2) { + expert_add_info(pinfo, pi, &ei_hdcp2_version_not_2); + } + ptvcursor_advance(cursor, 1); + loc_precomp = ((tvb_get_ntohs(tvb, ptvcursor_current_offset(cursor)) + & 0x01) == 0x01); + col_append_sep_str(pinfo->cinfo, COL_INFO, NULL, + loc_precomp ? "locality precompute" : "no locality precompute"); + ptvcursor_add(cursor, hf_hdcp2_rx_loc_precompute, 2, ENC_BIG_ENDIAN); + break; + case ID_AKE_NO_STORED_KM: + ptvcursor_add(cursor, hf_hdcp2_e_kpub_km, 128, ENC_NA); + break; + case ID_AKE_STORED_KM: + ptvcursor_add(cursor, hf_hdcp2_e_kh_km, 16, ENC_NA); + ptvcursor_add(cursor, hf_hdcp2_m, 16, ENC_NA); + break; + case ID_AKE_SEND_RRX: + ptvcursor_add(cursor, hf_hdcp2_r_rx, 8, ENC_BIG_ENDIAN); + break; + case ID_AKE_SEND_H_PRIME: + ptvcursor_add(cursor, hf_hdcp2_h_prime, 32, ENC_NA); + break; + case ID_AKE_SEND_PAIRING_INFO: + ptvcursor_add(cursor, hf_hdcp2_e_kh_km, 16, ENC_NA); + break; + case ID_LC_INIT: + ptvcursor_add(cursor, hf_hdcp2_r_n, 8, ENC_BIG_ENDIAN); + break; + case ID_LC_SEND_L_PRIME: + ptvcursor_add(cursor, hf_hdcp2_l_prime, 32, ENC_NA); + break; + case ID_SKE_SEND_EKS: + ptvcursor_add(cursor, hf_hdcp2_e_dkey_ks, 16, ENC_NA); + ptvcursor_add(cursor, hf_hdcp2_r_iv, 8, ENC_BIG_ENDIAN); + break; + default: + break; + } + + ptvcursor_free(cursor); + return tvb_reported_length(tvb); +} + + + +void +proto_register_hdcp2(void) +{ + guint i; + + static hf_register_info hf[] = { + { &hf_hdcp2_msg_id, + { "Message ID", "hdcp2.msg_id", FT_UINT8, BASE_HEX, + VALS(hdcp2_msg_id), 0, NULL, HFILL } }, + { &hf_hdcp2_r_tx, + { "r_tx", "hdcp2.r_tx", FT_UINT64, BASE_HEX, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_repeater, + { "Repeater", "hdcp2.repeater", FT_BOOLEAN, 8, + NULL, 0x1, NULL, HFILL } }, + { &hf_hdcp2_cert_rcv_id, + { "Receiver ID", "hdcp2.cert.rcv_id", FT_BYTES, BASE_NONE, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_cert_n, + { "Receiver RSA key n", "hdcp2.cert.n", FT_BYTES, BASE_NONE, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_cert_e, + { "Receiver RSA key e", "hdcp2.cert.e", FT_UINT24, BASE_HEX, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_cert_rcv_sig, + { "Receiver signature", "hdcp2.cert.rcv_sig", FT_BYTES, + BASE_NONE, NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_e_kpub_km, + { "E_kpub_km", "hdcp2.e_kpub_km", FT_BYTES, BASE_NONE, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_e_kh_km, + { "E_kh_km", "hdcp2.e_kh_km", FT_BYTES, BASE_NONE, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_m, + { "m", "hdcp2.m", FT_BYTES, BASE_NONE, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_r_rx, + { "r_rx", "hdcp2.r_rx", FT_UINT64, BASE_HEX, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_h_prime, + { "H'", "hdcp2.h_prime", FT_BYTES, BASE_NONE, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_r_n, + { "r_n", "hdcp2.r_n", FT_UINT64, BASE_HEX, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_l_prime, + { "L'", "hdcp2.l_prime", FT_BYTES, BASE_NONE, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_e_dkey_ks, + { "E_dkey_ks", "hdcp2.e_dkey_ks", FT_BYTES, BASE_NONE, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_r_iv, + { "r_iv", "hdcp2.r_iv", FT_UINT64, BASE_HEX, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_reserved, + { "Reserved", "hdcp2.reserved", FT_UINT16, BASE_HEX, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_tx_length, + { "LENGTH", "hdcp2.txinf_len", FT_UINT16, BASE_DEC, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_tx_version, + { "VERSION", "hdcp2.txinf_ver", FT_UINT8, BASE_DEC, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_tx_loc_precompute, + { "Locality Precompute", "hdcp2.txinf_cap", FT_BOOLEAN, 16, + NULL, 0x0001, NULL, HFILL } }, + { &hf_hdcp2_rx_length, + { "LENGTH", "hdcp2.rxinf_len", FT_UINT16, BASE_DEC, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_rx_version, + { "VERSION", "hdcp2.rxinf_ver", FT_UINT8, BASE_DEC, + NULL, 0, NULL, HFILL } }, + { &hf_hdcp2_rx_loc_precompute, + { "Locality Precompute", "hdcp2.rxinf_cap", FT_BOOLEAN, 16, + NULL, 0x0001, NULL, HFILL } }, + +}; + + static gint *ett[] = { + &ett_hdcp2, + &ett_hdcp2_cert, + }; + + static ei_register_info ei[] = { + { &ei_hdcp2_reserved_0, { "hdcp2.reserved.not0", PI_PROTOCOL, PI_WARN, "reserved bytes must be set to 0x0", EXPFILL }}, + { &ei_hdcp2_version_not_2, { "hdcp2.version.not2", PI_PROTOCOL, PI_WARN, "version must be set to 0x2", EXPFILL }}, + { &ei_hdcp2_length, { "hdcp2.length.invalid", PI_PROTOCOL, PI_WARN, "Invalid length", EXPFILL }}, + }; + + module_t *hdcp2_module; + expert_module_t* expert_hdcp2; + + msg_table = wmem_map_new(wmem_epan_scope(), g_direct_hash, g_direct_equal); + for(i=0; i<array_length(msg_info); i++) { + wmem_map_insert(msg_table, + GUINT_TO_POINTER((guint)msg_info[i].id), + (gpointer)(&msg_info[i])); + } + + proto_hdcp2 = proto_register_protocol("High bandwidth Digital Content Protection version 2", "HDCP2", "hdcp2"); + + hdcp2_module = prefs_register_protocol_obsolete(proto_hdcp2); + prefs_register_obsolete_preference(hdcp2_module, "enable"); + + proto_register_field_array(proto_hdcp2, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + expert_hdcp2 = expert_register_protocol(proto_hdcp2); + expert_register_field_array(expert_hdcp2, ei, array_length(ei)); + + register_dissector("hdcp2", dissect_hdcp2, proto_hdcp2); +} + +void +proto_reg_handoff_hdcp2(void) +{ + static gboolean prefs_initialized = FALSE; + + if (!prefs_initialized) { + heur_dissector_add ("tcp", dissect_hdcp2, "HDCP2 over TCP", "hdcp2_tcp", proto_hdcp2, HEURISTIC_DISABLE); + + prefs_initialized = TRUE; + } +} + +/* + * Editor modelines - https://www.wireshark.org/tools/modelines.html + * + * Local variables: + * c-basic-offset: 4 + * tab-width: 8 + * indent-tabs-mode: nil + * End: + * + * vi: set shiftwidth=4 tabstop=8 expandtab: + * :indentSize=4:tabSize=8:noTabs=true: + */ |