/* en50221 encoder An implementation for libdvb an implementation for the en50221 transport layer Copyright (C) 2004, 2005 Manu Abraham Copyright (C) 2005 Julian Scheel (julian at jusst dot de) Copyright (C) 2006 Andrew de Quincey (adq_dvb@lidskialf.net) This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include #include #include #include #include "en50221_app_ca.h" #include "asn_1.h" // tags supported by this resource #define TAG_CA_INFO_ENQUIRY 0x9f8030 #define TAG_CA_INFO 0x9f8031 #define TAG_CA_PMT 0x9f8032 #define TAG_CA_PMT_REPLY 0x9f8033 struct en50221_app_ca { struct en50221_app_send_functions *funcs; en50221_app_ca_info_callback ca_info_callback; void *ca_info_callback_arg; en50221_app_ca_pmt_reply_callback ca_pmt_reply_callback; void *ca_pmt_reply_callback_arg; pthread_mutex_t lock; }; struct ca_pmt_descriptor { uint8_t *descriptor; uint16_t length; struct ca_pmt_descriptor *next; }; struct ca_pmt_stream { uint8_t stream_type; uint16_t pid; struct ca_pmt_descriptor *descriptors; uint32_t descriptors_length; uint32_t descriptors_count; struct ca_pmt_stream *next; }; static int en50221_ca_extract_pmt_descriptors(struct mpeg_pmt_section *pmt, struct ca_pmt_descriptor **outdescriptors); static int en50221_ca_extract_streams(struct mpeg_pmt_section *pmt, struct ca_pmt_stream **outstreams); static void en50221_ca_try_move_pmt_descriptors(struct ca_pmt_descriptor **pmt_descriptors, struct ca_pmt_stream **pmt_streams); static uint32_t en50221_ca_calculate_length(struct ca_pmt_descriptor *pmt_descriptors, uint32_t *pmt_descriptors_length, struct ca_pmt_stream *pmt_streams); static int en50221_app_ca_parse_info(struct en50221_app_ca *ca, uint8_t slot_id, uint16_t session_number, uint8_t * data, uint32_t data_length); static int en50221_app_ca_parse_reply(struct en50221_app_ca *ca, uint8_t slot_id, uint16_t session_number, uint8_t * data, uint32_t data_length); struct en50221_app_ca *en50221_app_ca_create(struct en50221_app_send_functions *funcs) { struct en50221_app_ca *ca = NULL; // create structure and set it up ca = malloc(sizeof(struct en50221_app_ca)); if (ca == NULL) { return NULL; } ca->funcs = funcs; ca->ca_info_callback = NULL; ca->ca_pmt_reply_callback = NULL; pthread_mutex_init(&ca->lock, NULL); // done return ca; } void en50221_app_ca_destroy(struct en50221_app_ca *ca) { pthread_mutex_destroy(&ca->lock); free(ca); } void en50221_app_ca_register_info_callback(struct en50221_app_ca *ca, en50221_app_ca_info_callback callback, void *arg) { pthread_mutex_lock(&ca->lock); ca->ca_info_callback = callback; ca->ca_info_callback_arg = arg; pthread_mutex_unlock(&ca->lock); } void en50221_app_ca_register_pmt_reply_callback(struct en50221_app_ca *ca, en50221_app_ca_pmt_reply_callback callback, void *arg) { pthread_mutex_lock(&ca->lock); ca->ca_pmt_reply_callback = callback; ca->ca_pmt_reply_callback_arg = arg; pthread_mutex_unlock(&ca->lock); } int en50221_app_ca_info_enq(struct en50221_app_ca *ca, uint16_t session_number) { uint8_t data[4]; data[0] = (TAG_CA_INFO_ENQUIRY >> 16) & 0xFF; data[1] = (TAG_CA_INFO_ENQUIRY >> 8) & 0xFF; data[2] = TAG_CA_INFO_ENQUIRY & 0xFF; data[3] = 0; return ca->funcs->send_data(ca->funcs->arg, session_number, data, 4); } int en50221_app_ca_pmt(struct en50221_app_ca *ca, uint16_t session_number, uint8_t * ca_pmt, uint32_t ca_pmt_length) { uint8_t buf[10]; // set up the tag buf[0] = (TAG_CA_PMT >> 16) & 0xFF; buf[1] = (TAG_CA_PMT >> 8) & 0xFF; buf[2] = TAG_CA_PMT & 0xFF; // encode the length field int length_field_len; if ((length_field_len = asn_1_encode(ca_pmt_length, buf + 3, 3)) < 0) { return -1; } // build the iovecs struct iovec iov[2]; iov[0].iov_base = buf; iov[0].iov_len = 3 + length_field_len; iov[1].iov_base = ca_pmt; iov[1].iov_len = ca_pmt_length; // create the data and send it return ca->funcs->send_datav(ca->funcs->arg, session_number, iov, 2); } int en50221_app_ca_message(struct en50221_app_ca *ca, uint8_t slot_id, uint16_t session_number, uint32_t resource_id, uint8_t * data, uint32_t data_length) { (void) resource_id; // get the tag if (data_length < 3) { print(LOG_LEVEL, ERROR, 1, "Received short data\n"); return -1; } uint32_t tag = (data[0] << 16) | (data[1] << 8) | data[2]; switch (tag) { case TAG_CA_INFO: return en50221_app_ca_parse_info(ca, slot_id, session_number, data + 3, data_length - 3); case TAG_CA_PMT_REPLY: return en50221_app_ca_parse_reply(ca, slot_id, session_number, data + 3, data_length - 3); } print(LOG_LEVEL, ERROR, 1, "Received unexpected tag %x\n", tag); return -1; } int en50221_ca_format_pmt(struct mpeg_pmt_section *pmt, uint8_t * data, uint32_t data_length, int move_ca_descriptors, uint8_t ca_pmt_list_management, uint8_t ca_pmt_cmd_id) { struct ca_pmt_descriptor *pmt_descriptors = NULL; uint32_t pmt_descriptors_length = 0; struct ca_pmt_stream *pmt_streams = NULL; uint32_t total_required_length = 0; struct ca_pmt_descriptor *cur_d; struct ca_pmt_stream *cur_s; int result = -1; // extract the descriptors and streams if (en50221_ca_extract_pmt_descriptors(pmt, &pmt_descriptors)) goto cleanup; if (en50221_ca_extract_streams(pmt, &pmt_streams)) goto cleanup; // try and merge them if we have no PMT descriptors if ((pmt_descriptors == NULL) && move_ca_descriptors) { en50221_ca_try_move_pmt_descriptors(&pmt_descriptors, &pmt_streams); } // calculate the length of all descriptors/streams and the total length required total_required_length = en50221_ca_calculate_length(pmt_descriptors, &pmt_descriptors_length, pmt_streams); // ensure we were supplied with enough data if (total_required_length > data_length) { goto cleanup; } // format the start of the PMT uint32_t data_pos = 0; data[data_pos++] = ca_pmt_list_management; data[data_pos++] = mpeg_pmt_section_program_number(pmt) >> 8; data[data_pos++] = mpeg_pmt_section_program_number(pmt); data[data_pos++] = (pmt->head.version_number << 1) | pmt->head. current_next_indicator; data[data_pos++] = (pmt_descriptors_length >> 8) & 0x0f; data[data_pos++] = pmt_descriptors_length; // append the PMT descriptors if (pmt_descriptors_length) { data[data_pos++] = ca_pmt_cmd_id; cur_d = pmt_descriptors; while (cur_d) { memcpy(data + data_pos, cur_d->descriptor, cur_d->length); data_pos += cur_d->length; cur_d = cur_d->next; } } // now, append the streams cur_s = pmt_streams; while (cur_s) { data[data_pos++] = cur_s->stream_type; data[data_pos++] = (cur_s->pid >> 8) & 0x1f; data[data_pos++] = cur_s->pid; data[data_pos++] = (cur_s->descriptors_length >> 8) & 0x0f; data[data_pos++] = cur_s->descriptors_length; // append the stream descriptors if (cur_s->descriptors_length) { data[data_pos++] = ca_pmt_cmd_id; cur_d = cur_s->descriptors; while (cur_d) { memcpy(data + data_pos, cur_d->descriptor, cur_d->length); data_pos += cur_d->length; cur_d = cur_d->next; } } cur_s = cur_s->next; } result = data_pos; cleanup: // free the PMT descriptors cur_d = pmt_descriptors; while (cur_d) { struct ca_pmt_descriptor *next = cur_d->next; free(cur_d); cur_d = next; } // free the streams cur_s = pmt_streams; while (cur_s) { struct ca_pmt_stream *next_s = cur_s->next; // free the stream descriptors cur_d = cur_s->descriptors; while (cur_d) { struct ca_pmt_descriptor *next_d = cur_d->next; free(cur_d); cur_d = next_d; } free(cur_s); cur_s = next_s; } return result; } static int en50221_ca_extract_pmt_descriptors(struct mpeg_pmt_section *pmt, struct ca_pmt_descriptor **outdescriptors) { struct ca_pmt_descriptor *descriptors = NULL; struct ca_pmt_descriptor *descriptors_tail = NULL; struct ca_pmt_descriptor *cur_d; struct descriptor *cur_descriptor; mpeg_pmt_section_descriptors_for_each(pmt, cur_descriptor) { if (cur_descriptor->tag == dtag_mpeg_ca) { // create a new structure for this one struct ca_pmt_descriptor *new_d = malloc(sizeof(struct ca_pmt_descriptor)); if (new_d == NULL) { goto error_exit; } new_d->descriptor = (uint8_t *) cur_descriptor; new_d->length = cur_descriptor->len + 2; new_d->next = NULL; // append it to the list if (descriptors == NULL) { descriptors = new_d; } else { descriptors_tail->next = new_d; } descriptors_tail = new_d; } } *outdescriptors = descriptors; return 0; error_exit: cur_d = descriptors; while (cur_d) { struct ca_pmt_descriptor *next = cur_d->next; free(cur_d); cur_d = next; } return -1; } static int en50221_ca_extract_streams(struct mpeg_pmt_section *pmt, struct ca_pmt_stream **outstreams) { struct ca_pmt_stream *streams = NULL; struct ca_pmt_stream *streams_tail = NULL; struct mpeg_pmt_stream *cur_stream; struct descriptor *cur_descriptor; struct ca_pmt_stream *cur_s; mpeg_pmt_section_streams_for_each(pmt, cur_stream) { struct ca_pmt_descriptor *descriptors_tail = NULL; // create a new structure struct ca_pmt_stream *new_s = malloc(sizeof(struct ca_pmt_stream)); if (new_s == NULL) { goto exit_cleanup; } new_s->stream_type = cur_stream->stream_type; new_s->pid = cur_stream->pid; new_s->descriptors = NULL; new_s->next = NULL; new_s->descriptors_count = 0; // append it to the list if (streams == NULL) { streams = new_s; } else { streams_tail->next = new_s; } streams_tail = new_s; // now process the descriptors mpeg_pmt_stream_descriptors_for_each(cur_stream, cur_descriptor) { if (cur_descriptor->tag == dtag_mpeg_ca) { // create a new structure struct ca_pmt_descriptor *new_d = malloc(sizeof(struct ca_pmt_descriptor)); if (new_d == NULL) { goto exit_cleanup; } new_d->descriptor = (uint8_t *) cur_descriptor; new_d->length = cur_descriptor->len + 2; new_d->next = NULL; // append it to the list if (new_s->descriptors == NULL) { new_s->descriptors = new_d; } else { descriptors_tail->next = new_d; } descriptors_tail = new_d; new_s->descriptors_count++; } } } *outstreams = streams; return 0; exit_cleanup: // free the streams cur_s = streams; while (cur_s) { struct ca_pmt_stream *next_s = cur_s->next; // free the stream descriptors struct ca_pmt_descriptor *cur_d = cur_s->descriptors; while (cur_d) { struct ca_pmt_descriptor *next_d = cur_d->next; free(cur_d); cur_d = next_d; } free(cur_s); cur_s = next_s; } return -1; } static void en50221_ca_try_move_pmt_descriptors(struct ca_pmt_descriptor **pmt_descriptors, struct ca_pmt_stream **pmt_streams) { // get the first stream struct ca_pmt_stream *first_stream = *pmt_streams; if (first_stream == NULL) return; // Check that all the other streams with CA descriptors have exactly the same CA descriptors struct ca_pmt_stream *cur_stream = first_stream->next; while (cur_stream) { // if there are differing numbers of descriptors, exit right now if (cur_stream->descriptors_count != first_stream->descriptors_count) return; // now verify the descriptors match struct ca_pmt_descriptor *cur_descriptor = cur_stream->descriptors; struct ca_pmt_descriptor *first_cur_descriptor = first_stream->descriptors; while (cur_descriptor) { // check the descriptors are the same length if (cur_descriptor->length != first_cur_descriptor->length) return; // check their contents match if (memcmp(cur_descriptor->descriptor, first_cur_descriptor->descriptor, cur_descriptor->length)) { return; } // move to next cur_descriptor = cur_descriptor->next; first_cur_descriptor = first_cur_descriptor->next; } // move to next cur_stream = cur_stream->next; } // if we end up here, all descriptors in all streams matched // hook the first stream's descriptors into the PMT's *pmt_descriptors = first_stream->descriptors; first_stream->descriptors = NULL; first_stream->descriptors_count = 0; // now free up all the descriptors in the other streams cur_stream = first_stream->next; while (cur_stream) { struct ca_pmt_descriptor *cur_descriptor = cur_stream->descriptors; while (cur_descriptor) { struct ca_pmt_descriptor *next = cur_descriptor->next; free(cur_descriptor); cur_descriptor = next; } cur_stream->descriptors = NULL; cur_stream->descriptors_count = 0; cur_stream = cur_stream->next; } } static uint32_t en50221_ca_calculate_length(struct ca_pmt_descriptor *pmt_descriptors, uint32_t *pmt_descriptors_length, struct ca_pmt_stream *pmt_streams) { uint32_t total_required_length = 6; // header struct ca_pmt_stream *cur_s; // calcuate the PMT descriptors length (*pmt_descriptors_length) = 0; struct ca_pmt_descriptor *cur_d = pmt_descriptors; while (cur_d) { (*pmt_descriptors_length) += cur_d->length; cur_d = cur_d->next; } // add on 1 byte for the ca_pmt_cmd_id if we have some descriptors. if (*pmt_descriptors_length) (*pmt_descriptors_length)++; // update the total required length total_required_length += *pmt_descriptors_length; // calculate the length of descriptors in the streams cur_s = pmt_streams; while (cur_s) { // calculate the size of descriptors in this stream cur_s->descriptors_length = 0; cur_d = cur_s->descriptors; while (cur_d) { cur_s->descriptors_length += cur_d->length; cur_d = cur_d->next; } // add on 1 byte for the ca_pmt_cmd_id if we have some descriptors. if (cur_s->descriptors_length) cur_s->descriptors_length++; // update the total required length; total_required_length += 5 + cur_s->descriptors_length; cur_s = cur_s->next; } // done return total_required_length; } static int en50221_app_ca_parse_info(struct en50221_app_ca *ca, uint8_t slot_id, uint16_t session_number, uint8_t * data, uint32_t data_length) { // first of all, decode the length field uint16_t asn_data_length; int length_field_len; if ((length_field_len = asn_1_decode(&asn_data_length, data, data_length)) < 0) { print(LOG_LEVEL, ERROR, 1, "ASN.1 decode error\n"); return -1; } // check it if (asn_data_length > (data_length - length_field_len)) { print(LOG_LEVEL, ERROR, 1, "Received short data\n"); return -1; } data += length_field_len; // parse uint32_t ca_id_count = asn_data_length / 2; // byteswap the IDs uint16_t *ids = (uint16_t *) data; uint32_t i; for (i = 0; i < ca_id_count; i++) { bswap16(data); data += 2; } // tell the app pthread_mutex_lock(&ca->lock); en50221_app_ca_info_callback cb = ca->ca_info_callback; void *cb_arg = ca->ca_info_callback_arg; pthread_mutex_unlock(&ca->lock); if (cb) { return cb(cb_arg, slot_id, session_number, ca_id_count, ids); } return 0; } static int en50221_app_ca_parse_reply(struct en50221_app_ca *ca, uint8_t slot_id, uint16_t session_number, uint8_t * data, uint32_t data_length) { // first of all, decode the length field uint16_t asn_data_length; int length_field_len; if ((length_field_len = asn_1_decode(&asn_data_length, data, data_length)) < 0) { print(LOG_LEVEL, ERROR, 1, "ASN.1 decode error\n"); return -1; } // check it if (asn_data_length < 4) { print(LOG_LEVEL, ERROR, 1, "Received short data\n"); return -1; } if (asn_data_length > (data_length - length_field_len)) { print(LOG_LEVEL, ERROR, 1, "Received short data\n"); return -1; } data += length_field_len; data_length -= length_field_len; // process the reply table to fix endian issues uint32_t pos = 4; bswap16(data); while (pos < asn_data_length) { bswap16(data + pos); pos += 3; } // tell the app pthread_mutex_lock(&ca->lock); en50221_app_ca_pmt_reply_callback cb = ca->ca_pmt_reply_callback; void *cb_arg = ca->ca_pmt_reply_callback_arg; pthread_mutex_unlock(&ca->lock); if (cb) { return cb(cb_arg, slot_id, session_number, (struct en50221_app_pmt_reply *) data, asn_data_length); } return 0; }