diff options
Diffstat (limited to 'src/ao_radio_cmac.c')
| -rw-r--r-- | src/ao_radio_cmac.c | 406 |
1 files changed, 406 insertions, 0 deletions
diff --git a/src/ao_radio_cmac.c b/src/ao_radio_cmac.c new file mode 100644 index 00000000..41fbbe1f --- /dev/null +++ b/src/ao_radio_cmac.c @@ -0,0 +1,406 @@ +/* + * Copyright © 2011 Keith Packard <keithp@keithp.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * 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 + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ + +#include "ao.h" + +#define AO_CMAC_KEY_LEN AO_AES_LEN +#define AO_CMAC_MAX_LEN (128 - AO_CMAC_KEY_LEN) + +static __xdata uint8_t ao_radio_cmac_mutex; +__pdata int16_t ao_radio_cmac_rssi; +static __xdata uint8_t cmac_data[AO_CMAC_MAX_LEN + AO_CMAC_KEY_LEN + 2 + AO_CMAC_KEY_LEN]; +static __pdata uint8_t ao_radio_cmac_len; + +static uint8_t +getnibble(void) +{ + int8_t b; + + b = ao_cmd_hexchar(getchar()); + if (b < 0) { + ao_cmd_status = ao_cmd_lex_error; + return 0; + } + return (uint8_t) b; +} + +static uint8_t +getbyte(void) +{ + uint8_t b; + b = getnibble() << 4; + b |= getnibble(); + return b; +} + +static uint8_t +round_len(uint8_t len) +{ + uint8_t rem; + + /* Make sure we transfer at least one packet, and + * then make sure every packet is full. Note that + * there is no length encoded, and that the receiver + * must deal with any extra bytes in the packet + */ + if (len < AO_CMAC_KEY_LEN) + len = AO_CMAC_KEY_LEN; + rem = len % AO_CMAC_KEY_LEN; + if (rem != 0) + len += (AO_CMAC_KEY_LEN - rem); + return len; +} + +/* + * Sign and deliver the data sitting in the cmac buffer + */ +static void +radio_cmac_send(uint8_t len) __reentrant +{ + uint8_t i; + + len = round_len(len); + /* Make sure the AES key is loaded */ + ao_config_get(); + +#if HAS_MONITOR + ao_set_monitor(0); +#endif + + ao_mutex_get(&ao_aes_mutex); + ao_aes_set_mode(ao_aes_mode_cbc_mac); + ao_aes_set_key(ao_config.aes_key); + ao_aes_zero_iv(); + for (i = 0; i < len; i += AO_CMAC_KEY_LEN) { + if (i + AO_CMAC_KEY_LEN < len) + ao_aes_run(&cmac_data[i], NULL); + else + ao_aes_run(&cmac_data[i], &cmac_data[len]); + } + ao_mutex_put(&ao_aes_mutex); + + ao_radio_send(cmac_data, len + AO_CMAC_KEY_LEN); +} + +/* + * Receive and validate an incoming packet + */ + +static int8_t +radio_cmac_recv(uint8_t len, uint16_t timeout) __reentrant +{ + uint8_t i; + + len = round_len(len); +#if HAS_MONITOR + ao_set_monitor(0); +#endif + if (timeout) + ao_alarm(timeout); + + i = ao_radio_recv(cmac_data, len + AO_CMAC_KEY_LEN + 2); + ao_clear_alarm(); + + if (!i) { + ao_radio_cmac_rssi = 0; + return AO_RADIO_CMAC_TIMEOUT; + } + + ao_radio_cmac_rssi = (int16_t) (((int8_t) cmac_data[len + AO_CMAC_KEY_LEN]) >> 1) - 74; + if (!(cmac_data[len + AO_CMAC_KEY_LEN +1] & PKT_APPEND_STATUS_1_CRC_OK)) + return AO_RADIO_CMAC_CRC_ERROR; + + ao_config_get(); + + /* Compute the packet signature + */ + ao_mutex_get(&ao_aes_mutex); + ao_aes_set_mode(ao_aes_mode_cbc_mac); + ao_aes_set_key(ao_config.aes_key); + ao_aes_zero_iv(); + for (i = 0; i < len; i += AO_CMAC_KEY_LEN) { + if (i + AO_CMAC_KEY_LEN < len) + ao_aes_run(&cmac_data[i], NULL); + else + ao_aes_run(&cmac_data[i], &cmac_data[len + AO_CMAC_KEY_LEN + 2]); + } + ao_mutex_put(&ao_aes_mutex); + + /* Check the packet signature against the signature provided + * over the link + */ + + if (memcmp(&cmac_data[len], + &cmac_data[len + AO_CMAC_KEY_LEN + 2], + AO_CMAC_KEY_LEN) != 0) { + return AO_RADIO_CMAC_MAC_ERROR; + } + + return AO_RADIO_CMAC_OK; +} + +int8_t +ao_radio_cmac_send(__xdata void *packet, uint8_t len) __reentrant +{ + if (len > AO_CMAC_MAX_LEN) + return AO_RADIO_CMAC_LEN_ERROR; + ao_mutex_get(&ao_radio_cmac_mutex); + memcpy(cmac_data, packet, len); + radio_cmac_send(len); + ao_mutex_put(&ao_radio_cmac_mutex); + return AO_RADIO_CMAC_OK; +} + +int8_t +ao_radio_cmac_recv(__xdata void *packet, uint8_t len, uint16_t timeout) __reentrant +{ + uint8_t i; + if (len > AO_CMAC_MAX_LEN) + return AO_RADIO_CMAC_LEN_ERROR; + ao_mutex_get(&ao_radio_cmac_mutex); + i = radio_cmac_recv(len, timeout); + if (i == AO_RADIO_CMAC_OK) + memcpy(packet, cmac_data, len); + ao_mutex_put(&ao_radio_cmac_mutex); + return i; +} + +static void +radio_cmac_send_cmd(void) __reentrant +{ + uint8_t i; + uint8_t len; + + ao_cmd_decimal(); + if (ao_cmd_status != ao_cmd_success) + return; + len = ao_cmd_lex_i; + if (len > AO_CMAC_MAX_LEN) { + ao_cmd_status = ao_cmd_syntax_error; + return; + } + flush(); + ao_mutex_get(&ao_radio_cmac_mutex); + len = ao_cmd_lex_i; + for (i = 0; i < len; i++) { + cmac_data[i] = getbyte(); + if (ao_cmd_status != ao_cmd_success) + return; + } + radio_cmac_send(len); + ao_mutex_put(&ao_radio_cmac_mutex); +} + +static void +radio_cmac_recv_cmd(void) __reentrant +{ + uint8_t len, i; + uint16_t timeout; + + ao_cmd_decimal(); + if (ao_cmd_status != ao_cmd_success) + return; + len = ao_cmd_lex_i; + ao_cmd_decimal(); + if (ao_cmd_status != ao_cmd_success) + return; + timeout = AO_MS_TO_TICKS(ao_cmd_lex_i); + ao_mutex_get(&ao_radio_cmac_mutex); + i = radio_cmac_recv(len, timeout); + if (i == AO_RADIO_CMAC_OK) { + printf ("PACKET "); + for (i = 0; i < len; i++) + printf("%02x", cmac_data[i]); + printf (" %d\n", ao_radio_cmac_rssi); + } else + printf ("ERROR %d %d\n", i, ao_radio_cmac_rssi); + ao_mutex_put(&ao_radio_cmac_mutex); +} + +static __xdata struct ao_launch_command command; +static __xdata struct ao_launch_query query; +static pdata uint16_t launch_serial; +static pdata uint8_t launch_channel; +static pdata uint16_t tick_offset; + +static void +launch_args(void) __reentrant +{ + ao_cmd_decimal(); + launch_serial = ao_cmd_lex_i; + ao_cmd_decimal(); + launch_channel = ao_cmd_lex_i; +} + +static int8_t +launch_query(void) +{ + uint8_t i; + int8_t r = AO_RADIO_CMAC_OK; + + tick_offset = ao_time(); + for (i = 0; i < 10; i++) { + printf ("."); flush(); + command.tick = ao_time(); + command.serial = launch_serial; + command.cmd = AO_LAUNCH_QUERY; + command.channel = launch_channel; + ao_radio_cmac_send(&command, sizeof (command)); + r = ao_radio_cmac_recv(&query, sizeof (query), AO_MS_TO_TICKS(500)); + if (r == AO_RADIO_CMAC_OK) + break; + } + tick_offset -= query.tick; + printf("\n"); flush(); + return r; +} + +static void +launch_report_cmd(void) __reentrant +{ + int8_t r; + + launch_args(); + if (ao_cmd_status != ao_cmd_success) + return; + r = launch_query(); + switch (r) { + case AO_RADIO_CMAC_OK: + if (query.valid) { + switch (query.arm_status) { + case ao_igniter_ready: + case ao_igniter_active: + printf ("Armed: "); + break; + default: + printf("Disarmed: "); + } + switch (query.igniter_status) { + default: + printf("unknown\n"); + break; + case ao_igniter_ready: + printf("igniter good\n"); + break; + case ao_igniter_open: + printf("igniter bad\n"); + break; + } + } else { + printf("Invalid channel %d\n", launch_channel); + } + printf("Rssi: %d\n", ao_radio_cmac_rssi); + break; + default: + printf("Error %d\n", r); + break; + } +} + +static void +launch_arm(void) __reentrant +{ + command.tick = ao_time() - tick_offset; + command.serial = launch_serial; + command.cmd = AO_LAUNCH_ARM; + command.channel = launch_channel; + ao_radio_cmac_send(&command, sizeof (command)); +} + +static void +launch_ignite(void) __reentrant +{ + command.tick = ao_time() - tick_offset; + command.serial = launch_serial; + command.cmd = AO_LAUNCH_FIRE; + command.channel = 0; + ao_radio_cmac_send(&command, sizeof (command)); +} + +static void +launch_fire_cmd(void) __reentrant +{ + static __xdata struct ao_launch_command command; + uint8_t secs; + uint8_t i; + int8_t r; + + launch_args(); + ao_cmd_decimal(); + secs = ao_cmd_lex_i; + if (ao_cmd_status != ao_cmd_success) + return; + r = launch_query(); + if (r != AO_RADIO_CMAC_OK) { + printf("query failed %d\n", r); + return; + } + + for (i = 0; i < 4; i++) { + printf("arm %d\n", i); flush(); + launch_arm(); + } + + secs = secs * 10 - 5; + if (secs > 100) + secs = 100; + for (i = 0; i < secs; i++) { + printf("fire %d\n", i); flush(); + launch_ignite(); + ao_delay(AO_MS_TO_TICKS(100)); + } +} + +static void +launch_arm_cmd(void) __reentrant +{ + uint8_t i; + int8_t r; + launch_args(); + r = launch_query(); + if (r != AO_RADIO_CMAC_OK) { + printf("query failed %d\n", r); + return; + } + for (i = 0; i < 4; i++) + launch_arm(); +} + +static void +launch_ignite_cmd(void) __reentrant +{ + uint8_t i; + launch_args(); + for (i = 0; i < 4; i++) + launch_ignite(); +} + +static __code struct ao_cmds ao_radio_cmac_cmds[] = { + { radio_cmac_send_cmd, "s <length>\0Send AES-CMAC packet. Bytes to send follow on next line" }, + { radio_cmac_recv_cmd, "S <length> <timeout>\0Receive AES-CMAC packet. Timeout in ms" }, + { launch_report_cmd, "l <serial> <channel>\0Get remote launch status" }, + { launch_fire_cmd, "f <serial> <channel> <secs>\0Fire remote igniter" }, + { launch_arm_cmd, "a <serial> <channel>\0Arm remote igniter" }, + { launch_ignite_cmd, "i <serial> <channel>\0Pulse remote igniter" }, + { 0, NULL }, +}; + +void +ao_radio_cmac_init(void) +{ + ao_cmd_register(&ao_radio_cmac_cmds[0]); +} |