From 103d40f78446345f6f5b705139492418cf6ee953 Mon Sep 17 00:00:00 2001 From: Michael Gernoth Date: Fri, 11 Sep 2015 13:00:34 +0200 Subject: [PATCH] flash-ota: add AES-support for culfw-devices --- .gitignore | 2 + Makefile | 2 +- flash-ota.c | 56 +++++++++++++++++++------- hm.c | 114 ++++++++++++++++++++++++++++++++++++++++++++++++++++ hm.h | 7 +++- 5 files changed, 163 insertions(+), 18 deletions(-) create mode 100644 hm.c diff --git a/.gitignore b/.gitignore index d1ea703..df1fea6 100644 --- a/.gitignore +++ b/.gitignore @@ -10,6 +10,8 @@ flash-ota.d flash-ota.o firmware.d firmware.o +hm.d +hm.o hmcfgusb.d hmcfgusb.o hmland diff --git a/Makefile b/Makefile index 4af4fe7..bd8fbf7 100644 --- a/Makefile +++ b/Makefile @@ -6,7 +6,7 @@ CC=gcc HMLAN_OBJS=hmcfgusb.o hmland.o util.o HMSNIFF_OBJS=hmcfgusb.o hmsniff.o FLASH_HMCFGUSB_OBJS=hmcfgusb.o firmware.o util.o flash-hmcfgusb.o -FLASH_OTA_OBJS=hmcfgusb.o culfw.o firmware.o util.o flash-ota.o +FLASH_OTA_OBJS=hmcfgusb.o culfw.o firmware.o util.o flash-ota.o hm.o aes.o OBJS=$(HMLAN_OBJS) $(HMSNIFF_OBJS) $(FLASH_HMCFGUSB_OBJS) $(FLASH_OTA_OBJS) diff --git a/flash-ota.c b/flash-ota.c index 9ffdeb8..953ed34 100644 --- a/flash-ota.c +++ b/flash-ota.c @@ -1,6 +1,6 @@ /* flasher for HomeMatic-devices supporting OTA updates * - * Copyright (c) 2014 Michael Gernoth + * Copyright (c) 2014-15 Michael Gernoth * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to @@ -51,7 +51,7 @@ extern char *optarg; uint32_t hmid = 0; uint32_t my_hmid = 0; -char key[16] = {0}; +uint8_t key[16] = {0}; int32_t kNo = -1; /* Maximum payloadlen supported by IO */ @@ -179,6 +179,13 @@ static int parse_culfw(uint8_t *buf, int buf_len, void *data) rdata->version |= v; } break; + case 'E': + { + if (!strncmp((char*)buf, "ERR:CCA", 7)) { + fprintf(stderr, "CCA didn't complete, too much traffic\n"); + } + break; + } default: fprintf(stderr, "Unknown response from CUL: %s", buf); return 0; @@ -270,7 +277,7 @@ int send_hm_message(struct ota_dev *dev, struct recv_data *rdata, uint8_t *msg) } if (msg[CTL] & 0x20) { - int cnt = 3; + int cnt = 5; int pfd; do { errno = 0; @@ -284,18 +291,44 @@ int send_hm_message(struct ota_dev *dev, struct recv_data *rdata, uint8_t *msg) if (rdata->message_type == MESSAGE_TYPE_E) { if (rdata->message[TYPE] == 0x02) { if (rdata->message[PAYLOAD] == 0x04) { - printf("AES request received but not implemented for culfw!\n"); + int32_t req_kNo; + uint8_t challenge[6]; + uint8_t respbuf[16]; + uint8_t *resp; + + req_kNo = rdata->message[rdata->message[LEN]] / 2; + memcpy(challenge, &(rdata->message[PAYLOAD+1]), 6); + + if (req_kNo != kNo) { + fprintf(stderr, "AES request for unknown key %d!\n", req_kNo); + } else { + resp = hm_sign(key, challenge, msg, NULL, respbuf); + if (resp) { + uint8_t rbuf[64]; + + memset(rbuf, 0, sizeof(rbuf)); + rbuf[MSGID] = rdata->message[MSGID]; + rbuf[CTL] = rdata->message[CTL]; + rbuf[TYPE] = 0x03; + SET_SRC(rbuf, DST(rdata->message)); + SET_DST(rbuf, SRC(rdata->message)); + memcpy(&(rbuf[PAYLOAD]), resp, 16); + SET_LEN_FROM_PAYLOADLEN(rbuf, 16); + + return send_hm_message(dev, rdata, rbuf); + } + } } else if (rdata->message[PAYLOAD] >= 0x80 && rdata->message[PAYLOAD] <= 0x8f) { - printf("NACK\n"); + fprintf(stderr, "NACK\n"); } else { /* ACK or ACKinfo */ break; } } else { - printf("Unexpected message received: "); + fprintf(stderr, "Unexpected message received: "); for (i = 0; i < rdata->message[LEN]; i++) { - printf("%02x", rdata->message[i+1]); + fprintf(stderr, "%02x", rdata->message[i+1]); } - printf("\n"); + fprintf(stderr, "\n"); } } } while(cnt--); @@ -368,7 +401,6 @@ void flash_ota_syntax(char *prog) fprintf(stderr, "\t-C\t\tHMID of central (3 hex-bytes, no prefix, e.g. ABCDEF)\n"); fprintf(stderr, "\t-D\t\tHMID of device (3 hex-bytes, no prefix, e.g. 123456)\n"); fprintf(stderr, "\t-K\t\tKNO:KEY AES key-number and key (hex) separated by colon (Fhem hmKey attribute)\n"); - fprintf(stderr, "\t\t\tAES is currently not supported when using a culfw-device!\n"); } int main(int argc, char **argv) @@ -476,12 +508,6 @@ int main(int argc, char **argv) memset(&dev, 0, sizeof(struct ota_dev)); if (culfw_dev) { - if (kNo != -1) { - fprintf(stderr, "\nAES currently not supported with culfw-device!\n"); - flash_ota_syntax(argv[0]); - exit(EXIT_FAILURE); - } - printf("Opening culfw-device at path %s with speed %u\n", culfw_dev, bps); dev.culfw = culfw_init(culfw_dev, bps, parse_culfw, &rdata); if (!dev.culfw) { diff --git a/hm.c b/hm.c new file mode 100644 index 0000000..818081f --- /dev/null +++ b/hm.c @@ -0,0 +1,114 @@ +/* HomeMatic protocol-functions + * + * Copyright (c) 2014-15 Michael Gernoth + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to + * deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or + * sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "aes.h" +#include "hexdump.h" +#include "hm.h" + +static int debug = 0; + +uint8_t* hm_sign(uint8_t *key, uint8_t *challenge, uint8_t *m_frame, uint8_t *exp_auth, uint8_t *resp) +{ + uint8_t signkey[16]; + WORD ks[60]; + struct timeval tv; + int i; + + printf("AES-request with challenge: %02x%02x%02x%02x%02x%02x\n", + challenge[0], challenge[1], challenge[2], + challenge[3], challenge[4], challenge[5]); + + /* + * Build signing key by XORing the first 6 bytes of + * the key with the challenge. + */ + memcpy(signkey, key, sizeof(signkey)); + for (i = 0; i < 6; i++) { + signkey[i] ^= challenge[i]; + } + aes_key_setup(signkey, ks, 128); + + /* + * Generate payload for first encryption. + */ + gettimeofday(&tv, NULL); + resp[0] = tv.tv_sec >> 24 & 0xff; + resp[1] = tv.tv_sec >> 16 & 0xff; + resp[2] = tv.tv_sec >> 8 & 0xff; + resp[3] = tv.tv_sec & 0xff; + resp[4] = tv.tv_usec >> 8 & 0xff; + resp[5] = tv.tv_usec & 0xff; + memcpy(&(resp[6]), &(m_frame[MSGID]), 10); + + if (debug) + hexdump(resp, 16, "P > "); + + aes_encrypt(resp, resp, ks, 128); + + if (debug) + hexdump(resp, 16, "Pe > "); + + /* + * Device has to answer with the first 4 bytes of the + * encrypted payload to authenticate, so pass them to + * the caller. + */ + + if (exp_auth) { + memcpy(exp_auth, resp, 4); + } + + /* + * XOR parameters of the m_frame to the payload. + */ + for (i = 0; i < PAYLOADLEN(m_frame) - 1; i++) { + if (i == 16) { + break; + } + + resp[i] ^= m_frame[PAYLOAD + 1+ i]; + } + + if (debug) + hexdump(resp, 16, "Pe^ > "); + + /* + * Encrypt payload again + */ + aes_encrypt(resp, resp, ks, 128); + + if (debug) + hexdump(resp, 16, "Pe^e> "); + + return resp; +} diff --git a/hm.h b/hm.h index d0d7147..af98626 100644 --- a/hm.h +++ b/hm.h @@ -1,6 +1,6 @@ -/* HomeMatic defines +/* HomeMatic defines and functions * - * Copyright (c) 2014 Michael Gernoth + * Copyright (c) 2014-15 Michael Gernoth * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to @@ -34,3 +34,6 @@ #define SET_DST(buf, dst) do { buf[0x07] = (dst >> 16) & 0xff; buf[0x08] = (dst >> 8) & 0xff; buf[0x09] = dst & 0xff; } while(0) #define SET_LEN_FROM_PAYLOADLEN(buf, payloadlen) do { buf[0x00] = payloadlen + 0x09; } while(0) +#define PAYLOADLEN(buf) (buf[0x00] - 0x09) + +uint8_t* hm_sign(uint8_t *key, uint8_t *challenge, uint8_t *m_frame, uint8_t *exp_auth, uint8_t *resp); -- 2.39.2