setting an AES encryption key (Y) needs a length-byte
[hmcfgusb] / hmland.c
index cde993b795df0b375841e64ca285894ffb578d54..0ec09a7d792ad033170b119177f2222a6484afc5 100644 (file)
--- a/hmland.c
+++ b/hmland.c
@@ -1,4 +1,4 @@
-/* HM-CFG-LAN emuldation for HM-CFG-USB
+/* HM-CFG-LAN emulation for HM-CFG-USB
  *
  * Copyright (c) 2013 Michael Gernoth <michael@gernoth.net>
  *
 #include <string.h>
 #include <strings.h>
 #include <poll.h>
+#include <signal.h>
 #include <errno.h>
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/stat.h>
+#include <fcntl.h>
 #include <netinet/in.h>
 #include <arpa/inet.h>
 #include <libusb-1.0/libusb.h>
@@ -38,6 +41,8 @@
 #include "hexdump.h"
 #include "hmcfgusb.h"
 
+#define PID_FILE "/var/run/hmland.pid"
+
 extern char *optarg;
 
 static int impersonate_hmlanif = 0;
@@ -56,6 +61,8 @@ static int verbose = 0;
 
 static int format_part_out(uint8_t **inpos, int inlen, uint8_t **outpos, int outlen, int len, int flags)
 {
+       const uint8_t nibble[16] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
+               'A', 'B', 'C', 'D', 'E', 'F'};
        uint8_t *buf_out = *outpos;
        uint8_t *outend = *outpos + outlen;
        uint8_t *inend = *inpos + inlen;
@@ -74,20 +81,13 @@ static int format_part_out(uint8_t **inpos, int inlen, uint8_t **outpos, int out
        }
 
        if (flags & FLAG_FORMAT_HEX) {
-               char hex[3];
-
-               memset(hex, 0, sizeof(hex));
-
                CHECK_AVAIL(len);
                CHECK_SPACE(len*2);
                for (i = 0; i < len; i++) {
-                       if (snprintf(hex, sizeof(hex), "%02X", **inpos) != 2) {
-                               fprintf(stderr, "Can't format hex-string!\n");
-                               return 0;
-                       }
-                       *inpos += 1;
-                       memcpy(*outpos, hex, 2);
-                       *outpos += 2;
+                       **outpos = nibble[((**inpos) & 0xf0) >> 4];
+                       *outpos += 1;
+                       **outpos = nibble[((**inpos) & 0xf)];
+                       *inpos += 1; *outpos += 1;
                }
        } else {
                CHECK_AVAIL(len);
@@ -114,14 +114,26 @@ static int format_part_out(uint8_t **inpos, int inlen, uint8_t **outpos, int out
        return *outpos - buf_out;
 }
 
+static uint8_t ascii_to_nibble(uint8_t a)
+{
+       uint8_t c = 0x00;
+
+       if ((a >= '0') && (a <= '9')) {
+               c = a - '0';
+       } else if ((a >= 'A') && (a <= 'F')) {
+               c = (a - 'A') + 10;
+       } else if ((a >= 'a') && (a <= 'f')) {
+               c = (a - 'a') + 10;
+       }
+
+       return c;
+}
+
 static int parse_part_in(uint8_t **inpos, int inlen, uint8_t **outpos, int outlen, int flags)
 {
        uint8_t *buf_out = *outpos;
        uint8_t *outend = *outpos + outlen;
        uint8_t *inend = *inpos + inlen;
-       char hex[3];
-
-       memset(hex, 0, sizeof(hex));
 
        if (flags & FLAG_LENGTH_BYTE) {
                int len = 0;
@@ -155,25 +167,26 @@ static int parse_part_in(uint8_t **inpos, int inlen, uint8_t **outpos, int outle
 
                CHECK_SPACE(1);
                CHECK_AVAIL(2);
-               memcpy(hex, *inpos, 2);
-               *inpos += 2;
 
-               **outpos = strtoul(hex, NULL, 16);
-               *outpos += 1;
+               **outpos = ascii_to_nibble(**inpos) << 4;
+               *inpos += 1;
+               **outpos |= ascii_to_nibble(**inpos);
+               *inpos += 1; *outpos += 1;
        }
 
        return *outpos - buf_out;
 }
 
-static void hmlan_format_out(uint8_t *buf, int buf_len, void *data)
+static int hmlan_format_out(uint8_t *buf, int buf_len, void *data)
 {
        uint8_t out[1024];
        uint8_t *outpos;
        uint8_t *inpos;
        int fd = *((int*)data);
+       int w;
 
        if (buf_len < 1)
-               return;
+               return 1;
 
        memset(out, 0, sizeof(out));
        outpos = out;
@@ -226,9 +239,16 @@ static void hmlan_format_out(uint8_t *buf, int buf_len, void *data)
                        hexdump(buf, buf_len, "Unknown> ");
                        break;
        }
-       write(fd, out, outpos-out);
        if (debug)
                fprintf(stderr, "LAN < %s\n", out);
+
+       w = write(fd, out, outpos-out);
+       if (w <= 0) {
+               perror("write");
+               return 0;
+       }
+
+       return 1;
 }
 
 static int hmlan_parse_in(int fd, void *data)
@@ -251,7 +271,7 @@ static int hmlan_parse_in(int fd, void *data)
                inpos = buf;
 
                if (debug)
-                       fprintf(stderr, "LAN > %s\n", buf);
+                       fprintf(stderr, "\nLAN > %s", buf);
 
                while (inpos < inend) {
                        uint8_t *instart = inpos;
@@ -278,7 +298,7 @@ static int hmlan_parse_in(int fd, void *data)
                        memset(out, 0, sizeof(out));
                        *outpos++ = *inpos++;
 
-                       switch(buf[0]) {
+                       switch(*instart) {
                                case 'S':
                                        parse_part_in(&inpos, (last-(inpos-instart)), &outpos, (sizeof(out)-(outpos-out)), 0);
                                        parse_part_in(&inpos, (last-(inpos-instart)), &outpos, (sizeof(out)-(outpos-out)), 0);
@@ -287,6 +307,10 @@ static int hmlan_parse_in(int fd, void *data)
                                        parse_part_in(&inpos, (last-(inpos-instart)), &outpos, (sizeof(out)-(outpos-out)), 0);
                                        parse_part_in(&inpos, (last-(inpos-instart)), &outpos, (sizeof(out)-(outpos-out)), FLAG_LENGTH_BYTE);
                                        break;
+                               case 'Y':
+                                       parse_part_in(&inpos, (last-(inpos-instart)), &outpos, (sizeof(out)-(outpos-out)), 0);
+                                       parse_part_in(&inpos, (last-(inpos-instart)), &outpos, (sizeof(out)-(outpos-out)), 0);
+                                       parse_part_in(&inpos, (last-(inpos-instart)), &outpos, (sizeof(out)-(outpos-out)), FLAG_LENGTH_BYTE);
                                default:
                                        parse_part_in(&inpos, (last-(inpos-instart)), &outpos, (sizeof(out)-(outpos-out)), FLAG_IGNORE_COMMAS);
                                        break;
@@ -304,9 +328,10 @@ static int hmlan_parse_in(int fd, void *data)
        return 1;
 }
 
-static int comm(int fd_in, int fd_out, int master_socket)
+static int comm(int fd_in, int fd_out, int master_socket, int flags)
 {
        struct hmcfgusb_dev *dev;
+       uint8_t out[0x40]; //FIXME!!!
        int quit = 0;
 
        hmcfgusb_set_debug(debug);
@@ -331,12 +356,15 @@ static int comm(int fd_in, int fd_out, int master_socket)
                }
        }
 
-       hmcfgusb_send(dev, (unsigned char*)"K", 1, 1);
+       memset(out, 0, sizeof(out));
+       out[0] = 'K';
+       hmcfgusb_send_null_frame(dev);
+       hmcfgusb_send(dev, out, sizeof(out), 1);
 
        while(!quit) {
                int fd;
 
-               fd = hmcfgusb_poll(dev, 3600);
+               fd = hmcfgusb_poll(dev, 1);     /* Wakeup device/bus at least once a second */
                if (fd >= 0) {
                        if (fd == master_socket) {
                                int client;
@@ -355,6 +383,9 @@ static int comm(int fd_in, int fd_out, int master_socket)
                        if (errno) {
                                perror("hmcfgusb_poll");
                                quit = 1;
+                       } else {
+                               /* periodically wakeup the device */
+                               hmcfgusb_send_null_frame(dev);
                        }
                }
        }
@@ -363,22 +394,95 @@ static int comm(int fd_in, int fd_out, int master_socket)
        return 1;
 }
 
-static int socket_server(int port, int daemon)
+void sigterm_handler(int sig)
 {
+       if (unlink(PID_FILE) == -1)
+               perror("Can't remove PID file");
+
+       exit(EXIT_SUCCESS);
+}
+
+#define FLAG_DAEMON    (1 << 0)
+#define FLAG_PID_FILE  (1 << 1)
+
+static int socket_server(char *iface, int port, int flags)
+{
+       struct sigaction sact;
        struct sockaddr_in sin;
        int sock;
        int n;
        pid_t pid;
 
-       if (daemon) {
+       if (flags & FLAG_DAEMON) {
+               FILE *pidfile = NULL;
+
+               if (flags & FLAG_PID_FILE) {
+                       int fd;
+
+                       fd = open(PID_FILE, O_CREAT | O_EXCL | O_WRONLY, 0644);
+                       if (fd == -1) {
+                               if (errno == EEXIST) {
+                                       pid_t old_pid;
+                                       pidfile = fopen(PID_FILE, "r");
+                                       if (!pidfile) {
+                                               perror("PID file " PID_FILE " already exists, already running?");
+                                               exit(EXIT_FAILURE);
+                                       }
+
+                                       if (fscanf(pidfile, "%u", &old_pid) != 1) {
+                                               fclose(pidfile);
+                                               fprintf(stderr, "Can't read old PID from " PID_FILE ", already running?\n");
+                                               exit(EXIT_FAILURE);
+                                       }
+
+                                       fclose(pidfile);
+
+                                       fprintf(stderr, "Already running with PID %u according to " PID_FILE "!\n", old_pid);
+                                       exit(EXIT_FAILURE);
+                               }
+                               perror("Can't create PID file " PID_FILE);
+                               exit(EXIT_FAILURE);
+                       }
+
+                       pidfile = fdopen(fd, "w");
+                       if (!pidfile) {
+                               perror("Can't reopen PID file fd");
+                               exit(EXIT_FAILURE);
+                       }
+
+                       memset(&sact, 0, sizeof(sact));
+                       sact.sa_handler = sigterm_handler;
+
+                       if (sigaction(SIGTERM, &sact, NULL) == -1) {
+                               perror("sigaction(SIGTERM)");
+                               exit(EXIT_FAILURE);
+                       }
+               }
+
                pid = fork();
                if (pid > 0) {
+                       if (pidfile) {
+                               fprintf(pidfile, "%u\n", pid);
+                               fclose(pidfile);
+                       }
+
                        printf("Daemon with PID %u started!\n", pid);
                        exit(EXIT_SUCCESS);
                } else if (pid < 0) {
                        perror("fork");
                        exit(EXIT_FAILURE);
                }
+
+               if (pidfile)
+                       fclose(pidfile);
+       }
+
+       memset(&sact, 0, sizeof(sact));
+       sact.sa_handler = SIG_IGN;
+
+       if (sigaction(SIGPIPE, &sact, NULL) == -1) {
+               perror("sigaction(SIGPIPE)");
+               exit(EXIT_FAILURE);
        }
 
        impersonate_hmlanif = 1;
@@ -398,7 +502,14 @@ static int socket_server(int port, int daemon)
        memset(&sin, 0, sizeof(sin));
        sin.sin_family = AF_INET;
        sin.sin_port = htons(port);
-       sin.sin_addr.s_addr = htonl(INADDR_ANY);
+       if (!iface) {
+               sin.sin_addr.s_addr = htonl(INADDR_ANY);
+       } else {
+               if (inet_pton(AF_INET, iface, &(sin.sin_addr.s_addr)) != 1) {
+                       perror("inet_ntop");
+                       return EXIT_FAILURE;
+               }
+       }
 
        if (bind(sock, (struct sockaddr*)&sin, sizeof(sin)) == -1) {
                perror("Can't bind socket");
@@ -435,7 +546,7 @@ static int socket_server(int port, int daemon)
                                        (client_addr & 0x000000ff));
                }
 
-               comm(client, client, sock);
+               comm(client, client, sock, flags);
 
                shutdown(client, SHUT_RDWR);
                close(client);
@@ -447,15 +558,15 @@ static int socket_server(int port, int daemon)
                                        (client_addr & 0x0000ff00) >> 8,
                                        (client_addr & 0x000000ff));
                }
-
+               sleep(1);
        }
 
        return EXIT_SUCCESS;
 }
 
-static int interactive_server(void)
+static int interactive_server(int flags)
 {
-       if (!comm(STDIN_FILENO, STDOUT_FILENO, -1))
+       if (!comm(STDIN_FILENO, STDOUT_FILENO, -1, flags))
                return EXIT_FAILURE;
 
        return EXIT_SUCCESS;
@@ -469,6 +580,8 @@ void hmlan_syntax(char *prog)
        fprintf(stderr, "\t-d\tdaemon mode\n");
        fprintf(stderr, "\t-h\tthis help\n");
        fprintf(stderr, "\t-i\tinteractive mode (connect HM-CFG-USB to terminal)\n");
+       fprintf(stderr, "\t-l ip\tlisten on given IP address only (for example 127.0.0.1)\n");
+       fprintf(stderr, "\t-P\tcreate PID file " PID_FILE " in daemon mode\n");
        fprintf(stderr, "\t-p n\tlisten on port n (default 1000)\n");
        fprintf(stderr, "\t-v\tverbose mode\n");
 
@@ -477,23 +590,27 @@ void hmlan_syntax(char *prog)
 int main(int argc, char **argv)
 {
        int port = 1000;
+       char *iface = NULL;
        int interactive = 0;
-       int daemon = 0;
+       int flags = 0;
        char *ep;
        int opt;
 
-       while((opt = getopt(argc, argv, "Ddhip:v")) != -1) {
+       while((opt = getopt(argc, argv, "DdhiPp:Rl:v")) != -1) {
                switch (opt) {
                        case 'D':
                                debug = 1;
                                verbose = 1;
                                break;
                        case 'd':
-                               daemon = 1;
+                               flags |= FLAG_DAEMON;
                                break;
                        case 'i':
                                interactive = 1;
                                break;
+                       case 'P':
+                               flags |= FLAG_PID_FILE;
+                               break;
                        case 'p':
                                port = strtoul(optarg, &ep, 10);
                                if (*ep != '\0') {
@@ -501,6 +618,12 @@ int main(int argc, char **argv)
                                        exit(EXIT_FAILURE);
                                }
                                break;
+                       case 'R':
+                               fprintf(stderr, "-R is no longer needed (1s wakeup is default)\n");
+                               break;
+                       case 'l':
+                               iface = optarg;
+                               break;
                        case 'v':
                                verbose = 1;
                                break;
@@ -515,8 +638,8 @@ int main(int argc, char **argv)
        }
        
        if (interactive) {
-               return interactive_server();
+               return interactive_server(flags);
        } else {
-               return socket_server(port, daemon);
+               return socket_server(iface, port, flags);
        }
 }
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