Support for multiple pairing modes.

Link key replacement.

7 files changed, 129 insertions, 39 deletions

diff --git a/hcid/hcid.conf b/hcid/hcid.conf
index 784e1d97..89645993 100644
--- a/hcid/hcid.conf
+++ b/hcid/hcid.conf
@@ -6,16 +6,22 @@
 
 # HCId options
 options {
-	# Automaticaly initialize new devices
+	# Automatically initialize new devices
 	autoinit yes;
 
 	# Security Manager mode
 	#   none - Security manager disabled
-	#   auto - Use local PIN for incomming connections
+	#   auto - Use local PIN for incoming connections
 	#   user - Always ask user for a PIN
 	#
 	security auto;
 
+	# Pairing mode
+	#   none  - Pairing disabled
+	#   multi - Allow pairing with already paired devices
+	#   once  - Pair once and deny successive attempts
+	pairing multi;
+
 	# PIN helper
 	pin_helper /bin/bluepin;
 }
@@ -38,9 +44,9 @@ device {
 
 	# Default link mode
 	#   none   - no specific policy 
-	#   accept - always accept incomming connections
-	#   master - become master on incomming connections,
-	#            deny role switch on outgoint connections
+	#   accept - always accept incoming connections
+	#   master - become master on incoming connections,
+	#            deny role switch on outgoing connections
 	#
 	#lm accept,master;
 	#
diff --git a/hcid/hcid.h b/hcid/hcid.h
index 0715db28..cfc034e4 100644
--- a/hcid/hcid.h
+++ b/hcid/hcid.h
@@ -59,6 +59,7 @@ struct hcid_opts {
 	char   *host_name;
 	int     auto_init;
 	int     security;
+	int     pairing;
 
 	char   *config_file;
 
@@ -77,6 +78,10 @@ extern struct hcid_opts hcid;
 #define HCID_SEC_AUTO	1
 #define HCID_SEC_USER	2
 
+#define HCID_PAIRING_NONE	0
+#define HCID_PAIRING_MULTI	1
+#define HCID_PAIRING_ONCE	2
+
 int read_config(char *file);
 
 gboolean io_stack_event(GIOChannel *chan, GIOCondition cond, gpointer data);
@@ -85,4 +90,4 @@ gboolean io_security_event(GIOChannel *chan, GIOCondition cond, gpointer data);
 void init_security_data(void);
 void start_security_manager(int hdev);
 void stop_security_manager(int hdev);
-void flush_link_keys(void);
+void toggle_pairing(int enable);
diff --git a/hcid/kword.c b/hcid/kword.c
index cc69db39..0486f21b 100644
--- a/hcid/kword.c
+++ b/hcid/kword.c
@@ -37,6 +37,7 @@ struct kword cfg_keyword[] = {
    { "device",   K_DEVICE	}, 
    { "autoinit", K_AUTOINIT	}, 
    { "security", K_SECURITY	}, 
+   { "pairing",  K_PAIRING	}, 
    { "pkt_type", K_PTYPE	}, 
    { "lm", 	 K_LM		}, 
    { "lp", 	 K_LP		}, 
@@ -62,6 +63,13 @@ struct kword sec_param[] = {
    { NULL , 0 }
 };
 
+struct kword pair_param[] = {
+   { "none",	 HCID_PAIRING_NONE	},
+   { "multi",	 HCID_PAIRING_MULTI	},
+   { "once",	 HCID_PAIRING_ONCE	},
+   { NULL , 0 }
+};
+
 int lineno;
 
 int find_keyword(struct kword *kw, char *str)
diff --git a/hcid/kword.h b/hcid/kword.h
index 854c91d0..10c54493 100644
--- a/hcid/kword.h
+++ b/hcid/kword.h
@@ -32,5 +32,6 @@ extern int lineno;
 
 extern struct kword cfg_keyword[]; 
 extern struct kword sec_param[];
+extern struct kword pair_param[];
 
 int find_keyword(struct kword *kw, char *str);
diff --git a/hcid/main.c b/hcid/main.c
index 37e6cf65..8a5371e5 100644
--- a/hcid/main.c
+++ b/hcid/main.c
@@ -249,7 +249,12 @@ static void init_defaults(void)
 
 static void sig_usr1(int sig)
 {
-	flush_link_keys();
+	toggle_pairing(0);
+}
+
+static void sig_usr2(int sig)
+{
+	toggle_pairing(1);
 }
 
 static void sig_term(int sig)
@@ -357,6 +362,8 @@ int main(int argc, char *argv[], char *env[])
 	/* Default HCId settings */
 	hcid.config_file = HCID_CONFIG_FILE;
 	hcid.host_name = get_host_name();
+	hcid.security  = HCID_SEC_AUTO;
+	hcid.pairing   = HCID_PAIRING_MULTI;
 
 	hcid.pin_file   = strdup(HCID_PIN_FILE);
 	hcid.pin_helper = strdup(HCID_PIN_HELPER);
@@ -412,6 +419,8 @@ int main(int argc, char *argv[], char *env[])
 	sigaction(SIGHUP, &sa, NULL);
 	sa.sa_handler = sig_usr1;
 	sigaction(SIGUSR1, &sa, NULL);
+	sa.sa_handler = sig_usr2;
+	sigaction(SIGUSR2, &sa, NULL);
 
 	sa.sa_handler = SIG_IGN;
 	sigaction(SIGCHLD, &sa, NULL);
diff --git a/hcid/parser.y b/hcid/parser.y
index ff2cd1c6..b7614f85 100644
--- a/hcid/parser.y
+++ b/hcid/parser.y
@@ -56,7 +56,7 @@ int yyerror(char *s);
 }
 
 %token K_OPTIONS K_DEVICE
-%token K_AUTOINIT K_SECURITY
+%token K_AUTOINIT K_SECURITY K_PAIRING
 %token K_PTYPE K_NAME K_CLASS K_LM K_LP K_AUTH K_ENCRYPT K_ISCAN K_PSCAN
 %token K_PINHELP
 %token K_YES K_NO
@@ -64,7 +64,7 @@ int yyerror(char *s);
 %token <str> WORD PATH STRING LIST
 %token <num> NUM
 
-%type  <num> bool pkt_type link_mode link_policy sec_mode
+%type  <num> bool pkt_type link_mode link_policy sec_mode pair_mode
 %type  <str> dev_name
 
 %%
@@ -93,6 +93,10 @@ hcid_opt:
 				hcid.security = $2;
 			}
 
+  | K_PAIRING pair_mode	{
+				hcid.pairing = $2;
+			}
+
   | K_PINHELP  PATH	{
 				if (hcid.pin_helper)
 					free(hcid.pin_helper);
@@ -117,6 +121,18 @@ sec_mode:
   | K_NO	{ 	$$ = HCID_SEC_NONE; 	}
   ;
 
+pair_mode:
+   WORD		{	
+			int opt = find_keyword(pair_param, $1);
+			if (opt < 0) {
+				cfg_error("Unknown pairing mode '%s'", $1);
+				$$ = 0;
+			} else
+				$$ = opt;
+		}
+  ;
+
+
 device_options: '{' device_opts '}'
 device_opts: | device_opt ';' | error ';' | device_opts device_opt ';';
 device_opt:
diff --git a/hcid/security.c b/hcid/security.c
index 75e44421..b7839c4c 100644
--- a/hcid/security.c
+++ b/hcid/security.c
@@ -53,29 +53,27 @@
 
 static GIOChannel *io_chan[HCI_MAX_DEV];
 
-/* Link Key handling */
+static int pairing;
 
-void flush_link_keys(void)
+void toggle_pairing(int enable)
 {
-	syslog(LOG_INFO, "Flushing link key database");
-	truncate(hcid.key_file, 0);
+	if (enable)
+		pairing = hcid.pairing;
+	else
+		pairing = 0;
+
+	syslog(LOG_INFO, "Pairing %s", pairing ? "enabled" : "disabled");
 }
 
+/* Link Key handling */
+
 /* This function is not reentrable */
-static struct link_key *get_link_key(bdaddr_t *sba, bdaddr_t *dba)
+static struct link_key *__get_link_key(int f, bdaddr_t *sba, bdaddr_t *dba)
 {
 	static struct link_key k;
 	struct link_key *key = NULL;
-	int f, r;
-
-	f = open(hcid.key_file, O_RDONLY);
-	if (f < 0) {
-		if (errno != ENOENT)
-			syslog(LOG_ERR, "Link key database open failed. %s(%d)",
-					strerror(errno), errno);
-		return NULL;
-	}
-
+	int r;
+	
 	while ((r = read_n(f, &k, sizeof(k)))) {
 		if (r < 0) {
 			syslog(LOG_ERR, "Link key database read failed. %s(%d)",
@@ -88,7 +86,20 @@ static struct link_key *get_link_key(bdaddr_t *sba, bdaddr_t *dba)
 			break;
 		}
 	}
-	
+	return key;
+}
+
+static struct link_key *get_link_key(bdaddr_t *sba, bdaddr_t *dba)
+{
+	struct link_key *key = NULL;
+	int f;
+
+	f = open(hcid.key_file, O_RDONLY);
+	if (f >= 0)
+		key = __get_link_key(f, sba, dba);
+	else if (errno != ENOENT)
+		syslog(LOG_ERR, "Link key database open failed. %s(%d)",
+				strerror(errno), errno);
 	close(f);
 	return key;
 }
@@ -114,24 +125,43 @@ static void link_key_request(int dev, bdaddr_t *sba, bdaddr_t *dba)
 static void save_link_key(struct link_key *key)
 {
 	char sa[40], da[40];
-	int f;
+	struct link_key *exist;
+	int f, err;
 
-	f = open(hcid.key_file, O_WRONLY | O_CREAT | O_APPEND, 0);
+	f = open(hcid.key_file, O_RDWR | O_CREAT, 0);
 	if (f < 0) {
 		syslog(LOG_ERR, "Link key database open failed. %s(%d)",
 				strerror(errno), errno);
 		return;
 	}
 
+	/* Check if key already exist */
+	exist = __get_link_key(f, &key->sba, &key->dba);
+
+	err = 0;
+
+	if (exist) {
+		off_t o = lseek(f, 0, SEEK_CUR);
+		err = lseek(f, o - sizeof(*key), SEEK_SET);
+	} else
+		err = fcntl(f, F_SETFL, O_APPEND);
+
+	if (err < 0) {
+		syslog(LOG_ERR, "Link key database seek failed. %s(%d)",
+				strerror(errno), errno);
+		goto failed;
+	}
+	
 	if (write_n(f, key, sizeof(*key)) < 0) {
 		syslog(LOG_ERR, "Link key database write failed. %s(%d)",
 				strerror(errno), errno);
 	}
 
-	close(f);
-
 	ba2str(&key->sba, sa); ba2str(&key->dba, da);
-	syslog(LOG_INFO, "Saving link key %s %s", sa, da);
+	syslog(LOG_INFO, "%s link key %s %s", exist ? "Replacing" : "Saving", sa, da);
+
+failed:
+	close(f);
 }
 
 static void link_key_notify(int dev, bdaddr_t *sba, void *ptr)
@@ -254,7 +284,7 @@ reject:
 	exit(0);
 }
 
-static void pin_code_request(int dev, bdaddr_t *ba)
+static void pin_code_request(int dev, bdaddr_t *sba, bdaddr_t *dba)
 {
 	struct hci_conn_info_req *cr;
 	struct hci_conn_info *ci;
@@ -263,25 +293,32 @@ static void pin_code_request(int dev, bdaddr_t *ba)
 	if (!cr)
 		return;
 
-	bacpy(&cr->bdaddr, ba);
+	bacpy(&cr->bdaddr, dba);
 	cr->type = ACL_LINK;
 	if (ioctl(dev, HCIGETCONNINFO, (unsigned long) cr) < 0) {
 		syslog(LOG_ERR, "Can't get conn info %s(%d)",
 					strerror(errno), errno);
-		/* Reject PIN */
-		hci_send_cmd(dev, OGF_LINK_CTL, OCF_PIN_CODE_NEG_REPLY, 6, ba);
-
-		free(cr);
-		return;
+		goto reject;
 	}
 	ci = cr->conn_info;
 
+	if (pairing == HCID_PAIRING_ONCE) {
+		struct link_key *key = get_link_key(sba, dba);
+		if (key) {
+			char ba[40];
+			ba2str(dba, ba);
+			syslog(LOG_WARNING, "PIN code request for already paired device %s", ba);
+			goto reject;
+		}
+	} else if (pairing == HCID_PAIRING_NONE)
+		goto reject;
+
 	if (hcid.security == HCID_SEC_AUTO) {
 		if (!ci->out) {
 			/* Incomming connection */
 			pin_code_reply_cp pr;
 			memset(&pr, 0, sizeof(pr));
-			bacpy(&pr.bdaddr, ba);
+			bacpy(&pr.bdaddr, dba);
 			memcpy(pr.pin_code, hcid.pin_code, hcid.pin_len);
 			pr.pin_len = hcid.pin_len;
 			hci_send_cmd(dev, OGF_LINK_CTL, OCF_PIN_CODE_REPLY,
@@ -297,6 +334,12 @@ static void pin_code_request(int dev, bdaddr_t *ba)
 		call_pin_helper(dev, ci);
 	}	
 	free(cr);
+	return;
+
+reject:
+	hci_send_cmd(dev, OGF_LINK_CTL, OCF_PIN_CODE_NEG_REPLY, 6, dba);
+	free(cr);
+	return;
 }
 
 gboolean io_security_event(GIOChannel *chan, GIOCondition cond, gpointer data)
@@ -337,7 +380,7 @@ gboolean io_security_event(GIOChannel *chan, GIOCondition cond, gpointer data)
 
 	switch (eh->evt) {
 	case EVT_PIN_CODE_REQ:
-		pin_code_request(dev, (bdaddr_t *) ptr);
+		pin_code_request(dev, &di->bdaddr, (bdaddr_t *) ptr);
 		break;
 
 	case EVT_LINK_KEY_REQ:
@@ -426,5 +469,7 @@ void init_security_data(void)
 		strcpy(hcid.pin_code, "BlueZ");
 		hcid.pin_len = 5;
 	}
+
+	pairing = hcid.pairing;
 	return;
 }