X-Git-Url: https://git.decadent.org.uk/gitweb/?p=odhcp6c.git;a=blobdiff_plain;f=src%2Fscript.c;h=1533510dbab56c8d8394298ecf48c844b9255380;hp=219d034d82f75f75cbcd3da4d1e1ddd238d13d2f;hb=6326ab374ede4fff1e8019a50d4b9854b8db7625;hpb=68042ddafe0e1a3498b6c7a57ec8d2d20f25650b

diff --git a/src/script.c b/src/script.c
index 219d034..1533510 100644
--- a/src/script.c
+++ b/src/script.c
@@ -22,6 +22,7 @@
 #include <unistd.h>
 #include <inttypes.h>
 #include <arpa/inet.h>
+#include <sys/wait.h>
 #include <netinet/in.h>
 
 #include "odhcp6c.h"
@@ -39,14 +40,27 @@ static const int8_t hexvals[] = {
 };
 
 
+static char action[16] = "";
+static char *argv[4] = {NULL, NULL, action, NULL};
+static volatile pid_t running = 0;
+static time_t started;
 
-static char *argv[4] = {NULL, NULL, NULL, NULL};
 
+static void script_sighandle(int signal)
+{
+	if (signal == SIGCHLD) {
+		pid_t child;
+		while ((child = waitpid(-1, NULL, WNOHANG)) > 0)
+			if (running == child)
+				running = 0;
+	}
+}
 
 int script_init(const char *path, const char *ifname)
 {
 	argv[0] = (char*)path;
 	argv[1] = (char*)ifname;
+	signal(SIGCHLD, script_sighandle);
 	return 0;
 }
 
@@ -91,7 +105,9 @@ static void ipv6_to_env(const char *name,
 		buf_len += strlen(&buf[buf_len]);
 		buf[buf_len++] = ' ';
 	}
-	buf[buf_len - 1] = '\0';
+	if (buf[buf_len - 1] == ' ')
+		buf_len--;
+	buf[buf_len] = '\0';
 	putenv(buf);
 }
 
@@ -104,14 +120,17 @@ static void fqdn_to_env(const char *name, const uint8_t *fqdn, size_t len)
 	char *buf = realloc(NULL, len + buf_len + 2);
 	memcpy(buf, name, buf_len);
 	buf[buf_len++] = '=';
-	int l = 1;
-	while (l > 0 && fqdn < fqdn_end) {
-		l = dn_expand(fqdn, fqdn_end, fqdn, &buf[buf_len], buf_size - buf_len);
+	while (fqdn < fqdn_end) {
+		int l = dn_expand(fqdn, fqdn_end, fqdn, &buf[buf_len], buf_size - buf_len);
+		if (l <= 0)
+			break;
 		fqdn += l;
 		buf_len += strlen(&buf[buf_len]);
 		buf[buf_len++] = ' ';
 	}
-	buf[buf_len - 1] = '\0';
+	if (buf[buf_len - 1] == ' ')
+		buf_len--;
+	buf[buf_len] = '\0';
 	putenv(buf);
 }
 
@@ -142,7 +161,10 @@ static void entry_to_env(const char *name, const void *data, size_t len, enum en
 {
 	size_t buf_len = strlen(name);
 	const struct odhcp6c_entry *e = data;
-	char *buf = realloc(NULL, buf_len + 2 + (len / sizeof(*e)) * 144);
+	// Worst case: ENTRY_PREFIX with iaid != 1 and exclusion
+	const size_t max_entry_len = (INET6_ADDRSTRLEN-1 + 5 + 22 + 15 + 10 +
+				      INET6_ADDRSTRLEN-1 + 11 + 1);
+	char *buf = realloc(NULL, buf_len + 2 + (len / sizeof(*e)) * max_entry_len);
 	memcpy(buf, name, buf_len);
 	buf[buf_len++] = '=';
 
@@ -150,34 +172,42 @@ static void entry_to_env(const char *name, const void *data, size_t len, enum en
 		inet_ntop(AF_INET6, &e[i].target, &buf[buf_len], INET6_ADDRSTRLEN);
 		buf_len += strlen(&buf[buf_len]);
 		if (type != ENTRY_HOST) {
-			buf_len += snprintf(&buf[buf_len], 6, "/%"PRIu16, e[i].length);
+			snprintf(&buf[buf_len], 6, "/%"PRIu16, e[i].length);
+			buf += strlen(&buf[buf_len]);
 			if (type == ENTRY_ROUTE) {
 				buf[buf_len++] = ',';
 				if (!IN6_IS_ADDR_UNSPECIFIED(&e[i].router)) {
 					inet_ntop(AF_INET6, &e[i].router, &buf[buf_len], INET6_ADDRSTRLEN);
 					buf_len += strlen(&buf[buf_len]);
 				}
-				buf_len += snprintf(&buf[buf_len], 24, ",%u", e[i].valid);
-				buf_len += snprintf(&buf[buf_len], 12, ",%u", e[i].priority);
+				snprintf(&buf[buf_len], 23, ",%u,%u", e[i].valid, e[i].priority);
+				buf += strlen(&buf[buf_len]);
 			} else {
-				buf_len += snprintf(&buf[buf_len], 24, ",%u,%u", e[i].preferred, e[i].valid);
+				snprintf(&buf[buf_len], 23, ",%u,%u", e[i].preferred, e[i].valid);
+				buf += strlen(&buf[buf_len]);
 			}
 
-			if (type == ENTRY_PREFIX && ntohl(e[i].iaid) != 1)
-				buf_len += snprintf(&buf[buf_len], 16, ",class=%08x", ntohl(e[i].iaid));
+			if (type == ENTRY_PREFIX && ntohl(e[i].iaid) != 1) {
+				snprintf(&buf[buf_len], 16, ",class=%08x", ntohl(e[i].iaid));
+				buf += strlen(&buf[buf_len]);
+			}
 
 			if (type == ENTRY_PREFIX && e[i].priority) {
 				// priority and router are abused for prefix exclusion
-				buf_len += snprintf(&buf[buf_len], 12, ",excluded=");
+				snprintf(&buf[buf_len], 11, ",excluded=");
+				buf_len += strlen(&buf[buf_len]);
 				inet_ntop(AF_INET6, &e[i].router, &buf[buf_len], INET6_ADDRSTRLEN);
 				buf_len += strlen(&buf[buf_len]);
-				buf_len += snprintf(&buf[buf_len], 24, "/%u", e[i].priority);
+				snprintf(&buf[buf_len], 12, "/%u", e[i].priority);
+				buf_len += strlen(&buf[buf_len]);
 			}
 		}
 		buf[buf_len++] = ' ';
 	}
 
-	buf[buf_len - 1] = '\0';
+	if (buf[buf_len - 1] == ' ')
+		buf_len--;
+	buf[buf_len] = '\0';
 	putenv(buf);
 }
 
@@ -196,14 +226,16 @@ static void search_to_env(const char *name, const uint8_t *start, size_t len)
 		*c++ = ' ';
 	}
 
-	c[-1] = '\0';
+	if (c[-1] == ' ')
+		c--;
+	*c = '\0';
 	putenv(buf);
 }
 
 
 static void int_to_env(const char *name, int value)
 {
-	size_t len = 12 + strlen(name);
+	size_t len = 13 + strlen(name);
 	char *buf = realloc(NULL, len);
 	snprintf(buf, len, "%s=%d", name, value);
 	putenv(buf);
@@ -258,7 +290,8 @@ static void s46_to_env(enum odhcp6c_state state, const uint8_t *data, size_t len
 			size_t prefix6len = rule->prefix6_len;
 			prefix6len = (prefix6len % 8 == 0) ? prefix6len / 8 : prefix6len / 8 + 1;
 
-			if (olen < sizeof(struct dhcpv6_s46_rule) + prefix6len)
+			if (prefix6len > sizeof(in6) ||
+			    olen < sizeof(struct dhcpv6_s46_rule) + prefix6len)
 				continue;
 
 			memcpy(&in6, rule->ipv6_prefix, prefix6len);
@@ -287,7 +320,8 @@ static void s46_to_env(enum odhcp6c_state state, const uint8_t *data, size_t len
 					size_t prefix6len = dmr->dmr_prefix6_len;
 					prefix6len = (prefix6len % 8 == 0) ? prefix6len / 8 : prefix6len / 8 + 1;
 
-					if (olen < sizeof(struct dhcpv6_s46_dmr) + prefix6len)
+					if (prefix6len > sizeof(in6) ||
+					    olen < sizeof(struct dhcpv6_s46_dmr) + prefix6len)
 						continue;
 
 					memcpy(&in6, dmr->dmr_ipv6_prefix, prefix6len);
@@ -306,7 +340,8 @@ static void s46_to_env(enum odhcp6c_state state, const uint8_t *data, size_t len
 			size_t prefix6len = bind->bindprefix6_len;
 			prefix6len = (prefix6len % 8 == 0) ? prefix6len / 8 : prefix6len / 8 + 1;
 
-			if (olen < sizeof(struct dhcpv6_s46_v4v6bind) + prefix6len)
+			if (prefix6len > sizeof(in6) ||
+			    olen < sizeof(struct dhcpv6_s46_v4v6bind) + prefix6len)
 				continue;
 
 			memcpy(&in6, bind->bind_ipv6_prefix, prefix6len);
@@ -336,41 +371,63 @@ static void s46_to_env(enum odhcp6c_state state, const uint8_t *data, size_t len
 }
 
 
-void script_call(const char *status)
+void script_call(const char *status, int delay, bool resume)
 {
-	size_t dns_len, search_len, custom_len, sntp_ip_len, ntp_ip_len, ntp_dns_len;
-	size_t sip_ip_len, sip_fqdn_len, aftr_name_len, cer_len, addr_len;
-	size_t s46_mapt_len, s46_mape_len, s46_lw_len, passthru_len;
-
-	odhcp6c_expire();
-
-	struct in6_addr *addr = odhcp6c_get_state(STATE_SERVER_ADDR, &addr_len);
-	struct in6_addr *dns = odhcp6c_get_state(STATE_DNS, &dns_len);
-	uint8_t *search = odhcp6c_get_state(STATE_SEARCH, &search_len);
-	uint8_t *custom = odhcp6c_get_state(STATE_CUSTOM_OPTS, &custom_len);
-	struct in6_addr *sntp = odhcp6c_get_state(STATE_SNTP_IP, &sntp_ip_len);
-	struct in6_addr *ntp = odhcp6c_get_state(STATE_NTP_IP, &ntp_ip_len);
-	uint8_t *ntp_dns = odhcp6c_get_state(STATE_NTP_FQDN, &ntp_dns_len);
-	struct in6_addr *sip = odhcp6c_get_state(STATE_SIP_IP, &sip_ip_len);
-	uint8_t *sip_fqdn = odhcp6c_get_state(STATE_SIP_FQDN, &sip_fqdn_len);
-	uint8_t *aftr_name = odhcp6c_get_state(STATE_AFTR_NAME, &aftr_name_len);
-	struct in6_addr *cer = odhcp6c_get_state(STATE_CER, &cer_len);
-	uint8_t *s46_mapt = odhcp6c_get_state(STATE_S46_MAPT, &s46_mapt_len);
-	uint8_t *s46_mape = odhcp6c_get_state(STATE_S46_MAPE, &s46_mape_len);
-	uint8_t *s46_lw = odhcp6c_get_state(STATE_S46_LW, &s46_lw_len);
-	uint8_t *passthru = odhcp6c_get_state(STATE_PASSTHRU, &passthru_len);
-
-	size_t prefix_len, address_len, ra_pref_len,
-		ra_route_len, ra_dns_len, ra_search_len;
-	uint8_t *prefix = odhcp6c_get_state(STATE_IA_PD, &prefix_len);
-	uint8_t *address = odhcp6c_get_state(STATE_IA_NA, &address_len);
-	uint8_t *ra_pref = odhcp6c_get_state(STATE_RA_PREFIX, &ra_pref_len);
-	uint8_t *ra_route = odhcp6c_get_state(STATE_RA_ROUTE, &ra_route_len);
-	uint8_t *ra_dns = odhcp6c_get_state(STATE_RA_DNS, &ra_dns_len);
-	uint8_t *ra_search = odhcp6c_get_state(STATE_RA_SEARCH, &ra_search_len);
-
-	// Don't set environment before forking, because env is leaky.
-	if (fork() == 0) {
+	time_t now = odhcp6c_get_milli_time() / 1000;
+	bool running_script = false;
+
+	if (running) {
+		kill(running, SIGTERM);
+		delay -= now - started;
+		running_script = true;
+	}
+
+	if (resume || !running_script || !action[0])
+		strncpy(action, status, sizeof(action) - 1);
+
+	pid_t pid = fork();
+	if (pid > 0) {
+		running = pid;
+		started = now;
+
+		if (!resume)
+			action[0] = 0;
+	} else if (pid == 0) {
+		size_t dns_len, search_len, custom_len, sntp_ip_len, ntp_ip_len, ntp_dns_len;
+		size_t sip_ip_len, sip_fqdn_len, aftr_name_len, cer_len, addr_len;
+		size_t s46_mapt_len, s46_mape_len, s46_lw_len, passthru_len;
+
+		signal(SIGTERM, SIG_DFL);
+		if (delay > 0) {
+			sleep(delay);
+			odhcp6c_expire();
+		}
+
+		struct in6_addr *addr = odhcp6c_get_state(STATE_SERVER_ADDR, &addr_len);
+		struct in6_addr *dns = odhcp6c_get_state(STATE_DNS, &dns_len);
+		uint8_t *search = odhcp6c_get_state(STATE_SEARCH, &search_len);
+		uint8_t *custom = odhcp6c_get_state(STATE_CUSTOM_OPTS, &custom_len);
+		struct in6_addr *sntp = odhcp6c_get_state(STATE_SNTP_IP, &sntp_ip_len);
+		struct in6_addr *ntp = odhcp6c_get_state(STATE_NTP_IP, &ntp_ip_len);
+		uint8_t *ntp_dns = odhcp6c_get_state(STATE_NTP_FQDN, &ntp_dns_len);
+		struct in6_addr *sip = odhcp6c_get_state(STATE_SIP_IP, &sip_ip_len);
+		uint8_t *sip_fqdn = odhcp6c_get_state(STATE_SIP_FQDN, &sip_fqdn_len);
+		uint8_t *aftr_name = odhcp6c_get_state(STATE_AFTR_NAME, &aftr_name_len);
+		struct in6_addr *cer = odhcp6c_get_state(STATE_CER, &cer_len);
+		uint8_t *s46_mapt = odhcp6c_get_state(STATE_S46_MAPT, &s46_mapt_len);
+		uint8_t *s46_mape = odhcp6c_get_state(STATE_S46_MAPE, &s46_mape_len);
+		uint8_t *s46_lw = odhcp6c_get_state(STATE_S46_LW, &s46_lw_len);
+		uint8_t *passthru = odhcp6c_get_state(STATE_PASSTHRU, &passthru_len);
+
+		size_t prefix_len, address_len, ra_pref_len,
+			ra_route_len, ra_dns_len, ra_search_len;
+		uint8_t *prefix = odhcp6c_get_state(STATE_IA_PD, &prefix_len);
+		uint8_t *address = odhcp6c_get_state(STATE_IA_NA, &address_len);
+		uint8_t *ra_pref = odhcp6c_get_state(STATE_RA_PREFIX, &ra_pref_len);
+		uint8_t *ra_route = odhcp6c_get_state(STATE_RA_ROUTE, &ra_route_len);
+		uint8_t *ra_dns = odhcp6c_get_state(STATE_RA_DNS, &ra_dns_len);
+		uint8_t *ra_search = odhcp6c_get_state(STATE_RA_SEARCH, &ra_search_len);
+
 		ipv6_to_env("SERVER", addr, addr_len / sizeof(*addr));
 		ipv6_to_env("RDNSS", dns, dns_len / sizeof(*dns));
 		ipv6_to_env("SNTP_IP", sntp, sntp_ip_len / sizeof(*sntp));
@@ -406,11 +463,7 @@ void script_call(const char *status)
 		script_hexlify(&buf[9], passthru, passthru_len);
 		putenv(buf);
 
-		argv[2] = (char*)status;
 		execv(argv[0], argv);
 		_exit(128);
 	}
-
-	// Delete lost prefixes and user opts
-	odhcp6c_clear_state(STATE_CUSTOM_OPTS);
 }