extra: implemented module 'pppd_compat' which starts pppd compatible scripts ip-up, ip-down,

        and newly introduced -  ip-change, when radius CoA request received,
        also this module manages pppd compatible radattr.pppX files
core:   implemented module 'sigchld' which handles SIGCHLD signal,
        waits child processes to terminate and manages pid terminate handlers

2 files changed, 377 insertions, 0 deletions

diff --git a/accel-pptpd/extra/CMakeLists.txt b/accel-pptpd/extra/CMakeLists.txt
new file mode 100644
index 0000000..7b4b69b
--- /dev/null
+++ b/accel-pptpd/extra/CMakeLists.txt
@@ -0,0 +1,2 @@
+ADD_LIBRARY(pppd_compat SHARED pppd_compat.c)
+
diff --git a/accel-pptpd/extra/pppd_compat.c b/accel-pptpd/extra/pppd_compat.c
new file mode 100644
index 0000000..1cf6741
--- /dev/null
+++ b/accel-pptpd/extra/pppd_compat.c
@@ -0,0 +1,375 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <signal.h>
+#include <unistd.h>
+#include <sched.h>
+#include <limits.h>
+
+#include "triton.h"
+
+#include "events.h"
+#include "ppp.h"
+#include "log.h"
+#include "radius.h"
+#include "utils.h"
+#include "sigchld.h"
+
+static char *conf_ip_up = "/etc/ppp/ip-up";
+static char *conf_ip_down = "/etc/ppp/ip-down";
+static char *conf_ip_change = "/etc/ppp/ip-change";
+static char *conf_radattr_prefix = "/var/run/radattr.";
+static int conf_verbose = 0;
+
+static void *pd_key;
+
+struct pppd_compat_pd_t
+{
+	struct ppp_pd_t pd;
+	struct ppp_t *ppp;
+	struct sigchld_handler_t ip_up_hnd;
+	struct sigchld_handler_t ip_change_hnd;
+	struct sigchld_handler_t ip_down_hnd;
+	int radattr_saved:1;
+	int started:1;
+	int ip_change_res;
+};
+
+static void remove_radattr(struct ppp_t *ppp);
+static struct pppd_compat_pd_t *find_pd(struct ppp_t *ppp);
+static void fill_argv(char **argv, struct ppp_t *ppp, char *path);
+static void write_radattr(struct ppp_t *ppp, struct rad_packet_t *pack, int save_old);
+
+static void ip_up_handler(struct sigchld_handler_t *h, int status)
+{
+	struct pppd_compat_pd_t *pd = container_of(h, typeof(*pd), ip_up_hnd);
+	if (conf_verbose) {
+		log_switch(NULL, pd->ppp);
+		log_ppp_debug("pppd_compat: ip-up finished (%i)\n", status);
+	}
+}
+
+static void ip_down_handler(struct sigchld_handler_t *h, int status)
+{
+	struct pppd_compat_pd_t *pd = container_of(h, typeof(*pd), ip_down_hnd);
+	if (conf_verbose) {
+		log_switch(NULL, pd->ppp);
+		log_ppp_debug("pppd_compat: ip-down finished (%i)\n", status);
+	}
+	sched_yield();
+	triton_context_wakeup(pd->ppp->ctrl->ctx);
+}
+
+static void ip_change_handler(struct sigchld_handler_t *h, int status)
+{
+	struct pppd_compat_pd_t *pd = container_of(h, typeof(*pd), ip_change_hnd);
+	if (conf_verbose) {
+		log_switch(NULL, pd->ppp);
+		log_ppp_debug("pppd_compat: ip-change finished (%i)\n", status);
+	}
+	sched_yield();
+	pd->ip_change_res = status;
+	triton_context_wakeup(pd->ppp->ctrl->ctx);
+}
+
+static void ev_ppp_starting(struct ppp_t *ppp)
+{
+	struct pppd_compat_pd_t *pd = malloc(sizeof(*pd));
+
+	if (!pd) {
+		log_emerg("pppd_compat: out of memory\n");
+		return;
+	}
+
+	memset(pd, 0, sizeof(*pd));
+	pd->pd.key = &pd_key;
+	pd->ppp = ppp;
+	pd->ip_up_hnd.handler = ip_up_handler;
+	pd->ip_down_hnd.handler = ip_down_handler;
+	pd->ip_change_hnd.handler = ip_change_handler;
+	list_add_tail(&pd->pd.entry, &ppp->pd_list);
+}
+static void ev_ppp_started(struct ppp_t *ppp)
+{
+	pid_t pid;
+	char *argv[8];
+	char ipaddr[16];
+	char peer_ipaddr[16];
+	struct pppd_compat_pd_t *pd = find_pd(ppp);
+	
+	if (!pd)
+		return;
+
+	argv[4] = ipaddr;
+	argv[5] = peer_ipaddr;
+	fill_argv(argv, ppp, conf_ip_up);
+
+	sigchld_lock();
+	pid = fork();
+	if (pid > 0) {
+		pd->ip_up_hnd.pid = pid;
+		sigchld_register_handler(&pd->ip_up_hnd);
+		if (conf_verbose)
+			log_ppp_debug("pppd_compat: ip-up started (pid %i)\n", pid);
+		sigchld_unlock();
+	} else if (pid == 0) {
+		execv(conf_ip_up, argv);
+		log_error("pppd_compat: exec '%s': %s\n", conf_ip_up, strerror(errno));
+		_exit(EXIT_FAILURE);
+	} else
+		log_error("pppd_compat: fork: %s\n", strerror(errno));
+	
+	pd->started = 1;
+}
+
+static void ev_ppp_finished(struct ppp_t *ppp)
+{
+	pid_t pid;
+	char *argv[8];
+	char ipaddr[16];
+	char peer_ipaddr[16];
+	struct pppd_compat_pd_t *pd = find_pd(ppp);
+	
+	if (!pd)
+		return;
+	
+	if (pd->started) {
+		pthread_mutex_lock(&pd->ip_up_hnd.lock);
+		if (pd->ip_up_hnd.pid) {
+			log_ppp_warn("pppd_compat: ip-up is not yet finished, terminating it ...\n");
+			kill(pd->ip_up_hnd.pid, SIGTERM);
+			pthread_mutex_unlock(&pd->ip_up_hnd.lock);
+		}
+	}
+
+	argv[4] = ipaddr;
+	argv[5] = peer_ipaddr;
+	fill_argv(argv, pd->ppp, conf_ip_down);
+
+	sigchld_lock();
+	pid = fork();
+	if (pid > 0) {
+		pd->ip_down_hnd.pid = pid;
+		sigchld_register_handler(&pd->ip_down_hnd);
+		if (conf_verbose)
+			log_ppp_debug("pppd_compat: ip-down started (pid %i)\n", pid);
+		sigchld_unlock();
+		triton_context_schedule(pd->ppp->ctrl->ctx);
+	} else if (pid == 0) {
+		execv(conf_ip_down, argv);
+		log_error("pppd_compat: exec '%s': %s\n", conf_ip_change, strerror(errno));
+		_exit(EXIT_FAILURE);
+	} else
+		log_error("pppd_compat: fork: %s\n", strerror(errno));
+
+	if (pd->started) {
+		pthread_mutex_lock(&pd->ip_up_hnd.lock);
+		if (pd->ip_up_hnd.pid) {
+			log_ppp_warn("pppd_compat: ip-up is not yet finished, killing it ...\n");
+			kill(pd->ip_up_hnd.pid, SIGKILL);
+			pthread_mutex_unlock(&pd->ip_up_hnd.lock);
+			sigchld_unregister_handler(&pd->ip_up_hnd);
+		} else
+			pthread_mutex_unlock(&pd->ip_up_hnd.lock);
+	}
+
+	if (pd->radattr_saved)
+		remove_radattr(ppp);
+	
+	list_del(&pd->pd.entry);
+	free(pd);
+}
+
+static void ev_radius_access_accept(struct ev_radius_t *ev)
+{
+	struct pppd_compat_pd_t *pd = find_pd(ev->ppp);
+
+	write_radattr(ev->ppp, ev->reply, 0);
+
+	pd->radattr_saved = 1;
+}
+
+static void ev_radius_coa(struct ev_radius_t *ev)
+{
+	pid_t pid;
+	char *argv[8];
+	char ipaddr[16];
+	char peer_ipaddr[16];
+	struct pppd_compat_pd_t *pd = find_pd(ev->ppp);
+	
+	if (!pd)
+		return;
+
+	write_radattr(ev->ppp, ev->request, 1);
+
+	argv[4] = ipaddr;
+	argv[5] = peer_ipaddr;
+	fill_argv(argv, pd->ppp, conf_ip_change);
+
+	sigchld_lock();
+	pid = fork();
+	if (pid > 0) {
+		pd->ip_change_hnd.pid = pid;
+		sigchld_register_handler(&pd->ip_change_hnd);
+		sigchld_unlock();
+		if (conf_verbose)
+			log_ppp_debug("pppd_compat: ip-change started (pid %i)\n", pid);
+		triton_context_schedule(pd->ppp->ctrl->ctx);
+		if (!ev->res)
+			ev->res = pd->ip_change_res;
+	} else if (pid == 0) {
+		execv(conf_ip_change, argv);
+		log_error("pppd_compat: exec '%s': %s\n", conf_ip_change, strerror(errno));
+		_exit(EXIT_FAILURE);
+	} else
+		log_error("pppd_compat: fork: %s\n", strerror(errno));
+}
+
+static void remove_radattr(struct ppp_t *ppp)
+{
+	char *fname;
+
+	fname = malloc(PATH_MAX);
+	if (!fname) {
+		log_emerg("pppd_compat: out of memory\n");
+		return;
+	}
+
+	sprintf(fname, "%s.%s", conf_radattr_prefix, ppp->ifname);
+	if (unlink(fname)) {
+		log_ppp_warn("pppd_compat: failed to remove '%s': %s\n", fname, strerror(errno));
+	}
+	sprintf(fname, "%s_old.%s", conf_radattr_prefix, ppp->ifname);
+	unlink(fname);
+
+	free(fname);
+}
+
+static void write_radattr(struct ppp_t *ppp, struct rad_packet_t *pack, int save_old)
+{
+	struct rad_attr_t *attr;
+	struct rad_dict_value_t *val;
+	FILE *f;
+	char *fname1, *fname2;
+	int i;
+
+	fname1 = malloc(PATH_MAX);
+	if (!fname1) {
+		log_emerg("pppd_compat: out of memory\n");
+		return;
+	}
+
+	if (save_old) {
+		fname2 = malloc(PATH_MAX);
+		if (!fname2) {
+			log_emerg("pppd_compat: out of memory\n");
+			free(fname1);
+			return;
+		}
+	}
+
+	sprintf(fname1, "%s.%s", conf_radattr_prefix, ppp->ifname);
+	if (save_old) {
+		sprintf(fname2, "%s_old.%s", conf_radattr_prefix, ppp->ifname);
+		if (rename(fname1, fname2)) {
+			log_ppp_warn("pppd_compat: rename: %s\n", strerror(errno));
+		}
+	}
+
+	f = fopen(fname1, "w");
+	if (f) {
+		list_for_each_entry(attr, &pack->attrs, entry) {
+			fprintf(f, "%s ", attr->attr->name);
+			switch (attr->attr->type) {
+				case ATTR_TYPE_INTEGER:
+					val = rad_dict_find_val(attr->attr, attr->val);
+					if (val)
+						fprintf(f, "%s\n", val->name);
+					else
+						fprintf(f, "%i\n", attr->val.integer);
+					break;
+				case ATTR_TYPE_STRING:
+					fprintf(f, "%s\n", attr->val.string);
+					break;
+				case ATTR_TYPE_OCTETS:
+					for (i = 0; i < attr->len; i++)
+						fprintf(f, "%02X", attr->val.octets[i]);
+					fprintf(f, "\n");
+					break;
+				case ATTR_TYPE_IPADDR:
+					fprintf(f, "%i.%i.%i.%i\n", attr->val.ipaddr & 0xff, (attr->val.ipaddr >> 8) & 0xff, (attr->val.ipaddr >> 16) & 0xff, (attr->val.ipaddr >> 24) & 0xff);
+					break;
+				case ATTR_TYPE_DATE:
+					fprintf(f, "%lu\n", attr->val.date);
+					break;
+			}
+		}
+		fclose(f);
+	} else
+		log_ppp_warn("pppd_compat: failed to create '%s': %s\n", fname1, strerror(errno));
+	
+	free(fname1);
+	if (save_old)
+		free(fname2);
+}
+
+static struct pppd_compat_pd_t *find_pd(struct ppp_t *ppp)
+{
+	struct ppp_pd_t *pd;
+	struct pppd_compat_pd_t *cpd;
+
+	list_for_each_entry(pd, &ppp->pd_list, entry) {
+		if (pd->key == &pd_key) {
+			cpd = container_of(pd, typeof(*cpd), pd);
+			return cpd;
+		}
+	}
+	
+	log_ppp_warn("pppd_compat: pd not found\n");
+	return NULL;
+}
+
+static void fill_argv(char **argv, struct ppp_t *ppp, char *path)
+{
+	argv[0] = path;
+	argv[1] = ppp->ifname;
+	argv[2] = "none";
+	argv[3] = "0";
+	u_inet_ntoa(ppp->ipaddr, argv[4]);
+	u_inet_ntoa(ppp->peer_ipaddr, argv[5]);
+	argv[6] = "none";
+	argv[7] = NULL;
+}
+
+static void __init init(void)
+{
+	char *opt;
+
+	opt = conf_get_opt("pppd-compat", "ip-up");
+	if (opt)
+		conf_ip_up = opt;
+
+	opt = conf_get_opt("pppd-compat", "ip-down");
+	if (opt)
+		conf_ip_down = opt;
+
+	opt = conf_get_opt("pppd-compat", "ip-change");
+	if (opt)
+		conf_ip_change = opt;
+
+	opt = conf_get_opt("pppd-compat", "radattr-prefix");
+	if (opt)
+		conf_radattr_prefix = opt;
+
+	opt = conf_get_opt("pppd-compat", "verbose");
+	if (opt && atoi(opt) > 0)
+		conf_verbose = 1;
+
+	triton_event_register_handler(EV_PPP_STARTING, (triton_event_func)ev_ppp_starting);
+	triton_event_register_handler(EV_PPP_STARTED, (triton_event_func)ev_ppp_started);
+	triton_event_register_handler(EV_PPP_FINISHED, (triton_event_func)ev_ppp_finished);
+	triton_event_register_handler(EV_RADIUS_ACCESS_ACCEPT, (triton_event_func)ev_radius_access_accept);
+	triton_event_register_handler(EV_RADIUS_COA, (triton_event_func)ev_radius_coa);
+}
+