1 files changed, 259 insertions, 0 deletions

diff --git a/accel-pppd/ppp/ccp_mppe.c b/accel-pppd/ppp/ccp_mppe.c
new file mode 100644
index 0000000..0952aa0
--- /dev/null
+++ b/accel-pppd/ppp/ccp_mppe.c
@@ -0,0 +1,259 @@
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/socket.h>
+#include <sys/ioctl.h>
+#include "linux_ppp.h"
+
+#include "ppp.h"
+#include "ppp_ccp.h"
+#include "log.h"
+#include "events.h"
+
+#include "memdebug.h"
+
+#define MPPE_H (1 << 24)
+#define MPPE_M (1 << 7)
+#define MPPE_S (1 << 6)
+#define MPPE_L (1 << 5)
+#define MPPE_D (1 << 4)
+#define MPPE_C (1 << 0)
+
+#define MPPE_PAD 4
+
+static struct ccp_option_t *mppe_init(struct ppp_ccp_t *ccp);
+static void mppe_free(struct ppp_ccp_t *ccp, struct ccp_option_t *opt);
+static int mppe_send_conf_req(struct ppp_ccp_t *ccp, struct ccp_option_t *opt, uint8_t *ptr);
+static int mppe_recv_conf_req(struct ppp_ccp_t *ccp, struct ccp_option_t *opt, uint8_t *ptr);
+static int mppe_recv_conf_nak(struct ppp_ccp_t *ccp, struct ccp_option_t *opt, uint8_t *ptr);
+static int mppe_recv_conf_rej(struct ppp_ccp_t *ccp, struct ccp_option_t *opt, uint8_t *ptr);
+static void mppe_print(void (*print)(const char *fmt,...),struct ccp_option_t*, uint8_t *ptr);
+
+struct mppe_option_t
+{
+	struct ccp_option_t opt;
+	int mppe;
+	uint8_t recv_key[16];
+	uint8_t send_key[16];
+	int policy; // 1 - allowed, 2 - required
+};
+
+static struct ccp_option_handler_t mppe_opt_hnd = {
+	.init = mppe_init,
+	.send_conf_req = mppe_send_conf_req,
+	.send_conf_nak = mppe_send_conf_req,
+	.recv_conf_req = mppe_recv_conf_req,
+	.recv_conf_nak = mppe_recv_conf_nak,
+	.recv_conf_rej = mppe_recv_conf_rej,
+	.free = mppe_free,
+	.print = mppe_print,
+};
+
+static struct ccp_option_t *mppe_init(struct ppp_ccp_t *ccp)
+{
+	struct mppe_option_t *mppe_opt = _malloc(sizeof(*mppe_opt));
+	memset(mppe_opt, 0, sizeof(*mppe_opt));
+	mppe_opt->mppe = -1;
+	mppe_opt->opt.id = CI_MPPE;
+	mppe_opt->opt.len = 6;
+
+	return &mppe_opt->opt;
+}
+
+static void mppe_free(struct ppp_ccp_t *ccp, struct ccp_option_t *opt)
+{
+	struct mppe_option_t *mppe_opt = container_of(opt, typeof(*mppe_opt), opt);
+
+	_free(mppe_opt);
+}
+
+static int setup_mppe_key(int fd, int transmit, uint8_t *key)
+{
+	struct ppp_option_data data;
+	uint8_t buf[6 + 16];
+
+	memset(buf, 0, sizeof(buf));
+	buf[0] = CI_MPPE;
+	buf[1] = 6;
+	*(uint32_t*)(buf + 2) = htonl(MPPE_S | MPPE_H);
+	if (key)
+		memcpy(buf + 6, key, 16);
+
+	memset(&data, 0, sizeof(data));
+	data.ptr = buf;
+	data.length = sizeof(buf);
+	data.transmit = transmit;
+
+	if (ioctl(fd, PPPIOCSCOMPRESS, &data)) {
+		log_ppp_warn("mppe: MPPE requested but not supported by kernel\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int decrease_mtu(struct ppp_t *ppp)
+{
+	struct ifreq ifr;
+
+	strcpy(ifr.ifr_name, ppp->ifname);
+
+	if (ioctl(sock_fd, SIOCGIFMTU, &ifr)) {
+		log_ppp_error("mppe: failed to get MTU: %s\n", strerror(errno));
+		return -1;
+	}
+
+	ifr.ifr_mtu -= MPPE_PAD;
+
+	if (ioctl(sock_fd, SIOCSIFMTU, &ifr)) {
+		log_ppp_error("mppe: failed to set MTU: %s\n", strerror(errno));
+		return -1;
+	}
+
+	return 0;
+}
+
+static int mppe_send_conf_req(struct ppp_ccp_t *ccp, struct ccp_option_t *opt, uint8_t *ptr)
+{
+	struct mppe_option_t *mppe_opt = container_of(opt,typeof(*mppe_opt),opt);
+	struct ccp_opt32_t *opt32 = (struct ccp_opt32_t*)ptr;
+
+	if (mppe_opt->mppe != -1)	{
+		opt32->hdr.id = CI_MPPE;
+		opt32->hdr.len = 6;
+		opt32->val = mppe_opt->mppe ? htonl(MPPE_S | MPPE_H) : 0;
+		
+		if (mppe_opt->mppe && setup_mppe_key(ccp->ppp->unit_fd, 0, mppe_opt->recv_key))
+			return 0;
+
+		return 6;
+	}
+	return 0;
+}
+
+static int mppe_recv_conf_req(struct ppp_ccp_t *ccp, struct ccp_option_t *opt, uint8_t *ptr)
+{
+	struct mppe_option_t *mppe_opt = container_of(opt, typeof(*mppe_opt), opt);
+	struct ccp_opt32_t *opt32 = (struct ccp_opt32_t *)ptr;
+
+	/*if (!ptr) {
+		if (mppe_opt->policy == 2)
+			return CCP_OPT_NAK;
+		return CCP_OPT_ACK;
+	}*/
+	
+	if (opt32->hdr.len != 6)
+		return CCP_OPT_REJ;
+
+	if (mppe_opt->policy == 2) {
+		if (ntohl(opt32->val) != (MPPE_S | MPPE_H))
+			return CCP_OPT_NAK;
+	} else if (mppe_opt->policy == 1) {
+		if (ntohl(opt32->val)  == (MPPE_S | MPPE_H))
+			mppe_opt->mppe = 1;
+		else if ((ntohl(opt32->val) & (MPPE_S | MPPE_H)) == (MPPE_S | MPPE_H)) {
+			mppe_opt->mppe = 1;
+			return CCP_OPT_NAK;
+		} else if (opt32->val) {
+			mppe_opt->mppe = 0;
+			return CCP_OPT_NAK;
+		} else
+			mppe_opt->mppe = 0;
+	} else
+		return CCP_OPT_REJ;
+	
+	if (mppe_opt->mppe) {
+		if (setup_mppe_key(ccp->ppp->unit_fd, 1, mppe_opt->send_key))
+			return CCP_OPT_REJ;
+
+		decrease_mtu(ccp->ppp);
+
+		log_ppp_debug(" (mppe enabled)");
+	}
+
+	return CCP_OPT_ACK;
+}
+
+static int mppe_recv_conf_rej(struct ppp_ccp_t *ccp, struct ccp_option_t *opt, uint8_t *ptr)
+{
+	struct mppe_option_t *mppe_opt = container_of(opt, typeof(*mppe_opt), opt);
+
+	if (mppe_opt->mppe != 2) {
+		mppe_opt->mppe = -1;
+		return 0;
+	}
+
+	return -1;
+}
+
+static int mppe_recv_conf_nak(struct ppp_ccp_t *ccp, struct ccp_option_t *opt, uint8_t *ptr)
+{
+	struct mppe_option_t *mppe_opt = container_of(opt, typeof(*mppe_opt), opt);
+	struct ccp_opt32_t *opt32 = (struct ccp_opt32_t *)ptr;
+
+	if (opt32->hdr.len != 6)
+		return -1;
+
+	if (mppe_opt->policy == 2) {
+		if (ntohl(opt32->val) == (MPPE_S | MPPE_H))
+			return -1;
+	} else if (mppe_opt->policy == 1) {
+		if ((ntohl(opt32->val) & (MPPE_S | MPPE_H)) == (MPPE_S | MPPE_H))
+			mppe_opt->mppe = 0;
+		else
+			mppe_opt->mppe = 1;
+	} else {
+		if (opt32->val == 0)
+			return -1;
+	}
+
+	return 0;
+}
+
+static void mppe_print(void (*print)(const char *fmt,...),struct ccp_option_t *opt, uint8_t *ptr)
+{
+	struct mppe_option_t *mppe_opt = container_of(opt, typeof(*mppe_opt), opt);
+	struct ccp_opt32_t *opt32 = (struct ccp_opt32_t *)ptr;
+	uint32_t bits;
+
+	if (ptr)
+		bits = ntohl(opt32->val);
+	else
+		if (mppe_opt->mppe)
+			bits = MPPE_S | MPPE_H;
+		else
+			bits = 0;
+
+	print("<mppe %sH %sM %sS %sL %sD %sC>",
+		bits & MPPE_H ? "+" : "-",
+		bits & MPPE_M ? "+" : "-",
+		bits & MPPE_S ? "+" : "-",
+		bits & MPPE_L ? "+" : "-",
+		bits & MPPE_D ? "+" : "-",
+		bits & MPPE_C ? "+" : "-" 
+	);
+}
+
+static void ev_mppe_keys(struct ev_mppe_keys_t *ev)
+{
+	struct mppe_option_t *mppe_opt = container_of(ccp_find_option(ev->ppp, &mppe_opt_hnd), typeof(*mppe_opt), opt);
+
+	if ((ev->type & 0x04) == 0) {
+		log_ppp_warn("mppe: 128-bit session keys not allowed, disabling mppe ...\n");
+		return;
+	}
+	
+	memcpy(mppe_opt->recv_key, ev->recv_key, 16);
+	memcpy(mppe_opt->send_key, ev->send_key, 16);
+	mppe_opt->policy = ev->policy;
+
+	if (ev->policy == 2)
+		mppe_opt->mppe = 1;
+}
+
+static void __init mppe_opt_init()
+{
+	ccp_option_register(&mppe_opt_hnd);
+	triton_event_register_handler(EV_MPPE_KEYS, (triton_event_func)ev_mppe_keys);
+}
+