From: Anton Ivanov <anton.iva...@cambridgegreys.com>
Migrate L2TPv3 transport to the Unified Datagram Socket
Transport Backend.
Signed-off-by: Anton Ivanov <anton.iva...@cambridgegreys.com>
---
net/l2tpv3.c | 537 +++++++++--------------------------------------------------
1 file changed, 83 insertions(+), 454 deletions(-)
diff --git a/net/l2tpv3.c b/net/l2tpv3.c
index 6745b78990..25b7628244 100644
--- a/net/l2tpv3.c
+++ b/net/l2tpv3.c
@@ -1,6 +1,7 @@
/*
* QEMU System Emulator
*
+ * Copyright (c) 2015-2017 Cambridge Greys Limited
* Copyright (c) 2003-2008 Fabrice Bellard
* Copyright (c) 2012-2014 Cisco Systems
*
@@ -30,23 +31,14 @@
#include "clients.h"
#include "qemu-common.h"
#include "qemu/error-report.h"
+#include "qapi/error.h"
#include "qemu/option.h"
#include "qemu/sockets.h"
#include "qemu/iov.h"
#include "qemu/main-loop.h"
+#include "udst.h"
-/* The buffer size needs to be investigated for optimum numbers and
- * optimum means of paging in on different systems. This size is
- * chosen to be sufficient to accommodate one packet with some headers
- */
-
-#define BUFFER_ALIGN sysconf(_SC_PAGESIZE)
-#define BUFFER_SIZE 2048
-#define IOVSIZE 2
-#define MAX_L2TPV3_MSGCNT 64
-#define MAX_L2TPV3_IOVCNT (MAX_L2TPV3_MSGCNT * IOVSIZE)
-
/* Header set to 0x30000 signifies a data packet */
#define L2TPV3_DATA_PACKET 0x30000
@@ -57,31 +49,7 @@
#define IPPROTO_L2TP 0x73
#endif
-typedef struct NetL2TPV3State {
- NetClientState nc;
- int fd;
-
- /*
- * these are used for xmit - that happens packet a time
- * and for first sign of life packet (easier to parse that once)
- */
-
- uint8_t *header_buf;
- struct iovec *vec;
-
- /*
- * these are used for receive - try to "eat" up to 32 packets at a time
- */
-
- struct mmsghdr *msgvec;
-
- /*
- * peer address
- */
-
- struct sockaddr_storage *dgram_dst;
- uint32_t dst_size;
-
+typedef struct L2TPV3TunnelParams {
/*
* L2TPv3 parameters
*/
@@ -90,37 +58,8 @@ typedef struct NetL2TPV3State {
uint64_t tx_cookie;
uint32_t rx_session;
uint32_t tx_session;
- uint32_t header_size;
uint32_t counter;
- /*
- * DOS avoidance in error handling
- */
-
- bool header_mismatch;
-
- /*
- * Ring buffer handling
- */
-
- int queue_head;
- int queue_tail;
- int queue_depth;
-
- /*
- * Precomputed offsets
- */
-
- uint32_t offset;
- uint32_t cookie_offset;
- uint32_t counter_offset;
- uint32_t session_offset;
-
- /* Poll Control */
-
- bool read_poll;
- bool write_poll;
-
/* Flags */
bool ipv6;
@@ -130,189 +69,62 @@ typedef struct NetL2TPV3State {
bool cookie;
bool cookie_is_64;
-} NetL2TPV3State;
-
-static void net_l2tpv3_send(void *opaque);
-static void l2tpv3_writable(void *opaque);
-
-static void l2tpv3_update_fd_handler(NetL2TPV3State *s)
-{
- qemu_set_fd_handler(s->fd,
- s->read_poll ? net_l2tpv3_send : NULL,
- s->write_poll ? l2tpv3_writable : NULL,
- s);
-}
-
-static void l2tpv3_read_poll(NetL2TPV3State *s, bool enable)
-{
- if (s->read_poll != enable) {
- s->read_poll = enable;
- l2tpv3_update_fd_handler(s);
- }
-}
+ /* Precomputed L2TPV3 specific offsets */
+ uint32_t cookie_offset;
+ uint32_t counter_offset;
+ uint32_t session_offset;
-static void l2tpv3_write_poll(NetL2TPV3State *s, bool enable)
-{
- if (s->write_poll != enable) {
- s->write_poll = enable;
- l2tpv3_update_fd_handler(s);
- }
-}
+} L2TPV3TunnelParams;
-static void l2tpv3_writable(void *opaque)
-{
- NetL2TPV3State *s = opaque;
- l2tpv3_write_poll(s, false);
- qemu_flush_queued_packets(&s->nc);
-}
-static void l2tpv3_send_completed(NetClientState *nc, ssize_t len)
-{
- NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
- l2tpv3_read_poll(s, true);
-}
-static void l2tpv3_poll(NetClientState *nc, bool enable)
+static void l2tpv3_form_header(void *us)
{
- NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
- l2tpv3_write_poll(s, enable);
- l2tpv3_read_poll(s, enable);
-}
+ NetUdstState *s = (NetUdstState *) us;
+ L2TPV3TunnelParams *p = (L2TPV3TunnelParams *) s->params;
-static void l2tpv3_form_header(NetL2TPV3State *s)
-{
uint32_t *counter;
- if (s->udp) {
+ if (p->udp) {
stl_be_p((uint32_t *) s->header_buf, L2TPV3_DATA_PACKET);
}
stl_be_p(
- (uint32_t *) (s->header_buf + s->session_offset),
- s->tx_session
+ (uint32_t *) (s->header_buf + p->session_offset),
+ p->tx_session
);
- if (s->cookie) {
- if (s->cookie_is_64) {
+ if (p->cookie) {
+ if (p->cookie_is_64) {
stq_be_p(
- (uint64_t *)(s->header_buf + s->cookie_offset),
- s->tx_cookie
+ (uint64_t *)(s->header_buf + p->cookie_offset),
+ p->tx_cookie
);
} else {
stl_be_p(
- (uint32_t *) (s->header_buf + s->cookie_offset),
- s->tx_cookie
+ (uint32_t *) (s->header_buf + p->cookie_offset),
+ p->tx_cookie
);
}
}
- if (s->has_counter) {
- counter = (uint32_t *)(s->header_buf + s->counter_offset);
- if (s->pin_counter) {
+ if (p->has_counter) {
+ counter = (uint32_t *)(s->header_buf + p->counter_offset);
+ if (p->pin_counter) {
*counter = 0;
} else {
- stl_be_p(counter, ++s->counter);
+ stl_be_p(counter, ++p->counter);
}
}
}
-static ssize_t net_l2tpv3_receive_dgram_iov(NetClientState *nc,
- const struct iovec *iov,
- int iovcnt)
-{
- NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
- struct msghdr message;
- int ret;
-
- if (iovcnt > MAX_L2TPV3_IOVCNT - 1) {
- error_report(
- "iovec too long %d > %d, change l2tpv3.h",
- iovcnt, MAX_L2TPV3_IOVCNT
- );
- return -1;
- }
- l2tpv3_form_header(s);
- memcpy(s->vec + 1, iov, iovcnt * sizeof(struct iovec));
- s->vec->iov_base = s->header_buf;
- s->vec->iov_len = s->offset;
- message.msg_name = s->dgram_dst;
- message.msg_namelen = s->dst_size;
- message.msg_iov = s->vec;
- message.msg_iovlen = iovcnt + 1;
- message.msg_control = NULL;
- message.msg_controllen = 0;
- message.msg_flags = 0;
- do {
- ret = sendmsg(s->fd, &message, 0);
- } while ((ret == -1) && (errno == EINTR));
- if (ret > 0) {
- ret -= s->offset;
- } else if (ret == 0) {
- /* belt and braces - should not occur on DGRAM
- * we should get an error and never a 0 send
- */
- ret = iov_size(iov, iovcnt);
- } else {
- /* signal upper layer that socket buffer is full */
- ret = -errno;
- if (ret == -EAGAIN || ret == -ENOBUFS) {
- l2tpv3_write_poll(s, true);
- ret = 0;
- }
- }
- return ret;
-}
-
-static ssize_t net_l2tpv3_receive_dgram(NetClientState *nc,
- const uint8_t *buf,
- size_t size)
-{
- NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
-
- struct iovec *vec;
- struct msghdr message;
- ssize_t ret = 0;
-
- l2tpv3_form_header(s);
- vec = s->vec;
- vec->iov_base = s->header_buf;
- vec->iov_len = s->offset;
- vec++;
- vec->iov_base = (void *) buf;
- vec->iov_len = size;
- message.msg_name = s->dgram_dst;
- message.msg_namelen = s->dst_size;
- message.msg_iov = s->vec;
- message.msg_iovlen = 2;
- message.msg_control = NULL;
- message.msg_controllen = 0;
- message.msg_flags = 0;
- do {
- ret = sendmsg(s->fd, &message, 0);
- } while ((ret == -1) && (errno == EINTR));
- if (ret > 0) {
- ret -= s->offset;
- } else if (ret == 0) {
- /* belt and braces - should not occur on DGRAM
- * we should get an error and never a 0 send
- */
- ret = size;
- } else {
- ret = -errno;
- if (ret == -EAGAIN || ret == -ENOBUFS) {
- /* signal upper layer that socket buffer is full */
- l2tpv3_write_poll(s, true);
- ret = 0;
- }
- }
- return ret;
-}
-
-static int l2tpv3_verify_header(NetL2TPV3State *s, uint8_t *buf)
+static int l2tpv3_verify_header(void *us, uint8_t *buf)
{
+ NetUdstState *s = (NetUdstState *) us;
+ L2TPV3TunnelParams *p = (L2TPV3TunnelParams *) s->params;
uint32_t *session;
uint64_t cookie;
- if ((!s->udp) && (!s->ipv6)) {
+ if ((!p->udp) && (!p->ipv6)) {
buf += sizeof(struct iphdr) /* fix for ipv4 raw */;
}
@@ -321,21 +133,21 @@ static int l2tpv3_verify_header(NetL2TPV3State *s,
uint8_t *buf)
* that anyway.
*/
- if (s->cookie) {
- if (s->cookie_is_64) {
- cookie = ldq_be_p(buf + s->cookie_offset);
+ if (p->cookie) {
+ if (p->cookie_is_64) {
+ cookie = ldq_be_p(buf + p->cookie_offset);
} else {
- cookie = ldl_be_p(buf + s->cookie_offset) & 0xffffffffULL;
+ cookie = ldl_be_p(buf + p->cookie_offset) & 0xffffffffULL;
}
- if (cookie != s->rx_cookie) {
+ if (cookie != p->rx_cookie) {
if (!s->header_mismatch) {
error_report("unknown cookie id");
}
return -1;
}
}
- session = (uint32_t *) (buf + s->session_offset);
- if (ldl_be_p(session) != s->rx_session) {
+ session = (uint32_t *) (buf + p->session_offset);
+ if (ldl_be_p(session) != p->rx_session) {
if (!s->header_mismatch) {
error_report("session mismatch");
}
@@ -344,214 +156,35 @@ static int l2tpv3_verify_header(NetL2TPV3State *s,
uint8_t *buf)
return 0;
}
-static void net_l2tpv3_process_queue(NetL2TPV3State *s)
-{
- int size = 0;
- struct iovec *vec;
- bool bad_read;
- int data_size;
- struct mmsghdr *msgvec;
-
- /* go into ring mode only if there is a "pending" tail */
- if (s->queue_depth > 0) {
- do {
- msgvec = s->msgvec + s->queue_tail;
- if (msgvec->msg_len > 0) {
- data_size = msgvec->msg_len - s->header_size;
- vec = msgvec->msg_hdr.msg_iov;
- if ((data_size > 0) &&
- (l2tpv3_verify_header(s, vec->iov_base) == 0)) {
- vec++;
- /* Use the legacy delivery for now, we will
- * switch to using our own ring as a queueing mechanism
- * at a later date
- */
- size = qemu_send_packet_async(
- &s->nc,
- vec->iov_base,
- data_size,
- l2tpv3_send_completed
- );
- if (size == 0) {
- l2tpv3_read_poll(s, false);
- }
- bad_read = false;
- } else {
- bad_read = true;
- if (!s->header_mismatch) {
- /* report error only once */
- error_report("l2tpv3 header verification failed");
- s->header_mismatch = true;
- }
- }
- } else {
- bad_read = true;
- }
- s->queue_tail = (s->queue_tail + 1) % MAX_L2TPV3_MSGCNT;
- s->queue_depth--;
- } while (
- (s->queue_depth > 0) &&
- qemu_can_send_packet(&s->nc) &&
- ((size > 0) || bad_read)
- );
- }
-}
-
-static void net_l2tpv3_send(void *opaque)
-{
- NetL2TPV3State *s = opaque;
- int target_count, count;
- struct mmsghdr *msgvec;
-
- /* go into ring mode only if there is a "pending" tail */
-
- if (s->queue_depth) {
-
- /* The ring buffer we use has variable intake
- * count of how much we can read varies - adjust accordingly
- */
-
- target_count = MAX_L2TPV3_MSGCNT - s->queue_depth;
-
- /* Ensure we do not overrun the ring when we have
- * a lot of enqueued packets
- */
-
- if (s->queue_head + target_count > MAX_L2TPV3_MSGCNT) {
- target_count = MAX_L2TPV3_MSGCNT - s->queue_head;
- }
- } else {
-
- /* we do not have any pending packets - we can use
- * the whole message vector linearly instead of using
- * it as a ring
- */
-
- s->queue_head = 0;
- s->queue_tail = 0;
- target_count = MAX_L2TPV3_MSGCNT;
- }
-
- msgvec = s->msgvec + s->queue_head;
- if (target_count > 0) {
- do {
- count = recvmmsg(
- s->fd,
- msgvec,
- target_count, MSG_DONTWAIT, NULL);
- } while ((count == -1) && (errno == EINTR));
- if (count < 0) {
- /* Recv error - we still need to flush packets here,
- * (re)set queue head to current position
- */
- count = 0;
- }
- s->queue_head = (s->queue_head + count) % MAX_L2TPV3_MSGCNT;
- s->queue_depth += count;
- }
- net_l2tpv3_process_queue(s);
-}
-
-static void destroy_vector(struct mmsghdr *msgvec, int count, int iovcount)
-{
- int i, j;
- struct iovec *iov;
- struct mmsghdr *cleanup = msgvec;
- if (cleanup) {
- for (i = 0; i < count; i++) {
- if (cleanup->msg_hdr.msg_iov) {
- iov = cleanup->msg_hdr.msg_iov;
- for (j = 0; j < iovcount; j++) {
- g_free(iov->iov_base);
- iov++;
- }
- g_free(cleanup->msg_hdr.msg_iov);
- }
- cleanup++;
- }
- g_free(msgvec);
- }
-}
-
-static struct mmsghdr *build_l2tpv3_vector(NetL2TPV3State *s, int count)
-{
- int i;
- struct iovec *iov;
- struct mmsghdr *msgvec, *result;
-
- msgvec = g_new(struct mmsghdr, count);
- result = msgvec;
- for (i = 0; i < count ; i++) {
- msgvec->msg_hdr.msg_name = NULL;
- msgvec->msg_hdr.msg_namelen = 0;
- iov = g_new(struct iovec, IOVSIZE);
- msgvec->msg_hdr.msg_iov = iov;
- iov->iov_base = g_malloc(s->header_size);
- iov->iov_len = s->header_size;
- iov++ ;
- iov->iov_base = qemu_memalign(BUFFER_ALIGN, BUFFER_SIZE);
- iov->iov_len = BUFFER_SIZE;
- msgvec->msg_hdr.msg_iovlen = 2;
- msgvec->msg_hdr.msg_control = NULL;
- msgvec->msg_hdr.msg_controllen = 0;
- msgvec->msg_hdr.msg_flags = 0;
- msgvec++;
- }
- return result;
-}
-
-static void net_l2tpv3_cleanup(NetClientState *nc)
-{
- NetL2TPV3State *s = DO_UPCAST(NetL2TPV3State, nc, nc);
- qemu_purge_queued_packets(nc);
- l2tpv3_read_poll(s, false);
- l2tpv3_write_poll(s, false);
- if (s->fd >= 0) {
- close(s->fd);
- }
- destroy_vector(s->msgvec, MAX_L2TPV3_MSGCNT, IOVSIZE);
- g_free(s->vec);
- g_free(s->header_buf);
- g_free(s->dgram_dst);
-}
-
-static NetClientInfo net_l2tpv3_info = {
- .type = NET_CLIENT_DRIVER_L2TPV3,
- .size = sizeof(NetL2TPV3State),
- .receive = net_l2tpv3_receive_dgram,
- .receive_iov = net_l2tpv3_receive_dgram_iov,
- .poll = l2tpv3_poll,
- .cleanup = net_l2tpv3_cleanup,
-};
-
int net_init_l2tpv3(const Netdev *netdev,
const char *name,
NetClientState *peer, Error **errp)
{
- /* FIXME error_setg(errp, ...) on failure */
const NetdevL2TPv3Options *l2tpv3;
- NetL2TPV3State *s;
+ NetUdstState *s;
NetClientState *nc;
+ L2TPV3TunnelParams *p;
+
int fd = -1, gairet;
struct addrinfo hints;
struct addrinfo *result = NULL;
char *srcport, *dstport;
- nc = qemu_new_net_client(&net_l2tpv3_info, peer, "l2tpv3", name);
+ nc = qemu_new_udst_net_client(name, peer);
+
+ s = DO_UPCAST(NetUdstState, nc, nc);
- s = DO_UPCAST(NetL2TPV3State, nc, nc);
+ p = g_malloc(sizeof(L2TPV3TunnelParams));
- s->queue_head = 0;
- s->queue_tail = 0;
- s->header_mismatch = false;
+ s->params = p;
assert(netdev->type == NET_CLIENT_DRIVER_L2TPV3);
l2tpv3 = &netdev->u.l2tpv3;
if (l2tpv3->has_ipv6 && l2tpv3->ipv6) {
- s->ipv6 = l2tpv3->ipv6;
+ p->ipv6 = l2tpv3->ipv6;
} else {
- s->ipv6 = false;
+ p->ipv6 = false;
}
if ((l2tpv3->has_offset) && (l2tpv3->offset > 256)) {
@@ -561,22 +194,22 @@ int net_init_l2tpv3(const Netdev *netdev,
if (l2tpv3->has_rxcookie || l2tpv3->has_txcookie) {
if (l2tpv3->has_rxcookie && l2tpv3->has_txcookie) {
- s->cookie = true;
+ p->cookie = true;
} else {
goto outerr;
}
} else {
- s->cookie = false;
+ p->cookie = false;
}
if (l2tpv3->has_cookie64 || l2tpv3->cookie64) {
- s->cookie_is_64 = true;
+ p->cookie_is_64 = true;
} else {
- s->cookie_is_64 = false;
+ p->cookie_is_64 = false;
}
if (l2tpv3->has_udp && l2tpv3->udp) {
- s->udp = true;
+ p->udp = true;
if (!(l2tpv3->has_srcport && l2tpv3->has_dstport)) {
error_report("l2tpv3_open : need both src and dst port for udp");
goto outerr;
@@ -585,52 +218,52 @@ int net_init_l2tpv3(const Netdev *netdev,
dstport = l2tpv3->dstport;
}
} else {
- s->udp = false;
+ p->udp = false;
srcport = NULL;
dstport = NULL;
}
s->offset = 4;
- s->session_offset = 0;
- s->cookie_offset = 4;
- s->counter_offset = 4;
+ p->session_offset = 0;
+ p->cookie_offset = 4;
+ p->counter_offset = 4;
- s->tx_session = l2tpv3->txsession;
+ p->tx_session = l2tpv3->txsession;
if (l2tpv3->has_rxsession) {
- s->rx_session = l2tpv3->rxsession;
+ p->rx_session = l2tpv3->rxsession;
} else {
- s->rx_session = s->tx_session;
+ p->rx_session = p->tx_session;
}
- if (s->cookie) {
- s->rx_cookie = l2tpv3->rxcookie;
- s->tx_cookie = l2tpv3->txcookie;
- if (s->cookie_is_64 == true) {
+ if (p->cookie) {
+ p->rx_cookie = l2tpv3->rxcookie;
+ p->tx_cookie = l2tpv3->txcookie;
+ if (p->cookie_is_64 == true) {
/* 64 bit cookie */
s->offset += 8;
- s->counter_offset += 8;
+ p->counter_offset += 8;
} else {
/* 32 bit cookie */
s->offset += 4;
- s->counter_offset += 4;
+ p->counter_offset += 4;
}
}
memset(&hints, 0, sizeof(hints));
- if (s->ipv6) {
+ if (p->ipv6) {
hints.ai_family = AF_INET6;
} else {
hints.ai_family = AF_INET;
}
- if (s->udp) {
+ if (p->udp) {
hints.ai_socktype = SOCK_DGRAM;
hints.ai_protocol = 0;
s->offset += 4;
- s->counter_offset += 4;
- s->session_offset += 4;
- s->cookie_offset += 4;
+ p->counter_offset += 4;
+ p->session_offset += 4;
+ p->cookie_offset += 4;
} else {
hints.ai_socktype = SOCK_RAW;
hints.ai_protocol = IPPROTO_L2TP;
@@ -661,12 +294,12 @@ int net_init_l2tpv3(const Netdev *netdev,
memset(&hints, 0, sizeof(hints));
- if (s->ipv6) {
+ if (p->ipv6) {
hints.ai_family = AF_INET6;
} else {
hints.ai_family = AF_INET;
}
- if (s->udp) {
+ if (p->udp) {
hints.ai_socktype = SOCK_DGRAM;
hints.ai_protocol = 0;
} else {
@@ -693,17 +326,17 @@ int net_init_l2tpv3(const Netdev *netdev,
}
if (l2tpv3->has_counter && l2tpv3->counter) {
- s->has_counter = true;
+ p->has_counter = true;
s->offset += 4;
} else {
- s->has_counter = false;
+ p->has_counter = false;
}
if (l2tpv3->has_pincounter && l2tpv3->pincounter) {
- s->has_counter = true; /* pin counter implies that there is counter */
- s->pin_counter = true;
+ p->has_counter = true; /* pin counter implies that there is counter */
+ p->pin_counter = true;
} else {
- s->pin_counter = false;
+ p->pin_counter = false;
}
if (l2tpv3->has_offset) {
@@ -711,27 +344,23 @@ int net_init_l2tpv3(const Netdev *netdev,
s->offset += l2tpv3->offset;
}
- if ((s->ipv6) || (s->udp)) {
+ if ((p->ipv6) || (p->udp)) {
s->header_size = s->offset;
} else {
s->header_size = s->offset + sizeof(struct iphdr);
}
- s->msgvec = build_l2tpv3_vector(s, MAX_L2TPV3_MSGCNT);
- s->vec = g_new(struct iovec, MAX_L2TPV3_IOVCNT);
- s->header_buf = g_malloc(s->header_size);
-
- qemu_set_nonblock(fd);
-
- s->fd = fd;
- s->counter = 0;
-
- l2tpv3_read_poll(s, true);
+ qemu_net_finalize_udst_init(s,
+ &l2tpv3_verify_header,
+ &l2tpv3_form_header,
+ fd);
+ p->counter = 0;
snprintf(s->nc.info_str, sizeof(s->nc.info_str),
"l2tpv3: connected");
return 0;
outerr:
+ error_setg(errp, "Cannot initialize L2TPv3 transport");
qemu_del_net_client(nc);
if (fd >= 0) {
close(fd);
--
2.11.0
