Adding upstream version 9.1.upstream/9.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 190 insertions, 0 deletions

diff --git a/vrrpd/vrrp_packet.h b/vrrpd/vrrp_packet.h
new file mode 100644
index 0000000..99136da
--- /dev/null
+++ b/vrrpd/vrrp_packet.h
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * VRRP packet crafting.
+ * Copyright (C) 2018-2019 Cumulus Networks, Inc.
+ * Quentin Young
+ */
+#ifndef __VRRP_PACKET_H__
+#define __VRRP_PACKET_H__
+
+#include <zebra.h>
+
+#include "lib/ipaddr.h"
+#include "lib/memory.h"
+#include "lib/prefix.h"
+
+#define VRRP_TYPE_ADVERTISEMENT 1
+
+/*
+ * Shared header for VRRPv2/v3 packets.
+ */
+struct vrrp_hdr {
+	/*
+	 * H  L H  L
+	 * 0000 0000
+	 * ver  type
+	 */
+	uint8_t vertype;
+	uint8_t vrid;
+	uint8_t priority;
+	uint8_t naddr;
+	union {
+		struct {
+			uint8_t auth_type;
+			/* advertisement interval (in sec) */
+			uint8_t adver_int;
+		} v2;
+		struct {
+			/*
+			 * advertisement interval (in centiseconds)
+			 * H  L H          L
+			 * 0000 000000000000
+			 * rsvd adver_int
+			 */
+			uint16_t adver_int;
+		} v3;
+	};
+	uint16_t chksum;
+} __attribute__((packed));
+
+#define VRRP_HDR_SIZE sizeof(struct vrrp_hdr)
+
+struct vrrp_pkt {
+	struct vrrp_hdr hdr;
+	/*
+	 * When used, this is actually an array of one or the other, not an
+	 * array of union. If N v4 addresses are stored then
+	 * sizeof(addrs) == N * sizeof(struct in_addr).
+	 *
+	 * Under v2, the last 2 entries in this array are the authentication
+	 * data fields. We don't support auth in v2 so these are always just 8
+	 * bytes of 0x00.
+	 */
+	union {
+		struct in_addr v4;
+		struct in6_addr v6;
+	} addrs[];
+} __attribute__((packed));
+
+#define VRRP_PKT_SIZE(_f, _ver, _naddr)                                        \
+	({                                                                     \
+		size_t _asz = ((_f) == AF_INET) ? sizeof(struct in_addr)       \
+						: sizeof(struct in6_addr);     \
+		size_t _auth = 2 * sizeof(uint32_t) * (3 - (_ver));            \
+		sizeof(struct vrrp_hdr) + (_asz * (_naddr)) + _auth;           \
+	})
+
+#define VRRP_MIN_PKT_SIZE_V4 VRRP_PKT_SIZE(AF_INET, 3, 1)
+#define VRRP_MAX_PKT_SIZE_V4 VRRP_PKT_SIZE(AF_INET, 2, 255)
+#define VRRP_MIN_PKT_SIZE_V6 VRRP_PKT_SIZE(AF_INET6, 3, 1)
+#define VRRP_MAX_PKT_SIZE_V6 VRRP_PKT_SIZE(AF_INET6, 3, 255)
+
+#define VRRP_MIN_PKT_SIZE VRRP_MIN_PKT_SIZE_V4
+#define VRRP_MAX_PKT_SIZE VRRP_MAX_PKT_SIZE_V6
+
+/*
+ * Builds a VRRP ADVERTISEMENT packet.
+ *
+ * pkt
+ *    Pointer to store pointer to result buffer in
+ *
+ * src
+ *    Source address packet will be transmitted from. This is needed to compute
+ *    the VRRP checksum. The returned packet must be sent in an IP datagram with
+ *    the source address equal to this field, or the checksum will be invalid.
+ *
+ * version
+ *    VRRP version; must be 2 or 3
+ *
+ * vrid
+ *    Virtual Router Identifier
+ *
+ * prio
+ *    Virtual Router Priority
+ *
+ * max_adver_int
+ *    time between ADVERTISEMENTs
+ *
+ * v6
+ *    whether 'ips' is an array of v4 or v6 addresses
+ *
+ * numip
+ *    number of IPvX addresses in 'ips'
+ *
+ * ips
+ *    array of pointer to either struct in_addr (v6 = false) or struct in6_addr
+ *    (v6 = true)
+ */
+ssize_t vrrp_pkt_adver_build(struct vrrp_pkt **pkt, struct ipaddr *src,
+			     uint8_t version, uint8_t vrid, uint8_t prio,
+			     uint16_t max_adver_int, uint8_t numip,
+			     struct ipaddr **ips, bool ipv4_ph);
+
+/* free memory allocated by vrrp_pkt_adver_build's pkt arg */
+void vrrp_pkt_free(struct vrrp_pkt *pkt);
+
+/*
+ * Dumps a VRRP ADVERTISEMENT packet to a string.
+ *
+ * Currently only dumps the header.
+ *
+ * buf
+ *    Buffer to store string representation
+ *
+ * buflen
+ *    Size of buf
+ *
+ * pkt
+ *    Packet to dump to a string
+ *
+ * Returns:
+ *    # bytes written to buf
+ */
+size_t vrrp_pkt_adver_dump(char *buf, size_t buflen, struct vrrp_pkt *pkt);
+
+
+/*
+ * Parses a VRRP packet, checking for illegal or invalid data.
+ *
+ * This function parses both VRRPv2 and VRRPv3 packets. Which version is
+ * expected is determined by the version argument. For example, if version is 3
+ * and the received packet has version field 2 it will fail to parse.
+ *
+ * Note that this function only checks whether the packet itself is a valid
+ * VRRP packet. It is up to the caller to validate whether the VRID is correct,
+ * priority and timer values are correct, etc.
+ *
+ * family
+ *    Address family of received packet
+ *
+ * version
+ *   VRRP version to use for validation
+ *
+ * m
+ *    msghdr containing results of recvmsg() on VRRP router socket
+ *
+ * read
+ *    Return value of recvmsg() on VRRP router socket; must be non-negative
+ *
+ * src
+ *    Pointer to struct ipaddr to store address of datagram sender
+ *
+ * pkt
+ *    Pointer to pointer to set to location of VRRP packet within buf
+ *
+ * errmsg
+ *    Buffer to store human-readable error message in case of error; may be
+ *    NULL, in which case no message will be stored
+ *
+ * errmsg_len
+ *    Size of errmsg
+ *
+ * Returns:
+ *    Size of VRRP packet, or -1 upon error
+ */
+ssize_t vrrp_pkt_parse_datagram(int family, int version, bool ipv4_ph,
+				struct msghdr *m, size_t read,
+				struct ipaddr *src, struct vrrp_pkt **pkt,
+				char *errmsg, size_t errmsg_len);
+
+#endif /* __VRRP_PACKET_H__ */