Function read_proxy_protocol_header

clientname.c:160–310

Try to read a proxy protocol header (V1 or V2). Returns 1 on success or 0 on failure. */

/* Try to read a proxy protocol header (V1 or V2). Returns 1 on success or 0 on failure. */
int read_proxy_protocol_header(int fd)
{
	union {
		struct {
			char line[108];
		} v1;
		struct {
			char sig[PROXY_V2_SIG_SIZE];
			char ver_cmd;
			char fam;
			unsigned char len[2];
			union {
				struct {
					char src_addr[4];
					char dst_addr[4];
					char src_port[2];
					char dst_port[2];
				} ip4;
				struct {
					char src_addr[16];
					char dst_addr[16];
					char src_port[2];
					char dst_port[2];
				} ip6;
				struct {
					char src_addr[108];
					char dst_addr[108];
				} unx;
			} addr;
		} v2;
	} hdr;

	read_buf(fd, (char*)&hdr, PROXY_V2_SIG_SIZE);

	if (memcmp(hdr.v2.sig, proxyv2sig, PROXY_V2_SIG_SIZE) == 0) { /* Proxy V2 */
		int ver, cmd, size;

		read_buf(fd, (char*)&hdr + PROXY_V2_SIG_SIZE, PROXY_V2_HEADER_SIZE - PROXY_V2_SIG_SIZE);

		ver = (hdr.v2.ver_cmd & 0xf0) >> 4;
		cmd = (hdr.v2.ver_cmd & 0x0f);
		size = (hdr.v2.len[0] << 8) + hdr.v2.len[1];

		if (ver != 2 || size + PROXY_V2_HEADER_SIZE > (int)sizeof hdr)
			return 0;

		/* Grab all the remaining data in the binary request. */
		read_buf(fd, (char*)&hdr + PROXY_V2_HEADER_SIZE, size);

		switch (cmd) {
		case CMD_PROXY:
			switch (hdr.v2.fam) {
			case PROXY_FAM_TCPv4:
				if (size != sizeof hdr.v2.addr.ip4)
					return 0;
				inet_ntop(AF_INET, hdr.v2.addr.ip4.src_addr, ipaddr_buf, sizeof ipaddr_buf);
				return valid_ipaddr(ipaddr_buf, False);
#ifdef INET6