- Merge #881: Generalise the proxy protocol code.

gthess · gthess · commit 13d4504dfcd2 · 2023-10-03T14:51:50.000+02:00
diff --git a/daemon/worker.c b/daemon/worker.c
@@ -66,6 +66,7 @@
 #include "util/data/msgencode.h"
 #include "util/data/dname.h"
 #include "util/fptr_wlist.h"
+#include "util/proxy_protocol.h"
 #include "util/tube.h"
 #include "util/edns.h"
 #include "util/timeval_func.h"
@@ -2317,6 +2318,7 @@ worker_init(struct worker* worker, struct config_file *cfg,
 			worker->env.cfg->stat_interval);
 		worker_restart_timer(worker);
 	}
+	pp_init(&sldns_write_uint16, &sldns_write_uint32);
 	return 1;
 }
 
diff --git a/doc/Changelog b/doc/Changelog
@@ -1,3 +1,6 @@
+3 October 2023: George
+	- Merge #881: Generalise the proxy protocol code.
+
 2 October 2023: George
 	- Fix misplaced comment.
 
diff --git a/libunbound/libworker.c b/libunbound/libworker.c
@@ -62,6 +62,7 @@
 #include "util/random.h"
 #include "util/config_file.h"
 #include "util/netevent.h"
+#include "util/proxy_protocol.h"
 #include "util/storage/lookup3.h"
 #include "util/storage/slabhash.h"
 #include "util/net_help.h"
@@ -265,6 +266,7 @@ libworker_setup(struct ub_ctx* ctx, int is_bg, struct ub_event_base* eb)
 	w->env->kill_sub = &mesh_state_delete;
 	w->env->detect_cycle = &mesh_detect_cycle;
 	comm_base_timept(w->base, &w->env->now, &w->env->now_tv);
+	pp_init(&sldns_write_uint16, &sldns_write_uint32);
 	return w;
 }
 
diff --git a/testcode/streamtcp.1 b/testcode/streamtcp.1
@@ -61,6 +61,17 @@ Specify the server to send the queries to. If not specified localhost (127.0.0.1
 .B \-d \fIsecs
 Delay after the connection before sending query.  This tests the timeout
 on the other side, eg. if shorter the connection is closed.
+.TP
+.B \-p \fIclient
+Use proxy protocol to send the query. Specify the ipaddr@portnr of the client
+to include in PROXYv2.
+.TP
+.B IXFR=serial
+Pass the type of the query as IXFR=N to send an IXFR query with serial N.
+.TP
+.B NOTIFY[=serial]
+Pass the type of the query as NOTIFY[=N] to send a notify packet. The serial N
+of the new zone can be included.
 .SH "EXAMPLES"
 .LP
 Some examples of use.
diff --git a/testcode/streamtcp.c b/testcode/streamtcp.c
@@ -79,6 +79,8 @@ static void usage(char* argv[])
 	printf("-d secs		delay after connection before sending query\n");
 	printf("-s		use ssl\n");
 	printf("-h 		this help text\n");
+	printf("IXFR=N 		for the type, sends ixfr query with serial N.\n");
+	printf("NOTIFY[=N] 	for the type, sends notify. Can set new zone serial N.\n");
 	exit(1);
 }
 
@@ -115,6 +117,29 @@ open_svr(const char* svr, int udp, struct sockaddr_storage* addr,
 	return fd;
 }
 
+/** Append a SOA record with serial number */
+static void
+write_soa_serial_to_buf(sldns_buffer* buf, struct query_info* qinfo,
+	uint32_t serial)
+{
+	sldns_buffer_set_position(buf, sldns_buffer_limit(buf));
+	sldns_buffer_set_limit(buf, sldns_buffer_capacity(buf));
+	/* Write compressed reference to the query */
+	sldns_buffer_write_u16(buf, PTR_CREATE(LDNS_HEADER_SIZE));
+	sldns_buffer_write_u16(buf, LDNS_RR_TYPE_SOA);
+	sldns_buffer_write_u16(buf, qinfo->qclass);
+	sldns_buffer_write_u32(buf, 3600); /* TTL */
+	sldns_buffer_write_u16(buf, 1+1+4*5); /* rdatalen */
+	sldns_buffer_write_u8(buf, 0); /* primary "." */
+	sldns_buffer_write_u8(buf, 0); /* email "." */
+	sldns_buffer_write_u32(buf, serial); /* serial */
+	sldns_buffer_write_u32(buf, 0); /* refresh */
+	sldns_buffer_write_u32(buf, 0); /* retry */
+	sldns_buffer_write_u32(buf, 0); /* expire */
+	sldns_buffer_write_u32(buf, 0); /* minimum */
+	sldns_buffer_flip(buf);
+}
+
 /** write a query over the TCP fd */
 static void
 write_q(int fd, int udp, SSL* ssl, sldns_buffer* buf, uint16_t id,
@@ -123,19 +148,36 @@ write_q(int fd, int udp, SSL* ssl, sldns_buffer* buf, uint16_t id,
 {
 	struct query_info qinfo;
 	size_t proxy_buf_limit = sldns_buffer_limit(proxy_buf);
+	int have_serial = 0, is_notify = 0;
+	uint32_t serial = 0;
 	/* qname */
 	qinfo.qname = sldns_str2wire_dname(strname, &qinfo.qname_len);
 	if(!qinfo.qname) {
 		printf("cannot parse query name: '%s'\n", strname);
 		exit(1);
 	}
 
-	/* qtype and qclass */
-	qinfo.qtype = sldns_get_rr_type_by_name(strtype);
-	if(qinfo.qtype == 0 && strcmp(strtype, "TYPE0") != 0) {
-		printf("cannot parse query type: '%s'\n", strtype);
-		exit(1);
+	/* qtype */
+	if(strncasecmp(strtype, "IXFR=", 5) == 0) {
+		serial = (uint32_t)atoi(strtype+5);
+		have_serial = 1;
+		qinfo.qtype = LDNS_RR_TYPE_IXFR;
+	} else if(strcasecmp(strtype, "NOTIFY") == 0) {
+		is_notify = 1;
+		qinfo.qtype = LDNS_RR_TYPE_SOA;
+	} else if(strncasecmp(strtype, "NOTIFY=", 7) == 0) {
+		serial = (uint32_t)atoi(strtype+7);
+		have_serial = 1;
+		is_notify = 1;
+		qinfo.qtype = LDNS_RR_TYPE_SOA;
+	} else {
+		qinfo.qtype = sldns_get_rr_type_by_name(strtype);
+		if(qinfo.qtype == 0 && strcmp(strtype, "TYPE0") != 0) {
+			printf("cannot parse query type: '%s'\n", strtype);
+			exit(1);
+		}
 	}
+	/* qclass */
 	qinfo.qclass = sldns_get_rr_class_by_name(strclass);
 	if(qinfo.qclass == 0 && strcmp(strclass, "CLASS0") != 0) {
 		printf("cannot parse query class: '%s'\n", strclass);
@@ -150,6 +192,21 @@ write_q(int fd, int udp, SSL* ssl, sldns_buffer* buf, uint16_t id,
 	sldns_buffer_write_u16_at(buf, 0, id);
 	sldns_buffer_write_u16_at(buf, 2, BIT_RD);
 
+	if(have_serial && qinfo.qtype == LDNS_RR_TYPE_IXFR) {
+		/* Attach serial to SOA record in the authority section. */
+		write_soa_serial_to_buf(buf, &qinfo, serial);
+		LDNS_NSCOUNT_SET(sldns_buffer_begin(buf), 1);
+	}
+	if(is_notify) {
+		LDNS_OPCODE_SET(sldns_buffer_begin(buf), LDNS_PACKET_NOTIFY);
+		LDNS_RD_CLR(sldns_buffer_begin(buf));
+		LDNS_AA_SET(sldns_buffer_begin(buf));
+		if(have_serial) {
+			write_soa_serial_to_buf(buf, &qinfo, serial);
+			LDNS_ANCOUNT_SET(sldns_buffer_begin(buf), 1);
+		}
+	}
+
 	if(1) {
 		/* add EDNS DO */
 		struct edns_data edns;
@@ -361,6 +418,7 @@ static int parse_pp2_client(const char* pp2_client, int udp,
 	sldns_buffer* proxy_buf)
 {
 	struct sockaddr_storage pp2_addr;
+	size_t bytes_written;
 	socklen_t pp2_addrlen = 0;
 	memset(&pp2_addr, 0, sizeof(pp2_addr));
 	if(*pp2_client == 0) return 0;
@@ -369,7 +427,9 @@ static int parse_pp2_client(const char* pp2_client, int udp,
 		exit(1);
 	}
 	sldns_buffer_clear(proxy_buf);
-	pp2_write_to_buf(proxy_buf, &pp2_addr, !udp);
+	bytes_written = pp2_write_to_buf(sldns_buffer_begin(proxy_buf),
+		sldns_buffer_remaining(proxy_buf), &pp2_addr, !udp);
+	sldns_buffer_set_position(proxy_buf, bytes_written);
 	sldns_buffer_flip(proxy_buf);
 	return 1;
 }
@@ -541,6 +601,8 @@ int main(int argc, char** argv)
 				break;
 			case 'p':
 				pp2_client = optarg;
+				pp_init(&sldns_write_uint16,
+					&sldns_write_uint32);
 				break;
 			case 'a':
 				onarrival = 1;
diff --git a/util/netevent.c b/util/netevent.c
@@ -892,24 +892,27 @@ static int udp_recv_needs_log(int err)
 static int consume_pp2_header(struct sldns_buffer* buf, struct comm_reply* rep,
 	int stream) {
 	size_t size;
-	struct pp2_header *header = pp2_read_header(buf);
-	if(header == NULL) return 0;
+	struct pp2_header *header;
+	int err = pp2_read_header(sldns_buffer_begin(buf),
+		sldns_buffer_remaining(buf));
+	if(err) return 0;
+	header = (struct pp2_header*)sldns_buffer_begin(buf);
 	size = PP2_HEADER_SIZE + ntohs(header->len);
 	if((header->ver_cmd & 0xF) == PP2_CMD_LOCAL) {
 		/* A connection from the proxy itself.
 		 * No need to do anything with addresses. */
 		goto done;
 	}
-	if(header->fam_prot == 0x00) {
+	if(header->fam_prot == PP2_UNSPEC_UNSPEC) {
 		/* Unspecified family and protocol. This could be used for
 		 * health checks by proxies.
 		 * No need to do anything with addresses. */
 		goto done;
 	}
 	/* Read the proxied address */
 	switch(header->fam_prot) {
-		case 0x11: /* AF_INET|STREAM */
-		case 0x12: /* AF_INET|DGRAM */
+		case PP2_INET_STREAM:
+		case PP2_INET_DGRAM:
 			{
 			struct sockaddr_in* addr =
 				(struct sockaddr_in*)&rep->client_addr;
@@ -920,8 +923,8 @@ static int consume_pp2_header(struct sldns_buffer* buf, struct comm_reply* rep,
 			}
 			/* Ignore the destination address; it should be us. */
 			break;
-		case 0x21: /* AF_INET6|STREAM */
-		case 0x22: /* AF_INET6|DGRAM */
+		case PP2_INET6_STREAM:
+		case PP2_INET6_DGRAM:
 			{
 			struct sockaddr_in6* addr =
 				(struct sockaddr_in6*)&rep->client_addr;
@@ -934,6 +937,10 @@ static int consume_pp2_header(struct sldns_buffer* buf, struct comm_reply* rep,
 			}
 			/* Ignore the destination address; it should be us. */
 			break;
+		default:
+			log_err("proxy_protocol: unsupported family and "
+				"protocol 0x%x", (int)header->fam_prot);
+			return 0;
 	}
 	rep->is_proxied = 1;
 done:
@@ -1813,19 +1820,25 @@ ssl_handle_read(struct comm_point* c)
 					return 0;
 				}
 				c->tcp_byte_count += r;
+				sldns_buffer_skip(c->buffer, r);
 				if(c->tcp_byte_count != current_read_size) return 1;
 				c->pp2_header_state = pp2_header_init;
 			}
 		}
 		if(c->pp2_header_state == pp2_header_init) {
-			header = pp2_read_header(c->buffer);
-			if(!header) {
+			int err;
+			err = pp2_read_header(
+				sldns_buffer_begin(c->buffer),
+				sldns_buffer_limit(c->buffer));
+			if(err) {
 				log_err("proxy_protocol: could not parse "
-					"PROXYv2 header");
+					"PROXYv2 header (%s)",
+					pp_lookup_error(err));
 				return 0;
 			}
+			header = (struct pp2_header*)sldns_buffer_begin(c->buffer);
 			want_read_size = ntohs(header->len);
-			if(sldns_buffer_remaining(c->buffer) <
+			if(sldns_buffer_limit(c->buffer) <
 				PP2_HEADER_SIZE + want_read_size) {
 				log_err_addr("proxy_protocol: not enough "
 					"buffer size to read PROXYv2 header", "",
@@ -1874,6 +1887,7 @@ ssl_handle_read(struct comm_point* c)
 					return 0;
 				}
 				c->tcp_byte_count += r;
+				sldns_buffer_skip(c->buffer, r);
 				if(c->tcp_byte_count != current_read_size) return 1;
 				c->pp2_header_state = pp2_header_done;
 			}
@@ -1884,6 +1898,7 @@ ssl_handle_read(struct comm_point* c)
 				c->repinfo.remote_addrlen);
 			return 0;
 		}
+		sldns_buffer_flip(c->buffer);
 		if(!consume_pp2_header(c->buffer, &c->repinfo, 1)) {
 			log_err_addr("proxy_protocol: could not consume "
 				"PROXYv2 header", "", &c->repinfo.remote_addr,
@@ -2205,19 +2220,25 @@ comm_point_tcp_handle_read(int fd, struct comm_point* c, int short_ok)
 					goto recv_error_initial;
 				}
 				c->tcp_byte_count += r;
+				sldns_buffer_skip(c->buffer, r);
 				if(c->tcp_byte_count != current_read_size) return 1;
 				c->pp2_header_state = pp2_header_init;
 			}
 		}
 		if(c->pp2_header_state == pp2_header_init) {
-			header = pp2_read_header(c->buffer);
-			if(!header) {
+			int err;
+			err = pp2_read_header(
+				sldns_buffer_begin(c->buffer),
+				sldns_buffer_limit(c->buffer));
+			if(err) {
 				log_err("proxy_protocol: could not parse "
-					"PROXYv2 header");
+					"PROXYv2 header (%s)",
+					pp_lookup_error(err));
 				return 0;
 			}
+			header = (struct pp2_header*)sldns_buffer_begin(c->buffer);
 			want_read_size = ntohs(header->len);
-			if(sldns_buffer_remaining(c->buffer) <
+			if(sldns_buffer_limit(c->buffer) <
 				PP2_HEADER_SIZE + want_read_size) {
 				log_err_addr("proxy_protocol: not enough "
 					"buffer size to read PROXYv2 header", "",
@@ -2244,6 +2265,7 @@ comm_point_tcp_handle_read(int fd, struct comm_point* c, int short_ok)
 					goto recv_error;
 				}
 				c->tcp_byte_count += r;
+				sldns_buffer_skip(c->buffer, r);
 				if(c->tcp_byte_count != current_read_size) return 1;
 				c->pp2_header_state = pp2_header_done;
 			}
@@ -2254,6 +2276,7 @@ comm_point_tcp_handle_read(int fd, struct comm_point* c, int short_ok)
 				c->repinfo.remote_addrlen);
 			return 0;
 		}
+		sldns_buffer_flip(c->buffer);
 		if(!consume_pp2_header(c->buffer, &c->repinfo, 1)) {
 			log_err_addr("proxy_protocol: could not consume "
 				"PROXYv2 header", "", &c->repinfo.remote_addr,
diff --git a/util/proxy_protocol.c b/util/proxy_protocol.c
diff --git a/util/proxy_protocol.h b/util/proxy_protocol.h

Original file line number	Diff line number	Diff line change
`@@ -66,6 +66,7 @@`
`66`	`66`	`#include "util/data/msgencode.h"`
`67`	`67`	`#include "util/data/dname.h"`
`68`	`68`	`#include "util/fptr_wlist.h"`
	`69`	`+#include "util/proxy_protocol.h"`
`69`	`70`	`#include "util/tube.h"`
`70`	`71`	`#include "util/edns.h"`
`71`	`72`	`#include "util/timeval_func.h"`
`@@ -2317,6 +2318,7 @@ worker_init(struct worker* worker, struct config_file *cfg,`
`2317`	`2318`	`worker->env.cfg->stat_interval);`
`2318`	`2319`	`worker_restart_timer(worker);`
`2319`	`2320`	`}`
	`2321`	`+ pp_init(&sldns_write_uint16, &sldns_write_uint32);`
`2320`	`2322`	`return 1;`
`2321`	`2323`	`}`
`2322`	`2324`