git: 7200fdb9da3a - stable/13 - sbin/ipfw: Fix parsing error in table based forward

[Lutz Donnerhacke]

The branch stable/13 has been updated by donner:

URL: https://cgit.FreeBSD.org/src/commit/?id=7200fdb9da3ac04ef8e577c947969a0ba8d69128

commit 7200fdb9da3ac04ef8e577c947969a0ba8d69128
Author:     Lutz Donnerhacke <donner at FreeBSD.org>
AuthorDate: 2021-05-07 18:59:34 +0000
Commit:     Lutz Donnerhacke <donner at FreeBSD.org>
CommitDate: 2021-05-18 06:10:00 +0000

    sbin/ipfw: Fix parsing error in table based forward
    
    The argument parser does not recognise the optional port for an
    "tablearg" argument.  Fix simplifies the code by make the internal
    representation expicit for the parser.  Includes the fix from D30208.
    
    PR:             252744
    Reported by:    <bugs.freebsd.org at mx.zzux.com>
    Approved by:    nc
    Tested by:      <bugs.freebsd.org at mx.zzux.com>
    Differential Revision: https://reviews.freebsd.org/D30164
    
    (cherry picked from commit 6cb13813caa09305046e0cecad8bba3ae2287b0d)
    (cherry picked from commit f6f297871d469daf808f78faead8f950a2c81e36)
---
 sbin/ipfw/ipfw2.c | 88 +++++++++++++++++++++++++++----------------------------
 1 file changed, 43 insertions(+), 45 deletions(-)

diff --git a/sbin/ipfw/ipfw2.c b/sbin/ipfw/ipfw2.c
index c17fbbca7dfa..fb1d9a4a180b 100644
--- a/sbin/ipfw/ipfw2.c
+++ b/sbin/ipfw/ipfw2.c
@@ -4021,57 +4021,55 @@ chkarg:
 
 		NEED1("missing forward address[:port]");
 
-		if (_substrcmp(*av, "tablearg") == 0) {
-			family = PF_INET;
-			((struct sockaddr_in*)&result)->sin_addr.s_addr =
-			    INADDR_ANY;
-		} else {
-			/*
-			 * Are we an bracket-enclosed IPv6 address?
-			 */
-			if (strchr(*av, '['))
-				(*av)++;
+		if (strncmp(*av, "tablearg", 8) == 0 &&
+		    ((*av)[8] == '\0' || (*av)[8] == ',' || (*av)[8] == ':'))
+			memcpy(++(*av), "0.0.0.0", 7);
 
-			/*
-			 * locate the address-port separator (':' or ',')
-			 */
-			s = strchr(*av, ',');
-			if (s == NULL) {
-				s = strchr(*av, ']');
-				/* Prevent erroneous parsing on brackets. */
-				if (s != NULL)
-					*(s++) = '\0';
-				else
-					s = *av;
-
-				/* Distinguish between IPv4:port and IPv6 cases. */
-				s = strchr(s, ':');
-				if (s && strchr(s+1, ':'))
-					s = NULL; /* no port */
-			}
+		/*
+		 * Are we an bracket-enclosed IPv6 address?
+		 */
+		if (strchr(*av, '['))
+			(*av)++;
 
-			if (s != NULL) {
-				/* Terminate host portion and set s to start of port. */
+		/*
+		 * locate the address-port separator (':' or ',')
+		 */
+		s = strchr(*av, ',');
+		if (s == NULL) {
+			s = strchr(*av, ']');
+			/* Prevent erroneous parsing on brackets. */
+			if (s != NULL)
 				*(s++) = '\0';
-				i = strtoport(s, &end, 0 /* base */, 0 /* proto */);
-				if (s == end)
-					errx(EX_DATAERR,
-					    "illegal forwarding port ``%s''", s);
-				port_number = (u_short)i;
-			}
+			else
+				s = *av;
 
-			/*
-			 * Resolve the host name or address to a family and a
-			 * network representation of the address.
-			 */
-			if (getaddrinfo(*av, NULL, NULL, &res))
-				errx(EX_DATAERR, NULL);
-			/* Just use the first host in the answer. */
-			family = res->ai_family;
-			memcpy(&result, res->ai_addr, res->ai_addrlen);
-			freeaddrinfo(res);
+			/* Distinguish between IPv4:port and IPv6 cases. */
+			s = strchr(s, ':');
+			if (s && strchr(s+1, ':'))
+				s = NULL; /* no port */
 		}
 
+		if (s != NULL) {
+			/* Terminate host portion and set s to start of port. */
+			*(s++) = '\0';
+			i = strtoport(s, &end, 0 /* base */, 0 /* proto */);
+			if (s == end)
+				errx(EX_DATAERR,
+				    "illegal forwarding port ``%s''", s);
+			port_number = (u_short)i;
+		}
+
+		/*
+		 * Resolve the host name or address to a family and a
+		 * network representation of the address.
+		 */
+		if (getaddrinfo(*av, NULL, NULL, &res))
+			errx(EX_DATAERR, NULL);
+		/* Just use the first host in the answer. */
+		family = res->ai_family;
+		memcpy(&result, res->ai_addr, res->ai_addrlen);
+		freeaddrinfo(res);
+
  		if (family == PF_INET) {
 			ipfw_insn_sa *p = (ipfw_insn_sa *)action;