Return error if hostname too long for remote resolve

Resolves: RHEL-11467

0033-curl-7.76.1-CVE-2023-38545.patch

+From 1d66562c67fc0099d0fd882c693e51dd0b10c45c Mon Sep 17 00:00:00 2001
+From: Jay Satiro <raysatiro@yahoo.com>
+Date: Sat, 30 Sep 2023 03:40:02 -0400
+Subject: [PATCH] socks: return error if hostname too long for remote resolve
+
+Prior to this change the state machine attempted to change the remote
+resolve to a local resolve if the hostname was longer than 255
+characters. Unfortunately that did not work as intended and caused a
+security issue.
+
+Name resolvers cannot resolve hostnames longer than 255 characters.
+
+Bug: https://curl.se/docs/CVE-2023-38545.html
+---
+ lib/socks.c             |  8 +++---
+ tests/data/Makefile.inc |  2 +-
+ tests/data/test728      | 64 +++++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 69 insertions(+), 5 deletions(-)
+ create mode 100644 tests/data/test728
+
+diff --git a/lib/socks.c b/lib/socks.c
+index c492d663c..a7b5ab07e 100644
+--- a/lib/socks.c
++++ b/lib/socks.c
+@@ -531,13 +531,13 @@ CURLproxycode Curl_SOCKS5(const char *proxy_user,
+       infof(data, "SOCKS5: connecting to HTTP proxy %s port %d\n",
+             hostname, remote_port);
+ 
+     /* RFC1928 chapter 5 specifies max 255 chars for domain name in packet */
+     if(!socks5_resolve_local && hostname_len > 255) {
+-      infof(data, "SOCKS5: server resolving disabled for hostnames of "
+-            "length > 255 [actual len=%zu]\n", hostname_len);
+-      socks5_resolve_local = TRUE;
++      failf(data, "SOCKS5: the destination hostname is too long to be "
++            "resolved remotely by the proxy.");
++      return CURLPX_LONG_HOSTNAME;
+     }
+ 
+     if(auth & ~(CURLAUTH_BASIC | CURLAUTH_GSSAPI))
+       infof(data,
+             "warning: unsupported value passed to CURLOPT_SOCKS5_AUTH: %lu\n",
+@@ -855,7 +855,7 @@ CONNECT_RESOLVE_REMOTE:
+ 
+     if(!socks5_resolve_local) {
+       socksreq[len++] = 3; /* ATYP: domain name = 3 */
+-      socksreq[len++] = (char) hostname_len; /* one byte address length */
++      socksreq[len++] = (unsigned char) hostname_len; /* one byte length */
+       memcpy(&socksreq[len], hostname, hostname_len); /* address w/o NULL */
+       len += hostname_len;
+       infof(data, "SOCKS5 connect to %s:%d (remotely resolved)\n",
+diff --git a/tests/data/Makefile.inc b/tests/data/Makefile.inc
+index 081e344d4..62ee53578 100644
+--- a/tests/data/Makefile.inc
++++ b/tests/data/Makefile.inc
+@@ -99,7 +99,7 @@ test672 test673 test674 test675 test676 test677 test678 test679 test680 \
+ \
+ test700 test701 test702 test703 test704 test705 test706 test707 test708 \
+ test709 test710 test711 test712 test713 test714 test715 test716 test717 \
+-test718 \
++test718 test728 \
+ \
+ test800 test801 test802 test803 test804 test805 test806 test807 test808 \
+ test809 test810 test811 test812 test813 test814 test815 test816 test817 \
+diff --git a/tests/data/test728 b/tests/data/test728
+new file mode 100644
+index 000000000..05bcf2883
+--- /dev/null
++++ b/tests/data/test728
+@@ -0,0 +1,64 @@
++<testcase>
++<info>
++<keywords>
++HTTP
++HTTP GET
++SOCKS5
++SOCKS5h
++followlocation
++</keywords>
++</info>
++
++#
++# Server-side
++<reply>
++# The hostname in this redirect is 256 characters and too long (> 255) for
++# SOCKS5 remote resolve. curl must return error CURLE_PROXY in this case.
++<data>
++HTTP/1.1 301 Moved Permanently
++Location: http://AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA/
++Content-Length: 0
++Connection: close
++
++</data>
++</reply>
++
++#
++# Client-side
++<client>
++<features>
++proxy
++</features>
++<server>
++http
++socks5
++</server>
++ <name>
++SOCKS5h with HTTP redirect to hostname too long
++ </name>
++ <command>
++--no-progress-meter --location --proxy socks5h://%HOSTIP:%SOCKSPORT http://%HOSTIP:%HTTPPORT/%TESTNUMBER
++</command>
++</client>
++
++#
++# Verify data after the test has been "shot"
++<verify>
++<protocol crlf="yes">
++GET /%TESTNUMBER HTTP/1.1
++Host: %HOSTIP:%HTTPPORT
++User-Agent: curl/%VERSION
++Accept: */*
++
++</protocol>
++<errorcode>
++97
++</errorcode>
++# the error message is verified because error code CURLE_PROXY (97) may be
++# returned for any number of reasons and we need to make sure it is
++# specifically for the reason below so that we know the check is working.
++<stderr mode="text">
++curl: (97) SOCKS5: the destination hostname is too long to be resolved remotely by the proxy.
++</stderr>
++</verify>
++</testcase>
+-- 
+2.42.0
+

curl.spec

 Summary: A utility for getting files from remote servers (FTP, HTTP, and others)
 Name: curl
 Version: 7.76.1
-Release: 27%{?dist}
+Release: 28%{?dist}
 License: MIT
 Source: https://curl.se/download/%{name}-%{version}.tar.xz
 
@@ -98,6 +98,9 @@ Patch31:  0031-curl-7.76.1-CVE-2023-28321.patch
 # when keyboard-interactive auth fails, try password
 Patch32:  0032-curl-7.76.1-password-when-keyboard-interactive-fails.patch
 
+# return error if hostname too long for remote resolve
+Patch33:  0033-curl-7.76.1-CVE-2023-38545.patch
+
 # patch making libcurl multilib ready
 Patch101: 0101-curl-7.32.0-multilib.patch
 
@@ -304,6 +307,7 @@ be installed.
 %patch30 -p1
 %patch31 -p1
 %patch32 -p1
+%patch33 -p1
 
 # Fedora patches
 %patch101 -p1
@@ -529,6 +533,9 @@ rm -f ${RPM_BUILD_ROOT}%{_libdir}/libcurl.la
 %{_libdir}/libcurl.so.4.[0-9].[0-9].minimal
 
 %changelog
+* Tue Oct 10 2023 Jacek Migacz <jmigacz@redhat.com> - 7.76.1-28
+- return error if hostname too long for remote resolve (CVE-2023-38545)
+
 * Tue Sep 12 2023 Jacek Migacz <jmigacz@redhat.com> - 7.76.1-27
 - when keyboard-interactive auth fails, try password (#2229800)