According to INSTALL file, OpenSSL 1.0.2 is still supported by HAProxy, however OpenSSL 1.0.2 lacking CRYPTO_memcmp(), haproxy does not build:
$ make V=1 TARGET=linux-glibc USE_NS= USE_OPENSSL=1 .. cc -Iinclude -O2 -g -Wall -Wextra -Wdeclaration-after-statement -fwrapv -Wno-unused-label -Wno-sign-compare -Wno-unused-parameter -Wno-clobbered -Wno-missing-field-initializers -Wtype-limits -DUSE_EPOLL -DUSE_NETFILTER -DUSE_POLL -DUSE_THREAD -DUSE_BACKTRACE -DUSE_TPROXY -DUSE_LINUX_TPROXY -DUSE_LINUX_SPLICE -DUSE_LIBCRYPT -DUSE_CRYPT_H -DUSE_GETADDRINFO -DUSE_OPENSSL -DUSE_FUTEX -DUSE_ACCEPT4 -DUSE_CPU_AFFINITY -DUSE_TFO -DUSE_DL -DUSE_RT -DUSE_PRCTL -DUSE_THREAD_DUMP -DCONFIG_HAPROXY_VERSION=\"2.4-dev5-37286a-78\" -DCONFIG_HAPROXY_DATE=\"2021/01/21\" -c -o src/sample.o src/sample.c src/sample.c: In function 'sample_conv_secure_memcmp': src/sample.c:3130:2: warning: implicit declaration of function 'CRYPTO_memcmp' .. cc -g -o haproxy src/ev_poll.o src/ev_epoll.o src/ssl_sample.o src/ssl_sock.o src/ssl_crtlist.o src/ssl_ckch.o src/ssl_utils.o src/cfgparse-ssl.o src/mux_h2.o src/mux_fcgi.o src/http_ana.o src/stream.o src/mux_h1.o src/stats.o src/flt_spoe.o src/backend.o src/tcpcheck.o src/server.o src/tools.o src/cli.o src/cfgparse.o src/log.o src/cfgparse-listen.o src/check.o src/stick_table.o src/peers.o src/dns.o src/stream_interface.o src/sample.o src/http_htx.o src/haproxy.o src/http_act.o src/proxy.o src/pattern.o src/listener.o src/cache.o src/http_fetch.o src/session.o src/connection.o src/sink.o src/task.o src/filters.o src/fcgi-app.o src/tcp_rules.o src/payload.o src/mux_pt.o src/flt_http_comp.o src/cfgparse-global.o src/vars.o src/map.o src/debug.o src/queue.o src/h1_htx.o src/compression.o src/mworker.o src/flt_trace.o src/acl.o src/trace.o src/proto_sockpair.o src/proto_tcp.o src/lb_chash.o src/htx.o src/xprt_handshake.o src/h1.o src/sock.o src/ring.o src/extcheck.o src/tcp_sample.o src/frontend.o src/h2.o src/channel.o src/applet.o src/tcp_act.o src/http_rules.o src/fd.o src/raw_sock.o src/pool.o src/mailers.o src/http_conv.o src/lb_fwrr.o src/proto_uxst.o src/http.o src/lb_fwlc.o src/lb_fas.o src/activity.o src/sock_unix.o src/protocol.o src/mworker-prog.o src/signal.o src/proto_udp.o src/lb_map.o src/sock_inet.o src/ev_select.o src/cfgparse-tcp.o src/action.o src/thread.o src/sha1.o src/ebmbtree.o src/cfgparse-unix.o src/dict.o src/time.o src/hpack-dec.o src/arg.o src/hpack-tbl.o src/eb64tree.o src/chunk.o src/shctx.o src/regex.o src/fcgi.o src/eb32tree.o src/eb32sctree.o src/dynbuf.o src/pipe.o src/lru.o src/ebimtree.o src/uri_auth.o src/freq_ctr.o src/ebsttree.o src/ebistree.o src/auth.o src/wdt.o src/http_acl.o src/hpack-enc.o src/hpack-huff.o src/ebtree.o src/base64.o src/hash.o src/dgram.o src/version.o src/fix.o src/mqtt.o -lcrypt -ldl -lrt -lpthread -Wl,--export-dynamic -lssl -lcrypto -ldl src/sample.o: In function `sample_conv_secure_memcmp': src/sample.c:3130: undefined reference to `CRYPTO_memcmp' collect2: ld returned 1 exit status make: *** [haproxy] Error 1 See: https://git.openssl.org/?p=openssl.git;a=commitdiff;h=f5cd3561ba9363e6bcc58fcb6b1e94930f81967d $ git describe --contains f5cd3561ba9363e6bcc58fcb6b1e94930f81967d OpenSSL_1_0_2-beta1~439 Since secure_memcmp is meant to be used in constant time sensible environment, this commit removes the converter when the version of OpenSSL does not meant the requirement. Adjusting related documentation, pointing the user to strcmp instead. Cc: Emeric Brun <eb...@haproxy.com> Cc: William Lallemand <wlallem...@haproxy.com> --- doc/configuration.txt | 6 +++++- src/sample.c | 12 +++++++----- 2 files changed, 12 insertions(+), 6 deletions(-) diff --git a/doc/configuration.txt b/doc/configuration.txt index 899bdf553a85..f25da9c1bfa6 100644 --- a/doc/configuration.txt +++ b/doc/configuration.txt @@ -15996,7 +15996,11 @@ secure_memcmp(<var>) performed in constant time. Please note that this converter is only available when haproxy has been - compiled with USE_OPENSSL. + compiled with USE_OPENSSL. Requires at least OpenSSL 1.0.2. + + See also the strcmp converter if you need to compare two binary + strings without concern related to constant time or if OpenSSL is not + enabled. Example : diff --git a/src/sample.c b/src/sample.c index bf2de2a2522d..bb12789b551f 100644 --- a/src/sample.c +++ b/src/sample.c @@ -3100,12 +3100,14 @@ static int sample_conv_strcmp(const struct arg *arg_p, struct sample *smp, void return 1; } -#ifdef USE_OPENSSL +#if defined(USE_OPENSSL) && HA_OPENSSL_VERSION_NUMBER > 0x1000200fL /* Compares bytestring with a variable containing a bytestring. Return value * is `true` if both bytestrings are bytewise identical and `false` otherwise. * - * Comparison will be performed in constant time if both bytestrings are of - * the same length. If the lengths differ execution time will not be constant. + * Comparison will be performed in constant time if the library support + * constant time memcmp (starting with OpenSSL 1.0.2) and if both + * bytestrings are of the same length. Otherwise execution time will not + * be constant. */ static int sample_conv_secure_memcmp(const struct arg *arg_p, struct sample *smp, void *private) { @@ -3422,7 +3424,7 @@ static int smp_check_strcmp(struct arg *args, struct sample_conv *conv, return 0; } -#ifdef USE_OPENSSL +#if defined(USE_OPENSSL) && HA_OPENSSL_VERSION_NUMBER > 0x1000200fL /* This function checks the "secure_memcmp" converter's arguments and extracts the * variable name and its scope. */ @@ -3988,7 +3990,7 @@ static struct sample_conv_kw_list sample_conv_kws = {ILH, { #endif { "concat", sample_conv_concat, ARG3(1,STR,STR,STR), smp_check_concat, SMP_T_STR, SMP_T_STR }, { "strcmp", sample_conv_strcmp, ARG1(1,STR), smp_check_strcmp, SMP_T_STR, SMP_T_SINT }, -#ifdef USE_OPENSSL +#if defined(USE_OPENSSL) && HA_OPENSSL_VERSION_NUMBER > 0x1000200fL { "secure_memcmp", sample_conv_secure_memcmp, ARG1(1,STR), smp_check_secure_memcmp, SMP_T_BIN, SMP_T_BOOL }, #endif
