aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJon Simons <jon@jonsimons.org>2017-07-11 19:34:18 -0400
committerAndreas Schneider <asn@cryptomilk.org>2017-07-18 09:32:31 +0200
commit380390c4b6dca9bda52707807b3ee577f758b107 (patch)
tree265f0eee4c3e12a5936a93c5221bdffb742b2711
parente66f370682927ca8bd7ae0e7544754c6f4ac4969 (diff)
downloadlibssh-380390c4b6dca9bda52707807b3ee577f758b107.tar.gz
libssh-380390c4b6dca9bda52707807b3ee577f758b107.tar.xz
libssh-380390c4b6dca9bda52707807b3ee577f758b107.zip
misc: relax fatal errors in ssh_analyze_banner
Relax the cases where `ssh_analyze_banner` fails to extract a major and minor version from banners which appear like OpenSSH banners. Update the tests to demonstrate that now a banner as might be sent by `ssh-keyscan(1)` ("SSH-2.0-OpenSSH-keyscan") no longer returns failure. Signed-off-by: Jon Simons <jon@jonsimons.org> Reviewed-by: Andreas Schneider <asn@cryptomilk.org>
-rw-r--r--src/misc.c17
-rw-r--r--tests/unittests/torture_misc.c40
2 files changed, 26 insertions, 31 deletions
diff --git a/src/misc.c b/src/misc.c
index 21276c68..5b260b15 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -844,6 +844,7 @@ int ssh_analyze_banner(ssh_session session, int server, int *ssh1, int *ssh2) {
return -1;
}
+ /* Make a best-effort to extract OpenSSH version numbers. */
openssh = strstr(banner, "OpenSSH");
if (openssh != NULL) {
char *tmp = NULL;
@@ -861,11 +862,8 @@ int ssh_analyze_banner(ssh_session session, int server, int *ssh1, int *ssh2) {
((errno == ERANGE) && (major == ULONG_MAX)) ||
((errno != 0) && (major == 0)) ||
((major < 1) || (major > 100))) {
- ssh_set_error(session,
- SSH_FATAL,
- "Invalid major version number: %s",
- banner);
- return -1;
+ /* invalid major */
+ goto done;
}
minor = strtoul(openssh + 10, &tmp, 10);
@@ -873,12 +871,10 @@ int ssh_analyze_banner(ssh_session session, int server, int *ssh1, int *ssh2) {
((errno == ERANGE) && (major == ULONG_MAX)) ||
((errno != 0) && (major == 0)) ||
(minor > 100)) {
- ssh_set_error(session,
- SSH_FATAL,
- "Invalid minor version number: %s",
- banner);
- return -1;
+ /* invalid minor */
+ goto done;
}
+
session->openssh = SSH_VERSION_INT(((int) major), ((int) minor), 0);
SSH_LOG(SSH_LOG_RARE,
@@ -887,6 +883,7 @@ int ssh_analyze_banner(ssh_session session, int server, int *ssh1, int *ssh2) {
}
}
+done:
return 0;
}
diff --git a/tests/unittests/torture_misc.c b/tests/unittests/torture_misc.c
index f11f4488..1d0e0f5c 100644
--- a/tests/unittests/torture_misc.c
+++ b/tests/unittests/torture_misc.c
@@ -315,35 +315,33 @@ static void torture_ssh_analyze_banner(void **state) {
assert_server_banner_accepted("SSH-2.0-OpenSSH_1.99", 0, 1);
assert_int_equal(SSH_VERSION_INT(1, 99, 0), session->openssh);
- /* OpenSSH banners: major, minor version limits */
- reset_banner_test();
- assert_client_banner_rejected("SSH-2.0-OpenSSH_0.99p1");
- reset_banner_test();
- assert_server_banner_rejected("SSH-2.0-OpenSSH_0.99p1");
- reset_banner_test();
- assert_client_banner_rejected("SSH-2.0-OpenSSH_1.101p1");
- reset_banner_test();
- assert_server_banner_rejected("SSH-2.0-OpenSSH_1.101p1");
+ /* OpenSSH banners: major, minor version limits result in zero */
+ assert_client_banner_accepted("SSH-2.0-OpenSSH_0.99p1", 0, 1);
+ assert_int_equal(0, session->openssh);
+ assert_server_banner_accepted("SSH-2.0-OpenSSH_0.99p1", 0, 1);
+ assert_int_equal(0, session->openssh);
+ assert_client_banner_accepted("SSH-2.0-OpenSSH_1.101p1", 0, 1);
+ assert_int_equal(0, session->openssh);
+ assert_server_banner_accepted("SSH-2.0-OpenSSH_1.101p1", 0, 1);
+ assert_int_equal(0, session->openssh);
- /* OpenSSH banners: bogus major */
- reset_banner_test();
- assert_client_banner_rejected("SSH-2.0-OpenSSH_X.9p1");
- reset_banner_test();
- assert_server_banner_rejected("SSH-2.0-OpenSSH_X.9p1");
+ /* OpenSSH banners: bogus major results in zero */
+ assert_client_banner_accepted("SSH-2.0-OpenSSH_X.9p1", 0, 1);
+ assert_int_equal(0, session->openssh);
+ assert_server_banner_accepted("SSH-2.0-OpenSSH_X.9p1", 0, 1);
+ assert_int_equal(0, session->openssh);
- /* OpenSSH banners: bogus minor */
- reset_banner_test();
- assert_server_banner_rejected("SSH-2.0-OpenSSH_5.Yp1");
- reset_banner_test();
- assert_client_banner_rejected("SSH-2.0-OpenSSH_5.Yp1");
+ /* OpenSSH banners: bogus minor results in zero */
+ assert_server_banner_accepted("SSH-2.0-OpenSSH_5.Yp1", 0, 1);
+ assert_int_equal(0, session->openssh);
+ assert_client_banner_accepted("SSH-2.0-OpenSSH_5.Yp1", 0, 1);
+ assert_int_equal(0, session->openssh);
/* OpenSSH banners: ssh-keyscan(1) */
- #if 0 /* these don't pass */
assert_client_banner_accepted("SSH-2.0-OpenSSH-keyscan", 0, 1);
assert_int_equal(0, session->openssh);
assert_server_banner_accepted("SSH-2.0-OpenSSH-keyscan", 0, 1);
assert_int_equal(0, session->openssh);
- #endif /* these don't pass */
ssh_free(session);
}