>From acd969c34df57ae4bfad96a1b395a77aef212c3e Mon Sep 17 00:00:00 2001 From: Simo Sorce Date: Wed, 4 Sep 2013 15:02:43 -0400 Subject: [PATCH] krb5: Ingnore unknown expansion sequences Recently support was added to use also libkrb5 style expansions that uses a %{varname} type of template. There are a number of templates we do not care/can't expand in sssd. The current code misses tests and failed to properly preserve some of the templates we do not want to handle. Addiotionally in order to be future proof this patch treats unknown templates as pass-through templates and defer any error checking to libkrb5, so that sssd is consistent with how kinit would behave. Resolves: https://fedorahosted.org/sssd/ticket/2076 --- src/providers/krb5/krb5_utils.c | 45 ++++++++++++++--------------------------- src/tests/krb5_utils-tests.c | 31 ++++++++++++++++++++++++++++ 2 files changed, 46 insertions(+), 30 deletions(-) diff --git a/src/providers/krb5/krb5_utils.c b/src/providers/krb5/krb5_utils.c index df7892153d2c16fd3e485ed5013454233d228936..6bf1cf610dd20afc7a600e9505c4bae2ff675fcc 100644 --- a/src/providers/krb5/krb5_utils.c +++ b/src/providers/krb5/krb5_utils.c @@ -157,24 +157,14 @@ done: return ret; } -#define S_EXP_TEMP "{TEMP}" -#define L_EXP_TEMP (sizeof(S_EXP_TEMP) - 1) #define S_EXP_UID "{uid}" #define L_EXP_UID (sizeof(S_EXP_UID) - 1) #define S_EXP_USERID "{USERID}" #define L_EXP_USERID (sizeof(S_EXP_USERID) - 1) #define S_EXP_EUID "{euid}" #define L_EXP_EUID (sizeof(S_EXP_EUID) - 1) -#define S_EXP_NULL "{null}" -#define L_EXP_NULL (sizeof(S_EXP_NULL) - 1) #define S_EXP_USERNAME "{username}" #define L_EXP_USERNAME (sizeof(S_EXP_USERNAME) - 1) -#define S_EXP_LIBDIR "{LIBDIR}" -#define L_EXP_LIBDIR (sizeof(S_EXP_LIBDIR) - 1) -#define S_EXP_BINDIR "{BINDIR}" -#define L_EXP_BINDIR (sizeof(S_EXP_BINDIR) - 1) -#define S_EXP_SBINDIR "{SBINDIR}" -#define L_EXP_SBINDIR (sizeof(S_EXP_SBINDIR) - 1) char *expand_ccname_template(TALLOC_CTX *mem_ctx, struct krb5child_req *kr, const char *template, bool file_mode, @@ -325,11 +315,7 @@ char *expand_ccname_template(TALLOC_CTX *mem_ctx, struct krb5child_req *kr, /* Additional syntax from krb5.conf default_ccache_name */ case '{': - if (strncmp(n, S_EXP_TEMP, L_EXP_TEMP) == 0) { - /* let the libkrb5 library resolve this */ - result = talloc_asprintf_append(result, "%%"S_EXP_TEMP); - n += L_EXP_TEMP - 1; - } else if (strncmp(n , S_EXP_UID, L_EXP_UID) == 0) { + if (strncmp(n , S_EXP_UID, L_EXP_UID) == 0) { action = 'U'; n += L_EXP_UID - 1; rerun = true; @@ -346,26 +332,25 @@ char *expand_ccname_template(TALLOC_CTX *mem_ctx, struct krb5child_req *kr, n += L_EXP_EUID - 1; rerun = true; continue; - } else if (strncmp(n , S_EXP_NULL, L_EXP_NULL) == 0) { - /* skip immediately */ - n += L_EXP_NULL - 1; } else if (strncmp(n , S_EXP_USERNAME, L_EXP_USERNAME) == 0) { action = 'u'; n += L_EXP_USERNAME - 1; rerun = true; continue; - } else if (strncmp(n , S_EXP_LIBDIR, L_EXP_LIBDIR) == 0) { - /* skip, only the libkrb5 library can resolve this */ - result = talloc_asprintf_append(result, "%%"S_EXP_LIBDIR); - n += L_EXP_LIBDIR - 1; - } else if (strncmp(n , S_EXP_BINDIR, L_EXP_BINDIR) == 0) { - /* skip, only the libkrb5 library can resolve this */ - result = talloc_asprintf_append(result, "%%"S_EXP_BINDIR); - n += L_EXP_BINDIR - 1; - } else if (strncmp(n , S_EXP_SBINDIR, L_EXP_SBINDIR) == 0) { - /* skip, only the libkrb5 library can resolve this */ - result = talloc_asprintf_append(result, "%%"S_EXP_SBINDIR); - n += L_EXP_SBINDIR - 1; + } else { + /* ignore any expansion variable we do not understand and + * let libkrb5 hndle it or fail */ + name = n; + n = strchr(name, '}'); + if (!n) { + DEBUG(SSSDBG_CRIT_FAILURE, ( + "Invalid substitution sequence in cache " + "template. Missing closing '}' in [%s].\n", + template)); + goto done; + } + result = talloc_asprintf_append(result, "%s%%%.*s", p, + (int)(n - name + 1), name); } break; default: diff --git a/src/tests/krb5_utils-tests.c b/src/tests/krb5_utils-tests.c index 4be3ad04eff73b9f27a05efcfa6a93f57ec8105f..f22f385d444f9f61735af288e5a7774d0ecc989a 100644 --- a/src/tests/krb5_utils-tests.c +++ b/src/tests/krb5_utils-tests.c @@ -673,6 +673,36 @@ START_TEST(test_no_substitution) } END_TEST +START_TEST(test_krb5_style_expansion) +{ + char *result; + int ret; + bool private_path = false; + const char *file_template; + const char *expected; + + file_template = BASE"/%{uid}/%{USERID}/%{euid}/%{username}"; + expected = BASE"/"UID"/"UID"/"UID"/"USERNAME; + result = expand_ccname_template(tmp_ctx, kr, file_template, true, + true, &private_path); + + fail_unless(result != NULL, "Cannot expand template [%s].", file_template); + fail_unless(strcmp(result, expected) == 0, + "Expansion failed, result [%s], expected [%s].", + result, expected); + + file_template = BASE"/%{unknown}"; + expected = BASE"/%{unknown}"; + result = expand_ccname_template(tmp_ctx, kr, file_template, true, + false, &private_path); + + fail_unless(result != NULL, "Cannot expand template [%s].", file_template); + fail_unless(strcmp(result, expected) == 0, + "Expansion failed, result [%s], expected [%s].", + result, expected); +} +END_TEST + START_TEST(test_compare_principal_realm) { int ret; @@ -738,6 +768,7 @@ Suite *krb5_utils_suite (void) tcase_add_test (tc_ccname_template, test_pid); tcase_add_test (tc_ccname_template, test_percent); tcase_add_test (tc_ccname_template, test_multiple_substitutions); + tcase_add_test (tc_ccname_template, test_krb5_style_expansion); suite_add_tcase (s, tc_ccname_template); TCase *tc_create_dir = tcase_create("create_dir"); -- 1.8.3.1