Have OSSL_PARAM_allocate_from_text() fail on odd number of hex digits

The failure would be caught later on, so this went unnoticed, until someone tried with just one hex digit, which was simply ignored. Fixes openssl#23373 Reviewed-by: Tom Cosgrove <[email protected]> Reviewed-by: Tomas Mraz <[email protected]> (Merged from openssl#23374)
kassane · Jan 25, 2024 · ea6268c · ea6268c
1 parent 8a85df7
commit ea6268c
Show file tree

Hide file tree

Showing 2 changed files with 51 additions and 1 deletion.
diff --git a/crypto/params_from_text.c b/crypto/params_from_text.c
@@ -115,7 +115,13 @@ static int prepare_from_text(const OSSL_PARAM *paramdefs, const char *key,
         break;
     case OSSL_PARAM_OCTET_STRING:
         if (*ishex) {
-            *buf_n = strlen(value) >> 1;
+            size_t hexdigits = strlen(value);
+            if ((hexdigits % 2) != 0) {
+                /* We don't accept an odd number of hex digits */
+                ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_ODD_NUMBER_OF_DIGITS);
+                return 0;
+            }
+            *buf_n = hexdigits >> 1;
         } else {
             *buf_n = value_n;
         }

diff --git a/test/params_test.c b/test/params_test.c
@@ -15,6 +15,7 @@
 #include <string.h>
 #include <openssl/bn.h>
 #include <openssl/core.h>
+#include <openssl/err.h>
 #include <openssl/params.h>
 #include "internal/numbers.h"
 #include "internal/nelem.h"
@@ -558,6 +559,7 @@ static const OSSL_PARAM params_from_text[] = {
     /* Arbitrary size buffer.  Make sure the result fits in a long */
     OSSL_PARAM_DEFN("num", OSSL_PARAM_INTEGER, NULL, 0),
     OSSL_PARAM_DEFN("unum", OSSL_PARAM_UNSIGNED_INTEGER, NULL, 0),
+    OSSL_PARAM_DEFN("octets", OSSL_PARAM_OCTET_STRING, NULL, 0),
     OSSL_PARAM_END,
 };
 
@@ -655,14 +657,56 @@ static int check_int_from_text(const struct int_from_text_test_st a)
     return a.expected_res;
 }
 
+static int check_octetstr_from_hexstr(void)
+{
+    OSSL_PARAM param;
+    static const char *values[] = { "", "F", "FF", "FFF", "FFFF", NULL };
+    int i;
+    int errcnt = 0;
+
+    /* Test odd vs even number of hex digits */
+    for (i = 0; values[i] != NULL; i++) {
+        int expected = (strlen(values[i]) % 2) != 1;
+        int result;
+
+        ERR_clear_error();
+        memset(&param, 0, sizeof(param));
+        if (expected)
+            result =
+                TEST_true(OSSL_PARAM_allocate_from_text(&param,
+                                                        params_from_text,
+                                                        "hexoctets", values[i], 0,
+                                                        NULL));
+        else
+            result =
+                TEST_false(OSSL_PARAM_allocate_from_text(&param,
+                                                         params_from_text,
+                                                         "hexoctets", values[i], 0,
+                                                         NULL));
+        if (!result) {
+            TEST_error("unexpected OSSL_PARAM_allocate_from_text() %s for 'octets' \"%s\"",
+                       (expected ? "failure" : "success"), values[i]);
+            errcnt++;
+        }
+        OPENSSL_free(param.data);
+    }
+    return errcnt == 0;
+}
+
 static int test_allocate_from_text(int i)
 {
     return check_int_from_text(int_from_text_test_cases[i]);
 }
 
+static int test_more_allocate_from_text(void)
+{
+    return check_octetstr_from_hexstr();
+}
+
 int setup_tests(void)
 {
     ADD_ALL_TESTS(test_case, OSSL_NELEM(test_cases));
     ADD_ALL_TESTS(test_allocate_from_text, OSSL_NELEM(int_from_text_test_cases));
+    ADD_TEST(test_more_allocate_from_text);
     return 1;
 }