Improve ASN1_TIME_print documentation and output

This adds missing GMT indication when printing the local time as
it is converted to the UTC timezone before printing.

Also fixing the fractional seconds printing on EBCDIC platforms.

Fixes #26313

Reviewed-by: Todd Short <todd.short@me.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/26344)

diff --git a/crypto/asn1/a_time.c b/crypto/asn1/a_time.c
index 7dfbc5faabd15510b39716eab6c65b7611f4e526..be19937638b9ddcf9cf46f2c85fea36205c6a9d2 100644 (file)
--- a/crypto/asn1/a_time.c
+++ b/crypto/asn1/a_time.c
@@ -490,9 +490,9 @@ int ASN1_TIME_print_ex(BIO *bp, const ASN1_TIME *tm, unsigned long flags)
 int ossl_asn1_time_print_ex(BIO *bp, const ASN1_TIME *tm, unsigned long flags)
 {
     char *v;
-    int gmt = 0, l;
+    int l;
     struct tm stm;
-    const char upper_z = 0x5A, period = 0x2E;
+    const char period = 0x2E;
 
     /* ossl_asn1_time_to_tm will check the time type */
     if (!ossl_asn1_time_to_tm(&stm, tm))
@@ -500,8 +500,6 @@ int ossl_asn1_time_print_ex(BIO *bp, const ASN1_TIME *tm, unsigned long flags)
 
     l = tm->length;
     v = (char *)tm->data;
-    if (v[l - 1] == upper_z)
-        gmt = 1;
 
     if (tm->type == V_ASN1_GENERALIZEDTIME) {
         char *f = NULL;
@@ -512,39 +510,36 @@ int ossl_asn1_time_print_ex(BIO *bp, const ASN1_TIME *tm, unsigned long flags)
          * 'fraction point' in a GeneralizedTime string.
          */
         if (tm->length > 15 && v[14] == period) {
-            f = &v[14];
-            f_len = 1;
-            while (14 + f_len < l && ossl_ascii_isdigit(f[f_len]))
+            /* exclude the . itself */
+            f = &v[15];
+            f_len = 0;
+            while (15 + f_len < l && ossl_ascii_isdigit(f[f_len]))
                 ++f_len;
         }
 
-        if ((flags & ASN1_DTFLGS_TYPE_MASK) == ASN1_DTFLGS_ISO8601) {
-            return BIO_printf(bp, "%4d-%02d-%02d %02d:%02d:%02d%.*s%s",
-                          stm.tm_year + 1900, stm.tm_mon + 1,
-                          stm.tm_mday, stm.tm_hour,
-                          stm.tm_min, stm.tm_sec, f_len, f,
-                          (gmt ? "Z" : "")) > 0;
-        }
-        else {
-            return BIO_printf(bp, "%s %2d %02d:%02d:%02d%.*s %d%s",
-                          _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour,
-                          stm.tm_min, stm.tm_sec, f_len, f, stm.tm_year + 1900,
-                          (gmt ? " GMT" : "")) > 0;
+        if (f_len > 0) {
+            if ((flags & ASN1_DTFLGS_TYPE_MASK) == ASN1_DTFLGS_ISO8601) {
+                return BIO_printf(bp, "%4d-%02d-%02d %02d:%02d:%02d.%.*sZ",
+                                  stm.tm_year + 1900, stm.tm_mon + 1,
+                                  stm.tm_mday, stm.tm_hour,
+                                  stm.tm_min, stm.tm_sec, f_len, f) > 0;
+            } else {
+                return BIO_printf(bp, "%s %2d %02d:%02d:%02d.%.*s %d GMT",
+                                  _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour,
+                                  stm.tm_min, stm.tm_sec, f_len, f,
+                                  stm.tm_year + 1900) > 0;
+            }
         }
-    } else {
-        if ((flags & ASN1_DTFLGS_TYPE_MASK) == ASN1_DTFLGS_ISO8601) {
-            return BIO_printf(bp, "%4d-%02d-%02d %02d:%02d:%02d%s",
+    }
+    if ((flags & ASN1_DTFLGS_TYPE_MASK) == ASN1_DTFLGS_ISO8601) {
+        return BIO_printf(bp, "%4d-%02d-%02d %02d:%02d:%02dZ",
                           stm.tm_year + 1900, stm.tm_mon + 1,
                           stm.tm_mday, stm.tm_hour,
-                          stm.tm_min, stm.tm_sec,
-                          (gmt ? "Z" : "")) > 0;
-        }
-        else {
-            return BIO_printf(bp, "%s %2d %02d:%02d:%02d %d%s",
+                          stm.tm_min, stm.tm_sec) > 0;
+    } else {
+        return BIO_printf(bp, "%s %2d %02d:%02d:%02d %d GMT",
                           _asn1_mon[stm.tm_mon], stm.tm_mday, stm.tm_hour,
-                          stm.tm_min, stm.tm_sec, stm.tm_year + 1900,
-                          (gmt ? " GMT" : "")) > 0;
-        }
+                          stm.tm_min, stm.tm_sec, stm.tm_year + 1900) > 0;
     }
 }
 

diff --git a/doc/man3/ASN1_TIME_set.pod b/doc/man3/ASN1_TIME_set.pod
index 66d9fefe1af6e5b2aa6a9adfdeb234b66723442e..1efe305e00d3c4139444fba7e316e04d04941358 100644 (file)
--- a/doc/man3/ASN1_TIME_set.pod
+++ b/doc/man3/ASN1_TIME_set.pod
@@ -102,8 +102,8 @@ functions check the syntax of the time structure I<s>.
 
 The ASN1_TIME_print(), ASN1_UTCTIME_print() and ASN1_GENERALIZEDTIME_print()
 functions print the time structure I<s> to BIO I<b> in human readable
-format. It will be of the format MMM DD HH:MM:SS YYYY [GMT], for example
-"Feb  3 00:55:52 2015 GMT", which does not include a newline.
+format. It will be of the format MMM DD HH:MM:SS[.s*] YYYY GMT, for example
+"Feb E<32>3 00:55:52 2015 GMT", which does not include a newline.
 If the time structure has invalid format it prints out "Bad time value" and
 returns an error. The output for generalized time may include a fractional part
 following the second.
@@ -179,6 +179,10 @@ starting with B<ASN1_UTCTIME> and B<ASN1_GENERALIZEDTIME> act only on that
 specific time format. The functions starting with B<ASN1_TIME> will operate on
 either format.
 
+Users familiar with RFC822 should note that when specifying the flag
+B<ASN1_DTFLGS_RFC822> the year will be formatted as documented above,
+i.e., using 4 digits, not 2 as specified in RFC822.
+
 =head1 BUGS
 
 ASN1_TIME_print(), ASN1_UTCTIME_print() and ASN1_GENERALIZEDTIME_print() do