replace some bio_snprintf crazy with regular snprintf.

beck had a diff to convert to strftime, but it's easier to verify this
is functionally the same. ok beck.

1 files changed, 26 insertions, 21 deletions

diff --git a/lib/libcrypto/ts/ts_rsp_sign.c b/lib/libcrypto/ts/ts_rsp_sign.c
index b0f023c9d2f..a6ce1796c62 100644
--- a/lib/libcrypto/ts/ts_rsp_sign.c
+++ b/lib/libcrypto/ts/ts_rsp_sign.c
@@ -953,8 +953,8 @@ TS_RESP_set_genTime_with_precision(ASN1_GENERALIZEDTIME *asn1_time,
 	time_t time_sec = (time_t) sec;
 	struct tm *tm = NULL;	
 	char genTime_str[17 + TS_MAX_CLOCK_PRECISION_DIGITS];
-	char *p = genTime_str;
-	char *p_end = genTime_str + sizeof(genTime_str);
+	char *p;
+	int rv;
 
 	if (precision > TS_MAX_CLOCK_PRECISION_DIGITS)
 		goto err;
@@ -970,18 +970,13 @@ TS_RESP_set_genTime_with_precision(ASN1_GENERALIZEDTIME *asn1_time,
 	 * meet the rfc3161 requirement: "GeneralizedTime syntax can include 
 	 * fraction-of-second details". 
 	 */                   
-	p += BIO_snprintf(p, p_end - p,
-			  "%04d%02d%02d%02d%02d%02d",
+	if (precision > 0) {
+		rv = snprintf(genTime_str, sizeof(genTime_str),
+			  "%04d%02d%02d%02d%02d%02d.%ldZ",
 			  tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday, 
-			  tm->tm_hour, tm->tm_min, tm->tm_sec);
-	if (precision > 0)
-	{
-		/* Add fraction of seconds (leave space for dot and null). */
-		BIO_snprintf(p, 2 + precision, ".%ld", usec);
-		/* We cannot use the snprintf return value, 
-		   because it might have been truncated. */
-		p += strlen(p);
-
+			  tm->tm_hour, tm->tm_min, tm->tm_sec, usec);
+		if (rv == -1 || rv >= sizeof(genTime_str))
+			goto err;
 		/* To make things a bit harder, X.690 | ISO/IEC 8825-1 provides
 		   the following restrictions for a DER-encoding, which OpenSSL
 		   (specifically ASN1_GENERALIZEDTIME_check() function) doesn't 
@@ -995,14 +990,24 @@ TS_RESP_set_genTime_with_precision(ASN1_GENERALIZEDTIME *asn1_time,
 		   omitted." */
 		/* Remove trailing zeros. The dot guarantees the exit
 		   condition of this loop even if all the digits are zero. */
-		while (*--p == '0')
-			/* empty */;
-		/* p points to either the dot or the last non-zero digit. */
-		if (*p != '.') ++p;
-		}
-	/* Add the trailing Z and the terminating null. */
-	*p++ = 'Z';
-	*p++ = '\0';
+		p = strchr(genTime_str, 'Z');
+		p--; /* move back in front of Z */
+		/* pass over 0s */
+		while (*p == '0')
+			p--;
+		/* if we're not at . we're at an interesting digit */
+		if (*p != '.')
+			p++;
+		*p++ = 'Z';
+		*p = 0;
+	} else {
+		rv = snprintf(genTime_str, sizeof(genTime_str),
+			  "%04d%02d%02d%02d%02d%02dZ",
+			  tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday, 
+			  tm->tm_hour, tm->tm_min, tm->tm_sec);
+		if (rv == -1 || rv >= sizeof(genTime_str))
+			goto err;
+	}
 
 	/* Now call OpenSSL to check and set our genTime value */
 	if (!asn1_time && !(asn1_time = M_ASN1_GENERALIZEDTIME_new()))