2 files changed, 42 insertions, 52 deletions

diff --git a/src/lib/libcrypto/ts/ts_rsp_sign.c b/src/lib/libcrypto/ts/ts_rsp_sign.c
index a6ce1796c6..b0f023c9d2 100644
--- a/src/lib/libcrypto/ts/ts_rsp_sign.c
+++ b/src/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;
-        int rv;
+        char *p = genTime_str;
+        char *p_end = genTime_str + sizeof(genTime_str);
 
         if (precision > TS_MAX_CLOCK_PRECISION_DIGITS)
                 goto err;
@@ -970,13 +970,18 @@ TS_RESP_set_genTime_with_precision(ASN1_GENERALIZEDTIME *asn1_time,
          * meet the rfc3161 requirement: "GeneralizedTime syntax can include 
          * fraction-of-second details". 
          */                   
-        if (precision > 0) {
-                rv = snprintf(genTime_str, sizeof(genTime_str),
-                          "%04d%02d%02d%02d%02d%02d.%ldZ",
+        p += BIO_snprintf(p, p_end - p,
+                          "%04d%02d%02d%02d%02d%02d",
                           tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday, 
-                          tm->tm_hour, tm->tm_min, tm->tm_sec, usec);
-                if (rv == -1 || rv >= sizeof(genTime_str))
-                        goto err;
+                          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);
+
                 /* 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 
@@ -990,24 +995,14 @@ 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. */
-                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;
-        }
+                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';
 
         /* Now call OpenSSL to check and set our genTime value */
         if (!asn1_time && !(asn1_time = M_ASN1_GENERALIZEDTIME_new()))
diff --git a/src/lib/libssl/src/crypto/ts/ts_rsp_sign.c b/src/lib/libssl/src/crypto/ts/ts_rsp_sign.c
index a6ce1796c6..b0f023c9d2 100644
--- a/src/lib/libssl/src/crypto/ts/ts_rsp_sign.c
+++ b/src/lib/libssl/src/crypto/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;
-        int rv;
+        char *p = genTime_str;
+        char *p_end = genTime_str + sizeof(genTime_str);
 
         if (precision > TS_MAX_CLOCK_PRECISION_DIGITS)
                 goto err;
@@ -970,13 +970,18 @@ TS_RESP_set_genTime_with_precision(ASN1_GENERALIZEDTIME *asn1_time,
          * meet the rfc3161 requirement: "GeneralizedTime syntax can include 
          * fraction-of-second details". 
          */                   
-        if (precision > 0) {
-                rv = snprintf(genTime_str, sizeof(genTime_str),
-                          "%04d%02d%02d%02d%02d%02d.%ldZ",
+        p += BIO_snprintf(p, p_end - p,
+                          "%04d%02d%02d%02d%02d%02d",
                           tm->tm_year + 1900, tm->tm_mon + 1, tm->tm_mday, 
-                          tm->tm_hour, tm->tm_min, tm->tm_sec, usec);
-                if (rv == -1 || rv >= sizeof(genTime_str))
-                        goto err;
+                          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);
+
                 /* 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 
@@ -990,24 +995,14 @@ 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. */
-                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;
-        }
+                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';
 
         /* Now call OpenSSL to check and set our genTime value */
         if (!asn1_time && !(asn1_time = M_ASN1_GENERALIZEDTIME_new()))