FYI: We "temporarily" implemented this get SSL version string helper function in the Directory Server code (slapd/ssl.c).  We'd like to replace this function with the official API provided by NSS.

/* 
 * If non NULL buf and positive bufsize is given,
 * the memory is used to store the version string.
 * Otherwise, the memory for the string is allocated.
 * The latter case, caller is responsible to free it.
 */
char *
slapi_getSSLVersion_str(PRUint16 vnum, char *buf, size_t bufsize)
{
    char *vstr = buf;
    if (vnum >= SSL_LIBRARY_VERSION_3_0) {
        if (vnum == SSL_LIBRARY_VERSION_3_0) { /* SSL3 */
            if (buf && bufsize) {
                PR_snprintf(buf, bufsize, "SSL3");
            } else {
                vstr = slapi_ch_smprintf("SSL3");
            }
        } else { /* TLS v X.Y */
            const char *TLSFMT = "TLS%d.%d";
            int minor_offset = 0; /* e.g. 0x0401 -> TLS v 2.1, not 2.0 */

            if ((vnum & SSL_LIBRARY_VERSION_3_0) == SSL_LIBRARY_VERSION_3_0) {
                minor_offset = 1; /* e.g. 0x0301 -> TLS v 1.0, not 1.1 */
            }
            if (buf && bufsize) {
                PR_snprintf(buf, bufsize, TLSFMT, (vnum >> 8) - 2, (vnum & 0xff) - minor_offset);
            } else {
                vstr = slapi_ch_smprintf(TLSFMT, (vnum >> 8) - 2, (vnum & 0xff) - minor_offset);
            }
        }
    } else if (vnum == SSL_LIBRARY_VERSION_2) { /* SSL2 */
        if (buf && bufsize) {
            PR_snprintf(buf, bufsize, "SSL2");
        } else {
            vstr = slapi_ch_smprintf("SSL2");
        }
    } else {
        if (buf && bufsize) {
            PR_snprintf(buf, bufsize, "Unknown SSL version: 0x%x", vnum);
        } else {
            vstr = slapi_ch_smprintf("Unknown SSL version: 0x%x", vnum);
        }
    }
    return vstr;
}

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Still an issue in Fedora rawhide.

This package has changed ownership in the Fedora Package Database.  Reassigning to the new owner of this component.

NSSUTIL_GetVersion
NSS_GetVersion
NSSSSL_GetVersion
NSSSMIME_GetVersion
PR_GetVersion

These functions have been available since NSPR 4.8.9 and NSS 3.13

(In reply to Kai Engert (:kaie) from comment #6)
> NSSUTIL_GetVersion
> NSS_GetVersion
> NSSSSL_GetVersion
> NSSSMIME_GetVersion
> PR_GetVersion
> 
> These functions have been available since NSPR 4.8.9 and NSS 3.13

How are the above functions related to the problem described in comment #0 and comment #1 (translation of SSL version enumeration constants to strings)?

I misinterpreted the request, I thought you'd like a version string for the NSS library version.

Feature enhancement requests liks this should be reported upstream, where the software development takes place (not in Fedora where we're mostly doing packaging).

still haven't been requested upstream.

(In reply to Kai Engert (:kaie) from comment #9)
> still haven't been requested upstream.

I believe this was requested 9 years ago:

https://bugzilla.mozilla.org/480174

I thought that mozilla bug was for fedora bug 917134.

Is this bug a duplicate of bug 917134 ?

Sorry, fedora bug 917133

Not really a duplicate but very similar (one is about cipher-suite names and one about SSL versions).  Anyway, I do not think that creating additional upstream requests is going to help us much...

I doubt such API is really useful.  As those codepoints are standardized in TLS, applications can safely rely on it.  Also the format of version numvers depends on application: some might want "SSL3" and the others might want "ssl3.0".  I'd rather leave this choice to applications.