There was a bug in the OTA library, addressed by the following post: 
However, a bug remains. As written the FSM for the OTA library will not properly progress to other archives, even though the comparison is correct. The fix is to do the following:
1. In OtaLib.c, comment out the line, below:
case OTA_STATE_CHECK_ARCHIVE_NEW_UPDATE:
{
uint8_t *pVersionFileName;
_SlOtaLibTrace(("OTA_run: CdnClient_GetNextDirFile\r\n"));
pOtaLib->pOtaFileName = CdnClient_GetNextDirFile(pCdnClient, &pOtaLib->OtaFileSize);
/* check if last file in the list, still without tar file */
if( pOtaLib->pOtaFileName == NULL)
{
/* tar file not found, return no updates */
_SlOtaLibTrace(("OTA_run: ERROR CdnClient_ReqOtaDir - tar not found, no updates\r\n"));
pOtaLib->ConsecutiveOtaErrors = 0;
pOtaLib->State = OTA_STATE_IDLE;
_OtaCleanToIdle(pOtaLib);
return OTA_RUN_STATUS_NO_UPDATES;
}
_SlOtaLibTrace(("OTA_run: CdnClient_GetNextDirFile: file=%s, size=%ld\r\n", pOtaLib->pOtaFileName, pOtaLib->OtaFileSize));
if (strstr((const char *)pOtaLib->pOtaFileName, ".tar") == NULL)
{
_SlOtaLibTrace(("OTA_run: WARNING, not a tar file, filename=%s\r\n", pOtaLib->pOtaFileName));
/* Stay on state, check next file version */
pOtaLib->State = OTA_STATE_CHECK_ARCHIVE_NEW_UPDATE;
return OTA_RUN_STATUS_CONTINUE;
}
/* continue anyway, user app can override this decision */
// COMMENT THIS LINE OUT
//pOtaLib->State = OTA_STATE_REQ_FILE_URL; <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
/* Init the Tar parser module */
OtaArchive_init(&pOtaLib->OtaArchive);
2. Add in OTA_set:
case EXTLIB_OTA_SET_OPT_ACCEPT_UPDATE:
/* check if after OTA_STATE_CHECK_ARCHIVE_NEW_UPDATE state */
if (pOtaLib->State != OTA_STATE_CHECK_ARCHIVE_NEW_UPDATE)
{
_SlOtaLibTrace(("OTA_set: ERROR EXTLIB_OTA_SET_OPT_ACCEPT_UPDATE in wrong state = %d\r\n", pOtaLib->State));
return OTA_OPT_ERROR_WRONG_STATE;
}
pOtaLib->State = OTA_STATE_REQ_FILE_URL;
break;
3. If you wish to DECLINE an update, don't call Ota_set, just do nothing.
These changes will enable the FSM to progress.
Happy to send a patch if there is a mechanism to do that.
