NSS Sample Code Common: Utilities
This is a library of utilities used by many of the samples. This code shows the following:
- Extract seed from noise file
- Read DER encoding from a file
- Extract the password from a text file
- Get the module password
- Print as ascii or hexadecimal
Sample Code
#include <prlog.h>
#include <termios.h>
#include <base64.h>
#include <unistd.h>
#include <sys/stat.h>
#include <prprf.h>
#include "util.h"
/*
* These utility functions are adapted from those found in
* the sectool library used by the NSS security tools and
* other NSS test applications.
*/
/*
* Newline
*/
static void Newline(PRFileDesc* out) {
PR_fprintf(out, "\n");
}
/*
* PrintAsAscii
*/
void PrintAsAscii(PRFileDesc* out, const unsigned char *data, unsigned int len)
{
char *b64Data = NULL;
b64Data = BTOA_DataToAscii(data, len);
PR_fprintf(out, "%s", b64Data);
PR_fprintf(out, "\n");
if (b64Data) {
PORT_Free(b64Data);
}
}
/*
* PrintAsHex
*/
void PrintAsHex(PRFileDesc* out, const unsigned char *data, unsigned int len)
{
unsigned i;
int column;
unsigned int limit = 15;
unsigned int level = 1;
column = level;
if (!len) {
PR_fprintf(out, "(empty)\n");
return;
}
for (i = 0; i < len; i++) {
if (i != len - 1) {
PR_fprintf(out, "%02x:", data[i]);
column += 3;
} else {
PR_fprintf(out, "%02x", data[i]);
column += 2;
break;
}
if (column > 76 || (i % 16 == limit)) {
Newline(out);
column = level;
limit = i % 16;
}
}
if (column != level) {
Newline(out);
}
}
/*
* GetDigit
*/
int GetDigit(char c)
{
if (c == 0) {
return -1;
}
if (c <= '9' && c >= '0') {
return c - '0';
}
if (c <= 'f' && c >= 'a') {
return c - 'a' + 0xa;
}
if (c <= 'F' && c >= 'A') {
return c - 'A' + 0xa;
}
return -1;
}
/*
* HexToBuf
*/
int HexToBuf(unsigned char *inString, SECItem *outbuf, PRBool isHexData)
{
int len = strlen(inString);
int outLen = len+1/2;
int trueLen = 0;
int digit1, digit2;
outbuf->data = isHexData
? PORT_Alloc(outLen)
: PORT_Alloc(len);
if (!outbuf->data) {
return -1;
}
if (isHexData) {
while (*inString) {
if ((*inString == '\n') || (*inString == ':')) {
inString++;
continue;
}
digit1 = GetDigit(*inString++);
digit2 = GetDigit(*inString++);
if ((digit1 == -1) || (digit2 == -1)) {
PORT_Free(outbuf->data);
outbuf->data = NULL;
return -1;
}
outbuf->data[trueLen++] = digit1 << 4 | digit2;
}
} else {
while (*inString) {
if (*inString == '\n') {
inString++;
continue;
}
outbuf->data[trueLen++] = *inString++;
}
outbuf->data[trueLen] = '\0';
trueLen = trueLen-1;
}
outbuf->len = trueLen;
return 0;
}
/*
* FileToItem
*/
SECStatus FileToItem(SECItem *dst, PRFileDesc *src)
{
PRFileInfo info;
PRInt32 numBytes;
PRStatus prStatus;
prStatus = PR_GetOpenFileInfo(src, &info);
if (prStatus != PR_SUCCESS) {
return SECFailure;
}
dst->data = 0;
if (SECITEM_AllocItem(NULL, dst, info.size)) {
numBytes = PR_Read(src, dst->data, info.size);
if (numBytes == info.size) {
return SECSuccess;
}
}
SECITEM_FreeItem(dst, PR_FALSE);
dst->data = NULL;
return SECFailure;
}
/*
* echoOff
*/
static void echoOff(int fd)
{
if (isatty(fd)) {
struct termios tio;
tcgetattr(fd, &tio);
tio.c_lflag &= ~ECHO;
tcsetattr(fd, TCSAFLUSH, &tio);
}
}
/*
* echoOn
*/
static void echoOn(int fd)
{
if (isatty(fd)) {
struct termios tio;
tcgetattr(fd, &tio);
tio.c_lflag |= ECHO;
tcsetattr(fd, TCSAFLUSH, &tio);
}
}
/*
* CheckPassword
*/
PRBool CheckPassword(char *cp)
{
int len;
char *end;
len = PORT_Strlen(cp);
if (len < 8) {
return PR_FALSE;
}
end = cp + len;
while (cp < end) {
unsigned char ch = *cp++;
if (!((ch >= 'A') && (ch <= 'Z')) &&
!((ch >= 'a') && (ch <= 'z'))) {
return PR_TRUE;
}
}
return PR_FALSE;
}
/*
* GetPassword
*/
char* GetPassword(FILE *input, FILE *output, char *prompt,
PRBool (*ok)(char *))
{
char phrase[200] = {'\0'};
int infd = fileno(input);
int isTTY = isatty(infd);
for (;;) {
/* Prompt for password */
if (isTTY) {
fprintf(output, "%s", prompt);
fflush (output);
echoOff(infd);
}
fgets(phrase, sizeof(phrase), input);
if (isTTY) {
fprintf(output, "\n");
echoOn(infd);
}
/* stomp on newline */
phrase[PORT_Strlen(phrase)-1] = 0;
/* Validate password */
if (!(*ok)(phrase)) {
if (!isTTY) return 0;
fprintf(output, "Password must be at least 8 characters long with one or more\n");
fprintf(output, "non-alphabetic characters\n");
continue;
}
return (char*) PORT_Strdup(phrase);
}
}
/*
* FilePasswd extracts the password from a text file
*
* Storing passwords is often used with server environments
* where prompting the user for a password or requiring it
* to be entered in the command line is not a feasible option.
*
* This function supports password extraction from files with
* multiple passwords, one for each token. In the single password
* case a line would just have the password whereas in the multi-
* password variant they could be of the form
*
* token_1_name:its_password
* token_2_name:its_password
*
*/
char *FilePasswd(PK11SlotInfo *slot, PRBool retry, void *arg)
{
char* phrases, *phrase;
PRFileDesc *fd;
PRInt32 nb;
char *pwFile = arg;
int i;
const long maxPwdFileSize = 4096;
char* tokenName = NULL;
int tokenLen = 0;
if (!pwFile)
return 0;
if (retry) {
return 0; /* no good retrying - the file contents will be the same */
}
phrases = PORT_ZAlloc(maxPwdFileSize);
if (!phrases) {
return 0; /* out of memory */
}
fd = PR_Open(pwFile, PR_RDONLY, 0);
if (!fd) {
fprintf(stderr, "No password file \"%s\" exists.\n", pwFile);
PORT_Free(phrases);
return NULL;
}
nb = PR_Read(fd, phrases, maxPwdFileSize);
PR_Close(fd);
if (nb == 0) {
fprintf(stderr,"password file contains no data\n");
PORT_Free(phrases);
return NULL;
}
if (slot) {
tokenName = PK11_GetTokenName(slot);
if (tokenName) {
tokenLen = PORT_Strlen(tokenName);
}
}
i = 0;
do {
int startphrase = i;
int phraseLen;
/* handle the Windows EOL case */
while (phrases[i] != '\r' && phrases[i] != '\n' && i < nb) i++;
/* terminate passphrase */
phrases[i++] = '\0';
/* clean up any EOL before the start of the next passphrase */
while ( (i<nb) analyze="" char="" current="" getmodulepassword="" if="" int="" now="" passphrase="" phrase="&phrases[startphrase];" phraselen="" pk11slotinfo="" pwdata="=" pwdata-="" retry="" return="" secupwdata="" the="" void="" while="">source != PW_NONE) {
PR_fprintf(PR_STDERR, "Incorrect password/PIN entered.\n");
return NULL;
}
switch (pwdata->source) {
case PW_NONE:
sprintf(prompt, "Enter Password or Pin for \"%s\":",
PK11_GetTokenName(slot));
return GetPassword(stdin, stdout, prompt, CheckPassword);
case PW_FROMFILE:
pw = FilePasswd(slot, retry, pwdata->data);
pwdata->source = PW_PLAINTEXT;
pwdata->data = PL_strdup(pw);
return pw;
case PW_PLAINTEXT:
return PL_strdup(pwdata->data);
default:
break;
}
PR_fprintf(PR_STDERR, "Password check failed: No password found.\n");
return NULL;
}
/*
* GenerateRandom
*/
SECStatus GenerateRandom(unsigned char *rbuf, int rsize)
{
char meter[] = {
"\r| |" };
int fd, count;
int c;
SECStatus rv = SECSuccess;
cc_t orig_cc_min;
cc_t orig_cc_time;
tcflag_t orig_lflag;
struct termios tio;
fprintf(stderr, "To generate random numbers, "
"continue typing until the progress meter is full:\n\n");
fprintf(stderr, "%s", meter);
fprintf(stderr, "\r|");
/* turn off echo on stdin & return on 1 char instead of NL */
fd = fileno(stdin);
tcgetattr(fd, &tio);
orig_lflag = tio.c_lflag;
orig_cc_min = tio.c_cc[VMIN];
orig_cc_time = tio.c_cc[VTIME];
tio.c_lflag &= ~ECHO;
tio.c_lflag &= ~ICANON;
tio.c_cc[VMIN] = 1;
tio.c_cc[VTIME] = 0;
tcsetattr(fd, TCSAFLUSH, &tio);
/* Get random noise from keyboard strokes */
count = 0;
while (count < rsize) {
c = getc(stdin);
if (c == EOF) {
rv = SECFailure;
break;
}
*(rbuf + count) = c;
if (count == 0 || c != *(rbuf + count -1)) {
count++;
fprintf(stderr, "*");
}
}
rbuf[count] = '\0';
fprintf(stderr, "\n\nFinished. Press enter to continue: ");
while ((c = getc(stdin)) != '\n' && c != EOF)
;
if (c == EOF)
rv = SECFailure;
fprintf(stderr, "\n");
/* set back termio the way it was */
tio.c_lflag = orig_lflag;
tio.c_cc[VMIN] = orig_cc_min;
tio.c_cc[VTIME] = orig_cc_time;
tcsetattr(fd, TCSAFLUSH, &tio);
return rv;
}
/*
* SeedFromNoiseFile
*/
SECStatus SeedFromNoiseFile(const char *noiseFileName)
{
char buf[2048];
PRFileDesc *fd;
PRInt32 count;
fd = PR_Open(noiseFileName, PR_RDONLY, 0);
if (!fd) {
fprintf(stderr, "failed to open noise file.");
return SECFailure;
}
do {
count = PR_Read(fd,buf,sizeof(buf));
if (count > 0) {
PK11_RandomUpdate(buf,count);
}
} while (count > 0);
PR_Close(fd);
return SECSuccess;
}
/*
* FileSize
*/
long FileSize(const char* filename)
{
struct stat stbuf;
stat(filename, &stbuf);
return stbuf.st_size;
}
/*
* ReadDERFromFile
*/
SECStatus ReadDERFromFile(SECItem *der, const char *inFileName, PRBool ascii)
{
SECStatus rv = SECSuccess;
PRFileDesc *inFile = NULL;
inFile = PR_Open(inFileName, PR_RDONLY, 0);
if (!inFile) {
PR_fprintf(PR_STDERR, "Failed to open file \"%s\" (%ld, %ld).\n",
inFileName, PR_GetError(), PR_GetOSError());
rv = SECFailure;
goto cleanup;
}
if (ascii) {
/* First convert ascii to binary */
SECItem filedata;
char *asc, *body;
/* Read in ascii data */
rv = FileToItem(&filedata, inFile);
asc = (char *)filedata.data;
if (!asc) {
PR_fprintf(PR_STDERR, "unable to read data from input file\n");
rv = SECFailure;
goto cleanup;
}
/* check for headers and trailers and remove them */
if ((body = strstr(asc, "-----BEGIN")) != NULL) {
char *trailer = NULL;
asc = body;
body = PORT_Strchr(body, '\n');
if (!body)
body = PORT_Strchr(asc, '\r'); /* maybe this is a MAC file */
if (body)
trailer = strstr(++body, "-----END");
if (trailer != NULL) {
*trailer = '\0';
} else {
PR_fprintf(PR_STDERR, "input has header but no trailer\n");
PORT_Free(filedata.data);
rv = SECFailure;
goto cleanup;
}
} else {
body = asc;
}
/* Convert to binary */
rv = ATOB_ConvertAsciiToItem(der, body);
if (rv) {
PR_fprintf(PR_STDERR, "error converting ascii to binary %s\n",
PORT_GetError());
PORT_Free(filedata.data);
rv = SECFailure;
goto cleanup;
}
PORT_Free(filedata.data);
} else {
/* Read in binary der */
rv = FileToItem(der, inFile);
if (rv) {
PR_fprintf(PR_STDERR, "error converting der \n");
rv = SECFailure;
}
}
cleanup:
if (inFile) {
PR_Close(inFile);
}
return rv;
}
</nb)>