tor-browser

p7verify.c (7895B)

---

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
* p7verify -- A command to do a verification of a *detached* pkcs7 signature.
*/

#include "nspr.h"
#include "secutil.h"
#include "plgetopt.h"
#include "secpkcs7.h"
#include "cert.h"
#include "certdb.h"
#include "secoid.h"
#include "sechash.h" /* for HASH_GetHashObject() */
#include "nss.h"

#if defined(XP_UNIX)
#include <unistd.h>
#endif

#include <stdio.h>
#include <string.h>

#if (defined(XP_WIN) && !defined(WIN32)) || (defined(__sun) && !defined(SVR4))
extern int fread(char *, size_t, size_t, FILE *);
extern int fprintf(FILE *, char *, ...);
#endif

static int
DigestFile(unsigned char *digest, unsigned int *len, unsigned int maxLen,
          FILE *inFile, HASH_HashType hashType)
{
   int nb;
   unsigned char ibuf[4096];
   const SECHashObject *hashObj;
   void *hashcx;

   hashObj = HASH_GetHashObject(hashType);

   hashcx = (*hashObj->create)();
   if (hashcx == NULL)
       return -1;

   (*hashObj->begin)(hashcx);

   for (;;) {
       if (feof(inFile))
           break;
       nb = fread(ibuf, 1, sizeof(ibuf), inFile);
       if (nb != sizeof(ibuf)) {
           if (nb == 0) {
               if (ferror(inFile)) {
                   PORT_SetError(SEC_ERROR_IO);
                   (*hashObj->destroy)(hashcx, PR_TRUE);
                   return -1;
               }
               /* eof */
               break;
           }
       }
       (*hashObj->update)(hashcx, ibuf, nb);
   }

   (*hashObj->end)(hashcx, digest, len, maxLen);
   (*hashObj->destroy)(hashcx, PR_TRUE);

   return 0;
}

static void
Usage(char *progName)
{
   fprintf(stderr,
           "Usage:  %s -c content -s signature [-d dbdir] [-u certusage]\n",
           progName);
   fprintf(stderr, "%-20s content file that was signed\n",
           "-c content");
   fprintf(stderr, "%-20s file containing signature for that content\n",
           "-s signature");
   fprintf(stderr,
           "%-20s Key/Cert database directory (default is ~/.netscape)\n",
           "-d dbdir");
   fprintf(stderr, "%-20s Define the type of certificate usage (default is certUsageEmailSigner)\n",
           "-u certusage");
   fprintf(stderr, "%-25s  0 - certUsageSSLClient\n", " ");
   fprintf(stderr, "%-25s  1 - certUsageSSLServer\n", " ");
   fprintf(stderr, "%-25s  2 - certUsageSSLServerWithStepUp\n", " ");
   fprintf(stderr, "%-25s  3 - certUsageSSLCA\n", " ");
   fprintf(stderr, "%-25s  4 - certUsageEmailSigner\n", " ");
   fprintf(stderr, "%-25s  5 - certUsageEmailRecipient\n", " ");
   fprintf(stderr, "%-25s  6 - certUsageObjectSigner\n", " ");
   fprintf(stderr, "%-25s  7 - certUsageUserCertImport\n", " ");
   fprintf(stderr, "%-25s  8 - certUsageVerifyCA\n", " ");
   fprintf(stderr, "%-25s  9 - certUsageProtectedObjectSigner\n", " ");
   fprintf(stderr, "%-25s 10 - certUsageStatusResponder\n", " ");
   fprintf(stderr, "%-25s 11 - certUsageAnyCA\n", " ");
   fprintf(stderr, "%-25s 12 - certUsageIPsec\n", " ");

   exit(-1);
}

static int
HashDecodeAndVerify(FILE *out, FILE *content, PRFileDesc *signature,
                   SECCertUsage usage, char *progName)
{
   SECItem derdata;
   SEC_PKCS7ContentInfo *cinfo;
   SEC_PKCS7SignedData *signedData;
   HASH_HashType digestType;
   SECItem digest;
   unsigned char buffer[32];

   if (SECU_ReadDERFromFile(&derdata, signature, PR_FALSE,
                            PR_FALSE) != SECSuccess) {
       SECU_PrintError(progName, "error reading signature file");
       return -1;
   }

   cinfo = SEC_PKCS7DecodeItem(&derdata, NULL, NULL, NULL, NULL,
                               NULL, NULL, NULL);
   if (cinfo == NULL)
       return -1;

   if (!SEC_PKCS7ContentIsSigned(cinfo)) {
       fprintf(out, "Signature file is pkcs7 data, but not signed.\n");
       return -1;
   }

   signedData = cinfo->content.signedData;

   /* assume that there is only one digest algorithm for now */
   digestType = HASH_GetHashTypeByOidTag(
       SECOID_GetAlgorithmTag(signedData->digestAlgorithms[0]));
   if (digestType == HASH_AlgNULL) {
       fprintf(out, "Invalid hash algorithmID\n");
       return -1;
   }

   digest.data = buffer;
   if (DigestFile(digest.data, &digest.len, 32, content, digestType)) {
       SECU_PrintError(progName, "problem computing message digest");
       return -1;
   }

   fprintf(out, "Signature is ");
   if (SEC_PKCS7VerifyDetachedSignature(cinfo, usage, &digest, digestType,
                                        PR_FALSE))
       fprintf(out, "valid.\n");
   else
       fprintf(out, "invalid (Reason: %s).\n",
               SECU_Strerror(PORT_GetError()));

   SECITEM_FreeItem(&derdata, PR_FALSE);
   SEC_PKCS7DestroyContentInfo(cinfo);
   return 0;
}

int
main(int argc, char **argv)
{
   char *progName;
   FILE *contentFile, *outFile;
   PRFileDesc *signatureFile;
   SECCertUsage certUsage = certUsageEmailSigner;
   PLOptState *optstate;
   PLOptStatus status;
   SECStatus rv;

   progName = strrchr(argv[0], '/');
   progName = progName ? progName + 1 : argv[0];

   contentFile = NULL;
   signatureFile = NULL;
   outFile = NULL;

   /*
    * Parse command line arguments
    */
   optstate = PL_CreateOptState(argc, argv, "c:d:o:s:u:");
   while ((status = PL_GetNextOpt(optstate)) == PL_OPT_OK) {
       switch (optstate->option) {
           case '?':
               Usage(progName);
               break;

           case 'c':
               contentFile = fopen(optstate->value, "r");
               if (!contentFile) {
                   fprintf(stderr, "%s: unable to open \"%s\" for reading\n",
                           progName, optstate->value);
                   return -1;
               }
               break;

           case 'd':
               SECU_ConfigDirectory(optstate->value);
               break;

           case 'o':
               outFile = fopen(optstate->value, "w");
               if (!outFile) {
                   fprintf(stderr, "%s: unable to open \"%s\" for writing\n",
                           progName, optstate->value);
                   return -1;
               }
               break;

           case 's':
               signatureFile = PR_Open(optstate->value, PR_RDONLY, 0);
               if (!signatureFile) {
                   fprintf(stderr, "%s: unable to open \"%s\" for reading\n",
                           progName, optstate->value);
                   return -1;
               }
               break;

           case 'u': {
               int usageType;

               usageType = atoi(optstate->value);
               if (usageType < certUsageSSLClient || usageType > certUsageIPsec)
                   return -1;
               certUsage = (SECCertUsage)usageType;
               break;
           }
       }
   }
   PL_DestroyOptState(optstate);

   if (!contentFile)
       Usage(progName);
   if (!signatureFile)
       Usage(progName);
   if (!outFile)
       outFile = stdout;

   /* Call the NSS initialization routines */
   PR_Init(PR_SYSTEM_THREAD, PR_PRIORITY_NORMAL, 1);
   rv = NSS_Init(SECU_ConfigDirectory(NULL));
   if (rv != SECSuccess) {
       SECU_PrintPRandOSError(progName);
       return -1;
   }

   if (HashDecodeAndVerify(outFile, contentFile, signatureFile,
                           certUsage, progName)) {
       SECU_PrintError(progName, "problem decoding/verifying signature");
       return -1;
   }

   fclose(contentFile);
   PR_Close(signatureFile);
   if (outFile && outFile != stdout) {
       fclose(outFile);
   }

   if (NSS_Shutdown() != SECSuccess) {
       exit(1);
   }

   return 0;
}