const char *signCMSBlob(
struct CMSBlob *cms,
const char *keyfilename)
{
bool sigKeyContext_initialized = false;
CRYPT_CONTEXT sigKeyContext;
CRYPT_KEYSET cryptKeyset;
bool hashContext_initialized = false;
CRYPT_CONTEXT hashContext;
int tbs_lth; /* to-be-signed length */
unsigned char *tbsp = NULL; /* to-be-signed pointer */
unsigned char *hash[40]; /* stores sha256 message digest */
int signatureLength; /* RSA signature length */
unsigned char *signature = NULL; /* RSA signature bytes */
const char *errmsg = NULL;
struct SignerInfo *signerInfop =
(struct SignerInfo *)member_casn(&cms->content.signedData.signerInfos.
self, 0);
struct BlobEncapsulatedContentInfo *encapContentInfop =
&cms->content.signedData.encapContentInfo;
if (vsize_casn(&signerInfop->signedAttrs.self) == 0)
{
if ((tbs_lth = vsize_casn(&encapContentInfop->eContent)) < 0)
{
errmsg = "sizing eContent";
return errmsg;
}
tbsp = (unsigned char *)calloc(1, tbs_lth);
if (!tbsp)
{
errmsg = "out of memory";
return errmsg;
}
tbs_lth = read_casn(&encapContentInfop->eContent, tbsp);
}
else
{
// get the size of signed attributes and allocate space for them
if ((tbs_lth = size_casn(&signerInfop->signedAttrs.self)) < 0)
{
errmsg = "sizing SignerInfo";
return errmsg;
}
tbsp = (unsigned char *)calloc(1, tbs_lth);
if (!tbsp)
{
errmsg = "out of memory";
return errmsg;
}
// DER-encode signedAttrs
tbs_lth = encode_casn(&signerInfop->signedAttrs.self, tbsp);
*tbsp = ASN_SET; /* replace ASN.1 identifier octet with ASN_SET
* (0x31) */
}
// compute SHA-256 of signedAttrs
if (cryptCreateContext(&hashContext, CRYPT_UNUSED, CRYPT_ALGO_SHA2) < 0 ||
!(hashContext_initialized = true))
errmsg = "creating hash context";
else if (cryptEncrypt(hashContext, tbsp, tbs_lth) < 0 ||
cryptEncrypt(hashContext, tbsp, 0) < 0)
errmsg = "hashing attrs";
else if (cryptGetAttributeString(hashContext, CRYPT_CTXINFO_HASHVALUE,
hash, &signatureLength) < 0)
errmsg = "getting attr hash";
// get the key and sign it
else if (cryptKeysetOpen(&cryptKeyset, CRYPT_UNUSED, CRYPT_KEYSET_FILE,
keyfilename, CRYPT_KEYOPT_READONLY) < 0)
errmsg = "opening key set";
else if (cryptCreateContext(&sigKeyContext, CRYPT_UNUSED,
CRYPT_ALGO_RSA) < 0 ||
!(sigKeyContext_initialized = true))
errmsg = "creating RSA context";
else if (cryptGetPrivateKey(cryptKeyset, &sigKeyContext, CRYPT_KEYID_NAME,
"label", "password") < 0)
errmsg = "getting key";
else if (cryptCreateSignature(NULL, 0, &signatureLength, sigKeyContext,
hashContext) < 0)
errmsg = "signing";
// compute signature
else if ((signature =
(unsigned char *)calloc(1, signatureLength + 20)) == 0)
errmsg = "out of memory";
// second parameter is signatureMaxLength, so we allow a little more
else if (cryptCreateSignature
(signature, signatureLength + 20, &signatureLength, sigKeyContext,
hashContext) < 0)
errmsg = "signing";
// verify that the signature is right
else if (cryptCheckSignature(signature, signatureLength, sigKeyContext,
hashContext) < 0)
errmsg = "verifying";
if (hashContext_initialized)
{
cryptDestroyContext(hashContext);
hashContext_initialized = false;
}
if (sigKeyContext_initialized)
{
cryptDestroyContext(sigKeyContext);
sigKeyContext_initialized = false;
}
if (!errmsg)
{
struct SignerInfo sigInfo;
SignerInfo(&sigInfo, (ushort) 0);
decode_casn(&sigInfo.self, signature);
// copy the signature into the object
copy_casn(&signerInfop->signature, &sigInfo.signature);
delete_casn(&sigInfo.self);
}
if (signature)
free(signature);
if (tbsp)
free(tbsp);
return errmsg;
}
const char *signCMS(
struct CMS *cms,
const char *keyfilename,
bool bad)
{
bool hashContext_initialized = false;
CRYPT_CONTEXT hashContext;
bool sigKeyContext_initialized = false;
CRYPT_CONTEXT sigKeyContext;
CRYPT_KEYSET cryptKeyset;
int signatureLength;
int tbs_lth;
char *msg = (char *)0;
uchar *tbsp;
uchar *signature = NULL;
uchar hash[40];
struct casn *sidp;
struct Attribute *attrp;
struct AttrTableDefined *attrtdp;
struct SignerInfo *sigInfop;
// signer info
// firat clear out any old stuff in signerInfos that may have been put
// there by old code
while (num_items(&cms->content.signedData.signerInfos.self) > 0)
eject_casn(&cms->content.signedData.signerInfos.self, 0);
sigInfop =
(struct SignerInfo *)
inject_casn(&(cms->content.signedData.signerInfos.self), 0);
// write the signature version (3) to the signer info
write_casn_num(&sigInfop->version.self, 3);
// find the SID
if ((sidp = findSID(cms)) == NULL)
return "finding SID";
// copy the CMS's SID over to the signature's SID
copy_casn(&sigInfop->sid.subjectKeyIdentifier, sidp);
// use sha256 as the algorithm
write_objid(&sigInfop->digestAlgorithm.algorithm, id_sha256);
// no parameters to sha256
write_casn(&sigInfop->digestAlgorithm.parameters.sha256, (uchar *) "", 0);
// first attribute: content type
attrp = (struct Attribute *)inject_casn(&sigInfop->signedAttrs.self, 0);
write_objid(&attrp->attrType, id_contentTypeAttr);
attrtdp =
(struct AttrTableDefined *)inject_casn(&attrp->attrValues.self, 0);
copy_casn(&attrtdp->contentType,
&cms->content.signedData.encapContentInfo.eContentType);
// second attribute: message digest
attrp = (struct Attribute *)inject_casn(&sigInfop->signedAttrs.self, 1);
write_objid(&attrp->attrType, id_messageDigestAttr);
// create the hash for the content
// first pull out the content
if ((tbs_lth =
readvsize_casn(&cms->content.signedData.encapContentInfo.eContent.
self, &tbsp)) < 0)
return "getting content";
// set up the context, initialize crypt
memset(hash, 0, 40);
if (cryptInit_wrapper() != CRYPT_OK)
return "initializing cryptlib";
// the following calls function f, and if f doesn't return 0 sets
// msg to m, then breaks out of the loop. Used immediately below.
#define CALL(f,m) if (f != 0) { msg = m; break; }
// use a "do { ... } while (0)" loop to bracket this code, so we can
// bail out on failure. (Note that this construct isn't really a
// loop; it's a way to use break as a more clean version of goto.)
do
{
// first sign the body of the message
// create the context
CALL(cryptCreateContext(&hashContext, CRYPT_UNUSED, CRYPT_ALGO_SHA2),
"creating context");
hashContext_initialized = true;
// generate the hash
CALL(cryptEncrypt(hashContext, tbsp, tbs_lth), "hashing");
CALL(cryptEncrypt(hashContext, tbsp, 0), "hashing");
// get the hash value. then we're done, so destroy it
CALL(cryptGetAttributeString
(hashContext, CRYPT_CTXINFO_HASHVALUE, hash, &signatureLength),
"getting first hash");
CALL(cryptDestroyContext(hashContext),
"destroying intermediate context");
// insert the hash as the first attribute
attrtdp =
(struct AttrTableDefined *)inject_casn(&attrp->attrValues.self, 0);
write_casn(&attrtdp->messageDigest, hash, signatureLength);
// create signing time attribute; mark the signing time as now
if (getenv("RPKI_NO_SIGNING_TIME") == NULL)
{
attrp =
(struct Attribute *)inject_casn(&sigInfop->signedAttrs.self, 2);
write_objid(&attrp->attrType, id_signingTimeAttr);
attrtdp =
(struct AttrTableDefined *)inject_casn(&attrp->attrValues.self, 0);
write_casn_time(&attrtdp->signingTime.utcTime, time((time_t *) 0));
}
// we are all done with the content
free(tbsp);
// now sign the attributes
// get the size of signed attributes and allocate space for them
if ((tbs_lth = size_casn(&sigInfop->signedAttrs.self)) < 0)
{
msg = "sizing SignerInfo";
break;
}
tbsp = (uchar *) calloc(1, tbs_lth);
encode_casn(&sigInfop->signedAttrs.self, tbsp);
*tbsp = ASN_SET;
// create a new, fresh hash context for hashing the attrs, and hash
// them
CALL(cryptCreateContext(&hashContext, CRYPT_UNUSED, CRYPT_ALGO_SHA2),
"creating hash context");
CALL(cryptEncrypt(hashContext, tbsp, tbs_lth), "hashing attrs");
CALL(cryptEncrypt(hashContext, tbsp, 0), "hashing attrs");
// get the hash value
CALL(cryptGetAttributeString
(hashContext, CRYPT_CTXINFO_HASHVALUE, hash, &signatureLength),
"getting attr hash");
// get the key and sign it
CALL(cryptKeysetOpen
(&cryptKeyset, CRYPT_UNUSED, CRYPT_KEYSET_FILE, keyfilename,
CRYPT_KEYOPT_READONLY), "opening key set");
CALL(cryptCreateContext(&sigKeyContext, CRYPT_UNUSED, CRYPT_ALGO_RSA),
"creating RSA context");
sigKeyContext_initialized = true;
CALL(cryptGetPrivateKey
(cryptKeyset, &sigKeyContext, CRYPT_KEYID_NAME, "label",
"password"), "getting key");
CALL(cryptCreateSignature
(NULL, 0, &signatureLength, sigKeyContext, hashContext),
"signing");
// check the signature to make sure it's right
signature = (uchar *) calloc(1, signatureLength + 20);
// second parameter is signatureMaxLength, so we allow a little more
CALL(cryptCreateSignature
(signature, signatureLength + 20, &signatureLength, sigKeyContext,
hashContext), "signing");
// verify that the signature is right
CALL(cryptCheckSignature
(signature, signatureLength, sigKeyContext, hashContext),
"verifying");
// end of protected block
} while (0);
// done with cryptlib, shut it down
if (hashContext_initialized)
{
cryptDestroyContext(hashContext);
hashContext_initialized = false;
}
if (sigKeyContext_initialized)
{
cryptDestroyContext(sigKeyContext);
sigKeyContext_initialized = false;
}
// did we have any trouble above? if so, bail
if (msg != 0)
{
return msg;
}
// ok, write the signature back to the object
struct SignerInfo sigInfo;
SignerInfo(&sigInfo, (ushort) 0);
decode_casn(&sigInfo.self, signature);
// were we supposed to make a bad signature? if so, make it bad
if (bad)
{
uchar *sig;
int siz = readvsize_casn(&sigInfo.signature, &sig);
sig[0]++;
write_casn(&sigInfo.signature, sig, siz);
free(sig);
}
// copy the signature into the object
copy_casn(&sigInfop->signature, &sigInfo.signature);
delete_casn(&sigInfo.self);
// all done with it now
free(signature);
// Mark it as encrypted with rsa, no params.
// See http://www.ietf.org/mail-archive/web/sidr/current/msg04813.html for
// why we use id_rsadsi_rsaEncryption instead of id_sha_256WithRSAEncryption
// here.
write_objid(&sigInfop->signatureAlgorithm.algorithm,
id_rsadsi_rsaEncryption);
write_casn(&sigInfop->signatureAlgorithm.parameters.self, (uchar *) "", 0);
// no errors, we return NULL
return NULL;
}
int funcion6()
{
int valido, tamFirma, tam, tamCert, i, status, keySize, keyMaxSize;
long opcion_l;
char opcion[5], *ptr, *endptr, *buffer, *rutaToCheck, *rutaFirma, *nombreFirma, *firma, *cert, *nombreCert, *rutaCert;
FILE *ptrFileToCheck, *ptrFirma, *ptrCert;
DIR *dir;
struct dirent *ent;
struct stat st;
/*Reservo memoria*/
rutaToCheck=(char *)malloc(120);
rutaFirma=(char *)malloc(120);
nombreFirma=(char *)malloc(50);
nombreCert=(char *)malloc(50);
rutaCert=(char *)malloc(120);
system("clear");
printf("\n ------------------------------------\n");
printf("| Verificar firma |\n");
printf(" ------------------------------------\n\n");
fflush(stdout);
/*PASO 1. Ruta del archivo a verificar*/
do {
valido=0;
printf("PASO 1. Introduzca la ruta del archivo que desea verificar: ");
scanf("%s", rutaToCheck);
if((ptrFileToCheck=fopen(rutaToCheck, "rb")) == NULL ) {
printf("No se encuentra el archivo. Revise la ruta :)\n\n");
valido=1;
fflush(stdout);
}
} while(valido==1);
/*Necesitamos abrir el archivo y volcarlo a memoria*/
stat(rutaToCheck, &st);
tam=st.st_size;
buffer=(char *)malloc(tam);
fread(buffer, 1, tam, ptrFileToCheck);
/*Buscamos el caracter '/' dentro de la cadena. Si está, es porque el usuario metió la ruta completa*/
if((ptr=(strrchr(rutaToCheck, '/')))!=NULL) sprintf(nombreFirma, "%s.p7s", ptr+1); //Ruta completa
else sprintf(nombreFirma, "%s.p7s", rutaToCheck); //El usuario metió el nombre del archivo
/*Ahora tengo que leer la firma. Primero la busco, y si no está, que la seleccione el usuario*/
dir = opendir ("./Firmas digitales/");
if (dir != NULL) {
i=0;
/* Vamos a buscar los archivos .p7s que correspondan*/
while ((ent = readdir (dir)) != NULL) {
if((ptr=strstr(ent->d_name, nombreFirma))!=NULL) {
i++;
}
}
closedir(dir);
} else {
/* Problemas al abrir el directorio */
printf("¿Ha ejecutado ya la opción 5?\n");
fflush(stdout);
return(-1);
}
if(i==0) { //Resultados = 0
printf("\nNo se ha encontrado una firma adecuada\n");
fflush(stdout);
printf("Seleccione cuál de los siguientes archivos corresponde con la firma creada en la función 5:\n ");
fflush(stdout);
dir = opendir ("./Firmas digitales/");
/* Nos va a mostrar los archivos .p15 que haya dentro de la carpeta Claves y cert.*/
while ((ent = readdir (dir)) != NULL) {
if((ptr=strstr(ent->d_name, ".p7s"))!=NULL) {
i++;
printf(" %d. %s\n", i, ent->d_name);
}
}
closedir(dir);
/*El usuario introduce el número que corresponde a la firma que elija*/
do{
valido=0;
printf("Introduzca el número de la firma que desea usar >> ");
scanf("%s", &opcion);
opcion_l = strtol(opcion,&endptr,10);
if(strlen(endptr)!=0 || opcion_l < 1 || opcion_l > i) {
printf("Ops... tendrás que meter un número entre 1 y %d la próxima vez ;) Try again!\n", i);
fflush(stdout);
valido=1;
}
}while(valido==1);
/*Guardamos el nombre del archivo correspondiente en rutaKeyset*/
dir = opendir ("./Firmas digitales/");
i=0;
while ((ent = readdir (dir)) != NULL) {
if((ptr=strstr(ent->d_name, ".p7s"))!=NULL) {
i++;
if(opcion_l==i) {
sprintf(rutaFirma, "./Firmas digitales/%s", ent->d_name);
}
}
}
closedir(dir);
} else if(i==1) {
printf("\n-> Se ha encontrado 1 firma adecuada. Se usará la firma %s por defecto\n\n", nombreFirma);
fflush(stdout);
sprintf(rutaFirma, "./Firmas digitales/%s", nombreFirma);
}
/*Abrimos la firma*/
if((ptrFirma=fopen(rutaFirma, "rb")) < 0) {
printf("Error al crear el archivo\n");
fflush(stdout);
return(-1);
}
stat(rutaFirma, &st);
tamFirma=st.st_size;
firma=(char *)malloc(tamFirma);
fread(firma, 1, tamFirma, ptrFirma);
/*Ahora necesitamos el certificado*/
dir = opendir ("./Claves y certificados/");
if (dir != NULL) {
i=0;
/* Nos va a mostrar los archivos que haya dentro de la carpeta Claves y cert.*/
while ((ent = readdir (dir)) != NULL) {
if((ptr=strstr(ent->d_name, ".cert"))!=NULL) {
strcpy(nombreCert, ent->d_name);
i++;
}
}
closedir(dir);
} else {
/* Problemas al abrir el directorio */
printf("¿Ha ejecutado ya la opción 1?\n");
fflush(stdout);
return(-1);
}
if(i==0) {
printf("No se ha encontrado ningún certificado. (¿Ha ejecutado ya la opción 1?)\n");
fflush(stdout);
return(-1);
} else if(i==1) {
printf("\n-> Se ha encontrado 1 certificado. Se usará el certificado %s por defecto\n\n", nombreCert);
fflush(stdout);
sprintf(rutaCert, "./Claves y certificados/%s", nombreCert);
} else {
printf("\n¡¡Hay %d certificados creados !!\n", i);
fflush(stdout);
i=0;
dir = opendir ("./Claves y certificados/");
/* Nos va a mostrar los archivos que haya dentro de la carpeta Claves y cert.*/
while ((ent = readdir (dir)) != NULL) {
if((ptr=strstr(ent->d_name, ".cert"))!=NULL) {
i++;
printf(" %d. %s\n", i, ent->d_name);
}
}
closedir(dir);
do{
valido=0;
printf("Introduzca el número del certificado que desea usar >> ");
scanf("%s", &opcion);
opcion_l = strtol(opcion,&endptr,10);
if(strlen(endptr)!=0 || opcion_l < 1 || opcion_l > i) {
printf("Ops... tendrás que meter un número entre 1 y %d la próxima vez ;) Try again!\n", i);
fflush(stdout);
valido=1;
}
}while(valido==1);
/*Guardamos el nombre del archivo correspondiente en rutaCert*/
dir = opendir ("./Claves y certificados/");
i=0;
while ((ent = readdir (dir)) != NULL) {
if((ptr=strstr(ent->d_name, ".cert"))!=NULL) {
i++;
if(opcion_l==i) {
sprintf(rutaCert, "./Claves y certificados/%s", ent->d_name);
}
}
}
closedir(dir);
}
ptrCert=fopen(rutaCert, "rb");
stat(rutaCert, &st);
tamCert=st.st_size;
cert=(char *)malloc(tamCert);
fread(cert, 1, tamCert, ptrCert);
/*Importamos certificado*/
/*Creo el contexto para el hash*/
CRYPT_CONTEXT contextoHash;
if((status=cryptCreateContext(&contextoHash, CRYPT_UNUSED, CRYPT_ALGO_SHA1))!=CRYPT_OK) {
printf("Error al crear el contexto. Código %d\n", status);
fflush(stdout);
return(-1);
}
/*Hash*/
if((status=cryptEncrypt(contextoHash, buffer, tam))!=CRYPT_OK) {
printf("Error al calcular el hash. Código %d\n", status);
fflush(stdout);
return(-1);
}
if((status=cryptEncrypt(contextoHash, buffer, 0))!=CRYPT_OK) {
printf("Error al calcular el hash. Código %d\n", status);
fflush(stdout);
return(-1);
}
CRYPT_CERTIFICATE certificado;
if((status=cryptImportCert(cert, tamCert, CRYPT_UNUSED, &certificado))!=CRYPT_OK) {
printf("Error al importar el certificado. Código %d\n", status);
fflush(stdout);
return(-1);
}
if((status=cryptCheckSignature(firma, tamFirma, certificado, contextoHash))!=CRYPT_OK) {
printf("La firma no concuerda. Código %d\n", status);
fflush(stdout);
return(-1);
}
/*Destruimos contextos y cerramos lo necesario*/
if((status=cryptDestroyContext(contextoHash))!=CRYPT_OK) {
printf("Error al destruir el contexto. Código %d\n", status);
fflush(stdout);
return(-1);
}
if((status=cryptDestroyCert(certificado))!=CRYPT_OK) {
printf("Error al destruir el certificado. Código %d\n", status);
fflush(stdout);
return(-1);
}
return(0);
}
