Add the nss/lib/pkcs12 directory from NSS (Mozilla's Network Security Services) to third_party. Th…

nss_pkcs12/p12dec.c

+/* 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/. */
+
+#include "pkcs12.h"
+#include "plarena.h"
+#include "secpkcs7.h"
+#include "p12local.h"
+#include "secoid.h"
+#include "secitem.h"
+#include "secport.h"
+#include "secasn1.h"
+#include "secder.h"
+#include "secerr.h"
+#include "cert.h"
+#include "certdb.h"
+#include "p12plcy.h"
+#include "p12.h" 
+#include "secpkcs5.h" 
+
+/* PFX extraction and validation routines */
+
+/* decode the DER encoded PFX item.  if unable to decode, check to see if it
+ * is an older PFX item.  If that fails, assume the file was not a valid
+ * pfx file.
+ * the returned pfx structure should be destroyed using SEC_PKCS12DestroyPFX
+ */
+static SEC_PKCS12PFXItem *
+sec_pkcs12_decode_pfx(SECItem *der_pfx)
+{
+    SEC_PKCS12PFXItem *pfx;
+    SECStatus rv;
+
+    if(der_pfx == NULL) {
+        return NULL;
+    }
+
+    /* allocate the space for a new PFX item */
+    pfx = sec_pkcs12_new_pfx();
+    if(pfx == NULL) {
+        return NULL;
+    }
+
+    rv = SEC_ASN1DecodeItem(pfx->poolp, pfx, SEC_PKCS12PFXItemTemplate, 
+                            der_pfx);
+
+    /* if a failure occurred, check for older version...
+     * we also get rid of the old pfx structure, because we don't
+     * know where it failed and what data in may contain
+     */
+    if(rv != SECSuccess) {
+        SEC_PKCS12DestroyPFX(pfx);
+        pfx = sec_pkcs12_new_pfx();
+        if(pfx == NULL) {
+            return NULL;
+        }
+        rv = SEC_ASN1DecodeItem(pfx->poolp, pfx, SEC_PKCS12PFXItemTemplate_OLD, 
+                                der_pfx);
+        if(rv != SECSuccess) {
+            PORT_SetError(SEC_ERROR_PKCS12_DECODING_PFX);
+            PORT_FreeArena(pfx->poolp, PR_TRUE);
+            return NULL;
+        }
+        pfx->old = PR_TRUE;
+        SGN_CopyDigestInfo(pfx->poolp, &pfx->macData.safeMac, &pfx->old_safeMac);
+        SECITEM_CopyItem(pfx->poolp, &pfx->macData.macSalt, &pfx->old_macSalt);
+    } else {
+        pfx->old = PR_FALSE;
+    }
+
+    /* convert bit string from bits to bytes */
+    pfx->macData.macSalt.len /= 8;
+
+    return pfx;
+}
+
+/* validate the integrity MAC used in the PFX.  The MAC is generated
+ * per the PKCS 12 document.  If the MAC is incorrect, it is most likely
+ * due to an invalid password.
+ * pwitem is the integrity password
+ * pfx is the decoded pfx item
+ */
+static PRBool 
+sec_pkcs12_check_pfx_mac(SEC_PKCS12PFXItem *pfx,
+                         SECItem *pwitem)
+{
+    SECItem *key = NULL, *mac = NULL, *data = NULL;
+    SECItem *vpwd = NULL;
+    SECOidTag algorithm;
+    PRBool ret = PR_FALSE;
+
+    if(pfx == NULL) {
+        return PR_FALSE;
+    }
+
+    algorithm = SECOID_GetAlgorithmTag(&pfx->macData.safeMac.digestAlgorithm);
+    switch(algorithm) {
+        /* only SHA1 hashing supported as a MACing algorithm */
+        case SEC_OID_SHA1:
+            if(pfx->old == PR_FALSE) {
+                pfx->swapUnicode = PR_FALSE;
+            }
+
+recheckUnicodePassword:
+            vpwd = sec_pkcs12_create_virtual_password(pwitem, 
+                                                &pfx->macData.macSalt, 
+                                                pfx->swapUnicode);
+            if(vpwd == NULL) {
+                return PR_FALSE;
+            }
+
+            key = sec_pkcs12_generate_key_from_password(algorithm,
+                                                &pfx->macData.macSalt, 
+                                                (pfx->old ? pwitem : vpwd));
+            /* free vpwd only for newer PFX */
+            if(vpwd) {
+                SECITEM_ZfreeItem(vpwd, PR_TRUE);
+            }
+            if(key == NULL) {
+                return PR_FALSE;
+            }
+
+            data = SEC_PKCS7GetContent(&pfx->authSafe);
+            if(data == NULL) {
+                break;
+            }
+
+            /* check MAC */
+            mac = sec_pkcs12_generate_mac(key, data, pfx->old);
+            ret = PR_TRUE;
+            if(mac) {
+                SECItem *safeMac = &pfx->macData.safeMac.digest;
+                if(SECITEM_CompareItem(mac, safeMac) != SECEqual) {
+
+                    /* if we encounter an invalid mac, lets invert the
+                     * password in case of unicode changes 
+                     */
+                    if(((!pfx->old) && pfx->swapUnicode) || (pfx->old)){
+                        PORT_SetError(SEC_ERROR_PKCS12_INVALID_MAC);
+                        ret = PR_FALSE;
+                    } else {
+                        SECITEM_ZfreeItem(mac, PR_TRUE);
+                        pfx->swapUnicode = PR_TRUE;
+                        goto recheckUnicodePassword;
+                    }
+                } 
+                SECITEM_ZfreeItem(mac, PR_TRUE);
+            } else {
+                ret = PR_FALSE;
+            }
+            break;
+        default:
+            PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_MAC_ALGORITHM);
+            ret = PR_FALSE;
+            break;
+    }
+
+    /* let success fall through */
+    if(key != NULL)
+        SECITEM_ZfreeItem(key, PR_TRUE);
+
+    return ret;
+}
+
+/* check the validity of the pfx structure.  we currently only support
+ * password integrity mode, so we check the MAC.
+ */
+static PRBool 
+sec_pkcs12_validate_pfx(SEC_PKCS12PFXItem *pfx, 
+                        SECItem *pwitem)
+{
+    SECOidTag contentType;
+
+    contentType = SEC_PKCS7ContentType(&pfx->authSafe);
+    switch(contentType)
+    {
+        case SEC_OID_PKCS7_DATA:
+            return sec_pkcs12_check_pfx_mac(pfx, pwitem);
+            break;
+        case SEC_OID_PKCS7_SIGNED_DATA:
+        default:
+            PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_TRANSPORT_MODE);
+            break;
+    }
+
+    return PR_FALSE;
+}
+
+/* decode and return the valid PFX.  if the PFX item is not valid,
+ * NULL is returned.
+ */
+static SEC_PKCS12PFXItem *
+sec_pkcs12_get_pfx(SECItem *pfx_data, 
+                   SECItem *pwitem)
+{
+    SEC_PKCS12PFXItem *pfx;
+    PRBool valid_pfx;
+
+    if((pfx_data == NULL) || (pwitem == NULL)) {
+        return NULL;
+    }
+
+    pfx = sec_pkcs12_decode_pfx(pfx_data);
+    if(pfx == NULL) {
+        return NULL;
+    }
+
+    valid_pfx = sec_pkcs12_validate_pfx(pfx, pwitem);
+    if(valid_pfx != PR_TRUE) {
+        SEC_PKCS12DestroyPFX(pfx);
+        pfx = NULL;
+    }
+
+    return pfx;
+}
+
+/* authenticated safe decoding, validation, and access routines
+ */
+
+/* convert dogbert beta 3 authenticated safe structure to a post
+ * beta three structure, so that we don't have to change more routines.
+ */
+static SECStatus
+sec_pkcs12_convert_old_auth_safe(SEC_PKCS12AuthenticatedSafe *asafe)
+{
+    SEC_PKCS12Baggage *baggage;
+    SEC_PKCS12BaggageItem *bag;
+    SECStatus rv = SECSuccess;
+
+    if(asafe->old_baggage.espvks == NULL) {
+        /* XXX should the ASN1 engine produce a single NULL element list
+         * rather than setting the pointer to NULL?  
+         * There is no need to return an error -- assume that the list
+         * was empty.
+         */
+        return SECSuccess;
+    }
+
+    baggage = sec_pkcs12_create_baggage(asafe->poolp);
+    if(!baggage) {
+        return SECFailure;
+    }
+    bag = sec_pkcs12_create_external_bag(baggage);
+    if(!bag) {
+        return SECFailure;
+    }
+
+    PORT_Memcpy(&asafe->baggage, baggage, sizeof(SEC_PKCS12Baggage));
+
+    /* if there are shrouded keys, append them to the bag */
+    rv = SECSuccess;
+    if(asafe->old_baggage.espvks[0] != NULL) {
+        int nEspvk = 0;
+        rv = SECSuccess;
+        while((asafe->old_baggage.espvks[nEspvk] != NULL) && 
+                (rv == SECSuccess)) {
+            rv = sec_pkcs12_append_shrouded_key(bag, 
+                                        asafe->old_baggage.espvks[nEspvk]);
+            nEspvk++;
+        }
+    }
+
+    return rv;
+}    
+
+/* decodes the authenticated safe item.  a return of NULL indicates
+ * an error.  however, the error will have occurred either in memory
+ * allocation or in decoding the authenticated safe.
+ *
+ * if an old PFX item has been found, we want to convert the
+ * old authenticated safe to the new one.
+ */
+static SEC_PKCS12AuthenticatedSafe *
+sec_pkcs12_decode_authenticated_safe(SEC_PKCS12PFXItem *pfx) 
+{
+    SECItem *der_asafe = NULL;
+    SEC_PKCS12AuthenticatedSafe *asafe = NULL;
+    SECStatus rv;
+
+    if(pfx == NULL) {
+        return NULL;
+    }
+
+    der_asafe = SEC_PKCS7GetContent(&pfx->authSafe);
+    if(der_asafe == NULL) {
+        /* XXX set error ? */
+        goto loser;
+    }
+
+    asafe = sec_pkcs12_new_asafe(pfx->poolp);
+    if(asafe == NULL) {
+        goto loser;
+    }
+
+    if(pfx->old == PR_FALSE) {
+        rv = SEC_ASN1DecodeItem(pfx->poolp, asafe, 
+                                SEC_PKCS12AuthenticatedSafeTemplate, 
+                                der_asafe);
+        asafe->old = PR_FALSE;
+        asafe->swapUnicode = pfx->swapUnicode;
+    } else {
+        /* handle beta exported files */
+        rv = SEC_ASN1DecodeItem(pfx->poolp, asafe, 
+                                SEC_PKCS12AuthenticatedSafeTemplate_OLD,
+                                der_asafe);
+        asafe->safe = &(asafe->old_safe);
+        rv = sec_pkcs12_convert_old_auth_safe(asafe);
+        asafe->old = PR_TRUE;
+    }
+
+    if(rv != SECSuccess) {
+        goto loser;
+    }
+
+    asafe->poolp = pfx->poolp;
+    
+    return asafe;
+
+loser:
+    return NULL;
+}
+
+/* validates the safe within the authenticated safe item.  
+ * in order to be valid:
+ *  1.  the privacy salt must be present
+ *  2.  the encryption algorithm must be supported (including
+ *      export policy)
+ * PR_FALSE indicates an error, PR_TRUE indicates a valid safe
+ */
+static PRBool 
+sec_pkcs12_validate_encrypted_safe(SEC_PKCS12AuthenticatedSafe *asafe)
+{
+    PRBool valid = PR_FALSE;
+    SECAlgorithmID *algid;
+
+    if(asafe == NULL) {
+        return PR_FALSE;
+    }
+
+    /* if mode is password privacy, then privacySalt is assumed
+     * to be non-zero.
+     */
+    if(asafe->privacySalt.len != 0) {
+        valid = PR_TRUE;
+        asafe->privacySalt.len /= 8;
+    } else {
+        PORT_SetError(SEC_ERROR_PKCS12_CORRUPT_PFX_STRUCTURE);
+        return PR_FALSE;
+    }
+
+    /* until spec changes, content will have between 2 and 8 bytes depending
+     * upon the algorithm used if certs are unencrypted...
+     * also want to support case where content is empty -- which we produce 
+     */ 
+    if(SEC_PKCS7IsContentEmpty(asafe->safe, 8) == PR_TRUE) {
+        asafe->emptySafe = PR_TRUE;
+        return PR_TRUE;
+    }
+
+    asafe->emptySafe = PR_FALSE;
+
+    /* make sure that a pbe algorithm is being used */
+    algid = SEC_PKCS7GetEncryptionAlgorithm(asafe->safe);
+    if(algid != NULL) {
+        if(SEC_PKCS5IsAlgorithmPBEAlg(algid)) {
+            valid = SEC_PKCS12DecryptionAllowed(algid);
+
+            if(valid == PR_FALSE) {
+                PORT_SetError(SEC_ERROR_BAD_EXPORT_ALGORITHM);
+            }
+        } else {
+            PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_PBE_ALGORITHM);
+            valid = PR_FALSE;
+        }
+    } else {
+        valid = PR_FALSE;
+        PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_PBE_ALGORITHM);
+    }
+
+    return valid;
+}
+
+/* validates authenticates safe:
+ *  1.  checks that the version is supported
+ *  2.  checks that only password privacy mode is used (currently)
+ *  3.  further, makes sure safe has appropriate policies per above function
+ * PR_FALSE indicates failure.
+ */
+static PRBool 
+sec_pkcs12_validate_auth_safe(SEC_PKCS12AuthenticatedSafe *asafe)
+{
+    PRBool valid = PR_TRUE;
+    SECOidTag safe_type;
+    int version;
+
+    if(asafe == NULL) {
+        return PR_FALSE;
+    }
+
+    /* check version, since it is default it may not be present.
+     * therefore, assume ok
+     */
+    if((asafe->version.len > 0) && (asafe->old == PR_FALSE)) {
+        version = DER_GetInteger(&asafe->version);
+        if(version > SEC_PKCS12_PFX_VERSION) {
+            PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_VERSION);
+            return PR_FALSE;
+        }
+    }
+
+    /* validate password mode is being used */
+    safe_type = SEC_PKCS7ContentType(asafe->safe);
+    switch(safe_type)
+    {
+        case SEC_OID_PKCS7_ENCRYPTED_DATA:
+            valid = sec_pkcs12_validate_encrypted_safe(asafe);
+            break;
+        case SEC_OID_PKCS7_ENVELOPED_DATA:
+        default:
+            PORT_SetError(SEC_ERROR_PKCS12_UNSUPPORTED_TRANSPORT_MODE);
+            valid = PR_FALSE;
+            break;
+    }
+
+    return valid;
+}
+
+/* retrieves the authenticated safe item from the PFX item
+ *  before returning the authenticated safe, the validity of the
+ *  authenticated safe is checked and if valid, returned.
+ * a return of NULL indicates that an error occurred.
+ */
+static SEC_PKCS12AuthenticatedSafe *
+sec_pkcs12_get_auth_safe(SEC_PKCS12PFXItem *pfx)
+{
+    SEC_PKCS12AuthenticatedSafe *asafe;
+    PRBool valid_safe;
+
+    if(pfx == NULL) {
+        return NULL;
+    }
+
+    asafe = sec_pkcs12_decode_authenticated_safe(pfx);
+    if(asafe == NULL) {
+        return NULL;
+    }
+
+    valid_safe = sec_pkcs12_validate_auth_safe(asafe);
+    if(valid_safe != PR_TRUE) {
+        asafe = NULL;
+    } else if(asafe) {
+        asafe->baggage.poolp = asafe->poolp;
+    }
+
+    return asafe;
+}
+
+/* decrypts the authenticated safe.
+ * a return of anything but SECSuccess indicates an error.  the
+ * password is not known to be valid until the call to the 
+ * function sec_pkcs12_get_safe_contents.  If decoding the safe
+ * fails, it is assumed the password was incorrect and the error
+ * is set then.  any failure here is assumed to be due to 
+ * internal problems in SEC_PKCS7DecryptContents or below.
+ */
+static SECStatus
+sec_pkcs12_decrypt_auth_safe(SEC_PKCS12AuthenticatedSafe *asafe, 
+                             SECItem *pwitem,
+                             void *wincx)
+{
+    SECStatus rv = SECFailure;
+    SECItem *vpwd = NULL;
+
+    if((asafe == NULL) || (pwitem == NULL)) {
+        return SECFailure;
+    }
+
+    if(asafe->old == PR_FALSE) {
+        vpwd = sec_pkcs12_create_virtual_password(pwitem, &asafe->privacySalt,
+                                                 asafe->swapUnicode);
+        if(vpwd == NULL) {
+            return SECFailure;
+        }
+    }
+
+    rv = SEC_PKCS7DecryptContents(asafe->poolp, asafe->safe, 
+                                  (asafe->old ? pwitem : vpwd), wincx);
+
+    if(asafe->old == PR_FALSE) {
+        SECITEM_ZfreeItem(vpwd, PR_TRUE);
+    }
+
+    return rv;
+}
+
+/* extract the safe from the authenticated safe.
+ *  if we are unable to decode the safe, then it is likely that the 
+ *  safe has not been decrypted or the password used to decrypt
+ *  the safe was invalid.  we assume that the password was invalid and
+ *  set an error accordingly.
+ * a return of NULL indicates that an error occurred.
+ */
+static SEC_PKCS12SafeContents *
+sec_pkcs12_get_safe_contents(SEC_PKCS12AuthenticatedSafe *asafe)
+{
+    SECItem *src = NULL;
+    SEC_PKCS12SafeContents *safe = NULL;
+    SECStatus rv = SECFailure;
+
+    if(asafe == NULL) {
+        return NULL;
+    }
+
+    safe = (SEC_PKCS12SafeContents *)PORT_ArenaZAlloc(asafe->poolp, 
+                                                sizeof(SEC_PKCS12SafeContents));
+    if(safe == NULL) {
+        return NULL;
+    }
+    safe->poolp = asafe->poolp;
+    safe->old = asafe->old;
+    safe->swapUnicode = asafe->swapUnicode;
+
+    src = SEC_PKCS7GetContent(asafe->safe);
+    if(src != NULL) {
+        const SEC_ASN1Template *theTemplate;
+        if(asafe->old != PR_TRUE) {
+            theTemplate = SEC_PKCS12SafeContentsTemplate;
+        } else {
+            theTemplate = SEC_PKCS12SafeContentsTemplate_OLD;
+        }
+
+        rv = SEC_ASN1DecodeItem(asafe->poolp, safe, theTemplate, src);
+
+        /* if we could not decode the item, password was probably invalid */
+        if(rv != SECSuccess) {
+            safe = NULL;
+            PORT_SetError(SEC_ERROR_PKCS12_PRIVACY_PASSWORD_INCORRECT);
+        }
+    } else {
+        PORT_SetError(SEC_ERROR_PKCS12_CORRUPT_PFX_STRUCTURE);
+        rv = SECFailure;
+    }
+
+    return safe;
+}
+
+/* import PFX item 
+ * der_pfx is the der encoded pfx structure
+ * pbef and pbearg are the integrity/encryption password call back
+ * ncCall is the nickname collision calllback
+ * slot is the destination token
+ * wincx window handler
+ *
+ * on error, error code set and SECFailure returned 
+ */
+SECStatus
+SEC_PKCS12PutPFX(SECItem *der_pfx, SECItem *pwitem,
+                 SEC_PKCS12NicknameCollisionCallback ncCall,
+                 PK11SlotInfo *slot,
+                 void *wincx)
+{
+    SEC_PKCS12PFXItem *pfx;
+    SEC_PKCS12AuthenticatedSafe *asafe;
+    SEC_PKCS12SafeContents *safe_contents = NULL;
+    SECStatus rv;
+
+    if(!der_pfx || !pwitem || !slot) {
+        return SECFailure;
+    }
+
+    /* decode and validate each section */
+    rv = SECFailure;
+
+    pfx = sec_pkcs12_get_pfx(der_pfx, pwitem);
+    if(pfx != NULL) {
+        asafe = sec_pkcs12_get_auth_safe(pfx);
+        if(asafe != NULL) {
+
+            /* decrypt safe -- only if not empty */
+            if(asafe->emptySafe != PR_TRUE) {
+                rv = sec_pkcs12_decrypt_auth_safe(asafe, pwitem, wincx);
+                if(rv == SECSuccess) {
+                    safe_contents = sec_pkcs12_get_safe_contents(asafe);
+                    if(safe_contents == NULL) {
+                        rv = SECFailure;
+                    }
+                }
+            } else {
+                safe_contents = sec_pkcs12_create_safe_contents(asafe->poolp);
+                if(safe_contents == NULL) {
+                    rv = SECFailure;
+                } else {
+                    safe_contents->swapUnicode = pfx->swapUnicode;
+                    rv = SECSuccess;
+                }
+            }
+
+            /* get safe contents and begin import */
+            if(rv == SECSuccess) {
+                SEC_PKCS12DecoderContext *p12dcx;
+
+                p12dcx = sec_PKCS12ConvertOldSafeToNew(pfx->poolp, slot,
+                                        pfx->swapUnicode,
+                                        pwitem, wincx, safe_contents,
+                                        &asafe->baggage);
+                if(!p12dcx) {
+                    rv = SECFailure;
+                    goto loser;
+                }
+
+                if(SEC_PKCS12DecoderValidateBags(p12dcx, ncCall) 
+                                != SECSuccess) {
+                    rv = SECFailure;
+                    goto loser;
+                }
+
+                rv = SEC_PKCS12DecoderImportBags(p12dcx);
+            }
+
+        }
+    }
+
+loser:
+
+    if(pfx) {
+        SEC_PKCS12DestroyPFX(pfx);
+    }
+
+    return rv;
+}
+
+PRBool 
+SEC_PKCS12ValidData(char *buf, int bufLen, long int totalLength)
+{
+    int lengthLength;
+
+    PRBool valid = PR_FALSE;
+
+    if(buf == NULL) {
+        return PR_FALSE;
+    }
+
+    /* check for constructed sequence identifier tag */
+    if(*buf == (SEC_ASN1_CONSTRUCTED | SEC_ASN1_SEQUENCE)) {
+        totalLength--;   /* header byte taken care of */
+        buf++;
+
+        lengthLength = (long int)SEC_ASN1LengthLength(totalLength - 1);
+        if(totalLength > 0x7f) {
+            lengthLength--;
+            *buf &= 0x7f;  /* remove bit 8 indicator */
+            if((*buf - (char)lengthLength) == 0) {
+                valid = PR_TRUE;
+            }
+        } else {
+            lengthLength--;
+            if((*buf - (char)lengthLength) == 0) {
+                valid = PR_TRUE;
+            }
+        }
+    }
+
+    return valid;
+}