]> git.zerfleddert.de Git - proxmark3-svn/blobdiff - client/emv/emv_pki.c
fix rare bug in tlv.c (#788)
[proxmark3-svn] / client / emv / emv_pki.c
index 7803060e2e6b33eda5c471d182ed6d65f6708ce4..4e14483fe913a48ee9a04d4f4174e57635a0a637 100644 (file)
 #endif
 
 #include "emv_pki.h"
-#include "crypto.h"
-#include "dump.h"
-#include "util.h"
 
-#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdarg.h>
+#include "crypto.h"
+#include "dump.h"
+#include "util.h"
+#include "ui.h"
+
+static bool strictExecution = true;
+void PKISetStrictExecution(bool se) {
+       strictExecution = se;
+}
 
 static const unsigned char empty_tlv_value[] = {};
 static const struct tlv empty_tlv = {.tag = 0x0, .len = 0, .value = empty_tlv_value};
@@ -36,7 +41,8 @@ static unsigned char *emv_pki_decode_message(const struct emv_pk *enc_pk,
                uint8_t msgtype,
                size_t *len,
                const struct tlv *cert_tlv,
-               ... /* A list of tlv pointers, end with NULL */
+               int tlv_count,
+               ... /* A list of tlv pointers */
                )
 {
        struct crypto_pk *kcp;
@@ -48,12 +54,12 @@ static unsigned char *emv_pki_decode_message(const struct emv_pk *enc_pk,
                return NULL;
 
        if (!cert_tlv) {
-               printf("ERROR: Can't find certificate\n");
+               PrintAndLogEx(ERR, "Can't find certificate\n");
                return NULL;
        }
 
        if (cert_tlv->len != enc_pk->mlen) {
-               printf("ERROR: Certificate length (%d) not equal key length (%d)\n", cert_tlv->len, enc_pk->mlen);
+               PrintAndLogEx(ERR, "Certificate length (%zd) not equal key length (%zd)\n", cert_tlv->len, enc_pk->mlen);
                return NULL;
        }
        kcp = crypto_pk_open(enc_pk->pk_algo,
@@ -65,20 +71,20 @@ static unsigned char *emv_pki_decode_message(const struct emv_pk *enc_pk,
        data = crypto_pk_encrypt(kcp, cert_tlv->value, cert_tlv->len, &data_len);
        crypto_pk_close(kcp);
 
-/*     if (true){
-               printf("Recovered data:\n");
+       /*if (true){
+               PrintAndLogEx(INFO, "Recovered data:\n");
                dump_buffer(data, data_len, stdout, 0);
        }*/
-       
+
        if (data[data_len-1] != 0xbc || data[0] != 0x6a || data[1] != msgtype) {
-               printf("ERROR: Certificate format\n");
+               PrintAndLogEx(ERR, "Certificate format\n");
                free(data);
                return NULL;
        }
 
        size_t hash_pos = emv_pki_hash_psn[msgtype];
        if (hash_pos == 0 || hash_pos > data_len){
-               printf("ERROR: Cant get hash position in the certificate\n");
+               PrintAndLogEx(ERR, "Can't get hash position in the certificate\n");
                free(data);
                return NULL;
        }
@@ -86,7 +92,7 @@ static unsigned char *emv_pki_decode_message(const struct emv_pk *enc_pk,
        struct crypto_hash *ch;
        ch = crypto_hash_open(data[hash_pos]);
        if (!ch) {
-               printf("ERROR: Cant do hash\n");
+               PrintAndLogEx(ERR, "Can't do hash\n");
                free(data);
                return NULL;
        }
@@ -94,23 +100,29 @@ static unsigned char *emv_pki_decode_message(const struct emv_pk *enc_pk,
        size_t hash_len = crypto_hash_get_size(ch);
        crypto_hash_write(ch, data + 1, data_len - 2 - hash_len);
 
-       va_start(vl, cert_tlv);
-       while (true) {
+       va_start(vl, tlv_count);
+       for (int i = 0; i < tlv_count; i++) {
                const struct tlv *add_tlv = va_arg(vl, const struct tlv *);
                if (!add_tlv)
-                       break;
+                       continue;
 
                crypto_hash_write(ch, add_tlv->value, add_tlv->len);
        }
        va_end(vl);
 
-       if (memcmp(data + data_len - 1 - hash_len, crypto_hash_read(ch), hash_len)) {
-               printf("ERROR: Calculated wrong hash\n");
-               printf("decoded:    %s\n",sprint_hex(data + data_len - 1 - hash_len, hash_len));
-               printf("calculated: %s\n",sprint_hex(crypto_hash_read(ch), hash_len));
-               crypto_hash_close(ch);
-               free(data);
-               return NULL;
+       uint8_t hash[hash_len];
+       memset(hash, 0, hash_len);
+       memcpy(hash, crypto_hash_read(ch), hash_len);
+       if (memcmp(data + data_len - 1 - hash_len, hash, hash_len)) {
+               PrintAndLogEx(ERR, "Calculated wrong hash\n");
+               PrintAndLogEx(INFO, "decoded:    %s\n",sprint_hex(data + data_len - 1 - hash_len, hash_len));
+               PrintAndLogEx(INFO, "calculated: %s\n",sprint_hex(hash, hash_len));
+               
+               if (strictExecution) {
+                       crypto_hash_close(ch);
+                       free(data);
+                       return NULL;
+               }
        }
 
        crypto_hash_close(ch);
@@ -157,6 +169,7 @@ static struct emv_pk *emv_pki_decode_key_ex(const struct emv_pk *enc_pk,
                const struct tlv *exp_tlv,
                const struct tlv *rem_tlv,
                const struct tlv *add_tlv,
+               const struct tlv *sdatl_tlv,
                bool showData
                )
 {
@@ -176,23 +189,25 @@ static struct emv_pk *emv_pki_decode_key_ex(const struct emv_pk *enc_pk,
        else if (msgtype == 4)
                pan_length = 10;
        else {
-               printf("ERROR: Message type must be 2 or 4\n");
+               PrintAndLogEx(ERR, "Message type must be 2 or 4\n");
                return NULL;
        }
 
        data = emv_pki_decode_message(enc_pk, msgtype, &data_len,
                        cert_tlv,
+                       5,
                        rem_tlv,
                        exp_tlv,
                        add_tlv,
+                       sdatl_tlv,
                        NULL);
        if (!data || data_len < 11 + pan_length) {
-               printf("ERROR: Can't decode message\n");
+               PrintAndLogEx(ERR, "Can't decode message\n");
                return NULL;
        }
 
        if (showData){ 
-               printf("Recovered data:\n");
+               PrintAndLogEx(INFO, "Recovered data:\n");
                dump_buffer(data, data_len, stdout, 0);
        }
 
@@ -208,7 +223,7 @@ static struct emv_pk *emv_pki_decode_key_ex(const struct emv_pk *enc_pk,
 
        if (((msgtype == 2) && (pan2_len < 4 || pan2_len > pan_len)) ||
            ((msgtype == 4) && (pan2_len != pan_len))) {
-               printf("ERROR: Invalid PAN lengths\n");
+               PrintAndLogEx(ERR, "Invalid PAN lengths\n");
                free(data);
 
                return NULL;
@@ -217,9 +232,9 @@ static struct emv_pk *emv_pki_decode_key_ex(const struct emv_pk *enc_pk,
        unsigned i;
        for (i = 0; i < pan2_len; i++)
                if (emv_cn_get(pan_tlv, i) != emv_cn_get(&pan2_tlv, i)) {
-                       printf("ERROR: PAN data mismatch\n");
-                       printf("tlv  pan=%s\n", sprint_hex(pan_tlv->value, pan_tlv->len));
-                       printf("cert pan=%s\n", sprint_hex(pan2_tlv.value, pan2_tlv.len));
+                       PrintAndLogEx(ERR, "PAN data mismatch\n");
+                       PrintAndLogEx(INFO, "tlv  pan=%s\n", sprint_hex(pan_tlv->value, pan_tlv->len));
+                       PrintAndLogEx(INFO, "cert pan=%s\n", sprint_hex(pan2_tlv.value, pan2_tlv.len));
                        free(data);
 
                        return NULL;
@@ -227,7 +242,7 @@ static struct emv_pk *emv_pki_decode_key_ex(const struct emv_pk *enc_pk,
 
        pk_len = data[9 + pan_length];
        if (pk_len > data_len - 11 - pan_length + rem_tlv->len) {
-               printf("ERROR: Invalid pk length\n");
+               PrintAndLogEx(ERR, "Invalid pk length\n");
                free(data);
                return NULL;
        }
@@ -267,9 +282,10 @@ static struct emv_pk *emv_pki_decode_key(const struct emv_pk *enc_pk,
                const struct tlv *cert_tlv,
                const struct tlv *exp_tlv,
                const struct tlv *rem_tlv,
-               const struct tlv *add_tlv
+               const struct tlv *add_tlv,
+               const struct tlv *sdatl_tlv
                ) {
-       return emv_pki_decode_key_ex(enc_pk, msgtype, pan_tlv, cert_tlv, exp_tlv, rem_tlv, add_tlv, false);
+       return emv_pki_decode_key_ex(enc_pk, msgtype, pan_tlv, cert_tlv, exp_tlv, rem_tlv, add_tlv, sdatl_tlv, false);
 }
 
 struct emv_pk *emv_pki_recover_issuer_cert(const struct emv_pk *pk, struct tlvdb *db)
@@ -279,17 +295,30 @@ struct emv_pk *emv_pki_recover_issuer_cert(const struct emv_pk *pk, struct tlvdb
                        tlvdb_get(db, 0x90, NULL),
                        tlvdb_get(db, 0x9f32, NULL),
                        tlvdb_get(db, 0x92, NULL),
+                       NULL,
                        NULL);
 }
 
 struct emv_pk *emv_pki_recover_icc_cert(const struct emv_pk *pk, struct tlvdb *db, const struct tlv *sda_tlv)
 {
-       return emv_pki_decode_key(pk, 4,
+       size_t sdatl_len;
+       unsigned char *sdatl = emv_pki_sdatl_fill(db, &sdatl_len);
+       struct tlv sda_tdata = {
+               .tag = 0x00,        // dummy tag
+               .len = sdatl_len,
+               .value = sdatl
+       };
+       
+       struct emv_pk *res = emv_pki_decode_key(pk, 4,
                        tlvdb_get(db, 0x5a, NULL),
                        tlvdb_get(db, 0x9f46, NULL),
                        tlvdb_get(db, 0x9f47, NULL),
                        tlvdb_get(db, 0x9f48, NULL),
-                       sda_tlv);
+                       sda_tlv,
+                       &sda_tdata);
+                       
+       free(sdatl); // malloc here: emv_pki_sdatl_fill
+       return res;
 }
 
 struct emv_pk *emv_pki_recover_icc_pe_cert(const struct emv_pk *pk, struct tlvdb *db)
@@ -299,22 +328,67 @@ struct emv_pk *emv_pki_recover_icc_pe_cert(const struct emv_pk *pk, struct tlvdb
                        tlvdb_get(db, 0x9f2d, NULL),
                        tlvdb_get(db, 0x9f2e, NULL),
                        tlvdb_get(db, 0x9f2f, NULL),
+                       NULL,
                        NULL);
 }
 
+unsigned char *emv_pki_sdatl_fill(const struct tlvdb *db, size_t *sdatl_len) {
+       uint8_t buf[2048] = {0};
+       size_t len = 0;
+       
+       *sdatl_len = 0;
+       
+       const struct tlv *sda_tl = tlvdb_get(db, 0x9f4a, NULL);
+       if (!sda_tl || sda_tl->len <= 0)
+               return NULL;
+
+       for (int i = 0; i < sda_tl->len; i++) {
+               uint32_t tag = sda_tl->value[i]; // here may be multibyte, but now not
+               const struct tlv *elm = tlvdb_get(db, tag, NULL);
+               if (elm) {
+                       memcpy(&buf[len], elm->value, elm->len);
+                       len += elm->len;
+               }               
+       }
+       
+       if (len) {
+               *sdatl_len = len;
+               unsigned char *value = malloc(len);
+               memcpy(value, buf, len);
+               return value;
+       }
+       
+       return NULL;
+}
+
+
 struct tlvdb *emv_pki_recover_dac_ex(const struct emv_pk *enc_pk, const struct tlvdb *db, const struct tlv *sda_tlv, bool showData)
 {
        size_t data_len;
+       
+       // Static Data Authentication Tag List
+       size_t sdatl_len;
+       unsigned char *sdatl = emv_pki_sdatl_fill(db, &sdatl_len);
+       struct tlv sda_tdata = {
+               .tag = 0x00,        // dummy tag
+               .len = sdatl_len,
+               .value = sdatl
+       };
+
        unsigned char *data = emv_pki_decode_message(enc_pk, 3, &data_len,
                        tlvdb_get(db, 0x93, NULL),
+                       3,
                        sda_tlv,
+                       &sda_tdata,
                        NULL);
 
+       free(sdatl); // malloc here: emv_pki_sdatl_fill
+       
        if (!data || data_len < 5)
                return NULL;
 
        if (showData){
-               printf("Recovered data:\n");
+               PrintAndLogEx(INFO, "Recovered data:\n");
                dump_buffer(data, data_len, stdout, 0);
        }
 
@@ -324,6 +398,7 @@ struct tlvdb *emv_pki_recover_dac_ex(const struct emv_pk *enc_pk, const struct t
 
        return dac_db;
 }
+
 struct tlvdb *emv_pki_recover_dac(const struct emv_pk *enc_pk, const struct tlvdb *db, const struct tlv *sda_tlv) {
        return emv_pki_recover_dac_ex(enc_pk, db, sda_tlv, false);
 }
@@ -337,6 +412,7 @@ struct tlvdb *emv_pki_recover_idn_ex(const struct emv_pk *enc_pk, const struct t
        size_t data_len;
        unsigned char *data = emv_pki_decode_message(enc_pk, 5, &data_len,
                        tlvdb_get(db, 0x9f4b, NULL),
+                       2,
                        dyn_tlv,
                        NULL);
 
@@ -349,7 +425,7 @@ struct tlvdb *emv_pki_recover_idn_ex(const struct emv_pk *enc_pk, const struct t
        }
 
        if (showData){
-               printf("Recovered data:\n");
+               PrintAndLogEx(INFO, "Recovered data:\n");
                dump_buffer(data, data_len, stdout, 0);
        }
 
@@ -372,6 +448,7 @@ struct tlvdb *emv_pki_recover_atc_ex(const struct emv_pk *enc_pk, const struct t
        size_t data_len;
        unsigned char *data = emv_pki_decode_message(enc_pk, 5, &data_len,
                        tlvdb_get(db, 0x9f4b, NULL),
+                       5,
                        tlvdb_get(db, 0x9f37, NULL),
                        tlvdb_get(db, 0x9f02, NULL),
                        tlvdb_get(db, 0x5f2a, NULL),
@@ -387,7 +464,7 @@ struct tlvdb *emv_pki_recover_atc_ex(const struct emv_pk *enc_pk, const struct t
        }
 
        if (showData){
-               printf("Recovered data:\n");
+               PrintAndLogEx(INFO, "Recovered data:\n");
                dump_buffer(data, data_len, stdout, 0);
        }
 
@@ -448,26 +525,27 @@ struct tlvdb *emv_pki_perform_cda_ex(const struct emv_pk *enc_pk, const struct t
        size_t data_len = 0;
        unsigned char *data = emv_pki_decode_message(enc_pk, 5, &data_len,
                        tlvdb_get(this_db, 0x9f4b, NULL),
+                       2,
                        un_tlv,
                        NULL);
        if (!data || data_len < 3) {
-               printf("ERROR: can't decode message. len %d\n", data_len);
+               PrintAndLogEx(ERR, "can't decode message. len %zd\n", data_len);
                return NULL;
        }
 
        if (showData){
-               printf("Recovered data:\n");
+               PrintAndLogEx(INFO, "Recovered data:\n");
                dump_buffer(data, data_len, stdout, 0);
        }
 
        if (data[3] < 30 || data[3] > data_len - 4) {
-               printf("ERROR: Invalid data length\n");
+               PrintAndLogEx(ERR, "Invalid data length\n");
                free(data);
                return NULL;
        }
 
        if (!cid_tlv || cid_tlv->len != 1 || cid_tlv->value[0] != data[5 + data[4]]) {
-               printf("ERROR: CID mismatch\n");
+               PrintAndLogEx(ERR, "CID mismatch\n");
                free(data);
                return NULL;
        }
@@ -475,7 +553,7 @@ struct tlvdb *emv_pki_perform_cda_ex(const struct emv_pk *enc_pk, const struct t
        struct crypto_hash *ch;
        ch = crypto_hash_open(enc_pk->hash_algo);
        if (!ch) {
-               printf("ERROR: can't create hash\n");
+               PrintAndLogEx(ERR, "Can't create hash\n");
                free(data);
                return NULL;
        }
@@ -490,7 +568,7 @@ struct tlvdb *emv_pki_perform_cda_ex(const struct emv_pk *enc_pk, const struct t
        tlvdb_visit(this_db, tlv_hash, ch, 0);
 
        if (memcmp(data + 5 + data[4] + 1 + 8, crypto_hash_read(ch), 20)) {
-               printf("ERROR: calculated hash error\n");
+               PrintAndLogEx(ERR, "Calculated hash error\n");
                crypto_hash_close(ch);
                free(data);
                return NULL;
@@ -499,7 +577,7 @@ struct tlvdb *emv_pki_perform_cda_ex(const struct emv_pk *enc_pk, const struct t
 
        size_t idn_len = data[4];
        if (idn_len > data[3] - 1) {
-               printf("ERROR: Invalid IDN length\n");
+               PrintAndLogEx(ERR, "Invalid IDN length\n");
                free(data);
                return NULL;
        }
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