1 files changed, 658 insertions, 0 deletions
diff --git a/libs/libsignal/src/curve.c b/libs/libsignal/src/curve.c
new file mode 100644
index 0000000000..dcb27c17ea
--- /dev/null
+++ b/libs/libsignal/src/curve.c
@@ -0,0 +1,658 @@
+#include "curve.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <protobuf-c/protobuf-c.h>
+
+#include "curve25519/curve25519-donna.h"
+#include "curve25519/ed25519/additions/curve_sigs.h"
+#include "curve25519/ed25519/additions/generalized/gen_x.h"
+#include "curve25519/ed25519/tests/internal_fast_tests.h"
+#include "signal_protocol_internal.h"
+#include "signal_utarray.h"
+
+#define DJB_TYPE 0x05
+#define DJB_KEY_LEN 32
+#define VRF_VERIFY_LEN 32
+
+struct ec_public_key
+{
+    signal_type_base base;
+    uint8_t data[DJB_KEY_LEN];
+};
+
+struct ec_private_key
+{
+    signal_type_base base;
+    uint8_t data[DJB_KEY_LEN];
+};
+
+struct ec_key_pair
+{
+    signal_type_base base;
+    ec_public_key *public_key;
+    ec_private_key *private_key;
+};
+
+struct ec_public_key_list
+{
+    UT_array *values;
+};
+
+int curve_decode_point(ec_public_key **public_key, const uint8_t *key_data, size_t key_len, signal_context *global_context)
+{
+    ec_public_key *key = 0;
+
+    if(key_len > 0 && key_data[0] != DJB_TYPE) {
+        signal_log(global_context, SG_LOG_ERROR, "Invalid key type: %d", key_data[0]);
+        return SG_ERR_INVALID_KEY;
+    }
+
+    if(key_len != DJB_KEY_LEN + 1) {
+        signal_log(global_context, SG_LOG_ERROR, "Invalid key length: %d", key_len);
+        return SG_ERR_INVALID_KEY;
+    }
+
+    key = malloc(sizeof(ec_public_key));
+    if(!key) {
+        return SG_ERR_NOMEM;
+    }
+
+    SIGNAL_INIT(key, ec_public_key_destroy);
+
+    memcpy(key->data, key_data + 1, DJB_KEY_LEN);
+
+    *public_key = key;
+
+    return 0;
+}
+
+int ec_public_key_compare(const ec_public_key *key1, const ec_public_key *key2)
+{
+    if(key1 == key2) {
+        return 0;
+    }
+    else if(key1 == 0 && key2 != 0) {
+        return -1;
+    }
+    else if(key1 != 0 && key2 == 0) {
+        return 1;
+    }
+    else {
+        return signal_constant_memcmp(key1->data, key2->data, DJB_KEY_LEN);
+    }
+}
+
+int ec_public_key_memcmp(const ec_public_key *key1, const ec_public_key *key2)
+{
+    if(key1 == key2) {
+        return 0;
+    }
+    else if(key1 == 0 && key2 != 0) {
+        return -1;
+    }
+    else if(key1 != 0 && key2 == 0) {
+        return 1;
+    }
+    else {
+        return memcmp(key1->data, key2->data, DJB_KEY_LEN);
+    }
+}
+
+int ec_public_key_serialize(signal_buffer **buffer, const ec_public_key *key)
+{
+    signal_buffer *buf = 0;
+    uint8_t *data = 0;
+
+    if(!key) {
+        return SG_ERR_INVAL;
+    }
+
+    buf = signal_buffer_alloc(sizeof(uint8_t) * (DJB_KEY_LEN + 1));
+    if(!buf) {
+        return SG_ERR_NOMEM;
+    }
+
+    data = signal_buffer_data(buf);
+    data[0] = DJB_TYPE;
+    memcpy(data + 1, key->data, DJB_KEY_LEN);
+
+    *buffer = buf;
+
+    return 0;
+}
+
+int ec_public_key_serialize_protobuf(ProtobufCBinaryData *buffer, const ec_public_key *key)
+{
+    size_t len = 0;
+    uint8_t *data = 0;
+
+    assert(buffer);
+    assert(key);
+
+    len = sizeof(uint8_t) * (DJB_KEY_LEN + 1);
+    data = malloc(len);
+    if(!data) {
+        return SG_ERR_NOMEM;
+    }
+
+    data[0] = DJB_TYPE;
+    memcpy(data + 1, key->data, DJB_KEY_LEN);
+
+    buffer->data = data;
+    buffer->len = len;
+    return 0;
+}
+
+void ec_public_key_destroy(signal_type_base *type)
+{
+    ec_public_key *public_key = (ec_public_key *)type;
+    free(public_key);
+}
+
+int curve_decode_private_point(ec_private_key **private_key, const uint8_t *key_data, size_t key_len, signal_context *global_context)
+{
+    ec_private_key *key = 0;
+
+    if(key_len != DJB_KEY_LEN) {
+        signal_log(global_context, SG_LOG_ERROR, "Invalid key length: %d", key_len);
+        return SG_ERR_INVALID_KEY;
+    }
+
+    key = malloc(sizeof(ec_private_key));
+    if(!key) {
+        return SG_ERR_NOMEM;
+    }
+
+    SIGNAL_INIT(key, ec_private_key_destroy);
+
+    memcpy(key->data, key_data, DJB_KEY_LEN);
+
+    *private_key = key;
+
+    return 0;
+}
+
+int ec_private_key_compare(const ec_private_key *key1, const ec_private_key *key2)
+{
+    if(key1 == key2) {
+        return 0;
+    }
+    else if(key1 == 0 && key2 != 0) {
+        return -1;
+    }
+    else if(key1 != 0 && key2 == 0) {
+        return 1;
+    }
+    else {
+        return signal_constant_memcmp(key1->data, key2->data, DJB_KEY_LEN);
+    }
+}
+
+int ec_private_key_serialize(signal_buffer **buffer, const ec_private_key *key)
+{
+    signal_buffer *buf = 0;
+    uint8_t *data = 0 ;
+    
+    buf = signal_buffer_alloc(sizeof(uint8_t) * DJB_KEY_LEN);
+    if(!buf) {
+        return SG_ERR_NOMEM;
+    }
+
+    data = signal_buffer_data(buf);
+    memcpy(data, key->data, DJB_KEY_LEN);
+
+    *buffer = buf;
+
+    return 0;
+}
+
+int ec_private_key_serialize_protobuf(ProtobufCBinaryData *buffer, const ec_private_key *key)
+{
+    size_t len = 0;
+    uint8_t *data = 0;
+
+    assert(buffer);
+    assert(key);
+
+    len = sizeof(uint8_t) * DJB_KEY_LEN;
+    data = malloc(len);
+    if(!data) {
+        return SG_ERR_NOMEM;
+    }
+
+    memcpy(data, key->data, DJB_KEY_LEN);
+
+    buffer->data = data;
+    buffer->len = len;
+    return 0;
+}
+
+void ec_private_key_destroy(signal_type_base *type)
+{
+    ec_private_key *private_key = (ec_private_key *)type;
+    signal_explicit_bzero(private_key, sizeof(ec_private_key));
+    free(private_key);
+}
+
+int ec_key_pair_create(ec_key_pair **key_pair, ec_public_key *public_key, ec_private_key *private_key)
+{
+    ec_key_pair *result = malloc(sizeof(ec_key_pair));
+    if(!result) {
+        return SG_ERR_NOMEM;
+    }
+
+    SIGNAL_INIT(result, ec_key_pair_destroy);
+    result->public_key = public_key;
+    SIGNAL_REF(public_key);
+    result->private_key = private_key;
+    SIGNAL_REF(private_key);
+
+    *key_pair = result;
+
+    return 0;
+}
+
+ec_public_key *ec_key_pair_get_public(const ec_key_pair *key_pair)
+{
+    return key_pair->public_key;
+}
+
+ec_private_key *ec_key_pair_get_private(const ec_key_pair *key_pair)
+{
+    return key_pair->private_key;
+}
+
+void ec_key_pair_destroy(signal_type_base *type)
+{
+    ec_key_pair *key_pair = (ec_key_pair *)type;
+    SIGNAL_UNREF(key_pair->public_key);
+    SIGNAL_UNREF(key_pair->private_key);
+    free(key_pair);
+}
+
+int curve_generate_private_key(signal_context *context, ec_private_key **private_key)
+{
+    int result = 0;
+    ec_private_key *key = 0;
+
+    assert(context);
+
+    key = malloc(sizeof(ec_private_key));
+    if(!key) {
+        result = SG_ERR_NOMEM;
+        goto complete;
+    }
+
+    SIGNAL_INIT(key, ec_private_key_destroy);
+
+    result = signal_crypto_random(context, key->data, DJB_KEY_LEN);
+    if(result < 0) {
+        goto complete;
+    }
+
+    key->data[0] &= 248;
+    key->data[31] &= 127;
+    key->data[31] |= 64;
+
+complete:
+    if(result < 0) {
+        if(key) {
+            SIGNAL_UNREF(key);
+        }
+    }
+    else {
+        *private_key = key;
+    }
+
+    return result;
+}
+
+int curve_generate_public_key(ec_public_key **public_key, const ec_private_key *private_key)
+{
+    static const uint8_t basepoint[32] = {9};
+    int result = 0;
+
+    ec_public_key *key = malloc(sizeof(ec_public_key));
+    if(!key) {
+        return SG_ERR_NOMEM;
+    }
+
+    SIGNAL_INIT(key, ec_public_key_destroy);
+
+    result = curve25519_donna(key->data, private_key->data, basepoint);
+
+    if(result == 0) {
+        *public_key = key;
+        return 0;
+    }
+    else {
+        if(key) {
+            SIGNAL_UNREF(key);
+        }
+        return SG_ERR_UNKNOWN;
+    }
+}
+
+int curve_generate_key_pair(signal_context *context, ec_key_pair **key_pair)
+{
+    int result = 0;
+    ec_key_pair *pair_result = 0;
+    ec_private_key *key_private = 0;
+    ec_public_key *key_public = 0;
+
+    assert(context);
+
+    result = curve_generate_private_key(context, &key_private);
+    if(result < 0) {
+        goto complete;
+    }
+
+    result = curve_generate_public_key(&key_public, key_private);
+    if(result < 0) {
+        goto complete;
+    }
+
+    result = ec_key_pair_create(&pair_result, key_public, key_private);
+    if(result < 0) {
+        goto complete;
+    }
+
+complete:
+    if(key_public) {
+        SIGNAL_UNREF(key_public);
+    }
+    if(key_private) {
+        SIGNAL_UNREF(key_private);
+    }
+
+    if(result < 0) {
+        if(pair_result) {
+            SIGNAL_UNREF(pair_result);
+        }
+    }
+    else {
+        *key_pair = pair_result;
+    }
+
+    return result;
+}
+
+ec_public_key_list *ec_public_key_list_alloc()
+{
+    int result = 0;
+    ec_public_key_list *list = malloc(sizeof(ec_public_key_list));
+    if(!list) {
+        result = SG_ERR_NOMEM;
+        goto complete;
+    }
+
+    memset(list, 0, sizeof(ec_public_key_list));
+
+    utarray_new(list->values, &ut_ptr_icd);
+
+complete:
+    if(result < 0) {
+        if(list) {
+            free(list);
+        }
+        return 0;
+    }
+    else {
+        return list;
+    }
+}
+
+ec_public_key_list *ec_public_key_list_copy(const ec_public_key_list *list)
+{
+    int result = 0;
+    ec_public_key_list *result_list = 0;
+    unsigned int size;
+    unsigned int i;
+    ec_public_key **p;
+
+    result_list = ec_public_key_list_alloc();
+    if(!result_list) {
+        result = SG_ERR_NOMEM;
+        goto complete;
+    }
+
+    size = utarray_len(list->values);
+
+    utarray_reserve(result_list->values, size);
+
+    for (i = 0; i < size; i++) {
+        p = (ec_public_key **)utarray_eltptr(list->values, i);
+        result = ec_public_key_list_push_back(result_list, *p);
+        if(result < 0) {
+            goto complete;
+        }
+    }
+
+complete:
+    if(result < 0) {
+        if(result_list) {
+            ec_public_key_list_free(result_list);
+        }
+        return 0;
+    }
+    else {
+        return result_list;
+    }
+}
+
+int ec_public_key_list_push_back(ec_public_key_list *list, ec_public_key *value)
+{
+    int result = 0;
+    assert(list);
+    assert(value);
+
+    utarray_push_back(list->values, &value);
+    SIGNAL_REF(value);
+
+complete:
+    return result;
+}
+
+unsigned int ec_public_key_list_size(const ec_public_key_list *list)
+{
+    assert(list);
+    return utarray_len(list->values);
+}
+
+ec_public_key *ec_public_key_list_at(const ec_public_key_list *list, unsigned int index)
+{
+    ec_public_key **value = 0;
+
+    assert(list);
+    assert(index < utarray_len(list->values));
+
+    value = (ec_public_key **)utarray_eltptr(list->values, index);
+
+    assert(*value);
+
+    return *value;
+}
+
+int ec_public_key_list_sort_comparator(const void *a, const void *b)
+{
+    const ec_public_key *key1 = *((const ec_public_key **)a);
+    const ec_public_key *key2 = *((const ec_public_key **)b);
+    return ec_public_key_memcmp(key1, key2);
+}
+
+void ec_public_key_list_sort(ec_public_key_list *list)
+{
+    assert(list);
+    utarray_sort(list->values, ec_public_key_list_sort_comparator);
+}
+
+void ec_public_key_list_free(ec_public_key_list *list)
+{
+    unsigned int size;
+    unsigned int i;
+    ec_public_key **p;
+    if(list) {
+        size = utarray_len(list->values);
+        for (i = 0; i < size; i++) {
+            p = (ec_public_key **)utarray_eltptr(list->values, i);
+            SIGNAL_UNREF(*p);
+        }
+        utarray_free(list->values);
+        free(list);
+    }
+}
+
+int curve_calculate_agreement(uint8_t **shared_key_data, const ec_public_key *public_key, const ec_private_key *private_key)
+{
+    uint8_t *key = 0;
+    int result = 0;
+
+    if(!public_key || !private_key) {
+        return SG_ERR_INVALID_KEY;
+    }
+
+    key = malloc(DJB_KEY_LEN);
+    if(!key) {
+        return SG_ERR_NOMEM;
+    }
+
+    result = curve25519_donna(key, private_key->data, public_key->data);
+
+    if(result == 0) {
+        *shared_key_data = key;
+        return DJB_KEY_LEN;
+    }
+    else {
+        if(key) {
+            free(key);
+        }
+        return SG_ERR_UNKNOWN;
+    }
+}
+
+int curve_verify_signature(const ec_public_key *signing_key,
+        const uint8_t *message_data, size_t message_len,
+        const uint8_t *signature_data, size_t signature_len)
+{
+    if(signature_len != CURVE_SIGNATURE_LEN) {
+        return SG_ERR_INVAL;
+    }
+
+    return curve25519_verify(signature_data, signing_key->data, message_data, message_len) == 0;
+}
+
+int curve_calculate_signature(signal_context *context,
+        signal_buffer **signature,
+        const ec_private_key *signing_key,
+        const uint8_t *message_data, size_t message_len)
+{
+    int result = 0;
+    uint8_t random_data[CURVE_SIGNATURE_LEN];
+    signal_buffer *buffer = 0;
+
+    result = signal_crypto_random(context, random_data, sizeof(random_data));
+    if(result < 0) {
+        goto complete;
+    }
+
+    buffer = signal_buffer_alloc(CURVE_SIGNATURE_LEN);
+    if(!buffer) {
+        result = SG_ERR_NOMEM;
+        goto complete;
+    }
+
+    result = curve25519_sign(signal_buffer_data(buffer), signing_key->data, message_data, message_len, random_data);
+
+complete:
+    if(result < 0) {
+        if(buffer) {
+            signal_buffer_free(buffer);
+        }
+    }
+    else {
+        *signature = buffer;
+    }
+    return result;
+}
+
+int curve_verify_vrf_signature(signal_context *context,
+        signal_buffer **vrf_output,
+        const ec_public_key *signing_key,
+        const uint8_t *message_data, size_t message_len,
+        const uint8_t *signature_data, size_t signature_len)
+{
+    int result = 0;
+    signal_buffer *buffer = 0;
+
+    if(!signing_key) {
+        return SG_ERR_INVAL;
+    }
+
+    if(!message_data || !signature_data || signature_len != VRF_SIGNATURE_LEN) {
+        signal_log(context, SG_LOG_ERROR, "Invalid message or signature format");
+        return SG_ERR_VRF_SIG_VERIF_FAILED;
+    }
+
+    buffer = signal_buffer_alloc(VRF_VERIFY_LEN);
+    if(!buffer) {
+        result = SG_ERR_NOMEM;
+        goto complete;
+    }
+
+    result = generalized_xveddsa_25519_verify(signal_buffer_data(buffer),
+            signature_data, signing_key->data,
+            message_data, message_len, NULL, 0);
+    if(result != 0) {
+        signal_log(context, SG_LOG_ERROR, "Invalid signature");
+        result = SG_ERR_VRF_SIG_VERIF_FAILED;
+    }
+
+complete:
+    if(result < 0) {
+        signal_buffer_free(buffer);
+    }
+    else {
+        *vrf_output = buffer;
+    }
+    return result;
+}
+
+int curve_calculate_vrf_signature(signal_context *context,
+        signal_buffer **signature,
+        const ec_private_key *signing_key,
+        const uint8_t *message_data, size_t message_len)
+{
+    int result = 0;
+    uint8_t random_data[64];
+    signal_buffer *buffer = 0;
+
+    result = signal_crypto_random(context, random_data, sizeof(random_data));
+    if(result < 0) {
+        goto complete;
+    }
+
+    buffer = signal_buffer_alloc(VRF_SIGNATURE_LEN);
+    if(!buffer) {
+        result = SG_ERR_NOMEM;
+        goto complete;
+    }
+
+    result = generalized_xveddsa_25519_sign(signal_buffer_data(buffer),
+            signing_key->data,
+            message_data, message_len, random_data, NULL, 0);
+    if(result != 0) {
+        signal_log(context, SG_LOG_ERROR, "Signature failed!");
+        result = SG_ERR_UNKNOWN;
+    }
+
+complete:
+    if(result < 0) {
+        signal_buffer_free(buffer);
+    }
+    else {
+        *signature = buffer;
+    }
+    return result;
+}