added random header to AES and removed malloc calls

.vscode/c_cpp_properties.json

@@ -5,7 +5,7 @@
             "defines": [],
             "includePath": [
                 "src",
-                "dependencies",
+                "dependencies/BearSSL/inc",
                 "dependencies/tlibc/include",
                 "${default}"
             ],

dependencies/bearssl.project.config

@@ -9,10 +9,7 @@ STD_CPP="c++11"
 WARN_C="-Wno-unknown-pragmas"
 # WARN_CPP="-Wall -Wextra"
 
-SRC_C=""
+SRC_C="$(find src -name '*.c')"
-for d in codec int hash rand rsa symcipher; do
-    SRC_C+=" $(find src/$d -name '*.c')"
-done
 #SRC_CPP="$(find src -name '*.cpp')"
 
 # Directory with dependency configs.
@@ -38,11 +35,13 @@ case "$OS" in
         EXEC_FILE="$PROJECT.exe"
         SHARED_LIB_FILE="$PROJECT.dll"
         LINKER_LIBS=""
+        DEFINE=""
         ;;
     LINUX)
         EXEC_FILE="$PROJECT"
         SHARED_LIB_FILE="$PROJECT.so"
         LINKER_LIBS=""
+        DEFINE="-DBR_USE_GETENTROPY=0"
         ;;
     *)
         error "operating system $OS has no configuration variants"
@@ -59,7 +58,7 @@ case "$TASK" in
         # -fprofile-use enables compiler to use profiling info files to optimize executable
         # -fprofile-prefix-path sets path where profiling info about objects are be saved
         # -fdata-sections -ffunction-sections -Wl,--gc-sections  removes unused code
-        C_ARGS="-O2 -flto=auto -fuse-linker-plugin -fprofile-use -fprofile-prefix-path=$(realpath $OBJDIR)/objects -fdata-sections -ffunction-sections -Wl,--gc-sections"
+        C_ARGS="$DEFINE -O2 -flto=auto -fuse-linker-plugin -fprofile-use -fprofile-prefix-path=$(realpath $OBJDIR)/objects -fdata-sections -ffunction-sections -Wl,--gc-sections"
         CPP_ARGS="$C_ARGS"
         LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
         PRE_TASK_SCRIPT=
@@ -68,7 +67,7 @@ case "$TASK" in
         ;;
     # creates executable with debug info and no optimizations
     build_exec_dbg)
-        C_ARGS="-O0 -g3"
+        C_ARGS="$DEFINE -O0 -g3"
         CPP_ARGS="$C_ARGS"
         LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
         PRE_TASK_SCRIPT=
@@ -77,7 +76,7 @@ case "$TASK" in
         ;;
     # creates shared library
     build_shared_lib)
-        C_ARGS="-O2 -fpic -flto -shared"
+        C_ARGS="$DEFINE -O2 -fpic -flto -shared"
         CPP_ARGS="$C_ARGS"
         LINKER_ARGS="$CPP_ARGS $LINKER_LIBS -Wl,-soname,$SHARED_LIB_FILE"
         PRE_TASK_SCRIPT=
@@ -86,7 +85,7 @@ case "$TASK" in
         ;;
     # creates shared library with debug symbols and no optimizations
     build_shared_lib_dbg)
-        C_ARGS="-O0 -g3 -fpic -shared"
+        C_ARGS="$DEFINE -O0 -g3 -fpic -shared"
         CPP_ARGS="$C_ARGS"
         LINKER_ARGS="$CPP_ARGS $LINKER_LIBS -Wl,-soname,$SHARED_LIB_FILE"
         PRE_TASK_SCRIPT=
@@ -95,7 +94,7 @@ case "$TASK" in
         ;;
     # creates static library
     build_static_lib)
-        C_ARGS="-O2 -fpic -fdata-sections -ffunction-sections"
+        C_ARGS="$DEFINE -O2 -fpic -fdata-sections -ffunction-sections"
         CPP_ARGS="$C_ARGS"
         PRE_TASK_SCRIPT=
         TASK_SCRIPT=cbuild/default_tasks/build_static_lib.sh
@@ -103,7 +102,7 @@ case "$TASK" in
         ;;
     # creates static library with debug symbols and no optimizations
     build_static_lib_dbg)
-        C_ARGS="-O0 -g3"
+        C_ARGS="$DEFINE -O0 -g3"
         CPP_ARGS="$C_ARGS"
         PRE_TASK_SCRIPT=
         TASK_SCRIPT=cbuild/default_tasks/build_static_lib.sh
@@ -127,7 +126,7 @@ case "$TASK" in
         # -pg adds code to executable, that generates file containing function call info (gmon.out)
         # -fprofile-generate generates executable with profiling code
         # -fprofile-prefix-path sets path where profiling info about objects will be saved
-        C_ARGS="-O2 -flto=auto -fuse-linker-plugin -fprofile-generate -fprofile-prefix-path=$(realpath $OBJDIR)/objects"
+        C_ARGS="$DEFINE -O2 -flto=auto -fuse-linker-plugin -fprofile-generate -fprofile-prefix-path=$(realpath $OBJDIR)/objects"
         CPP_ARGS="$C_ARGS"
         LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
         PRE_TASK_SCRIPT=cbuild/default_tasks/build_exec.sh
@@ -140,7 +139,7 @@ case "$TASK" in
     gprof)
         OUTDIR="$OUTDIR/gprof"
         # -pg adds code to executable, that generates file containing function call info (gmon.out)
-        C_ARGS="-O2 -flto=auto -fuse-linker-plugin -pg"
+        C_ARGS="$DEFINE -O2 -flto=auto -fuse-linker-plugin -pg"
         CPP_ARGS="$C_ARGS"
         LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
         PRE_TASK_SCRIPT=cbuild/default_tasks/build_exec.sh
@@ -154,7 +153,7 @@ case "$TASK" in
     callgrind)
         OUTDIR="$OUTDIR/callgrind"
         # -pg adds code to executable, that generates file containing function call info (gmon.out)
-        C_ARGS="-O2 -flto=auto -fuse-linker-plugin"
+        C_ARGS="$DEFINE -O2 -flto=auto -fuse-linker-plugin"
         CPP_ARGS="$C_ARGS"
         LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
         PRE_TASK_SCRIPT=cbuild/default_tasks/build_exec.sh
@@ -164,7 +163,7 @@ case "$TASK" in
     # compiles executable with sanitizers and executes it to find errors and warnings
     sanitize)
         OUTDIR="$OUTDIR/sanitize"
-        C_ARGS="-O0 -g3 -fsanitize=undefined,address"
+        C_ARGS="$DEFINE -O0 -g3 -fsanitize=undefined,address"
         CPP_ARGS="$C_ARGS"
         LINKER_ARGS="$CPP_ARGS $LINKER_LIBS"
         PRE_TASK_SCRIPT=cbuild/default_tasks/build_exec.sh

project.config

@@ -26,7 +26,7 @@ OBJDIR="obj"
 OUTDIR="bin"
 STATIC_LIB_FILE="lib$PROJECT.a"
 
-INCLUDE="-I./src -I./dependencies -I./dependencies/tlibc/include"
+INCLUDE="-I./src -I./dependencies/BearSSL/inc -I./dependencies/tlibc/include"
 
 # OS-specific options
 case "$OS" in

src/cryptography/AES.c

@@ -1,125 +1,95 @@
 #include "cryptography.h"
-#include "BearSSL/inc/bearssl_block.h"
 #include <assert.h>
+#include "tlibc/time.h"
 
-// size must be multiple of 16
+void EncryptorAES_create(EncryptorAES* ptr, Array key){
-#define __AES_BUFFER_SIZE 256
-
-typedef struct EncryptorAES {
-    br_aes_ct64_cbcenc_keys enc_ctx;
-    Array buf;
-    Array iv;
-} EncryptorAES;
-
-typedef struct DecryptorAES {
-    br_aes_ct64_cbcdec_keys dec_ctx;
-    Array buf;
-    Array iv;
-} DecryptorAES;
-
-EncryptorAES* EncryptorAES_create(Array key){
     assert(key.size == 16 || key.size == 24 || key.size == 32);
     
-    EncryptorAES* ptr = (EncryptorAES*)malloc(sizeof(EncryptorAES));
     br_aes_ct64_cbcenc_init(&ptr->enc_ctx, key.data, key.size);
 
-    // size must be multiple of 16
+    // uses CLOCK_REALTIME to seed rng
-    ptr->buf = Array_alloc(u8, __AES_BUFFER_SIZE);
+    nsec_t time_now = getTimeNsec();
-    Array_memset(&ptr->buf, 0);
+    br_hmac_drbg_init(&ptr->rng_ctx, &br_sha256_vtable, &time_now, sizeof(time_now));
 
-    // size of one SHA block (16 bytes)
+    memset(ptr->buf, 0, __AES_BUFFER_SIZE);
-    ptr->iv = Array_alloc(u8, 16); 
+    memset(ptr->iv, 0, sizeof(ptr->iv));
-    Array_memset(&ptr->iv, 0);
-
-    return ptr;
-}
-
-void EncryptorAES_destroy(EncryptorAES* ptr){
-    free(ptr->buf.data);
-    free(ptr->iv.data);
 }
 
 void EncryptorAES_encrypt(EncryptorAES* ptr, Array src, Array dst){
     assert(dst.size >= EncryptorAES_calcDstSize(src.size));
     
+    // write random bytes to the beginning of the buffer
+    br_hmac_drbg_generate(&ptr->rng_ctx, ptr->buf, __AES_RANDOM_BYTES_N);
     const EncryptedBlockInfo block_info = { .padding_size = 16 - src.size % 16 };
-    memcpy(ptr->buf.data, &block_info, sizeof(EncryptedBlockInfo));
+    // write struct after random_bytes
-    // encrypt this struct
+    memcpy((u8*)ptr->buf + __AES_RANDOM_BYTES_N, &block_info, sizeof(EncryptedBlockInfo));
-    br_aes_ct64_cbcenc_run(&ptr->enc_ctx, ptr->iv.data, ptr->buf.data, sizeof(EncryptedBlockInfo));
+    // encrypt buffer
-    // emit EncryptedBlockInfo to beginning of result
+    const u32 header_size = __AES_RANDOM_BYTES_N + sizeof(EncryptedBlockInfo);
-    memcpy(dst.data, ptr->buf.data, sizeof(EncryptedBlockInfo));
+    br_aes_ct64_cbcenc_run(&ptr->enc_ctx, ptr->iv, ptr->buf, header_size);
-    dst.data += sizeof(EncryptedBlockInfo);
+    // write encrypted header to dst
-    dst.size -= sizeof(EncryptedBlockInfo);
+    memcpy(dst.data, ptr->buf, header_size);
+    dst.data += header_size;
+    dst.size -= header_size;
 
     // write full blocks
-    while(src.size > ptr->buf.size){
+    while(src.size > __AES_BUFFER_SIZE){
-        memcpy(ptr->buf.data, src.data, ptr->buf.size);
+        memcpy(ptr->buf, src.data, __AES_BUFFER_SIZE);
-        src.data += ptr->buf.size;
+        src.data += __AES_BUFFER_SIZE;
-        src.size -= ptr->buf.size;
+        src.size -= __AES_BUFFER_SIZE;
-        br_aes_ct64_cbcenc_run(&ptr->enc_ctx, ptr->iv.data, ptr->buf.data, ptr->buf.size);
+        br_aes_ct64_cbcenc_run(&ptr->enc_ctx, ptr->iv, ptr->buf, __AES_BUFFER_SIZE);
-        memcpy(dst.data, ptr->buf.data, ptr->buf.size);
+        memcpy(dst.data, ptr->buf, __AES_BUFFER_SIZE);
-        dst.data += ptr->buf.size;
+        dst.data += __AES_BUFFER_SIZE;
-        dst.size -= ptr->buf.size;
+        dst.size -= __AES_BUFFER_SIZE;
     }
     
     // write incomplete block
-    Array_memset(&ptr->buf, 0);
+    memset(ptr->buf, 0, __AES_BUFFER_SIZE);
-    memcpy(ptr->buf.data, src.data, src.size);
+    memcpy(ptr->buf, src.data, src.size);
     u32 src_size_padded = src.size + block_info.padding_size;
-    br_aes_ct64_cbcenc_run(&ptr->enc_ctx, ptr->iv.data, ptr->buf.data, src_size_padded);
+    br_aes_ct64_cbcenc_run(&ptr->enc_ctx, ptr->iv, ptr->buf, src_size_padded);
-    memcpy(dst.data, ptr->buf.data, src_size_padded);
+    memcpy(dst.data, ptr->buf, src_size_padded);
 }
 
 
-DecryptorAES* DecryptorAES_create(Array key){
+void DecryptorAES_create(DecryptorAES* ptr, Array key){
     assert(key.size == 16 || key.size == 24 || key.size == 32);
     
-    DecryptorAES* ptr = (DecryptorAES*)malloc(sizeof(DecryptorAES));
     br_aes_ct64_cbcdec_init(&ptr->dec_ctx, key.data, key.size);
 
-    // size must be multiple of 16
+    memset(ptr->buf, 0, __AES_BUFFER_SIZE);
-    ptr->buf = Array_alloc(u8, __AES_BUFFER_SIZE);
+    memset(ptr->iv, 0, sizeof(ptr->iv));
-    Array_memset(&ptr->buf, 0);
-
-    // size of one SHA block (16 bytes)
-    ptr->iv = Array_alloc(u8, 16); 
-    Array_memset(&ptr->iv, 0);
-
-    return ptr;
-}
-
-void DecryptorAES_destroy(DecryptorAES* ptr){
-    free(ptr->buf.data);
-    free(ptr->iv.data);
 }
 
 void DecryptorAES_decrypt(DecryptorAES* ptr, Array src, Array dst, u32* decrypted_size){
     assert(dst.size >= src.size);
     
-    // read EncryptedBlockInfo from beginning of data
+    // copy encrypted header from src to buffer
+    const u32 header_size = __AES_RANDOM_BYTES_N + sizeof(EncryptedBlockInfo);
+    memcpy(ptr->buf, src.data, header_size);
+    src.data += header_size;
+    src.size -= header_size;
+    // decrypt buffer
+    br_aes_ct64_cbcdec_run(&ptr->dec_ctx, ptr->iv, &ptr->buf, header_size);
+    // read EncryptedBlockInfo from buffer
     EncryptedBlockInfo block_info;
-    memcpy(&block_info, src.data, sizeof(EncryptedBlockInfo));
+    memcpy(&block_info, (u8*)ptr->buf + __AES_RANDOM_BYTES_N, sizeof(EncryptedBlockInfo));
-    src.data += sizeof(EncryptedBlockInfo);
-    src.size -= sizeof(EncryptedBlockInfo);
-    // decrypt this struct
-    br_aes_ct64_cbcdec_run(&ptr->dec_ctx, ptr->iv.data, &block_info, sizeof(EncryptedBlockInfo));
     *decrypted_size = src.size - block_info.padding_size;
 
     // write full blocks
-    while(src.size > ptr->buf.size){
+    while(src.size > __AES_BUFFER_SIZE){
-        memcpy(ptr->buf.data, src.data, ptr->buf.size);
+        memcpy(ptr->buf, src.data, __AES_BUFFER_SIZE);
-        src.data += ptr->buf.size;
+        src.data += __AES_BUFFER_SIZE;
-        src.size -= ptr->buf.size;
+        src.size -= __AES_BUFFER_SIZE;
-        br_aes_ct64_cbcdec_run(&ptr->dec_ctx, ptr->iv.data, ptr->buf.data, ptr->buf.size);
+        br_aes_ct64_cbcdec_run(&ptr->dec_ctx, ptr->iv, ptr->buf, __AES_BUFFER_SIZE);
-        memcpy(dst.data, ptr->buf.data, ptr->buf.size);
+        memcpy(dst.data, ptr->buf, __AES_BUFFER_SIZE);
-        dst.data += ptr->buf.size;
+        dst.data += __AES_BUFFER_SIZE;
-        dst.size -= ptr->buf.size;
+        dst.size -= __AES_BUFFER_SIZE;
     }
     
     // write incomplete block
-    Array_memset(&ptr->buf, 0);
+    memset(ptr->buf, 0, __AES_BUFFER_SIZE);
-    memcpy(ptr->buf.data, src.data, src.size);
+    memcpy(ptr->buf, src.data, src.size);
     u32 src_size_padded = src.size + block_info.padding_size;
-    br_aes_ct64_cbcdec_run(&ptr->dec_ctx, ptr->iv.data, ptr->buf.data, src_size_padded);
+    br_aes_ct64_cbcdec_run(&ptr->dec_ctx, ptr->iv, ptr->buf, src_size_padded);
-    memcpy(dst.data, ptr->buf.data, src_size_padded);
+    memcpy(dst.data, ptr->buf, src_size_padded);
 }

src/cryptography/cryptography.h

@@ -2,40 +2,54 @@
 #include "tlibc/std.h"
 #include "tlibc/collections/Array.h"
 #include "tlibc/string/str.h"
+#include "bearssl_block.h"
+#include "bearssl_rand.h"
 
 /// @brief hashes password multiple times using its own hash as salt 
 /// @param password some byte array 
+/// @param out_buffer u8[hash_password_out_size]
 /// @param iterations number of iterations
-/// @return Array<u8, 32>
+void hash_password(str password, u8* out_buffer, i32 iterations);
-Array hash_password(str password, i32 iterations);
+#define hash_password_out_size 32
 
 
 typedef struct EncryptedBlockInfo {
-    u32 padding_size;
+    u8 padding_size;
     u32 _reserved;
     u64 __reserved;
-} EncryptedBlockInfo;
+} __attribute__((aligned(16))) EncryptedBlockInfo;
 
-typedef struct EncryptorAES EncryptorAES;
+// must be multiple of 16
+#define __AES_BUFFER_SIZE 512
+// must be multiple of 16
+#define __AES_RANDOM_BYTES_N 16
+
+typedef struct EncryptorAES {
+    br_aes_ct64_cbcenc_keys enc_ctx;
+    br_hmac_drbg_context rng_ctx;
+    u8 buf[__AES_BUFFER_SIZE];
+    u8 iv[16];
+} EncryptorAES;
 
 /// @param key Array<u8, 16 | 24 | 32>
-EncryptorAES* EncryptorAES_create(Array key);
+void EncryptorAES_create(EncryptorAES* ptr, Array key);
-
-void EncryptorAES_destroy(EncryptorAES* ptr);
 
 /// @brief Encrypts `src` and writes output to `dst`.
 /// @param src array of any size
 /// @param dst array of size >= EncryptorAES_calcDstSize(src.size)
 void EncryptorAES_encrypt(EncryptorAES* ptr, Array src, Array dst);
 
-#define EncryptorAES_calcDstSize(SRC_SIZE) (ALIGN_TO(SRC_SIZE, 16) + sizeof(EncryptedBlockInfo))
+#define EncryptorAES_calcDstSize(SRC_SIZE) (ALIGN_TO(SRC_SIZE, 16) + __AES_RANDOM_BYTES_N + sizeof(EncryptedBlockInfo))
 
-typedef struct DecryptorAES DecryptorAES;
+
+typedef struct DecryptorAES {
+    br_aes_ct64_cbcdec_keys dec_ctx;
+    u8 buf[__AES_BUFFER_SIZE];
+    u8 iv[16];
+} DecryptorAES;
 
 /// @param key Array<u8, 16 | 24 | 32>
-DecryptorAES* DecryptorAES_create(Array key);
+void DecryptorAES_create(DecryptorAES* ptr, Array key);
-
-void DecryptorAES_destroy(DecryptorAES* ptr);
 
 /// @brief Decrypts `src` and writes output to `dst`.
 /// @param src array of any size

src/cryptography/hash.c

@@ -1,18 +1,17 @@
 #include "cryptography.h"
-#include "BearSSL/inc/bearssl_hash.h"
+#include "bearssl_hash.h"
+#include "assert.h"
 
-Array hash_password(str password, i32 iterations){
+void hash_password(str password, u8* out_buffer, i32 iterations){
-    Array hash_buffer = Array_alloc(u8, br_sha256_SIZE);
+    assert(hash_password_out_size == br_sha256_SIZE);;
-    Array_memset(&hash_buffer, 0);
+    memset(out_buffer, 0, br_sha256_SIZE);
     br_sha256_context sha256_ctx;
     br_sha256_init(&sha256_ctx);
 
     for(i32 i = 0; i < iterations; i++){
         br_sha256_update(&sha256_ctx, password.data, password.size);
-        br_sha256_out(&sha256_ctx, hash_buffer.data);
+        br_sha256_out(&sha256_ctx, out_buffer);
-        br_sha256_update(&sha256_ctx, hash_buffer.data, hash_buffer.size);
+        br_sha256_update(&sha256_ctx, out_buffer, hash_password_out_size);
     }
-    br_sha256_out(&sha256_ctx, hash_buffer.data);
+    br_sha256_out(&sha256_ctx, out_buffer);
-
-    return hash_buffer;
 }

src/main.c

@@ -1,42 +1,44 @@
 #include "cryptography/cryptography.h"
 #include "network/network.h"
 #include "network/socket.h"
-#include <pthread.h>
 #include "tlibc/time.h"
-#include "errno.h"
+#include <pthread.h>
-#include <stdlib.h>
+#include <errno.h>
+#include <assert.h>
 
 Result(void) test_aes(){
     const str password = STR("abobus");
     const Array data = str_castTo_Array(STR("0123456789_hii_"));
     
-    const Array key_hash = hash_password(password, 1e5);
+    u8 hash_buffer[hash_password_out_size];
-    str hash_str = hex_to_str(key_hash, true);
-    printf("password hash [%i] %s\n", key_hash.size, hash_str.data);
-    free(hash_str.data);
-
     // SHA256  accepts keys with size 16, 24 or 32
     const u32 key_size = 32;
-    const Array key = Array_construct_size(key_hash.data, key_size);
+    assert(key_size <= hash_password_out_size);
+    const Array key = Array_construct_size(hash_buffer, key_size);
+    hash_password(password, hash_buffer, 1e5);
+    str hash_str = hex_to_str(key, true);
+    printf("key [%i] %s\n", key.size, hash_str.data);
+    free(hash_str.data);
 
-    EncryptorAES* encr = EncryptorAES_create(key);
+    EncryptorAES encr;
+    EncryptorAES_create(&encr, key);
     Array buffer = Array_alloc_size(EncryptorAES_calcDstSize(data.size));
-    EncryptorAES_encrypt(encr, data, buffer);
+    EncryptorAES_encrypt(&encr, data, buffer);
-    EncryptorAES_destroy(encr);
     
     str encrypted_str = hex_to_str(buffer, true);
     printf("data encrypted (hex):  %s\n", encrypted_str.data);
     free(encrypted_str.data);
 
-    DecryptorAES* decr = DecryptorAES_create(key);
+    DecryptorAES decr;
+    DecryptorAES_create(&decr, key);
     u32 decrypted_size = 0;
-    DecryptorAES_decrypt(decr, buffer, buffer, &decrypted_size);
+    DecryptorAES_decrypt(&decr, buffer, buffer, &decrypted_size);
-    DecryptorAES_destroy(decr);
     
     str decrypted_str = str_copy(str_construct(buffer.data, decrypted_size, false));
     printf("data decrypted (utf8): %s\n", decrypted_str.data);
     free(decrypted_str.data);
     
+    free(buffer.data);
     return RESULT_VOID;
 }
 
@@ -155,8 +157,8 @@ Result(void) test_network(){
 
 int main(){
     try_fatal(_10, network_init(), );
-    // try_fatal(_20, test_aes(), );
+    try_fatal(_20, test_aes(), );
-    try_fatal(_30, test_network(), );
+    // try_fatal(_30, test_network(), );
     try_fatal(_100, network_deinit(), );
     return 0;
 }