Add v2.local CLI example tools

CMakeLists.txt

@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.10)
 project(libpaseto
-		VERSION 0.99
-		LANGUAGES C)
+	VERSION 0.99
+	LANGUAGES C)
 
 set(CMAKE_C_STANDARD 11)
 set(CMAKE_C_EXTENSIONS OFF)
@@ -13,40 +13,43 @@ include_directories(${SODIUM_INCLUDE_DIRS})
 
 include_directories(include)
 set(PASETO_SOURCES
-        src/paseto_v2_local.c
-        src/paseto_v2_public.c
-        src/paseto.c
-        src/helpers.c
-        src/helpers.h
-        include/paseto.h)
+	src/paseto_v2_local.c
+	src/paseto_v2_public.c
+	src/paseto.c
+	src/helpers.c
+	src/helpers.h
+	include/paseto.h)
 
-CONFIGURE_FILE("paseto.pc.in" "paseto.pc" @ONLY)
+configure_file("paseto.pc.in" "paseto.pc" @ONLY)
 
 
 # shared library build
 add_library(paseto SHARED ${PASETO_SOURCES})
 target_link_libraries(paseto ${SODIUM_LIBRARIES})
 install(TARGETS paseto
-        LIBRARY DESTINATION lib
-        ARCHIVE DESTINATION lib)
+	LIBRARY DESTINATION lib
+	ARCHIVE DESTINATION lib)
 install(FILES include/paseto.h
-        DESTINATION include)
+	DESTINATION include)
 install(FILES "${CMAKE_CURRENT_BINARY_DIR}/paseto.pc"
-        DESTINATION lib/pkgconfig)
+	DESTINATION lib/pkgconfig)
 
 # test executable
 add_executable(pasetotest
-        test/main.c
-        test/helpers.h
-        test/helpers.c
-        test/test.h
-        test/test.c
-        test/v2vectors.h
-        test/v2vectors.c
-        test/v2publicvectors.c)
+	test/main.c
+	test/helpers.h
+	test/helpers.c
+	test/test.h
+	test/test.c
+	test/v2vectors.h
+	test/v2vectors.c
+	test/v2publicvectors.c)
 target_compile_definitions(pasetotest PRIVATE _POSIX_C_SOURCE=200809L)
 target_link_libraries(pasetotest ${SODIUM_LIBRARIES} paseto)
 
-# example executable
-add_executable(example example.c)
-target_link_libraries(example ${SODIUM_LIBRARIES} paseto)
+# examples
+set(EXAMPLES example paseto-v2-local-encrypt paseto-v2-local-decrypt)
+foreach(EXAMPLE ${EXAMPLES})
+	add_executable(${EXAMPLE} examples/${EXAMPLE}.c)
+	target_link_libraries(${EXAMPLE} ${SODIUM_LIBRARIES} paseto)
+endforeach()

examples/paseto-v2-local-decrypt.c

@@ -0,0 +1,42 @@
+#include "paseto.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+// Loads v2.local-encrypted data from stdin, decrypts it using the hex-encoded
+// key in the PASETO_V2_LOCAL_SECRET environment variable and writes decrypted
+// data to stdout. The footer is not written to stdout.
+
+
+static const size_t BUF_SIZE = 64*1024;
+
+
+int main() {
+    if (!paseto_init()) {
+        fprintf(stderr, "Failed to initialize libpaseto\n");
+        exit(-1);
+    }
+
+    uint8_t key[paseto_v2_LOCAL_KEYBYTES];
+	if (!paseto_v2_local_load_key_base64(key,
+				getenv("PASETO_V2_LOCAL_SECRET"))) {
+        perror("Failed to load key");
+        exit(-1);
+    }
+    char *encrypted = malloc(BUF_SIZE);
+    if (!encrypted) {
+        perror("Failed to allocate input buffer");
+        exit(-1);
+    }
+    size_t encrypted_len = fread(encrypted, 1, BUF_SIZE - 1, stdin);
+	encrypted[encrypted_len] = '\0';
+	size_t message_len;
+    uint8_t *message = paseto_v2_local_decrypt(
+            encrypted, &message_len, key, NULL, NULL);
+	free(encrypted);
+    if (!message) {
+        perror("paseto_v2_local_decrypt failed");
+        exit(-1);
+    }
+	fwrite(message, 1, message_len, stdout);
+    paseto_free(message);
+}

examples/paseto-v2-local-encrypt.c

@@ -0,0 +1,40 @@
+#include "paseto.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+// Loads data from stdin, encrypts it using the hex-encoded key in the
+// PASETO_V2_LOCAL_SECRET environment variable and writes encrypted data to
+// stdout. A footer can not be specified.
+
+
+static const size_t BUF_SIZE = 64*1024;
+
+
+int main() {
+    if (!paseto_init()) {
+        fprintf(stderr, "Failed to initialize libpaseto\n");
+        exit(-1);
+    }
+
+    uint8_t key[paseto_v2_LOCAL_KEYBYTES];
+	if (!paseto_v2_local_load_key_base64(key,
+				getenv("PASETO_V2_LOCAL_SECRET"))) {
+        perror("Failed to load key");
+        exit(-1);
+    }
+    uint8_t *message = malloc(BUF_SIZE);
+    if (!message) {
+        perror("Failed to allocate input buffer");
+        exit(-1);
+    }
+    size_t message_len = fread(message, 1, BUF_SIZE - 1, stdin);
+    char *encrypted = paseto_v2_local_encrypt(
+            message, message_len, key, NULL, 0);
+	free(message);
+    if (!encrypted) {
+        perror("paseto_v2_local_encrypt failed");
+        exit(-1);
+    }
+	puts(encrypted);
+    paseto_free(encrypted);
+}

include/paseto.h

@@ -57,8 +57,10 @@ char *paseto_v2_local_encrypt(
  * is not NULL and the encoded message contains a non-zero-length footer, it
  * will be set to a pointer to the decoded footer. It is the callers
  * responsibility to free it.
- * Returns a pointer to the decrypted message. `message_len` is set ti its
- * length. It is the callers responsibility to free it using `paseto_free`.
+ * Returns a pointer to the decrypted message. `message_len` is set to its
+ * length. For convenience, the message is terminated by a NULL byte. This NULL
+ * byte is *not* included in `message_len`. It is the callers responsibility to
+ * free it using `paseto_free`.
  * Returns NULL on error and sets errno.
  * Returns NULL on verification failure.
  */

src/paseto_v2_local.c

@@ -241,6 +241,7 @@ uint8_t *paseto_v2_local_decrypt(
         return NULL;
     }
 
+    // include a null terminator for convenience
     message[internal_message_len] = '\0';
 
     free(pa.base);