add nfc pam module

Change-Id: Icc42361f64948e2c2ab082fa973793f19737df2d
Signed-off-by: Loïc Collignon <loic.collignon@iot.bzh>

3 files changed, 185 insertions, 63 deletions

diff --git a/pam_agl/CMakeLists.txt b/pam_agl/CMakeLists.txt
index 17c85be..7cd39cc 100644
--- a/pam_agl/CMakeLists.txt
+++ b/pam_agl/CMakeLists.txt
@@ -25,22 +25,29 @@ include(FindPkgConfig)
 set(PAM_INCLUDE_DIR "/usr/include/")
 set(PAM_LIBRARY "/lib64/libpam.so.0")
 include_directories(${PAM_INCLUDE_DIR})
+if (NOT DEFINED CMAKE_INSTALL_LIBDIR)
+	get_filename_component(CMAKE_INSTALL_LIBDIR ${PAM_LIBRARY} DIRECTORY)
+endif()
 
 # Find json-c
 pkg_check_modules(${JSON_C} REQUIRED json-c)
 include_directories(${${JSON_C}_INCLUDE_DIRS})
 add_compile_options(${${JSON_C}_CFLAGS})
 
-# Add the target
-add_library(pam_agl SHARED pam_agl.c)
-target_link_libraries(pam_agl ${PAM_LIBRARY} ${${JSON_C}_LIBRARIES})
-#list (APPEND link_libraries ${${JSON_C}_LDFLAGS})
-set_property(TARGET pam_agl PROPERTY POSITION_INDEPENDENT_CODE ON)
-set_property(TARGET pam_agl PROPERTY PREFIX "")
+# Add the pam_agl_usb target
+add_library(pam_agl_usb SHARED pam_agl_usb.c)
+target_link_libraries(pam_agl_usb ${PAM_LIBRARY} ${${JSON_C}_LIBRARIES})
+set_property(TARGET pam_agl_usb PROPERTY POSITION_INDEPENDENT_CODE ON)
+set_property(TARGET pam_agl_usb PROPERTY PREFIX "")
 
-if (NOT DEFINED CMAKE_INSTALL_LIBDIR)
-	get_filename_component(CMAKE_INSTALL_LIBDIR ${PAM_LIBRARY} DIRECTORY)
-endif()
+install(TARGETS pam_agl_usb
+	LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}/security/")
+	
+# Add the pam_agl_nfc target
+add_library(pam_agl_nfc SHARED pam_agl_nfc.c)
+target_link_libraries(pam_agl_nfc ${PAM_LIBRARY} ${${JSON_C}_LIBRARIES})
+set_property(TARGET pam_agl_nfc PROPERTY POSITION_INDEPENDENT_CODE ON)
+set_property(TARGET pam_agl_nfc PROPERTY PREFIX "")
 
-install(TARGETS pam_agl
+install(TARGETS pam_agl_nfc
 	LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}/security/")
diff --git a/pam_agl/pam_agl_nfc.c b/pam_agl/pam_agl_nfc.c
new file mode 100644
index 0000000..b25ba5c
--- /dev/null
+++ b/pam_agl/pam_agl_nfc.c
@@ -0,0 +1,152 @@
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <uuid/uuid.h>
+#include <json-c/json.h>
+
+#define PAM_SM_AUTH
+#define PAM_SM_ACCOUNT
+#define PAM_SM_SESSION
+#define PAM_SM_PASSWORD
+#include <security/pam_modules.h>
+#include <security/pam_appl.h>
+
+#include <security/pam_client.h>
+#include <security/pam_ext.h>
+#include <security/pam_filter.h>
+#include <security/pam_misc.h>
+#include <security/pam_modutil.h>
+
+#define DATABASE_FILE "/etc/agl/keys.json"
+
+int authenticate(pam_handle_t* pamh, const char* uid)
+{
+	struct json_object* database;
+	struct json_object* nfc;
+	struct json_object* key;
+
+	database = json_object_from_file(DATABASE_FILE);
+	if (!database)
+	{
+		printf("[PAM DEBUG] Failed to parse the database\n");
+		return PAM_SERVICE_ERR;
+	}
+	
+	if (json_object_object_get_ex(database, "nfc", &nfc))
+	{	
+		if (json_object_object_get_ex(nfc, uid, &key))
+		{
+			printf("[PAM] Key found!\n");
+			printf("[PAM DEBUG] pam_set_item(\"%s\")\n", uid);
+			pam_set_item(pamh, PAM_USER, uid);
+				
+			const char* pam_authtok;
+			if (pam_get_item(pamh, PAM_AUTHTOK, (const void**)&pam_authtok) == PAM_SUCCESS && !pam_authtok)
+				pam_set_item(pamh, PAM_AUTHTOK, uid);
+			
+			json_object_put(database);
+			return PAM_SUCCESS;
+		}
+	}
+	
+	printf("[PAM] Key not found!\n");
+	if (database) json_object_put(database);
+	return PAM_AUTH_ERR;
+}
+
+int check_device(pam_handle_t* pamh, const char* device)
+{
+	char* idkey;
+	int ret;
+	
+	ret = read_device(device, &idkey);
+	if (ret != PAM_SUCCESS) return ret;
+	
+	printf("[PAM DEBUG] Data read:\n%s\n", idkey);
+	
+	json_object* idkey_json = json_tokener_parse(idkey);
+	if (!idkey_json)
+	{
+		free(idkey);
+		printf("[PAM DEBUG] Failed to parse json data!\n");
+		return PAM_SERVICE_ERR;
+	}
+
+	json_object* uuid_json;
+	if(!json_object_object_get_ex(idkey_json, "uuid", &uuid_json))
+	{
+		free(idkey);
+		printf("[PAM DEBUG] The json does not contains a valid uuid\n");
+		return PAM_SERVICE_ERR;
+	}
+
+	const char* uuid = json_object_get_string(uuid_json);
+	printf("[PAM DEBUG] uuid: %s\n", uuid);
+	
+	ret = authenticate(pamh, uuid);
+	free(idkey);
+	json_object_put(idkey_json);
+	return ret;
+}
+
+void log_pam(const char* fname, int flags, int argc, const char** argv, const char* device)
+{
+	printf("[PAM DEBUG] ---------- %s ----------\n", fname);
+	printf("[PAM DEBUG] flags: %d\n", flags);
+	for(int i = 0; i < argc; ++i)
+	{
+		printf("[PAM DEBUG] argv[%d]: %s\n", i, argv[i]);
+	}
+	printf("[PAM DEBUG] device: %s\n", device);
+	printf("[PAM DEBUG] ----------------------------------------\n");
+}
+
+/*!
+	@brief The pam_sm_authenticate function is the service module's implementation
+	of the pam_authenticate(3) interface.
+	This function performs the task of authenticating the user.
+
+	@param[in] pamh Unknown.
+	@param[in] flags PAM_SILENT and/or PAM_DISALLOW_NULL_AUTHTOK.
+	@return PAM_SUCCESS if ok.
+*/
+PAM_EXTERN int pam_sm_authenticate(pam_handle_t* pamh, int flags, int argc, const char** argv)
+{
+	const char* uid = pam_getenv(pamh, "UID");
+	log_pam("pam_sm_authenticate", flags, argc, argv, uid);
+	return authenticate(pamh, uid);
+}
+
+PAM_EXTERN int pam_sm_setcred(pam_handle_t* pamh, int flags, int argc, const char** argv)
+{
+	log_pam("pam_sm_setcred", flags, argc, argv, pam_getenv(pamh, "DEVICE"));
+	return PAM_SUCCESS;
+}
+
+PAM_EXTERN int pam_sm_acct_mgmt(pam_handle_t* pamh, int flags, int argc, const char** argv)
+{
+	log_pam("pam_sm_acct_mgmt", flags, argc, argv, pam_getenv(pamh, "DEVICE"));
+	return PAM_SUCCESS;
+}
+
+PAM_EXTERN int pam_sm_open_session(pam_handle_t* pamh, int flags, int argc, const char** argv)
+{
+	log_pam("pam_sm_open_session", flags, argc, argv, pam_getenv(pamh, "DEVICE"));
+	return PAM_SUCCESS;
+}
+
+PAM_EXTERN int pam_sm_close_session(pam_handle_t* pamh, int flags, int argc, const char** argv)
+{
+	log_pam("pam_sm_close_session", flags, argc, argv, pam_getenv(pamh, "DEVICE"));
+	return PAM_SUCCESS;
+}
+
+PAM_EXTERN int pam_sm_chauthtok(pam_handle_t* pamh, int flags, int argc, const char** argv)
+{
+	log_pam("pam_sm_chauthtok", flags, argc, argv, pam_getenv(pamh, "DEVICE"));
+	return PAM_SUCCESS;
+}
diff --git a/pam_agl/pam_agl.c b/pam_agl/pam_agl_usb.c
index c85979d..7afe73d 100644
--- a/pam_agl/pam_agl.c
+++ b/pam_agl/pam_agl_usb.c
@@ -29,37 +29,6 @@ int is_valid_mn(const char* v)
 	return v && v[0] == 'I' && v[1] == 'D' && v[2] == 'K' && v[3] == 'Y';
 }
 
-char* get_file_content(const char* path)
-{
-	char* buffer;
-	long length;
-	FILE* f;
-	
-	buffer = NULL;
-	length = 0;
-	
-	f = fopen(path, "rb");
-	if (f)
-	{
-		fseek(f, 0, SEEK_END);
-		length = ftell(f);
-		fseek(f, 0, SEEK_SET);
-		buffer = malloc(length + 1);
-		if (buffer)
-		{
-			if (fread (buffer, 1, length, f) != length)
-			{
-				free(buffer);
-				buffer = NULL;
-			}
-			else buffer[length] = 0;
-		}
-		fclose (f);
-	}
-	
-	return buffer;
-}
-
 int read_device(const char* device, char** idkey)
 {
 	int fd;
@@ -90,41 +59,35 @@ int read_device(const char* device, char** idkey)
 
 int authenticate(pam_handle_t* pamh, const char* uuid)
 {
-	char* file_content;
 	struct json_object* database;
+	struct json_object* usb;
 	struct json_object* key;
 
-	file_content = get_file_content(DATABASE_FILE);
-	if (!file_content)
-	{
-		printf("[PAM DEBUG] Failed to read database file (%s)\n", DATABASE_FILE);
-		return PAM_SERVICE_ERR;
-	}
-	
-	database = json_tokener_parse(file_content);
+	database = json_object_from_file(DATABASE_FILE);
 	if (!database)
 	{
 		printf("[PAM DEBUG] Failed to parse the database\n");
 		return PAM_SERVICE_ERR;
 	}
 	
-	if (json_object_object_get_ex(database, uuid, &key))
-	{
-		printf("[PAM] Key found!\n");
-		printf("[PAM DEBUG] pam_set_item(\"%s\")\n", uuid);
-		pam_set_item(pamh, PAM_USER, uuid);
+	if (json_object_object_get_ex(database, "usb", &usb))
+	{	
+		if (json_object_object_get_ex(usb, uuid, &key))
+		{
+			printf("[PAM] Key found!\n");
+			printf("[PAM DEBUG] pam_set_item(\"%s\")\n", uuid);
+			pam_set_item(pamh, PAM_USER, uuid);
+				
+			const char* pam_authtok;
+			if (pam_get_item(pamh, PAM_AUTHTOK, (const void**)&pam_authtok) == PAM_SUCCESS && !pam_authtok)
+				pam_set_item(pamh, PAM_AUTHTOK, uuid);
 			
-		const char* pam_authtok;
-		if (pam_get_item(pamh, PAM_AUTHTOK, (const void**)&pam_authtok) == PAM_SUCCESS && !pam_authtok)
-			pam_set_item(pamh, PAM_AUTHTOK, uuid);
-		
-		json_object_put(database);
-		free(file_content);
-		return PAM_SUCCESS;
+			json_object_put(database);
+			return PAM_SUCCESS;
+		}
 	}
 	
 	printf("[PAM] Key not found!\n");
-	free(file_content);
 	if (database) json_object_put(database);
 	return PAM_AUTH_ERR;
 }