From 3ecd1ba2ce6d085684b537e7b6226eb96cb90718 Mon Sep 17 00:00:00 2001
From: kuangyufei <kuangyufei@126.com>
Date: Fri, 25 Jun 2021 09:40:27 +0800
Subject: [PATCH] =?UTF-8?q?=E8=BF=9B=E7=A8=8B=E6=9D=83=E9=99=90=E6=B3=A8?=
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---
 compat/posix/src/map_error.c   |  2 +-
 compat/posix/src/semaphore.c   |  2 +-
 platform/main.c                |  2 +-
 security/cap/capability.c      | 20 +++++++--------
 security/cap/capability_type.h | 45 ++++++++++++++++++++--------------
 syscall/misc_syscall.c         |  2 +-
 zzz/git/push.sh                |  2 +-
 7 files changed, 42 insertions(+), 33 deletions(-)

diff --git a/compat/posix/src/map_error.c b/compat/posix/src/map_error.c
index 791fc787..d63c80db 100644
--- a/compat/posix/src/map_error.c
+++ b/compat/posix/src/map_error.c
@@ -34,7 +34,7 @@
 #include "los_sem.h"
 #include "los_task.h"
 
-
+//错误适配
 int map_errno(UINT32 err)
 {
     if (err == LOS_OK) {
diff --git a/compat/posix/src/semaphore.c b/compat/posix/src/semaphore.c
index 71b8f32b..c46eebdd 100644
--- a/compat/posix/src/semaphore.c
+++ b/compat/posix/src/semaphore.c
@@ -36,7 +36,7 @@
 
 
 /* Initialize semaphore to value, shared is not supported in Huawei LiteOS. */
-int sem_init(sem_t *sem, int shared, unsigned int value)
+int sem_init(sem_t *sem, int shared, unsigned int value)//初始化信号量，Huawei LiteOS 不支持共享
 {
     UINT32 semHandle = 0;
     UINT32 ret;
diff --git a/platform/main.c b/platform/main.c
index ba5d4d91..b6904c20 100644
--- a/platform/main.c
+++ b/platform/main.c
@@ -154,7 +154,7 @@ LITE_OS_SEC_TEXT_INIT INT32 main(VOID)//由主CPU执行,默认0号CPU 为主CPU
 
     CPU_MAP_SET(0, OsHwIDGet());//设置CPU映射,参数0 代表0号CPU
 
-    OsSchedStart();
+    OsSchedStart();//调度开始
 
     while (1) {
         __asm volatile("wfi");//WFI: wait for Interrupt 等待中断，即下一次中断发生前都在此hold住不干活
diff --git a/security/cap/capability.c b/security/cap/capability.c
index 00eb4a42..de41058a 100644
--- a/security/cap/capability.c
+++ b/security/cap/capability.c
@@ -39,7 +39,7 @@
 #define CAPABILITY_GET_CAP_MASK(x)      (1 << ((x) & 31))
 #define CAPABILITY_MAX                  31
 #define VALID_CAPS(a, b)                (((a) & (~(b))) != 0)
-
+//是否允许访问
 BOOL IsCapPermit(UINT32 capIndex)
 {
     UINT32 capability = OsCurrProcessGet()->capability;
@@ -50,12 +50,12 @@ BOOL IsCapPermit(UINT32 capIndex)
 
     return (capability & (CAPABILITY_GET_CAP_MASK(capIndex)));
 }
-
+//初始化进程安全能力
 VOID OsInitCapability(LosProcessCB *processCB)
 {
     processCB->capability = CAPABILITY_INIT_STAT;
 }
-
+//进程间安全能力的拷贝
 VOID OsCopyCapability(LosProcessCB *from, LosProcessCB *to)
 {
     UINT32 intSave;
@@ -64,27 +64,27 @@ VOID OsCopyCapability(LosProcessCB *from, LosProcessCB *to)
     to->capability = from->capability;
     SCHEDULER_UNLOCK(intSave);
 }
-
+//为进程设置权限项
 UINT32 SysCapSet(UINT32 caps)
 {
     UINT32 intSave;
 
     SCHEDULER_LOCK(intSave);
-    if (!IsCapPermit(CAP_CAPSET)) {
+    if (!IsCapPermit(CAP_CAPSET)) {//先检查进程是否有权限
         SCHEDULER_UNLOCK(intSave);
         return -EPERM;
     }
 
-    if (VALID_CAPS(caps, OsCurrProcessGet()->capability)) {
+    if (VALID_CAPS(caps, OsCurrProcessGet()->capability)) {//验证参数有效性
         SCHEDULER_UNLOCK(intSave);
         return -EPERM;
     }
 
-    OsCurrProcessGet()->capability = caps;
+    OsCurrProcessGet()->capability = caps;//改变当前进程的权限集,相当于自己给自己加减权限
     SCHEDULER_UNLOCK(intSave);
     return LOS_OK;
 }
-
+//获取参数进程的权限集
 UINT32 SysCapGet(pid_t pid, UINT32 *caps)
 {
     UINT32 intSave;
@@ -109,8 +109,8 @@ UINT32 SysCapGet(pid_t pid, UINT32 *caps)
 
     kCaps = processCB->capability;
     SCHEDULER_UNLOCK(intSave);
-
-    if (LOS_ArchCopyToUser(caps, &kCaps, sizeof(UINT32)) != LOS_OK) {
+	//@note_thinking 感觉这里可以不用 LOS_ArchCopyToUser 直接返回kCaps
+    if (LOS_ArchCopyToUser(caps, &kCaps, sizeof(UINT32)) != LOS_OK) {//内核空间向用户空间拷贝 
         return -EFAULT;
     }
 
diff --git a/security/cap/capability_type.h b/security/cap/capability_type.h
index b5163325..1af2778f 100644
--- a/security/cap/capability_type.h
+++ b/security/cap/capability_type.h
@@ -28,42 +28,51 @@
  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-
+/*
+capabilities 翻译为 权限(集)
+Capabilities 机制是在 Linux 内核 2.2 之后引入的，原理很简单，就是将之前与超级用户 root（UID=0）
+关联的特权细分为不同的功能组，Capabilites 作为线程（Linux 并不真正区分进程和线程）的属性存在，
+每个功能组都可以独立启用和禁用。其本质上就是将内核调用分门别类，具有相似功能的内核调用被分到同一组中。
+这样一来，权限检查的过程就变成了：在执行特权操作时，如果线程的有效身份不是 root，
+就去检查其是否具有该特权操作所对应的 capabilities，并以此为依据，决定是否可以执行特权操作。
+capability 作用在进程上,让用户态进程具有内核态进程的某些权限.
+https://blog.csdn.net/alex_yangchuansheng/article/details/102796001
+*/
 #ifndef CAPABILITY_TYPE_H
 #define CAPABILITY_TYPE_H
 
 // posix capabilities
-#define CAP_CHOWN                       0
-#define CAP_DAC_EXECUTE                 1
-#define CAP_DAC_WRITE                   2
-#define CAP_DAC_READ_SEARCH             3
-#define CAP_FOWNER                      4
-#define CAP_KILL                        5
-#define CAP_SETGID                      6
-#define CAP_SETUID                      7
+#define CAP_CHOWN                       0	//修改文件所有者的权限
+#define CAP_DAC_EXECUTE                 1	//具有执行权限
+#define CAP_DAC_WRITE                   2	//具有写权限
+#define CAP_DAC_READ_SEARCH             3	//忽略文件读及目录搜索的 DAC 访问限制
+#define CAP_FOWNER                      4	//忽略文件属主 ID 必须和进程用户 ID 相匹配的限制
+#define CAP_KILL                        5	//允许向其他进程发生信号
+#define CAP_SETGID                      6	//允许设置其他进程组ID
+#define CAP_SETUID                      7	//允许设置其他进程用户ID
 
 // socket capabilities
-#define CAP_NET_BIND_SERVICE            8
-#define CAP_NET_BROADCAST               9
+#define CAP_NET_BIND_SERVICE            8	//允许绑定端口权限
+#define CAP_NET_BROADCAST               9	//允许广播
 #define CAP_NET_ADMIN                   10
 #define CAP_NET_RAW                     11
 
 // fs capabilities
-#define CAP_FS_MOUNT                    12
-#define CAP_FS_FORMAT                   13
+#define CAP_FS_MOUNT                    12	//允许挂载
+#define CAP_FS_FORMAT                   13	//允许格式化
 
 // process capabilities
-#define CAP_SCHED_SETPRIORITY           14
+#define CAP_SCHED_SETPRIORITY           14	//允许设置调度优先级
 
 // time capabilities
-#define CAP_SET_TIMEOFDAY               15
+#define CAP_SET_TIMEOFDAY               15	
 #define CAP_CLOCK_SETTIME               16
 
 // process capabilities
-#define CAP_CAPSET                      17
+#define CAP_CAPSET                      17	//允许改变进程自身的权限集
 
 // reboot capability
-#define CAP_REBOOT                      18
+#define CAP_REBOOT                      18	//允许重新启动系统
 // self deined privileged syscalls
-#define CAP_SHELL_EXEC                  19
+#define CAP_SHELL_EXEC                  19	//自我定义的特权系统调用
 #endif
\ No newline at end of file
diff --git a/syscall/misc_syscall.c b/syscall/misc_syscall.c
index 29b571d9..771e8f0c 100644
--- a/syscall/misc_syscall.c
+++ b/syscall/misc_syscall.c
@@ -84,7 +84,7 @@ int SysInfo(struct sysinfo *info)
     }
     return 0;
 }
-
+//重启系统
 int SysReboot(int magic, int magic2, int type)
 {
     (void)magic;
diff --git a/zzz/git/push.sh b/zzz/git/push.sh
index ebc71de5..c03b53d7 100644
--- a/zzz/git/push.sh
+++ b/zzz/git/push.sh
@@ -1,5 +1,5 @@
 git add -A
-git commit -m  'posix 接口注解. 
+git commit -m  '进程权限注解. 
     百万汉字注解 + 百篇博客分析 => 挖透鸿蒙内核源码
     国内:https://weharmony.21cloudbox.com
     国外:https://weharmony.github.io
-- 
GitLab