added detections for reading/writing shadow file, password database

nursery/get-password-database-entry-on-linux.yml

@@ -4,6 +4,7 @@ rule:
     namespace: host-interaction/session
     authors:
       - michael.hunhoff@mandiant.com
+      - jonathanlepore@google.com
     scopes:
       static: basic block
       dynamic: call
@@ -17,3 +18,8 @@ rule:
         - api: getpwuid_r
         - api: getpwnam
         - api: getpwnam_r
+        - api: getpwent
+        - api: fgetpwent
+        - api: getpwent_r
+        - api: fgetpwent_r
+

nursery/get-shadow-password-file-entry-on-linux.yml

@@ -0,0 +1,21 @@
+rule:
+  meta:
+    name: get shadow password file entry on linux
+    namespace: collection
+    authors:
+      - jonathanlepore@google.com
+    scopes:
+      static: function
+      dynamic: call
+    references:
+      - https://manpages.ubuntu.com/manpages/noble/man3/getspent.3.html
+  features:
+    - and:
+      - os: linux
+      - or:
+        - api: getspent
+        - api: getspent_r
+        - api: fgetspent
+        - api: fgetspent_r
+        - api: getspnam
+        - api: getspnam_r

nursery/set-shadow-password-file-entry-on-linux.yml

@@ -0,0 +1,16 @@
+rule:
+  meta:
+    name: set shadow password file entry on linux
+    namespace: host-interaction/file-system/write
+    authors:
+      - jonathanlepore@google.com
+    scopes:
+      static: function
+      dynamic: call
+    references:
+      - https://manpages.ubuntu.com/manpages/noble/man3/putspent.3.html
+  features:
+    - and:
+      - os: linux
+      - or:
+        - api: putspent