lcpex rewrite - alpha

src/lcpex/Contexts.cpp

@@ -0,0 +1,70 @@
+#include "Contexts.h"
+
+
+// converts username to UID
+int username_to_uid( std::string username, int & uid )
+{
+    // assume failure unless proven otherwise
+    int r_code = false;
+
+    struct passwd * pw;
+    if ( ( pw = getpwnam( username.c_str() ) ) != NULL )
+    {
+        // successful user lookup
+        r_code = true;
+        uid = pw->pw_uid;
+    } else {
+        // failed lookup, do nothing, assumed failure
+    }
+    return r_code;
+};
+
+// converts group name to GID
+int groupname_to_gid( std::string groupname, int & gid )
+{
+    int r_code = false;
+
+    struct group * gp;
+    if ( ( gp = getgrnam( groupname.c_str() ) ) != NULL )
+    {
+        r_code = true;
+        gid = gp->gr_gid;
+    } else {
+        // failed lookup, do nothing, assumed failure
+    }
+    return r_code;
+}
+
+// SET PROCESS TO A CERTAIN IDENTITY CONTEXT
+int set_identity_context( std::string user_name, std::string group_name ) {
+    // the UID and GID for the username and groupname provided for context setting
+    int context_user_id;
+    int context_group_id;
+
+    int res = 0;
+
+    // convert username to UID
+    if (! ( res = username_to_uid(user_name, context_user_id ) ) )
+    {
+        return ERROR_NO_SUCH_USER;
+    }
+
+    // convert group name to GID
+    if (! ( res = groupname_to_gid(group_name, context_group_id ) ) )
+    {
+        return ERROR_NO_SUCH_GROUP;
+    }
+
+    if ( ( res = setgid(context_group_id) ) ) {
+        perror("lcpex: setgid failed");
+        return ERROR_SETGID_FAILED;
+    }
+
+    if ( ( res = setuid(context_user_id) ) ) {
+        perror("lcpex: setuid failed");
+        return ERROR_SETUID_FAILED;
+    }
+
+    return ERROR_NONE;
+}
+