Unverified Commit 7091baf0 authored by Tommaso Tocci's avatar Tommaso Tocci
Browse files

intercept chmod,fchmod,fchmodat

parent e77d0fce

include/client/hooks.hpp

+2 −0
Original line number Diff line number Diff line
@@ -40,6 +40,8 @@ int hook_dup2(unsigned int oldfd, unsigned int newfd); 
int hook_dup3(unsigned int oldfd, unsigned int newfd, int flags);

int hook_getdents(unsigned int fd, struct linux_dirent *dirp, unsigned int count);

int hook_mkdirat(int dirfd, const char * cpath, mode_t mode);

int hook_fchmodat(int dirfd, const char* path, mode_t mode);

int hook_fchmod(unsigned int dirfd, mode_t mode);

int hook_chdir(const char* path);

int hook_fchdir(unsigned int fd);

int hook_getcwd(char * buf, unsigned long size);

src/client/hooks.cpp

+33 −0
Original line number Diff line number Diff line
@@ -314,7 +314,40 @@ int hook_mkdirat(int dirfd, const char * cpath, mode_t mode) { 
    }

}



int hook_fchmodat(int dirfd, const char * cpath, mode_t mode) {

    CTX->log()->trace("{}() called dirfd {}, path '{}', mode {}", __func__, dirfd, cpath, mode);



    std::string resolved;

    auto rstatus = CTX->relativize_fd_path(dirfd, cpath, resolved);

    switch(rstatus) {

        case RelativizeStatus::fd_unknown:

            return syscall_no_intercept(SYS_fchmodat, dirfd, cpath, mode);



        case RelativizeStatus::external:

            return syscall_no_intercept(SYS_fchmodat, dirfd, resolved.c_str(), mode);



        case RelativizeStatus::fd_not_a_dir:

            return -ENOTDIR;



        case RelativizeStatus::internal:

            CTX->log()->warn("{}() operation not supported", __func__);

            return -ENOTSUP;



        default:

            CTX->log()->error("{}() relativize status unknown: {}", __func__);

            return -EINVAL;

    }

}



int hook_fchmod(unsigned int fd, mode_t mode) {

    CTX->log()->trace("{}() called with fd {}, mode {}", __func__, fd, mode);

    if (CTX->file_map()->exist(fd)) {

        CTX->log()->warn("{}() operation not supported", __func__);

        return -ENOTSUP;

    }

    return syscall_no_intercept(SYS_fchmod, fd, mode);

}



int hook_chdir(const char * path) {

    CTX->log()->trace("{}() called with path '{}'", __func__, path);

    std::string rel_path;

src/client/intercept.cpp

+17 −0
Original line number Diff line number Diff line
@@ -181,6 +181,23 @@ static inline int hook(long syscall_number, 
                               static_cast<mode_t>(arg1));

        break;



    case SYS_chmod:

        *result = hook_fchmodat(AT_FDCWD,

                                reinterpret_cast<char*>(arg0),

                                static_cast<mode_t>(arg1));

        break;



    case SYS_fchmod:

        *result = hook_fchmod(static_cast<unsigned int>(arg0),

                              static_cast<mode_t>(arg1));

        break;



    case SYS_fchmodat:

        *result = hook_fchmodat(static_cast<unsigned int>(arg0),

                                reinterpret_cast<char*>(arg1),

                                static_cast<mode_t>(arg2));

        break;



    case SYS_chdir:

        *result = hook_chdir(reinterpret_cast<const char *>(arg0));

        break;