SIV opertation -- 3

in this project, you will implement a very simple system integrity verifier (SIV) for a Linux system. The goal of the SIV is to detect file system modifications occurring within a directory tree. The SIV outputs statistics and warnings about changes to a report file specified by the user. The SIV can be run either in initialization mode or in verification mode. In initialization mode, the SIV program requires the user to enter a path to a monitored directory, another path to a verification file (outside the monitored directory), a third path to a report file and a hash function (e.g., the SIV must support at least MD-5 and SHA-1 message digests). The program will do the following: a) Verify that the specified monitored directory exists b) Verify that the specified location of the verification file and the report file are outside the monitored directory c) Verify that the specified hash function is supported by your SIV d) If the verification file and/or report file exists already then they will be overwritten. e) Recursively iterate through the directory contents (of arbitrary depth level) and for each file/directory found record the following information in the verification file (it is up to you decide the format used to store records in the verification file): I. Full path to file/directory, including filename II. Size of the file III. Name of user owning the file/directory IV. Name of group owning the file/directory V. Access rights to the file/directory (either octal or symbolic) VI. Last modification date VII. Computed message digest with specified hash function over file contents f) Write to the report file (this must be a text file) a summary of your findings: I. Full pathname to monitored directory II. Full pathname to verification file III. Number of directories parsed IV. Number of files parsed V. Time to complete the initialization mode Verification mode In verification mode, the user provides the path of the verification file and a path to a report file. The program will do the following: a) Verify that the specified verification file exists and, if true, begin parsing the file b) Verify that the specified verification file is outside the monitored directory c) Verify that the specified report file is outside the monitored directory d) If the report file exists already then it shall be overwritten by the new report. e) Recursively iterate through the directory contents (of arbitrary depth level) and verify that it matches exactly the information from the verification file. A warning must be printed to the report file for each entry that diverges from the records in the verification file, along with information about what is different: I. New or removed files/directories II. Files with a different size than recorded (show old size and new size) III. Files with a different message digest than computed before (show old digest and new digest) IV. Files/directories with a different user/group (show old user/group and new user/group) V. Files/directories with modified access rights (show old access rights and new access rights) VI. Files/directories with a different modification date (show old modification date and new modification date) f) Write to the report file (this must be a text file) a summary of your findings I. Full pathname to monitored directory II. Full pathname to verification file III. Full pathname to report file IV. Number of directories parsed V. Number of files parsed VI. Number of warning issued VII. Time to complete the verification mode The program is not allowed to change the verification file when executing in verification mode. For more details text me