diff options
| -rw-r--r-- | nfs/ops.c | 77 |
1 files changed, 76 insertions, 1 deletions
@@ -854,6 +854,80 @@ netfs_attempt_readlink (struct netcred *cred, struct node *np, return err; } +/* For an NFS node NODE, guess whether CRED is able to read or write + it by hoping the server uses permissions bits in the "expected + way". Return the or of O_READ, O_WRITE, and O_EXEC accordingly as + each is possible. */ +static int +guess_mode_use (struct node *np, + struct netcred *cred) +{ + error_t err; + + err = netfs_validate_stat (np, cred); + if (err) + return err; + + if (cred_has_uid (cred, 0)) + return O_READ|O_WRITE|O_EXEC; + else if (cred->nuids == 0 + && (np->nn_stat.st_mode & S_IUSEUNK)) + return + (((np->nn_stat.st_mode & 04000000) ? O_READ : 0) + | ((np->nn_stat.st_mode & 02000000) ? O_WRITE : 0) + | ((np->nn_stat.st_mode & 01000000) ? O_EXEC : 0)); + else if (cred_has_uid (cred, np->nn_stat.st_uid) + || (cred_has_gid (cred, np->nn_stat.st_gid) + && cred_has_uid (cred, np->nn_stat.st_gid))) + /* Owner */ + return + (((np->nn_stat.st_mode & 0400) ? O_READ : 0) + | ((np->nn_stat.st_mode & 0200) ? O_WRITE : 0) + | ((np->nn_stat.st_mode & 0100) ? O_EXEC : 0)); + else if (cred_has_gid (cred, np->nn_stat.st_gid)) + /* Group */ + return + (((np->nn_stat.st_mode & 040) ? O_READ : 0) + | ((np->nn_stat.st_mode & 020) ? O_WRITE : 0) + | ((np->nn_stat.st_mode & 010) ? O_EXEC : 0)); + else + /* Other */ + return + (((np->nn_stat.st_mode & 4) ? O_READ : 0) + | ((np->nn_stat.st_mode & 2) ? O_WRITE : 0) + | ((np->nn_stat.st_mode & 1) ? O_EXEC : 0)); +} + +/* Implement the netfs_check_open_permissions callback as described in + <hurd/netfs.h>. */ +error_t +netfs_check_open_permissions (struct netcred *cred, struct node *np, + int flags, int newnode) +{ + if ((flags & (O_READ|O_WRITE|O_EXEC)) == 0) + return 0; + + if ((flags & (O_READ|O_WRITE|O_EXEC)) + == (flags & guess_mode_use (np, cred))) + return 0; + else + return EACCES; +} + +/* Implement the netfs_report_access callback as described in + <hurd/netfs.h>. */ +void +netfs_report_access (struct netcred *cred, + struct node *np, + int *types) +{ + *types = guess_mode_use (np, cred); +} + + +/* These definitions have unfortunate side effects, don't use them, + clever though they are. */ +#if 0 /* Implement the netfs_check_open_permissions callback as described in <hurd/netfs.h>. */ error_t @@ -863,7 +937,7 @@ netfs_check_open_permissions (struct netcred *cred, struct node *np, char byte; error_t err; size_t len; - + /* Sun derived nfs client implementations attempt to reproduce the server's permission restrictions by hoping they look like Unix, and using that to give errors at open time. Sadly, that loses @@ -989,6 +1063,7 @@ netfs_report_access (struct netcred *cred, netfs_attempt_set_size (cred, np, 0); } } +#endif /* Fetch the complete contents of DIR into a buffer of directs. Set *BUFP to that buffer. *BUFP must be freed by the caller when no |