| 1 | #include <u.h> |
| 2 | #include <libc.h> |
| 3 | #include <ureg.h> |
| 4 | #include <mp.h> |
| 5 | #include <libsec.h> |
| 6 | |
| 7 | #include "dat.h" |
| 8 | #include "fns.h" |
| 9 | #include "linux.h" |
| 10 | |
| 11 | enum |
| 12 | { |
| 13 | Mnull, |
| 14 | Mzero, |
| 15 | Mfull, |
| 16 | Mrandom, |
| 17 | Murandom, |
| 18 | Mmax, |
| 19 | }; |
| 20 | |
| 21 | typedef struct Miscfile Miscfile; |
| 22 | struct Miscfile |
| 23 | { |
| 24 | Ufile; |
| 25 | int m; |
| 26 | }; |
| 27 | |
| 28 | static int |
| 29 | path2m(char *path) |
| 30 | { |
| 31 | int m; |
| 32 | |
| 33 | m = -1; |
| 34 | if(strcmp(path, "/dev/null")==0){ |
| 35 | m = Mnull; |
| 36 | } else if(strcmp(path, "/dev/zero")==0){ |
| 37 | m = Mzero; |
| 38 | } else if(strcmp(path, "/dev/full")==0){ |
| 39 | m = Mfull; |
| 40 | } else if(strcmp(path, "/dev/random")==0){ |
| 41 | m = Mrandom; |
| 42 | } else if(strcmp(path, "/dev/urandom")==0){ |
| 43 | m = Murandom; |
| 44 | } |
| 45 | |
| 46 | return m; |
| 47 | } |
| 48 | |
| 49 | static int |
| 50 | openmisc(char *path, int mode, int, Ufile **pf) |
| 51 | { |
| 52 | Miscfile *f; |
| 53 | int m; |
| 54 | |
| 55 | if((m = path2m(path)) < 0) |
| 56 | return -ENOENT; |
| 57 | f = kmallocz(sizeof(*f), 1); |
| 58 | f->ref = 1; |
| 59 | f->mode = mode; |
| 60 | f->path = kstrdup(path); |
| 61 | f->fd = -1; |
| 62 | f->dev = MISCDEV; |
| 63 | f->m = m; |
| 64 | *pf = f; |
| 65 | return 0; |
| 66 | } |
| 67 | |
| 68 | static int |
| 69 | closemisc(Ufile *) |
| 70 | { |
| 71 | return 0; |
| 72 | } |
| 73 | |
| 74 | static int |
| 75 | readmisc(Ufile *f, void *buf, int len, vlong) |
| 76 | { |
| 77 | switch(((Miscfile*)f)->m){ |
| 78 | case Mnull: |
| 79 | return 0; |
| 80 | case Mzero: |
| 81 | memset(buf, 0, len); |
| 82 | return len; |
| 83 | case Mfull: |
| 84 | return -EIO; |
| 85 | case Mrandom: |
| 86 | genrandom(buf, len); |
| 87 | return len; |
| 88 | case Murandom: |
| 89 | prng(buf, len); |
| 90 | return len; |
| 91 | default: |
| 92 | return -EIO; |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | static int |
| 97 | writemisc(Ufile *f, void *, int len, vlong) |
| 98 | { |
| 99 | switch(((Miscfile*)f)->m){ |
| 100 | case Mnull: |
| 101 | case Mzero: |
| 102 | case Mrandom: |
| 103 | case Murandom: |
| 104 | return len; |
| 105 | case Mfull: |
| 106 | return -ENOSPC; |
| 107 | default: |
| 108 | return -EIO; |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | static int |
| 113 | statmisc(char *path, int, Ustat *s) |
| 114 | { |
| 115 | if(path2m(path) < 0) |
| 116 | return -ENOENT; |
| 117 | |
| 118 | s->mode = 0666 | S_IFCHR; |
| 119 | s->uid = current->uid; |
| 120 | s->gid = current->gid; |
| 121 | s->size = 0; |
| 122 | s->ino = hashpath(path); |
| 123 | s->dev = 0; |
| 124 | s->rdev = 0; |
| 125 | s->atime = s->mtime = s->ctime = boottime/1000000000LL; |
| 126 | return 0; |
| 127 | } |
| 128 | |
| 129 | static int |
| 130 | fstatmisc(Ufile *f, Ustat *s) |
| 131 | { |
| 132 | return fsstat(f->path, 0, s); |
| 133 | }; |
| 134 | |
| 135 | static Udev miscdev = |
| 136 | { |
| 137 | .open = openmisc, |
| 138 | .read = readmisc, |
| 139 | .write = writemisc, |
| 140 | .close = closemisc, |
| 141 | .stat = statmisc, |
| 142 | .fstat = fstatmisc, |
| 143 | }; |
| 144 | |
| 145 | void miscdevinit(void) |
| 146 | { |
| 147 | devtab[MISCDEV] = &miscdev; |
| 148 | |
| 149 | fsmount(&miscdev, "/dev/null"); |
| 150 | fsmount(&miscdev, "/dev/zero"); |
| 151 | fsmount(&miscdev, "/dev/full"); |
| 152 | fsmount(&miscdev, "/dev/random"); |
| 153 | fsmount(&miscdev, "/dev/urandom"); |
| 154 | |
| 155 | srand(truerand()); |
| 156 | } |