ref: ee4955c879ef4c95c9cd15650fd9768a08c5fda4
dir: /libauthsrv/readnvram.c/
#include <u.h>
#include <libc.h>
#include <authsrv.h>
static long finddosfile(int, char*);
static int
check(void *x, int len, uchar sum, char *msg)
{
if(nvcsum(x, len) == sum)
return 0;
memset(x, 0, len);
fprint(2, "%s\n", msg);
return 1;
}
/*
* get key info out of nvram. since there isn't room in the PC's nvram use
* a disk partition there.
*/
static struct {
char *cputype;
char *file;
int off;
int len;
} nvtab[] = {
"sparc", "#r/nvram", 1024+850, sizeof(Nvrsafe),
"pc", "#S/sdC0/nvram", 0, sizeof(Nvrsafe),
"pc", "#S/sdC0/9fat", -1, sizeof(Nvrsafe),
"pc", "#S/sd00/nvram", 0, sizeof(Nvrsafe),
"pc", "#S/sd00/9fat", -1, sizeof(Nvrsafe),
"pc", "#S/sd01/nvram", 0, sizeof(Nvrsafe),
"pc", "#S/sd01/9fat", -1, sizeof(Nvrsafe),
"pc", "#f/fd0disk", -1, 512, /* 512: #f requires whole sector reads */
"pc", "#f/fd1disk", -1, 512,
"mips", "#r/nvram", 1024+900, sizeof(Nvrsafe),
"power", "#F/flash/flash0", 0x300000, sizeof(Nvrsafe),
"power", "#r/nvram", 4352, sizeof(Nvrsafe), /* OK for MTX-604e */
"debug", "/tmp/nvram", 0, sizeof(Nvrsafe),
};
static char*
readcons(char *prompt, char *def, int raw, char *buf, int nbuf)
{
int fdin, fdout, ctl, n, m;
char line[10];
fdin = open("/dev/cons", OREAD);
if(fdin < 0)
fdin = 0;
fdout = open("/dev/cons", OWRITE);
if(fdout < 0)
fdout = 1;
if(def != nil)
fprint(fdout, "%s[%s]: ", prompt, def);
else
fprint(fdout, "%s: ", prompt);
if(raw){
ctl = open("/dev/consctl", OWRITE);
if(ctl >= 0)
write(ctl, "rawon", 5);
} else
ctl = -1;
m = 0;
for(;;){
n = read(fdin, line, 1);
if(n == 0){
close(ctl);
werrstr("readcons: EOF");
return nil;
}
if(n < 0){
close(ctl);
werrstr("can't read cons");
return nil;
}
if(line[0] == 0x7f)
exits(0);
if(n == 0 || line[0] == '\n' || line[0] == '\r'){
if(raw){
write(ctl, "rawoff", 6);
write(fdout, "\n", 1);
close(ctl);
}
buf[m] = '\0';
if(buf[0]=='\0' && def)
strcpy(buf, def);
return buf;
}
if(line[0] == '\b'){
if(m > 0)
m--;
}else if(line[0] == 0x15){ /* ^U: line kill */
m = 0;
if(def != nil)
fprint(fdout, "%s[%s]: ", prompt, def);
else
fprint(fdout, "%s: ", prompt);
}else{
if(m >= nbuf-1){
fprint(fdout, "line too long\n");
m = 0;
if(def != nil)
fprint(fdout, "%s[%s]: ", prompt, def);
else
fprint(fdout, "%s: ", prompt);
}else
buf[m++] = line[0];
}
}
return buf; /* how does this happen */
}
/*
* get key info out of nvram. since there isn't room in the PC's nvram use
* a disk partition there.
*/
int
readnvram(Nvrsafe *safep, int flag)
{
char buf[1024], in[128], *cputype, *nvrfile, *nvrlen, *nvroff, *v[2];
int fd, err, i, safeoff, safelen;
Nvrsafe *safe;
err = 0;
memset(safep, 0, sizeof(*safep));
nvrfile = getenv("nvram");
cputype = getenv("cputype");
if(cputype == nil)
cputype = "mips";
if(strcmp(cputype, "386")==0 || strcmp(cputype, "alpha")==0)
cputype = "pc";
safe = (Nvrsafe*)buf;
fd = -1;
safeoff = -1;
safelen = -1;
if(nvrfile != nil){
/* accept device and device!file */
i = gettokens(nvrfile, v, nelem(v), "!");
fd = open(v[0], ORDWR);
safelen = sizeof(Nvrsafe);
if(strstr(v[0], "/9fat") == nil)
safeoff = 0;
nvrlen = getenv("nvrlen");
if(nvrlen != nil)
safelen = atoi(nvrlen);
nvroff = getenv("nvroff");
if(nvroff != nil){
if(strcmp(nvroff, "dos") == 0)
safeoff = -1;
else
safeoff = atoi(nvroff);
}
if(safeoff < 0 && fd >= 0){
safelen = 512;
safeoff = finddosfile(fd, i == 2 ? v[1] : "plan9.nvr");
if(safeoff < 0){
close(fd);
fd = -1;
}
}
free(nvrfile);
if(nvrlen != nil)
free(nvrlen);
if(nvroff != nil)
free(nvroff);
}else{
for(i=0; i<nelem(nvtab); i++){
if(strcmp(cputype, nvtab[i].cputype) != 0)
continue;
if((fd = open(nvtab[i].file, ORDWR)) < 0)
continue;
safeoff = nvtab[i].off;
safelen = nvtab[i].len;
if(safeoff == -1){
safeoff = finddosfile(fd, "plan9.nvr");
if(safeoff < 0){
close(fd);
fd = -1;
continue;
}
}
break;
}
}
if(fd < 0
|| seek(fd, safeoff, 0) < 0
|| read(fd, buf, safelen) != safelen){
err = 1;
if(flag&(NVwrite|NVwriteonerr))
fprint(2, "can't read nvram: %r\n");
memset(safep, 0, sizeof(*safep));
safe = safep;
}else{
*safep = *safe;
safe = safep;
err |= check(safe->machkey, DESKEYLEN, safe->machsum, "bad nvram key");
// err |= check(safe->config, CONFIGLEN, safe->configsum, "bad secstore key");
err |= check(safe->authid, ANAMELEN, safe->authidsum, "bad authentication id");
err |= check(safe->authdom, DOMLEN, safe->authdomsum, "bad authentication domain");
}
if((flag&NVwrite) || (err && (flag&NVwriteonerr))){
readcons("authid", nil, 0, safe->authid, sizeof(safe->authid));
readcons("authdom", nil, 0, safe->authdom, sizeof(safe->authdom));
readcons("secstore key", nil, 1, safe->config, sizeof(safe->config));
for(;;){
if(readcons("password", nil, 1, in, sizeof in) == nil)
goto Out;
if(passtokey(safe->machkey, in))
break;
}
safe->machsum = nvcsum(safe->machkey, DESKEYLEN);
safe->configsum = nvcsum(safe->config, CONFIGLEN);
safe->authidsum = nvcsum(safe->authid, sizeof(safe->authid));
safe->authdomsum = nvcsum(safe->authdom, sizeof(safe->authdom));
*(Nvrsafe*)buf = *safe;
if(seek(fd, safeoff, 0) < 0
|| write(fd, buf, safelen) != safelen){
fprint(2, "can't write key to nvram: %r\n");
err = 1;
}else
err = 0;
}
Out:
close(fd);
return err ? -1 : 0;
}
typedef struct Dosboot Dosboot;
struct Dosboot{
uchar magic[3]; /* really an xx86 JMP instruction */
uchar version[8];
uchar sectsize[2];
uchar clustsize;
uchar nresrv[2];
uchar nfats;
uchar rootsize[2];
uchar volsize[2];
uchar mediadesc;
uchar fatsize[2];
uchar trksize[2];
uchar nheads[2];
uchar nhidden[4];
uchar bigvolsize[4];
uchar driveno;
uchar reserved0;
uchar bootsig;
uchar volid[4];
uchar label[11];
uchar type[8];
};
#define GETSHORT(p) (((p)[1]<<8) | (p)[0])
#define GETLONG(p) ((GETSHORT((p)+2) << 16) | GETSHORT((p)))
typedef struct Dosdir Dosdir;
struct Dosdir
{
char name[8];
char ext[3];
uchar attr;
uchar reserved[10];
uchar time[2];
uchar date[2];
uchar start[2];
uchar length[4];
};
static char*
dosparse(char *from, char *to, int len)
{
char c;
memset(to, ' ', len);
if(from == 0)
return 0;
while(len-- > 0){
c = *from++;
if(c == '.')
return from;
if(c == 0)
break;
if(c >= 'a' && c <= 'z')
*to++ = c + 'A' - 'a';
else
*to++ = c;
}
return 0;
}
/*
* return offset of first file block
*
* This is a very simplistic dos file system. It only
* works on floppies, only looks in the root, and only
* returns a pointer to the first block of a file.
*
* This exists for cpu servers that have no hard disk
* or nvram to store the key on.
*
* Please don't make this any smarter: it stays resident
* and I'ld prefer not to waste the space on something that
* runs only at boottime -- presotto.
*/
static long
finddosfile(int fd, char *file)
{
uchar secbuf[512];
char name[8];
char ext[3];
Dosboot *b;
Dosdir *root, *dp;
int nroot, sectsize, rootoff, rootsects, n;
/* dos'ize file name */
file = dosparse(file, name, 8);
dosparse(file, ext, 3);
/* read boot block, check for sanity */
b = (Dosboot*)secbuf;
if(read(fd, secbuf, sizeof(secbuf)) != sizeof(secbuf))
return -1;
if(b->magic[0] != 0xEB || b->magic[1] != 0x3C || b->magic[2] != 0x90)
return -1;
sectsize = GETSHORT(b->sectsize);
if(sectsize != 512)
return -1;
rootoff = (GETSHORT(b->nresrv) + b->nfats*GETSHORT(b->fatsize)) * sectsize;
if(seek(fd, rootoff, 0) < 0)
return -1;
nroot = GETSHORT(b->rootsize);
rootsects = (nroot*sizeof(Dosdir)+sectsize-1)/sectsize;
if(rootsects <= 0 || rootsects > 64)
return -1;
/*
* read root. it is contiguous to make stuff like
* this easier
*/
root = malloc(rootsects*sectsize);
if(read(fd, root, rootsects*sectsize) != rootsects*sectsize)
return -1;
n = -1;
for(dp = root; dp < &root[nroot]; dp++)
if(memcmp(name, dp->name, 8) == 0 && memcmp(ext, dp->ext, 3) == 0){
n = GETSHORT(dp->start);
break;
}
free(root);
if(n < 0)
return -1;
/*
* dp->start is in cluster units, not sectors. The first
* cluster is cluster 2 which starts immediately after the
* root directory
*/
return rootoff + rootsects*sectsize + (n-2)*sectsize*b->clustsize;
}