ref: 5c1feb0ef0b795e5de71e956f9ccddcd5c4b7f21
dir: /sys/src/cmd/venti/srv/verifyarena.c/
#include "stdinc.h"
#include "dat.h"
#include "fns.h"
static int verbose;
static int fd;
static uchar *data;
static int blocksize;
static int sleepms;
static vlong offset0;
void
usage(void)
{
fprint(2, "usage: verifyarena [-b blocksize] [-s ms] [-v] [arenapart [name...]]\n");
threadexitsall(0);
}
static int
preadblock(uchar *buf, int n, vlong off)
{
int nr, m;
for(nr = 0; nr < n; nr += m){
m = n - nr;
m = pread(fd, &buf[nr], m, offset0+off+nr);
if(m <= 0){
if(m == 0)
werrstr("early eof");
return -1;
}
}
return 0;
}
static int
readblock(uchar *buf, int n)
{
int nr, m;
for(nr = 0; nr < n; nr += m){
m = n - nr;
m = read(fd, &buf[nr], m);
if(m <= 0){
if(m == 0)
werrstr("early eof");
return -1;
}
}
return 0;
}
static void
verifyarena(char *name, vlong len)
{
Arena arena;
ArenaHead head;
DigestState s;
u64int n, e;
u32int bs;
u8int score[VtScoreSize];
fprint(2, "%T verify %s\n", name);
memset(&arena, 0, sizeof arena);
memset(&s, 0, sizeof s);
/*
* read a little bit, which will include the header
*/
if(readblock(data, HeadSize) < 0){
fprint(2, "%T %s: reading header: %r\n", name);
return;
}
sha1(data, HeadSize, nil, &s);
if(unpackarenahead(&head, data) < 0){
fprint(2, "%T %s: corrupt arena header: %r\n", name);
return;
}
if(head.version != ArenaVersion4 && head.version != ArenaVersion5)
fprint(2, "%T %s: warning: unknown arena version %d\n", name, head.version);
if(len != 0 && len != head.size)
fprint(2, "%T %s: warning: unexpected length %lld != %lld\n", name, head.size, len);
if(strcmp(name, "<stdin>") != 0 && strcmp(head.name, name) != 0)
fprint(2, "%T %s: warning: unexpected name %s\n", name, head.name);
/*
* now we know how much to read
* read everything but the last block, which is special
*/
e = head.size - head.blocksize;
bs = blocksize;
for(n = HeadSize; n < e; n += bs){
if(n + bs > e)
bs = e - n;
if(readblock(data, bs) < 0){
fprint(2, "%T %s: read data: %r\n", name);
return;
}
sha1(data, bs, nil, &s);
if(sleepms)
sleep(sleepms);
}
/*
* read the last block update the sum.
* the sum is calculated assuming the slot for the sum is zero.
*/
bs = head.blocksize;
if(readblock(data, bs) < 0){
fprint(2, "%T %s: read last block: %r\n", name);
return;
}
sha1(data, bs-VtScoreSize, nil, &s);
sha1(zeroscore, VtScoreSize, nil, &s);
sha1(nil, 0, score, &s);
/*
* validity check on the trailer
*/
arena.blocksize = head.blocksize;
if(unpackarena(&arena, data) < 0){
fprint(2, "%T %s: corrupt arena trailer: %r\n", name);
return;
}
scorecp(arena.score, &data[arena.blocksize - VtScoreSize]);
if(namecmp(arena.name, head.name) != 0){
fprint(2, "%T %s: wrong name in trailer: %s vs. %s\n",
name, head.name, arena.name);
return;
}
if(arena.version != head.version){
fprint(2, "%T %s: wrong version in trailer: %d vs. %d\n",
name, head.version, arena.version);
return;
}
arena.size = head.size - 2 * head.blocksize;
/*
* check for no checksum or the same
*/
if(scorecmp(score, arena.score) == 0)
fprint(2, "%T %s: verified score\n", name);
else if(scorecmp(zeroscore, arena.score) == 0)
fprint(2, "%T %s: unsealed\n", name);
else{
fprint(2, "%T %s: mismatch checksum - found=%V calculated=%V\n",
name, arena.score, score);
return;
}
printarena(2, &arena);
}
static int
shouldcheck(char *name, char **s, int n)
{
int i;
if(n == 0)
return 1;
for(i=0; i<n; i++){
if(s[i] && strcmp(name, s[i]) == 0){
s[i] = nil;
return 1;
}
}
return 0;
}
void
threadmain(int argc, char *argv[])
{
int i, nline;
char *p, *q, *table, *f[10], line[256];
vlong start, stop;
ArenaPart ap;
Part *part;
needzeroscore();
ventifmtinstall();
blocksize = MaxIoSize;
ARGBEGIN{
case 'b':
blocksize = unittoull(EARGF(usage()));
break;
case 's':
sleepms = atoi(EARGF(usage()));
break;
case 'v':
verbose++;
break;
default:
usage();
break;
}ARGEND
data = vtmalloc(blocksize);
if(argc == 0){
fd = 0;
verifyarena("<stdin>", 0);
threadexitsall(nil);
}
if((part = initpart(argv[0], OREAD)) == nil)
sysfatal("open partition %s: %r", argv[0]);
fd = part->fd;
offset0 = part->offset;
if(preadblock(data, 8192, PartBlank) < 0)
sysfatal("read arena part header: %r");
if(unpackarenapart(&ap, data) < 0)
sysfatal("corrupted arena part header: %r");
fprint(2, "%T # arena part version=%d blocksize=%d arenabase=%d\n",
ap.version, ap.blocksize, ap.arenabase);
ap.tabbase = (PartBlank+HeadSize+ap.blocksize-1)&~(ap.blocksize-1);
ap.tabsize = ap.arenabase - ap.tabbase;
table = malloc(ap.tabsize+1);
if(preadblock((uchar*)table, ap.tabsize, ap.tabbase) < 0)
sysfatal("reading arena part directory: %r");
table[ap.tabsize] = 0;
nline = atoi(table);
p = strchr(table, '\n');
if(p)
p++;
for(i=0; i<nline; i++){
if(p == nil){
fprint(2, "%T warning: unexpected arena table end\n");
break;
}
q = strchr(p, '\n');
if(q)
*q++ = 0;
if(strlen(p) >= sizeof line){
fprint(2, "%T warning: long arena table line: %s\n", p);
p = q;
continue;
}
strcpy(line, p);
memset(f, 0, sizeof f);
if(tokenize(line, f, nelem(f)) < 3){
fprint(2, "%T warning: bad arena table line: %s\n", p);
p = q;
continue;
}
p = q;
if(shouldcheck(f[0], argv+1, argc-1)){
start = strtoull(f[1], 0, 0);
stop = strtoull(f[2], 0, 0);
if(stop <= start){
fprint(2, "%T %s: bad start,stop %lld,%lld\n", f[0], stop, start);
continue;
}
if(seek(fd, offset0+start, 0) < 0)
fprint(2, "%T %s: seek to start: %r\n", f[0]);
verifyarena(f[0], stop - start);
}
}
for(i=1; i<argc; i++)
if(argv[i] != 0)
fprint(2, "%T %s: did not find arena\n", argv[i]);
threadexitsall(nil);
}