ref: 2707beb7b46cf29fb1ebafad33edf8d48041ed50
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); }