ref: ad9a404582539cc0d069e71ba2269e35775f0800
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; }