diff options
| -rw-r--r-- | util/nvmutil/nvmutil.c | 87 |
1 files changed, 62 insertions, 25 deletions
diff --git a/util/nvmutil/nvmutil.c b/util/nvmutil/nvmutil.c index 6f08a859..cd98a870 100644 --- a/util/nvmutil/nvmutil.c +++ b/util/nvmutil/nvmutil.c @@ -82,11 +82,13 @@ main(int argc, char *argv[]) fprintf(stderr, " %s FILE setchecksum 0|1\n", argv[0]); err(errno = ECANCELED, "Too few arguments"); } + + filename = argv[1]; if (strcmp(COMMAND, "dump") == 0) flags = O_RDONLY; /* write not needed for dump cmd */ else flags = O_RDWR; - filename = argv[1]; + /* Err if files are actually directories; this also prevents unveil allowing directory accesses, which is critical because we only want *file* accesses. */ @@ -104,8 +106,8 @@ main(int argc, char *argv[]) err_if(pledge("stdio rpath wpath", NULL) == -1); } #endif - /* open files, but don't read yet; do pledge after, *then* read */ - openFiles(filename); + + openFiles(filename); /* open files first, to allow harder pledge: */ #ifdef __OpenBSD__ /* OpenBSD sandboxing: https://man.openbsd.org/pledge.2 */ err_if(pledge("stdio", NULL) == -1); @@ -115,9 +117,10 @@ main(int argc, char *argv[]) if (strcmp(COMMAND, op[i].str) == 0) if ((cmd = argc >= op[i].args ? op[i].cmd : NULL)) break; /* function ptr set, as per user cmd */ - if (cmd == cmd_setmac) { /* user wishes to set the MAC address */ - strMac = strRMac; /* random mac */ - if (argc > 3) /* user-supplied mac (can be random) */ + + if (cmd == cmd_setmac) { + strMac = strRMac; /* random MAC */ + if (argc > 3) /* user-supplied MAC (can be random) */ strMac = MAC_ADDRESS; } else if ((cmd != NULL) && (argc > 3)) { /* user-supplied partnum */ err_if((errno = (!((part = PARTN[0] - '0') == 0 || part == 1)) @@ -130,6 +133,7 @@ main(int argc, char *argv[]) if ((gbeFileChanged) && (flags != O_RDONLY) && (cmd != writeGbe)) writeGbe(); /* not called for swap cmd; swap calls writeGbe */ + err_if((errno != 0) && (cmd != cmd_dump)); /* don't err on dump */ return errno; /* errno can be set by the dump command */ } @@ -154,7 +158,9 @@ void openFiles(const char *path) { struct stat st; - xopen(fd, path, flags); + + xopen(fd, path, flags); /* gbe file */ + switch(st.st_size) { case SIZE_8KB: case SIZE_16KB: @@ -165,6 +171,8 @@ openFiles(const char *path) err(errno = ECANCELED, "Invalid file size (not 8/16/128KiB)"); break; } + + /* the MAC address randomiser relies on reading urandom */ xopen(rfd, "/dev/urandom", O_RDONLY); } @@ -173,15 +181,21 @@ void readGbe(void) { if ((cmd == writeGbe) || (cmd == cmd_copy)) - nf = partsize; + nf = partsize; /* read/write the entire block */ else - nf = 128; - skipread[part ^ 1] = (cmd == cmd_copy) | (cmd == cmd_setchecksum) - | (cmd == cmd_brick); - gbe[1] = (gbe[0] = (size_t) buf) + partsize; + nf = 128; /* only read/write the nvm part of the block */ + + if ((cmd == cmd_copy) || (cmd == cmd_setchecksum) || (cmd == cmd_brick)) + skipread[part ^ 1] = 1; /* only read the user-specified part */ + + /* we pread per-part, so each part has its own pointer: */ + gbe[0] = (size_t) buf; + gbe[1] = gbe[0] + partsize; + for (int p = 0; p < 2; p++) { if (skipread[p]) - continue; + continue; /* avoid unnecessary reads */ + err_if(pread(fd, (uint8_t *) gbe[p], nf, p * partsize) == -1); swap(p); /* handle big-endian host CPU */ } @@ -193,12 +207,15 @@ cmd_setmac(void) { if (macAddress(strMac, mac)) err(errno = ECANCELED, "Bad MAC address"); + for (int partnum = 0; partnum < 2; partnum++) { if (!goodChecksum(part = partnum)) continue; - for (int w = 0; w < 3; w++) + + for (int w = 0; w < 3; w++) /* write MAC to gbe part */ setWord(w, partnum, mac[w]); - cmd_setchecksum(); + + cmd_setchecksum(); /* MAC updated; need valid checksum */ } } @@ -207,23 +224,33 @@ int macAddress(const char *strMac, uint16_t *mac) { uint64_t total = 0; - if (strnlen(strMac, 20) == 17) { + if (strnlen(strMac, 20) != 17) + return 1; /* 1 means error */ + for (uint8_t h, i = 0; i < 16; i += 3) { if (i != 15) if (strMac[i + 2] != ':') return 1; + int byte = i / 3; + + /* Update MAC buffer per-nibble from a given string */ for (int nib = 0; nib < 2; nib++, total += h) { if ((h = hextonum(strMac[i + nib])) > 15) - return 1; - if ((byte == 0) && (nib == 1)) - if (strMac[i + nib] == '?') + return 1; /* invalid character, MAC string */ + + /* if random: ensure local-only, unicast MAC */ + if ((byte == 0) && (nib == 1)) /* unicast/local nib */ + if (strMac[i + nib] == '?') /* ?=random */ h = (h & 0xE) | 2; /* local, unicast */ + mac[byte >> 1] |= ((uint16_t ) h) << ((8 * (byte % 2)) + (4 * (nib ^ 1))); } - }} - return ((total == 0) | (mac[0] & 1)); /* multicast/all-zero banned */ + } + + /* do not permit multicast/all-zero MAC: */ + return ((total == 0) || (mac[0] & 1)) ? 1 : 0; } /* convert hex char to char value (0-15) */ @@ -300,7 +327,8 @@ cmd_setchecksum(void) uint16_t val16 = 0; for (int c = 0; c < 0x3F; c++) val16 += word(c, part); - setWord(0x3F, part, NVM_CHECKSUM - val16); + + setWord(0x3F, part, NVM_CHECKSUM - val16); /* correct the checksum */ } /* intentionally set wrong checksum on part */ @@ -326,24 +354,32 @@ goodChecksum(int partnum) uint16_t total = 0; for(int w = 0; w <= 0x3F; w++) total += word(w, partnum); + if (total == NVM_CHECKSUM) return 1; + fprintf(stderr, "WARNING: BAD checksum in part %d\n", partnum); - return (errno = ECANCELED) & 0; + errno = ECANCELED; + return 0; } /* write the nvm parts back to the file */ void writeGbe(void) { - err_if((cmd == writeGbe) && !(goodChecksum(0) || goodChecksum(1))); + if (cmd == writeGbe) /* cmd swap calls writeGbE; need valid checksum */ + err_if(!(goodChecksum(0) || goodChecksum(1))); + for (int p = 0, x = (cmd == writeGbe) ? 1 : 0; p < 2; p++) { if ((!nvmPartChanged[p]) && (cmd != writeGbe)) continue; - swap(p ^ x); + + swap(p ^ x); /* swap bytes on big-endian host CPUs */ + err_if(pwrite(fd, (uint8_t *) gbe[p ^ x], nf, p * partsize) == -1); } + errno = 0; err_if(close(fd) == -1); } @@ -354,6 +390,7 @@ swap(int partnum) { size_t w, x; uint8_t *n = (uint8_t *) gbe[partnum]; + for (w = nf * ((uint8_t *) &e)[0], x = 1; w < nf; w += 2, x += 2) n[w] ^= n[x], n[x] ^= n[w], n[w] ^= n[x]; } |