/* * tools.c */ #define NETSNMP_TOOLS_C 1 /* dont re-define malloc wrappers here */ #include #include #include #include #if TIME_WITH_SYS_TIME # ifdef WIN32 # include # else # include # endif # include #else # if HAVE_SYS_TIME_H # include # else # include # endif #endif #ifdef HAVE_SYS_SOCKET_H #include #endif #if HAVE_WINSOCK_H #include #endif #ifdef HAVE_STDLIB_H #include #endif #if HAVE_STRING_H #include #else #include #endif #ifdef HAVE_NETINET_IN_H #include #endif #ifdef HAVE_ARPA_INET_H #include #endif #if HAVE_DMALLOC_H #include #endif #include #include #include #include /* for "internal" definitions */ #include #include #include #ifdef WIN32 /** * This function is a wrapper for the strdup function. */ char * netsnmp_strdup( const char * ptr) { return strdup(ptr); } /** * This function is a wrapper for the calloc function. */ void * netsnmp_calloc(size_t nmemb, size_t size) { return calloc(nmemb, size); } /** * This function is a wrapper for the malloc function. */ void * netsnmp_malloc(size_t size) { return malloc(size); } /** * This function is a wrapper for the realloc function. */ void * netsnmp_realloc( void * ptr, size_t size) { return realloc(ptr, size); } /** * This function is a wrapper for the free function. * It calls free only if the calling parameter has a non-zero value. */ void netsnmp_free( void * ptr) { if (ptr) free(ptr); } #endif /* WIN32 */ /** * This function increase the size of the buffer pointed at by *buf, which is * initially of size *buf_len. Contents are preserved **AT THE BOTTOM END OF * THE BUFFER**. If memory can be (re-)allocated then it returns 1, else it * returns 0. * * @param buf pointer to a buffer pointer * @param buf_len pointer to current size of buffer in bytes * * @note * The current re-allocation algorithm is to increase the buffer size by * whichever is the greater of 256 bytes or the current buffer size, up to * a maximum increase of 8192 bytes. */ int snmp_realloc(u_char ** buf, size_t * buf_len) { u_char *new_buf = NULL; size_t new_buf_len = 0; if (buf == NULL) { return 0; } if (*buf_len <= 255) { new_buf_len = *buf_len + 256; } else if (*buf_len > 255 && *buf_len <= 8191) { new_buf_len = *buf_len * 2; } else if (*buf_len > 8191) { new_buf_len = *buf_len + 8192; } if (*buf == NULL) { new_buf = (u_char *) malloc(new_buf_len); } else { new_buf = (u_char *) realloc(*buf, new_buf_len); } if (new_buf != NULL) { *buf = new_buf; *buf_len = new_buf_len; return 1; } else { return 0; } } int snmp_strcat(u_char ** buf, size_t * buf_len, size_t * out_len, int allow_realloc, const u_char * s) { if (buf == NULL || buf_len == NULL || out_len == NULL) { return 0; } if (s == NULL) { /* * Appending a NULL string always succeeds since it is a NOP. */ return 1; } while ((*out_len + strlen((const char *) s) + 1) >= *buf_len) { if (!(allow_realloc && snmp_realloc(buf, buf_len))) { return 0; } } strcpy((char *) (*buf + *out_len), (const char *) s); *out_len += strlen((char *) (*buf + *out_len)); return 1; } /** zeros memory before freeing it. * * @param *buf Pointer at bytes to free. * @param size Number of bytes in buf. */ void free_zero(void *buf, size_t size) { if (buf) { memset(buf, 0, size); free(buf); } } /* end free_zero() */ /** * Returns pointer to allocaed & set buffer on success, size contains * number of random bytes filled. buf is NULL and *size set to KMT * error value upon failure. * * @param size Number of bytes to malloc() and fill with random bytes. * * @return a malloced buffer * */ u_char * malloc_random(size_t * size) { int rval = SNMPERR_SUCCESS; u_char *buf = (u_char *) calloc(1, *size); if (buf) { rval = sc_random(buf, size); if (rval < 0) { free_zero(buf, *size); buf = NULL; } else { *size = rval; } } return buf; } /* end malloc_random() */ /** Duplicates a memory block. * Copies a existing memory location from a pointer to another, newly malloced, pointer. * @param to Pointer to allocate and copy memory to. * @param from Pointer to copy memory from. * @param size Size of the data to be copied. * * @return SNMPERR_SUCCESS on success, SNMPERR_GENERR on failure. */ int memdup(u_char ** to, const u_char * from, size_t size) { if (to == NULL) return SNMPERR_GENERR; if (from == NULL) { *to = NULL; return SNMPERR_SUCCESS; } if ((*to = (u_char *) malloc(size)) == NULL) return SNMPERR_GENERR; memcpy(*to, from, size); return SNMPERR_SUCCESS; } /* end memdup() */ /** copies a (possible) unterminated string of a given length into a * new buffer and null terminates it as well (new buffer MAY be one * byte longer to account for this */ char * netsnmp_strdup_and_null(const u_char * from, size_t from_len) { u_char *ret; if (from_len == 0 || from[from_len - 1] != '\0') { ret = malloc(from_len + 1); if (!ret) return NULL; ret[from_len] = '\0'; } else { ret = malloc(from_len); if (!ret) return NULL; ret[from_len - 1] = '\0'; } memcpy(ret, from, from_len); return ret; } /** converts binary to hexidecimal * * @param *input Binary data. * @param len Length of binary data. * @param **output NULL terminated string equivalent in hex. * * @return olen Length of output string not including NULL terminator. * * FIX Is there already one of these in the UCD SNMP codebase? * The old one should be used, or this one should be moved to * snmplib/snmp_api.c. */ u_int binary_to_hex(const u_char * input, size_t len, char **output) { u_int olen = (len * 2) + 1; char *s = (char *) calloc(1, olen), *op = s; const u_char *ip = input; while (ip - input < (int) len) { *op++ = VAL2HEX((*ip >> 4) & 0xf); *op++ = VAL2HEX(*ip & 0xf); ip++; } *op = '\0'; *output = s; return olen; } /* end binary_to_hex() */ /** * hex_to_binary2 * @param *input Printable data in base16. * @param len Length in bytes of data. * @param **output Binary data equivalent to input. * * @return SNMPERR_GENERR on failure, otherwise length of allocated string. * * Input of an odd length is right aligned. * * FIX Another version of "hex-to-binary" which takes odd length input * strings. It also allocates the memory to hold the binary data. * Should be integrated with the official hex_to_binary() function. */ int hex_to_binary2(const u_char * input, size_t len, char **output) { u_int olen = (len / 2) + (len % 2); char *s = (char *) calloc(1, (olen) ? olen : 1), *op = s; const u_char *ip = input; *output = NULL; *op = 0; if (len % 2) { if (!isxdigit(*ip)) goto hex_to_binary2_quit; *op++ = HEX2VAL(*ip); ip++; } while (ip - input < (int) len) { if (!isxdigit(*ip)) goto hex_to_binary2_quit; *op = HEX2VAL(*ip) << 4; ip++; if (!isxdigit(*ip)) goto hex_to_binary2_quit; *op++ += HEX2VAL(*ip); ip++; } *output = s; return olen; hex_to_binary2_quit: free_zero(s, olen); return -1; } /* end hex_to_binary2() */ int snmp_decimal_to_binary(u_char ** buf, size_t * buf_len, size_t * out_len, int allow_realloc, const char *decimal) { int subid = 0; const char *cp = decimal; if (buf == NULL || buf_len == NULL || out_len == NULL || decimal == NULL) { return 0; } while (*cp != '\0') { if (isspace((int) *cp) || *cp == '.') { cp++; continue; } if (!isdigit((int) *cp)) { return 0; } if ((subid = atoi(cp)) > 255) { return 0; } if ((*out_len >= *buf_len) && !(allow_realloc && snmp_realloc(buf, buf_len))) { return 0; } *(*buf + *out_len) = (u_char) subid; (*out_len)++; while (isdigit((int) *cp)) { cp++; } } return 1; } /** * convert an ASCII hex string (with specified delimiters) to binary * * @param buf address of a pointer (pointer to pointer) for the output buffer. * If allow_realloc is set, the buffer may be grown via snmp_realloc * to accomodate the data. * * @param buf_len pointer to a size_t containing the initial size of buf. * * @param out_len On input, a pointer to a size_t indicating an offset into buf. * The binary data will be stored at this offset. * On output, this pointer will have updated the offset to be * the first byte after the converted data. * * @param allow_realloc If true, the buffer can be reallocated. If false, and * the buffer is not large enough to contain the string, * an error will be returned. * * @param hex pointer to hex string to be converted. May be prefixed by * "0x" or "0X". * * @param delim point to a string of allowed delimiters between bytes. * If not specified, any non-hex characters will be an error. * * @retval 1 success * @retval 0 error */ int netsnmp_hex_to_binary(u_char ** buf, size_t * buf_len, size_t * out_len, int allow_realloc, const char *hex, const char *delim) { int subid = 0; const char *cp = hex; if (buf == NULL || buf_len == NULL || out_len == NULL || hex == NULL) { return 0; } if ((*cp == '0') && ((*(cp + 1) == 'x') || (*(cp + 1) == 'X'))) { cp += 2; } while (*cp != '\0') { if (!isxdigit((int) *cp)) { if ((NULL != delim) && (NULL != strchr(delim, *cp))) { cp++; continue; } return 0; } if (sscanf(cp, "%2x", &subid) == 0) { return 0; } /* * if we dont' have enough space, realloc. * (snmp_realloc will adjust buf_len to new size) */ if ((*out_len >= *buf_len) && !(allow_realloc && snmp_realloc(buf, buf_len))) { return 0; } *(*buf + *out_len) = (u_char) subid; (*out_len)++; if (*++cp == '\0') { /* * Odd number of hex digits is an error. */ return 0; } else { cp++; } } return 1; } /** * convert an ASCII hex string to binary * * @note This is a wrapper which calls netsnmp_hex_to_binary with a * delimiter string of " ". * * See netsnmp_hex_to_binary for parameter descriptions. * * @retval 1 success * @retval 0 error */ int snmp_hex_to_binary(u_char ** buf, size_t * buf_len, size_t * out_len, int allow_realloc, const char *hex) { return netsnmp_hex_to_binary(buf, buf_len, out_len, allow_realloc, hex, " "); } /*******************************************************************-o-****** * dump_chunk * * Parameters: * *title (May be NULL.) * *buf * size */ void dump_chunk(const char *debugtoken, const char *title, const u_char * buf, int size) { u_int printunit = 64; /* XXX Make global. */ char chunk[SNMP_MAXBUF], *s, *sp; if (title && (*title != '\0')) { DEBUGMSGTL((debugtoken, "%s\n", title)); } memset(chunk, 0, SNMP_MAXBUF); size = binary_to_hex(buf, size, &s); sp = s; while (size > 0) { if (size > (int) printunit) { strncpy(chunk, sp, printunit); chunk[printunit] = '\0'; DEBUGMSGTL((debugtoken, "\t%s\n", chunk)); } else { DEBUGMSGTL((debugtoken, "\t%s\n", sp)); } sp += printunit; size -= printunit; } SNMP_FREE(s); } /* end dump_chunk() */ /*******************************************************************-o-****** * dump_snmpEngineID * * Parameters: * *estring * *estring_len * * Returns: * Allocated memory pointing to a string of buflen char representing * a printf'able form of the snmpEngineID. * * -OR- NULL on error. * * * Translates the snmpEngineID TC into a printable string. From RFC 2271, * Section 5 (pp. 36-37): * * First bit: 0 Bit string structured by means non-SNMPv3. * 1 Structure described by SNMPv3 SnmpEngineID TC. * * Bytes 1-4: Enterprise ID. (High bit of first byte is ignored.) * * Byte 5: 0 (RESERVED by IANA.) * 1 IPv4 address. ( 4 octets) * 2 IPv6 address. ( 16 octets) * 3 MAC address. ( 6 octets) * 4 Locally defined text. (0-27 octets) * 5 Locally defined octets. (0-27 octets) * 6-127 (RESERVED for enterprise.) * * Bytes 6-32: (Determined by byte 5.) * * * Non-printable characters are given in hex. Text is given in quotes. * IP and MAC addresses are given in standard (UN*X) conventions. Sections * are comma separated. * * esp, remaining_len and s trace the state of the constructed buffer. * s will be defined if there is something to return, and it will point * to the end of the constructed buffer. * * * ASSUME "Text" means printable characters. * * XXX Must the snmpEngineID always have a minimum length of 12? * (Cf. part 2 of the TC definition.) * XXX Does not enforce upper-bound of 32 bytes. * XXX Need a switch to decide whether to use DNS name instead of a simple * IP address. * * FIX Use something other than snprint_hexstring which doesn't add * trailing spaces and (sometimes embedded) newlines... */ #ifdef SNMP_TESTING_CODE char * dump_snmpEngineID(const u_char * estring, size_t * estring_len) { #define eb(b) ( *(esp+b) & 0xff ) int rval = SNMPERR_SUCCESS, gotviolation = 0, slen = 0; u_int remaining_len; char buf[SNMP_MAXBUF], *s = NULL, *t; const u_char *esp = estring; struct in_addr iaddr; /* * Sanity check. */ if (!estring || (*estring_len <= 0)) { QUITFUN(SNMPERR_GENERR, dump_snmpEngineID_quit); } remaining_len = *estring_len; memset(buf, 0, SNMP_MAXBUF); /* * Test first bit. Return immediately with a hex string, or * begin by formatting the enterprise ID. */ if (!(*esp & 0x80)) { snprint_hexstring(buf, SNMP_MAXBUF, esp, remaining_len); s = strchr(buf, '\0'); s -= 1; goto dump_snmpEngineID_quit; } s = buf; s += sprintf(s, "enterprise %d, ", ((*(esp + 0) & 0x7f) << 24) | ((*(esp + 1) & 0xff) << 16) | ((*(esp + 2) & 0xff) << 8) | ((*(esp + 3) & 0xff))); /* * XXX Ick. */ if (remaining_len < 5) { /* XXX Violating string. */ goto dump_snmpEngineID_quit; } esp += 4; /* Incremented one more in the switch below. */ remaining_len -= 5; /* * Act on the fifth byte. */ switch ((int) *esp++) { case 1: /* IPv4 address. */ if (remaining_len < 4) goto dump_snmpEngineID_violation; memcpy(&iaddr.s_addr, esp, 4); if (!(t = inet_ntoa(iaddr))) goto dump_snmpEngineID_violation; s += sprintf(s, "%s", t); esp += 4; remaining_len -= 4; break; case 2: /* IPv6 address. */ if (remaining_len < 16) goto dump_snmpEngineID_violation; s += sprintf(s, "%02X%02X %02X%02X %02X%02X %02X%02X::" "%02X%02X %02X%02X %02X%02X %02X%02X", eb(0), eb(1), eb(2), eb(3), eb(4), eb(5), eb(6), eb(7), eb(8), eb(9), eb(10), eb(11), eb(12), eb(13), eb(14), eb(15)); esp += 16; remaining_len -= 16; break; case 3: /* MAC address. */ if (remaining_len < 6) goto dump_snmpEngineID_violation; s += sprintf(s, "%02X:%02X:%02X:%02X:%02X:%02X", eb(0), eb(1), eb(2), eb(3), eb(4), eb(5)); esp += 6; remaining_len -= 6; break; case 4: /* Text. */ /* * Doesn't exist on all (many) architectures */ /* * s += snprintf(s, remaining_len+3, "\"%s\"", esp); */ s += sprintf(s, "\"%s\"", esp); goto dump_snmpEngineID_quit; break; /*NOTREACHED*/ case 5: /* Octets. */ snprint_hexstring(s, (SNMP_MAXBUF - (s-buf)), esp, remaining_len); s = strchr(buf, '\0'); s -= 1; goto dump_snmpEngineID_quit; break; /*NOTREACHED*/ dump_snmpEngineID_violation: case 0: /* Violation of RESERVED, * * -OR- of expected length. */ gotviolation = 1; s += sprintf(s, "!!! "); default: /* Unknown encoding. */ if (!gotviolation) { s += sprintf(s, "??? "); } snprint_hexstring(s, (SNMP_MAXBUF - (s-buf)), esp, remaining_len); s = strchr(buf, '\0'); s -= 1; goto dump_snmpEngineID_quit; } /* endswitch */ /* * Cases 1-3 (IP and MAC addresses) should not have trailing * octets, but perhaps they do. Throw them in too. XXX */ if (remaining_len > 0) { s += sprintf(s, " (??? "); snprint_hexstring(s, (SNMP_MAXBUF - (s-buf)), esp, remaining_len); s = strchr(buf, '\0'); s -= 1; s += sprintf(s, ")"); } dump_snmpEngineID_quit: if (s) { slen = s - buf + 1; s = calloc(1, slen); memcpy(s, buf, (slen) - 1); } memset(buf, 0, SNMP_MAXBUF); /* XXX -- Overkill? XXX: Yes! */ return s; #undef eb } /* end dump_snmpEngineID() */ #endif /* SNMP_TESTING_CODE */ /** * create a new time marker. * NOTE: Caller must free time marker when no longer needed. */ marker_t atime_newMarker(void) { marker_t pm = (marker_t) calloc(1, sizeof(struct timeval)); gettimeofday((struct timeval *) pm, 0); return pm; } /** * set a time marker. */ void atime_setMarker(marker_t pm) { if (!pm) return; gettimeofday((struct timeval *) pm, 0); } /** * Returns the difference (in msec) between the two markers */ long atime_diff(marker_t first, marker_t second) { struct timeval *tv1, *tv2, diff; tv1 = (struct timeval *) first; tv2 = (struct timeval *) second; diff.tv_sec = tv2->tv_sec - tv1->tv_sec - 1; diff.tv_usec = tv2->tv_usec - tv1->tv_usec + 1000000; return (diff.tv_sec * 1000 + diff.tv_usec / 1000); } /** * Returns the difference (in u_long msec) between the two markers */ u_long uatime_diff(marker_t first, marker_t second) { struct timeval *tv1, *tv2, diff; tv1 = (struct timeval *) first; tv2 = (struct timeval *) second; diff.tv_sec = tv2->tv_sec - tv1->tv_sec - 1; diff.tv_usec = tv2->tv_usec - tv1->tv_usec + 1000000; return (((u_long) diff.tv_sec) * 1000 + diff.tv_usec / 1000); } /** * Returns the difference (in u_long 1/100th secs) between the two markers * (functionally this is what sysUpTime needs) */ u_long uatime_hdiff(marker_t first, marker_t second) { struct timeval *tv1, *tv2, diff; u_long res; tv1 = (struct timeval *) first; tv2 = (struct timeval *) second; diff.tv_sec = tv2->tv_sec - tv1->tv_sec - 1; diff.tv_usec = tv2->tv_usec - tv1->tv_usec + 1000000; res = ((u_long) diff.tv_sec) * 100 + diff.tv_usec / 10000; return res; } /** * Test: Has (marked time plus delta) exceeded current time (in msec) ? * Returns 0 if test fails or cannot be tested (no marker). */ int atime_ready(marker_t pm, int deltaT) { marker_t now; long diff; if (!pm) return 0; now = atime_newMarker(); diff = atime_diff(pm, now); free(now); if (diff < deltaT) return 0; return 1; } /** * Test: Has (marked time plus delta) exceeded current time (in msec) ? * Returns 0 if test fails or cannot be tested (no marker). */ int uatime_ready(marker_t pm, unsigned int deltaT) { marker_t now; u_long diff; if (!pm) return 0; now = atime_newMarker(); diff = uatime_diff(pm, now); free(now); if (diff < deltaT) return 0; return 1; } /* * Time-related utility functions */ /** * Return the number of timeTicks since the given marker */ int marker_tticks(marker_t pm) { int res; marker_t now = atime_newMarker(); res = atime_diff(pm, now); free(now); return res / 10; /* atime_diff works in msec, not csec */ } int timeval_tticks(struct timeval *tv) { return marker_tticks((marker_t) tv); } /** * Non Windows: Returns a pointer to the desired environment variable * or NULL if the environment variable does not exist. * * Windows: Returns a pointer to the desired environment variable * if it exists. If it does not, the variable is looked up * in the registry in HKCU\Net-SNMP or HKLM\Net-SNMP * (whichever it finds first) and stores the result in the * environment variable. It then returns a pointer to * environment variable. */ char *netsnmp_getenv(const char *name) { #ifndef WIN32 return (getenv(name)); #else char *temp = NULL; HKEY hKey; unsigned char * key_value = NULL; DWORD key_value_size = 0; DWORD key_value_type = 0; DWORD getenv_worked = 0; DEBUGMSGTL(("read_config", "netsnmp_getenv called with name: %s\n",name)); if (!(name)) return NULL; /* Try environment variable first */ temp = getenv(name); if (temp) { getenv_worked = 1; DEBUGMSGTL(("read_config", "netsnmp_getenv will return from ENV: %s\n",temp)); } /* Next try HKCU */ if (temp == NULL) { if (RegOpenKeyExA( HKEY_CURRENT_USER, "SOFTWARE\\Net-SNMP", 0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS) { if (RegQueryValueExA( hKey, name, NULL, &key_value_type, NULL, /* Just get the size */ &key_value_size) == ERROR_SUCCESS) { if (key_value) SNMP_FREE(key_value); /* Allocate memory needed +1 to allow RegQueryValueExA to NULL terminate the * string data in registry is missing one (which is unlikely). */ key_value = (char *) malloc((sizeof(char) * key_value_size)+sizeof(char)); if (RegQueryValueExA( hKey, name, NULL, &key_value_type, key_value, &key_value_size) == ERROR_SUCCESS) { } temp = key_value; } RegCloseKey(hKey); if (temp) DEBUGMSGTL(("read_config", "netsnmp_getenv will return from HKCU: %s\n",temp)); } } /* Next try HKLM */ if (temp == NULL) { if (RegOpenKeyExA( HKEY_LOCAL_MACHINE, "SOFTWARE\\Net-SNMP", 0, KEY_QUERY_VALUE, &hKey) == ERROR_SUCCESS) { if (RegQueryValueExA( hKey, name, NULL, &key_value_type, NULL, /* Just get the size */ &key_value_size) == ERROR_SUCCESS) { if (key_value) SNMP_FREE(key_value); /* Allocate memory needed +1 to allow RegQueryValueExA to NULL terminate the * string data in registry is missing one (which is unlikely). */ key_value = (char *) malloc((sizeof(char) * key_value_size)+sizeof(char)); if (RegQueryValueExA( hKey, name, NULL, &key_value_type, key_value, &key_value_size) == ERROR_SUCCESS) { } temp = key_value; } RegCloseKey(hKey); if (temp) DEBUGMSGTL(("read_config", "netsnmp_getenv will return from HKLM: %s\n",temp)); } } if (temp && !getenv_worked) { setenv(name, temp, 1); SNMP_FREE(temp); } DEBUGMSGTL(("read_config", "netsnmp_getenv returning: %s\n",getenv(name))); return(getenv(name)); #endif }