/* * * Wireless daemon for Linux * * Copyright (C) 2014-2019 Intel Corporation. All rights reserved. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * */ #ifdef HAVE_CONFIG_H #include #endif #include #include #include #include #include #include #include #include "src/util.h" const char *util_ssid_to_utf8(size_t len, const uint8_t *ssid) { static char buf[3* 32 + 1]; size_t i = 0, pos = 0; const uint8_t *start = ssid, *end; memset(buf, 0, sizeof(buf)); if (len > 32) goto no_ssid; while (i < len && !ssid[i]) i++; if (i == len) goto no_ssid; i = len; while (i && (!l_utf8_validate((const char *)start, i, (const char **)&end))) { const char replacement[] = { 0xEF, 0xBF, 0xBD }; int bytes = end - start; memcpy(&buf[pos], start, bytes); pos += bytes; memcpy(&buf[pos], replacement, sizeof(replacement)); pos += sizeof(replacement); start = end + 1; i -= (bytes + 1); } if (i) { memcpy(&buf[pos], start, i); pos += i; } no_ssid: buf[pos] = '\0'; return buf; } bool util_ssid_is_utf8(size_t len, const uint8_t *ssid) { if (len > 32) return false; return l_utf8_validate((const char *)ssid, len, NULL); } /* * Checks whether this is a hidden SSID. Two conditions are checked: * 1. If the SSID is length 0 * 2. If the SSID length > 0 and all bytes are 0 * * The length is not sanitized so the caller must have sanitized the arguments * beforehand. */ bool util_ssid_is_hidden(size_t len, const uint8_t *ssid) { if (!len) return true; return l_memeqzero(ssid, len); } const char *util_address_to_string(const uint8_t *addr) { static char str[18]; sprintf(str, "%02x:%02x:%02x:%02x:%02x:%02x", addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]); return str; } bool util_string_to_address(const char *str, uint8_t *out_addr) { unsigned int i; uint8_t addr[6]; if (!str) return false; if (strlen(str) != 17) return false; for (i = 0; i < 15; i += 3) { if (!l_ascii_isxdigit(str[i])) return false; if (!l_ascii_isxdigit(str[i + 1])) return false; if (str[i + 2] != ':') return false; } if (!l_ascii_isxdigit(str[i])) return false; if (!l_ascii_isxdigit(str[i + 1])) return false; if (sscanf(str, "%2hhx:%2hhx:%2hhx:%2hhx:%2hhx:%2hhx", &addr[0], &addr[1], &addr[2], &addr[3], &addr[4], &addr[5]) != 6) return false; memcpy(out_addr, addr, sizeof(addr)); return true; } bool util_is_group_address(const uint8_t *addr) { /* 802.11-2016 section 9.2.2 */ return util_is_bit_set(addr[0], 0); } bool util_is_broadcast_address(const uint8_t *addr) { /* 802.11-2016 section 9.2.4.3 */ static const uint8_t bcast_addr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; return !memcmp(addr, bcast_addr, 6); } bool util_is_valid_sta_address(const uint8_t *addr) { return !util_is_broadcast_address(addr) && !util_is_group_address(addr); } /* This function assumes that identity is not bigger than 253 bytes */ const char *util_get_domain(const char *identity) { static char domain[256]; const char *c; memset(domain, 0, sizeof(domain)); for (c = identity; *c; c++) { switch (*c) { case '\\': memcpy(domain, identity, c - identity); return domain; case '@': l_strlcpy(domain, c + 1, sizeof(domain)); return domain; default: continue; } } return identity; } /* This function assumes that identity is not bigger than 253 bytes */ const char *util_get_username(const char *identity) { static char username[256]; const char *c; memset(username, 0, sizeof(username)); for (c = identity; *c; c++) { switch (*c) { case '\\': l_strlcpy(username, c + 1, sizeof(username)); return username; case '@': memcpy(username, identity, c - identity); return username; default: continue; } } return identity; } static bool is_prefix_valid(uint32_t ip, unsigned int prefix) { int i; for (i = 31 - prefix; i >= 0; i--) { if (ip & (1 << i)) return false; } return true; } /* * Parse a prefix notation IP string (e.g. A.B.C.D/E) into an IP range and * netmask. All returned IP addresses/mask will be in host order. The start/end * IP will only include the usable IP range where the last octet is not zero or * 255. */ bool util_ip_prefix_tohl(const char *ip, uint8_t *prefix_out, uint32_t *start_out, uint32_t *end_out, uint32_t *mask_out) { struct in_addr ia; int i; unsigned int prefix = 0; char no_prefix[INET_ADDRSTRLEN]; char *endp; uint32_t start_ip; uint32_t end_ip; uint32_t netmask = 0xffffffff; /* * Only iterate over the max length of an IP in case of invalid long * inputs. */ for (i = 0; i < INET_ADDRSTRLEN && ip[i] != '\0'; i++) { /* Found '/', check the next byte exists and parse prefix */ if (ip[i] == '/' && ip[i + 1] != '\0') { prefix = strtoul(ip + i + 1, &endp, 10); if (*endp != '\0') return false; break; } } if (prefix < 1 || prefix > 31) return false; /* 'i' will be at most INET_ADDRSTRLEN - 1 */ l_strlcpy(no_prefix, ip, i + 1); /* Check if IP preceeding prefix is valid */ if (inet_pton(AF_INET, no_prefix, &ia) != 1 || ia.s_addr == 0) return false; start_ip = ntohl(ia.s_addr); if (!is_prefix_valid(start_ip, prefix)) return false; /* Usable range is start + 1 .. end - 1 */ start_ip += 1; /* Calculate end IP and netmask */ end_ip = start_ip; for (i = 31 - prefix; i >= 0; i--) { end_ip |= (1 << i); netmask &= ~(1 << i); } end_ip -= 1; if (prefix_out) *prefix_out = prefix; if (start_out) *start_out = start_ip; if (end_out) *end_out = end_ip; if (mask_out) *mask_out = netmask; return true; }