/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) Daniel Stenberg, , et al. * * This software is licensed as described in the file COPYING, which * you should have received as part of this distribution. The terms * are also available at https://curl.se/docs/copyright.html. * * You may opt to use, copy, modify, merge, publish, distribute and/or sell * copies of the Software, and permit persons to whom the Software is * furnished to do so, under the terms of the COPYING file. * * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * * SPDX-License-Identifier: curl * ***************************************************************************/ #include "curl_setup.h" #ifndef CURL_DISABLE_PROXY #include "inet_pton.h" #include "strcase.h" #include "noproxy.h" #ifdef HAVE_NETINET_IN_H #include #endif #ifdef HAVE_ARPA_INET_H #include #endif /* * Curl_cidr4_match() returns TRUE if the given IPv4 address is within the * specified CIDR address range. */ UNITTEST bool Curl_cidr4_match(const char *ipv4, /* 1.2.3.4 address */ const char *network, /* 1.2.3.4 address */ unsigned int bits) { unsigned int address = 0; unsigned int check = 0; if(bits > 32) /* strange input */ return FALSE; if(1 != Curl_inet_pton(AF_INET, ipv4, &address)) return FALSE; if(1 != Curl_inet_pton(AF_INET, network, &check)) return FALSE; if(bits && (bits != 32)) { unsigned int mask = 0xffffffff << (32 - bits); unsigned int haddr = htonl(address); unsigned int hcheck = htonl(check); #if 0 fprintf(stderr, "Host %s (%x) network %s (%x) bits %u mask %x => %x\n", ipv4, haddr, network, hcheck, bits, mask, (haddr ^ hcheck) & mask); #endif if((haddr ^ hcheck) & mask) return FALSE; return TRUE; } return (address == check); } UNITTEST bool Curl_cidr6_match(const char *ipv6, const char *network, unsigned int bits) { #ifdef USE_IPV6 unsigned int bytes; unsigned int rest; unsigned char address[16]; unsigned char check[16]; if(!bits) bits = 128; bytes = bits / 8; rest = bits & 0x07; if((bytes > 16) || ((bytes == 16) && rest)) return FALSE; if(1 != Curl_inet_pton(AF_INET6, ipv6, address)) return FALSE; if(1 != Curl_inet_pton(AF_INET6, network, check)) return FALSE; if(bytes && memcmp(address, check, bytes)) return FALSE; if(rest && !((address[bytes] ^ check[bytes]) & (0xff << (8 - rest)))) return FALSE; return TRUE; #else (void)ipv6; (void)network; (void)bits; return FALSE; #endif } enum nametype { TYPE_HOST, TYPE_IPV4, TYPE_IPV6 }; /**************************************************************** * Checks if the host is in the noproxy list. returns TRUE if it matches and * therefore the proxy should NOT be used. ****************************************************************/ bool Curl_check_noproxy(const char *name, const char *no_proxy) { char hostip[128]; /* * If we don't have a hostname at all, like for example with a FILE * transfer, we have nothing to interrogate the noproxy list with. */ if(!name || name[0] == '\0') return FALSE; /* no_proxy=domain1.dom,host.domain2.dom * (a comma-separated list of hosts which should * not be proxied, or an asterisk to override * all proxy variables) */ if(no_proxy && no_proxy[0]) { const char *p = no_proxy; size_t namelen; enum nametype type = TYPE_HOST; if(!strcmp("*", no_proxy)) return TRUE; /* NO_PROXY was specified and it wasn't just an asterisk */ if(name[0] == '[') { char *endptr; /* IPv6 numerical address */ endptr = strchr(name, ']'); if(!endptr) return FALSE; name++; namelen = endptr - name; if(namelen >= sizeof(hostip)) return FALSE; memcpy(hostip, name, namelen); hostip[namelen] = 0; name = hostip; type = TYPE_IPV6; } else { unsigned int address; namelen = strlen(name); if(1 == Curl_inet_pton(AF_INET, name, &address)) type = TYPE_IPV4; else { /* ignore trailing dots in the host name */ if(name[namelen - 1] == '.') namelen--; } } while(*p) { const char *token; size_t tokenlen = 0; bool match = FALSE; /* pass blanks */ while(*p && ISBLANK(*p)) p++; token = p; /* pass over the pattern */ while(*p && !ISBLANK(*p) && (*p != ',')) { p++; tokenlen++; } if(tokenlen) { switch(type) { case TYPE_HOST: /* ignore trailing dots in the token to check */ if(token[tokenlen - 1] == '.') tokenlen--; if(tokenlen && (*token == '.')) { /* ignore leading token dot as well */ token++; tokenlen--; } /* A: example.com matches 'example.com' B: www.example.com matches 'example.com' C: nonexample.com DOES NOT match 'example.com' */ if(tokenlen == namelen) /* case A, exact match */ match = strncasecompare(token, name, namelen); else if(tokenlen < namelen) { /* case B, tailmatch domain */ match = (name[namelen - tokenlen - 1] == '.') && strncasecompare(token, name + (namelen - tokenlen), tokenlen); } /* case C passes through, not a match */ break; case TYPE_IPV4: case TYPE_IPV6: { const char *check = token; char *slash; unsigned int bits = 0; char checkip[128]; if(tokenlen >= sizeof(checkip)) /* this cannot match */ break; /* copy the check name to a temp buffer */ memcpy(checkip, check, tokenlen); checkip[tokenlen] = 0; check = checkip; slash = strchr(check, '/'); /* if the slash is part of this token, use it */ if(slash) { /* if the bits variable gets a crazy value here, that is fine as the value will then be rejected in the cidr function */ bits = (unsigned int)atoi(slash + 1); *slash = 0; /* null terminate there */ } if(type == TYPE_IPV6) match = Curl_cidr6_match(name, check, bits); else match = Curl_cidr4_match(name, check, bits); break; } } if(match) return TRUE; } /* if(tokenlen) */ /* pass blanks after pattern */ while(ISBLANK(*p)) p++; /* if not a comma, this ends the loop */ if(*p != ',') break; /* pass any number of commas */ while(*p == ',') p++; } /* while(*p) */ } /* NO_PROXY was specified and it wasn't just an asterisk */ return FALSE; } #endif /* CURL_DISABLE_PROXY */