diff options
Diffstat (limited to 'plugins/ipcrypt/ipcrypt.c')
| -rw-r--r-- | plugins/ipcrypt/ipcrypt.c | 66 |
1 files changed, 61 insertions, 5 deletions
diff --git a/plugins/ipcrypt/ipcrypt.c b/plugins/ipcrypt/ipcrypt.c index f8908a6..e9a1f58 100644 --- a/plugins/ipcrypt/ipcrypt.c +++ b/plugins/ipcrypt/ipcrypt.c @@ -42,13 +42,16 @@ #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> +#include <netinet/in.h> #include "dnscap_common.h" +#include "edns0_ecs.c" + static set_iaddr_t ipcrypt_set_iaddr = 0; static logerr_t* logerr; -static int only_clients = 0, only_servers = 0, dns_port = 53, iterations = 1, encrypt_v6 = 0, decrypt = 0; +static int only_clients = 0, only_servers = 0, dns_port = 53, iterations = 1, encrypt_v6 = 0, decrypt = 0, edns = 0; static uint8_t key[16]; /* @@ -157,7 +160,9 @@ void ipcrypt_usage() "\t-s Only en/de-crypt servers (port == 53)\n" "\t-p <port> Set port for -c/-s, default 53\n" "\t-i <num> Number of en/de-cryption iterations, default 1\n" - "\t-6 En/de-crypt IPv6 addresses, not default or recommended\n"); + "\t-6 En/de-crypt IPv6 addresses, not default or recommended\n" + "\t-e Also en/de-crypt EDNS(0) Client Subnet\n" + "\t-E ONLY en/de-crypt EDNS(0) Client Subnet, not IP addresses\n"); } void ipcrypt_extension(int ext, void* arg) @@ -175,7 +180,7 @@ void ipcrypt_getopt(int* argc, char** argv[]) unsigned long ul; char* p; - while ((c = getopt(*argc, *argv, "?k:f:Dcsp:i:6")) != EOF) { + while ((c = getopt(*argc, *argv, "?k:f:Dcsp:i:6eE")) != EOF) { switch (c) { case 'k': if (strlen(optarg) != 16) { @@ -226,6 +231,13 @@ void ipcrypt_getopt(int* argc, char** argv[]) case '6': encrypt_v6 = 1; break; + case 'e': + if (!edns) + edns = 1; + break; + case 'E': + edns = -1; + break; case '?': ipcrypt_usage(); if (!optopt || optopt == '?') { @@ -266,11 +278,55 @@ int ipcrypt_close(my_bpftimeval ts) return 0; } +void ecs_callback(int family, u_char* buf, size_t len) +{ + switch (family) { + case 1: // IPv4 + { + if (len > sizeof(struct in_addr)) + break; + struct in_addr in = { INADDR_ANY }; + memcpy(&in, buf, len); + decrypt ? _decrypt((uint8_t*)&in) : _encrypt((uint8_t*)&in); + memcpy(buf, &in, len); + break; + } + case 2: // IPv6 + if (len > sizeof(struct in6_addr)) + break; + if (encrypt_v6) { + struct in6_addr in = IN6ADDR_ANY_INIT; + memcpy(&in, buf, len); + if (decrypt) { + _decrypt((uint8_t*)&in); + _decrypt(((uint8_t*)&in) + 4); + _decrypt(((uint8_t*)&in) + 8); + _decrypt(((uint8_t*)&in) + 12); + } else { + _encrypt((uint8_t*)&in); + _encrypt(((uint8_t*)&in) + 4); + _encrypt(((uint8_t*)&in) + 8); + _encrypt(((uint8_t*)&in) + 12); + } + memcpy(buf, &in, len); + } + break; + default: + break; + } +} + int ipcrypt_filter(const char* descr, iaddr* from, iaddr* to, uint8_t proto, unsigned flags, unsigned sport, unsigned dport, my_bpftimeval ts, - const u_char* pkt_copy, const unsigned olen, - const u_char* payload, const unsigned payloadlen) + u_char* pkt_copy, const unsigned olen, + u_char* payload, const unsigned payloadlen) { + if (edns && flags & DNSCAP_OUTPUT_ISDNS && payload && payloadlen > DNS_MSG_HDR_SZ) { + parse_for_edns0_ecs(payload, payloadlen, ecs_callback); + if (edns < 0) + return 0; + } + for (;;) { if (only_clients && sport == dns_port) { if (sport != dport) { |