diff --git a/ReadMe.md b/ReadMe.md
index 44bb1f7..61e5a41 100755
--- a/ReadMe.md
+++ b/ReadMe.md
@@ -446,9 +446,9 @@ Note: Merlin firmware is derived from ASUS firmware and can theoretically be use
|audit-size|audit log size|128K|number+K,M,G|audit-size 128K
|audit-num|archived audit log number|2|Integer|audit-num 2
|conf-file|additional conf file|None|File path|conf-file /etc/smartdns/smartdns.more.conf
-|server|Upstream UDP DNS server|None|Repeatable
[ip][:port]: Server IP, port optional.
[-blacklist-ip]: The `-blacklist-ip` parameter is to filtering IPs which is configured by `blacklist-ip`.
[-check-edns]: edns filter.
[-group [group] ...]: The group to which the DNS server belongs, such as office, foreign, use with nameserver.
[-exclude-default-group]: Exclude DNS servers from the default group| server 8.8.8.8:53 -blacklist-ip -check-edns
-|server-tcp|Upstream TCP DNS server|None|Repeatable
[ip][:port]: Server IP, port optional.
[-blacklist-ip]: The `-blacklist-ip` parameter is to filtering IPs which is configured by `blacklist-ip`.
[-group [group] ...]: The group to which the DNS server belongs, such as office, foreign, use with nameserver.
[-exclude-default-group]: Exclude DNS servers from the default group| server-tcp 8.8.8.8:53
-|server-tls|Upstream TLS DNS server|None|Repeatable
[ip][:port]: Server IP, port optional.
[-blacklist-ip]: The `-blacklist-ip` parameter is to filtering IPs which is configured by `blacklist-ip`.
[-group [group] ...]: The group to which the DNS server belongs, such as office, foreign, use with nameserver.
[-exclude-default-group]: Exclude DNS servers from the default group| server-tls 8.8.8.8:853
+|server|Upstream UDP DNS server|None|Repeatable
`[ip][:port]`: Server IP, port optional.
`[-blacklist-ip]`: The "-blacklist-ip" parameter is to filtering IPs which is configured by "blacklist-ip".
`[-check-edns]`: edns filter.
`[-group [group] ...]`: The group to which the DNS server belongs, such as office, foreign, use with nameserver.
`[-exclude-default-group]`: Exclude DNS servers from the default group| server 8.8.8.8:53 -blacklist-ip -check-edns
+|server-tcp|Upstream TCP DNS server|None|Repeatable
`[ip][:port]`: Server IP, port optional.
`[-blacklist-ip]`: The "-blacklist-ip" parameter is to filtering IPs which is configured by "blacklist-ip".
`[-group [group] ...]`: The group to which the DNS server belongs, such as office, foreign, use with nameserver.
`[-exclude-default-group]`: Exclude DNS servers from the default group| server-tcp 8.8.8.8:53
+|server-tls|Upstream TLS DNS server|None|Repeatable
`[ip][:port]`: Server IP, port optional.
`[-spki-pin [sha256-pin]]`: TLS verify SPKI value, a base64 encoded SHA256 hash
`[-blacklist-ip]`: The "-blacklist-ip" parameter is to filtering IPs which is configured by "blacklist-ip".
`[-group [group] ...]`: The group to which the DNS server belongs, such as office, foreign, use with nameserver.
`[-exclude-default-group]`: Exclude DNS servers from the default group| server-tls 8.8.8.8:853
|address|Domain IP address|None|address /domain/[ip\|-\|-4\|-6\|#\|#4\|#6], `-` for ignore, `#` for return SOA, `4` for IPV4, `6` for IPV6| address /www.example.com/1.2.3.4
|nameserver|To query domain with specific server group|None|nameserver /domain/[group\|-], `group` is the group name, `-` means ignore this rule, use the `-group` parameter in the related server|nameserver /www.example.com/office
|ipset|Domain IPSet|None|ipset /domain/[ipset\|-], `-` for ignore|ipset /www.example.com/pass
diff --git a/ReadMe_zh-CN.md b/ReadMe_zh-CN.md
index c690228..458b946 100644
--- a/ReadMe_zh-CN.md
+++ b/ReadMe_zh-CN.md
@@ -447,9 +447,9 @@ rtt min/avg/max/mdev = 5.954/6.133/6.313/0.195 ms
|audit-size|审计大小|128K|数字+K,M,G|audit-size 128K
|audit-num|审计归档个数|2|数字|audit-num 2
|conf-file|附加配置文件|无|文件路径|conf-file /etc/smartdns/smartdns.more.conf
-|server|上游UDP DNS|无|可重复
[ip][:port]：服务器IP，端口可选。
[-blacklist-ip]：blacklist-ip参数指定使用blacklist-ip配置IP过滤结果。
[-check-edns]：edns过滤。
[-group [group] ...]：DNS服务器所属组，比如office, foreign，和nameserver配套使用。
[-exclude-default-group]：将DNS服务器从默认组中排除| server 8.8.8.8:53 -blacklist-ip -check-edns -group g1
-|server-tcp|上游TCP DNS|无|可重复
[ip][:port]：服务器IP，端口可选。
[-blacklist-ip]：blacklist-ip参数指定使用blacklist-ip配置IP过滤结果。
[-group [group] ...]：DNS服务器所属组，比如office, foreign，和nameserver配套使用。
[-exclude-default-group]：将DNS服务器从默认组中排除| server-tcp 8.8.8.8:53
-|server-tls|上游TLS DNS|无|可重复
[ip][:port]：服务器IP，端口可选。
[-blacklist-ip]：blacklist-ip参数指定使用blacklist-ip配置IP过滤结果。
[-group [group] ...]：DNS服务器所属组，比如office, foreign，和nameserver配套使用。
[-exclude-default-group]：将DNS服务器从默认组中排除| server-tls 8.8.8.8:853
+|server|上游UDP DNS|无|可重复
`[ip][:port]`：服务器IP，端口可选。
`[-blacklist-ip]`：blacklist-ip参数指定使用blacklist-ip配置IP过滤结果。
`[-check-edns]`：edns过滤。
`[-group [group] ...]`：DNS服务器所属组，比如office, foreign，和nameserver配套使用。
`[-exclude-default-group]`：将DNS服务器从默认组中排除| server 8.8.8.8:53 -blacklist-ip -check-edns -group g1
+|server-tcp|上游TCP DNS|无|可重复
`[ip][:port]`：服务器IP，端口可选。
`[-blacklist-ip]`：blacklist-ip参数指定使用blacklist-ip配置IP过滤结果。
`[-group [group] ...]`：DNS服务器所属组，比如office, foreign，和nameserver配套使用。
`[-exclude-default-group]`：将DNS服务器从默认组中排除| server-tcp 8.8.8.8:53
+|server-tls|上游TLS DNS|无|可重复
`[ip][:port]`：服务器IP，端口可选。
`[-spki-pin [sha256-pin]]`: TLS合法性校验SPKI值，base64编码的sha256 SPKI pin值
`[-blacklist-ip]`：blacklist-ip参数指定使用blacklist-ip配置IP过滤结果。
`[-group [group] ...]`：DNS服务器所属组，比如office, foreign，和nameserver配套使用。
`[-exclude-default-group]`：将DNS服务器从默认组中排除| server-tls 8.8.8.8:853
|address|指定域名IP地址|无|address /domain/[ip\|-\|-4\|-6\|#\|#4\|#6]
`-`表示忽略
`#`表示返回SOA
`4`表示IPV4
`6`表示IPV6| address /www.example.com/1.2.3.4
|nameserver|指定域名使用server组解析|无|nameserver /domain/[group\|-], `group`为组名，`-`表示忽略此规则，配套server中的`-group`参数使用| nameserver /www.example.com/office
|ipset|域名IPSET|None|ipset /domain/[ipset\|-], `-`表示忽略|ipset /www.example.com/pass
diff --git a/etc/smartdns/smartdns.conf b/etc/smartdns/smartdns.conf
index bc2a1cf..9b3e29c 100644
--- a/etc/smartdns/smartdns.conf
+++ b/etc/smartdns/smartdns.conf
@@ -93,7 +93,10 @@ log-level info
# server-tcp 8.8.8.8
# remote tls dns server list
-# server-tls [IP]:[PORT] [-blacklist-ip] [-group [group] ...] [-exclude-default-group]
+# server-tls [IP]:[PORT] [-blacklist-ip] [-spki-pin [sha256-pin]] [-group [group] ...] [-exclude-default-group]
+# -spki-pin: TLS spki pin to verify.
+# Get SKPI with this command:
+# echo | openssl s_client -connect '[ip]:853' | openssl x509 -pubkey -noout | openssl pkey -pubin -outform der | openssl dgst -sha256 -binary | openssl enc -base64
# default port is 853
# server-tls 8.8.8.8
# server-tls 1.0.0.1
@@ -115,4 +118,4 @@ log-level info
# specific ipset to domain
# ipset /domain/[ipset|-]
# ipset /www.example.com/block, set ipset with ipset name of block
-# ipset /www.example.com/-, ignore this domain
\ No newline at end of file
+# ipset /www.example.com/-, ignore this domain
diff --git a/src/dns_client.c b/src/dns_client.c
index 502a6f1..13bb404 100644
--- a/src/dns_client.c
+++ b/src/dns_client.c
@@ -93,6 +93,9 @@ struct dns_server_info {
/* server type */
dns_server_type_t type;
+ unsigned char *spki;
+ int spki_len;
+
/* client socket */
int fd;
int ttl;
@@ -535,9 +538,25 @@ void _dns_client_group_remove_all(void)
}
/* add dns server information */
-int _dns_client_server_add(char *server_ip, struct addrinfo *gai, dns_server_type_t server_type, unsigned int server_flag, unsigned int result_flag, int ttl)
+int _dns_client_server_add(char *server_ip, struct addrinfo *gai, dns_server_type_t server_type, unsigned int server_flag, unsigned int result_flag, int ttl, char *spki)
{
struct dns_server_info *server_info = NULL;
+ unsigned char *spki_data = NULL;
+ int spki_data_len = 0;
+
+ /* read SPKI */
+ if (spki && (strlen(spki) < DNS_MAX_SPKI_LEN)) {
+ spki_data = malloc(DNS_MAX_SPKI_LEN);
+ if (spki_data) {
+ memset(spki_data, 0, DNS_MAX_SPKI_LEN);
+ spki_data_len = SSL_base64_decode(spki, spki_data);
+ if (spki_data_len != SHA256_DIGEST_LENGTH) {
+ free(spki_data);
+ spki_data = NULL;
+ spki_data_len = 0;
+ }
+ }
+ }
if (_dns_client_server_exist(gai, server_type) == 0) {
return 0;
@@ -562,6 +581,8 @@ int _dns_client_server_add(char *server_ip, struct addrinfo *gai, dns_server_typ
server_info->result_flag = result_flag;
server_info->ttl = ttl;
server_info->ttl_range = 0;
+ server_info->spki = spki_data;
+ server_info->spki_len = spki_data_len;
if ((server_flag & SERVER_FLAG_EXCLUDE_DEFAULT) == 0) {
if (_dns_client_add_to_group(DNS_SERVER_GROUP_DEFAULT, server_info) != 0) {
@@ -605,6 +626,10 @@ int _dns_client_server_add(char *server_ip, struct addrinfo *gai, dns_server_typ
atomic_inc(&client.dns_server_num);
return 0;
errout:
+ if (spki_data) {
+ free(spki_data);
+ }
+
if (server_info) {
if (server_info->ssl_ctx) {
SSL_CTX_free(server_info->ssl_ctx);
@@ -673,6 +698,10 @@ void _dns_client_server_remove_all(void)
{
list_del(&server_info->list);
_dns_client_server_close(server_info);
+ if (server_info->spki) {
+ free(server_info->spki);
+ server_info->spki = NULL;
+ }
free(server_info);
}
pthread_mutex_unlock(&client.server_list_lock);
@@ -707,7 +736,7 @@ int _dns_client_server_remove(char *server_ip, struct addrinfo *gai, dns_server_
return -1;
}
-int _dns_client_server_operate(char *server_ip, int port, dns_server_type_t server_type, unsigned int server_flag, unsigned int result_flag, int ttl, int operate)
+int _dns_client_server_operate(char *server_ip, int port, dns_server_type_t server_type, unsigned int server_flag, unsigned int result_flag, int ttl, char *spki, int operate)
{
char port_s[8];
int sock_type;
@@ -741,7 +770,7 @@ int _dns_client_server_operate(char *server_ip, int port, dns_server_type_t serv
}
if (operate == 0) {
- ret = _dns_client_server_add(server_ip, gai, server_type, server_flag, result_flag, ttl);
+ ret = _dns_client_server_add(server_ip, gai, server_type, server_flag, result_flag, ttl, spki);
if (ret != 0) {
goto errout;
}
@@ -760,14 +789,14 @@ errout:
return -1;
}
-int dns_client_add_server(char *server_ip, int port, dns_server_type_t server_type, unsigned server_flag, unsigned int result_flag, int ttl)
+int dns_client_add_server(char *server_ip, int port, dns_server_type_t server_type, unsigned server_flag, unsigned int result_flag, int ttl, char *spki)
{
- return _dns_client_server_operate(server_ip, port, server_type, server_flag, result_flag, ttl, 0);
+ return _dns_client_server_operate(server_ip, port, server_type, server_flag, result_flag, ttl, spki, 0);
}
int dns_client_remove_server(char *server_ip, int port, dns_server_type_t server_type)
{
- return _dns_client_server_operate(server_ip, port, server_type, 0, 0, 0, 1);
+ return _dns_client_server_operate(server_ip, port, server_type, 0, 0, 0, NULL, 1);
}
int dns_server_num(void)
@@ -1653,11 +1682,12 @@ static int _dns_client_tls_verify(struct dns_server_info *server_info)
{
X509 *cert = NULL;
char peer_CN[256];
- const EVP_MD *digest;
- unsigned char md[EVP_MAX_MD_SIZE];
- unsigned int n;
char cert_fingerprint[256];
int i = 0;
+ int key_len = 0;
+ unsigned char *key_data = NULL;
+ unsigned char *key_data_tmp = NULL;
+ unsigned char *key_sha256 = NULL;
cert = SSL_get_peer_certificate(server_info->ssl);
if (cert == NULL) {
@@ -1666,28 +1696,66 @@ static int _dns_client_tls_verify(struct dns_server_info *server_info)
}
X509_NAME_get_text_by_NID(X509_get_subject_name(cert), NID_commonName, peer_CN, 256);
-
tlog(TLOG_DEBUG, "peer CN: %s", peer_CN);
- digest = EVP_get_digestbyname("sha256");
- X509_digest(cert, digest, md, &n);
+ /* get spki pin */
+ key_len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), NULL);
+ if (key_len <= 0 ) {
+ tlog(TLOG_ERROR, "get x509 public key failed.");
+ goto errout;
+ }
+
+ key_data = OPENSSL_malloc(key_len);
+ key_data_tmp = key_data;
+ if (key_data == NULL) {
+ tlog(TLOG_ERROR, "malloc memory failed.");
+ goto errout;
+ }
+
+ i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert), &key_data_tmp);
+
+ key_sha256 = SSL_SHA256(key_data, key_len, 0);
+ if (key_sha256 == NULL) {
+ tlog(TLOG_ERROR, "get sha256 failed.");
+ goto errout;
+ }
char *ptr = cert_fingerprint;
- for (i = 0; i < 32; i++) {
- *ptr = _dns_client_to_hex(md[i] >> 4 & 0xF);
+ for (i = 0; i < SHA256_DIGEST_LENGTH; i++) {
+ *ptr = _dns_client_to_hex(key_sha256[i] >> 4 & 0xF);
ptr++;
- *ptr = _dns_client_to_hex(md[i] & 0xF);
+ *ptr = _dns_client_to_hex(key_sha256[i] & 0xF);
ptr++;
*ptr = ':';
ptr++;
}
ptr--;
*ptr = 0;
- tlog(TLOG_DEBUG, "cert fingerprint(%s): %s", "sha256", cert_fingerprint);
+ tlog(TLOG_DEBUG, "cert SPKI pin(%s): %s", "sha256", cert_fingerprint);
+ if (server_info->spki) {
+ if (memcmp(server_info->spki, key_sha256, server_info->spki_len) != 0) {
+ tlog(TLOG_INFO, "server %s cert spki is invalid", server_info->ip);
+ goto errout;
+ } else {
+ tlog(TLOG_DEBUG, "server %s cert spki verify succeed", server_info->ip);
+ }
+ }
+
+ OPENSSL_free(key_data);
X509_free(cert);
-
return 0;
+
+errout:
+ if (key_data) {
+ OPENSSL_free(key_data);
+ }
+
+ if (cert) {
+ X509_free(cert);
+ }
+
+ return -1;
}
static int _dns_client_process_tls(struct dns_server_info *server_info, struct epoll_event *event, unsigned long now)
diff --git a/src/dns_client.h b/src/dns_client.h
index 774cea4..3f65090 100644
--- a/src/dns_client.h
+++ b/src/dns_client.h
@@ -36,7 +36,7 @@ int dns_client_query(char *domain, int qtype, dns_client_callback callback, void
void dns_client_exit(void);
/* add remote dns server */
-int dns_client_add_server(char *server_ip, int port, dns_server_type_t server_type, unsigned int server_flag, unsigned int result_flag, int ttl);
+int dns_client_add_server(char *server_ip, int port, dns_server_type_t server_type, unsigned int server_flag, unsigned int result_flag, int ttl, char *spki);
/* remove remote dns server */
int dns_client_remove_server(char *server_ip, int port, dns_server_type_t server_type);
diff --git a/src/dns_conf.c b/src/dns_conf.c
index d3ae495..134f822 100644
--- a/src/dns_conf.c
+++ b/src/dns_conf.c
@@ -142,11 +142,14 @@ int config_server(int argc, char *argv[], dns_server_type_t type, int default_po
int opt = 0;
unsigned int result_flag = 0;
unsigned int server_flag = 0;
+ unsigned char *spki = NULL;
+
int ttl = 0;
/* clang-format off */
static struct option long_options[] = {
{"blacklist-ip", 0, 0, 'b'},
{"check-edns", 0, 0, 'e'},
+ {"spki-pin", required_argument, 0, 'p'},
{"check-ttl", required_argument, 0, 't'},
{"group", required_argument, 0, 'g'},
{"exclude-default-group", 0, 0, 'E'},
@@ -164,6 +167,7 @@ int config_server(int argc, char *argv[], dns_server_type_t type, int default_po
}
server = &dns_conf_servers[index];
+ server->spki[0] = '\0';
ip = argv[1];
/* parse ip, port from ip */
@@ -200,7 +204,7 @@ int config_server(int argc, char *argv[], dns_server_type_t type, int default_po
ttl = atoi(optarg);
if (ttl < -255 || ttl > 255) {
tlog(TLOG_ERROR, "ttl value is invalid.");
- return -1;
+ goto errout;
}
result_flag |= DNSSERVER_FLAG_CHECK_TTL;
break;
@@ -212,10 +216,14 @@ int config_server(int argc, char *argv[], dns_server_type_t type, int default_po
case 'g': {
if (dns_conf_get_group_set(optarg, server) != 0) {
tlog(TLOG_ERROR, "add group failed.");
- return -1;
+ goto errout;
}
break;
}
+ case 'p': {
+ strncpy(server->spki, optarg, DNS_MAX_SPKI_LEN);
+ break;
+ }
default:
break;
}
@@ -230,6 +238,13 @@ int config_server(int argc, char *argv[], dns_server_type_t type, int default_po
tlog(TLOG_DEBUG, "add server %s, flag: %X, ttl: %d", ip, result_flag, ttl);
return 0;
+
+errout:
+ if (spki) {
+ free(spki);
+ }
+
+ return -1;
}
int config_domain_iter_cb(void *data, const unsigned char *key, uint32_t key_len, void *value)
diff --git a/src/dns_conf.h b/src/dns_conf.h
index 588ffaa..4d17e85 100644
--- a/src/dns_conf.h
+++ b/src/dns_conf.h
@@ -15,6 +15,7 @@
#define DNS_GROUP_NAME_LEN 32
#define DNS_NAX_GROUP_NUMBER 16
#define DNS_MAX_IPLEN 64
+#define DNS_MAX_SPKI_LEN 64
#define DNS_MAX_PATH 1024
#define DEFAULT_DNS_PORT 53
#define DEFAULT_DNS_TLS_PORT 853
@@ -91,6 +92,7 @@ struct dns_servers {
unsigned int server_flag;
int ttl;
dns_server_type_t type;
+ char spki[DNS_MAX_SPKI_LEN];
};
/* ip address lists of domain */
diff --git a/src/smartdns.c b/src/smartdns.c
index 3366cba..ba9d94c 100644
--- a/src/smartdns.c
+++ b/src/smartdns.c
@@ -130,7 +130,7 @@ int smartdns_add_servers(void)
for (i = 0; i < dns_conf_server_num; i++) {
ret = dns_client_add_server(dns_conf_servers[i].server, dns_conf_servers[i].port, dns_conf_servers[i].type, dns_conf_servers[i].server_flag, dns_conf_servers[i].result_flag,
- dns_conf_servers[i].ttl);
+ dns_conf_servers[i].ttl, dns_conf_servers[i].spki);
if (ret != 0) {
tlog(TLOG_ERROR, "add server failed, %s:%d", dns_conf_servers[i].server, dns_conf_servers[i].port);
return -1;
diff --git a/src/util.c b/src/util.c
index a9183a5..b4def9b 100644
--- a/src/util.c
+++ b/src/util.c
@@ -353,6 +353,44 @@ int ipset_del(const char *ipsetname, const unsigned char addr[], int addr_len)
return _ipset_operate(ipsetname, addr, addr_len, 0, IPSET_DEL);
}
+unsigned char *SSL_SHA256(const unsigned char *d, size_t n, unsigned char *md)
+{
+ SHA256_CTX c;
+ static unsigned char m[SHA256_DIGEST_LENGTH];
+
+ if (md == NULL)
+ md = m;
+ SHA256_Init(&c);
+ SHA256_Update(&c, d, n);
+ SHA256_Final(md, &c);
+ OPENSSL_cleanse(&c, sizeof(c));
+ return (md);
+}
+
+int SSL_base64_decode(const char *in, unsigned char *out)
+{
+ size_t inlen = strlen(in);
+ int outlen;
+
+ if (inlen == 0) {
+ return 0;
+ }
+
+ outlen = EVP_DecodeBlock(out, (unsigned char *)in, inlen);
+ if (outlen < 0) {
+ goto errout;
+ }
+
+ /* Subtract padding bytes from |outlen| */
+ while (in[--inlen] == '=') {
+ --outlen;
+ }
+
+ return outlen;
+errout:
+ return -1;
+}
+
#define THREAD_STACK_SIZE (16*1024)
static pthread_mutex_t *lock_cs;
static long *lock_count;
diff --git a/src/util.h b/src/util.h
index 9d1bee7..76d5893 100644
--- a/src/util.h
+++ b/src/util.h
@@ -30,4 +30,8 @@ void SSL_CRYPTO_thread_setup(void);
void SSL_CRYPTO_thread_cleanup(void);
+unsigned char *SSL_SHA256(const unsigned char *d, size_t n, unsigned char *md);
+
+int SSL_base64_decode(const char *in, unsigned char *out);
+
#endif
\ No newline at end of file