src/ssl_utils.c - haproxy - Gitiles

 /*
  * Utility functions for SSL:
  * Mostly generic functions that retrieve information from certificates
  *
  * Copyright (C) 2012 EXCELIANCE, Emeric Brun <ebrun@exceliance.fr>
  * Copyright (C) 2020 HAProxy Technologies, William Lallemand <wlallemand@haproxy.com>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  */


 #include <haproxy/api.h>
 #include <haproxy/buf-t.h>
 #include <haproxy/chunk.h>
 #include <haproxy/openssl-compat.h>
 #include <haproxy/ssl_sock.h>
 #include <haproxy/ssl_utils.h>

 /* fill a buffer with the algorithm and size of a public key */
 int cert_get_pkey_algo(X509 *crt, struct buffer *out)
 {
 	int bits = 0;
 	int sig = TLSEXT_signature_anonymous;
 	int len = -1;
 	EVP_PKEY *pkey;

 	pkey = X509_get_pubkey(crt);
 	if (pkey) {
 		bits = EVP_PKEY_bits(pkey);
 		switch(EVP_PKEY_base_id(pkey)) {
 		case EVP_PKEY_RSA:
 			sig = TLSEXT_signature_rsa;
 			break;
 		case EVP_PKEY_EC:
 			sig = TLSEXT_signature_ecdsa;
 			break;
 		case EVP_PKEY_DSA:
 			sig = TLSEXT_signature_dsa;
 			break;
 		}
 		EVP_PKEY_free(pkey);
 	}

 	switch(sig) {
 	case TLSEXT_signature_rsa:
 		len = chunk_printf(out, "RSA%d", bits);
 		break;
 	case TLSEXT_signature_ecdsa:
 		len = chunk_printf(out, "EC%d", bits);
 		break;
 	case TLSEXT_signature_dsa:
 		len = chunk_printf(out, "DSA%d", bits);
 		break;
 	default:
 		return 0;
 	}
 	if (len < 0)
 		return 0;
 	return 1;
 }

 /* Extract a serial from a cert, and copy it to a chunk.
  * Returns 1 if serial is found and copied, 0 if no serial found and
  * -1 if output is not large enough.
  */
 int ssl_sock_get_serial(X509 *crt, struct buffer *out)
 {
 	ASN1_INTEGER *serial;

 	serial = X509_get_serialNumber(crt);
 	if (!serial)
 		return 0;

 	if (out->size < serial->length)
 		return -1;

 	memcpy(out->area, serial->data, serial->length);
 	out->data = serial->length;
 	return 1;
 }

 /* Extract a cert to der, and copy it to a chunk.
  * Returns 1 if the cert is found and copied, 0 on der conversion failure
  * and -1 if the output is not large enough.
  */
 int ssl_sock_crt2der(X509 *crt, struct buffer *out)
 {
 	int len;
 	unsigned char *p = (unsigned char *) out->area;

 	len = i2d_X509(crt, NULL);
 	if (len <= 0)
 		return 1;

 	if (out->size < len)
 		return -1;

 	i2d_X509(crt, &p);
 	out->data = len;
 	return 1;
 }


 /* Copy Date in ASN1_UTCTIME format in struct buffer out.
  * Returns 1 if serial is found and copied, 0 if no valid time found
  * and -1 if output is not large enough.
  */
 int ssl_sock_get_time(ASN1_TIME *tm, struct buffer *out)
 {
 	if (tm->type == V_ASN1_GENERALIZEDTIME) {
 		ASN1_GENERALIZEDTIME *gentm = (ASN1_GENERALIZEDTIME *)tm;

 		if (gentm->length < 12)
 			return 0;
 		if (gentm->data[0] != 0x32 || gentm->data[1] != 0x30)
 			return 0;
 		if (out->size < gentm->length-2)
 			return -1;

 		memcpy(out->area, gentm->data+2, gentm->length-2);
 		out->data = gentm->length-2;
 		return 1;
 	}
 	else if (tm->type == V_ASN1_UTCTIME) {
 		ASN1_UTCTIME *utctm = (ASN1_UTCTIME *)tm;

 		if (utctm->length < 10)
 			return 0;
 		if (utctm->data[0] >= 0x35)
 			return 0;
 		if (out->size < utctm->length)
 			return -1;

 		memcpy(out->area, utctm->data, utctm->length);
 		out->data = utctm->length;
 		return 1;
 	}

 	return 0;
 }

 /* Extract an entry from a X509_NAME and copy its value to an output chunk.
  * Returns 1 if entry found, 0 if entry not found, or -1 if output not large enough.
  */
 int ssl_sock_get_dn_entry(X509_NAME *a, const struct buffer *entry, int pos,
                           struct buffer *out)
 {
 	X509_NAME_ENTRY *ne;
 	ASN1_OBJECT *obj;
 	ASN1_STRING *data;
 	const unsigned char *data_ptr;
 	int data_len;
 	int i, j, n;
 	int cur = 0;
 	const char *s;
 	char tmp[128];
 	int name_count;

 	name_count = X509_NAME_entry_count(a);

 	out->data = 0;
 	for (i = 0; i < name_count; i++) {
 		if (pos < 0)
 			j = (name_count-1) - i;
 		else
 			j = i;

 		ne = X509_NAME_get_entry(a, j);
 		obj = X509_NAME_ENTRY_get_object(ne);
 		data = X509_NAME_ENTRY_get_data(ne);
 		data_ptr = ASN1_STRING_get0_data(data);
 		data_len = ASN1_STRING_length(data);
 		n = OBJ_obj2nid(obj);
 		if ((n == NID_undef) || ((s = OBJ_nid2sn(n)) == NULL)) {
 			i2t_ASN1_OBJECT(tmp, sizeof(tmp), obj);
 			s = tmp;
 		}

 		if (chunk_strcasecmp(entry, s) != 0)
 			continue;

 		if (pos < 0)
 			cur--;
 		else
 			cur++;

 		if (cur != pos)
 			continue;

 		if (data_len > out->size)
 			return -1;

 		memcpy(out->area, data_ptr, data_len);
 		out->data = data_len;
 		return 1;
 	}

 	return 0;

 }

 /*
  * Extract the DN in the specified format from the X509_NAME and copy result to a chunk.
  * Currently supports rfc2253 for returning LDAP V3 DNs.
  * Returns 1 if dn entries exist, 0 if no dn entry was found.
  */
 int ssl_sock_get_dn_formatted(X509_NAME *a, const struct buffer *format, struct buffer *out)
 {
 	BIO *bio = NULL;
 	int ret = 0;
 	int data_len = 0;

 	if (chunk_strcmp(format, "rfc2253") == 0) {
 		bio = BIO_new(BIO_s_mem());
 		if (bio == NULL)
 			goto out;

 		if (X509_NAME_print_ex(bio, a, 0, XN_FLAG_RFC2253) < 0)
 			goto out;

 		if ((data_len = BIO_read(bio, out->area, out->size)) <= 0)
 			goto out;

 		out->data = data_len;

 		ret = 1;
 	}
 out:
 	if (bio)
 		BIO_free(bio);
 	return ret;
 }

 /* Extract and format full DN from a X509_NAME and copy result into a chunk
  * Returns 1 if dn entries exits, 0 if no dn entry found or -1 if output is not large enough.
  */
 int ssl_sock_get_dn_oneline(X509_NAME *a, struct buffer *out)
 {
 	X509_NAME_ENTRY *ne;
 	ASN1_OBJECT *obj;
 	ASN1_STRING *data;
 	const unsigned char *data_ptr;
 	int data_len;
 	int i, n, ln;
 	int l = 0;
 	const char *s;
 	char *p;
 	char tmp[128];
 	int name_count;


 	name_count = X509_NAME_entry_count(a);

 	out->data = 0;
 	p = out->area;
 	for (i = 0; i < name_count; i++) {
 		ne = X509_NAME_get_entry(a, i);
 		obj = X509_NAME_ENTRY_get_object(ne);
 		data = X509_NAME_ENTRY_get_data(ne);
 		data_ptr = ASN1_STRING_get0_data(data);
 		data_len = ASN1_STRING_length(data);
 		n = OBJ_obj2nid(obj);
 		if ((n == NID_undef) || ((s = OBJ_nid2sn(n)) == NULL)) {
 			i2t_ASN1_OBJECT(tmp, sizeof(tmp), obj);
 			s = tmp;
 		}
 		ln = strlen(s);

 		l += 1 + ln + 1 + data_len;
 		if (l > out->size)
 			return -1;
 		out->data = l;

 		*(p++)='/';
 		memcpy(p, s, ln);
 		p += ln;
 		*(p++)='=';
 		memcpy(p, data_ptr, data_len);
 		p += data_len;
 	}

 	if (!out->data)
 		return 0;

 	return 1;
 }


 extern int ssl_client_crt_ref_index;

 /*
  * This function fetches the SSL certificate for a specific connection (either
  * client certificate or server certificate depending on the cert_peer
  * parameter).
  * When trying to get the peer certificate from the server side, we first try to
  * use the dedicated SSL_get_peer_certificate function, but we fall back to
  * trying to get the client certificate reference that might have been stored in
  * the SSL structure's ex_data during the verification process.
  * Returns NULL in case of failure.
  */
 X509* ssl_sock_get_peer_certificate(SSL *ssl)
 {
 	X509* cert;

 	cert = SSL_get_peer_certificate(ssl);
 	/* Get the client certificate reference stored in the SSL
 	 * structure's ex_data during the verification process. */
 	if (!cert) {
 		cert = SSL_get_ex_data(ssl, ssl_client_crt_ref_index);
 		if (cert)
 			X509_up_ref(cert);
 	}

 	return cert;
 }

 /*
  * Take an OpenSSL version in text format and return a numeric openssl version
  * Return 0 if it failed to parse the version
  *
  *  https://www.openssl.org/docs/man1.1.1/man3/OPENSSL_VERSION_NUMBER.html
  *
  *  MNNFFPPS: major minor fix patch status
  *
  *  The status nibble has one of the values 0 for development, 1 to e for betas
  *  1 to 14, and f for release.
  *
  *  for example
  *
  *   0x0090821f     0.9.8zh
  *   0x1000215f     1.0.2u
  *   0x30000000     3.0.0-alpha17
  *   0x30000002     3.0.0-beta2
  *   0x3000000e     3.0.0-beta14
  *   0x3000000f     3.0.0
  */
 unsigned int openssl_version_parser(const char *version)
 {
 	unsigned int numversion;
 	unsigned int major = 0, minor = 0, fix = 0, patch = 0, status = 0;
 	char *p, *end;

 	p = (char *)version;

 	if (!p || !*p)
 		return 0;

 	major = strtol(p, &end, 10);
 	if (*end != '.' || major > 0xf)
 		goto error;
 	p = end + 1;

 	minor = strtol(p, &end, 10);
 	if (*end != '.' || minor > 0xff)
 		goto error;
 	p = end + 1;

 	fix = strtol(p, &end, 10);
 	if (fix > 0xff)
 		goto error;
 	p = end;

 	if (!*p) {
 		/* end of the string, that's a release */
 		status = 0xf;
 	} else if (*p == '-') {
 		/* after the hyphen, only the beta will increment the status
 		 * counter, all others versions will be considered as "dev" and
 		 * does not increment anything */
 		p++;

 		if (!strncmp(p, "beta", 4)) {
 			p += 4;
 			status = strtol(p, &end, 10);
 			if (status > 14)
 				goto error;
 		}
 	} else {
 		/* that's a patch release */
 		patch = 1;

 		/* add the value of each letter */
 		while (*p) {
 			patch += (*p & ~0x20) - 'A';
 			p++;
 		}
 		status = 0xf;
 	}

 end:
 	numversion =  ((major & 0xf) << 28) | ((minor & 0xff) << 20) | ((fix & 0xff) << 12) | ((patch & 0xff) << 4) | (status & 0xf);
 	return numversion;

 error:
 	return 0;

 }

 /* Exclude GREASE (RFC8701) values from input buffer */
 void exclude_tls_grease(char *input, int len, struct buffer *output)
 {
 	int ptr = 0;

 	while (ptr < len - 1) {
 		if (input[ptr] != input[ptr+1] || (input[ptr] & 0x0f) != 0x0a) {
 			if (output->data <= output->size - 2) {
 				memcpy(output->area + output->data, input + ptr, 2);
 				output->data += 2;
 			} else
 				break;
 		}
 		ptr += 2;
 	}
 	if (output->size - output->data > 0 && len - ptr > 0)
 		output->area[output->data++] = input[ptr];
 }
	/*
	* Utility functions for SSL:
	* Mostly generic functions that retrieve information from certificates
	*
	* Copyright (C) 2012 EXCELIANCE, Emeric Brun <ebrun@exceliance.fr>
	* Copyright (C) 2020 HAProxy Technologies, William Lallemand <wlallemand@haproxy.com>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version
	* 2 of the License, or (at your option) any later version.
	*/


	#include <haproxy/api.h>
	#include <haproxy/buf-t.h>
	#include <haproxy/chunk.h>
	#include <haproxy/openssl-compat.h>
	#include <haproxy/ssl_sock.h>
	#include <haproxy/ssl_utils.h>

	/* fill a buffer with the algorithm and size of a public key */
	int cert_get_pkey_algo(X509 crt, struct buffer out)
	{
	int bits = 0;
	int sig = TLSEXT_signature_anonymous;
	int len = -1;
	EVP_PKEY *pkey;

	pkey = X509_get_pubkey(crt);
	if (pkey) {
	bits = EVP_PKEY_bits(pkey);
	switch(EVP_PKEY_base_id(pkey)) {
	case EVP_PKEY_RSA:
	sig = TLSEXT_signature_rsa;
	break;
	case EVP_PKEY_EC:
	sig = TLSEXT_signature_ecdsa;
	break;
	case EVP_PKEY_DSA:
	sig = TLSEXT_signature_dsa;
	break;
	}
	EVP_PKEY_free(pkey);
	}

	switch(sig) {
	case TLSEXT_signature_rsa:
	len = chunk_printf(out, "RSA%d", bits);
	break;
	case TLSEXT_signature_ecdsa:
	len = chunk_printf(out, "EC%d", bits);
	break;
	case TLSEXT_signature_dsa:
	len = chunk_printf(out, "DSA%d", bits);
	break;
	default:
	return 0;
	}
	if (len < 0)
	return 0;
	return 1;
	}

	/* Extract a serial from a cert, and copy it to a chunk.
	* Returns 1 if serial is found and copied, 0 if no serial found and
	* -1 if output is not large enough.
	*/
	int ssl_sock_get_serial(X509 crt, struct buffer out)
	{
	ASN1_INTEGER *serial;

	serial = X509_get_serialNumber(crt);
	if (!serial)
	return 0;

	if (out->size < serial->length)
	return -1;

	memcpy(out->area, serial->data, serial->length);
	out->data = serial->length;
	return 1;
	}

	/* Extract a cert to der, and copy it to a chunk.
	* Returns 1 if the cert is found and copied, 0 on der conversion failure
	* and -1 if the output is not large enough.
	*/
	int ssl_sock_crt2der(X509 crt, struct buffer out)
	{
	int len;
	unsigned char p = (unsigned char ) out->area;

	len = i2d_X509(crt, NULL);
	if (len <= 0)
	return 1;

	if (out->size < len)
	return -1;

	i2d_X509(crt, &p);
	out->data = len;
	return 1;
	}


	/* Copy Date in ASN1_UTCTIME format in struct buffer out.
	* Returns 1 if serial is found and copied, 0 if no valid time found
	* and -1 if output is not large enough.
	*/
	int ssl_sock_get_time(ASN1_TIME tm, struct buffer out)
	{
	if (tm->type == V_ASN1_GENERALIZEDTIME) {
	ASN1_GENERALIZEDTIME gentm = (ASN1_GENERALIZEDTIME )tm;

	if (gentm->length < 12)
	return 0;
	if (gentm->data[0] != 0x32 \|\| gentm->data[1] != 0x30)
	return 0;
	if (out->size < gentm->length-2)
	return -1;

	memcpy(out->area, gentm->data+2, gentm->length-2);
	out->data = gentm->length-2;
	return 1;
	}
	else if (tm->type == V_ASN1_UTCTIME) {
	ASN1_UTCTIME utctm = (ASN1_UTCTIME )tm;

	if (utctm->length < 10)
	return 0;
	if (utctm->data[0] >= 0x35)
	return 0;
	if (out->size < utctm->length)
	return -1;

	memcpy(out->area, utctm->data, utctm->length);
	out->data = utctm->length;
	return 1;
	}

	return 0;
	}

	/* Extract an entry from a X509_NAME and copy its value to an output chunk.
	* Returns 1 if entry found, 0 if entry not found, or -1 if output not large enough.
	*/
	int ssl_sock_get_dn_entry(X509_NAME a, const struct buffer entry, int pos,
	struct buffer *out)
	{
	X509_NAME_ENTRY *ne;
	ASN1_OBJECT *obj;
	ASN1_STRING *data;
	const unsigned char *data_ptr;
	int data_len;
	int i, j, n;
	int cur = 0;
	const char *s;
	char tmp[128];
	int name_count;

	name_count = X509_NAME_entry_count(a);

	out->data = 0;
	for (i = 0; i < name_count; i++) {
	if (pos < 0)
	j = (name_count-1) - i;
	else
	j = i;

	ne = X509_NAME_get_entry(a, j);
	obj = X509_NAME_ENTRY_get_object(ne);
	data = X509_NAME_ENTRY_get_data(ne);
	data_ptr = ASN1_STRING_get0_data(data);
	data_len = ASN1_STRING_length(data);
	n = OBJ_obj2nid(obj);
	if ((n == NID_undef) \|\| ((s = OBJ_nid2sn(n)) == NULL)) {
	i2t_ASN1_OBJECT(tmp, sizeof(tmp), obj);
	s = tmp;
	}

	if (chunk_strcasecmp(entry, s) != 0)
	continue;

	if (pos < 0)
	cur--;
	else
	cur++;

	if (cur != pos)
	continue;

	if (data_len > out->size)
	return -1;

	memcpy(out->area, data_ptr, data_len);
	out->data = data_len;
	return 1;
	}

	return 0;

	}

	/*
	* Extract the DN in the specified format from the X509_NAME and copy result to a chunk.
	* Currently supports rfc2253 for returning LDAP V3 DNs.
	* Returns 1 if dn entries exist, 0 if no dn entry was found.
	*/
	int ssl_sock_get_dn_formatted(X509_NAME a, const struct buffer format, struct buffer *out)
	{
	BIO *bio = NULL;
	int ret = 0;
	int data_len = 0;

	if (chunk_strcmp(format, "rfc2253") == 0) {
	bio = BIO_new(BIO_s_mem());
	if (bio == NULL)
	goto out;

	if (X509_NAME_print_ex(bio, a, 0, XN_FLAG_RFC2253) < 0)
	goto out;

	if ((data_len = BIO_read(bio, out->area, out->size)) <= 0)
	goto out;

	out->data = data_len;

	ret = 1;
	}
	out:
	if (bio)
	BIO_free(bio);
	return ret;
	}

	/* Extract and format full DN from a X509_NAME and copy result into a chunk
	* Returns 1 if dn entries exits, 0 if no dn entry found or -1 if output is not large enough.
	*/
	int ssl_sock_get_dn_oneline(X509_NAME a, struct buffer out)
	{
	X509_NAME_ENTRY *ne;
	ASN1_OBJECT *obj;
	ASN1_STRING *data;
	const unsigned char *data_ptr;
	int data_len;
	int i, n, ln;
	int l = 0;
	const char *s;
	char *p;
	char tmp[128];
	int name_count;


	name_count = X509_NAME_entry_count(a);

	out->data = 0;
	p = out->area;
	for (i = 0; i < name_count; i++) {
	ne = X509_NAME_get_entry(a, i);
	obj = X509_NAME_ENTRY_get_object(ne);
	data = X509_NAME_ENTRY_get_data(ne);
	data_ptr = ASN1_STRING_get0_data(data);
	data_len = ASN1_STRING_length(data);
	n = OBJ_obj2nid(obj);
	if ((n == NID_undef) \|\| ((s = OBJ_nid2sn(n)) == NULL)) {
	i2t_ASN1_OBJECT(tmp, sizeof(tmp), obj);
	s = tmp;
	}
	ln = strlen(s);

	l += 1 + ln + 1 + data_len;
	if (l > out->size)
	return -1;
	out->data = l;

	*(p++)='/';
	memcpy(p, s, ln);
	p += ln;
	*(p++)='=';
	memcpy(p, data_ptr, data_len);
	p += data_len;
	}

	if (!out->data)
	return 0;

	return 1;
	}


	extern int ssl_client_crt_ref_index;

	/*
	* This function fetches the SSL certificate for a specific connection (either
	* client certificate or server certificate depending on the cert_peer
	* parameter).
	* When trying to get the peer certificate from the server side, we first try to
	* use the dedicated SSL_get_peer_certificate function, but we fall back to
	* trying to get the client certificate reference that might have been stored in
	* the SSL structure's ex_data during the verification process.
	* Returns NULL in case of failure.
	*/
	X509* ssl_sock_get_peer_certificate(SSL *ssl)
	{
	X509* cert;

	cert = SSL_get_peer_certificate(ssl);
	/* Get the client certificate reference stored in the SSL
	* structure's ex_data during the verification process. */
	if (!cert) {
	cert = SSL_get_ex_data(ssl, ssl_client_crt_ref_index);
	if (cert)
	X509_up_ref(cert);
	}

	return cert;
	}

	/*
	* Take an OpenSSL version in text format and return a numeric openssl version
	* Return 0 if it failed to parse the version
	*
	* https://www.openssl.org/docs/man1.1.1/man3/OPENSSL_VERSION_NUMBER.html
	*
	* MNNFFPPS: major minor fix patch status
	*
	* The status nibble has one of the values 0 for development, 1 to e for betas
	* 1 to 14, and f for release.
	*
	* for example
	*
	* 0x0090821f 0.9.8zh
	* 0x1000215f 1.0.2u
	* 0x30000000 3.0.0-alpha17
	* 0x30000002 3.0.0-beta2
	* 0x3000000e 3.0.0-beta14
	* 0x3000000f 3.0.0
	*/
	unsigned int openssl_version_parser(const char *version)
	{
	unsigned int numversion;
	unsigned int major = 0, minor = 0, fix = 0, patch = 0, status = 0;
	char p, end;

	p = (char *)version;

	if (!p \|\| !*p)
	return 0;

	major = strtol(p, &end, 10);
	if (*end != '.' \|\| major > 0xf)
	goto error;
	p = end + 1;

	minor = strtol(p, &end, 10);
	if (*end != '.' \|\| minor > 0xff)
	goto error;
	p = end + 1;

	fix = strtol(p, &end, 10);
	if (fix > 0xff)
	goto error;
	p = end;

	if (!*p) {
	/* end of the string, that's a release */
	status = 0xf;
	} else if (*p == '-') {
	/* after the hyphen, only the beta will increment the status
	* counter, all others versions will be considered as "dev" and
	* does not increment anything */
	p++;

	if (!strncmp(p, "beta", 4)) {
	p += 4;
	status = strtol(p, &end, 10);
	if (status > 14)
	goto error;
	}
	} else {
	/* that's a patch release */
	patch = 1;

	/* add the value of each letter */
	while (*p) {
	patch += (*p & ~0x20) - 'A';
	p++;
	}
	status = 0xf;
	}

	end:
	numversion = ((major & 0xf) << 28) \| ((minor & 0xff) << 20) \| ((fix & 0xff) << 12) \| ((patch & 0xff) << 4) \| (status & 0xf);
	return numversion;

	error:
	return 0;

	}

	/* Exclude GREASE (RFC8701) values from input buffer */
	void exclude_tls_grease(char input, int len, struct buffer output)
	{
	int ptr = 0;

	while (ptr < len - 1) {
	if (input[ptr] != input[ptr+1] \|\| (input[ptr] & 0x0f) != 0x0a) {
	if (output->data <= output->size - 2) {
	memcpy(output->area + output->data, input + ptr, 2);
	output->data += 2;
	} else
	break;
	}
	ptr += 2;
	}
	if (output->size - output->data > 0 && len - ptr > 0)
	output->area[output->data++] = input[ptr];
	}