haproxy/src/quic_tls.c
Amaury Denoyelle 93f5b4c8ae MINOR: quic: uniformize sending methods for handshake
Emission of packets during handshakes was implemented via an API which
uses two alternative ways to specify the list of frames.

The first one uses a NULL list of quic_enc_level as argument for
qc_prep_hpkts(). This was an implicit method to iterate on all qels
stored in quic_conn instance, with frames already inserted in their
corresponding quic_pktns.

The second method was used for retransmission. It uses a custom local
quic_enc_level list specified by the caller as input to qc_prep_hpkts().
Frames were accessible through <retransmit> list pointers of each
quic_enc_level used in an implicit mechanism.

This commit clarifies the API by using a single common method. Now
quic_enc_level list must always be specified by the caller. As for
frames list, each qels must set its new field <send_frms> pointer to the
list of frames to send. Callers of qc_prep_hpkts() are responsible to
always clear qels send list. This prevent a single instance of
quic_enc_level to be inserted while being attached to another list.

This allows notably to clean up some unnecessary code. First,
<retransmit> list of quic_enc_level is removed as it is replaced by new
<send_frms>. Also, it's now possible to use proper list_for_each_entry()
inside qc_prep_hpkts() to loop over each qels. Internal functions for
quic_enc_level selection is now removed.
2024-04-10 11:06:41 +02:00

1090 lines
34 KiB
C

#include <haproxy/quic_tls.h>
#include <string.h>
#include <openssl/evp.h>
#include <openssl/kdf.h>
#include <openssl/ssl.h>
#include <haproxy/buf.h>
#include <haproxy/chunk.h>
#include <haproxy/pool.h>
#include <haproxy/quic_ack.h>
#include <haproxy/quic_conn.h>
#include <haproxy/quic_rx.h>
#include <haproxy/quic_stream.h>
DECLARE_POOL(pool_head_quic_enc_level, "quic_enc_level", sizeof(struct quic_enc_level));
DECLARE_POOL(pool_head_quic_pktns, "quic_pktns", sizeof(struct quic_pktns));
DECLARE_POOL(pool_head_quic_tls_ctx, "quic_tls_ctx", sizeof(struct quic_tls_ctx));
DECLARE_POOL(pool_head_quic_tls_secret, "quic_tls_secret", QUIC_TLS_SECRET_LEN);
DECLARE_POOL(pool_head_quic_tls_iv, "quic_tls_iv", QUIC_TLS_IV_LEN);
DECLARE_POOL(pool_head_quic_tls_key, "quic_tls_key", QUIC_TLS_KEY_LEN);
DECLARE_POOL(pool_head_quic_crypto_buf, "quic_crypto_buf", sizeof(struct quic_crypto_buf));
DECLARE_STATIC_POOL(pool_head_quic_cstream, "quic_cstream", sizeof(struct quic_cstream));
/* Initial salt depending on QUIC version to derive client/server initial secrets.
* This one is for draft-29 QUIC version.
*/
const unsigned char initial_salt_draft_29[20] = {
0xaf, 0xbf, 0xec, 0x28, 0x99, 0x93, 0xd2, 0x4c,
0x9e, 0x97, 0x86, 0xf1, 0x9c, 0x61, 0x11, 0xe0,
0x43, 0x90, 0xa8, 0x99
};
const unsigned char initial_salt_v1[20] = {
0x38, 0x76, 0x2c, 0xf7, 0xf5, 0x59, 0x34, 0xb3,
0x4d, 0x17, 0x9a, 0xe6, 0xa4, 0xc8, 0x0c, 0xad,
0xcc, 0xbb, 0x7f, 0x0a
};
const unsigned char initial_salt_v2[20] = {
0x0d, 0xed, 0xe3, 0xde, 0xf7, 0x00, 0xa6, 0xdb,
0x81, 0x93, 0x81, 0xbe, 0x6e, 0x26, 0x9d, 0xcb,
0xf9, 0xbd, 0x2e, 0xd9
};
/* Dump the RX/TX secrets of <secs> QUIC TLS secrets. */
void quic_tls_keys_hexdump(struct buffer *buf,
const struct quic_tls_secrets *secs)
{
int i;
size_t aead_keylen;
size_t aead_ivlen;
size_t hp_len;
if (!secs->aead || !secs->hp)
return;
aead_keylen = (size_t)EVP_CIPHER_key_length(secs->aead);
aead_ivlen = (size_t)EVP_CIPHER_iv_length(secs->aead);
hp_len = (size_t)EVP_CIPHER_key_length(secs->hp);
chunk_appendf(buf, "\n key=");
for (i = 0; i < aead_keylen; i++)
chunk_appendf(buf, "%02x", secs->key[i]);
chunk_appendf(buf, "\n iv=");
for (i = 0; i < aead_ivlen; i++)
chunk_appendf(buf, "%02x", secs->iv[i]);
chunk_appendf(buf, "\n hp=");
for (i = 0; i < hp_len; i++)
chunk_appendf(buf, "%02x", secs->hp_key[i]);
}
/* Dump the RX/TX secrets of <kp> QUIC TLS key phase */
void quic_tls_kp_keys_hexdump(struct buffer *buf,
const struct quic_tls_kp *kp)
{
int i;
chunk_appendf(buf, "\n secret=");
for (i = 0; i < kp->secretlen; i++)
chunk_appendf(buf, "%02x", kp->secret[i]);
chunk_appendf(buf, "\n key=");
for (i = 0; i < kp->keylen; i++)
chunk_appendf(buf, "%02x", kp->key[i]);
chunk_appendf(buf, "\n iv=");
for (i = 0; i < kp->ivlen; i++)
chunk_appendf(buf, "%02x", kp->iv[i]);
}
/* Release the memory of <pktns> packet number space attached to <qc> QUIC connection. */
void quic_pktns_release(struct quic_conn *qc, struct quic_pktns **pktns)
{
if (!*pktns)
return;
quic_pktns_tx_pkts_release(*pktns, qc);
qc_release_pktns_frms(qc, *pktns);
quic_free_arngs(qc, &(*pktns)->rx.arngs);
LIST_DEL_INIT(&(*pktns)->list);
pool_free(pool_head_quic_pktns, *pktns);
*pktns = NULL;
}
/* Dump <secret> TLS secret. */
void quic_tls_secret_hexdump(struct buffer *buf,
const unsigned char *secret, size_t secret_len)
{
int i;
chunk_appendf(buf, " secret=");
for (i = 0; i < secret_len; i++)
chunk_appendf(buf, "%02x", secret[i]);
}
/* Release the memory allocated for <cs> CRYPTO stream */
void quic_cstream_free(struct quic_cstream *cs)
{
if (!cs) {
/* This is the case for ORTT encryption level */
return;
}
quic_free_ncbuf(&cs->rx.ncbuf);
qc_stream_desc_release(cs->desc, 0);
pool_free(pool_head_quic_cstream, cs);
}
/* Allocate a new QUIC stream for <qc>.
* Return it if succeeded, NULL if not.
*/
struct quic_cstream *quic_cstream_new(struct quic_conn *qc)
{
struct quic_cstream *cs, *ret_cs = NULL;
TRACE_ENTER(QUIC_EV_CONN_LPKT, qc);
cs = pool_alloc(pool_head_quic_cstream);
if (!cs) {
TRACE_ERROR("crypto stream allocation failed", QUIC_EV_CONN_INIT, qc);
goto leave;
}
cs->rx.offset = 0;
cs->rx.ncbuf = NCBUF_NULL;
cs->rx.offset = 0;
cs->tx.offset = 0;
cs->tx.sent_offset = 0;
cs->tx.buf = BUF_NULL;
cs->desc = qc_stream_desc_new((uint64_t)-1, -1, cs, qc);
if (!cs->desc) {
TRACE_ERROR("crypto stream allocation failed", QUIC_EV_CONN_INIT, qc);
goto err;
}
ret_cs = cs;
leave:
TRACE_LEAVE(QUIC_EV_CONN_LPKT, qc);
return ret_cs;
err:
pool_free(pool_head_quic_cstream, cs);
goto leave;
}
/* Uninitialize <qel> QUIC encryption level. Never fails. */
void quic_conn_enc_level_uninit(struct quic_conn *qc, struct quic_enc_level *qel)
{
int i;
TRACE_ENTER(QUIC_EV_CONN_CLOSE, qc);
for (i = 0; i < qel->tx.crypto.nb_buf; i++) {
if (qel->tx.crypto.bufs[i]) {
pool_free(pool_head_quic_crypto_buf, qel->tx.crypto.bufs[i]);
qel->tx.crypto.bufs[i] = NULL;
}
}
ha_free(&qel->tx.crypto.bufs);
quic_cstream_free(qel->cstream);
TRACE_LEAVE(QUIC_EV_CONN_CLOSE, qc);
}
/* Initialize QUIC TLS encryption level with <level<> as level for <qc> QUIC
* connection allocating everything needed.
*
* Returns 1 if succeeded, 0 if not. On error the caller is responsible to use
* quic_conn_enc_level_uninit() to cleanup partially allocated content.
*/
static int quic_conn_enc_level_init(struct quic_conn *qc,
struct quic_enc_level **el,
struct quic_pktns *pktns,
enum ssl_encryption_level_t level)
{
int ret = 0;
struct quic_enc_level *qel;
TRACE_ENTER(QUIC_EV_CONN_CLOSE, qc);
qel = pool_alloc(pool_head_quic_enc_level);
if (!qel)
goto leave;
LIST_INIT(&qel->el_send);
qel->send_frms = NULL;
qel->tx.crypto.bufs = NULL;
qel->tx.crypto.nb_buf = 0;
qel->cstream = NULL;
qel->pktns = pktns;
qel->level = level;
quic_tls_ctx_reset(&qel->tls_ctx);
qel->rx.pkts = EB_ROOT;
LIST_INIT(&qel->rx.pqpkts);
/* Allocate only one buffer. */
/* TODO: use a pool */
qel->tx.crypto.bufs = malloc(sizeof *qel->tx.crypto.bufs);
if (!qel->tx.crypto.bufs)
goto err;
qel->tx.crypto.bufs[0] = pool_alloc(pool_head_quic_crypto_buf);
if (!qel->tx.crypto.bufs[0])
goto err;
qel->tx.crypto.bufs[0]->sz = 0;
qel->tx.crypto.nb_buf = 1;
qel->tx.crypto.sz = 0;
qel->tx.crypto.offset = 0;
/* No CRYPTO data for early data TLS encryption level */
if (level == ssl_encryption_early_data)
qel->cstream = NULL;
else {
qel->cstream = quic_cstream_new(qc);
if (!qel->cstream)
goto err;
}
LIST_APPEND(&qc->qel_list, &qel->list);
*el = qel;
ret = 1;
leave:
TRACE_LEAVE(QUIC_EV_CONN_CLOSE, qc);
return ret;
err:
quic_conn_enc_level_uninit(qc, qel);
pool_free(pool_head_quic_enc_level, qel);
goto leave;
}
/* Allocate a QUIC TLS encryption with <level> as TLS stack encryption to be
* attached to <qc> QUIC connection. Also allocate the associated packet number
* space object with <pktns> as address to be attached to <qc> if not already
* allocated.
* Return 1 if succeeded, 0 if not.
*/
int qc_enc_level_alloc(struct quic_conn *qc, struct quic_pktns **pktns,
struct quic_enc_level **qel, enum ssl_encryption_level_t level)
{
int ret = 0;
BUG_ON(!qel || !pktns);
BUG_ON(*qel && !*pktns);
if (!*pktns && !quic_pktns_init(qc, pktns))
goto leave;
if (!*qel && !quic_conn_enc_level_init(qc, qel, *pktns, level))
goto leave;
ret = 1;
leave:
return ret;
}
/* Free the memory allocated to the encryption level attached to <qc> connection
* with <qel> as pointer address. Also remove it from the list of the encryption
* levels attached to this connection and reset its value to NULL.
* Never fails.
*/
void qc_enc_level_free(struct quic_conn *qc, struct quic_enc_level **qel)
{
if (!*qel)
return;
quic_tls_ctx_secs_free(&(*qel)->tls_ctx);
quic_conn_enc_level_uninit(qc, *qel);
LIST_DEL_INIT(&(*qel)->list);
pool_free(pool_head_quic_enc_level, *qel);
*qel = NULL;
}
int quic_hkdf_extract(const EVP_MD *md,
unsigned char *buf, size_t buflen,
const unsigned char *key, size_t keylen,
const unsigned char *salt, size_t saltlen)
{
EVP_PKEY_CTX *ctx;
ctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL);
if (!ctx)
return 0;
if (EVP_PKEY_derive_init(ctx) <= 0 ||
EVP_PKEY_CTX_hkdf_mode(ctx, EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY) <= 0 ||
EVP_PKEY_CTX_set_hkdf_md(ctx, md) <= 0 ||
EVP_PKEY_CTX_set1_hkdf_salt(ctx, salt, saltlen) <= 0 ||
EVP_PKEY_CTX_set1_hkdf_key(ctx, key, keylen) <= 0 ||
EVP_PKEY_derive(ctx, buf, &buflen) <= 0)
goto err;
EVP_PKEY_CTX_free(ctx);
return 1;
err:
EVP_PKEY_CTX_free(ctx);
return 0;
}
int quic_hkdf_expand(const EVP_MD *md,
unsigned char *buf, size_t buflen,
const unsigned char *key, size_t keylen,
const unsigned char *label, size_t labellen)
{
EVP_PKEY_CTX *ctx;
ctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL);
if (!ctx)
return 0;
if (EVP_PKEY_derive_init(ctx) <= 0 ||
EVP_PKEY_CTX_hkdf_mode(ctx, EVP_PKEY_HKDEF_MODE_EXPAND_ONLY) <= 0 ||
EVP_PKEY_CTX_set_hkdf_md(ctx, md) <= 0 ||
EVP_PKEY_CTX_set1_hkdf_key(ctx, key, keylen) <= 0 ||
EVP_PKEY_CTX_add1_hkdf_info(ctx, label, labellen) <= 0 ||
EVP_PKEY_derive(ctx, buf, &buflen) <= 0)
goto err;
EVP_PKEY_CTX_free(ctx);
return 1;
err:
EVP_PKEY_CTX_free(ctx);
return 0;
}
/* Extracts a peudo-random secret key from <key> which is eventually not
* pseudo-random and expand it to a new pseudo-random key into
* <buf> with <buflen> as key length according to HKDF specifications
* (https://datatracker.ietf.org/doc/html/rfc5869).
* According to this specifications it is highly recommended to use
* a salt, even if optional (NULL value).
* Return 1 if succeeded, 0 if not.
*/
int quic_hkdf_extract_and_expand(const EVP_MD *md,
unsigned char *buf, size_t buflen,
const unsigned char *key, size_t keylen,
const unsigned char *salt, size_t saltlen,
const unsigned char *label, size_t labellen)
{
EVP_PKEY_CTX *ctx;
ctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL);
if (!ctx)
return 0;
if (EVP_PKEY_derive_init(ctx) <= 0 ||
EVP_PKEY_CTX_hkdf_mode(ctx, EVP_PKEY_HKDEF_MODE_EXTRACT_AND_EXPAND) <= 0 ||
EVP_PKEY_CTX_set_hkdf_md(ctx, md) <= 0 ||
EVP_PKEY_CTX_set1_hkdf_salt(ctx, salt, saltlen) <= 0 ||
EVP_PKEY_CTX_set1_hkdf_key(ctx, key, keylen) <= 0 ||
EVP_PKEY_CTX_add1_hkdf_info(ctx, label, labellen) <= 0 ||
EVP_PKEY_derive(ctx, buf, &buflen) <= 0)
goto err;
EVP_PKEY_CTX_free(ctx);
return 1;
err:
EVP_PKEY_CTX_free(ctx);
return 0;
}
/* https://quicwg.org/base-drafts/draft-ietf-quic-tls.html#protection-keys
* refers to:
*
* https://tools.ietf.org/html/rfc8446#section-7.1:
* 7.1. Key Schedule
*
* The key derivation process makes use of the HKDF-Extract and
* HKDF-Expand functions as defined for HKDF [RFC5869], as well as the
* functions defined below:
*
* HKDF-Expand-Label(Secret, Label, Context, Length) =
* HKDF-Expand(Secret, HkdfLabel, Length)
*
* Where HkdfLabel is specified as:
*
* struct {
* uint16 length = Length;
* opaque label<7..255> = "tls13 " + Label;
* opaque context<0..255> = Context;
* } HkdfLabel;
*
* Derive-Secret(Secret, Label, Messages) =
* HKDF-Expand-Label(Secret, Label,
* Transcript-Hash(Messages), Hash.length)
*
*/
int quic_hkdf_expand_label(const EVP_MD *md,
unsigned char *buf, size_t buflen,
const unsigned char *key, size_t keylen,
const unsigned char *label, size_t labellen)
{
unsigned char hdkf_label[256], *pos;
const unsigned char hdkf_label_label[] = "tls13 ";
size_t hdkf_label_label_sz = sizeof hdkf_label_label - 1;
pos = hdkf_label;
*pos++ = buflen >> 8;
*pos++ = buflen & 0xff;
*pos++ = hdkf_label_label_sz + labellen;
memcpy(pos, hdkf_label_label, hdkf_label_label_sz);
pos += hdkf_label_label_sz;
memcpy(pos, label, labellen);
pos += labellen;
*pos++ = '\0';
return quic_hkdf_expand(md, buf, buflen,
key, keylen, hdkf_label, pos - hdkf_label);
}
/*
* This function derives two keys from <secret> is <ctx> as TLS cryptographic context.
* ->key is the TLS key to be derived to encrypt/decrypt data at TLS level.
* ->iv is the initialization vector to be used with ->key.
* ->hp_key is the key to be derived for header protection.
* Obviouly these keys have the same size becaused derived with the same TLS cryptographic context.
*/
int quic_tls_derive_keys(const EVP_CIPHER *aead, const EVP_CIPHER *hp,
const EVP_MD *md, const struct quic_version *qv,
unsigned char *key, size_t keylen,
unsigned char *iv, size_t ivlen,
unsigned char *hp_key, size_t hp_keylen,
const unsigned char *secret, size_t secretlen)
{
size_t aead_keylen = (size_t)EVP_CIPHER_key_length(aead);
size_t aead_ivlen = (size_t)EVP_CIPHER_iv_length(aead);
size_t hp_len = hp ? (size_t)EVP_CIPHER_key_length(hp) : 0;
if (aead_keylen > keylen || aead_ivlen > ivlen || hp_len > hp_keylen)
return 0;
if (!quic_hkdf_expand_label(md, key, aead_keylen, secret, secretlen,
qv->key_label,qv->key_label_len) ||
!quic_hkdf_expand_label(md, iv, aead_ivlen, secret, secretlen,
qv->iv_label, qv->iv_label_len) ||
(hp_key && !quic_hkdf_expand_label(md, hp_key, hp_len, secret, secretlen,
qv->hp_label, qv->hp_label_len)))
return 0;
return 1;
}
/*
* Derive the initial secret from <secret> and QUIC version dependent salt.
* Returns the size of the derived secret if succeeded, 0 if not.
*/
int quic_derive_initial_secret(const EVP_MD *md,
const unsigned char *initial_salt, size_t initial_salt_sz,
unsigned char *initial_secret, size_t initial_secret_sz,
const unsigned char *secret, size_t secret_sz)
{
if (!quic_hkdf_extract(md, initial_secret, initial_secret_sz, secret, secret_sz,
initial_salt, initial_salt_sz))
return 0;
return 1;
}
/*
* Derive the client initial secret from the initial secret.
* Returns the size of the derived secret if succeeded, 0 if not.
*/
int quic_tls_derive_initial_secrets(const EVP_MD *md,
unsigned char *rx, size_t rx_sz,
unsigned char *tx, size_t tx_sz,
const unsigned char *secret, size_t secret_sz,
int server)
{
const unsigned char client_label[] = "client in";
const unsigned char server_label[] = "server in";
const unsigned char *tx_label, *rx_label;
size_t rx_label_sz, tx_label_sz;
if (server) {
rx_label = client_label;
rx_label_sz = sizeof client_label;
tx_label = server_label;
tx_label_sz = sizeof server_label;
}
else {
rx_label = server_label;
rx_label_sz = sizeof server_label;
tx_label = client_label;
tx_label_sz = sizeof client_label;
}
if (!quic_hkdf_expand_label(md, rx, rx_sz, secret, secret_sz,
rx_label, rx_label_sz - 1) ||
!quic_hkdf_expand_label(md, tx, tx_sz, secret, secret_sz,
tx_label, tx_label_sz - 1))
return 0;
return 1;
}
/* Update <sec> secret key into <new_sec> according to RFC 9001 6.1.
* Always succeeds.
*/
int quic_tls_sec_update(const EVP_MD *md, const struct quic_version *qv,
unsigned char *new_sec, size_t new_seclen,
const unsigned char *sec, size_t seclen)
{
return quic_hkdf_expand_label(md, new_sec, new_seclen, sec, seclen,
qv->ku_label, qv->ku_label_len);
}
/*
* Build an IV into <iv> buffer with <ivlen> as size from <aead_iv> with
* <aead_ivlen> as size depending on <pn> packet number.
* This is the function which must be called to build an AEAD IV for the AEAD cryptographic algorithm
* used to encrypt/decrypt the QUIC packet payloads depending on the packet number <pn>.
*/
void quic_aead_iv_build(unsigned char *iv, size_t ivlen,
unsigned char *aead_iv, size_t aead_ivlen, uint64_t pn)
{
int i;
unsigned int shift;
unsigned char *pos = iv;
/* Input buffers must have the same size. */
BUG_ON(ivlen != aead_ivlen);
for (i = 0; i < ivlen - sizeof pn; i++)
*pos++ = *aead_iv++;
/* Only the remaining (sizeof pn) bytes are XOR'ed. */
shift = 56;
for (i = aead_ivlen - sizeof pn; i < aead_ivlen ; i++, shift -= 8)
*pos++ = *aead_iv++ ^ (pn >> shift);
}
/* Initialize the cipher context for RX part of <tls_ctx> QUIC TLS context.
* Return 1 if succeeded, 0 if not.
*/
int quic_tls_rx_ctx_init(EVP_CIPHER_CTX **rx_ctx,
const EVP_CIPHER *aead, unsigned char *key)
{
EVP_CIPHER_CTX *ctx;
int aead_nid = EVP_CIPHER_nid(aead);
ctx = EVP_CIPHER_CTX_new();
if (!ctx)
return 0;
if (!EVP_DecryptInit_ex(ctx, aead, NULL, NULL, NULL) ||
!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, QUIC_TLS_IV_LEN, NULL) ||
(aead_nid == NID_aes_128_ccm &&
!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, QUIC_TLS_TAG_LEN, NULL)) ||
!EVP_DecryptInit_ex(ctx, NULL, NULL, key, NULL))
goto err;
*rx_ctx = ctx;
return 1;
err:
EVP_CIPHER_CTX_free(ctx);
return 0;
}
/* Initialize <*aes_ctx> AES cipher context with <key> as key for encryption */
int quic_tls_enc_aes_ctx_init(EVP_CIPHER_CTX **aes_ctx,
const EVP_CIPHER *aes, unsigned char *key)
{
EVP_CIPHER_CTX *ctx;
ctx = EVP_CIPHER_CTX_new();
if (!ctx)
return 0;
if (!EVP_EncryptInit_ex(ctx, aes, NULL, key, NULL))
goto err;
*aes_ctx = ctx;
return 1;
err:
EVP_CIPHER_CTX_free(ctx);
return 0;
}
/* Encrypt <inlen> bytes from <in> buffer into <out> with <ctx> as AES
* cipher context. This is the responsibility of the caller to check there
* is at least <inlen> bytes of available space in <out> buffer.
* Return 1 if succeeded, 0 if not.
*/
int quic_tls_aes_encrypt(unsigned char *out,
const unsigned char *in, size_t inlen,
EVP_CIPHER_CTX *ctx)
{
int ret = 0;
if (!EVP_EncryptInit_ex(ctx, NULL, NULL, NULL, in) ||
!EVP_EncryptUpdate(ctx, out, &ret, out, inlen) ||
!EVP_EncryptFinal_ex(ctx, out, &ret))
return 0;
return 1;
}
/* Initialize <*aes_ctx> AES cipher context with <key> as key for decryption */
int quic_tls_dec_aes_ctx_init(EVP_CIPHER_CTX **aes_ctx,
const EVP_CIPHER *aes, unsigned char *key)
{
EVP_CIPHER_CTX *ctx;
ctx = EVP_CIPHER_CTX_new();
if (!ctx)
return 0;
if (!EVP_DecryptInit_ex(ctx, aes, NULL, key, NULL))
goto err;
*aes_ctx = ctx;
return 1;
err:
EVP_CIPHER_CTX_free(ctx);
return 0;
}
/* Decrypt <in> data into <out> with <ctx> as AES cipher context.
* This is the responsibility of the caller to check there is at least
* <outlen> bytes into <in> buffer.
* Return 1 if succeeded, 0 if not.
*/
int quic_tls_aes_decrypt(unsigned char *out,
const unsigned char *in, size_t inlen,
EVP_CIPHER_CTX *ctx)
{
int ret = 0;
if (!EVP_DecryptInit_ex(ctx, NULL, NULL, NULL, in) ||
!EVP_DecryptUpdate(ctx, out, &ret, out, inlen) ||
!EVP_DecryptFinal_ex(ctx, out, &ret))
return 0;
return 1;
}
/* Initialize the cipher context for TX part of <tls_ctx> QUIC TLS context.
* Return 1 if succeeded, 0 if not.
*/
int quic_tls_tx_ctx_init(EVP_CIPHER_CTX **tx_ctx,
const EVP_CIPHER *aead, unsigned char *key)
{
EVP_CIPHER_CTX *ctx;
int aead_nid = EVP_CIPHER_nid(aead);
ctx = EVP_CIPHER_CTX_new();
if (!ctx)
return 0;
if (!EVP_EncryptInit_ex(ctx, aead, NULL, NULL, NULL) ||
!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_IVLEN, QUIC_TLS_IV_LEN, NULL) ||
(aead_nid == NID_aes_128_ccm &&
!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, QUIC_TLS_TAG_LEN, NULL)) ||
!EVP_EncryptInit_ex(ctx, NULL, NULL, key, NULL))
goto err;
*tx_ctx = ctx;
return 1;
err:
EVP_CIPHER_CTX_free(ctx);
return 0;
}
/*
* https://quicwg.org/base-drafts/draft-ietf-quic-tls.html#aead
*
* 5.3. AEAD Usage
*
* Packets are protected prior to applying header protection (Section 5.4).
* The unprotected packet header is part of the associated data (A). When removing
* packet protection, an endpoint first removes the header protection.
* (...)
* These ciphersuites have a 16-byte authentication tag and produce an output 16
* bytes larger than their input.
* The key and IV for the packet are computed as described in Section 5.1. The nonce,
* N, is formed by combining the packet protection IV with the packet number. The 62
* bits of the reconstructed QUIC packet number in network byte order are left-padded
* with zeros to the size of the IV. The exclusive OR of the padded packet number and
* the IV forms the AEAD nonce.
*
* The associated data, A, for the AEAD is the contents of the QUIC header, starting
* from the flags byte in either the short or long header, up to and including the
* unprotected packet number.
*
* The input plaintext, P, for the AEAD is the payload of the QUIC packet, as described
* in [QUIC-TRANSPORT].
*
* The output ciphertext, C, of the AEAD is transmitted in place of P.
*
* Some AEAD functions have limits for how many packets can be encrypted under the same
* key and IV (see for example [AEBounds]). This might be lower than the packet number limit.
* An endpoint MUST initiate a key update (Section 6) prior to exceeding any limit set for
* the AEAD that is in use.
*/
/* Encrypt in place <buf> plaintext with <len> as length with QUIC_TLS_TAG_LEN
* included tailing bytes for the tag.
* Note that for CCM mode, we must set the the ciphertext length if AAD data
* are provided from <aad> buffer with <aad_len> as length. This is always the
* case here. So the caller of this function must provide <aad>.
*
* https://wiki.openssl.org/index.php/EVP_Authenticated_Encryption_and_Decryption
*/
int quic_tls_encrypt(unsigned char *buf, size_t len,
const unsigned char *aad, size_t aad_len,
EVP_CIPHER_CTX *ctx, const EVP_CIPHER *aead,
const unsigned char *iv)
{
int outlen;
int aead_nid = EVP_CIPHER_nid(aead);
if (!EVP_EncryptInit_ex(ctx, NULL, NULL, NULL, iv) ||
(aead_nid == NID_aes_128_ccm &&
!EVP_EncryptUpdate(ctx, NULL, &outlen, NULL, len)) ||
!EVP_EncryptUpdate(ctx, NULL, &outlen, aad, aad_len) ||
!EVP_EncryptUpdate(ctx, buf, &outlen, buf, len) ||
!EVP_EncryptFinal_ex(ctx, buf + outlen, &outlen) ||
!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, QUIC_TLS_TAG_LEN, buf + len))
return 0;
return 1;
}
/* Decrypt in place <buf> ciphertext with <len> as length with QUIC_TLS_TAG_LEN
* included tailing bytes for the tag.
* Note that for CCM mode, we must set the the ciphertext length if AAD data
* are provided from <aad> buffer with <aad_len> as length. This is always the
* case here. So the caller of this function must provide <aad>. Also not the
* there is no need to call EVP_DecryptFinal_ex for CCM mode.
*
* https://wiki.openssl.org/index.php/EVP_Authenticated_Encryption_and_Decryption
*/
int quic_tls_decrypt(unsigned char *buf, size_t len,
unsigned char *aad, size_t aad_len,
EVP_CIPHER_CTX *ctx, const EVP_CIPHER *aead,
const unsigned char *key, const unsigned char *iv)
{
int outlen;
int aead_nid = EVP_CIPHER_nid(aead);
if (!EVP_DecryptInit_ex(ctx, NULL, NULL, NULL, iv) ||
!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, QUIC_TLS_TAG_LEN,
buf + len - QUIC_TLS_TAG_LEN) ||
(aead_nid == NID_aes_128_ccm &&
!EVP_DecryptUpdate(ctx, NULL, &outlen, NULL, len - QUIC_TLS_TAG_LEN)) ||
!EVP_DecryptUpdate(ctx, NULL, &outlen, aad, aad_len) ||
!EVP_DecryptUpdate(ctx, buf, &outlen, buf, len - QUIC_TLS_TAG_LEN) ||
(aead_nid != NID_aes_128_ccm &&
!EVP_DecryptFinal_ex(ctx, buf + outlen, &outlen)))
return 0;
return 1;
}
/* Similar to quic_tls_decrypt(), except that this function does not decrypt
* in place its ciphertest if <out> output buffer ciphertest with <len> as length
* is different from <in> input buffer. This is the responbality of the caller
* to check that the output buffer has at least the same size as the input buffer.
* Note that for CCM mode, we must set the the ciphertext length if AAD data
* are provided from <aad> buffer with <aad_len> as length. This is always the
* case here. So the caller of this function must provide <aad>. Also note that
* there is no need to call EVP_DecryptFinal_ex for CCM mode.
*
* https://wiki.openssl.org/index.php/EVP_Authenticated_Encryption_and_Decryption
*
* Return 1 if succeeded, 0 if not.
*/
int quic_tls_decrypt2(unsigned char *out,
unsigned char *in, size_t len,
unsigned char *aad, size_t aad_len,
EVP_CIPHER_CTX *ctx, const EVP_CIPHER *aead,
const unsigned char *key, const unsigned char *iv)
{
int outlen;
int aead_nid = EVP_CIPHER_nid(aead);
len -= QUIC_TLS_TAG_LEN;
if (!EVP_DecryptInit_ex(ctx, NULL, NULL, NULL, iv) ||
!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_SET_TAG, QUIC_TLS_TAG_LEN, in + len) ||
(aead_nid == NID_aes_128_ccm &&
!EVP_DecryptUpdate(ctx, NULL, &outlen, NULL, len)) ||
!EVP_DecryptUpdate(ctx, NULL, &outlen, aad, aad_len) ||
!EVP_DecryptUpdate(ctx, out, &outlen, in, len) ||
(aead_nid != NID_aes_128_ccm &&
!EVP_DecryptFinal_ex(ctx, out + outlen, &outlen)))
return 0;
return 1;
}
/* Derive <key> and <iv> key and IV to be used to encrypt a retry token
* with <secret> which is not pseudo-random.
* Return 1 if succeeded, 0 if not.
*/
int quic_tls_derive_retry_token_secret(const EVP_MD *md,
unsigned char *key, size_t keylen,
unsigned char *iv, size_t ivlen,
const unsigned char *salt, size_t saltlen,
const unsigned char *secret, size_t secretlen)
{
unsigned char tmpkey[QUIC_TLS_KEY_LEN];
const unsigned char key_label[] = "retry token key";
const unsigned char iv_label[] = "retry token iv";
if (!quic_hkdf_extract(md, tmpkey, sizeof tmpkey,
secret, secretlen, salt, saltlen) ||
!quic_hkdf_expand(md, key, keylen, tmpkey, sizeof tmpkey,
key_label, sizeof key_label - 1) ||
!quic_hkdf_expand(md, iv, ivlen, tmpkey, sizeof tmpkey,
iv_label, sizeof iv_label - 1))
return 0;
return 1;
}
/* Generate the AEAD tag for the Retry packet <pkt> of <pkt_len> bytes and
* write it to <tag>. The tag is written just after the <pkt> area. It should
* be at least 16 bytes longs. <odcid> is the CID of the Initial packet
* received which triggers the Retry.
*
* Returns non-zero on success else zero.
*/
int quic_tls_generate_retry_integrity_tag(unsigned char *odcid, unsigned char odcid_len,
unsigned char *pkt, size_t pkt_len,
const struct quic_version *qv)
{
const EVP_CIPHER *evp = EVP_aes_128_gcm();
EVP_CIPHER_CTX *ctx;
/* encryption buffer - not used as only AEAD tag generation is proceed */
unsigned char *out = NULL;
/* address to store the AEAD tag */
unsigned char *tag = pkt + pkt_len;
int outlen, ret = 0;
ctx = EVP_CIPHER_CTX_new();
if (!ctx)
return 0;
/* rfc9001 5.8. Retry Packet Integrity
*
* AEAD is proceed over a pseudo-Retry packet used as AAD. It contains
* the ODCID len + data and the Retry packet itself.
*/
if (!EVP_EncryptInit_ex(ctx, evp, NULL, qv->retry_tag_key, qv->retry_tag_nonce) ||
/* specify pseudo-Retry as AAD */
!EVP_EncryptUpdate(ctx, NULL, &outlen, &odcid_len, sizeof(odcid_len)) ||
!EVP_EncryptUpdate(ctx, NULL, &outlen, odcid, odcid_len) ||
!EVP_EncryptUpdate(ctx, NULL, &outlen, pkt, pkt_len) ||
/* finalize */
!EVP_EncryptFinal_ex(ctx, out, &outlen) ||
/* store the tag */
!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_AEAD_GET_TAG, QUIC_TLS_TAG_LEN, tag)) {
goto out;
}
ret = 1;
out:
EVP_CIPHER_CTX_free(ctx);
return ret;
}
/* Derive new keys and ivs required for Key Update feature for <qc> QUIC
* connection.
* Return 1 if succeeded, 0 if not.
*/
int quic_tls_key_update(struct quic_conn *qc)
{
struct quic_tls_ctx *tls_ctx = &qc->ael->tls_ctx;
struct quic_tls_secrets *rx = &tls_ctx->rx;
struct quic_tls_secrets *tx = &tls_ctx->tx;
/* Used only for the traces */
struct quic_kp_trace kp_trace = {
.rx_sec = rx->secret,
.rx_seclen = rx->secretlen,
.tx_sec = tx->secret,
.tx_seclen = tx->secretlen,
};
/* The next key phase secrets to be derived */
struct quic_tls_kp *nxt_rx = &qc->ku.nxt_rx;
struct quic_tls_kp *nxt_tx = &qc->ku.nxt_tx;
const struct quic_version *ver =
qc->negotiated_version ? qc->negotiated_version : qc->original_version;
int ret = 0;
TRACE_ENTER(QUIC_EV_CONN_KP, qc);
nxt_rx = &qc->ku.nxt_rx;
nxt_tx = &qc->ku.nxt_tx;
TRACE_PRINTF(TRACE_LEVEL_DEVELOPER, QUIC_EV_CONN_SPPKTS, qc, 0, 0, 0,
"nxt_rx->secretlen=%llu rx->secretlen=%llu",
(ull)nxt_rx->secretlen, (ull)rx->secretlen);
/* Prepare new RX secrets */
if (!quic_tls_sec_update(rx->md, ver, nxt_rx->secret, nxt_rx->secretlen,
rx->secret, rx->secretlen)) {
TRACE_ERROR("New RX secret update failed", QUIC_EV_CONN_KP, qc);
goto leave;
}
if (!quic_tls_derive_keys(rx->aead, NULL, rx->md, ver,
nxt_rx->key, nxt_rx->keylen,
nxt_rx->iv, nxt_rx->ivlen, NULL, 0,
nxt_rx->secret, nxt_rx->secretlen)) {
TRACE_ERROR("New RX key derivation failed", QUIC_EV_CONN_KP, qc);
goto leave;
}
kp_trace.rx = nxt_rx;
/* Prepare new TX secrets */
if (!quic_tls_sec_update(tx->md, ver, nxt_tx->secret, nxt_tx->secretlen,
tx->secret, tx->secretlen)) {
TRACE_ERROR("New TX secret update failed", QUIC_EV_CONN_KP, qc);
goto leave;
}
if (!quic_tls_derive_keys(tx->aead, NULL, tx->md, ver,
nxt_tx->key, nxt_tx->keylen,
nxt_tx->iv, nxt_tx->ivlen, NULL, 0,
nxt_tx->secret, nxt_tx->secretlen)) {
TRACE_ERROR("New TX key derivation failed", QUIC_EV_CONN_KP, qc);
goto leave;
}
kp_trace.tx = nxt_tx;
if (nxt_rx->ctx) {
EVP_CIPHER_CTX_free(nxt_rx->ctx);
nxt_rx->ctx = NULL;
}
if (!quic_tls_rx_ctx_init(&nxt_rx->ctx, tls_ctx->rx.aead, nxt_rx->key)) {
TRACE_ERROR("could not initialize RX TLS cipher context", QUIC_EV_CONN_KP, qc);
goto leave;
}
if (nxt_tx->ctx) {
EVP_CIPHER_CTX_free(nxt_tx->ctx);
nxt_tx->ctx = NULL;
}
if (!quic_tls_tx_ctx_init(&nxt_tx->ctx, tls_ctx->tx.aead, nxt_tx->key)) {
TRACE_ERROR("could not initialize TX TLS cipher context", QUIC_EV_CONN_KP, qc);
goto leave;
}
ret = 1;
leave:
TRACE_PROTO("key update", QUIC_EV_CONN_KP, qc, &kp_trace);
TRACE_LEAVE(QUIC_EV_CONN_KP, qc);
return ret;
}
/* Rotate the Key Update information for <qc> QUIC connection.
* Must be used after having updated them.
* Always succeeds.
*/
void quic_tls_rotate_keys(struct quic_conn *qc)
{
struct quic_tls_ctx *tls_ctx = &qc->ael->tls_ctx;
unsigned char *curr_secret, *curr_iv, *curr_key;
EVP_CIPHER_CTX *curr_ctx;
TRACE_ENTER(QUIC_EV_CONN_RXPKT, qc);
/* Rotate the RX secrets */
curr_ctx = tls_ctx->rx.ctx;
curr_secret = tls_ctx->rx.secret;
curr_iv = tls_ctx->rx.iv;
curr_key = tls_ctx->rx.key;
tls_ctx->rx.ctx = qc->ku.nxt_rx.ctx;
tls_ctx->rx.secret = qc->ku.nxt_rx.secret;
tls_ctx->rx.iv = qc->ku.nxt_rx.iv;
tls_ctx->rx.key = qc->ku.nxt_rx.key;
qc->ku.nxt_rx.ctx = qc->ku.prv_rx.ctx;
qc->ku.nxt_rx.secret = qc->ku.prv_rx.secret;
qc->ku.nxt_rx.iv = qc->ku.prv_rx.iv;
qc->ku.nxt_rx.key = qc->ku.prv_rx.key;
qc->ku.prv_rx.ctx = curr_ctx;
qc->ku.prv_rx.secret = curr_secret;
qc->ku.prv_rx.iv = curr_iv;
qc->ku.prv_rx.key = curr_key;
qc->ku.prv_rx.pn = tls_ctx->rx.pn;
/* Update the TX secrets */
curr_ctx = tls_ctx->tx.ctx;
curr_secret = tls_ctx->tx.secret;
curr_iv = tls_ctx->tx.iv;
curr_key = tls_ctx->tx.key;
tls_ctx->tx.ctx = qc->ku.nxt_tx.ctx;
tls_ctx->tx.secret = qc->ku.nxt_tx.secret;
tls_ctx->tx.iv = qc->ku.nxt_tx.iv;
tls_ctx->tx.key = qc->ku.nxt_tx.key;
qc->ku.nxt_tx.ctx = curr_ctx;
qc->ku.nxt_tx.secret = curr_secret;
qc->ku.nxt_tx.iv = curr_iv;
qc->ku.nxt_tx.key = curr_key;
TRACE_LEAVE(QUIC_EV_CONN_RXPKT, qc);
}
/* Release the memory allocated for the QUIC TLS context with <ctx> as address. */
void quic_tls_ctx_free(struct quic_tls_ctx **ctx)
{
if (!*ctx)
return;
quic_tls_ctx_secs_free(*ctx);
pool_free(pool_head_quic_tls_ctx, *ctx);
*ctx = NULL;
}
/* Finalize <qc> QUIC connection:
* - allocated and initialize the Initial QUIC TLS context for negotiated
* version if needed,
* - derive the secrets for this context,
* - set them into the TLS stack,
*
* Return 1 if succeeded, 0 if not.
*/
int quic_tls_finalize(struct quic_conn *qc, int server)
{
int ret = 0;
TRACE_ENTER(QUIC_EV_CONN_NEW, qc);
if (!qc->negotiated_version)
goto done;
qc->nictx = pool_alloc(pool_head_quic_tls_ctx);
if (!qc->nictx)
goto err;
quic_tls_ctx_reset(qc->nictx);
if (!qc_new_isecs(qc, qc->nictx, qc->negotiated_version,
qc->odcid.data, qc->odcid.len, server))
goto err;
done:
ret = 1;
out:
TRACE_LEAVE(QUIC_EV_CONN_NEW, qc);
return ret;
err:
quic_tls_ctx_free(&qc->nictx);
goto out;
}