April 2020 - tor-commits - lists.torproject.org

[tor/maint-0.4.3] Merge branch 'bug33545_043_squashed' into maint-0.4.3
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit 55cb6c3fcdbeac31a88bcc62c0dbe5ded4605176 Merge: bfea7a732 f2f718bca Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Apr 13 14:13:44 2020 -0400 Merge branch 'bug33545_043_squashed' into maint-0.4.3 changes/bug33545 | 4 ++++ src/feature/control/control_hs.c | 9 ++++++++- src/feature/hs/hs_client.c | 7 +++++++ src/feature/hs/hs_client.h | 2 +- src/feature/hs/hs_descriptor.c | 8 ++++++-- src/test/test_hs_client.c | 4 ++++ src/test/test_hs_control.c | 14 ++++++++++++++ 7 files changed, 44 insertions(+), 4 deletions(-)

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[tor/maint-0.4.3] hs-v3: Don't allow registration of an all-zeroes client auth key.
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit 37bcc9f3d2f2df0335a42c9692e7d5deafc03514 Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Mar 30 16:09:52 2020 +0300 hs-v3: Don't allow registration of an all-zeroes client auth key. The client auth protocol allows attacker-controlled x25519 private keys being passed around, which allows an attacker to potentially trigger the all-zeroes assert for client_auth_sk in hs_descriptor.c:decrypt_descriptor_cookie(). We fixed that by making sure that an all-zeroes client auth key will not be used. There are no guidelines for validating x25519 private keys, and the assert was there as a sanity check for code flow issues (we don't want to enter that function with an unitialized key if client auth is being used). To avoid such crashes in the future, we also changed the assert to a BUG-and-err. --- changes/bug33545 | 4 ++++ src/feature/control/control_hs.c | 9 ++++++++- src/feature/hs/hs_client.h | 2 +- src/test/test_hs_control.c | 14 ++++++++++++++ 4 files changed, 27 insertions(+), 2 deletions(-) diff --git a/changes/bug33545 b/changes/bug33545 new file mode 100644 index 000000000..c051b0160 --- /dev/null +++ b/changes/bug33545 @@ -0,0 +1,4 @@ + o Minor bugfixes (hidden services): + - Block a client-side assert by disallowing the registration of an x25519 + client auth key that's all zeroes. Fixes bug 33545; bugfix on + 0.4.3.1-alpha. Patch based on patch from "cypherpunks". \ No newline at end of file diff --git a/src/feature/control/control_hs.c b/src/feature/control/control_hs.c index d3cd363f6..f5b331de9 100644 --- a/src/feature/control/control_hs.c +++ b/src/feature/control/control_hs.c @@ -50,11 +50,18 @@ parse_private_key_from_control_port(const char *client_privkey_str, if (base64_decode((char*)privkey->secret_key, sizeof(privkey->secret_key), key_blob, - strlen(key_blob)) != sizeof(privkey->secret_key)) { + strlen(key_blob)) != sizeof(privkey->secret_key)) { control_printf_endreply(conn, 512, "Failed to decode x25519 private key"); goto err; } + if (fast_mem_is_zero((const char*)privkey->secret_key, + sizeof(privkey->secret_key))) { + control_printf_endreply(conn, 553, + "Invalid private key \"%s\"", key_blob); + goto err; + } + retval = 0; err: diff --git a/src/feature/hs/hs_client.h b/src/feature/hs/hs_client.h index 3660bfa96..d0a3a7015 100644 --- a/src/feature/hs/hs_client.h +++ b/src/feature/hs/hs_client.h @@ -45,7 +45,7 @@ typedef enum { REGISTER_SUCCESS_AND_DECRYPTED, /* We failed to register these credentials, because of a bad HS address. */ REGISTER_FAIL_BAD_ADDRESS, - /* We failed to register these credentials, because of a bad HS address. */ + /* We failed to store these credentials in a persistent file on disk. */ REGISTER_FAIL_PERMANENT_STORAGE, } hs_client_register_auth_status_t; diff --git a/src/test/test_hs_control.c b/src/test/test_hs_control.c index 9277711d2..8ba9f1173 100644 --- a/src/test/test_hs_control.c +++ b/src/test/test_hs_control.c @@ -467,6 +467,20 @@ test_hs_control_bad_onion_client_auth_add(void *arg) cp1 = buf_get_contents(TO_CONN(&conn)->outbuf, &sz); tt_str_op(cp1, OP_EQ, "512 Failed to decode x25519 private key\r\n"); + tor_free(cp1); + tor_free(args); + + /* Register with an all zero client key */ + args = tor_strdup("jt4grrjwzyz3pjkylwfau5xnjaj23vxmhskqaeyfhrfylelw4hvxcuyd " + "x25519:AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA="); + retval = handle_control_command(&conn, (uint32_t) strlen(args), args); + tt_int_op(retval, OP_EQ, 0); + + /* Check contents */ + cp1 = buf_get_contents(TO_CONN(&conn)->outbuf, &sz); + tt_str_op(cp1, OP_EQ, "553 Invalid private key \"AAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAA=\"\r\n"); + client_auths = get_hs_client_auths_map(); tt_assert(!client_auths);

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[tor/master] hs-v3: Change all-zeroes hard-assert to a BUG-and-err.
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit f2f718bca504d0fe1cce566185f8c17e23862335 Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Mar 30 16:33:30 2020 +0300 hs-v3: Change all-zeroes hard-assert to a BUG-and-err. And also disallow all-zeroes keys from the filesystem; add a test for it too. --- src/feature/hs/hs_client.c | 7 +++++++ src/feature/hs/hs_descriptor.c | 8 ++++++-- src/test/test_hs_client.c | 4 ++++ 3 files changed, 17 insertions(+), 2 deletions(-) diff --git a/src/feature/hs/hs_client.c b/src/feature/hs/hs_client.c index af8cb0b41..da1202b64 100644 --- a/src/feature/hs/hs_client.c +++ b/src/feature/hs/hs_client.c @@ -2132,6 +2132,13 @@ parse_auth_file_content(const char *client_key_str) "can't be decoded: %s", seckey_b32); goto err; } + + if (fast_mem_is_zero((const char*)auth->enc_seckey.secret_key, + sizeof(auth->enc_seckey.secret_key))) { + log_warn(LD_REND, "Client authorization private key can't be all-zeroes"); + goto err; + } + strncpy(auth->onion_address, onion_address, HS_SERVICE_ADDR_LEN_BASE32); /* We are reading this from the disk, so set the permanent flag anyway. */ diff --git a/src/feature/hs/hs_descriptor.c b/src/feature/hs/hs_descriptor.c index 65d6c7a58..27823aa79 100644 --- a/src/feature/hs/hs_descriptor.c +++ b/src/feature/hs/hs_descriptor.c @@ -1424,10 +1424,14 @@ decrypt_descriptor_cookie(const hs_descriptor_t *desc, tor_assert(!fast_mem_is_zero( (char *) &desc->superencrypted_data.auth_ephemeral_pubkey, sizeof(desc->superencrypted_data.auth_ephemeral_pubkey))); - tor_assert(!fast_mem_is_zero((char *) client_auth_sk, - sizeof(*client_auth_sk))); tor_assert(!fast_mem_is_zero((char *) desc->subcredential, DIGEST256_LEN)); + /* Catch potential code-flow cases of an unitialized private key sneaking + * into this function. */ + if (BUG(fast_mem_is_zero((char *)client_auth_sk, sizeof(*client_auth_sk)))) { + goto done; + } + /* Get the KEYS component to derive the CLIENT-ID and COOKIE-KEY. */ keystream_length = build_descriptor_cookie_keys(desc->subcredential, DIGEST256_LEN, diff --git a/src/test/test_hs_client.c b/src/test/test_hs_client.c index 5f7fe9c40..4d938e463 100644 --- a/src/test/test_hs_client.c +++ b/src/test/test_hs_client.c @@ -732,6 +732,10 @@ test_parse_auth_file_content(void *arg) /* Bigger key than it should be */ tt_assert(!parse_auth_file_content("xx:descriptor:x25519:" "vjqea4jbhwwc4hto7ekyvqfbeodghbaq6nxi45hz4wr3qvhqv3yqa")); + /* All-zeroes key */ + tt_assert(!parse_auth_file_content("xx:descriptor:x25519:" + "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa")); + done: tor_free(auth); }

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[tor/maint-0.4.3] hs-v3: Change all-zeroes hard-assert to a BUG-and-err.
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit f2f718bca504d0fe1cce566185f8c17e23862335 Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Mar 30 16:33:30 2020 +0300 hs-v3: Change all-zeroes hard-assert to a BUG-and-err. And also disallow all-zeroes keys from the filesystem; add a test for it too. --- src/feature/hs/hs_client.c | 7 +++++++ src/feature/hs/hs_descriptor.c | 8 ++++++-- src/test/test_hs_client.c | 4 ++++ 3 files changed, 17 insertions(+), 2 deletions(-) diff --git a/src/feature/hs/hs_client.c b/src/feature/hs/hs_client.c index af8cb0b41..da1202b64 100644 --- a/src/feature/hs/hs_client.c +++ b/src/feature/hs/hs_client.c @@ -2132,6 +2132,13 @@ parse_auth_file_content(const char *client_key_str) "can't be decoded: %s", seckey_b32); goto err; } + + if (fast_mem_is_zero((const char*)auth->enc_seckey.secret_key, + sizeof(auth->enc_seckey.secret_key))) { + log_warn(LD_REND, "Client authorization private key can't be all-zeroes"); + goto err; + } + strncpy(auth->onion_address, onion_address, HS_SERVICE_ADDR_LEN_BASE32); /* We are reading this from the disk, so set the permanent flag anyway. */ diff --git a/src/feature/hs/hs_descriptor.c b/src/feature/hs/hs_descriptor.c index 65d6c7a58..27823aa79 100644 --- a/src/feature/hs/hs_descriptor.c +++ b/src/feature/hs/hs_descriptor.c @@ -1424,10 +1424,14 @@ decrypt_descriptor_cookie(const hs_descriptor_t *desc, tor_assert(!fast_mem_is_zero( (char *) &desc->superencrypted_data.auth_ephemeral_pubkey, sizeof(desc->superencrypted_data.auth_ephemeral_pubkey))); - tor_assert(!fast_mem_is_zero((char *) client_auth_sk, - sizeof(*client_auth_sk))); tor_assert(!fast_mem_is_zero((char *) desc->subcredential, DIGEST256_LEN)); + /* Catch potential code-flow cases of an unitialized private key sneaking + * into this function. */ + if (BUG(fast_mem_is_zero((char *)client_auth_sk, sizeof(*client_auth_sk)))) { + goto done; + } + /* Get the KEYS component to derive the CLIENT-ID and COOKIE-KEY. */ keystream_length = build_descriptor_cookie_keys(desc->subcredential, DIGEST256_LEN, diff --git a/src/test/test_hs_client.c b/src/test/test_hs_client.c index 5f7fe9c40..4d938e463 100644 --- a/src/test/test_hs_client.c +++ b/src/test/test_hs_client.c @@ -732,6 +732,10 @@ test_parse_auth_file_content(void *arg) /* Bigger key than it should be */ tt_assert(!parse_auth_file_content("xx:descriptor:x25519:" "vjqea4jbhwwc4hto7ekyvqfbeodghbaq6nxi45hz4wr3qvhqv3yqa")); + /* All-zeroes key */ + tt_assert(!parse_auth_file_content("xx:descriptor:x25519:" + "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa")); + done: tor_free(auth); }

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[tor/master] hs-v3: Don't allow registration of an all-zeroes client auth key.
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit 37bcc9f3d2f2df0335a42c9692e7d5deafc03514 Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Mar 30 16:09:52 2020 +0300 hs-v3: Don't allow registration of an all-zeroes client auth key. The client auth protocol allows attacker-controlled x25519 private keys being passed around, which allows an attacker to potentially trigger the all-zeroes assert for client_auth_sk in hs_descriptor.c:decrypt_descriptor_cookie(). We fixed that by making sure that an all-zeroes client auth key will not be used. There are no guidelines for validating x25519 private keys, and the assert was there as a sanity check for code flow issues (we don't want to enter that function with an unitialized key if client auth is being used). To avoid such crashes in the future, we also changed the assert to a BUG-and-err. --- changes/bug33545 | 4 ++++ src/feature/control/control_hs.c | 9 ++++++++- src/feature/hs/hs_client.h | 2 +- src/test/test_hs_control.c | 14 ++++++++++++++ 4 files changed, 27 insertions(+), 2 deletions(-) diff --git a/changes/bug33545 b/changes/bug33545 new file mode 100644 index 000000000..c051b0160 --- /dev/null +++ b/changes/bug33545 @@ -0,0 +1,4 @@ + o Minor bugfixes (hidden services): + - Block a client-side assert by disallowing the registration of an x25519 + client auth key that's all zeroes. Fixes bug 33545; bugfix on + 0.4.3.1-alpha. Patch based on patch from "cypherpunks". \ No newline at end of file diff --git a/src/feature/control/control_hs.c b/src/feature/control/control_hs.c index d3cd363f6..f5b331de9 100644 --- a/src/feature/control/control_hs.c +++ b/src/feature/control/control_hs.c @@ -50,11 +50,18 @@ parse_private_key_from_control_port(const char *client_privkey_str, if (base64_decode((char*)privkey->secret_key, sizeof(privkey->secret_key), key_blob, - strlen(key_blob)) != sizeof(privkey->secret_key)) { + strlen(key_blob)) != sizeof(privkey->secret_key)) { control_printf_endreply(conn, 512, "Failed to decode x25519 private key"); goto err; } + if (fast_mem_is_zero((const char*)privkey->secret_key, + sizeof(privkey->secret_key))) { + control_printf_endreply(conn, 553, + "Invalid private key \"%s\"", key_blob); + goto err; + } + retval = 0; err: diff --git a/src/feature/hs/hs_client.h b/src/feature/hs/hs_client.h index 3660bfa96..d0a3a7015 100644 --- a/src/feature/hs/hs_client.h +++ b/src/feature/hs/hs_client.h @@ -45,7 +45,7 @@ typedef enum { REGISTER_SUCCESS_AND_DECRYPTED, /* We failed to register these credentials, because of a bad HS address. */ REGISTER_FAIL_BAD_ADDRESS, - /* We failed to register these credentials, because of a bad HS address. */ + /* We failed to store these credentials in a persistent file on disk. */ REGISTER_FAIL_PERMANENT_STORAGE, } hs_client_register_auth_status_t; diff --git a/src/test/test_hs_control.c b/src/test/test_hs_control.c index 9277711d2..8ba9f1173 100644 --- a/src/test/test_hs_control.c +++ b/src/test/test_hs_control.c @@ -467,6 +467,20 @@ test_hs_control_bad_onion_client_auth_add(void *arg) cp1 = buf_get_contents(TO_CONN(&conn)->outbuf, &sz); tt_str_op(cp1, OP_EQ, "512 Failed to decode x25519 private key\r\n"); + tor_free(cp1); + tor_free(args); + + /* Register with an all zero client key */ + args = tor_strdup("jt4grrjwzyz3pjkylwfau5xnjaj23vxmhskqaeyfhrfylelw4hvxcuyd " + "x25519:AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA="); + retval = handle_control_command(&conn, (uint32_t) strlen(args), args); + tt_int_op(retval, OP_EQ, 0); + + /* Check contents */ + cp1 = buf_get_contents(TO_CONN(&conn)->outbuf, &sz); + tt_str_op(cp1, OP_EQ, "553 Invalid private key \"AAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAA=\"\r\n"); + client_auths = get_hs_client_auths_map(); tt_assert(!client_auths);

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[tor/master] Merge branch 'bug33545_043_squashed' into maint-0.4.3
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit 55cb6c3fcdbeac31a88bcc62c0dbe5ded4605176 Merge: bfea7a732 f2f718bca Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Apr 13 14:13:44 2020 -0400 Merge branch 'bug33545_043_squashed' into maint-0.4.3 changes/bug33545 | 4 ++++ src/feature/control/control_hs.c | 9 ++++++++- src/feature/hs/hs_client.c | 7 +++++++ src/feature/hs/hs_client.h | 2 +- src/feature/hs/hs_descriptor.c | 8 ++++++-- src/test/test_hs_client.c | 4 ++++ src/test/test_hs_control.c | 14 ++++++++++++++ 7 files changed, 44 insertions(+), 4 deletions(-)

1 0

[tor/master] Merge branch 'maint-0.4.3'
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit e22a8d9c956f838138a7e5bc0714b1bb99f0e2a5 Merge: 80031db32 55cb6c3fc Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Apr 13 14:14:41 2020 -0400 Merge branch 'maint-0.4.3' changes/bug33545 | 4 ++++ src/feature/control/control_hs.c | 9 ++++++++- src/feature/hs/hs_client.c | 7 +++++++ src/feature/hs/hs_client.h | 2 +- src/feature/hs/hs_descriptor.c | 8 ++++++-- src/test/test_hs_client.c | 4 ++++ src/test/test_hs_control.c | 14 ++++++++++++++ 7 files changed, 44 insertions(+), 4 deletions(-) diff --cc src/feature/hs/hs_descriptor.c index a39a4a09c,d1c81bbff..50a46fb40 --- a/src/feature/hs/hs_descriptor.c +++ b/src/feature/hs/hs_descriptor.c @@@ -1429,14 -1434,17 +1429,18 @@@ decrypt_descriptor_cookie(const hs_desc tor_assert(!fast_mem_is_zero( (char *) &desc->superencrypted_data.auth_ephemeral_pubkey, sizeof(desc->superencrypted_data.auth_ephemeral_pubkey))); - tor_assert(!fast_mem_is_zero((char *) client_auth_sk, - sizeof(*client_auth_sk))); - tor_assert(!fast_mem_is_zero((char *) desc->subcredential, DIGEST256_LEN)); + tor_assert(!fast_mem_is_zero((char *) desc->subcredential.subcred, + DIGEST256_LEN)); + /* Catch potential code-flow cases of an unitialized private key sneaking + * into this function. */ + if (BUG(fast_mem_is_zero((char *)client_auth_sk, sizeof(*client_auth_sk)))) { + goto done; + } + /* Get the KEYS component to derive the CLIENT-ID and COOKIE-KEY. */ keystream_length = - build_descriptor_cookie_keys(desc->subcredential, DIGEST256_LEN, + build_descriptor_cookie_keys(&desc->subcredential, client_auth_sk, &desc->superencrypted_data.auth_ephemeral_pubkey, &keystream);

1 0

[tor/release-0.4.3] hs-v3: Don't allow registration of an all-zeroes client auth key.
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit 37bcc9f3d2f2df0335a42c9692e7d5deafc03514 Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Mar 30 16:09:52 2020 +0300 hs-v3: Don't allow registration of an all-zeroes client auth key. The client auth protocol allows attacker-controlled x25519 private keys being passed around, which allows an attacker to potentially trigger the all-zeroes assert for client_auth_sk in hs_descriptor.c:decrypt_descriptor_cookie(). We fixed that by making sure that an all-zeroes client auth key will not be used. There are no guidelines for validating x25519 private keys, and the assert was there as a sanity check for code flow issues (we don't want to enter that function with an unitialized key if client auth is being used). To avoid such crashes in the future, we also changed the assert to a BUG-and-err. --- changes/bug33545 | 4 ++++ src/feature/control/control_hs.c | 9 ++++++++- src/feature/hs/hs_client.h | 2 +- src/test/test_hs_control.c | 14 ++++++++++++++ 4 files changed, 27 insertions(+), 2 deletions(-) diff --git a/changes/bug33545 b/changes/bug33545 new file mode 100644 index 000000000..c051b0160 --- /dev/null +++ b/changes/bug33545 @@ -0,0 +1,4 @@ + o Minor bugfixes (hidden services): + - Block a client-side assert by disallowing the registration of an x25519 + client auth key that's all zeroes. Fixes bug 33545; bugfix on + 0.4.3.1-alpha. Patch based on patch from "cypherpunks". \ No newline at end of file diff --git a/src/feature/control/control_hs.c b/src/feature/control/control_hs.c index d3cd363f6..f5b331de9 100644 --- a/src/feature/control/control_hs.c +++ b/src/feature/control/control_hs.c @@ -50,11 +50,18 @@ parse_private_key_from_control_port(const char *client_privkey_str, if (base64_decode((char*)privkey->secret_key, sizeof(privkey->secret_key), key_blob, - strlen(key_blob)) != sizeof(privkey->secret_key)) { + strlen(key_blob)) != sizeof(privkey->secret_key)) { control_printf_endreply(conn, 512, "Failed to decode x25519 private key"); goto err; } + if (fast_mem_is_zero((const char*)privkey->secret_key, + sizeof(privkey->secret_key))) { + control_printf_endreply(conn, 553, + "Invalid private key \"%s\"", key_blob); + goto err; + } + retval = 0; err: diff --git a/src/feature/hs/hs_client.h b/src/feature/hs/hs_client.h index 3660bfa96..d0a3a7015 100644 --- a/src/feature/hs/hs_client.h +++ b/src/feature/hs/hs_client.h @@ -45,7 +45,7 @@ typedef enum { REGISTER_SUCCESS_AND_DECRYPTED, /* We failed to register these credentials, because of a bad HS address. */ REGISTER_FAIL_BAD_ADDRESS, - /* We failed to register these credentials, because of a bad HS address. */ + /* We failed to store these credentials in a persistent file on disk. */ REGISTER_FAIL_PERMANENT_STORAGE, } hs_client_register_auth_status_t; diff --git a/src/test/test_hs_control.c b/src/test/test_hs_control.c index 9277711d2..8ba9f1173 100644 --- a/src/test/test_hs_control.c +++ b/src/test/test_hs_control.c @@ -467,6 +467,20 @@ test_hs_control_bad_onion_client_auth_add(void *arg) cp1 = buf_get_contents(TO_CONN(&conn)->outbuf, &sz); tt_str_op(cp1, OP_EQ, "512 Failed to decode x25519 private key\r\n"); + tor_free(cp1); + tor_free(args); + + /* Register with an all zero client key */ + args = tor_strdup("jt4grrjwzyz3pjkylwfau5xnjaj23vxmhskqaeyfhrfylelw4hvxcuyd " + "x25519:AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA="); + retval = handle_control_command(&conn, (uint32_t) strlen(args), args); + tt_int_op(retval, OP_EQ, 0); + + /* Check contents */ + cp1 = buf_get_contents(TO_CONN(&conn)->outbuf, &sz); + tt_str_op(cp1, OP_EQ, "553 Invalid private key \"AAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAA=\"\r\n"); + client_auths = get_hs_client_auths_map(); tt_assert(!client_auths);

1 0

[tor/release-0.4.3] hs-v3: Change all-zeroes hard-assert to a BUG-and-err.
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit f2f718bca504d0fe1cce566185f8c17e23862335 Author: George Kadianakis <desnacked(a)riseup.net> Date: Mon Mar 30 16:33:30 2020 +0300 hs-v3: Change all-zeroes hard-assert to a BUG-and-err. And also disallow all-zeroes keys from the filesystem; add a test for it too. --- src/feature/hs/hs_client.c | 7 +++++++ src/feature/hs/hs_descriptor.c | 8 ++++++-- src/test/test_hs_client.c | 4 ++++ 3 files changed, 17 insertions(+), 2 deletions(-) diff --git a/src/feature/hs/hs_client.c b/src/feature/hs/hs_client.c index af8cb0b41..da1202b64 100644 --- a/src/feature/hs/hs_client.c +++ b/src/feature/hs/hs_client.c @@ -2132,6 +2132,13 @@ parse_auth_file_content(const char *client_key_str) "can't be decoded: %s", seckey_b32); goto err; } + + if (fast_mem_is_zero((const char*)auth->enc_seckey.secret_key, + sizeof(auth->enc_seckey.secret_key))) { + log_warn(LD_REND, "Client authorization private key can't be all-zeroes"); + goto err; + } + strncpy(auth->onion_address, onion_address, HS_SERVICE_ADDR_LEN_BASE32); /* We are reading this from the disk, so set the permanent flag anyway. */ diff --git a/src/feature/hs/hs_descriptor.c b/src/feature/hs/hs_descriptor.c index 65d6c7a58..27823aa79 100644 --- a/src/feature/hs/hs_descriptor.c +++ b/src/feature/hs/hs_descriptor.c @@ -1424,10 +1424,14 @@ decrypt_descriptor_cookie(const hs_descriptor_t *desc, tor_assert(!fast_mem_is_zero( (char *) &desc->superencrypted_data.auth_ephemeral_pubkey, sizeof(desc->superencrypted_data.auth_ephemeral_pubkey))); - tor_assert(!fast_mem_is_zero((char *) client_auth_sk, - sizeof(*client_auth_sk))); tor_assert(!fast_mem_is_zero((char *) desc->subcredential, DIGEST256_LEN)); + /* Catch potential code-flow cases of an unitialized private key sneaking + * into this function. */ + if (BUG(fast_mem_is_zero((char *)client_auth_sk, sizeof(*client_auth_sk)))) { + goto done; + } + /* Get the KEYS component to derive the CLIENT-ID and COOKIE-KEY. */ keystream_length = build_descriptor_cookie_keys(desc->subcredential, DIGEST256_LEN, diff --git a/src/test/test_hs_client.c b/src/test/test_hs_client.c index 5f7fe9c40..4d938e463 100644 --- a/src/test/test_hs_client.c +++ b/src/test/test_hs_client.c @@ -732,6 +732,10 @@ test_parse_auth_file_content(void *arg) /* Bigger key than it should be */ tt_assert(!parse_auth_file_content("xx:descriptor:x25519:" "vjqea4jbhwwc4hto7ekyvqfbeodghbaq6nxi45hz4wr3qvhqv3yqa")); + /* All-zeroes key */ + tt_assert(!parse_auth_file_content("xx:descriptor:x25519:" + "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa")); + done: tor_free(auth); }

1 0

[tor/release-0.4.3] Merge branch 'bug33545_043_squashed' into maint-0.4.3
by nickm＠torproject.org 13 Apr '20

13 Apr '20

commit 55cb6c3fcdbeac31a88bcc62c0dbe5ded4605176 Merge: bfea7a732 f2f718bca Author: Nick Mathewson <nickm(a)torproject.org> Date: Mon Apr 13 14:13:44 2020 -0400 Merge branch 'bug33545_043_squashed' into maint-0.4.3 changes/bug33545 | 4 ++++ src/feature/control/control_hs.c | 9 ++++++++- src/feature/hs/hs_client.c | 7 +++++++ src/feature/hs/hs_client.h | 2 +- src/feature/hs/hs_descriptor.c | 8 ++++++-- src/test/test_hs_client.c | 4 ++++ src/test/test_hs_control.c | 14 ++++++++++++++ 7 files changed, 44 insertions(+), 4 deletions(-)

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