From fdb50b8256f1038d5bc4f906b41605cacc769bf4 Mon Sep 17 00:00:00 2001 From: Dimitri Staessens Date: Sun, 14 Jun 2026 16:16:03 +0200 Subject: irmd: Deliver flow re-keying MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Re-key each encrypted flow's batch root periodically so a long-lived flow never exhausts or over-uses a single root. The IRMd re-runs the OAP exchange with the peer IRMd over the flow-update relay. The per-flow re-keying state is tracked in the registry (reg_flow). A re-key delivers one root seed from the OAP exchange. keyrot immediately HKDF-expands it into 128 node keys (KR_NODES_SZ = 128 × 32 B) and wipes the root. Then each of the 128 node keys is itself a root → HKDF-expanded into 64 (2^KEY_NODE_BITS) leaf keys, forked per direction; each leaf key is the actual AEAD key, good for 2^20 packets (the low counter bits are its nonce/seq). If the number of keys runs low, a re-key will be triggered (KEY_REKEY_WATERMARK). The rekey is signalled out of band to the application. The rbuff ACL is generalized into a flags word, so an RB_REKEY bit rides alongside the access RB_RD/RB_WR and FLOWDOWN/FLOWPEER bits. The RD and WR bits are revised ditching the fcntl historical weirdness. The seed is pulled via flow_read/flow_write, installed with crypt_rekey(). TX holds the old epoch until the peer is observed on the new one (or a grace deadline elapses), promoted from both the read and write paths so a recv-mostly flow still advances. Also fix the FLOW_ACCEPT and FLOW_ALLOC handlers, which on a key-buffer allocation failure returned from inside the cleanup-push region: that leaked the reply message and skipped both the stack-key scrub and the cleanup pop. Signed-off-by: Dimitri Staessens Signed-off-by: Sander Vrijders --- src/lib/ssm/tests/rbuff_test.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) (limited to 'src/lib/ssm/tests') diff --git a/src/lib/ssm/tests/rbuff_test.c b/src/lib/ssm/tests/rbuff_test.c index 58cb39c3..48e5a714 100644 --- a/src/lib/ssm/tests/rbuff_test.c +++ b/src/lib/ssm/tests/rbuff_test.c @@ -206,10 +206,10 @@ static int test_ssm_rbuff_fill_drain(void) return TEST_RC_FAIL; } -static int test_ssm_rbuff_acl(void) +static int test_ssm_rbuff_flags(void) { struct ssm_rbuff * rb; - uint32_t acl; + uint32_t flags; TEST_START(); @@ -219,16 +219,16 @@ static int test_ssm_rbuff_acl(void) goto fail; } - acl = ssm_rbuff_get_acl(rb); - if (acl != ACL_RDWR) { - printf("Expected ACL_RDWR, got %u.\n", acl); + flags = ssm_rbuff_get_flags(rb); + if (flags != RB_RDWR) { + printf("Expected RB_RDWR, got %u.\n", flags); goto fail_rb; } - ssm_rbuff_set_acl(rb, ACL_RDONLY); - acl = ssm_rbuff_get_acl(rb); - if (acl != ACL_RDONLY) { - printf("Expected ACL_RDONLY, got %u.\n", acl); + ssm_rbuff_clr_bits(rb, RB_WR); + flags = ssm_rbuff_get_flags(rb); + if (flags != RB_RD) { + printf("Expected RB_RD, got %u.\n", flags); goto fail_rb; } @@ -237,7 +237,7 @@ static int test_ssm_rbuff_acl(void) goto fail_rb; } - ssm_rbuff_set_acl(rb, ACL_FLOWDOWN); + ssm_rbuff_set_bits(rb, RB_FLOWDOWN); if (ssm_rbuff_write(rb, 1) != -EFLOWDOWN) { printf("Expected -EFLOWDOWN on FLOWDOWN.\n"); goto fail_rb; @@ -553,7 +553,7 @@ static int test_ssm_rbuff_blocking_flowdown(void) clock_gettime(PTHREAD_COND_CLOCK, &now); ts_add(&now, &interval, &abs_timeout); - ssm_rbuff_set_acl(rb, ACL_FLOWDOWN); + ssm_rbuff_set_bits(rb, RB_FLOWDOWN); ret = ssm_rbuff_read_b(rb, &abs_timeout); if (ret != -EFLOWDOWN) { @@ -561,7 +561,7 @@ static int test_ssm_rbuff_blocking_flowdown(void) goto fail_rb; } - ssm_rbuff_set_acl(rb, ACL_RDWR); + ssm_rbuff_clr_bits(rb, RB_FLOWDOWN); for (i = 0; i < SSM_RBUFF_SIZE - 1; ++i) { if (ssm_rbuff_write(rb, i) < 0) { @@ -573,7 +573,7 @@ static int test_ssm_rbuff_blocking_flowdown(void) clock_gettime(PTHREAD_COND_CLOCK, &now); ts_add(&now, &interval, &abs_timeout); - ssm_rbuff_set_acl(rb, ACL_FLOWDOWN); + ssm_rbuff_set_bits(rb, RB_FLOWDOWN); ret = ssm_rbuff_write_b(rb, 999, &abs_timeout); if (ret != -EFLOWDOWN) { @@ -581,7 +581,7 @@ static int test_ssm_rbuff_blocking_flowdown(void) goto fail_rb; } - ssm_rbuff_set_acl(rb, ACL_RDWR); + ssm_rbuff_clr_bits(rb, RB_FLOWDOWN); while (ssm_rbuff_read(rb) >= 0) ; @@ -664,7 +664,7 @@ int rbuff_test(int argc, ret |= test_ssm_rbuff_write_read(); ret |= test_ssm_rbuff_read_empty(); ret |= test_ssm_rbuff_fill_drain(); - ret |= test_ssm_rbuff_acl(); + ret |= test_ssm_rbuff_flags(); ret |= test_ssm_rbuff_open_close(); ret |= test_ssm_rbuff_threaded(); ret |= test_ssm_rbuff_blocking(); -- cgit v1.2.3