[PATCH 2/2] receive-pack: use find_commit_header() in check_nonce()
- From
René Scharfe <l.s.r@web.de>
- Date
- Feb 9, 2024, 20:41 UTC
- Message-ID
- <8b350cae-2180-4ac7-a911-d40043576445@web.de>
- In-Reply-To
- <ff0db7e3-abce-44ea-a1e3-16e1fdaf4c75@web.de>
Use the public function find_commit_header() and remove find_header(), as it becomes unused. This is safe and appropriate because we pass the NUL-terminated payload buffer to check_nonce() instead of its start and length. The underlying strbuf push_cert cannot contain NULs, as it is built using strbuf_addstr(), only.
We no longer need to call strlen(), as find_commit_header() returns the length of nonce already.
Signed-off-by: René Scharfe <l.s.r@web.de> --- Formatted with -U5 for easier review. Removing find_header_mem(), which basically becomes unused, left as an exercise for the reader. ;)
builtin/receive-pack.c | 25 +++++-------------------- 1 file changed, 5 insertions(+), 20 deletions(-)
diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index 8ebb3a872f..dbee508775 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -591,25 +591,10 @@ static char *prepare_push_cert_nonce(const char *path, timestamp_t stamp) /* RFC 2104 5. HMAC-SHA1 or HMAC-SHA256 */ strbuf_addf(&buf, "%"PRItime"-%.*s", stamp, (int)the_hash_algo->hexsz, hash_to_hex(hash)); return strbuf_detach(&buf, NULL); } -static char *find_header(const char *msg, size_t len, const char *key, - const char **next_line) -{ - size_t out_len; - const char *val = find_header_mem(msg, len, key, &out_len); - - if (!val) - return NULL; - - if (next_line) - *next_line = val + out_len + 1; - - return xmemdupz(val, out_len); -} - /* * Return zero if a and b are equal up to n bytes and nonzero if they are not. * This operation is guaranteed to run in constant time to avoid leaking data. */ static int constant_memequal(const char *a, const char *b, size_t n) @@ -620,17 +605,18 @@ static int constant_memequal(const char *a, const char *b, size_t n) for (i = 0; i < n; i++) res |= a[i] ^ b[i]; return res; } -static const char *check_nonce(const char *buf, size_t len) +static const char *check_nonce(const char *buf) { - char *nonce = find_header(buf, len, "nonce", NULL); + size_t noncelen; + const char *found = find_commit_header(buf, "nonce", &noncelen); + char *nonce = found ? xmemdupz(found, noncelen) : NULL; timestamp_t stamp, ostamp; char *bohmac, *expect = NULL; const char *retval = NONCE_BAD; - size_t noncelen; if (!nonce) { retval = NONCE_MISSING; goto leave; } else if (!push_cert_nonce) { @@ -668,11 +654,10 @@ static const char *check_nonce(const char *buf, size_t len) if (bohmac == nonce || bohmac[0] != '-') { retval = NONCE_BAD; goto leave; } - noncelen = strlen(nonce); expect = prepare_push_cert_nonce(service_dir, stamp); if (noncelen != strlen(expect)) { /* This is not even the right size. */ retval = NONCE_BAD; goto leave; @@ -765,11 +750,11 @@ static void prepare_push_cert_sha1(struct child_process *proc) sigcheck.payload = xmemdupz(push_cert.buf, bogs); sigcheck.payload_len = bogs; check_signature(&sigcheck, push_cert.buf + bogs, push_cert.len - bogs); - nonce_status = check_nonce(push_cert.buf, bogs); + nonce_status = check_nonce(sigcheck.payload); } if (!is_null_oid(&push_cert_oid)) { strvec_pushf(&proc->env, "GIT_PUSH_CERT=%s", oid_to_hex(&push_cert_oid)); strvec_pushf(&proc->env, "GIT_PUSH_CERT_SIGNER=%s", -- 2.43.0