In 06c92dafb8 (Makefile: allow specifying a SHA-1 for non-cryptographic
uses, 2024-09-26), support for unsafe SHA-1 is added. Add the unsafe
SHA-1 build info to `git version --build-info` and update corresponding
documentation.
Signed-off-by: Justin Tobler <jltobler@xxxxxxxxx>
---
Documentation/git-version.adoc | 3 +++
hash.h | 3 +++
help.c | 5 +++++
3 files changed, 11 insertions(+)
diff --git a/Documentation/git-version.adoc b/Documentation/git-version.adoc
index f06758a7cf..753794988c 100644
--- a/Documentation/git-version.adoc
+++ b/Documentation/git-version.adoc
@@ -25,6 +25,9 @@ OPTIONS
+
Note that the SHA1 options `SHA1_APPLE`, `SHA1_OPENSSL`, and `SHA1_BLK` do not
have collision detection.
++
+If built to use a faster SHA-1 implementation for non-cryptographic purposes,
+that implementation is denoted as "non-crypto-SHA-1".
GIT
---
diff --git a/hash.h b/hash.h
index 51cd0ec7b6..72334d3506 100644
--- a/hash.h
+++ b/hash.h
@@ -20,12 +20,14 @@
#endif
#if defined(SHA1_APPLE_UNSAFE)
+# define SHA1_UNSAFE_BACKEND "SHA1_APPLE_UNSAFE"
# include <CommonCrypto/CommonDigest.h>
# define platform_SHA_CTX_unsafe CC_SHA1_CTX
# define platform_SHA1_Init_unsafe CC_SHA1_Init
# define platform_SHA1_Update_unsafe CC_SHA1_Update
# define platform_SHA1_Final_unsafe CC_SHA1_Final
#elif defined(SHA1_OPENSSL_UNSAFE)
+# define SHA1_UNSAFE_BACKEND "SHA1_OPENSSL_UNSAFE"
# include <openssl/sha.h>
# if defined(OPENSSL_API_LEVEL) && OPENSSL_API_LEVEL >= 3
# define SHA1_NEEDS_CLONE_HELPER_UNSAFE
@@ -42,6 +44,7 @@
# define platform_SHA1_Final_unsafe SHA1_Final
# endif
#elif defined(SHA1_BLK_UNSAFE)
+# define SHA1_UNSAFE_BACKEND "SHA1_BLK_UNSAFE"
# include "block-sha1/sha1.h"
# define platform_SHA_CTX_unsafe blk_SHA_CTX
# define platform_SHA1_Init_unsafe blk_SHA1_Init
diff --git a/help.c b/help.c
index 3aebfb3681..1238a962b0 100644
--- a/help.c
+++ b/help.c
@@ -772,6 +772,11 @@ char *help_unknown_cmd(const char *cmd)
static void get_sha_impl(struct strbuf *buf)
{
strbuf_addf(buf, "SHA-1: %s\n", SHA1_BACKEND);
+
+#if defined(SHA1_UNSAFE_BACKEND)
+ strbuf_addf(buf, "non-crypto-SHA-1: %s\n", SHA1_UNSAFE_BACKEND);
+#endif
+
strbuf_addf(buf, "SHA-256: %s\n", SHA256_BACKEND);
}
--
2.49.0
