From: Guan-Chun Wu <409411716@gms.tku.edu.tw> Date: Fri, 14 Nov 2025 06:02:40 +0000 (+0800) Subject: ceph: replace local base64 helpers with lib/base64 X-Git-Tag: v6.19-rc1~70^2~66 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b1b72ac25f89125d91ef3abd257c3b88ec169962;p=thirdparty%2Flinux.git ceph: replace local base64 helpers with lib/base64 Remove the ceph_base64_encode() and ceph_base64_decode() functions and replace their usage with the generic base64_encode() and base64_decode() helpers from lib/base64. This eliminates the custom implementation in Ceph, reduces code duplication, and relies on the shared Base64 code in lib. The helpers preserve RFC 3501-compliant Base64 encoding without padding, so there are no functional changes. This change also improves performance: encoding is about 2.7x faster and decoding achieves 43-52x speedups compared to the previous local implementation. Link: https://lkml.kernel.org/r/20251114060240.89965-1-409411716@gms.tku.edu.tw Signed-off-by: Guan-Chun Wu <409411716@gms.tku.edu.tw> Reviewed-by: Kuan-Wei Chiu Reviewed-by: Viacheslav Dubeyko Cc: Keith Busch Cc: Jens Axboe Cc: Christoph Hellwig Cc: Sagi Grimberg Cc: Xiubo Li Cc: Ilya Dryomov Cc: Eric Biggers Cc: "Theodore Y. Ts'o" Cc: Jaegeuk Kim Cc: David Laight Cc: Yu-Sheng Huang Signed-off-by: Andrew Morton --- diff --git a/fs/ceph/crypto.c b/fs/ceph/crypto.c index 7026e794813ca..b6016dcffbb6c 100644 --- a/fs/ceph/crypto.c +++ b/fs/ceph/crypto.c @@ -15,59 +15,6 @@ #include "mds_client.h" #include "crypto.h" -/* - * The base64url encoding used by fscrypt includes the '_' character, which may - * cause problems in snapshot names (which can not start with '_'). Thus, we - * used the base64 encoding defined for IMAP mailbox names (RFC 3501) instead, - * which replaces '-' and '_' by '+' and ','. - */ -static const char base64_table[65] = - "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+,"; - -int ceph_base64_encode(const u8 *src, int srclen, char *dst) -{ - u32 ac = 0; - int bits = 0; - int i; - char *cp = dst; - - for (i = 0; i < srclen; i++) { - ac = (ac << 8) | src[i]; - bits += 8; - do { - bits -= 6; - *cp++ = base64_table[(ac >> bits) & 0x3f]; - } while (bits >= 6); - } - if (bits) - *cp++ = base64_table[(ac << (6 - bits)) & 0x3f]; - return cp - dst; -} - -int ceph_base64_decode(const char *src, int srclen, u8 *dst) -{ - u32 ac = 0; - int bits = 0; - int i; - u8 *bp = dst; - - for (i = 0; i < srclen; i++) { - const char *p = strchr(base64_table, src[i]); - - if (p == NULL || src[i] == 0) - return -1; - ac = (ac << 6) | (p - base64_table); - bits += 6; - if (bits >= 8) { - bits -= 8; - *bp++ = (u8)(ac >> bits); - } - } - if (ac & ((1 << bits) - 1)) - return -1; - return bp - dst; -} - static int ceph_crypt_get_context(struct inode *inode, void *ctx, size_t len) { struct ceph_inode_info *ci = ceph_inode(inode); @@ -318,7 +265,7 @@ int ceph_encode_encrypted_dname(struct inode *parent, char *buf, int elen) } /* base64 encode the encrypted name */ - elen = ceph_base64_encode(cryptbuf, len, p); + elen = base64_encode(cryptbuf, len, p, false, BASE64_IMAP); doutc(cl, "base64-encoded ciphertext name = %.*s\n", elen, p); /* To understand the 240 limit, see CEPH_NOHASH_NAME_MAX comments */ @@ -412,7 +359,8 @@ int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname, tname = &_tname; } - declen = ceph_base64_decode(name, name_len, tname->name); + declen = base64_decode(name, name_len, + tname->name, false, BASE64_IMAP); if (declen <= 0) { ret = -EIO; goto out; @@ -426,7 +374,7 @@ int ceph_fname_to_usr(const struct ceph_fname *fname, struct fscrypt_str *tname, ret = fscrypt_fname_disk_to_usr(dir, 0, 0, &iname, oname); if (!ret && (dir != fname->dir)) { - char tmp_buf[CEPH_BASE64_CHARS(NAME_MAX)]; + char tmp_buf[BASE64_CHARS(NAME_MAX)]; name_len = snprintf(tmp_buf, sizeof(tmp_buf), "_%.*s_%ld", oname->len, oname->name, dir->i_ino); diff --git a/fs/ceph/crypto.h b/fs/ceph/crypto.h index 23612b2e9837d..b748e2060bc9b 100644 --- a/fs/ceph/crypto.h +++ b/fs/ceph/crypto.h @@ -8,6 +8,7 @@ #include #include +#include #define CEPH_FSCRYPT_BLOCK_SHIFT 12 #define CEPH_FSCRYPT_BLOCK_SIZE (_AC(1, UL) << CEPH_FSCRYPT_BLOCK_SHIFT) @@ -89,11 +90,6 @@ static inline u32 ceph_fscrypt_auth_len(struct ceph_fscrypt_auth *fa) */ #define CEPH_NOHASH_NAME_MAX (180 - SHA256_DIGEST_SIZE) -#define CEPH_BASE64_CHARS(nbytes) DIV_ROUND_UP((nbytes) * 4, 3) - -int ceph_base64_encode(const u8 *src, int srclen, char *dst); -int ceph_base64_decode(const char *src, int srclen, u8 *dst); - void ceph_fscrypt_set_ops(struct super_block *sb); void ceph_fscrypt_free_dummy_policy(struct ceph_fs_client *fsc); diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c index d18c0eaef9b7e..0fa7c7777242e 100644 --- a/fs/ceph/dir.c +++ b/fs/ceph/dir.c @@ -998,13 +998,14 @@ static int prep_encrypted_symlink_target(struct ceph_mds_request *req, if (err) goto out; - req->r_path2 = kmalloc(CEPH_BASE64_CHARS(osd_link.len) + 1, GFP_KERNEL); + req->r_path2 = kmalloc(BASE64_CHARS(osd_link.len) + 1, GFP_KERNEL); if (!req->r_path2) { err = -ENOMEM; goto out; } - len = ceph_base64_encode(osd_link.name, osd_link.len, req->r_path2); + len = base64_encode(osd_link.name, osd_link.len, + req->r_path2, false, BASE64_IMAP); req->r_path2[len] = '\0'; out: fscrypt_fname_free_buffer(&osd_link); diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index a6e260d9e4205..b691343cb7f18 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -958,7 +958,7 @@ static int decode_encrypted_symlink(struct ceph_mds_client *mdsc, if (!sym) return -ENOMEM; - declen = ceph_base64_decode(encsym, enclen, sym); + declen = base64_decode(encsym, enclen, sym, false, BASE64_IMAP); if (declen < 0) { pr_err_client(cl, "can't decode symlink (%d). Content: %.*s\n",