From af664fc9023e69d1a90800c0f815c296bf727e18 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Sun, 15 Jan 2023 12:22:30 -0500 Subject: [PATCH] SUNRPC: Add new subkey length fields The aes256-cts-hmac-sha384-192 enctype specifies the length of its checksum and integrity subkeys as 192 bits, but the length of its encryption subkey (Ke) as 256 bits. Add new fields to struct gss_krb5_enctype that specify the key lengths individually, and where needed, use the correct new field instead of ->keylength. Tested-by: Scott Mayhew Reviewed-by: Simo Sorce Signed-off-by: Chuck Lever --- include/linux/sunrpc/gss_krb5.h | 14 ++++++++++++-- net/sunrpc/auth_gss/gss_krb5_mech.c | 20 ++++++++++++++------ 2 files changed, 26 insertions(+), 8 deletions(-) diff --git a/include/linux/sunrpc/gss_krb5.h b/include/linux/sunrpc/gss_krb5.h index 04addef..3e97d2a 100644 --- a/include/linux/sunrpc/gss_krb5.h +++ b/include/linux/sunrpc/gss_krb5.h @@ -42,10 +42,16 @@ #include #include +/* + * The RFCs often specify payload lengths in bits. This helper + * converts a specified bit-length to the number of octets/bytes. + */ +#define BITS2OCTETS(x) ((x) / 8) + /* Length of constant used in key derivation */ #define GSS_KRB5_K5CLENGTH (5) -/* Maximum key length (in bytes) for the supported crypto algorithms*/ +/* Maximum key length (in bytes) for the supported crypto algorithms */ #define GSS_KRB5_MAX_KEYLEN (32) /* Maximum checksum function output for the supported crypto algorithms */ @@ -68,7 +74,11 @@ struct gss_krb5_enctype { const u32 cksumlength; /* checksum length */ const u32 keyed_cksum; /* is it a keyed cksum? */ const u32 keybytes; /* raw key len, in bytes */ - const u32 keylength; /* final key len, in bytes */ + const u32 keylength; /* protocol key length, in octets */ + const u32 Kc_length; /* checksum subkey length, in octets */ + const u32 Ke_length; /* encryption subkey length, in octets */ + const u32 Ki_length; /* integrity subkey length, in octets */ + int (*import_ctx)(struct krb5_ctx *ctx, gfp_t gfp_mask); int (*derive_key)(const struct gss_krb5_enctype *gk5e, const struct xdr_netobj *in, diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c index 45f461f..ec3cca8 100644 --- a/net/sunrpc/auth_gss/gss_krb5_mech.c +++ b/net/sunrpc/auth_gss/gss_krb5_mech.c @@ -108,8 +108,11 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = { .signalg = -1, .sealalg = -1, .keybytes = 16, - .keylength = 16, - .cksumlength = 12, + .keylength = BITS2OCTETS(128), + .Kc_length = BITS2OCTETS(128), + .Ke_length = BITS2OCTETS(128), + .Ki_length = BITS2OCTETS(128), + .cksumlength = BITS2OCTETS(96), .keyed_cksum = 1, }, /* @@ -135,8 +138,11 @@ static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = { .signalg = -1, .sealalg = -1, .keybytes = 32, - .keylength = 32, - .cksumlength = 12, + .keylength = BITS2OCTETS(256), + .Kc_length = BITS2OCTETS(256), + .Ke_length = BITS2OCTETS(256), + .Ki_length = BITS2OCTETS(256), + .cksumlength = BITS2OCTETS(96), .keyed_cksum = 1, }, #endif @@ -423,12 +429,12 @@ gss_krb5_import_ctx_v2(struct krb5_ctx *ctx, gfp_t gfp_mask) struct xdr_netobj keyout; int ret = -EINVAL; - keyout.data = kmalloc(ctx->gk5e->keylength, gfp_mask); + keyout.data = kmalloc(GSS_KRB5_MAX_KEYLEN, gfp_mask); if (!keyout.data) return -ENOMEM; - keyout.len = ctx->gk5e->keylength; /* initiator seal encryption */ + keyout.len = ctx->gk5e->Ke_length; if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION, gfp_mask)) goto out; @@ -461,6 +467,7 @@ gss_krb5_import_ctx_v2(struct krb5_ctx *ctx, gfp_t gfp_mask) } /* initiator sign checksum */ + keyout.len = ctx->gk5e->Kc_length; if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM, gfp_mask)) goto out_free; @@ -477,6 +484,7 @@ gss_krb5_import_ctx_v2(struct krb5_ctx *ctx, gfp_t gfp_mask) goto out_free; /* initiator seal integrity */ + keyout.len = ctx->gk5e->Ki_length; if (krb5_derive_key(ctx, &keyin, &keyout, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY, gfp_mask)) goto out_free; -- 2.7.4