lkml.org 
[lkml]   [2012]   [Aug]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 15/25] KEYS: Provide PGP key description autogeneration
Date
Provide a facility to autogenerate the name of PGP keys from the contents of
the payload. If add_key() is given a blank description, a description is
constructed from the last user ID packet in the payload data plus the last 8
hex digits of the key ID. For instance:

keyctl padd crypto "" @s </tmp/key.pub

might create a key with a constructed description that can be seen in
/proc/keys:

2f674b96 I--Q--- 1 perm 39390000 0 0 crypto Sample kernel key 31f0ae93: PGP.RSA 31f0ae93 []
Signed-off-by: David Howells <dhowells@redhat.com>
---
security/keys/crypto/pgp_public_key.c | 64 +++++++++++++++++++++++++++------
1 file changed, 53 insertions(+), 11 deletions(-)

diff --git a/security/keys/crypto/pgp_public_key.c b/security/keys/crypto/pgp_public_key.c
index c260e02..2347ecd 100644
--- a/security/keys/crypto/pgp_public_key.c
+++ b/security/keys/crypto/pgp_public_key.c
@@ -52,6 +52,9 @@ struct pgp_key_data_parse_context {
struct crypto_key_subtype *subtype;
char *fingerprint;
void *payload;
+ const char *user_id;
+ size_t user_id_len;
+ size_t fingerprint_len;
};

/*
@@ -166,6 +169,7 @@ static int pgp_generate_fingerprint(struct pgp_key_data_parse_context *ctx,
if (ret < 0)
goto cleanup_raw_fingerprint;

+ ctx->fingerprint_len = digest_size * 2;
fingerprint = kmalloc(digest_size * 2 + 1, GFP_KERNEL);
if (!fingerprint)
goto cleanup_raw_fingerprint;
@@ -212,6 +216,13 @@ static int pgp_process_public_key(struct pgp_parse_context *context,

kenter(",%u,%u,,%zu", type, headerlen, datalen);

+ if (type == PGP_PKT_USER_ID) {
+ ctx->user_id = data;
+ ctx->user_id_len = datalen;
+ kleave(" = 0 [user ID]");
+ return 0;
+ }
+
if (ctx->subtype) {
kleave(" = -ENOKEY [already]");
return -EBADMSG;
@@ -297,21 +308,44 @@ static int pgp_key_preparse(struct key_preparsed_payload *prep)

kenter("");

+ memset(&ctx, 0, sizeof(ctx));
ctx.pgp.types_of_interest =
- (1 << PGP_PKT_PUBLIC_KEY) | (1 << PGP_PKT_PUBLIC_SUBKEY);
+ (1 << PGP_PKT_PUBLIC_KEY) | (1 << PGP_PKT_PUBLIC_SUBKEY) |
+ (1 << PGP_PKT_USER_ID);
ctx.pgp.process_packet = pgp_process_public_key;
- ctx.subtype = NULL;
- ctx.fingerprint = NULL;
- ctx.payload = NULL;

ret = pgp_parse_packets(prep->data, prep->datalen, &ctx.pgp);
- if (ret < 0) {
- if (ctx.payload)
- ctx.subtype->destroy(ctx.payload);
- if (ctx.subtype)
- module_put(ctx.subtype->owner);
- kfree(ctx.fingerprint);
- return ret;
+ if (ret < 0)
+ goto error;
+
+ if (ctx.user_id && ctx.user_id_len > 0) {
+ /* Propose a description for the key (user ID without the comment) */
+ size_t ulen = ctx.user_id_len, flen = ctx.fingerprint_len;
+ const char *p;
+
+ p = memchr(ctx.user_id, '(', ulen);
+ if (p) {
+ /* Remove the comment */
+ do {
+ p--;
+ } while (*p == ' ' && p > ctx.user_id);
+ if (*p != ' ')
+ p++;
+ ulen = p - ctx.user_id;
+ }
+
+ if (ulen > 255 - 9)
+ ulen = 255 - 9;
+ prep->description = kmalloc(ulen + 1 + 8 + 1, GFP_KERNEL);
+ ret = -ENOMEM;
+ if (!prep->description)
+ goto error;
+ memcpy(prep->description, ctx.user_id, ulen);
+ prep->description[ulen] = ' ';
+ memcpy(prep->description + ulen + 1,
+ ctx.fingerprint + flen - 8, 8);
+ prep->description[ulen + 9] = 0;
+ pr_debug("desc '%s'\n", prep->description);
}

prep->type_data[0] = ctx.subtype;
@@ -319,6 +353,14 @@ static int pgp_key_preparse(struct key_preparsed_payload *prep)
prep->payload = ctx.payload;
prep->quotalen = prep->datalen;
return 0;
+
+error:
+ if (ctx.payload)
+ ctx.subtype->destroy(ctx.payload);
+ if (ctx.subtype)
+ module_put(ctx.subtype->owner);
+ kfree(ctx.fingerprint);
+ return ret;
}

static struct crypto_key_parser pgp_key_parser = {


\
 
 \ /
  Last update: 2012-08-16 04:44    [from the cache]
©2003-2011 Jasper Spaans