added anonymous sender key (-A) support

This commit is contained in:
git@daemon.de
2014-08-11 15:45:47 +02:00
parent e022a9e842
commit 298e6b1469
11 changed files with 131 additions and 69 deletions

View File

@@ -161,19 +161,15 @@ byte *pcp_box_decrypt(PCPCTX *ptx, pcp_key_t *secret, pcp_pubkey_t *pub,
return NULL;
}
size_t pcp_decrypt_stream(PCPCTX *ptx, Pcpstream *in, Pcpstream* out, pcp_key_t *s, byte *symkey, int verify) {
size_t pcp_decrypt_stream(PCPCTX *ptx, Pcpstream *in, Pcpstream* out, pcp_key_t *s, byte *symkey, int verify, int anon) {
pcp_pubkey_t *cur = NULL;
byte *reccipher = NULL;
int recmatch, self;
uint32_t lenrec;
byte head[1];
size_t cur_bufsize, rec_size, nrec;
byte *rec_buf = NULL;
#ifdef PCP_ASYM_ADD_SENDER_PUB
byte *senderpub;
#endif
pcp_pubkey_t *senderpub = NULL; /* anon only */
nrec = recmatch = self = 0;
@@ -194,6 +190,10 @@ size_t pcp_decrypt_stream(PCPCTX *ptx, Pcpstream *in, Pcpstream* out, pcp_key_t
goto errdef1;
}
}
else if(head[0] == PCP_ASYM_CIPHER_ANON) {
self = 0;
anon = 1;
}
else if(head[0] == PCP_ASYM_CIPHER) {
self = 0;
}
@@ -213,14 +213,15 @@ size_t pcp_decrypt_stream(PCPCTX *ptx, Pcpstream *in, Pcpstream* out, pcp_key_t
return pcp_decrypt_stream_sym(ptx, in, out, symkey, NULL);
}
#ifdef PCP_ASYM_ADD_SENDER_PUB
/* step 2, sender's pubkey */
cur_bufsize = ps_read(in, &in_buf, crypto_box_PUBLICKEYBYTES);
if(cur_bufsize != crypto_box_PUBLICKEYBYTES && !ps_end(in) && !ps_err(in)) {
fatal(ptx, "Error: input file doesn't contain senders public key\n");
goto errdef1;
if(anon) {
/* step 2, sender's pubkey */
senderpub = ucmalloc(sizeof(pcp_pubkey_t));
cur_bufsize = ps_read(in, senderpub->pub, crypto_box_PUBLICKEYBYTES);
if(cur_bufsize != crypto_box_PUBLICKEYBYTES && !ps_end(in) && !ps_err(in)) {
fatal(ptx, "Error: input file doesn't contain senders public key\n");
goto errdef1;
}
}
#endif
/* step 3, check len recipients */
cur_bufsize = ps_read(in, &lenrec, 4); /* fread(&lenrec, 1, 4, in); */
@@ -247,17 +248,36 @@ size_t pcp_decrypt_stream(PCPCTX *ptx, Pcpstream *in, Pcpstream* out, pcp_key_t
}
recmatch = 0;
pcphash_iteratepub(ptx, cur) {
if(anon) {
/* anonymous sender */
byte *recipient;
recipient = pcp_box_decrypt(ptx, s, cur, rec_buf, PCP_ASYM_RECIPIENT_SIZE, &rec_size);
recipient = pcp_box_decrypt(ptx, s, senderpub, rec_buf, PCP_ASYM_RECIPIENT_SIZE, &rec_size);
if(recipient != NULL && rec_size == crypto_secretbox_KEYBYTES) {
/* found a match */
recmatch = 1;
symkey = ucmalloc(crypto_secretbox_KEYBYTES);
memcpy(symkey, recipient, crypto_secretbox_KEYBYTES);
free(recipient);
ucfree(senderpub, sizeof(pcp_pubkey_t));
break;
}
free(recipient);
}
else {
/* dig through our list of known public keys for a match */
pcphash_iteratepub(ptx, cur) {
byte *recipient;
recipient = pcp_box_decrypt(ptx, s, cur, rec_buf, PCP_ASYM_RECIPIENT_SIZE, &rec_size);
if(recipient != NULL && rec_size == crypto_secretbox_KEYBYTES) {
/* found a match */
recmatch = 1;
symkey = ucmalloc(crypto_secretbox_KEYBYTES);
memcpy(symkey, recipient, crypto_secretbox_KEYBYTES);
free(recipient);
break;
}
free(recipient);
}
}
if(verify) {
size_t R = nrec * (PCP_ASYM_RECIPIENT_SIZE);
@@ -290,7 +310,7 @@ size_t pcp_decrypt_stream(PCPCTX *ptx, Pcpstream *in, Pcpstream* out, pcp_key_t
return 0;
}
size_t pcp_encrypt_stream(PCPCTX *ptx, Pcpstream *in, Pcpstream *out, pcp_key_t *s, pcp_pubkey_t *p, int sign) {
size_t pcp_encrypt_stream(PCPCTX *ptx, Pcpstream *in, Pcpstream *out, pcp_key_t *s, pcp_pubkey_t *p, int sign, int anon) {
byte *symkey;
int recipient_count;
byte *recipients_cipher;
@@ -336,24 +356,25 @@ size_t pcp_encrypt_stream(PCPCTX *ptx, Pcpstream *in, Pcpstream *out, pcp_key_t
/* step 1, file header */
if(sign)
head[0] = PCP_ASYM_CIPHER_SIG;
else if(anon)
head[0] = PCP_ASYM_CIPHER_ANON;
else
head[0] = PCP_ASYM_CIPHER;
ps_write(out, head, 1);
/* fwrite(head, 1, 1, out); */
/* fprintf(stderr, "D: header - 1\n"); */
if(ps_err(out) != 0) {
fatal(ptx, "Failed to write encrypted output!\n");
goto errec1;
}
#ifdef PCP_ASYM_ADD_SENDER_PUB
/* step 2, sender's pubkey */
ps_write(out, s->pub, crypto_box_PUBLICKEYBYTES);
/*fwrite(s->pub, crypto_box_PUBLICKEYBYTES, 1, out); */
/* fprintf(stderr, "D: sender pub - %d\n", crypto_box_PUBLICKEYBYTES); */
if(ps_err(out) != 0)
goto errec1;
#endif
if(anon) {
/* step 2, sender's pubkey */
ps_write(out, s->pub, crypto_box_PUBLICKEYBYTES);
/*fwrite(s->pub, crypto_box_PUBLICKEYBYTES, 1, out); */
/* fprintf(stderr, "D: sender pub - %d\n", crypto_box_PUBLICKEYBYTES); */
if(ps_err(out) != 0)
goto errec1;
}
/* step 3, len recipients, big endian */
lenrec = recipient_count;