serval-dna/rhizome_bundle.c

/*
Serval DNA - Rhizome manifest operations
Copyright (C) 2010 Paul Gardner-Stephen
Copyright (C) 2013-2014 Serval Project Inc.
 
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
 
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
 
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
*/

#include <stdlib.h>
#include <assert.h>
#include <sys/uio.h>
#include "lang.h" // for FALLTHROUGH
#include "serval.h"
#include "conf.h"
#include "crypto.h"
#include "rhizome.h"
#include "str.h"
#include "numeric_str.h"
#include "mem.h"
#include "keyring.h"
#include "dataformats.h"
#include "debug.h"

static const char *rhizome_manifest_get(const rhizome_manifest *m, const char *var)
{
  unsigned i;
  for (i = 0; i < m->var_count; ++i)
    if (strcmp(m->vars[i], var) == 0)
      return m->values[i];
  return NULL;
}

/* Remove the field with the given label from the manifest
 *
 * @author Andrew Bettison <andrew@servalproject.com>
 */
static int _rhizome_manifest_del(struct __sourceloc __whence, rhizome_manifest *m, const char *var)
{
  DEBUGF(rhizome_manifest, "DEL manifest %p %s", m, var);
  int ret = 0;
  unsigned i;
  for (i = 0; i < m->var_count; ++i)
    if (strcmp(m->vars[i], var) == 0) {
      free((char *) m->vars[i]);
      free((char *) m->values[i]);
      --m->var_count;
      ret = 1;
      break;
    }
  for (; i < m->var_count; ++i) {
    m->vars[i] = m->vars[i + 1];
    m->values[i] = m->values[i + 1];
  }
  return ret;
}

#define rhizome_manifest_set(m,var,value) _rhizome_manifest_set(__WHENCE__, (m), (var), (value))
#define rhizome_manifest_set_ui64(m,var,value) _rhizome_manifest_set_ui64(__WHENCE__, (m), (var), (value))
#define rhizome_manifest_del(m,var) _rhizome_manifest_del(__WHENCE__, (m), (var))

static const char *_rhizome_manifest_set(struct __sourceloc __whence, rhizome_manifest *m, const char *var, const char *value)
{
  DEBUGF(rhizome_manifest, "SET manifest %p %s = %s", m, var, alloca_str_toprint(value));
  unsigned i;
  for(i=0;i<m->var_count;i++)
    if (strcmp(m->vars[i],var) == 0) {
      const char *ret = str_edup(value);
      if (ret == NULL)
	return NULL;
      free((char *)m->values[i]);
      m->values[i] = ret;
      return ret;
    }
  if (m->var_count >= NELS(m->vars)) {
    WHY("no more manifest vars");
    return NULL;
  }
  if ((m->vars[m->var_count] = str_edup(var)) == NULL)
    return NULL;
  const char *ret = m->values[m->var_count] = str_edup(value);
  if (ret == NULL) {
    free((char *)m->vars[i]);
    m->vars[i] = NULL;
    return NULL;
  }
  m->var_count++;
  return ret;
}

static const char *_rhizome_manifest_set_ui64(struct __sourceloc __whence, rhizome_manifest *m, char *var, uint64_t value)
{
  char str[50];
  snprintf(str, sizeof str, "%" PRIu64, value);
  return rhizome_manifest_set(m, var, str);
}

void _rhizome_manifest_set_id(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_bid_t *bidp)
{
  if (bidp) {
    if (m->has_id && (bidp == &m->keypair.public_key || cmp_rhizome_bid_t(&m->keypair.public_key, bidp) == 0))
      return; // unchanged
    const char *v = rhizome_manifest_set(m, "id", alloca_tohex_rhizome_bid_t(*bidp));
    assert(v); // TODO: remove known manifest fields from vars[]
    m->keypair.public_key = *bidp;
    m->has_id = 1;
  } else if (m->has_id) {
    bzero(&m->keypair.public_key, sizeof m->keypair.public_key); // not strictly necessary but aids debugging
    m->has_id = 0;
  } else
    return; // unchanged
  // The BID has changed.
  m->finalised = 0;
  // Any existing secret key and bundle key are no longer valid.
  if (m->haveSecret) {
    m->haveSecret = SECRET_UNKNOWN;
    bzero(m->keypair.private_key.binary, sizeof m->keypair.private_key.binary); // not strictly necessary but aids debugging
  }
  if (m->has_bundle_key) {
    m->has_bundle_key = 0;
    m->bundle_key = RHIZOME_BK_NONE; // not strictly necessary but aids debugging
  }
  // Any authenticated author is no longer authenticated, but is still known to be in the keyring.
  if (m->authorship == AUTHOR_AUTHENTIC)
    m->authorship = AUTHOR_LOCAL;
}

void _rhizome_manifest_set_version(struct __sourceloc __whence, rhizome_manifest *m, uint64_t version)
{
  if (version) {
    const char *v = rhizome_manifest_set_ui64(m, "version", version);
    assert(v); // TODO: remove known manifest fields from vars[]
  } else
    rhizome_manifest_del(m, "version");
  m->version = version;
  m->finalised = 0;
}

void _rhizome_manifest_del_version(struct __sourceloc __whence, rhizome_manifest *m)
{
  _rhizome_manifest_set_version(__whence, m, 0);
}

void _rhizome_manifest_set_filesize(struct __sourceloc __whence, rhizome_manifest *m, uint64_t size)
{
  if (size == RHIZOME_SIZE_UNSET) {
    rhizome_manifest_del(m, "filesize");
  } else {
    const char *v = rhizome_manifest_set_ui64(m, "filesize", size);
    assert(v); // TODO: remove known manifest fields from vars[]
  }
  m->filesize = size;
  m->finalised = 0;
}

void _rhizome_manifest_del_filesize(struct __sourceloc __whence, rhizome_manifest *m)
{
  _rhizome_manifest_set_filesize(__whence, m, RHIZOME_SIZE_UNSET);
}

/* Must always set file size before setting the file hash, to avoid assertion failures.
 */
void _rhizome_manifest_set_filehash(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_filehash_t *hash)
{
  if (hash) {
    const char *v = rhizome_manifest_set(m, "filehash", alloca_tohex_rhizome_filehash_t(*hash));
    assert(v); // TODO: remove known manifest fields from vars[]
    m->filehash = *hash;
    m->has_filehash = 1;
  } else {
    rhizome_manifest_del(m, "filehash");
    m->filehash = RHIZOME_FILEHASH_NONE;
    m->has_filehash = 0;
  }
  m->finalised = 0;
}

void _rhizome_manifest_del_filehash(struct __sourceloc __whence, rhizome_manifest *m)
{
  _rhizome_manifest_set_filehash(__whence, m, NULL);
}

void _rhizome_manifest_set_tail(struct __sourceloc __whence, rhizome_manifest *m, uint64_t tail)
{
  if (tail == RHIZOME_SIZE_UNSET) {
    rhizome_manifest_del(m, "tail");
    m->is_journal = 0;
  } else {
    const char *v = rhizome_manifest_set_ui64(m, "tail", tail);
    assert(v); // TODO: remove known manifest fields from vars[]
    m->is_journal = 1;
  }
  m->tail = tail;
  m->finalised = 0;
}

void _rhizome_manifest_set_bundle_key(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_bk_t *bkp)
{
  if (bkp) {
    const char *v = rhizome_manifest_set(m, "BK", alloca_tohex_rhizome_bk_t(*bkp));
    assert(v); // TODO: remove known manifest fields from vars[]
    m->bundle_key = *bkp;
    m->has_bundle_key = 1;
    m->finalised = 0;
  } else
    _rhizome_manifest_del_bundle_key(__whence, m);
}

void _rhizome_manifest_del_bundle_key(struct __sourceloc __whence, rhizome_manifest *m)
{
  if (m->has_bundle_key) {
    rhizome_manifest_del(m, "BK");
    m->has_bundle_key = 0;
    m->bundle_key = RHIZOME_BK_NONE; // not strictly necessary, but aids debugging
    m->finalised = 0;
  } else
    assert(rhizome_manifest_get(m, "BK") == NULL);
  // Once there is no BK field, any authenticated authorship is no longer.
  if (m->authorship == AUTHOR_AUTHENTIC)
    m->authorship = AUTHOR_LOCAL;
}

void _rhizome_manifest_set_service(struct __sourceloc __whence, rhizome_manifest *m, const char *service)
{
  if (service) {
    assert(rhizome_str_is_manifest_service(service));
    const char *v = rhizome_manifest_set(m, "service", service);
    assert(v); // TODO: remove known manifest fields from vars[]
    m->service = v;
    m->finalised = 0;
  } else
    _rhizome_manifest_del_service(__whence, m);
}

void _rhizome_manifest_del_service(struct __sourceloc __whence, rhizome_manifest *m)
{
  if (m->service) {
    m->service = NULL;
    m->finalised = 0;
    rhizome_manifest_del(m, "service");
  } else
    assert(rhizome_manifest_get(m, "service") == NULL);
}

void _rhizome_manifest_set_name(struct __sourceloc __whence, rhizome_manifest *m, const char *name)
{
  m->finalised = 0;
  if (name) {
    assert(rhizome_str_is_manifest_name(name));
    const char *v = rhizome_manifest_set(m, "name", name);
    assert(v); // TODO: remove known manifest fields from vars[]
    m->name = v;
  } else {
    rhizome_manifest_del(m, "name");
    m->name = NULL;
  }
}

void _rhizome_manifest_del_name(struct __sourceloc __whence, rhizome_manifest *m)
{
  if (m->name) {
    m->name = NULL;
    m->finalised = 0;
    rhizome_manifest_del(m, "name");
  } else
    assert(rhizome_manifest_get(m, "name") == NULL);
}

void _rhizome_manifest_set_date(struct __sourceloc __whence, rhizome_manifest *m, time_ms_t date)
{
  const char *v = rhizome_manifest_set_ui64(m, "date", (uint64_t)date);
  assert(v); // TODO: remove known manifest fields from vars[]
  m->date = date;
  m->has_date = 1;
  m->finalised = 0;
}

void _rhizome_manifest_del_date(struct __sourceloc __whence, rhizome_manifest *m)
{
  if (m->has_date) {
    m->has_date = 0;
    m->finalised = 0;
    rhizome_manifest_del(m, "date");
  } else
    assert(rhizome_manifest_get(m, "date") == NULL);
}

void _rhizome_manifest_set_sender(struct __sourceloc __whence, rhizome_manifest *m, const sid_t *sidp)
{
  if (sidp) {
    const char *v = rhizome_manifest_set(m, "sender", alloca_tohex_sid_t(*sidp));
    assert(v); // TODO: remove known manifest fields from vars[]
    m->sender = *sidp;
    m->has_sender = 1;
    m->finalised = 0;
  } else
    _rhizome_manifest_del_sender(__whence, m);
}

void _rhizome_manifest_del_sender(struct __sourceloc __whence, rhizome_manifest *m)
{
  if (m->has_sender) {
    rhizome_manifest_del(m, "sender");
    m->sender = SID_ANY;
    m->has_sender = 0;
    m->finalised = 0;
  } else
    assert(rhizome_manifest_get(m, "sender") == NULL);
}

void _rhizome_manifest_set_recipient(struct __sourceloc __whence, rhizome_manifest *m, const sid_t *sidp)
{
  if (sidp) {
    const char *v = rhizome_manifest_set(m, "recipient", alloca_tohex_sid_t(*sidp));
    assert(v); // TODO: remove known manifest fields from vars[]
    m->recipient = *sidp;
    m->has_recipient = 1;
    m->finalised = 0;
  } else
    _rhizome_manifest_del_recipient(__whence, m);
}

void _rhizome_manifest_del_recipient(struct __sourceloc __whence, rhizome_manifest *m)
{
  if (m->has_recipient) {
    rhizome_manifest_del(m, "recipient");
    m->recipient = SID_ANY;
    m->has_recipient = 0;
    m->finalised = 0;
  } else
    assert(rhizome_manifest_get(m, "recipient") == NULL);
}

void _rhizome_manifest_set_crypt(struct __sourceloc __whence, rhizome_manifest *m, enum rhizome_manifest_crypt flag)
{
  switch (flag) {
    case PAYLOAD_CRYPT_UNKNOWN:
      rhizome_manifest_del(m, "crypt");
      break;
    case PAYLOAD_CLEAR: {
      const char *v = rhizome_manifest_set(m, "crypt", "0");
      assert(v); // TODO: remove known manifest fields from vars[]
      break;
    }
    case PAYLOAD_ENCRYPTED: {
      const char *v = rhizome_manifest_set(m, "crypt", "1");
      assert(v); // TODO: remove known manifest fields from vars[]
      break;
    }
    default: abort();
  }
  m->payloadEncryption = flag;
  m->finalised = 0;
}

void _rhizome_manifest_set_rowid(struct __sourceloc __whence, rhizome_manifest *m, uint64_t rowid)
{
  DEBUGF(rhizome_manifest, "SET manifest %p rowid = %"PRIu64, m, rowid);
  m->rowid = rowid;
}

void _rhizome_manifest_set_inserttime(struct __sourceloc __whence, rhizome_manifest *m, time_ms_t time)
{
  DEBUGF(rhizome_manifest, "SET manifest %p inserttime = %"PRItime_ms_t, m, time);
  m->inserttime = time;
}

void _rhizome_manifest_set_author(struct __sourceloc __whence, rhizome_manifest *m, const keyring_identity *id, const sid_t *sidp)
{
  if (id) {
    if (m->author_identity == id)
      return;
    sidp = id->box_pk;
  } else if (sidp) {
    if (m->authorship != ANONYMOUS && cmp_sid_t(&m->author, sidp) == 0)
      return;
  } else {
    _rhizome_manifest_del_author(__whence, m);
    return;
  }

  DEBUGF(rhizome_manifest, "SET manifest %p author = %s", m, alloca_tohex_sid_t(*sidp));
  m->author = *sidp;
  m->author_identity = id;
  m->authorship = AUTHOR_NOT_CHECKED;
}

void _rhizome_manifest_del_author(struct __sourceloc __whence, rhizome_manifest *m)
{
  if (m->authorship != ANONYMOUS) {
    DEBUGF(rhizome_manifest, "DEL manifest %p author", m);
    m->author = SID_ANY;
    m->author_identity = NULL;
    m->authorship = ANONYMOUS;
  }
}

/* Compute the hash of the manifest's body, including the NUL byte that separates the body from
 * the signature block, and verify that a signature is present and is correct.
 *
 * If the manifest signature is valid, ie, the signature is a self-signature using the
 * manifest's own private key, then sets the m->selfSigned flag and returns 1.
 *
 * If there are no signatures or if the signature block does not verify, then clears the
 * m->selfSigned flag and returns 0.
 *
 * Only call this function on manifests for which rhizome_manifest_validate(m) has returned true
 * (ie, m->finalised is set).
 */
int rhizome_manifest_verify(rhizome_manifest *m)
{
  assert(m->finalised);
  assert(m->manifest_body_bytes > 0);
  assert(m->manifest_all_bytes > 0);
  assert(m->manifest_body_bytes <= m->manifest_all_bytes);
  assert(m->sig_count == 0);
  if (m->manifest_body_bytes == m->manifest_all_bytes)
    assert(m->manifestdata[m->manifest_body_bytes - 1] == '\0');
  // Hash the body
  crypto_hash_sha512(m->manifesthash.binary, m->manifestdata, m->manifest_body_bytes);
  // Read signature blocks
  unsigned ofs = m->manifest_body_bytes;
  while (ofs < m->manifest_all_bytes) {
    if (rhizome_manifest_extract_signature(m, &ofs) == -1)
      break;
  }
  assert(ofs <= m->manifest_all_bytes);
  // Make sure the first signatory's public key is the bundle ID
  assert(m->has_id);
  if (m->sig_count == 0) {
    DEBUG(rhizome_manifest, "Manifest has no signature blocks, but should have self-signature block");
    m->selfSigned = 0;
    return 0;
  }
  if (memcmp(m->signatories[0], m->keypair.public_key.binary, sizeof m->keypair.public_key.binary) != 0) {
    DEBUGF(rhizome_manifest, "Manifest id does not match first signature block (signature key is %s)",
	   alloca_tohex(m->signatories[0], crypto_sign_PUBLICKEYBYTES)
	  );
    m->selfSigned = 0;
    return 0;
  }
  m->selfSigned = 1;
  return 1;
}

static void rhizome_manifest_clear(rhizome_manifest *m)
{
  while (m->var_count) {
    --m->var_count;
    free((char *) m->vars[m->var_count]);
    free((char *) m->values[m->var_count]);
    m->vars[m->var_count] = m->values[m->var_count] = NULL;
  }
  while (m->sig_count) {
    --m->sig_count;
    free(m->signatories[m->sig_count]);
    m->signatories[m->sig_count] = NULL;
  }
  m->malformed = NULL;
  m->has_id = 0;
  m->has_filehash = 0;
  m->is_journal = 0;
  m->filesize = RHIZOME_SIZE_UNSET;
  m->tail = RHIZOME_SIZE_UNSET;
  m->version = 0;
  // TODO initialise more fields
}

int rhizome_manifest_inspect(const char *buf, size_t len, struct rhizome_manifest_summary *summ)
{
  const char *const end = buf + len;
  int has_bid = 0;
  int has_version = 0;
  const char *begin = buf;
  const char *eol = NULL;
  enum { Label, Value, Error } state = Label;
  const char *p;
  for (p = buf; state != Error && p < end && *p; ++p)
    switch (state) {
      case Label:
	if (*p == '=') {
	  if (!rhizome_manifest_field_label_is_valid(begin, p - begin))
	    state = Error; // bad field name
	  else {
	    int *has = NULL;
	    if (p == begin + 2 && strncmp(begin, "id", 2) == 0)
	      has = &has_bid;
	    else if (p == begin + 7 && strncmp(begin, "version", 7) == 0)
	      has = &has_version;
	    state = Value;
	    if (has) {
	      if (*has)
		state = Error; // duplicate
	      else {
		*has = 1;
		begin = p + 1;
	      }
	    }
	  }
	}
	break;
      case Value:
	if (*p == '\r' && !eol)
	  eol = p;
	else if (*p == '\n') {
	  if (!eol)
	    eol = p;
	  if (has_bid == 1) {
	    const char *e;
	    if (parse_rhizome_bid_t(&summ->bid, begin, eol - begin, &e) == 0 && e == eol)
	      has_bid = 2;
	    else
	      state = Error; // invalid "id" field
	  } else if (has_version == 1) {
	    const char *e;
	    if (str_to_uint64(begin, 10, &summ->version, &e) && e == eol)
	      has_version = 2;
	    else
	      state = Error; // invalid "version" field
	  }
	  if (state == Value) {
	    state = Label;
	    begin = p + 1;
	    eol = NULL;
	  }
	} else if (eol)
	  state = Error; // CR not followed by LF
	break;
      default:
	abort();
    }
  if (p < end && *p == '\0')
    ++p;
  summ->body_len = p - buf;
  return state == Label && has_bid == 2 && has_version == 2;
}

/* Parse a Rhizome text manifest from its internal buffer up to and including the terminating NUL
 * character which marks the start of the signature block.
 *
 * Prior to calling, the caller must set up m->manifest_all_bytes to the length of the manifest
 * text, including the signature block, and set m->manifestdata[0..m->manifest_all_bytes-1] to
 * contain the manifest text and signature block to be parsed.
 *
 * A "well formed" manifest consists of a series of zero or more lines with the form:
 *
 *	LABEL "=" VALUE [ CR ] LF
 *
 * where LABEL matches the regular expression [A-Za-z][A-Za-z0-9]* (identifier without underscore)
 *       VALUE is any value that does not contain NUL, CR or LF (leading and trailing spaces are
 *	       not stripped from VALUE)
 *       NUL is ASCII 0
 *       CR is ASCII 13
 *       LF is ASCII 10
 *
 * Unpacks all parsed field labels and string values into the m->vars[] and m->values[] arrays, as
 * pointers to malloc(3)ed NUL terminated strings, in the order they appear, and sets m->var_count
 * to the number of fields unpacked.  Sets m->manifest_body_bytes to the number of bytes in the text
 * portion up to and including the optional NUL that starts the signature block (if present).
 *
 * Returns 1 if the manifest is not well formed (syntax violation), any essential field is
 * malformed, or if there are any duplicate fields.  In this case the m->vars[] and m->values[]
 * arrays are not set and the manifest is returned to the state it was in prior to calling.
 *
 * Returns 0 if the manifest is well formed, if there are no duplicate fields, and if all essential
 * fields are valid.  Counts invalid non-essential fields and unrecognised fields in m->malformed.
 *
 * Returns -1 if there is an unrecoverable error (eg, malloc(3) returns NULL, out of memory).
 *
 * @author Andrew Bettison <andrew@servalproject.com>
 */
int rhizome_manifest_parse(rhizome_manifest *m)
{
  IN();
  assert(m->manifest_all_bytes <= sizeof m->manifestdata);
  assert(m->manifest_body_bytes == 0);
  assert(m->var_count == 0);
  assert(!m->finalised);
  assert(m->malformed == NULL);
  assert(!m->has_id);
  assert(!m->has_filehash);
  assert(!m->is_journal);
  assert(m->filesize == RHIZOME_SIZE_UNSET);
  assert(m->tail == RHIZOME_SIZE_UNSET);
  assert(m->version == 0);
  assert(!m->has_date);
  assert(!m->has_sender);
  assert(!m->has_recipient);
  assert(m->payloadEncryption == PAYLOAD_CRYPT_UNKNOWN);
  unsigned invalid = 0;
  unsigned has_invalid_core = 0;
  unsigned has_duplicate = 0;
  const char *const end = (const char *)m->manifestdata + m->manifest_all_bytes;
  const char *p;
  unsigned line_number = 0;
  for (p = (const char *)m->manifestdata; !invalid && p < end && *p; ++p) {
    ++line_number;
    const char *const plabel = p++;
    while (p < end && *p && *p != '=' && *p != '\n')
      ++p;
    if (p == end || *p != '=') {
      DEBUGF(rhizome_manifest, "Invalid manifest line %u: %s", line_number, alloca_toprint(-1, plabel, p - plabel + 1));
      ++invalid;
      break;
    }
    assert(p < end);
    assert(*p == '=');
    const char *const pvalue = ++p;
    while (p < end && *p && *p != '\n')
      ++p;
    if (p >= end || *p != '\n') {
      DEBUGF(rhizome_manifest, "Missing manifest newline at line %u: %s", line_number, alloca_toprint(-1, plabel, p - plabel));
      ++invalid;
      break;
    }
    const char *const eol = (p > pvalue && p[-1] == '\r') ? p - 1 : p;
    enum rhizome_manifest_parse_status status = rhizome_manifest_parse_field(m, plabel, pvalue - plabel - 1, pvalue, eol - pvalue);
    int status_ok = 0;
    switch (status) {
      case RHIZOME_MANIFEST_ERROR:
	RETURN(-1);
      case RHIZOME_MANIFEST_OK:
	status_ok = 1;
	break;
      case RHIZOME_MANIFEST_SYNTAX_ERROR:
	status_ok = 1;
	++invalid;
	break;
      case RHIZOME_MANIFEST_DUPLICATE_FIELD:
	status_ok = 1;
	++has_duplicate;
	break;
      case RHIZOME_MANIFEST_INVALID:
	status_ok = 1;
	++has_invalid_core;
	break;
      case RHIZOME_MANIFEST_MALFORMED:
	status_ok = 1;
	m->malformed = "Invalid field";
	break;
      case RHIZOME_MANIFEST_OVERFLOW:
	status_ok = 1;
	++invalid;
	break;
    }
    if (!status_ok)
      FATALF("status = %d", status);
    assert(p < end);
    assert(*p == '\n');
  }
  if ((p < end && *p) || invalid || has_invalid_core || has_duplicate) {
    rhizome_manifest_clear(m);
    RETURN(1);
  }
  // The null byte is included in the body (and checksum), not the signature block
  if (p < end) {
    assert(*p == '\0');
    ++p;
  }
  m->manifest_body_bytes = p - (const char *)m->manifestdata;
  RETURN(0);
  OUT();
}

typedef int MANIFEST_FIELD_TESTER(const rhizome_manifest *);
typedef void MANIFEST_FIELD_UNSETTER(struct __sourceloc, rhizome_manifest *);
typedef void MANIFEST_FIELD_COPIER(struct __sourceloc, rhizome_manifest *, const rhizome_manifest *);
typedef int MANIFEST_FIELD_PARSER(rhizome_manifest *, const char *);

static int _rhizome_manifest_test_id(const rhizome_manifest *m)
{
  return m->has_id;
}
static void _rhizome_manifest_unset_id(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_set_id(m, NULL);
}
static void _rhizome_manifest_copy_id(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_id(m, srcm->has_id ? &srcm->keypair.public_key : NULL);
}
static int _rhizome_manifest_parse_id(rhizome_manifest *m, const char *text)
{
  rhizome_bid_t bid;
  if (str_to_rhizome_bid_t(&bid, text) == -1)
    return 0;
  rhizome_manifest_set_id(m, &bid);
  return 1;
}

static int _rhizome_manifest_test_version(const rhizome_manifest *m)
{
  return m->version != 0;
}
static void _rhizome_manifest_unset_version(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_del_version(m);
}
static void _rhizome_manifest_copy_version(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_version(m, srcm->version);
}
static int _rhizome_manifest_parse_version(rhizome_manifest *m, const char *text)
{
  uint64_t version;
  if (!str_to_uint64(text, 10, &version, NULL) || version == 0)
    return 0;
  rhizome_manifest_set_version(m, version);
  return 1;
}

static int _rhizome_manifest_test_filehash(const rhizome_manifest *m)
{
  return m->has_filehash;
}
static void _rhizome_manifest_unset_filehash(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_set_filehash(m, NULL);
}
static void _rhizome_manifest_copy_filehash(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_filehash(m, srcm->has_filehash ? &srcm->filehash : NULL);
}
static int _rhizome_manifest_parse_filehash(rhizome_manifest *m, const char *text)
{
  rhizome_filehash_t hash;
  if (str_to_rhizome_filehash_t(&hash, text) == -1)
    return 0;
  rhizome_manifest_set_filehash(m, &hash);
  return 1;
}

static int _rhizome_manifest_test_filesize(const rhizome_manifest *m)
{
  return m->filesize != RHIZOME_SIZE_UNSET;
}
static void _rhizome_manifest_unset_filesize(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_set_filesize(m, RHIZOME_SIZE_UNSET);
}
static void _rhizome_manifest_copy_filesize(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_filesize(m, srcm->filesize);
}
static int _rhizome_manifest_parse_filesize(rhizome_manifest *m, const char *text)
{
  uint64_t size;
  if (!str_to_uint64(text, 10, &size, NULL) || size == RHIZOME_SIZE_UNSET)
    return 0;
  rhizome_manifest_set_filesize(m, size);
  return 1;
}

static int _rhizome_manifest_test_tail(const rhizome_manifest *m)
{
  return m->is_journal;
}
static void _rhizome_manifest_unset_tail(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_set_tail(m, RHIZOME_SIZE_UNSET);
}
static void _rhizome_manifest_copy_tail(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_tail(m, srcm->tail);
}
static int _rhizome_manifest_parse_tail(rhizome_manifest *m, const char *text)
{
  uint64_t tail;
  if (!str_to_uint64(text, 10, &tail, NULL) || tail == RHIZOME_SIZE_UNSET)
    return 0;
  rhizome_manifest_set_tail(m, tail);
  return 1;
}

static int _rhizome_manifest_test_BK(const rhizome_manifest *m)
{
  return m->has_bundle_key;
}
static void _rhizome_manifest_unset_BK(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_del_bundle_key(m);
}
static void _rhizome_manifest_copy_BK(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_bundle_key(m, srcm->has_bundle_key ? &srcm->bundle_key : NULL);
}
static int _rhizome_manifest_parse_BK(rhizome_manifest *m, const char *text)
{
  rhizome_bk_t bk;
  if (str_to_rhizome_bk_t(&bk, text) == -1)
    return 0;
  rhizome_manifest_set_bundle_key(m, &bk);
  return 1;
}

static int _rhizome_manifest_test_service(const rhizome_manifest *m)
{
  return m->service != NULL;
}
static void _rhizome_manifest_unset_service(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_del_service(m);
}
static void _rhizome_manifest_copy_service(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_service(m, srcm->service);
}
static int _rhizome_manifest_parse_service(rhizome_manifest *m, const char *text)
{
  if (!rhizome_str_is_manifest_service(text))
    return 0;
  rhizome_manifest_set_service(m, text);
  return 1;
}

static int _rhizome_manifest_test_date(const rhizome_manifest *m)
{
  return m->has_date;
}
static void _rhizome_manifest_unset_date(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_del_date(m);
}
static void _rhizome_manifest_copy_date(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  if (srcm->has_date)
    rhizome_manifest_set_date(m, srcm->date);
  else
    rhizome_manifest_del_date(m);
}
static int _rhizome_manifest_parse_date(rhizome_manifest *m, const char *text)
{
  int64_t date;
  if (!str_to_int64(text, 10, &date, NULL))
    return 0;
  rhizome_manifest_set_date(m, date);
  return 1;
}

static int _rhizome_manifest_test_sender(const rhizome_manifest *m)
{
  return m->has_sender;
}
static void _rhizome_manifest_unset_sender(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_set_sender(m, NULL);
}
static void _rhizome_manifest_copy_sender(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_sender(m, srcm->has_sender ? &srcm->sender : NULL);
}
static int _rhizome_manifest_parse_sender(rhizome_manifest *m, const char *text)
{
  sid_t sid;
  if (str_to_sid_t(&sid, text) == -1)
    return 0;
  rhizome_manifest_set_sender(m, &sid);
  return 1;
}

static int _rhizome_manifest_test_recipient(const rhizome_manifest *m)
{
  return m->has_recipient;
}
static void _rhizome_manifest_unset_recipient(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_set_recipient(m, NULL);
}
static void _rhizome_manifest_copy_recipient(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_recipient(m, srcm->has_recipient ? &srcm->recipient : NULL);
}
static int _rhizome_manifest_parse_recipient(rhizome_manifest *m, const char *text)
{
  sid_t sid;
  if (str_to_sid_t(&sid, text) == -1)
    return 0;
  rhizome_manifest_set_recipient(m, &sid);
  return 1;
}

static int _rhizome_manifest_test_name(const rhizome_manifest *m)
{
  return m->name != NULL;
}
static void _rhizome_manifest_unset_name(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_del_name(m);
}
static void _rhizome_manifest_copy_name(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_name(m, srcm->name);
}
static int _rhizome_manifest_parse_name(rhizome_manifest *m, const char *text)
{
  rhizome_manifest_set_name(m, text);
  return 1;
}

static int _rhizome_manifest_test_crypt(const rhizome_manifest *m)
{
  return m->payloadEncryption != PAYLOAD_CRYPT_UNKNOWN;
}
static void _rhizome_manifest_unset_crypt(struct __sourceloc __whence, rhizome_manifest *m)
{
  rhizome_manifest_set_crypt(m, PAYLOAD_CRYPT_UNKNOWN);
}
static void _rhizome_manifest_copy_crypt(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  rhizome_manifest_set_crypt(m, srcm->payloadEncryption);
}
static int _rhizome_manifest_parse_crypt(rhizome_manifest *m, const char *text)
{
  if (!(strcmp(text, "0") == 0 || strcmp(text, "1") == 0))
    return 0;
  rhizome_manifest_set_crypt(m, (text[0] == '1') ? PAYLOAD_ENCRYPTED : PAYLOAD_CLEAR);
  return 1;
}

static struct rhizome_manifest_field_descriptor {
    const char *label;
    int core;
    MANIFEST_FIELD_TESTER *test;
    MANIFEST_FIELD_UNSETTER *unset;
    MANIFEST_FIELD_COPIER *copy;
    MANIFEST_FIELD_PARSER *parse;
}
    rhizome_manifest_fields[] = {
#define FIELD(CORE, NAME) \
        { #NAME, CORE, _rhizome_manifest_test_ ## NAME, _rhizome_manifest_unset_ ## NAME, _rhizome_manifest_copy_ ## NAME, _rhizome_manifest_parse_ ## NAME }
	FIELD(1, id),
	FIELD(1, version),
	FIELD(1, filehash),
	FIELD(1, filesize),
	FIELD(1, tail),
	FIELD(0, BK),
	FIELD(0, service),
	FIELD(0, date),
	FIELD(0, sender),
	FIELD(0, recipient),
	FIELD(0, name),
	FIELD(0, crypt),
#undef FIELD
    };

static struct rhizome_manifest_field_descriptor *get_rhizome_manifest_field_descriptor(const char *label)
{
  unsigned i;
  for (i = 0; i < NELS(rhizome_manifest_fields); ++i)
    if (strcasecmp(label, rhizome_manifest_fields[i].label) == 0)
      return &rhizome_manifest_fields[i];
  return NULL;
}

/* Overwrite a Rhizome manifest with fields from another.  Used in the "add bundle" application API
 * when the application supplies a partial manifest to override or add to existing manifest fields.
 *
 * Returns -1 if a field in the destination manifest cannot be overwritten for an unrecoverable
 * reason, eg, out of memory or too many variables, leaving the destination manifest in an undefined
 * state.
 *
 * @author Andrew Bettison <andrew@servalproject.com>
 */
int _rhizome_manifest_overwrite(struct __sourceloc __whence, rhizome_manifest *m, const rhizome_manifest *srcm)
{
  unsigned i;
  for (i = 0; i < NELS(rhizome_manifest_fields); ++i) {
      struct rhizome_manifest_field_descriptor *desc = &rhizome_manifest_fields[i];
      if (desc->test(srcm)) {
	DEBUGF(rhizome_manifest, "COPY manifest %p %s to:", srcm, desc->label);
	desc->copy(__whence, m, srcm);
      }
  }
  for (i = 0; i < srcm->var_count; ++i) {
    struct rhizome_manifest_field_descriptor *desc = get_rhizome_manifest_field_descriptor(srcm->vars[i]);
    if (!desc)
      if (_rhizome_manifest_set(__whence, m, srcm->vars[i], srcm->values[i]) == NULL)
	return -1;
  }
  return 0;
}

int rhizome_manifest_field_label_is_valid(const char *field_label, size_t field_label_len)
{
  if (field_label_len == 0 || field_label_len > MAX_MANIFEST_FIELD_LABEL_LEN)
    return 0;
  if (!isalpha(field_label[0]))
    return 0;
  unsigned i;
  for (i = 1; i != field_label_len; ++i)
    if (!isalnum(field_label[i]))
      return 0;
  return 1;
}

int rhizome_manifest_field_value_is_valid(const char *field_value, size_t field_value_len)
{
  if (field_value_len >= MAX_MANIFEST_BYTES)
    return 0;
  unsigned i;
  for (i = 0; i < field_value_len; ++i)
    if (field_value[i] == '\0' || field_value[i] == '\r' || field_value[i] == '\n')
      return 0;
  return 1;
}

/* Parse a single Rhizome manifest field.  Used for incremental construction or modification of
 * manifests.
 *
 * If the supplied field_label is invalid (does not conform to the syntax for field names) or the
 * field_value string is too long or contains a NUL (ASCII 0), CR (ASCII 13) or LF (ASCII 10), then
 * returns RHIZOME_MANIFEST_SYNTAX_ERROR and leaves the manifest unchanged.
 *
 * If a field with the given label already exists in the manifest, then returns
 * RHIZOME_MANIFEST_DUPLICATE_FIELD without modifying the manifest.  (To overwrite an existing
 * field, first remove it by calling rhizome_manifest_remove_field() then call
 * rhizome_manifest_parse_field().)
 *
 * If the maximum number of fields are already occupied in the manifest, then returns
 * RHIZOME_MANIFEST_OVERFLOW and leaves the manifest unchanged.
 *
 * If the supplied field_value is invalid (does not parse according to the field's syntax, eg,
 * unsigned integer) then returns RHIZOME_MANIFEST_INVALID if it is a core field, otherwise returns
 * RHIZOME_MANIFEST_MALFORMED and leaves the manifest unchanged.  Unsupported fields are not parsed;
 * their value string is simply stored, so they cannot evoke a MALFORMED result.
 *
 * Otherwise, sets the relevant element(s) of the manifest structure and appends the field_label and
 * field_value strings into the m->vars[] and m->values[] arrays, as pointers to malloc(3)ed NUL
 * terminated strings, and increments m->var_count.  Returns RHIZOME_MANIFEST_OK.
 *
 * Returns -1 (RHIZOME_MANIFEST_ERROR) if there is an unrecoverable error (eg, malloc(3) returns
 * NULL, out of memory).
 *
 * @author Andrew Bettison <andrew@servalproject.com>
 */
enum rhizome_manifest_parse_status
rhizome_manifest_parse_field(rhizome_manifest *m, const char *field_label, size_t field_label_len, const char *field_value, size_t field_value_len)
{
  // Syntax check on field label.
  if (!rhizome_manifest_field_label_is_valid(field_label, field_label_len)) {
    DEBUGF(rhizome_manifest, "Invalid manifest field name: %s", alloca_toprint(100, field_label, field_label_len));
    return RHIZOME_MANIFEST_SYNTAX_ERROR;
  }
  const char *label = alloca_strndup(field_label, field_label_len);
  // Sanity and syntax check on field value.
  if (!rhizome_manifest_field_value_is_valid(field_value, field_value_len)) {
    DEBUGF(rhizome_manifest, "Invalid manifest field value: %s=%s", label, alloca_toprint(100, field_value, field_value_len));
    return RHIZOME_MANIFEST_SYNTAX_ERROR;
  }
  const char *value = alloca_strndup(field_value, field_value_len);
  struct rhizome_manifest_field_descriptor *desc = get_rhizome_manifest_field_descriptor(label);
  enum rhizome_manifest_parse_status status = RHIZOME_MANIFEST_OK;
  assert(m->var_count <= NELS(m->vars));
  if (desc ? desc->test(m) : rhizome_manifest_get(m, label) != NULL) {
    DEBUGF(rhizome_manifest, "Duplicate field at %s=%s", label, alloca_toprint(100, field_value, field_value_len));
    status = RHIZOME_MANIFEST_DUPLICATE_FIELD;
  } else if (m->var_count == NELS(m->vars)) {
    DEBUGF(rhizome_manifest, "Manifest field limit reached at %s=%s", label, alloca_toprint(100, field_value, field_value_len));
    status = RHIZOME_MANIFEST_OVERFLOW;
  } else if (desc) {
    if (!desc->parse(m, value)) {
      DEBUGF(rhizome_manifest, "Manifest field parse failed at %s=%s", label, alloca_toprint(100, field_value, field_value_len));
      status = desc->core ? RHIZOME_MANIFEST_INVALID : RHIZOME_MANIFEST_MALFORMED;
    }
  } else if (rhizome_manifest_set(m, label, value) == NULL)
    status = RHIZOME_MANIFEST_ERROR;
  if (status != RHIZOME_MANIFEST_OK) {
    DEBUGF(rhizome_manifest, "SKIP manifest %p %s = %s (status=%d)", m, label, alloca_str_toprint(value), status);
  }
  return status;
}

/* Remove the field with the given label from the manifest.
 *
 * @author Andrew Bettison <andrew@servalproject.com>
 */
int rhizome_manifest_remove_field(rhizome_manifest *m, const char *field_label, size_t field_label_len)
{
  if (!rhizome_manifest_field_label_is_valid(field_label, field_label_len)) {
    DEBUGF(rhizome_manifest, "Invalid manifest field name: %s", alloca_toprint(100, field_label, field_label_len));
    return 0;
  }
  const char *label = alloca_strndup(field_label, field_label_len);
  struct rhizome_manifest_field_descriptor *desc = NULL;
  unsigned i;
  for (i = 0; desc == NULL && i < NELS(rhizome_manifest_fields); ++i)
    if (strcasecmp(label, rhizome_manifest_fields[i].label) == 0)
      desc = &rhizome_manifest_fields[i];
  if (!desc)
    return rhizome_manifest_del(m, label);
  if (!desc->test(m))
    return 0;
  desc->unset(__WHENCE__, m);
  return 1;
}

/* If all essential (transport) fields are present and well formed then sets the m->finalised field
 * and returns 1, otherwise returns 0.
 *
 * Sets m->malformed if any non-essential fields are missing or invalid.  It is up to the caller to
 * check m->malformed and decide whether or not to process a malformed manifest.
 *
 * @author Andrew Bettison <andrew@servalproject.com>
 */
int rhizome_manifest_validate(rhizome_manifest *m)
{
  return (m->finalised || rhizome_manifest_validate_reason(m) == NULL) ? 1 : 0;
}

/* If all essential (transport) fields are present and well formed then sets the m->finalised field
 * and returns NULL, otherwise returns a pointer to a static string (not malloc(3)ed) describing the
 * problem.
 *
 * If any non-essential fields are missing or invalid, then sets m->malformed to point to a static
 * string describing the problem.  It is up to the caller to check m->malformed and decide whether
 * or not to process a malformed manifest.
 *
 * @author Andrew Bettison <andrew@servalproject.com>
 */
const char *rhizome_manifest_validate_reason(rhizome_manifest *m)
{
  const char *reason = NULL;
  if (!m->has_id)
    reason = "Missing 'id' field";
  else if (m->version == 0)
    reason = "Missing 'version' field";
  else if (m->filesize == RHIZOME_SIZE_UNSET)
    reason = "Missing 'filesize' field";
  else if (m->filesize == 0 && m->has_filehash)
    reason = "Spurious 'filehash' field";
  else if (m->filesize != 0 && !m->has_filehash)
    reason = "Missing 'filehash' field";
  if (reason)
    DEBUG(rhizome_manifest, reason);
  if (m->service == NULL)
    m->malformed = "Missing 'service' field";
  else if (strcmp(m->service, RHIZOME_SERVICE_FILE) == 0) {
    if (m->name == NULL)
      m->malformed = "Manifest with service='" RHIZOME_SERVICE_FILE "' missing 'name' field";
  } else if (strcmp(m->service, RHIZOME_SERVICE_MESHMS) == 0
          || strcmp(m->service, RHIZOME_SERVICE_MESHMS2) == 0
  ) {
    if (!m->has_recipient)
      m->malformed = "Manifest missing 'recipient' field";
    else if (!m->has_sender)
      m->malformed = "Manifest missing 'sender' field";
  }
  else if (!rhizome_str_is_manifest_service(m->service))
    m->malformed = "Manifest invalid 'service' field";
  else if (!m->has_date)
    m->malformed = "Missing 'date' field";
  if (m->malformed)
    DEBUG(rhizome_manifest, m->malformed);
  m->finalised = (reason == NULL);
  return reason;
}

int rhizome_read_manifest_from_file(rhizome_manifest *m, const char *filename)
{
  ssize_t bytes = read_whole_file(filename, m->manifestdata, sizeof m->manifestdata);
  if (bytes == -1)
    return -1;
  m->manifest_all_bytes = (size_t) bytes;
  return rhizome_manifest_parse(m);
}

rhizome_manifest *_rhizome_new_manifest(struct __sourceloc __whence)
{
  rhizome_manifest *m=emalloc_zero(sizeof(rhizome_manifest));
  if (m){
    DEBUGF(rhizome_manifest, "NEW manifest %p", m);

    // Set global defaults for a manifest (which are not zero)
    rhizome_manifest_clear(m);
  }
  return m;
}

void _rhizome_manifest_free(struct __sourceloc __whence, rhizome_manifest *m)
{
  if (!m) return;
  DEBUGF(rhizome_manifest, "FREE manifest %p", m);
  
  /* Free variable and signature blocks. */
  rhizome_manifest_clear(m);
  free(m);
  return;
}

/* Converts the variable list into manifest text body and computes the hash.  Does not sign.
 * Returns 0 if successful, -1 if the result exceeds the manifest size limit.
 */
static struct rhizome_bundle_result rhizome_manifest_pack_variables(rhizome_manifest *m)
{
  assert(m->var_count <= NELS(m->vars));
  strbuf sb = strbuf_local_buf(m->manifestdata);
  unsigned i;
  for (i = 0; i < m->var_count; ++i) {
    strbuf_puts(sb, m->vars[i]);
    strbuf_putc(sb, '=');
    strbuf_puts(sb, m->values[i]);
    strbuf_putc(sb, '\n');
  }
  if (strbuf_overrun(sb)) {
    return rhizome_bundle_result_sprintf(
	RHIZOME_BUNDLE_STATUS_MANIFEST_TOO_BIG,
	"Manifest too big: body of %zu bytes exceeds limit of %zu",
	strbuf_count(sb) + 1, sizeof m->manifestdata);
  }
  m->manifest_body_bytes = strbuf_len(sb) + 1;
  DEBUGF(rhizome, "Repacked variables into manifest: %zu bytes", m->manifest_body_bytes);
  m->manifest_all_bytes = m->manifest_body_bytes;
  m->selfSigned = 0;
  return rhizome_bundle_result(RHIZOME_BUNDLE_STATUS_NEW);
}

/* Sign this manifest using it's own BID secret key.  Manifest must not already be signed.
 * Manifest body hash must already be computed.
 */
static struct rhizome_bundle_result rhizome_manifest_selfsign(rhizome_manifest *m)
{
  assert(m->manifest_body_bytes > 0);
  assert(m->manifest_body_bytes <= sizeof m->manifestdata);
  assert(m->manifestdata[m->manifest_body_bytes - 1] == '\0');
  assert(m->manifest_body_bytes == m->manifest_all_bytes); // no signature yet
  if (!m->haveSecret)
    return rhizome_bundle_result_static(RHIZOME_BUNDLE_STATUS_READONLY, "Missing bundle secret");

  size_t sigLen = 1 + crypto_sign_BYTES + crypto_sign_PUBLICKEYBYTES;
  if (sizeof m->manifestdata - m->manifest_body_bytes < sigLen)
    return rhizome_bundle_result_sprintf(RHIZOME_BUNDLE_STATUS_MANIFEST_TOO_BIG,
	    "Manifest too big: body of %zu + signature of %zu bytes exceeds limit of %zu",
	    m->manifest_body_bytes,
	    sigLen,
	    sizeof m->manifestdata);

  crypto_hash_sha512(m->manifesthash.binary, m->manifestdata, m->manifest_body_bytes);
  uint8_t *p = &m->manifestdata[m->manifest_body_bytes];
  *p++ = 0x17; // CryptoSign
  if (crypto_sign_detached(p, NULL, m->manifesthash.binary, sizeof m->manifesthash.binary, m->keypair.binary))
    return rhizome_bundle_result_static(RHIZOME_BUNDLE_STATUS_ERROR, "crypto_sign_detached() failed");
  p+=crypto_sign_BYTES;
  bcopy(m->keypair.public_key.binary, p, crypto_sign_BYTES);
  m->manifest_all_bytes = m->manifest_body_bytes + sigLen;
  m->selfSigned = 1;
  return rhizome_bundle_result(RHIZOME_BUNDLE_STATUS_NEW);
}

int rhizome_write_manifest_file(rhizome_manifest *m, const char *path, char append)
{
  DEBUGF(rhizome, "write manifest (%zd bytes) to %s", m->manifest_all_bytes, path);
  assert(m->finalised);
  int fd = open(path, O_WRONLY | O_CREAT | (append ? O_APPEND : 0), 0666);
  if (fd == -1)
    return WHYF_perror("open(%s,O_WRONLY|O_CREAT%s,0666)", alloca_str_toprint(path), append ? "|O_APPEND" : "");
  int ret = 0;
  unsigned char marker[4];
  struct iovec iov[2];
  int iovcnt = 1;
  iov[0].iov_base = m->manifestdata;
  iov[0].iov_len = m->manifest_all_bytes;
  if (append) {
    write_uint16(marker, m->manifest_all_bytes);
    marker[2] = 0x41;
    marker[3] = 0x10;
    iov[1].iov_base = marker;
    iov[1].iov_len = sizeof marker;
    iovcnt = 2;
  }
  if (writev_all(fd, iov, iovcnt) == -1)
    ret = -1;
  if (close(fd) == -1)
    ret = WHY_perror("close");
  return ret;
}

int rhizome_manifest_dump(rhizome_manifest *m, const char *msg)
{
  unsigned i;
  WHYF("Dumping manifest %s:", msg);
  for(i=0;i<m->var_count;i++)
    WHYF("[%s]=[%s]\n", m->vars[i], m->values[i]);
  return 0;
}

struct rhizome_bundle_result rhizome_manifest_finalise(rhizome_manifest *m, rhizome_manifest **mout, int deduplicate)
{
  IN();
  assert(*mout == NULL);
  if (!m->finalised) {
    const char *reason = rhizome_manifest_validate_reason(m);
    if (reason)
      RETURN(rhizome_bundle_result_static(RHIZOME_BUNDLE_STATUS_INVALID, reason));
  }
  // The duplicate detection logic exists to filter out files repeatedly added with no existing
  // manifest (ie, "de-bounce" for the "Add File" user interface action).
  // 1. If a manifest was supplied with a bundle ID, don't check for a duplicate.
  // 2. Never perform duplicate detection on journals (the first append does not supply a bundle ID,
  //    but all subsequent appends supply a bundle ID, so are caught by case (1)).
  if (deduplicate && m->haveSecret != EXISTING_BUNDLE_ID && !m->is_journal) {
    enum rhizome_bundle_status status = rhizome_find_duplicate(m, mout);
    switch (status) {
      case RHIZOME_BUNDLE_STATUS_DUPLICATE:
	assert(*mout != NULL);
	assert(*mout != m);
	RETURN(rhizome_bundle_result(status));
      case RHIZOME_BUNDLE_STATUS_ERROR:
	if (*mout != NULL && *mout != m) {
	  rhizome_manifest_free(*mout);
	  *mout = NULL;
	}
	RETURN(rhizome_bundle_result(status));
      case RHIZOME_BUNDLE_STATUS_NEW:
	break;
      default:
	FATALF("rhizome_find_duplicate() returned %d", status);
    }
  }
  assert(*mout == NULL);
  *mout = m;

  /* Convert to final form for signing and writing to disk */
  struct rhizome_bundle_result result = rhizome_manifest_pack_variables(m);
  if (result.status != RHIZOME_BUNDLE_STATUS_NEW)
    RETURN(result);
  rhizome_bundle_result_free(&result);

  /* Sign it */
  assert(!m->selfSigned);
  result = rhizome_manifest_selfsign(m);
  if (result.status == RHIZOME_BUNDLE_STATUS_NEW) {
    assert(m->selfSigned);
    rhizome_bundle_result_free(&result);
    /* mark manifest as finalised */
    result.status = rhizome_add_manifest_to_store(m, mout);
  }

  RETURN(result);
  OUT();
}

/* Returns 1 if the name was successfully set, 0 if not.
 */
int rhizome_manifest_set_name_from_path(rhizome_manifest *m, const char *filepath)
{
  const char *name = strrchr(filepath, '/');
  if (name)
    ++name; // skip '/'
  else
    name = filepath;
  if (!rhizome_str_is_manifest_name(name)) {
    WARNF("invalid rhizome name %s -- not used", alloca_str_toprint(name));
    return 0;
  }
  rhizome_manifest_set_name(m, name);
  return 1;
}

/* Fill in a few missing manifest fields, to make it easier to use when adding new files:
 *  - use the current time for "date" and "version"
 *  - use the given author SID, or the 'sender' if present, as the author
 *  - create an ID if there is none, otherwise authenticate the existing one
 *  - if service is file, then use the payload file's basename for "name"
 *
 * Return a rhizome_bundle_status code together with a pointer to a text string describing the
 * reason for the failure (always an internal/unrecoverable error).  The string is accompanied by a
 * pointer to a "free" method (eg, free(3)) that must be called to release the string before the
 * pointer is discarded.
 */
struct rhizome_bundle_result rhizome_fill_manifest(rhizome_manifest *m, const char *filepath)
{
  /* Set version of manifest from current time if not already set. */
  if (m->version == 0)
    rhizome_manifest_set_version(m, gettime_ms());

  /* Fill in the bundle secret and bundle ID.
   */
  switch (m->haveSecret) {
  case SECRET_UNKNOWN:
    // If the Bundle Id is already known, then derive the bundle secret from BK if known.
    if (m->has_id) {
      DEBUGF(rhizome, "discover secret for bundle bid=%s", alloca_tohex_rhizome_bid_t(m->keypair.public_key));
      rhizome_authenticate_author(m);
      break;
    }
    // If there is no Bundle Id, then create a new bundle Id and secret from scratch.
    DEBUG(rhizome, "creating new bundle");
    if (rhizome_manifest_createid(m) == -1) {
      return rhizome_bundle_result_static(RHIZOME_BUNDLE_STATUS_ERROR, "Could not bind manifest to an ID");
    }
    // to set the BK field...    
    FALLTHROUGH; // fall through
  case NEW_BUNDLE_ID:
    assert(m->has_id);
    // If the manifest has no author but does have a 'sender' field, then use the
    // sender as the author.
    if (m->authorship == ANONYMOUS && m->has_sender)
      rhizome_manifest_set_author(m, &m->sender);
    // If we know the author then set the BK field.
    if (m->authorship != ANONYMOUS) {
      DEBUGF(rhizome, "set BK field for bid=%s", alloca_tohex_rhizome_bid_t(m->keypair.public_key));
      rhizome_manifest_add_bundle_key(m);
    }
    break;
  case EXISTING_BUNDLE_ID:
    // If modifying an existing bundle, try to discover the bundle secret key and the author.
    assert(m->has_id);
    DEBUGF(rhizome, "modifying existing bundle bid=%s", alloca_tohex_rhizome_bid_t(m->keypair.public_key));
    rhizome_authenticate_author(m);
    // TODO assert that new version > old version?
    break;
  default:
    FATALF("haveSecret = %d", m->haveSecret);
  }

  switch (m->authorship) {
  case ANONYMOUS:
  case AUTHOR_AUTHENTIC:
    break; // all good
  case AUTHOR_UNKNOWN:
    return rhizome_bundle_result_static(RHIZOME_BUNDLE_STATUS_READONLY, "Author is not in keyring");
  case AUTHOR_IMPOSTOR:
    return rhizome_bundle_result_static(RHIZOME_BUNDLE_STATUS_READONLY, "Incorrect author");
  case AUTHENTICATION_ERROR:
    return rhizome_bundle_result_static(RHIZOME_BUNDLE_STATUS_ERROR, "Error authenticating author");
  default:
    FATALF("m->authorship = %d", (int)m->authorship);
  }

  /* Service field must already be set.
   */
  if (m->service == NULL)
    return rhizome_bundle_result_static(RHIZOME_BUNDLE_STATUS_INVALID, "Missing 'service' field");

  DEBUGF(rhizome, "manifest contains service=%s", m->service);

  /* Fill in 'date' field to current time unless already set.
   */
  if (!m->has_date) {
    rhizome_manifest_set_date(m, (int64_t) gettime_ms());
    DEBUGF(rhizome, "missing 'date', set default date=%"PRItime_ms_t, m->date);
  }

  /* Fill in 'name' field if service=file.
   */
  if (strcasecmp(RHIZOME_SERVICE_FILE, m->service) == 0) {
    if (m->name) {
      DEBUGF(rhizome, "manifest already contains name=%s", alloca_str_toprint(m->name));
    } else if (filepath)
      rhizome_manifest_set_name_from_path(m, filepath);
    else
      DEBUGF(rhizome, "manifest missing 'name'");
  }

  /* Fill in 'crypt' field.  Anything sent from one person to another should be considered private
   * and encrypted by default.
   */
  if (   m->payloadEncryption == PAYLOAD_CRYPT_UNKNOWN
      && m->has_recipient
      && !is_sid_t_broadcast(m->recipient)
  ) {
    DEBUGF(rhizome, "Implicitly adding payload encryption due to presense of recipient field");
    rhizome_manifest_set_crypt(m, PAYLOAD_ENCRYPTED);
  }

  return rhizome_bundle_result(RHIZOME_BUNDLE_STATUS_NEW);
}

/* Work out the authorship status of the bundle without performing expensive cryptographic checks.
 * Sets the 'authorship' element and returns 1 if an author was found, 0 if not.
 *
 * @author Andrew Bettison <andrew@servalproject.com>
 */
int rhizome_lookup_author(rhizome_manifest *m)
{
  IN();
  switch (m->authorship) {
    case AUTHOR_LOCAL:
    case AUTHOR_AUTHENTIC:
    case AUTHOR_REMOTE:
      RETURN(1);
    case AUTHOR_NOT_CHECKED:
      DEBUGF(rhizome, "manifest %p lookup author=%s", m, alloca_tohex_sid_t(m->author));
      if (keyring && keyring_find_identity_sid(keyring, &m->author)) {
	DEBUGF(rhizome, "found author");
	m->authorship = AUTHOR_LOCAL;
	RETURN(1);
      }
      // fall through
    case ANONYMOUS:
      if (m->has_sender) {
	DEBUGF(rhizome, "manifest %p lookup sender=%s", m, alloca_tohex_sid_t(m->sender));
	if (keyring && keyring_find_identity_sid(keyring, &m->sender)) {
	  DEBUGF(rhizome, "found sender");
	  rhizome_manifest_set_author(m, &m->sender);
	  m->authorship = AUTHOR_LOCAL;
	  RETURN(1);
	} else if(crypto_ismatching_sign_sid(&m->keypair.public_key, &m->sender)) {
	  // if the author matches the bundle id...
	  DEBUGF(rhizome, "sender matches manifest signature");
	  m->author = m->sender;
	  m->authorship = AUTHOR_REMOTE;
	  RETURN(1);
	}
      }
      // fall through
    case AUTHENTICATION_ERROR:
    case AUTHOR_UNKNOWN:
    case AUTHOR_IMPOSTOR:
      RETURN(0);
  }
  FATALF("m->authorship = %d", m->authorship);
  RETURN(0);
  OUT();
}